JP6493229B2 - Head mounted display - Google Patents

Description

  The present invention relates to a head mounted display.

  A head-mounted display (hereinafter referred to as “HMD”) that projects an image on a part of a user's field of view is known. In this type of HMD, it is often possible for the user to freely adjust to which position in the field of view the image is projected by making the display unit movable. For example, Patent Document 1 discloses an HMD having a band, an image output unit support arm, and an image output unit. The band is fixed to the user's head. The image output unit support arm is movably supported by the band. An image output unit is provided at one end of the image output unit support arm. The image output unit outputs image light. The image output unit moves in response to the image output unit support arm projecting and retracting from the opening of the image output unit support arm housing unit provided in the band. The image output unit is provided with a diopter adjustment knob for diopter adjustment.

JP 2004-286833 A

  In the above-described HMD, the rotational radius direction of the diopter adjustment knob and the protruding direction of the image output unit support arm are orthogonal to each other. For this reason, there is a problem that the position of the image output unit can be adjusted only in a limited direction. However, if the image output unit support arm can move the image output unit in other directions or the image output unit can be rotated in the same direction as the diopter adjustment knob, When the diopter adjustment knob is operated after the position of the image output unit is adjusted, a force may be applied to the image output unit in accordance with the operation, and the position of the image output unit may be shifted. In this case, there is a problem that the user needs to adjust the position of the image output unit again.

  The objective of this invention is providing the head mounted display which can suppress the shift | offset | difference of a display part, when an operation part is operated.

  The head mounted display according to the first aspect of the present invention includes a holding unit having a display unit for displaying an image, an operation unit provided on a surface of the holding unit, a first support unit for supporting the holding unit, A first adjustment unit that is connected between the first support unit and the holding unit and that can be held by moving a position of the holding unit with respect to the first support unit; and when the operation unit is operated The direction of the force acting on the holding portion and the direction in which the holding portion can be moved by the first adjusting portion have mutually parallel components, and the first adjustment is performed when the operating portion is operated. The magnitude of the second moment required for moving the position of the holding portion relative to the first support portion by the first adjustment portion is larger than the magnitude of the first moment acting on the portion. All the holding part can be moved by the part It is larger for direction.

  The head mounted display which concerns on a 1st aspect enables the position adjustment of the holding | maintenance part by a user by making the position of the holding | maintenance part with respect to a 1st support part movable by the 1st adjustment part. Further, in the head mounted display, it is necessary to move the holding unit by the first adjusting unit rather than the magnitude of the first moment acting on the first adjusting unit when the operation unit provided on the holding unit is operated. The magnitude of the second moment is set so as to increase in all directions in which the holding section can be moved by the first adjustment section. In this case, even if the force according to operation with respect to the operation part acts on the holding part, the movement of the holding part relative to the first support part is suppressed by the first adjusting part. The position of the holding portion with respect to the first support portion is difficult to shift before and after the operation on the operation portion. Therefore, the user does not need to readjust the position of the holding unit after operating the operation unit, and can continue to use the head mounted display.

  In the first aspect, the first adjustment unit may be capable of moving the position of the holding unit with three or more degrees of freedom with respect to the first support unit. In this case, the head mounted display can suppress the movement of the holding part relative to the first support part while allowing the user to finely adjust the position of the holding part.

  In the first aspect, the first adjustment unit includes a spherical body part and a receiving part that slide relative to each other in accordance with a movement of the position of the holding part with respect to the first support part. An annular member that is rotatably provided around a predetermined rotation axis with respect to the holding portion, and is interposed between the surface of the holding portion and the operation portion, and the rotation shaft passes through the inside of the ring. An elastic member may be further provided, and a second contact area between the spherical body portion and the receiving portion of the first adjustment portion may be larger than a first contact area between the operation portion and the elastic member. In this case, the head-mounted display can suppress water droplets, dust, and the like from entering the holding portion through the gap between the surface of the holding portion and the operation portion by the elastic member. Moreover, the head mounted display can make it difficult to shift the position of the holding part with respect to the first support part before and after the operation with respect to the operation part by making the second contact area larger than the first contact area.

  1st aspect WHEREIN: The said 1st support part supports the said holding | maintenance part by one end side, The 2nd support part connected with the other end side of the said 1st support part, The said 1st support part, and the said 2nd A second adjustment unit connected between the support unit and capable of holding the first support unit by moving the position of the first support unit relative to the second support unit, and the holding unit when the operation unit is operated The direction of the force acting on the first adjusting unit and the direction in which the first supporting unit can be moved by the second adjusting unit have components parallel to each other, and when the operating unit is operated, the second adjusting unit The magnitude of the fourth moment required for moving the position of the first support part relative to the second support part by the second adjustment part is larger than the magnitude of the third moment acting. The first support part may be large in all directions in which the first support part can move.The head mounted display has a second adjustment unit that can be held by moving the position of the first support unit relative to the second support unit. In this case, since the degree of freedom of movement of the holding unit is increased, the user can finely adjust the position of the holding unit. Further, the fourth adjustment necessary for moving the position of the first support portion relative to the second support portion by the second adjustment portion, rather than the magnitude of the third moment acting on the second adjustment portion when the operation portion is operated. The magnitude of the moment is set so as to increase in all directions in which the first support portion can move by the second adjustment portion. In this case, even if the force according to operation with respect to the operation part acts on the holding part, the movement of the holding part with respect to the second support part is suppressed by the second adjusting part. The position of the holding portion with respect to the second support portion is difficult to shift before and after the operation on the operation portion. Therefore, the user does not need to readjust the position of the holding unit after operating the operation unit, and can continue to use the head mounted display.

  A head-mounted display according to a second aspect of the present invention includes a holding unit that displays an image, an operation unit provided on a surface of the holding unit, a first support unit that supports the holding unit, and the first support. And a first adjusting unit that is connected between the first support unit and can be held by moving the position of the holding unit relative to the first support unit, and the holding unit is operated when the operation unit is operated The direction of the force acting on the first adjusting unit and the direction in which the holding unit can be moved by the first adjusting unit have components parallel to each other, and act on the first adjusting unit when the operating unit is operated. The magnitude of the second force necessary for moving the position of the holding portion relative to the first support portion by the first adjustment portion is greater than the magnitude of the first force by the first adjustment portion. The part is large in all possible directions of movement To.

  The head mounted display which concerns on a 2nd aspect enables the position adjustment of the holding | maintenance part by a user by making the position of the holding | maintenance part with respect to a 1st support part movable by the 1st adjustment part. Further, in the head mounted display, it is necessary to move the holding unit by the first adjusting unit rather than the magnitude of the first force acting on the first adjusting unit when the operation unit provided on the holding unit is operated. The magnitude of the second force is set so as to increase in all directions in which the holding unit can be moved by the first adjusting unit. In this case, even if the force according to operation with respect to the operation part acts on the holding part, the movement of the holding part relative to the first support part is suppressed by the first adjusting part. The position of the holding portion with respect to the first support portion is difficult to shift before and after the operation on the operation portion. Therefore, the user does not need to readjust the position of the holding unit after operating the operation unit, and can continue to use the head mounted display.

  In the first aspect or the second aspect, the first adjustment unit causes the first adjustment unit to have a first frictional force that is a static frictional force between a plurality of first surfaces that slide relative to each other in response to the operation unit being operated. The second frictional force, which is a static frictional force between a plurality of second surfaces that slide relative to each other as the position of the holding portion relative to the first support portion is moved, may be greater. In this case, even when a force is applied according to an operation on the operation unit, the position of the holding unit with respect to the first support unit is difficult to move. For this reason, the head mounted display can maintain the position of the holding part with respect to the first support part more stably before and after the operation on the operation part.

  In the first aspect and the second aspect, the second static friction coefficients of the plurality of second surfaces may be larger than the first static friction coefficients of the plurality of first surfaces. In this case, even when a force is applied according to an operation on the operation unit, the position of the holding unit with respect to the first support unit is difficult to move. For this reason, the head mounted display can maintain the position of the holding part with respect to the first support part more stably before and after the operation on the operation part.

  In the first aspect or the second aspect, the material of at least one of the plurality of first surfaces may be a fluororesin. Fluororesin is known as an elastic member having a particularly small coefficient of friction. In this case, the head mounted display can easily increase the second frictional force more than the first frictional force, and can easily increase the second frictional coefficient more than the first frictional coefficient. Even when force is applied, the position of the holding portion relative to the first support portion is difficult to move. For this reason, the head mounted display can maintain the position of the holding part with respect to the first support part more stably before and after the operation on the operation part.

