JP5133925B2 - Head-mounted image display device - Google Patents

Description

  The present invention relates to a head-mounted image display device, and more particularly to a novel head-mounted image display device that can display a plurality of images in parallel.

  As a conventional head-mounted image display device, for example, a device that can be used in a mobile manner such as a headset type or a spectacle type has been proposed (see, for example, Patent Documents 1 and 2).

  FIG. 15 is a diagram showing a schematic configuration of a conventionally proposed headset-type head mounted image display device, where (a) is a front view, (b) is a side view, and (c) is a plan view. . This head-mounted image display device 100 is of the left eye type, and is a headset-type head support unit 101 held in the left ear of the observer M, and the head support unit 101 has a relay unit 102 and a holding unit. And a rod-shaped light guide unit 104 which is connected via the unit 103 and is held in the left eye visual field of the observer M. The rod-shaped light guide unit 104 includes an eyepiece optical unit 105 that is coupled to an end opposite to the holding unit 103 side. The head support unit 101, the relay unit 102, or the holding unit 103 incorporates a display element (not shown) such as a liquid crystal display element or an organic EL element that displays an image to be observed. The image light of the displayed image is emitted from the eyepiece optical unit 105 through the rod-shaped light guide unit 104. In addition, this structure is good also as a right eye type by comprising right-and-left reverse.

  The head-mounted image display device 100 illustrated in FIG. 15 moves the head support unit 101 to the left of the observer M so that the image light emitted from the eyepiece optical unit 105 enters the left eye pupil of the observer M. By holding in the ear and looking into the eyepiece optical unit 105 in that state, that is, by making the visual axis of the left eye substantially coincide with the outgoing optical axis of the eyepiece optical unit 105, the image displayed on the display element (not shown) An enlarged virtual image can be observed.

  FIG. 16 is a perspective view showing a schematic configuration of a conventionally proposed glasses-type head-mounted image display apparatus. This head-mounted image display device 110 is a right-eye type that is integrated with spectacles, and the spectacles for the right eye in the visual field of the observer's right eye through a spectacle frame 111 via a support part 112 and a holding part 113. It has a rod-shaped light guide 115 that is held near the front of the lens 114. The rod-shaped light guide 115 has an eyepiece optical unit 116 coupled to an end opposite to the holding unit 113 side. The spectacle frame 111 or the support unit 112 or the holding unit 113 incorporates a display element (not shown) such as a liquid crystal display element or an organic EL element that displays an image to be observed, and is displayed on the display element. The image light of the obtained image is emitted from the eyepiece optical unit 116 through the rod-shaped light guide unit 115.

  In the head-mounted image display device 110 shown in FIG. 16, the image light emitted from the eyepiece optical unit 116 enters the right eye pupil through the eyeglass lens 114 when the observer puts on the eyeglass frame 111. ing. Therefore, the observer puts on the eyeglass frame 111 and looks into the eyepiece optical unit 116, that is, makes the right eye's visual axis substantially coincide with the outgoing optical axis of the eyepiece optical unit 116 to display on the display element (not shown). An enlarged virtual image of the captured image can be observed.

  An eyeglass-type head-mounted image display device that can be attached to and detached from a normal eyeglass frame and is used in the same manner as in FIG. 16 has been proposed.

  FIG. 17 is a schematic diagram of an optical path of a conventional head-mounted image display device. FIG. 17A shows optical paths of image light emitted from the upper, central, and lower portions of the display element 117 at different angles. The image light from the display element 117 forms an image 120 on the retina of the eyeball 119 of the observer as if it is light from a distant display image by passing through an eyepiece lens 118 constituting an eyepiece optical unit. To do. Thereby, the observer can recognize as if the display image is displayed at a set distance (for example, 2 m away).

In the present application, in order to display the optical path diagram in an easy-to-understand manner, only the principal ray is illustrated as shown in FIG. 17B, and only the optical path on the optical axis is illustrated in FIGS. Yes.

Japanese translation of PCT publication No. 2003-502713 JP 2006-3879 A

  By the way, for example, in an information display, there is a need to view a lot of information on one screen at the same time. In addition, a larger display screen may be required to display graphic information and the like. However, in the conventional head-mounted image display device described above, there is only one eyepiece optical unit that emits image light, and information is displayed on one display screen by the one eyepiece optical unit. . Moreover, since the head-mounted image display device can be used on a mobile device, its display screen is relatively small, and therefore the amount of information displayed is relatively small. For this reason, the conventional head-mounted image display device may not sufficiently meet the need to display a large amount of information on a large screen and view it simultaneously, as in an information display.

  In particular, as disclosed in Patent Document 2, the width of the projection cross section in the visual axis direction of the eyepiece optical unit and the rod-shaped light guide unit positioned in the visual field of the observer is set to 4 mm or less, and the eyepiece optical unit and the rod-shaped light guide unit are arranged. When see-through is possible, the display screen becomes smaller, and it becomes difficult to display a lot of information and graphic information with one eyepiece optical unit.

  In order to solve this problem, it is conceivable to provide a plurality of eyepiece optical units and display information on a multi-screen. However, when one rod-shaped light guide unit is required for one eyepiece optical unit, when a plurality of eyepiece optical units are arranged, a plurality of rod-shaped light guide units corresponding to the rod-shaped light guide unit exist in the field of view. Thus, even if the conditions for see-through are satisfied, the amount of light that can enter the pupil may be reduced, or unevenness may occur in the field of view, which may reduce the user's comfort. Further, when the design is such that the rod-shaped light guides are moved out of the field of view when not in use, there is a design restriction that the rod-shaped light guides must be arranged so as not to interfere with each other.

  Accordingly, an object of the present invention made in view of such a point is to provide a head-mounted image display device that has excellent usability while displaying a plurality of screens and has few design restrictions without deteriorating mobility. There is.

The invention of the head mounted image display device according to claim 1, which achieves the above object,
A plurality of eyepiece optical units that emit image light to be displayed toward the corresponding eyeballs;
A rod-shaped light guide unit that holds the plurality of eyepiece optical units and guides the image light to the corresponding eyepiece optical unit;
Holding the rod-shaped light guide unit, and having a head mounting part that can be detachably mounted on the observer's head,
In the state where the head mounting unit is mounted on the observer's head, an image of the image light from the plurality of eyepiece optical units is displayed within the visual field of the left or right eyeball of the observer. As described above, the rod-shaped light guide is held.