  2nd aspect WHEREIN: The said 1st support part supports the said holding | maintenance part by one end side, The 2nd support part connected with the other end side of the said 1st support part, The said 1st support part, and the said 2nd A second adjustment unit connected between the support unit and capable of holding the first support unit by moving the position of the first support unit relative to the second support unit, and the holding unit when the operation unit is operated The direction of the force acting on the first adjusting unit and the direction in which the first supporting unit can be moved by the second adjusting unit have components parallel to each other, and when the operating unit is operated, the second adjusting unit The magnitude of the fourth force required to move the position of the first support part relative to the second support part by the second adjustment part may be larger than the magnitude of the third force acting. The head mounted display has a second adjustment unit that can be held by moving the position of the first support unit relative to the second support unit. In this case, since the degree of freedom of movement of the holding unit is increased, the user can finely adjust the position of the holding unit. Further, the fourth adjustment necessary for moving the position of the first support portion relative to the second support portion by the second adjustment portion is larger than the magnitude of the third force acting on the second adjustment portion when the operation portion is operated. The magnitude of the force is set so as to increase in all directions in which the first support portion is movable by the second adjustment portion. In this case, even if the force according to operation with respect to the operation part acts on the holding part, the movement of the holding part with respect to the second support part is suppressed by the second adjusting part. The position of the holding portion with respect to the second support portion is difficult to shift before and after the operation on the operation portion. Therefore, the user does not need to readjust the position of the holding unit after operating the operation unit, and can continue to use the head mounted display.

  In the first aspect or the second aspect, the operation portion is provided to be rotatable about a predetermined rotation axis with respect to the holding portion, and is an annular shape interposed between the surface of the holding portion and the operation portion. An elastic member may be further provided, and the rotating shaft may pass through an opening of the elastic member. In this case, the head-mounted display can suppress the water droplets, dust, and the like from entering the holding portion through the gap between the surface of the holding portion and the operation member by the elastic member. Although an annular elastic member is interposed between the surface of the holding portion and the operation portion, there is a concern that the force acting according to the operation of the operation portion becomes larger than when no elastic member is interposed. Even in such a case, the first support can be provided even when a force is applied in response to an operation on the operation unit if the design is made with attention to materials and configurations in a range that satisfies the relationship of the present invention. The position of the holding part with respect to the part becomes difficult to move. For this reason, the head mounted display can maintain the position of the holding part with respect to the first support part more stably before and after the operation on the operation part.

  In the second aspect, the first adjustment unit and the second adjustment unit may move the position of the holding unit with respect to the second support unit with six degrees of freedom. In this case, the head mounted display can suppress the movement of the holding unit relative to the first support unit while allowing the user to finely adjust the position of the holding unit.

It is a front view of HMD1. It is a right view of HMD1. It is a front view of the connection tool. FIG. 4 is an exploded perspective view of the connection tool 9, the first ball joint 2, and the connection member 7. 3 is an exploded perspective view of the image display device 11. FIG. 3 is a cross-sectional view of an operation member 15 and an adjustment mechanism 19. FIG. It is a perspective view of the 1st ball joint 2 (state with socket 22). 3 is a cross-sectional view of the first ball joint 2. FIG. It is a perspective view of the 2nd ball joint 3 (state with socket 22). 3 is a cross-sectional view of a second ball joint 3. FIG. 3 is a schematic diagram of an image display device 11 and a second ball joint 3. FIG. 2 is a schematic diagram of an image display device 11, a first ball joint 2, and a second ball joint 3. FIG. It is a perspective view of HMD1 in a modification. It is a schematic diagram of the image display apparatus 11 and the 2nd translation mechanism 5 in a modification. It is a schematic diagram of the image display apparatus 11, the 1st translation mechanism 4, and the 2nd translation mechanism 5 in a modification.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, a head mounted display (hereinafter referred to as “HMD”) 1 is an optically transmissive see-through HMD. The HMD 1 includes a mounting tool 8, a connection tool 9, and an image display device 11. The scenery light in front of the user's eyes is directly guided to the user's eyes by passing through the half mirror 14 of the image display device 11. The projection format of HMD1 is a virtual image projection type. The half mirror 14 reflects the light of the image displayed on the liquid crystal panel accommodated in the image display device 11 toward one eye of the user. The HMD 1 can make the user recognize the image superimposed on the scene in front of him.

  Hereinafter, in order to help understand the description of the figure, the upper side, lower side, left side, right side, front side, and rear side of the HMD 1 are defined. The front side, the rear side, the upper side, and the lower side of the HMD 1 correspond to, for example, the left side, the right side, the upper side, and the lower side in FIG. The left side and the right side of the HMD 1 correspond to, for example, the left side and the right side of FIG. The upper side, the lower side, the left side, the right side, the front side, and the rear side of the HMD 1 correspond to the upper side, the lower side, the right side, the left side, the front side, and the rear side, respectively, for the user wearing the wearing tool 8.

<Mounting tool 8>
As shown in FIGS. 1 and 2, the mounting tool 8 is made of a flexible material such as resin or metal (for example, stainless steel). The mounting tool 8 includes a first portion 81 and second portions 82 and 83. In the following, for ease of understanding, the mounting tool 8 will be described as being divided into a first part 81 and second parts 82 and 83. However, the mounting tool 8 includes the first part 81 and the second part 82. , 83 are not divided into individual members, but are integral members as a whole.

  The first portion 81 and the second portions 82 and 83 are each curved and elongated plate-like members. The first portion 81 is a portion of the wearing tool 8 that extends in the left-right direction between the position 8A and the position 8B. The first portion 81 is curved in a convex shape on the front side. The position 8 </ b> A is located on the left side of the center 84 in the left-right direction of the wearing tool 8. The position 8B is located on the right side of the center 84 in the left-right direction of the wearing tool 8. The second portion 82 is a portion of the wearing tool 8 that extends rearward from the position 8A. The second portion 83 is a portion of the wearing tool 8 that extends rearward from the position 8B. The second portions 82 and 83 each extend in a direction in which the rear ends approach each other. The wearing tool 8 is fixed to the user's head in a state in which the first portion 81 and the second portions 82 and 83 are in contact with the frontal, right and left heads of the user, respectively. . In this state, the first portion 81 extends in the left-right direction along the user's forehead. Hereinafter, the side surrounded by the first portion 81 and the second portions 82 and 83 of the mounting tool 8 is referred to as “the inner side of the mounting tool 8”, and the side opposite to the inner side of the mounting tool 8 is referred to as “the mounting tool 8. It is called “outside”.

<Connector 9>
As shown in FIG. 3, the connection tool 9 is substantially rod-shaped. The connection tool 9 is made of resin or metal. The connection tool 9 extends in the vertical direction as viewed from the front. More specifically, as shown in FIG. 2, the connector 9 extends in a direction in which the lower end portion is inclined forward with respect to the vertical direction. The connection tool 9 has a space inside. As shown in FIG. 3, the connection tool 9 includes a first member 9A and a second member 9B. The space inside the connection tool 9 is formed by the second member 9B covering the opening on the right side of the first member 9A. The first member 9A has two circular holes 90A penetrating in the left-right direction. As shown in FIG. 4, the second member 9 </ b> B has two cylindrical protrusions 90 </ b> B that protrude toward the left side. The second member 9B is fixed to the first member 9A by fitting the protrusions 90B into the holes 90A.

  As shown in FIG. 1, the upper end portion of the connection tool 9 is connected to the mounting tool 8 via a first ball joint 2 and a connection member 7 described later. As shown in FIG. 2, the lower end portion of the connection tool 9 is connected to the image display device 11 via a second ball joint 3 and a connection member 6 described later. The image display device 11 is attached to the mounting tool 8 by the connecting tool 9. The connection tool 9 holds the image display device 11 at a position separated from the mounting tool 8. The connection tool 9 can place the half mirror 14 of the image display device 11 in front of the user's left eye in a state where the mounting tool 8 is fixed to the user's head.

<Image display device 11>
As shown in FIGS. 1 and 2, the image display device 11 includes a housing 12. The housing 12 has a substantially rectangular parallelepiped shape with curved corners. The housing 12 has a hollow box shape. As shown in FIG. 1, the left side of the housing 12 is opened. As shown in FIG. 5, the housing 12 is formed by combining a first housing 13 and a second housing 16. The first housing 13 includes a front wall portion 13A, an upper wall portion 13B, and a lower wall portion 13C. The front wall portion 13A is curved forward. The left end of the front wall portion 13A is recessed from the both ends in the up-down direction toward the center in the up-down direction on the right side to form a substantially arc. A half mirror 14 (see FIG. 1) is provided on the rear side of the portion surrounded by the arc at the left end of the front wall portion 13A and in the portion sandwiched between the upper wall portion 13B and the lower wall portion 13C in the vertical direction. Be placed. A hole 131 that penetrates in the front-rear direction is formed in the front wall portion 13A, and a groove 132 is formed around the hole 131. An operation member 15 described later fits into the groove 132 from the front side. The adjusting mechanism 19 described later enters the hole 131 from the rear side and connects to the rear surface of the operation member 15. The front wall portion 13A supports the operation member 15 in a rotatable manner.

  The image unit 18 includes a first holding member 181, a liquid crystal display device 182, and a second holding member 183. The first holding member 181 holds a liquid crystal display device 182 described later at the right end. The first holding member 181 has a hollow, substantially cylindrical member that is open on the left and right sides on the left side of the portion that holds the liquid crystal display device 182. The first holding member 181 is held at a fixed position with respect to the housing 12. The liquid crystal display device 182 includes a glass substrate and a liquid crystal panel. The liquid crystal panel is a well-known rectangular liquid crystal panel. The liquid crystal panel generates image light by displaying an image on the left surface. The glass substrate is provided on the left side of the liquid crystal panel and protects the liquid crystal panel. The second holding member 183 has a control board. The control board is connected to the liquid crystal display device 182 via a flexible printed board (not shown). The control board outputs a control signal to the liquid crystal display device 182 to display an image corresponding to the image data on the liquid crystal panel.

  The optical system 17 is disposed on the left side of the image unit 18. The optical system 17 includes a deflection unit 171 and a lens unit 172. The lens unit 172 is a hollow member that is open on both the left and right sides. The lens unit 172 has a plurality of lenses (not shown) inside. The image light generated by the image unit 18 enters the inside from the right end and exits from the left end toward the left side. The plurality of lenses collects image light incident from the right side and emits it to the left side. The lens unit 172 has a convex portion 172A that protrudes forward on the front surface. The convex portion 172A fits into a cam groove formed on the rear surface of the adjusting mechanism 19 described later. The lens unit 172 can move in the left-right direction.

  The deflection unit 171 is disposed on the left side of the lens unit 172. The deflection unit 171 includes a half mirror 14 (see FIG. 1) and a holder 171A. The half mirror 14 is configured, for example, by depositing a metal such as aluminum or silver on a transparent resin or glass substrate so as to have a predetermined reflectance (for example, 50%). The half mirror 14 can deflect the image light that passes through the lens unit 172 and enters from the right side to the rear side. When image light enters the user's eyes, the user can visually recognize a virtual image based on the image light. Moreover, the half mirror 14 can also transmit the external light incident from the front side to the rear side. The holder 171 </ b> A holds the half mirror 14. The holder 171A is sandwiched from above and below by the upper wall portion 13B and the lower wall portion 13C of the first housing 13.

  The operation member 15 has a circular plate shape. One surface of the operation member 15 faces the front direction, and the other surface faces the rear direction. The operation member 15 is rotatable about a rotation shaft 15A that is a virtual straight line extending in the front-rear direction. An O-ring 133 is interposed between the groove 132 provided on the front wall portion 13 </ b> A of the first housing 13 and the operation member 15. The O-ring 133 is an annular elastic member and has an opening 133A at the center. The rotating shaft 15A passes through the inside of the opening 133A of the O-ring 133. As illustrated in FIG. 6, the operation member 15 includes a protruding portion 151 that protrudes toward the rear side. The protruding portion 151 is held on the surface of the front wall portion 13 </ b> A of the first housing 13 with the O-ring 133 interposed between the protruding portion 151 and the groove 132. The material of the O-ring 133 is fluororubber. When the operation member 15 rotates about the rotation shaft 15A, the peripheral surface 151A of the protrusion 151 of the operation member 15 and the inner surface of the O-ring 133 slide with each other.

  Hereinafter, the total area of the surfaces of the operation member 15 that slide during operation is referred to as “first contact area” and is expressed as “S1”. The average static friction coefficient on the sliding surface is referred to as “first friction coefficient” and is expressed as “k1”. The average static frictional force on the sliding surface is referred to as “first frictional force”, and the magnitude of the first frictional force is expressed as “F1”. A value obtained by averaging the distances of the sliding surface from the rotation shaft 15A is referred to as a “first average radius” and is expressed as “r1”.

  As shown in FIG. 5, the adjusting mechanism 19 has a circular plate shape. The adjusting mechanism 19 has a protruding portion 19A that protrudes forward from the vicinity of the center of the circle. The protruding portion 19A enters the hole 131 of the front wall portion 13A of the first housing 13 from the rear side. As shown in FIG. 6, the front end portion of the protruding portion 19 </ b> A is fitted to the protruding portion 151 of the operation member 15. Accordingly, the operation member 15 and the adjustment mechanism 19 sandwich the front wall portion 13A from both the front and rear sides. In this state, the O-ring 133 is sandwiched between the protruding portion 151 of the operation member 15 and the groove 132 of the front wall portion 13A. The adjusting mechanism 19 can rotate integrally with the operation member 15. The operation member 15 and the adjustment mechanism 19 may be integrally formed. A cam groove (not shown) is provided on the rear surface of the adjusting mechanism 19. The cam groove is formed when a part of the rear surface of the adjustment mechanism 19 is recessed forward. The cam groove extends in a spiral shape around the circular center of the adjustment mechanism 19. The convex portion 172A of the lens unit 172 is fitted into the cam groove from the rear.

  When the adjustment mechanism 19 rotates according to the rotation of the operation member 15, the cam groove applies a force to the convex portion 172 </ b> A of the lens unit 172. When the operation member 15 rotates clockwise as viewed from the front side, the lens unit 172 moves to the right side. When the operation member 15 rotates counterclockwise when viewed from the front side, the lens unit 172 moves to the left side. The distance between the plurality of lenses held by the lens unit 172 and the image unit 18 changes according to the rotation of the operation member 15. When the distance between the plurality of lenses and the image unit 18 changes, the spread angle of the image light that becomes a virtual image visually recognized by the user also changes. Therefore, the user can adjust the focus by rotating the operation member 15.

<Connection member 7>
As shown in FIGS. 3 and 4, the connecting member 7 includes a connecting portion 71 and a cylindrical portion 72. The connection part 71 connects the connection member 7 with respect to the mounting tool 8 (refer FIG. 1, FIG. 2) so that attachment or detachment is possible. The connecting portion 71 has an outer portion 71A and an inner portion 71B. The outer portion 71A contacts the upper side, the lower side, and the outer side of the wearing tool 8. The inner part 71 </ b> B contacts the inner side of the wearing tool 8. The inner portion 71B has a cylindrical protruding portion 711 protruding toward the right side. The outer portion 71 </ b> A has a hole (not shown) penetrating in the left-right direction at a portion that contacts the outside of the wearing tool 8. As shown in FIG. 4, a screw 712 is inserted into a hole (not shown) of the outer portion 71A from the right side to the left side. The screw 712 is screwed into the protruding portion 711 of the inner portion 71B. The outer portion 71 </ b> A and the inner portion 71 </ b> B are fixed by screws 712 with the wearing tool 8 being sandwiched therebetween.

  The cylindrical portion 72 is a cylindrical member. The cylindrical portion 72 protrudes to the right from the outer portion 71A of the connecting portion 71. The cylindrical portion 72 includes a first cylindrical portion 72A and a second cylindrical portion 72B that have different outer surface diameters. The second cylindrical portion 72B is disposed on the right side of the first cylindrical portion 72A. The diameter of the outer surface of the second cylindrical portion 72B is smaller than the diameter of the outer surface of the first cylindrical portion 72A. A space is formed inside the second cylindrical portion 72B. The left end of the second cylindrical portion 72B is closed by the bottom portion 721 (see FIG. 8). A thread is formed on the outer surface of the second cylindrical portion 72B. The socket 22 of the first ball joint 2 described later is connected to the second cylindrical portion 72B.

<First ball joint 2>
As shown in FIGS. 4, 7, and 8, the first ball joint 2 includes a ball stud 21, a socket 22, a receiving portion 23, and a pressing portion 24. The ball stud 21 includes a sphere portion 21A, a rod portion 21B, and a base portion 21C. The spherical portion 21A is a spherical portion. The rod portion 21B is a cylindrical portion extending from the spherical portion 21A toward the right side. The diameter of the cross section of the rod portion 21B is smaller than the diameter of the spherical portion 21A. As shown in FIG. 8, the bar portion 21 </ b> B extends along an imaginary line 212 that extends radially from the center 211 of the spherical body portion 21 </ b> A, bends diagonally rightward, and further extends along the imaginary line 213. The base portion 21C is connected to the opposite side of the spherical portion 21A side of the rod portion 21B. As shown in FIG. 4, a recess 911 is provided at the upper end of the first member 9 </ b> A of the connector 9. As shown in FIG. 8, the base 21C of the ball stud 21 fits into the recess 911 from the left side. A hole (not shown) penetrating in the left-right direction is formed at the bottom of the recess 911. A screw 912 is inserted into the hole from the right side to the left side. The screw 912 is screwed into a screw hole provided in the base portion 21 </ b> C of the ball stud 21. Thereby, the ball stud 21 is fixed to the connector 9 by the screw 912.

  The receiving part 23 is accommodated inside the second cylindrical part 72 </ b> B of the connecting member 7. The receiving portion 23 is an elastically deformable rubber that functions as a cushioning material. The left side surface of the receiving portion 23 contacts the bottom portion 721 of the second cylindrical portion 72B. A concave portion 23 </ b> B that is recessed in a circular shape is provided on the right side surface of the receiving portion 23. The concave portion 23B comes into contact with the left half of the spherical portion 21A of the ball stud 21 from the left side. The presser portion 24 has a hemispherical shape. The opening of the presser portion 24 faces the left side. The presser portion 24 has a circular hole 24A penetrating in the left-right direction. The rod portion 21B of the ball stud 21 is inserted into the hole 24A. The diameter of the hole 24A is substantially the same as the diameter of the cross section of the rod portion 21B of the ball stud 21. The wall 24 </ b> B corresponding to the inner surface of the presser 24 contacts the right half of the spherical body 21 </ b> A of the ball stud 21 from the right side. The spherical portion 21A is sandwiched from both the left and right sides by the concave portion 23B of the receiving portion 23 and the wall portion 24B of the pressing portion 24.