The invention according to claim 2 is the head-mounted image display device according to claim 1,
The rod-shaped light guide unit is characterized in that the width of the projected cross section in the direction of the visual axis of the observer is equal to or smaller than the pupil diameter.

The invention according to claim 3 is the head-mounted image display device according to claim 1 or 2,
A part of the optical path of each image light overlaps in the rod-shaped light guide.

The invention according to claim 4 is the head-mounted image display device according to any one of claims 1 to 3,
The rod-shaped light guide unit is configured such that any one of the image lights has an optical axis substantially parallel to a longitudinal direction of the rod-shaped light guide unit.

The invention according to claim 5 is the head-mounted image display device according to any one of claims 1 to 4,
The rod-shaped light guide unit is configured such that any one of the image lights is reflected by an inner surface extending in the longitudinal direction of the rod-shaped light guide unit.

The invention according to claim 6 is the head-mounted image display device according to any one of claims 1 to 5,
The rod-shaped light guide unit includes an image light separating unit that reflects any one of the image lights and transmits the other image light.

The invention according to claim 7 is the head-mounted image display device according to claim 6,
The image light separating means is a half mirror.

The invention according to claim 8 is the head-mounted image display device according to claim 6,
The image light separation means has an air gap, and any one of the respective image lights is incident on the image light separation means at an angle that is totally reflected by the image light separation means, and is reflected. The image light is incident on and transmitted through the image light separating means at an angle smaller than the totally reflected angle.

The invention according to claim 9 is the head-mounted image display device according to claim 6,
The respective image lights have different wavelengths, and the image light separation means includes a dichroic mirror for separating the respective image lights.

The invention according to claim 10 is the head-mounted image display device according to claim 6,
The respective image lights have polarization directions different from each other, and the image light separation means includes a polarization separation element for separating the respective image lights.

The invention according to claim 11 is the head-mounted image display device according to any one of claims 6 to 10,
The rod-shaped light guide part has a first reflecting surface inclined with respect to the longitudinal direction at the light guide direction front end part,
Any one of the respective image lights reflected by the image light separating means is incident on any one of the plurality of eyepiece optical units, and any of the other image lights transmitted through the separating means One is configured to be reflected by the first reflecting surface and incident on another eyepiece optical unit.

The invention according to claim 12 is the head-mounted image display device according to any one of claims 1 to 11,
The rod-shaped light guide unit includes image light coupling means for reflecting any one of the respective image lights to the respective incident portions of the image light and transmitting other image light.

The invention according to claim 13 is the head-mounted image display device according to claim 12,
The rod-shaped light guide has a second reflecting surface inclined at the rear end portion in the light guide direction with respect to the longitudinal direction of the rod-shaped light guide, and is incident from substantially the same direction as any one of the image lights. The other image light is reflected by the reflecting surface and is incident on the coupling means.

  According to the present invention, the rod-shaped light guide unit holds a plurality of eyepiece optical units in a state where the head-mounted unit is mounted on the head of the observer, and the rod-shaped light guide unit corresponds to each image light. Since the light is guided to the eyepiece optical unit, a plurality of images can be displayed in the field of view of the observer using a single rod-shaped light guide unit. As a result, it is possible to provide a head-mounted image display device that has excellent usability while displaying a plurality of screens and has few design restrictions.

1 is a perspective view showing a schematic configuration of a head-mounted image display device according to a first embodiment of the present invention. It is a front view which shows the positional relationship of the rod-shaped light guide part shown in FIG. 1, and an eyeball. It is a horizontal sectional view which shows the outline of the optical system containing the rod-shaped light guide part shown in FIG. It is a figure explaining the see-through display of a head mounting | wearing type image display apparatus. It is a figure which shows the image of the display screen in the visual field by the head mounted image display apparatus which concerns on 1st Embodiment. It is a horizontal sectional view which shows the outline of the optical system containing the rod-shaped light guide part of the head mounted image display apparatus which concerns on 2nd Embodiment of this invention. It is a horizontal sectional view which shows the outline of the optical system containing the rod-shaped light guide part of the head mounted image display apparatus which concerns on 3rd Embodiment of this invention. It is a horizontal sectional view which shows the outline of the optical system containing the rod-shaped light guide part of the head mounted image display apparatus which concerns on 4th Embodiment of this invention. It is a horizontal sectional view which shows the outline of the optical system containing the rod-shaped light guide part of the head mounted image display apparatus which concerns on 5th Embodiment of this invention. It is a horizontal sectional view which shows the outline of the optical system containing the rod-shaped light guide part of the head mounted image display apparatus which concerns on 6th Embodiment of this invention. It is a horizontal sectional view which shows the outline of the optical system containing the rod-shaped light guide part of the head mounted image display apparatus which concerns on 7th Embodiment of this invention. It is a horizontal sectional view which shows the outline of the optical system containing the rod-shaped light guide part of the head mounted image display apparatus which concerns on 8th Embodiment of this invention. It is a horizontal sectional view which shows the outline of the optical system containing the rod-shaped light guide part of the head mounted image display apparatus which concerns on 9th Embodiment of this invention. It is a figure which shows the position of the display screen in the visual field by the head mounted image display apparatus which concerns on 9th Embodiment. It is a figure which shows schematic structure of the conventional headset type head mounted image display apparatus. It is a perspective view which shows schematic structure of the conventional spectacles type head mounted image display apparatus. It is a schematic diagram of an optical path of a conventional head-mounted image display device.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a perspective view showing a schematic configuration of a head-mounted image display device according to a first embodiment of the present invention. This head-mounted image display device 10 is a right-eye type integrated with glasses, and includes an eyeglass frame 11, an image emitting unit 12, a rod-shaped light guide unit 20, and an eyepiece optical unit 13 a held by the rod-shaped light guide unit 20. , 13b. The spectacle frame 11 constitutes a head mounting portion, and the image ejection portion 12 is held on the right temple 14 portion. In addition, the image emitting unit 12 is coupled to the rod-shaped light guide unit 20, and when viewed from the front of the eyeball 15 with the spectacle frame 11 attached, the rod-shaped light guide unit 20 is observed as shown in FIG. The rod-shaped light guide 20 is held horizontally so as to extend within the right eye visual field of the person.

  FIG. 3 is a horizontal sectional view schematically showing an optical system including the rod-shaped light guide unit 20. In the following description, the light guide direction of the image light of the rod-shaped light guide unit 20, that is, the left side in FIG. 3 is the front side, the opposite side, that is, the right side in FIG. The most rear portion is called a rear end portion. Further, the front side, that is, the lower side in FIG. 3 is called the eyeball side, and the opposite side, that is, the upper side in FIG. 3 is called the image side.

  First, a specific configuration of the rod-shaped light guide unit 20 will be described. The rod-shaped light guide unit 20 includes three members: a front light guide member 23, a main light member 24 including a hexahedral prism, and a rear end light guide member 25. This rod-shaped light guide 20 has a substantially quadrangular prism shape as a whole, and has a tip inclined surface 21 as a first reflecting surface configured as a mirror surface at the tip, and a rear end. The rear end inclined surface 22 is provided. Air gaps 26 and 27 are formed between the leading light guide member 23 and the leading light member 24 and between the leading light member 24 and the trailing light guide member 25 with the inclined boundary surfaces facing each other. ing. Further, the front light guide member 23, the main light guide member 24, and the rear light guide member 25 are made of a resin material or glass material having a high light transmittance, and are mutually positioned in a resin case, not shown. The relationship is fixed and stored so as not to be displaced. Furthermore, the width of the projection cross section of the rod-shaped light guide unit 20 including this case in the direction of the visual axis of the observer is set to a pupil diameter, that is, 4 mm or less to enable see-through display.

  Here, the see-through display will be briefly described. FIG. 4 is a vertical sectional view schematically showing the optical system of the head-mounted image display apparatus 10. For simplicity, the eyepiece optical unit 13 and the display element 16 are shown one by one. The image light 51 emitted from the display element 16 is emitted from the eyepiece optical unit 13 toward the eyeball 15 and forms a display image 50 in the visual field of the observer. On the other hand, the width of the projection cross section of the rod-shaped light guide 20 in the visual axis direction of the observer is made narrower than the pupil diameter of the eyeball 15, so that a distant object in the observer's field of view, for example, a front that is 2 m or more away The light 52 from the object passes through the periphery of the rod-shaped light guide 20 and enters the eyeball, and forms an image in a region overlapping the display image 51 on the retina. Therefore, the display image 51 is displayed as a see-through image superimposed on the background within the field of view of the observer.

  Next, the first display element 16a and the second display element 16b for displaying the first image light 51a and the second image light 51b, respectively, and the respective image lights 51a and 51b are emitted toward the eyeball 15. The configuration and arrangement of the first eyepiece optical unit 13a and the second eyepiece optical 13b to be performed will be described. The display elements 16a and 16b are configured to include, for example, an organic EL element or an LCD element, and the first display element 16a is disposed behind and in opposition to the rear end inclined surface 22 of the rear end light guide member 25. The second display element 16b is disposed on the rear end eyeball side of the main light member 24 so as to be opposed thereto. The eyepiece optical units 13a and 13b include, for example, an eyepiece lens, the first eyepiece optical unit 13a is coupled to the eyeball side of the distal end light guide member 23, and the second eyepiece optical unit 13b is a leading light member. The air gap 28 is arranged on the eyeball side of the distal end portion of 24.

  Next, an optical path through which the first image light 51a and the second image light 51b propagate will be described. It should be noted that the dimensions of each light guide member 23, 24, 25, the front inclined surface 21, the rear end inclined surface 22, the inclination angle of the boundary surface of each light guide member sandwiching the air gaps 26, 27, the display elements 16a, 16b and the contact. The tilt angles and the like of the eye optical units 13a and 13b are such that the image lights 51a and 51b emitted from the display elements 16a and 16b are directed toward the eyeball 15 of the observer of the head-mounted image display device 10 by an optical path described below. It is defined to be emitted.

  The first image light 51 a emitted from the first display element 16 a enters the rear end light guide member 25 from the rear end inclined surface 22 and then enters the boundary surface with the air gap 27. The incident angle of the first image light 51a with respect to the air gap 27 is smaller than the critical angle at the interface between the rear end light guide member 25 and the air gap 27. Therefore, the first image light is transmitted through the air gap 27. Is incident on the main light 24. Thereafter, the first image light 51 a propagates in the main light member 24 with an inclination in the longitudinal direction, is totally reflected by the inner side surface 30 on the eyeball side of the main light member 24, and is a boundary surface with the air gap 26. Is incident on. The incident angle of the first image light 51 a with respect to the air gap 26 is smaller than the critical angle. Therefore, the first image light 51 a passes through the air gap 26 and enters the tip light guide member 23. Further, the first image light 51a is reflected by the tip inclined surface 21, guided to the first eyepiece optical unit 13a, and emitted toward the observer's eyeball.

  On the other hand, the second image light 51 b emitted from the second display element 16 b enters the leading light member 24 from the rear end eyeball side of the leading light member 24 and enters the boundary surface with the air gap 27. The incident angle of the second image light 51b with respect to the air gap 27 is larger than the critical angle. Therefore, the second image light is reflected at the boundary surface with the air gap 27, and the light guide member 24 is guided in a bar shape. It propagates parallel to the longitudinal direction of the part 20. Thereafter, the second image light 51 b enters the boundary surface with the air gap 26. The incident angle of the second image light 51b with respect to the air gap 26 is larger than the critical angle. Therefore, the second image light 51b is reflected at the boundary surface with the air gap 27 and is incident on the leading end of the main light member 24. The light passes through the eyeball side surface, is guided to the second eyepiece optical unit 13b, and is emitted toward the observer's eyeball. The air gap 28 between the main light member 24 and the second eyepiece optical unit 13b is such that a part of the first image light 51a to be reflected by the inner side surface 30 is the main light member 24 and the second eyepiece light. This is to prevent the light transmitting member 24 from penetrating from the contact portion with the undergraduate 13b.

  The air gap 27 and the boundary surface between the leading light member 24 and the rear light guide member 25 facing each other across the air gap 27 constitute an image light coupling means, and the air gap 26 and the air gap 27, the boundary surface between the leading light guide member 23 and the main light member 24 facing each other constitutes image light separating means.