  The socket 22 is a cylindrical member extending in the left-right direction. The inner diameter of the socket 22 is substantially the same as the outer diameter of the second cylindrical portion 72 </ b> B of the connection member 7. A screw thread is formed on the left end portion of the inner surface of the socket 22. This screw thread is screwed into a screw thread formed on the outer surface of the second cylindrical portion 72B. As a result, the socket 22 is connected to the connection member 7. The spherical body portion 21 </ b> A, the receiving portion 23, and the presser portion 24 of the ball stud 21 are accommodated in a space surrounded by the second cylindrical portion 72 </ b> B and the socket 22.

  As shown in FIG. 7, a wall 221 that extends while curving toward the center is provided at the right end of the socket 22. The wall 221 is formed with a circular hole 22A penetrating in the left-right direction. The rod portion 21B of the ball stud 21 is inserted into the hole 22A. The inner surface of the hole 22A of the wall portion 221 contacts the outer surface 24C of the pressing portion 24 from the right side. A part of the right side of the presser portion 24 protrudes from the hole 22 </ b> A to the outside of the socket 22.

  As shown in FIG. 8, in a state where the socket 22 is screwed into the second cylindrical portion 72B of the connection member 7, the wall portion 221 of the socket 22 pushes the presser portion 24 toward the left side. The spherical portion 21 </ b> A of the ball stud 21 in contact with the wall portion 24 </ b> B of the presser portion 24 is pushed by the presser portion 24 to move to the left side and is pressed against the receiving portion 23. As a result, the state in which the spherical portion 21A is sandwiched between the left and right sides by the receiving portion 23 and the pressing portion 24 is maintained.

  The distance between the bottom portion 721 of the second cylindrical portion 72B and the wall portion 221 of the socket 22 varies depending on the degree of screwing of the socket 22 to the second cylindrical portion 72B. Depending on the distance between the bottom portion 721 and the wall portion 221, the force by which the socket 22 pushes the holding portion 24 and the force by which the receiving portion 23 and the holding portion 24 sandwich the spherical portion 21A change. In the present embodiment, the HMD 1 is screwed into the second cylindrical portion 72B so that the holding portion 24 can move with respect to the socket 22 and the spherical portion 21A can move with respect to the receiving portion 23. It is assumed that the degree of combination is adjusted in advance. In this case, as shown in FIG. 7, the ball stud 21 can rotate in the direction indicated by the arrow 2 </ b> A around the virtual line 212 extending radially from the center 211 of the sphere 21 </ b> A. Further, the ball stud 21 is a range in which the rod portion 21B does not contact the hole 22A of the wall portion 221 of the socket 22, that is, a range surrounded by a virtual conical surface 214 connecting the center 211 and the inner end portion of the wall portion 221. Thus, it can move in the direction indicated by the arrow 2B. When the ball stud 21 moves in the direction indicated by the arrows 2 </ b> A and 2 </ b> B, the presser portion 24 also moves as the ball stud 21 moves. On the other hand, when the ball stud 21 moves in the direction indicated by the arrows 2A and 2B, the inner surface of the hole 22A of the wall portion 221 of the socket 22 and the outer surface 24C of the pressing portion 24 slide with each other, and the spherical portion 21A. And the recess 23B of the receiving portion 23 slide on each other.

  The above-described movement of the ball stud 31 is rotational movement about two axes (for example, a first axis extending in the front-rear direction and a second axis extending in the up-down direction) orthogonal to the virtual line 212 and orthogonal to each other. Corresponds to a part of If the left-right direction in FIG. 7 is the X-axis, the front-rear direction is the Y-axis, and the up-down direction is the Z-axis, the movement around the virtual line 212 is the rotation Xθ around the X-axis, and the movement within the conical surface 214 is around the Y-axis. This is expressed as a combination of the rotation Yθ and the rotation Zθ around the Z axis. That is, the first ball joint 2 can move the ball stud 21 with three degrees of freedom.

  Hereinafter, the total area of the surfaces that slide when the ball stud 21 of the first ball joint 2 rotates is referred to as “third contact area” and is expressed as “S3”. The average static friction coefficient on the sliding surface is referred to as “third friction coefficient” and is expressed as “k3”. The average static frictional force on the sliding surface is referred to as “third frictional force”, and the magnitude of the third frictional force is expressed as “F3”. The average radius of the sphere portion 21A of the ball stud 21 is referred to as “third average radius” and is expressed as “r3”. The rotation of the ball stud 21 of the first ball joint 2 is referred to as “the first ball joint 2 rotates”.

<Connection member 6>
As shown in FIG. 2, the connection member 6 is a substantially prismatic member extending in the front-rear direction. The front surface of the connection member 6 is connected to the rear surface of the image display device 11. The connecting member 6 has a cylindrical portion 62 (see FIG. 10) that protrudes rightward from the right side surface of the rear end. A space is formed inside the cylindrical portion 62. The left end of the cylindrical portion 62 is closed by a bottom portion 621 (see FIG. 10). A thread is formed on the outer surface of the cylindrical portion 62. A socket 32 of the second ball joint 3 described later is connected to the cylindrical portion 62.

<Second ball joint 3>
As shown in FIGS. 9 and 10, the configuration of the second ball joint 3 is substantially the same as that of the first ball joint 2 except for some configurations. Below, in order to avoid duplication with description of the 1st ball joint 2 in the above, explanation of the 2nd ball joint 3 is omitted or simplified. The second ball joint 3 includes a ball stud 31, a socket 32, a receiving part 33, and a pressing part 34. The ball stud 31, the socket 32, the receiving portion 33, and the holding portion 34 correspond to the ball stud 21, the socket 22, the receiving portion 23, and the holding portion 24 of the first ball joint 2, respectively.

  The ball stud 31 includes a sphere portion 31A, a rod portion 31B, and a base portion 31C. The shapes of the spherical portion 31A, the rod portion 31B, and the base portion 31C are the same as the shapes of the spherical portion 21A, the rod portion 21B, and the base portion 21C of the ball stud 21. The bar portion 31B extends along a virtual line 312 extending radially from the center 311 of the spherical body portion 31A, bends obliquely rightward and further extends along the virtual line 313. As shown in FIG. 4, a recess 913 is provided at the lower end of the first member 9 </ b> A of the connector 9. As shown in FIG. 10, the base 31C of the ball stud 31 fits into the recess 913 from the left side. A hole (not shown) penetrating in the left-right direction is formed at the bottom of the recess 913. A screw 914 is inserted into the hole from the right side to the left side. The screw 914 is screwed into a screw hole provided in the base portion 31 </ b> C of the ball stud 31. Thereby, the ball stud 31 is fixed to the connector 9 by the screw 914.

  The receiving portion 33 is accommodated inside the cylindrical portion 62 of the connecting member 6. The receiving portion 33 is an elastically deformable rubber that functions as a cushioning material. The left side surface of the receiving portion 33 contacts the bottom portion 621 of the cylindrical portion 62. On the right side surface of the receiving portion 33, a concave portion 33B that is recessed in a circular shape is provided. The concave portion 33B comes into contact with the left half of the spherical portion 31A of the ball stud 31 from the left side.

  The shape of the presser part 34 is different from that of the presser part 24 of the first ball joint 2. The presser portion 34 has a substantially cylindrical shape. The presser portion 34 includes a first cylindrical portion 341 and a second cylindrical portion 342 having different inner surface diameters. The second cylindrical portion 342 is disposed on the right side of the first cylindrical portion 341. The diameter of the inner surface of the second cylindrical portion 342 is smaller than the diameter of the inner surface of the first cylindrical portion 341. The left end portion of the first cylindrical portion 341 and the right end portion of the second cylindrical portion 342 are opened. Of the inner surface of the presser portion 34, the stepped portion 34B of the connecting portion between the first cylindrical portion 341 and the second cylindrical portion 342 is slightly on the right side of the center in the left-right direction of the spherical portion 31A of the ball stud 31. Contact. The rod portion 31 </ b> B of the ball stud 31 is inserted into the opening 34 </ b> A at the right end portion of the presser portion 34. The diameter of the opening 34A is larger than the diameter of the cross section of the rod portion 31B of the ball stud 31, and is substantially the same as the diameter of a hole 32A of the socket 32 described later. The spherical body portion 31 </ b> A is sandwiched from both the left and right sides by the recessed portion 33 </ b> B of the receiving portion 33 and the stepped portion 34 </ b> B of the pressing portion 34.