  With the above configuration, for example, as shown in FIG. 5, the head-mounted image display device 10 has the first display element 16a and the second display element 16b emitted from each of the first display element 16b and the viewer's field of view. The left image (first image) 50a and the right image (second image) 50b are formed by aligning the image light 51a and the second image light 51b in a horizontal direction on the retina of the eyeball 15 of the observer. Are displayed as two screens. In addition, since the width of the projection cross section (including the portion that obstructs the field of view, such as a case) of the rod-shaped light guide 20 in the visual axis direction is set to a pupil diameter or less, that is, 4 mm or less, the display image is a see-through image. be able to.

  As described above, according to the present embodiment, two eyepiece optical units 13a and 13b are provided in one rod-shaped light guide unit 20, and the rod-shaped light guide unit 20 is shared to correspond to the image lights 51a and 51b, respectively. Since the light is guided to the eyepiece optical unit, the two display images can be horizontally arranged and displayed in the observer's visual field. Moreover, since the width of the projection cross section of the rod-shaped light guide unit 20 in the visual axis direction of the observer is set to be equal to or smaller than the pupil diameter, the display image can be a see-through image. As a result, it is possible to obtain the advantages of excellent usability while using a plurality of screens and less design restrictions.

(Second Embodiment)
FIG. 6 is a horizontal sectional view showing an outline of an optical system including a rod-shaped light guide portion of the head-mounted image display device according to the second embodiment of the present invention. This head-mounted image display device is different from the first embodiment in the configuration of the rod-shaped light guide 20. The rod-shaped light guide part 20 of this Embodiment is comprised by the front-end | tip light guide member 23 and the leading light member 24, and the air gap 26 is formed among them. The tip light guide member 23 has a tip inclined surface 21 similar to the tip light guide member shown in FIG. In addition, the main light member 24 has a structure in which the rear side expands to the eyeball side as compared to the front side, and the first display element 16a and the first display element 16a are arranged in order from the eyeball side on the rear end portion where the main light member 24 expands. Two display elements 16b are spaced apart in the horizontal direction. Further, the first eyepiece optical unit 13 a is provided on the eyeball side of the tip light guide member 23, and the second eyepiece optical unit 13 b is provided on the tip part eyeball side of the main light member 24. Further, the material of the distal end light guide member 23 and the main light guide member 24, the storage method, the width of the projected cross section in the visual axis direction of the observer, and the like are the same as those of the light guide member of the first embodiment.

  Next, an optical path through which the first image light 51a and the second image light 51b propagate will be described. The first image light 51a and the second image light 51b emitted from the first display element 16a and the second display element 16b are incident on the main light member 24, and the inner surface of the main light member 24 is inside. It propagates without being reflected by the light and enters the boundary surface with the air gap 26. The first image light 51a is incident on the boundary surface with the air gap 26 at an incident angle smaller than the critical angle, is transmitted therethrough, is reflected by the tip inclined surface 21, and is incident on the first eyepiece optical unit 13a. It is guided and emitted toward the eyeball 15 of the observer. On the other hand, the second image light 51b is incident on the boundary surface with the air gap at an incident angle larger than the critical angle, and is totally reflected. The second image light totally reflected at the interface with the air gap 26 is guided to the second eyepiece optical unit 13b and emitted toward the eyeball 15 of the observer. As a result, the two display images are displayed as see-through images arranged horizontally in the viewer's field of view.

  As described above, according to the present embodiment, the first display element 16a and the second display element 16b can be disposed substantially adjacent to each other without providing the image light coupling portion. The entire configuration of the display device can be simplified.

(Third embodiment)
FIG. 7 is a horizontal sectional view showing an outline of an optical system including a rod-shaped light guide portion of a head-mounted image display device according to the third embodiment of the present invention. In this head-mounted image display device, the configuration of the rod-shaped light guide 20 is different from that of the second embodiment. The rod-shaped light guide unit 20 in the present embodiment includes a tip light guide member 23 and a main light member 24. The main light guide member 24 has a rod-like (prism-like) shape on the front side in the light guide direction, and has a structure in which only the rear side spreads to the eyeball side of the observer. Further, an air gap 26 is provided between the leading end light guide member 23 and the main light member 24. Further, the positions of the first display element 16a and the second display element 16b are switched, and the second display element 16b is arranged on the eyeball side of the first display element 16a.

  Next, an optical path through which the first image light 51a and the second image light 51b propagate will be described. The first image light 51a emitted from the first display element 16a propagates in the main light member 24 in parallel to the longitudinal direction, and enters the boundary surface with the air gap 26 at an incident angle smaller than the critical angle. The light passes through this, enters the distal end light guide member 23, is reflected by the distal end inclined surface 21, and is emitted from the first eyepiece optical unit 13a toward the eyeball 15 of the observer. On the other hand, the second image light 51 b emitted from the second display element 16 b is reflected by the inner surface 31 on the image side of the main light member 24 and then has an incident angle larger than the critical angle at the boundary surface with the air gap 26. And is reflected from the second eyepiece optical unit 13b and emitted toward the eyeball 15 of the observer. As a result, the two display images are displayed as see-through images arranged horizontally in the viewer's field of view. Note that the incident angle of the second image light 51b to the boundary surface of the air gap 26 is larger than that in the second embodiment, so that the optical path width that can be guided to the second eyepiece optical unit 13b is narrowed. For this reason, as compared with the second embodiment, the second display element having a narrow width is used in this embodiment, and the width of the second eyepiece optical unit is also reduced. Since other configurations and operations are substantially the same as those of the second embodiment, the same components are denoted by the same reference numerals, and description thereof is omitted.

  As described above, according to the present embodiment, since the bar-shaped light guide portion 20 spreads only on the rear side, the rod-shaped light guide portion in the observer's field of view as compared with the bar-shaped light guide portion in the second embodiment. The width of the light guide 20 in the image side direction can be further reduced, and the entire bar-shaped light guide 20 can be further reduced in weight.

(Fourth embodiment)
FIG. 8 is a horizontal sectional view showing an outline of an optical system including a rod-shaped light guide unit of a head-mounted image display device according to the fourth embodiment of the present invention. This head-mounted image display device is different from the third embodiment in the configuration of the rod-shaped light guide 20. The rod-shaped light guide 20 of the present embodiment is composed of a tip light guide member 23 and a main light member 24. Unlike the third embodiment, the main light guide member 24 has a rear side in the light guide direction spreading toward the image side. The second display element 16b is disposed on the image side of the first display element 16a. Further, a half mirror 29 is formed as an image light separating means between the tip light guide member 23 and the main light member 24. An air gap 28 is provided between the second eyepiece optical unit 13 b and the main light member 24.

  Next, an optical path through which the first image light 51a and the second image light 51b propagate will be described. The first image light 51a emitted from the first display element 16a propagates through the main light member 24 and enters the half mirror 29, and is partially reflected and partially transmitted. The first image light 51a that has passed through the half mirror 29 is reflected by the tip inclined surface 21, and is emitted toward the eyeball 15 of the observer from the first eyepiece optical unit 13a. On the other hand, the first image light 51a reflected by the half mirror 29 is not emitted in the eyeball direction because the optical path deviates.

  Further, the second image light 51b emitted from the second display element 16b propagates through the main light member 24, is reflected by the inner side surface 30 on the eyeball side, and then enters the half mirror 29, and a part thereof. Reflected and partially transmitted. The light reflected by the half mirror 29 enters the second eyepiece optical unit 13b through the air gap 28 and is emitted toward the eyeball 15 of the observer. The air gap 28 is provided so that a part of the second image light 51b does not pass through the second eyepiece optical unit 13b when entering the inner surface 30 from the display element 16b. On the other hand, the second image light 51b transmitted through the half mirror 29 is not emitted in the eyeball direction because the optical path deviates.

  As a result, the two display images are displayed as see-through images arranged horizontally in the viewer's field of view. Since other configurations and operations are substantially the same as those of the third embodiment, the same components are denoted by the same reference numerals and description thereof is omitted.

  According to the head-mounted image display device according to the present embodiment, the incident angle of the second image light 51b with respect to the half mirror 29 is such that the second image light in FIG. As shown in FIG. 8, since the width of the optical path of the second image light 51b can be secured, the optical path width of the second image light 51b that can be guided to the second eyepiece optical unit 13b is increased. be able to. Therefore, it is possible to display a larger second image in the observer's field of view as compared to the third embodiment.

  In the present embodiment, the half mirror 29 is used as the image light separating means, but the present invention is not limited to this. For example, a polarization separation film is formed on the inclined surface between the tip light guide member 23 and the main light member 24 instead of the half mirror 29, and the polarization state is changed on the output side of each of the display elements 16a and 16b, for example. The first image light 51a and the second image light 51b are separated from each other by disposing a polarizer to be disposed and making the polarization directions of the first image light 51a and the second image light 52b different by 90 °. You may make it isolate | separate with a film | membrane.

(Fifth embodiment)
FIG. 9 is a horizontal sectional view showing an outline of an optical system including a rod-shaped light guide portion of a head-mounted image display device according to a fifth embodiment of the present invention. In this head-mounted image display device, the configuration of the rod-shaped light guide unit 20 is different from that of the fourth embodiment. Unlike the rod-shaped light guide unit of FIG. 8, the rod-shaped light guide unit 20 of the present embodiment has a rear side of the leading light member 24 extending toward the eyeball side of the observer. In addition, the first display element 16a and the second display element 16b are arranged at the rear end portion of the main light member 24 in order from the eyeball side of the observer.

  Next, an optical path through which the first image light 51a and the second image light 51b propagate will be described. The first image light 51a emitted from the first display element 16a propagates in the rod-shaped light guide 20 from the widened portion of the rear eyeball toward the front side and the image side, and the inner side surface 31 and the eyeball side on the image side. Is reflected by the inner side surface 30 of the lens and further reflected by the tip inclined surface 21 and emitted from the first eyepiece optical unit 13a toward the eyeball 15 of the observer. Before and after reflection by the inner surface 30 on this optical path, the first image light passes through the half mirror 29 from the main light member 24 to the tip light guide member 23, and part of the light is reflected. The second image light reflected by the half mirror 29 is not emitted in the direction of the eyeball 15 because the optical path deviates.

  Further, the second image light 51b emitted from the second display element 16b propagates forward in the longitudinal direction in the main light member, is reflected by the half mirror 29, and is reflected by the second eyepiece optical unit 13b via the air gap 28. Is emitted toward the eyeball 15. Although a part of the image light 51b is transmitted through the half mirror 29, the image light is not emitted in the eyeball direction because the optical path is deviated. The air gap 28 is provided so that a part of the first image light 51 a does not transmit to the second eyepiece optical unit 13 b when entering the inner side surface 30.

  As a result, the two display images are displayed as see-through images arranged horizontally in the viewer's field of view. Since other configurations and operations are substantially the same as those of the fourth embodiment, the same reference numerals are assigned to substantially the same components, and the description thereof is omitted.

  According to the present embodiment, compared with the fourth embodiment, the spreading portion on the rear side of the rod-shaped light guide unit 20 is spread toward the observer's eyeball side in a state where it is applied to the spectacle frame. Since there is no portion extending to the image side, the image emitting unit 12 can be made less noticeable, and a head-mounted image display device excellent in portability and aesthetics can be configured.

  In the present embodiment, the half mirror 29 is used as the image light separating means, but the present invention is not limited to this. For example, a polarization separation film is formed on the inclined surface between the tip light guide member 23 and the main light member 24 instead of the half mirror 29, and the polarization state is changed on the output side of each of the display elements 16a and 16b, for example. The first image light 51a and the second image light 51b are separated from each other by disposing a polarizer to be disposed and making the polarization directions of the first image light 51a and the second image light 52b different by 90 °. You may make it isolate | separate with a film | membrane.

(Sixth embodiment)
FIG. 10 is a horizontal sectional view showing an outline of an optical system including a rod-shaped light guide unit of a head-mounted image display device according to a sixth embodiment of the present invention. This head-mounted image display apparatus is different from the first embodiment in the configuration of the optical system including the rod-shaped light guide unit 20. The rod-shaped light guide unit 20 according to the present embodiment includes a tip light guide member 23 and a main light member 24. The tip light guide member 23 and the main light guide member 24 are in contact with each other by an inclined surface, and a dichroic mirror 33 is formed on the boundary surface. The dichroic mirror 33 has a spectral characteristic that transmits red light and reflects blue light. The tip light guide member 23 has a tip inclined surface 21 at the tip portion. The tip inclined surface 21 is a mirror surface that totally reflects the image light that has propagated through the tip light guide member 23. Thereby, the rod-shaped light guide 20 as a whole has a substantially quadrangular prism shape having the tip inclined surface 21 at the tip. Further, the material of the distal end light guide member 23 and the main light guide member 24, the storage method, the width of the projected cross section in the visual axis direction of the observer, and the like are the same as those of the light guide member of the first embodiment.