  The shape of the socket 32 is the same as the socket 22 of the first ball joint 2. The inner diameter of the socket 32 is substantially the same as the outer diameter of the cylindrical portion 62 of the connecting member 6. A screw thread is formed on the left end portion of the inner surface of the socket 32. This screw thread is screwed into a screw thread formed on the outer surface of the cylindrical portion 62. As a result, the socket 32 is connected to the connection member 6. The spherical body portion 31 </ b> A, the receiving portion 33, and the presser portion 34 of the ball stud 31 are accommodated in a space surrounded by the cylindrical portion 62 and the socket 32. The wall portion 321 and the hole 32A of the socket 32 correspond to the wall portion 221 and the hole 22A of the socket 22. The diameter of the hole 32A is substantially the same as the diameter of the opening 34A of the pressing portion 34. The inner end portion of the wall portion 321 contacts the outer surface of the right end portion of the second cylindrical portion 342 of the presser portion 34. The rod portion 31B of the ball stud 31 is inserted into the hole 32A.

  In a state where the socket 32 is screwed into the cylindrical portion 62 of the connecting member 6, the inner surface of the hole 32 </ b> A of the wall portion 221 of the socket 32 pushes the presser portion 34 inward. The second cylindrical portion 342 of the presser portion 34 is deformed so that the inner diameter of the right end portion is reduced, and the inner surface of the opening 34 </ b> A of the second cylindrical portion 342 is in close contact with the spherical body portion 31 </ b> A of the ball stud 31. The wall portion 221 of the socket 32 pushes the presser portion 34 toward the left side. The spherical body portion 31 </ b> A of the ball stud 31 that is in contact with the inner surface of the opening 34 </ b> A of the second cylindrical portion 342 of the pressing portion 34 is pressed by the pressing portion 34, moves to the left side, and is pressed against the receiving portion 33. As a result, the state in which the spherical portion 31A is sandwiched between the left and right sides by the receiving portion 33 and the pressing portion 34 is maintained.

  The distance between the bottom portion 621 of the cylindrical portion 62 and the wall portion 321 of the socket 32 varies depending on the degree of screwing of the socket 32 to the cylindrical portion 62. Depending on the distance between the bottom 621 and the wall 321, the force with which the receiving portion 33 and the pressing portion 34 sandwich the spherical portion 31 </ b> A changes. In the present embodiment, it is assumed that the degree of screwing of the socket 32 to the cylindrical portion 62 is adjusted in advance so that the spherical portion 31 </ b> A can move with respect to the receiving portion 33 and the holding portion 34. In this case, as shown in FIG. 9, the ball stud 31 can be rotated in the direction indicated by the arrow 3A around the virtual line 312 extending radially from the center 311 of the spherical body portion 31A. In addition, the ball stud 31 is within a range where the bar portion 31B does not contact the opening 34A of the presser portion 34, that is, within a range surrounded by a virtual line 314 connecting the center 231 and the inner end of the wall portion 321. It becomes possible to move in the direction indicated by. When the ball stud 31 moves in the direction indicated by the arrows 3A and 3B, the inner surface of the opening 34A of the second cylindrical portion 342 of the pressing portion 34 and the spherical portion 31A slide with each other, and the spherical portion 31A and the receiving portion The respective surfaces of the 33 with the recess 33B slide on each other.

  The movement in this case is a rotational movement around two axes (for example, a first axis extending in the left-right direction and a second axis extending in the up-down direction) orthogonal to the virtual line 312 and orthogonal to each other. Equivalent to. If the left-right direction in FIG. 9 is the X-axis, the front-rear direction is the Y-axis, and the up-down direction is the Z-axis, the movement around the virtual line 312 is the rotation Xθ around the X-axis, and the movement within the conical surface 314 is around the Y-axis. This is expressed as a combination of the rotation Yθ and the rotation Zθ around the Z axis. That is, like the first ball joint 2, the second ball joint 3 can move the ball stud 31 with three degrees of freedom.

  Hereinafter, the total area of the surfaces that slide when the ball stud 31 of the second ball joint 3 rotates is referred to as “second contact area” and is expressed as “S2”. The average static friction coefficient on the sliding surface is referred to as “second friction coefficient” and is expressed as “k2”. The average static frictional force on the sliding surface is called “second frictional force”, and the magnitude of the second frictional force is expressed as “F2”. The average radius of the ball portion 31A of the ball stud 31 is referred to as a “second average radius” and is expressed as “r2”. The rotation of the ball stud 31 of the second ball joint 3 is referred to as “the second ball joint 3 rotates”.

  In the above, the second contact area S2 and the third contact area S3 are substantially the same. The second contact area S2 and the third contact area S3 are larger than the first contact area S1 (S1 <S2, S1 <S3). Further, the second friction force F2 is larger than the first friction force F1, and the third friction force F3 is larger than the first friction force F1 (F1 <F2, F1 <F3). Further, the second friction coefficient k2 is larger than the first friction coefficient k1, and the third friction coefficient k3 is larger than the first friction coefficient k1 (k1 <k2, k1 <k3).

<Use example of HMD1>
An example of a usage example of the HMD 1 will be described. First, the user fixes the wearing tool 8 of the HMD 1 to the head. The user has the image display device 11 and the connection tool 9 and adjusts the position so that the half mirror 14 is arranged in front of the left eye. At this time, the first ball joint 2 can move the connection tool 9 with respect to the mounting tool 8 with three degrees of freedom. Further, the second ball joint 3 can move the image display device 11 with respect to the connector 9 with three degrees of freedom. That is, the first ball joint 2 and the second ball joint 3 can move the image display device 11 with six degrees of freedom with respect to the mounting tool 8. In a three-dimensional space, if there are six degrees of freedom, all the motions of the rigid body can be expressed. For this reason, the user can appropriately arrange the image display device 11 in a desired orientation at a desired position in front of the left eye.

<Relationship between first moment and second moment>
Referring to FIG. 11, a case where the user performs an operation to rotate the operation member 15 to adjust the focus after the adjustment of the position of the image display device 11 is completed will be illustrated. In response to the user operating the operation member 15, the operation member 15 rotates about the rotation shaft 15A. At this time, the force or moment applied to the operation member 15 to rotate the operation member 15 also acts on the image display device 11 at the same time. FIG. 11 illustrates a coordinate system in which the operation member 15 arranged in parallel with the XY plane rotates about the Z axis as the rotation axis 15A. At this time, the moment that the user applies to the operation member 15 is referred to as “operation moment”, and the magnitude thereof is expressed as “M0”. Applying the operating moment M0 is equivalent to applying a force of magnitude F1 at the position of the first average radius r1 from the rotation axis 15A in the XY plane. The force having the magnitude of F1 is referred to as “operation force”. F1 is represented by the following equation (1).
F1 = M0 / r1 (1)

Further, the image display device 11 is held by the connector 9 by the second ball joint 3. A part of the operating moment applied to the operating member 15 acts in the direction in which the second ball joint 3 is rotated. Specifically, it is as follows. As shown in FIG. 11, a straight line connecting the intersection (the origin of the coordinate system of FIG. 11) between the rotation axis 15A of the operation member 15 and the XY plane and the center 311 of the spherical portion 31A of the second ball joint 3 is The angle between the Z ′ axis and the Z axis (the rotation axis 15A of the operating member 15) is θ1. At this time, the moment applied to the second ball joint 3 as a result of operating the operation member 15 is referred to as “first moment”, and the magnitude thereof is expressed as “M1”. In this case, M1 is represented by the following equation (2).
M1 = M0 × cos θ1 (2)

  That is, the magnitude M1 of the first moment to rotate the second ball joint 3 changes according to the positional relationship between the operation member 15 and the second ball joint 3, and the ball stud 31 of the second ball joint 3 is changed. When the center 311 of the spherical portion 31A is on the XY plane, the minimum value 0 (cos θ1 = 0) is taken, and when the center 311 is on the Z axis, the maximum value M0 (cos θ1 = 1) is taken.

On the other hand, the application of the first moment M1 to the second ball joint 3 is equivalent to the application of the force M1 / r2 on the surface of the spherical portion 31A of the ball stud 31 of the second ball joint 3. M1 / r2 is represented by the following equation (3) based on the relationship of equation (2).
M1 / r2 = (M0 × cos θ1) / r2 (3)

  When this force M1 / r2 exceeds the second frictional force (magnitude F2) that is the static frictional force of the second ball joint 3, relative movement occurs between the spherical portion 31A of the ball stud 31 and the receiving portion 33. The second ball joint 3 changes the position of the image display device 11 with respect to the connection tool 9.

  As is clear from the above discussion, the first moment M1 is always 0 when cos θ1 is 0. In this case, regardless of the magnitude of the second frictional force F2 of the second ball joint 3, the spherical portion 31A of the ball stud 31 of the second ball joint 3 and the receiving portion 33 do not move relative to each other. Cos θ1 does not become 0 when the Z axis and the Z ′ axis are not orthogonal, that is, when the Z axis and the Z ′ axis have components parallel to each other.

  Here, as described above, the magnitude F2 of the second frictional force is larger than the magnitude F1 of the first frictional force (F1 <F2). For this reason, the force M1 / r2 (= (M0 × cos θ1) / r2) is smaller than the static friction force F2 of the second ball joint 3. Therefore, for example, even when the user directly operates and rotates the operation member 15 without fixing the position of the housing 12 of the image display device 11, the movement of the image display device 11 with respect to the connection tool 9 is the second ball. It is suppressed by the joint 3. For this reason, the position of the image display device 11 with respect to the connection tool 9 does not move before and after the operation of the operation member 15 and is maintained at a desired position in front of the user's left eye.