  Further, in the present embodiment, the single display element 16 is disposed in the vicinity of the rear end portion of the main light member 24 with the emission surface facing the rear end surface 32. The display element 16 emits first image light of only red color and second image light of only blue color having different display contents from each other in a frame sequential manner. Further, the first eyepiece optical unit 13 a is disposed on the eyeball side of the distal light guide member 23, and the second eyepiece optical unit 13 b is disposed on the eyeball side of the distal end portion of the leading light member 24.

  Next, an optical path through which the first image light 51a and the second image light 51b propagate will be described. The red first image light 51 a and the blue second image light 51 b emitted from the display element 16 propagate forward in the longitudinal direction of the main light member 24 and enter the dichroic mirror 33. Here, the first image light 51 a passes through the dichroic mirror 33, enters the tip light guide member 23, is reflected by the tip inclined surface 21, enters the first eyepiece optical unit 13 a, and the eyeball 15 of the observer. It is emitted toward On the other hand, the second image light 51b is reflected by the dichroic mirror 33, enters the second eyepiece optical unit 13b, and is emitted toward the eyeball 15 of the observer.

  As a result, the two display images are displayed as see-through images arranged horizontally in the viewer's field of view. In this case, of the two display images displayed in the field of view, the left side is an image of only red and the right side is an image of only blue.

  As described above, according to the present embodiment, light having different frequencies emitted from the same display element 16 is used as the first image light 51a and the second image light 51b, and this is used as the dichroic mirror 33. Are separated from each other and emitted from the first eyepiece optical unit 13a and the second eyepiece optical unit 13b, respectively, so that the number of display elements is one and the image emitting unit can be configured simply. In addition, since it is not necessary to make the inclination of the optical path of the first image light 51a and the second image light 51b different, the rod-shaped light guide 20 is formed in a prismatic shape having no spreading portion on the image side or the eyeball side. Since it can do, the rod-shaped light guide part 20 can be made small and lightweight.

  In the present embodiment, the first image light 51a is red and the second image light 51b is blue. However, the present invention is not limited to this. The first image light 52a may be blue and the second image light 51b may be red, and light of a different color may be either or both of the first image light 51a and the second image light 51b. You may use for either. Also in this case, a dichroic mirror 33 having a spectral characteristic that transmits the first light and reflects the second light is used.

(Seventh embodiment)
FIG. 11 is a horizontal sectional view showing an outline of an optical system including a rod-shaped light guide unit of a head-mounted image display device according to a seventh embodiment of the present invention. This head-mounted image display device is different from the sixth embodiment in the configuration of the optical system including the rod-shaped light guide unit 20. The rod-shaped light guide 20 of the present embodiment includes a front light guide member 23, a main light member 24, and a rear end light guide member 25. The main light guide member 23 and the rear light guide member 25 and the front light guide member 23 and the main light guide member 24 are in contact with each other by an inclined surface, and p-polarized light is transmitted through the boundary surfaces. Polarization separation films 34 and 35 that reflect s-polarized light are formed.

  On the other hand, on the rear side of the rear end portion of the rod-shaped light guide portion 20, a display element 16a configured by an organic EL element that emits first image light facing the rear end light guide member 25, and the display A polarizer 41a is provided for converting the image light emitted from the element 16a into vertically polarized light (p-polarized light). Further, a display element 16b that emits the second image light 51b facing the side surface of the main light member 24 on the rear end image side of the rod-shaped light guide 20 and a second element that emits the display element 16b. A polarizer 41b that converts the image light 51b into horizontally polarized light (s-polarized light) is provided. Since other configurations are the same as those of the sixth embodiment, the same components are denoted by the same reference numerals, and the description thereof is omitted.

  With the configuration as described above, according to the present embodiment, the polarization state of the first image light 51a emitted from the display element 16a is changed by the polarizer 41a and is incident on the rear end light guide member 25 as p-polarized light. To do. Thereafter, the first image light 51a passes through the polarization separation film 34 and enters the main light member 24, and propagates in the longitudinal direction. Further, the first image light 51 a passes through the polarization separation film 35, enters the tip light guide member 23, is reflected by the tip inclined surface 21, enters the first eyepiece optical unit 13 a, and the observer's eyeball 15. It is emitted toward

  On the other hand, the polarization state of the second image light 51b emitted from the display element 16b is changed by the polarizer 41b and is incident on the rear end side surface of the leading light member 24 as s-polarized light. Thereafter, the second image light 51b is reflected by the polarization separation film 34, and propagates through the main light member 24 in the longitudinal direction in the same manner as the first image light. Thereafter, the second image light 51 b is reflected by the polarization separation film 35, enters the second eyepiece optical unit 13 b, and is emitted toward the eyeball 15 of the observer.

  As a result, the two display images are displayed as see-through images arranged horizontally in the viewer's field of view.

  As described above, according to the present embodiment, the optical paths of two image lights having different polarization states are overlapped using the polarization separation film 34 and propagated through the same guiding light member 24, thereby allowing other polarized light to propagate. Since the light is separated by the separation film 35 and emitted from the first eyepiece optical unit and the second eyepiece optical unit, respectively, the image emitting unit can have a simple configuration as in the sixth embodiment, and The rod-shaped light guide 20 can be reduced in size and weight. Furthermore, unlike the sixth embodiment in which images are separated by wavelength components, both display images can be made into color images.

  In addition, although the first image light 51a is p-polarized and the second image light 51b is s-polarized, the first image light 51a may be s-polarized and the second image light 51b may be p-polarized. In that case, as the polarization separation films 34 and 35, those which transmit p-polarized light and reflect s-polarized light are used.

  Further, as a modification of the present embodiment, LCD elements can be used as the display elements 16a and 16b in place of the organic EL elements. For example, when each LCD element emits image light polarized in the horizontal direction (s-polarized light), a half-wave plate is provided in place of the polarizer 41a, and the polarizer 41b is not provided. As a result, the image light 51 a emitted from the display element 16 a becomes p-polarized light when passing through the half-wave plate and enters the rear end light guide member 25. On the other hand, the image light 51b emitted from the display element 16b enters the main light member 24 as s-polarized light. The following operations and effects are the same as in the present embodiment. In this modification, the LCD element arranged as the display element 16a without using the half-wave plate is rotated 90 degrees while facing the rear end face 32, and the image light polarized in the vertical direction is obtained. You may make it radiate | emit.