The moment required to move the position of the image display device 11 relative to the connector 9 by the second ball joint 3 is referred to as “second moment”, and the magnitude thereof is expressed as “M2” (= F2 × r2). In this case, since the relationship of “(M1 / r2) <(M2 / r2)” is established, the following equation (4) can be derived.
M1 <M2 (4)
That is, in HMD1, since the second moment M2 is larger than the first moment M1, even when the operating member 15 is operated by the operating force F1, the spherical portion 31A of the ball stud 31 of the second ball joint 3 The second ball joint 3 does not move relative to the receiving portion 33, and the position of the image display device 11 is not changed.

<Relationship between third moment and fourth moment>
The image display device 11 is held by the mounting tool 8 by the first ball joint 2 via the connection tool 9 and the second ball joint 3. A part of the operation moment applied to the operation member 15 acts in the direction in which the first ball joint 2 is rotated. Specifically, it is as follows. As shown in FIG. 12, a straight line connecting the intersection (the origin of the coordinate system in FIG. 12) between the rotation axis 15A of the operation member 15 and the XY plane and the center 211 of the spherical portion 21A of the first ball joint 2 is Z. The angle between the ″ axis and the Z ″ axis and the Z axis is φ1. At this time, the moment applied to the first ball joint 2 in response to the operation of the operation member 15 is referred to as “third moment”, and the magnitude thereof is referred to as “M3”. In this case, M3 is represented by the following equation (5).
M3 = M0 × conφ1 (5)

  That is, the magnitude M3 of the third moment for rotating the first ball joint 2 changes according to the positional relationship between the operating member 15 and the first ball joint 2, and the ball stud 21 of the first ball joint 2 is changed. When the center 211 of the spherical portion 21A is on the XY plane, the minimum is 0 (cos φ1 = 0), and when the center 211 of the spherical portion 21A of the ball stud 21 of the first ball joint 2 is on the Z axis, the maximum M0 (cos φ1 = 1).

On the other hand, the application of the third moment to the first ball joint 2 is equivalent to the application of the force M3 / r3 on the surface of the sphere 21A of the ball stud 21 of the first ball joint 2. M3 / r3 is represented by the following equation (6) based on the relationship of equation (5).
M3 / r3 = (M0 × cosφ1) / r3 (6)

  When this force M3 / r3 exceeds a third frictional force (size F3) that is a static frictional force of the first ball joint 2, a relative movement occurs between the spherical portion 21A of the ball stud 21 and the receiving portion 23. . In this case, the first ball joint 2 changes the position of the image display device 11 with respect to the mounting tool 8 by changing the position of the connection tool 9 with respect to the mounting tool 8.

  As is clear from the above discussion, when cos φ1 is 0, the third moment M3 is always 0. In this case, the spherical portion 21A of the ball stud 21 of the first ball joint 2 and the receiving portion 23 do not move relative to each other regardless of the magnitude of the third friction force F3 of the first ball joint 2. The case where cos φ1 does not become 0 is when the Z axis and the Z ″ axis are not orthogonal, that is, when the Z axis and the Z ″ axis have components parallel to each other.

  Here, as described above, the magnitude F3 of the third friction force is larger than the magnitude F1 of the first friction force (F1 <F3). Therefore, the force M3 / r3 (= (M0 × cos φ1) / r3) is smaller than the static friction force F3 of the first ball joint 2. Therefore, for example, even when the user operates the operation member 15 and rotates it directly without fixing the position of the housing 12 of the image display device 11, the movement of the image display device 11 with respect to the mounting tool 8 is performed by the first ball. It is suppressed by the joint 2. For this reason, the position of the image display device 11 with respect to the mounting tool 8 does not move before and after the operation with respect to the operation member 15 and is maintained at a position desired by the user.

The moment required to move the position of the image display device 11 with respect to the mounting tool 8 by the first ball joint 2 is referred to as “fourth moment”, and the magnitude thereof is represented as “M4” (= F3 × r3). In this case, since the relationship “(M3 / r3) <(M4 / r3)” is established, the following equation (7) can be derived.
M3 <M4 (7)
That is, in the HMD 1, the fourth moment M4 is larger than the third moment M3. Therefore, even when the operating member 15 is operated by the operating force F1, the spherical portion 21A of the ball stud 21 of the first ball joint 2 The first ball joint 2 does not move relative to the receiving portion 23, and the position of the image display device 11 is not changed.

<Main functions and effects of this embodiment>
As described above, the HMD 1 enables the user to adjust the position of the image display device 11 by allowing the position of the image display device 11 relative to the connection tool 9 to be moved by the second ball joint 3. In the HMD 1, the second ball joint 3 causes the connection tool 9 to be connected to the connector 9 rather than the magnitude M 1 of the first moment acting on the second ball joint 3 when the operation member 15 provided in the image display device 11 is operated. On the other hand, the magnitude M2 of the second moment necessary for moving the image display device 11 is larger. In this case, even if a force corresponding to the operation on the operation member 15 acts on the image display device 11, the movement of the image display device 11 with respect to the connection tool 9 is suppressed by the second ball joint 3. The position of the image display device 11 with respect to the connection tool 9 is difficult to shift before and after the operation on the operation member 15. Therefore, even when the user operates the operation member 15 after arranging the image display device 11 at a desired position, it is not necessary to readjust the position of the image display device 11 after the operation. For this reason, the user can continue to use the HMD 1 with the image display device 11 placed at a desired position.

  The HMD 1 has a magnitude relationship (M1 <M2) between the magnitude M1 of the first moment and the magnitude M2 of the second moment (M1 <M2), the first contact area S1, the second contact area S2, the first friction coefficient k1, and the second moment. It is defined based on the friction coefficient k2. Thereby, the HMD 1 suppresses the movement of the image display device 11 with respect to the connection tool 9 by the second ball joint 3. For this reason, HMD1 does not need to newly provide the member for suppressing the movement of the image display apparatus 11 with respect to the connection tool 9. FIG. Accordingly, the HMD 1 can simplify the configuration of the HMD 1 while suppressing the image display device 11 from moving in response to the operation of the operation member 15.

  The first ball joint 2 can move the connection tool 9 with respect to the mounting tool 8 with three degrees of freedom. For this reason, HMD1 can suppress that the image display apparatus 11 moves with respect to the connection tool 9 at the time of operation of the operation member 15, enabling the fine position adjustment of the image display apparatus 11 by a user.

  An O-ring 133 is interposed between the groove 132 provided in the front wall portion 13 </ b> A of the first housing 13 of the image display device 11 and the protruding portion 151 of the operation member 15. The O-ring 133 is sandwiched between the protruding portion 151 of the operation member 15 and the groove 132 of the front wall portion 13A. As a result, the HMD 1 can suppress the entry of water droplets, dust, and the like into the inside of the housing 12 through the hole 131 provided in the housing 12 by the O-ring 133. Further, the HMF 1 can easily realize the adjustment of the HMD 1 to satisfy the relationship of F1 <F2 by making the second contact area S2 larger than the first contact area S1. Therefore, the HMD 1 can easily prevent the position of the image display device 11 when operating the operation member 15 from being easily shifted with a simple configuration.

  In addition to the second ball joint 3, the HMD 1 further includes a first ball joint 2 that can be held by moving the position of the connection tool 9 relative to the mounting tool 8. Since the movement of the image display device 11 with respect to the mounting tool 8 is realized by the first ball joint 2 and the second ball joint 3, compared to the case where the image display device 11 is moved only by the second ball joint 3. The degree of freedom of movement of the image display device 11 can be increased. Specifically, the second ball joint 3 can move the image display device 11 with respect to the connector 9 with three degrees of freedom. That is, the first ball joint 2 and the second ball joint 3 can move the image display device 11 with six degrees of freedom with respect to the mounting tool 8. For this reason, the user can appropriately arrange the image display device 11 in a desired orientation at a desired position in front of the left eye. Therefore, the HMD 1 can suppress the movement of the image display device 11 with respect to the connection tool 9 when the operation member 15 is operated while allowing the user to finely adjust the position of the holding unit.

  Further, it is necessary to move the position of the connection tool 9 relative to the mounting tool 8 by the first ball joint 2 rather than the magnitude M3 of the third moment acting on the first ball joint 2 when the operating member 15 is operated. The magnitude of the fourth moment M4 becomes larger. In this case, even if a force corresponding to the operation on the operation member 15 acts on the image display device 11, the movement of the image display device 11 with respect to the mounting tool 8 is suppressed by the first ball joint 2. The position of the image display device 11 with respect to the mounting tool 8 is difficult to shift before and after the operation on the operation member 15. Therefore, even when the operation member 15 is operated after the image display device 11 is arranged at a desired position, it is not necessary to readjust the position of the image display device 11 after the operation. For this reason, the user can continue to use the HMD 1 with the image display device 11 placed at a desired position.

  In the above, the second contact area S2 and the third contact area S3 are larger than the first contact area S1 (S1 <S2, S1 <S3). The second friction coefficient k2 and the third friction coefficient k3 are larger than the first friction coefficient k1 (k1 <k2, k1 <k3). For this reason, the second friction force F2 and the third friction force F3 are larger than the first friction force F1 (F1 <F2, F1 <F3). Accordingly, the magnitude M2 of the second moment can be easily made larger than the magnitude M1 of the first moment, and the magnitude M4 of the fourth moment can be easily made larger than the magnitude M3 of the third moment. Therefore, the HMD 1 can easily prevent the position of the image display device 11 with respect to the connection tool 9 and the position of the image display device 11 with respect to the mounting tool 8 during the operation of the operation member 15 with a simple configuration.

  In the HMD 1, the material of the O-ring 133 is made of fluoro rubber, so that the second friction force magnitude F2 and the third friction force magnitude F3 can be easily made larger than the first friction force magnitude F1. it can.

<Modification>
The present invention is not limited to the above embodiment, and various modifications can be made. Hereinafter, a modification of the present invention will be described with reference to FIG. In the modification, the HMD 1 has a first translation mechanism 4 that can translate and move instead of the first ball joint 2. The HMD 1 has a second translation mechanism 5 capable of translational movement instead of the second ball joint 3. The HMD 1 includes an operation member 161 instead of the operation member 15.

  The first translation mechanism 4 is provided outside the second portion 83 of the mounting tool 8. The first translation mechanism 4 includes a sliding part 41, a base part 42, and a connecting part 43. The sliding portion 41 is a plate-like member that covers the outer side, the upper side, the lower side, and the inner side of the second portion 83. The sliding portion 41 is movable along the second portion 83. The base 42 has a substantially rectangular parallelepiped shape. The base portion 42 is connected to a portion of the sliding portion 41 that covers the outside of the second portion 83. The connection part 43 is substantially rod-shaped. The connecting portion 43 extends from the right end of the base portion 42 to the right side. The right end of the connecting portion 43 is connected to the upper end of the connection tool 9. The 1st translation mechanism 4 can translate the connection tool 9 according to the sliding part 41 moving along the 2nd part 83 of the mounting tool 8 (arrow 4A). Hereinafter, the static friction force when the first translation mechanism 4 translates is referred to as “fourth force”, and the magnitude of the fourth force is referred to as “P4”.

  The second translation mechanism 5 is interposed between the connector 9 and the image display device 11. The second translation mechanism 5 has an arm part 51 and a connecting part 52. The arm part 51 is substantially rod-shaped. The arm part 51 can be immersed in a hole (not shown) formed in the connection tool 9 from the lower end upward. The arm portion 51 is movable along the hole of the connection tool 9. The position of the lower end of the arm part 51 moves according to the amount of the part of the arm part 51 that enters the hole of the connector 9. The connecting part 52 connects the lower end of the arm part 51 and the rear end of the image display device 11. The second translation mechanism 5 can translate the image display device 11 in accordance with the movement of the arm portion 51 along the hole of the connector 9 (arrow 5A). Hereinafter, the static friction force when the second translation mechanism 5 translates is referred to as “second force”, and the magnitude of the second force is referred to as “P2”.

  A long hole 162 extending in the left-right direction is provided in the front wall portion 13A of the first housing 13 of the housing 12. The operation member 161 is movable in the left-right direction along the elongated hole 162 (arrow 161A). A protrusion (not shown) that protrudes rearward is provided on the rear surface of the operation member 161. The protruding portion is connected to the lens unit 172. The lens unit 172 moves in the left-right direction according to the movement of the operation member 161. A rubber member (not shown) is sandwiched between the operation member 161 and the front wall portion 13A of the first housing 13 of the housing 12. The rubber member prevents water drops, dust, and the like from entering the inside of the housing 12 through the long hole 162. The material of the rubber member is fluororubber. As the operation member 161 moves in the left-right direction, the operation member 161 and the rubber member slide with each other. Hereinafter, the average static friction force on the surface of the operation member 161 that slides during operation is referred to as “first static friction force” as in the above embodiment, and the magnitude of the first friction force is expressed as “F1”. . F1 is smaller than the magnitude P2 of the second force and the magnitude P4 of the fourth force (F1 <P2, F1 <P4).

<Relationship between first force and second force>
In response to the user operating the operation member 161, the operation member 161 moves in the left-right direction. At this time, the force applied to the operation member 161 to move the operation member 161 acts on the image display device 11 at the same time. FIG. 14 illustrates a coordinate system in which the operation member 161 arranged in parallel with the XY plane moves along the X-axis direction. At this time, the force applied to the operation member 161 by the user is referred to as “operation force”. The magnitude F1 of the operating force corresponds to the magnitude of the first frictional force.

A part of the operation force applied to the operation member 161 acts in the direction in which the second translation mechanism 5 is translated. Specifically, it is as follows. As shown in FIG. 14, the translation direction of the second translation mechanism 5 is taken as the X ′ axis, and the angle formed by the X axis and the X ′ axis is taken as θ2. At this time, the force applied to the second translation mechanism 5 in response to the operation of the operation member 161 is referred to as “first force”, and the magnitude thereof is expressed as “P1”. In this case, P1 is expressed by the following equation (8).
P1 = F1 × cos θ2 (8)

  That is, the magnitude P1 of the first force that attempts to translate the second translation mechanism 5 changes according to the positional relationship between the operation member 161 and the second translation mechanism 5. When the second translation mechanism 5 translates in a direction orthogonal to the X axis, the minimum value is 0 (cos θ2 = 0). When the second translation mechanism 5 translates in a direction parallel to the X axis, the maximum value F1 (cos θ2 = 1).

When the magnitude P1 of the first force exceeds the magnitude P2 of the second force that is the static frictional force of the second translation mechanism 5, the second translation mechanism 5 changes the position of the image display device 11. In other words, even when the operation member 161 is operated by the operation force F1 when the magnitude P1 of the first force is smaller than the magnitude P2 of the second force, that is, when the relationship of the following expression (9) is satisfied. The second translation mechanism 5 does not change the position of the image display device 11.
P1 = (F1 × cos θ2) <P2 (9)

  Here, as described above, the magnitude P2 of the second force is larger than the magnitude F1 of the first frictional force (F1 <P2). Also, cos θ2 has a value of 1 or less. Therefore, in HMD1, the relationship of Formula (9) is satisfied. For this reason, in the HMD 1, when the image display device 11 is moved relative to the connection tool 9 rather than the magnitude P 1 of the first force acting on the second translation mechanism 5 in response to the operation member 161 being operated. The minimum necessary second force P2 is larger. For this reason, for example, even when the user directly operates and moves the operation member 161 in a state where the position of the housing 12 of the image display device 11 is not fixed, the movement of the image display device 11 with respect to the connection tool 9 is the second. It is suppressed by the translation mechanism 5. Accordingly, the position of the image display device 11 does not move before and after the operation of the operation member 161, and is maintained at a desired position in front of the user's left eye, as in the above embodiment in which the second ball joint 3 is used. .

<Relationship between third force and fourth force>
The image display device 11 is held by the mounting tool 8 by the first translation mechanism 4 via the connection tool 9 and the second translation mechanism 5. A part of the operation force applied to the operation member 161 acts in the direction in which the first translation mechanism 4 is translated. Specifically, it is as follows. As shown in FIG. 15, the translation direction of the first translation mechanism 4 is the X ″ axis, and the angle formed by the X axis and the X ″ axis is φ2. At this time, the force applied to the first translation mechanism 4 in response to the operation of the operation member 161 is referred to as “third force”, and the magnitude thereof is expressed as “P3”. In this case, P3 is represented by the following equation (10).
P3 = F1 × conφ2 (10)

  That is, the magnitude P3 of the third force that attempts to translate the first translation mechanism 4 changes according to the positional relationship between the operation member 161 and the first translation mechanism 4. When the first translation mechanism 4 moves in a direction perpendicular to the X axis, the minimum value is 0 (cos φ2 = 0), and when the first translation mechanism 4 translates in a direction parallel to the X axis, the maximum value F1 (cos φ2 = 1). It becomes.

When the magnitude P3 of the third force exceeds the magnitude P4 of the fourth force that is the static frictional force of the first translation mechanism 4, the first translation mechanism 4 changes the position of the connection tool 9 with respect to the mounting tool 8. . Note that the position of the image display device 11 with respect to the mounting tool 8 is also changed according to the change in the position of the connection tool 9 with respect to the mounting tool 8. In other words, when the magnitude P3 of the third force is smaller than P4, that is, when the relationship of the following expression (11) is satisfied, even when the operating member 161 is operated by the operating force F1, the first translation mechanism 4 Does not change the position of the image display device 11 with respect to the wearing tool 8.
P3 = (F1 × cos φ2) <P4 (11)

  Here, as described above, the fourth force magnitude P4 is larger than the first frictional magnitude F1 (F1 <P4). Also, cos φ2 has a value of 1 or less. Therefore, in HMD1, the relationship of Formula (11) is satisfied. For this reason, it is necessary to move the image display device 11 with respect to the wearing tool 8 rather than the third force P3 acting on the second translation mechanism 5 in response to the operation member 15 being operated. The magnitude of the four forces P4 becomes larger. For this reason, similarly to the above-described embodiment, for example, even when the user operates the operation member 15 directly without moving the position of the housing 12 of the image display device 11 and moves the image display device 11 directly, The position of 11 does not move. For this reason, the HMD 1 can continuously hold the image display device 11 at a position desired by the user by suppressing the image display device 11 from moving in response to an operation on the operation member 15.