(Eighth embodiment)
FIG. 12 is a horizontal sectional view showing an outline of an optical system including a rod-shaped light guide unit of a head-mounted image display device according to an eighth embodiment of the present invention. This head-mounted image display device is different from the seventh embodiment in the configuration of the optical system including the rod-shaped light guide 20. The rod-shaped light guide unit 20 of the present embodiment is configured by the tip light guide member 23 and the main light guide member 24, that is, unlike the rod-shaped light guide unit of FIG. In addition, the display element 16a configured by an organic EL element is opposed to the rear end surface 32 of the main light member 24, and a polarizer 41 that converts image light emitted from the display element 16a into vertically polarized light (p-polarized light). And a light rotation element 42 that switches the polarization direction of the polarized image light, for example, a polarization rotation element using liquid crystal (for example, TN liquid crystal). Since other configurations are the same as those of the seventh embodiment, the same components are denoted by the same reference numerals, and description thereof is omitted.

  With the configuration as described above, according to the present embodiment, the first image light and the second image light are emitted by causing the display element 16 to display the first image and the second image while switching them in the frame order. These are polarized in the vertical direction by the polarizer 41, and the polarization direction of the image light is switched by the light modulation element 42 in synchronization with the switching of the image by the display element 16. As a result, the first image light is p-polarized light and the second image light is s-polarized light, and sequentially enters the main light member 24 in a time division manner. Similarly to the seventh embodiment, the first image light and the second image light 51b incident on the main light guide member 24 are guided to the first eyepiece optical unit 13a and the second eyepiece optical unit 13b, respectively. It is emitted toward the eyeball 15 of the observer. As a result, the two display images are displayed as see-through images arranged horizontally in the viewer's field of view.

  As described above, according to the present embodiment, the first image light 51a and the second image light 51b are sequentially transmitted from one display element 16 provided at the rear end portion of the rod-shaped light guide unit 20. Since the polarization state is changed in synchronization with the emission of the image light by using the polarizer 41 and the light modulation element 42, the rod-shaped light guide unit 20 is added to the effect of the seventh embodiment. There is no need to provide a display element and a polarizer on the side surface, and the image emitting unit for storing the rod-shaped light guide 20 and the display element 16 can be reduced in size and weight. Therefore, the entire head-mounted image display device can be made small and lightweight.

  Note that the polarizer 41a converts the image light emitted from the display element 16a into vertically polarized light (p-polarized light), but converts the image light emitted from the display element 16a into horizontally polarized light (s-polarized light). It may be used. In that case, a material that transmits s-polarized light and reflects p-polarized light is used for the polarization separation film 35.

  As a modification of the present embodiment, an LCD element can be used as the display element 16 instead of the organic EL element. In that case, since the image light emitted from the LCD element is linearly polarized in one direction, the polarizer 41 is not provided, and the image light emitted from the display element 16 is directly incident on the light modulation element 42. As a result, the first image and the second image are displayed on the display element 16 while being switched in the frame order to emit the first image light and the second image light, and light modulation is performed in synchronization with the switching of the images. The element 42 can switch the polarization direction of the image light.

(Ninth embodiment)
FIG. 13 is a perspective view showing a schematic configuration of a head-mounted image display device according to the ninth embodiment of the present invention. The head-mounted image display device 10 is a right-eye type that is integrated with glasses. In the head-mounted image display device 10, the rod-shaped light guide unit 20 to which the eyepiece optical units 13 a and 13 b are joined and the image emission unit 12 including the image display element 16 are configured as two divided parts. . The rod-shaped light guide 20 is coupled to and held by the armor 17 of the spectacle frame 11 via the rod-shaped light guide support 18, and with the spectacle frame 11 attached, the rod-shaped light guide as in the first embodiment. 20 is configured to extend horizontally within the viewer's right eye field of view. On the other hand, the image emitting unit 12 is held by the temple 14 of the spectacle frame 11. The image emitting unit 12 includes a display element 16 and is configured to emit image light toward the eyeball side surface at the rear end of the rod-shaped light guide unit 20 when the spectacle frame 11 is mounted.

  FIG. 14 is a horizontal sectional view schematically showing an optical system including the rod-shaped light guide unit 20. This rod-shaped light guide unit 20 is the rod-shaped light guide unit according to the first embodiment shown in FIG. 3, and the inner surface of the rear end inclined surface 22 of the rear end light guide member 25 is used as a mirror surface. The angle of inclination of the light portion 20 with respect to the longitudinal direction is made smaller, and an incident surface for allowing the first image light to be incident on the eyeball side of the rear end light guide member 25 is provided. The rear end inclined surface 22 constitutes a second reflecting surface.

  Further, instead of the display elements 16a and 16b of the first embodiment, one display element 16 having a width approximately twice that of the display elements is provided on the eyeball side of the rear end portion of the rod-shaped light guide unit 20. . The display element 16 is a liquid crystal element (LCD), and two light emitting diodes (LEDs) 43a and 43b for illumination are irradiated on the back surface of the display element 16 and the display element 16 is irradiated with white light from the LEDs 43a and 43b. Two illumination lenses 44a and 44b are provided as a backlight of the LCD. The display element 16 displays two screens corresponding to the first image light 51a and the second image light 51b side by side on the same LCD. Since other configurations are the same as those of the first embodiment, the same components are denoted by the same reference numerals, and description thereof is omitted.

  With the configuration as described above, according to the present embodiment, the first image light 51 a emitted from the display element 16 is incident from the eyeball side surface of the rear end light guide member 25 and reflected by the rear end inclined surface 22. Then, the light is incident on the boundary surface with the air gap 27 at an incident angle smaller than the critical angle, is transmitted therethrough, and enters the main light member 24. On the other hand, the second image light exits the display element 16 and enters the main light member 24 from the rear eyeball side side surface of the main light member 24. Since the optical path of the first image light 51a and the optical path of the second image light 51b after entering the main light guide member 24 are the same as those in the first embodiment, description thereof is omitted.

  As a result, in the head-mounted image display device 10 according to the present embodiment, as in the first embodiment, two horizontally arranged display images can be displayed in the observer's field of view. The display image can be a see-through image. Further, according to the present embodiment, the rear end inclined surface 22 of the rear end light guide member 25 is used as a mirror surface, and the first image light 51a and the second image light 51b are incident from substantially the same direction. As a result, the number of display elements 16 can be reduced to a simple device configuration. Further, since the rod-shaped light guide 20 and the image emitting unit 12 are separated and held separately by the armor 13 and the temple 14, respectively, the rod-shaped light guide 20 does not protrude even when the spectacle frame 11 is folded. Excellent portability, storage and aesthetics.

  In addition, this invention is not limited only to the said embodiment, Many deformation | transformation or a change is possible. For example, the head-mounted image display device may be configured by providing an image emitting unit, a rod-shaped light guide unit, an eyepiece optical unit, and the like on the left side or both eyes. Moreover, you may provide three or more eyepiece optical parts in one rod-shaped light guide part. In this case, three display images are horizontally arranged in the observer's field of view.

  Moreover, in each said embodiment, although the rod-shaped light guide part has faced the horizontal direction, it is not restricted to this. For example, an image emitting unit may be provided on the upper part of the spectacle frame, and the rod-shaped light guide unit may be extended and held in the field of view vertically downward therefrom. Or you may hold | maintain a rod-shaped light guide part to a spectacles frame so that it may extend in the diagonal direction.

  Further, although the display screen is displayed close to the left and right in FIG. 5, the present invention is not limited to this. It is also possible to further increase or decrease the interval between the two display images by adjusting the distance between the two eyepiece optical units. Further, the two images may be combined and displayed as a large screen so that the right end of the left image is in contact with the left end of the right image.

  Although the tip inclined surface in each embodiment and the rear end inclined surface in the ninth embodiment are mirror surfaces, mirrors are not formed on these end surfaces, and image light is incident on these end surfaces with a larger angle than the critical angle. It may be incident at an angle.

  Further, the head-mounted image display device according to the present invention is not limited to the glasses type, and can be configured as a headset type or as a glasses removable type.

DESCRIPTION OF SYMBOLS 10 Head-mounted image display apparatus 11 Eyeglass frame 12 Image emission part 13 Eyepiece optical part 13a First eyepiece optical part 13b Second eyepiece optical part 14 Temple 15 Eyeball 16 Display element 16a First display element 16b Second display element 17 Yoroi DESCRIPTION OF SYMBOLS 18 Bar-shaped light guide part support part 20 Bar-shaped light guide part 21 Front end inclined surface 22 Rear end inclined surface 23 Front end light guide member 24 Main light guide member 25 Rear end light guide member 26 Air gap 27 Air gap 28 Air gap 29 In half mirror 30 Side surface 31 Inner side surface 32 Rear end surface 33 Dichroic mirror 34 Polarization separation film 35 Polarization separation film 41, 41a, 41b Polarizer 42 Light modulation element 43a, 43b LED
44a, 44b Illuminating lens 50 Image 50a Left image 50b Right image 51a First image light 51b Second image light 52 Light from an object

Claims (14)

A plurality of eyepiece optical units that emit image light to be displayed toward the corresponding eyeballs;
A rod-shaped light guide unit that holds the plurality of eyepiece optical units and guides the image light to the corresponding eyepiece optical unit;
Holding the rod-shaped light guide unit, and having a head mounting part that can be detachably mounted on the observer's head,
In the state where the head mounting unit is mounted on the observer's head, an image of the image light from the plurality of eyepiece optical units is displayed within the visual field of the left or right eyeball of the observer. So as to hold the rod-shaped light guide ,
The rod-shaped light guide unit is disposed in order from the front end side in the light guide direction of each image light, and is disposed between the front light guide member and the main light member. Image light separating means for reflecting any one of the respective image lights and transmitting the other image light,
A head-mounted image display device characterized by that.   The head-mounted image display device according to claim 1, wherein the rod-shaped light guide unit has a width of a projection cross section in an observer's visual axis direction that is equal to or smaller than a pupil diameter.   The head-mounted image display device according to claim 1, wherein a part of an optical path of each of the image light overlaps in the rod-shaped light guide unit.   The rod-shaped light guide unit is configured such that any one of the respective image lights has an optical axis substantially parallel to a longitudinal direction of the rod-shaped light guide unit. The head-mounted image display device according to any one of the above.   The said rod-shaped light guide part was comprised so that any one of each said image light might be reflected in the inner surface extended in the longitudinal direction of the said rod-shaped light guide part. 5. The head-mounted image display device according to any one of 4 above. The head-mounted image display apparatus according to claim 1, wherein the image light separating unit is a half mirror. The image light separation means has an air gap, and any one of the respective image lights is incident on the image light separation means at an angle that is totally reflected by the image light separation means, and is reflected. image light head-mounted image display apparatus according to any one of claims 1 to 5, characterized in that to transmit is made incident on the image light separating means at an angle less than the angle that is the total reflection . Each of the image light, having different wavelengths from each other, the image light separating means according to any one of claims 1 to 5, characterized by having a dichroic mirror for separating the respective image light Head-mounted image display device. Each of the image light, having different polarization directions, the image light separating means, any one of the preceding claims, characterized in that it has a polarization separation film that separates the respective image light The head-mounted image display device described in 1. The rod-shaped light guide part has a first reflecting surface inclined with respect to the longitudinal direction at the light guide direction front end part,
Any one of the respective image lights reflected by the image light separating means is incident on any one of the plurality of eyepiece optical units, and any of the other image lights transmitted through the separating means one, the first is reflected by the reflecting surface, the other of the head-mounted image display device in any one of claims 1-9, characterized by being configured so as to be incident on the eyepiece optical unit. The rod-shaped light guide unit includes an image light coupling unit that reflects one of the image lights and transmits another image light to an incident part of the image light. The head-mounted image display device according to any one of 10 . The rod-shaped light guide has a second reflecting surface inclined at the rear end portion in the light guide direction with respect to the longitudinal direction of the rod-shaped light guide, and is incident from substantially the same direction as any one of the image lights. The head-mounted image display device according to claim 11 , wherein other image light is reflected by the reflection surface and is incident on the image light coupling unit. Further comprising an image emitting part for emitting the respective image light to the rod-shaped light guide part,
The head-mounted image display device according to any one of claims 1 to 12, wherein the image emitting unit is disposed outside a visual field of an observer. The head-mounted image display device according to claim 13, wherein the image ejection unit is held by a spectacle temple unit.

Images