  The HMD 1 may have a first translation mechanism 4 instead of the first ball joint 2 and the second ball joint 3 as it is. That is, the connection tool 9 may translate relative to the mounting tool 8, and the image display device 11 may rotate relative to the connection tool 9. On the other hand, the HMD 1 may have a configuration including the second translation mechanism 5 instead of the second ball joint 3 and the first ball joint 2 as it is. That is, the connection tool 9 may rotate with respect to the mounting tool 8 and the image display device 11 may translate with respect to the connection tool 9.

  In the above, the operation member 15 was rotatable around the rotating shaft 15A. The operation member 15 can adjust the focus by moving the optical system 17 in the left-right direction according to the rotation. Further, the operation member 161 was able to translate along the XY plane. On the other hand, the HMD 1 may be able to adjust the focus with another operation member. For example, the operation member may be a push button or the like. The operation member 15 may be used for purposes other than focus adjustment. For example, the operation member 15 may be used for performing various settings of the HMD 1. The material of the O-ring 133 may not be a fluororesin. The HMD 1 may prevent water droplets and dust from entering through the hole 131 through which the operation member 15 is inserted by a member different from the O-ring 133. For example, a cover that covers the entire operation member 15 from the outside may be provided on the front wall portion 13 </ b> A of the housing 12. In this case, the HMD 1 may not have the O-ring 133. When the HMD 1 does not have the O-ring 133, the operation member 15 comes into contact with the groove 132. In this case, the groove 132 may be coated with a fluororesin.

  In the above, the 1st ball joint 2 and the 2nd ball joint 3 were used in the state which has three degrees of freedom, respectively. On the other hand, at least one of the first ball joint 2 and the second ball joint 3 may be used in a state having a degree of freedom of less than 3 by adjusting the degree of screwing of the socket to the cylindrical portion. . For example, in the first ball joint 2, the movement of the pressing portion 24 with respect to the socket 22 may be restricted in accordance with the degree of screwing of the socket 22 with respect to the second cylindrical portion 72B being strengthened. In this case, the movement of the presser portion 24 with respect to the socket 22 is restricted. In this case, the movement of the ball stud 21 in the direction indicated by the arrow 2B (see FIG. 7) is restricted. That is, the degree of freedom of the first ball joint 2 is reduced to two. The HMD 1 may be used with the first ball joint 2 as described above.

  In the above, the first contact area S1, the second contact area S2, and the third contact area S3 may be substantially the same. The first contact area S1 may be larger than the second contact area S2 and the third contact area. Both the second friction force F2 and the third friction force F3 may be substantially the same as the first friction force F1. The first friction force F1 may be greater than the second friction force F2 and the third friction force F3. Both the second friction coefficient k2 and the third friction coefficient k3 may be substantially the same as the first friction coefficient k1. The first friction coefficient k1 may be larger than the second friction coefficient k2 and the third friction coefficient k3. The rear surface of the operation member 15 may be polished so as to reduce the surface roughness.

  In the HMD 1, the connection tool 9 may be fixed to the mounting tool 8. In this case, the first ball joint 2 may not be provided between the connection tool 9 and the mounting tool 8. Further, the upper end of the connection tool 9 may be directly connected to the glasses or hat worn by the user of the HMD 1. In this case, the HMD 1 does not have to include the wearing tool 8 and the first ball joint 2.

<Others>
The image unit 18 is an example of the “display unit” in the present invention. The housing 12 of the image display device 11 is an example of the “holding unit” in the present invention. The operation member 15 is an example of the “operation unit” in the present invention. The connection tool 9 is an example of the “first support portion” in the present invention. The second ball joint 3 is an example of the “first adjusting portion” in the present invention. The O-ring 133 is an example of the “elastic member” in the present invention. The mounting tool 8 is an example of the “second support portion” in the present invention. The first ball joint 2 is an example of the “second adjusting portion” in the present invention. The rear surface of the operation member 15 and the front surface of the O-ring 133 are an example of “a plurality of first surfaces” in the present invention. The surface of the spherical portion 31A of the second ball joint 3 and the inner surface of the recess 33B of the receiving portion 33 are examples of the “plurality of second surfaces” in the present invention.

1: HMD
2: 1st ball joint 3: 2nd ball joint 8: Mounting tool 9: Connection tool 11: Image display apparatus 12: Housing | casing 14: Half mirror 15: Operation member 15A: Rotating shaft 18: Image unit 21: Ball stud 21A : Sphere part 23: Receiving part 31: Ball stud 31A: Sphere part 33: Receiving part 132: Groove 133: O-ring

Claims (11)

A holding unit having a display unit for displaying an image;
An operation unit provided on a surface of the holding unit;
A first support part for supporting the holding part;
A first adjustment unit that is connected between the first support unit and the holding unit and that can be held by moving a position of the holding unit relative to the first support unit;
The direction of the force acting on the holding unit when the operation unit is operated and the direction in which the holding unit can be moved by the first adjusting unit have components parallel to each other,
Rather than the magnitude of the first moment acting on the first adjustment unit when the operation unit is operated, the first adjustment unit needs to move the position of the holding unit relative to the first support unit. 2. A head mounted display characterized in that the magnitude of two moments is larger in all directions in which the holding part can be moved by the first adjusting part. The first adjustment unit includes:
The head mounted display according to claim 1, wherein the position of the holding portion can be moved with three or more degrees of freedom with respect to the first support portion. The first adjustment unit includes a sphere unit and a receiving unit that slide relative to each other in accordance with the position of the holding unit with respect to the first support unit being moved.
The operation unit is provided to be rotatable about a predetermined rotation axis with respect to the holding unit,
An annular member interposed between the surface of the holding portion and the operation portion, further comprising an elastic member through which the rotating shaft passes through the annular interior;
The second contact area between the spherical body part and the receiving part of the first adjustment part is larger than a first contact area between the operation part and the elastic member. Head mounted display. The first support part supports the holding part on one end side,
A second support connected to the other end of the first support;
A second adjustment unit connected between the first support unit and the second support unit, the second adjustment unit capable of moving and holding the position of the first support unit with respect to the second support unit;
The direction of the force acting on the holding part when the operation part is operated and the direction in which the first support part can be moved by the second adjustment part have components parallel to each other,
Necessary for moving the position of the first support part relative to the second support part by the second adjustment part rather than the magnitude of the third moment acting on the second adjustment part when the operation part is operated. 4. The head mounted display according to claim 1, wherein the magnitude of the fourth moment is larger in all directions in which the first support portion can be moved by the second adjustment portion. 5. . A holding unit for displaying an image;
An operation unit provided on a surface of the holding unit;
A first support part for supporting the holding part;
A first adjustment unit that is connected between the first support unit and the holding unit and that can be held by moving a position of the holding unit relative to the first support unit;
The direction of the force acting on the holding unit when the operation unit is operated and the direction in which the holding unit can be moved by the first adjusting unit have components parallel to each other,
Rather than the magnitude of the first force acting on the first adjustment unit when the operation unit is operated, the first adjustment unit requires the first adjustment unit to move the position of the holding unit relative to the first support unit. The head mounted display characterized in that the magnitude of the two forces is larger in all directions in which the holding part can be moved by the first adjusting part.   The holding portion relative to the first support portion by the first adjusting portion, rather than a first friction force that is a static friction force between a plurality of first surfaces that slide relative to each other in response to the operation portion being operated. 6. The second frictional force, which is a static frictional force between a plurality of second surfaces that slide relative to each other in accordance with the movement of the position, is greater. 6. Head mounted display.   The head mounted display according to claim 6, wherein a second static friction coefficient of the plurality of second surfaces is larger than a first static friction coefficient of the plurality of first surfaces.   The head-mounted display according to claim 6 or 7, wherein a material of at least one of the plurality of first surfaces is a fluororesin. The first support part supports the holding part on one end side,
A second support connected to the other end of the first support;
A second adjustment unit connected between the first support unit and the second support unit, the second adjustment unit capable of moving and holding the position of the first support unit with respect to the second support unit;
The direction of the force acting on the holding unit when the operation unit is operated and the direction in which the first support unit can be moved by the second adjustment unit have components parallel to each other,
Necessary for moving the position of the first support part relative to the second support part by the second adjustment part rather than the magnitude of the third force acting on the second adjustment part when the operation part is operated. 6. The head mounted display according to claim 5, wherein the magnitude of the fourth force is greater in all directions in which the first support portion can be moved by the second adjustment portion. The operation unit is provided to be rotatable about a predetermined rotation axis with respect to the holding unit,
An annular elastic member interposed between the surface of the holding unit and the operation unit;
The head mounted display according to claim 1, wherein the rotation shaft passes through an opening of the elastic member.   The head mounted display according to claim 4 or 9, wherein the first adjustment unit and the second adjustment unit move the position of the holding unit with respect to the second support unit with six degrees of freedom. .

Images