JP2012155119A - Projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a projector capable of suppressing a decrease in use efficiency of illumination light and suppressing heat generation of a light shielding device when a high quality image is obtained using a light shielding device capable of adjusting a light shielding state for improving contrast. To provide.
When adjusting a light shielding state by a light control mechanism 31 for improving contrast, a double lens array that is a uniform optical system from a light source device 21 in an illumination optical system 20 according to the change in the light shielding state. The condenser lens 22, which is an optical component arranged up to 24 and 25 and the superimposing lens 27, is moved along the direction of the light beam optical axis by the lens driving device 81 a, so that the light beam passing through the light control mechanism 31 is moved. The state is being adjusted. Thereby, the fall of the utilization efficiency of the illumination light inject | emitted from the illumination optical system 20 can be suppressed, and it can suppress that the light modulation mechanism 31 heat | fever-generates.
[Selection] Figure 1

Description

  The present invention relates to a projector including a light blocking unit for adjusting the state of illumination light.

  In projectors, for example, by incorporating a variable aperture in the illumination system, the amount of light shielded by the variable aperture can be increased or decreased according to the presence or absence of external light to achieve both brightness and contrast, and to suppress deterioration of the variable aperture. (See Patent Document 1). In addition, it is known that a pair of light-shielding members that can be opened and closed by rotation are arranged symmetrically with respect to the illumination optical axis between a pair of lens arrays in the illumination device, and the amount of illumination light is adjusted. (For example, refer to Patent Document 2). In addition, an optical element is also known that can be inserted into and removed from the optical path (see, for example, Patent Document 3).

  However, in any of the above, since a part of the light flux from the light source is shielded by the light shielding portion, the amount of light that can be effectively used is reduced and the image becomes dark. Further, the light shielding part may generate heat with the shielded light.

JP 2004-361856 A JP 2004-264819 A JP 2007-78815 A

  The present invention has been made in view of the above-described problems of the background art, and in the case of using a light shielding device capable of adjusting the light shielding state for improving contrast or the like, the light use efficiency is increased and the light shielding device generates heat. An object is to provide a projector capable of suppressing this.

  In order to solve the above problems, a projector according to the present invention includes (a1) a light source, (a2) a light-shielding device capable of adjusting a light-shielding state of light from the light source, and (a3) uniformizing light from the light source. An optical system, (a) an illumination optical system having (a4), (b) a light modulation device illuminated by an illumination light beam from the illumination optical system, and (c) projecting light modulated through the light modulation device A projection optical system, wherein (d) the illumination optical system includes at least one component arranged from the light source to the homogenization optical system, with a light beam optical axis corresponding to a change in the light shielding state. A drive device that moves along the direction of the light beam, and by changing the arrangement of the at least one component, the state of the light beam incident on the light shielding device can be adjusted.

  In the projector, when the light shielding state is adjusted by the light shielding device, the state of the light beam incident on the light shielding device is changed by changing the arrangement of the at least one optical component according to the change in the light shielding state. It is adjusting. Thereby, for example, when the light shielding state is adjusted by the light shielding device to improve the contrast, the diameter or density of the light beam incident on the light shielding device can be changed according to the change in the light shielding state. It is possible to suppress a decrease in utilization efficiency and to prevent the light shielding device from generating heat.

  According to a specific aspect of the present invention, the component whose arrangement is changed by the driving device is a condenser lens for collimating light from the light source, and the driving device attaches the condenser lens to the light beam optical axis. Move along the direction. In this case, by moving the condenser lens, the diameter of the light beam incident on the light shielding device can be changed according to the state of the light shielding device, so that highly efficient light can be used.

  According to another aspect of the present invention, the driving device moves the light source along the direction of the light beam optical axis. In this case, by moving the light source, the diameter of the light beam incident on the light shielding device can be changed according to the state of the light shielding device, so that highly efficient use of light can be achieved.

  According to still another aspect of the present invention, the light blocking device includes a plate-shaped light blocking portion that can advance and retreat on the optical path. In this case, by changing the arrangement relationship of the constituent members in accordance with the arrangement of the light shielding portions, it is possible to form a light beam in a desired state while suppressing waste of light from the light source light.

  According to still another aspect of the present invention, the light blocking device includes a pair of light blocking portions that partially block light from the light source and adjust the light blocking state by an opening / closing operation that rotates in synchronization. In this case, by changing the arrangement relationship of the constituent members according to the opening / closing operation of the pair of light shielding portions, it is possible to form a light flux in a desired state while suppressing waste of light from the light source light.

  According to still another aspect of the present invention, the illumination optical system includes a cylindrical lens that converges the light beam corresponding to the opening / closing direction of the pair of light shielding portions. In this case, by adjusting the positional relationship between the cylindrical lens and the light source, the diameter of the light beam incident on the light-shielding device can be changed with respect to a specific direction, so that highly efficient light can be used.

  According to still another aspect of the present invention, the pair of light-shielding portions changes in the open / closed state according to the average value of the brightness of light modulated by the light modulation device, and the illumination optical system according to the average value. The arrangement relationship of the constituent members is changed. In this case, a bright and high-contrast image can be formed by associating the degree of opening / closing of the pair of light shielding portions with the degree of modulation in the light modulation device.

1 is a plan view conceptually showing a projector according to a first embodiment. (A), (B) is a figure for demonstrating an example of operation | movement of the illumination optical system of the projector shown in FIG. (A), (B) is a figure for demonstrating the relationship between the state of a light-shielding part, and the state of an illumination light beam. It is a top view which shows notionally the projector which concerns on 2nd Embodiment. (A), (B) is a figure for demonstrating another example of operation | movement of the illumination optical system of the projector shown in FIG. It is a top view which shows notionally the projector which concerns on 3rd Embodiment. It is a top view which shows notionally the projector which concerns on 4th Embodiment. It is a side view for demonstrating operation | movement of the illumination optical system of the projector shown in FIG. (A), (B) is a figure which shows notionally an illumination optical system among the projectors which concern on 5th Embodiment. (A), (B) is a figure for demonstrating an example of operation | movement of the illumination optical system of the projector shown in FIG. (A), (B) is a figure for demonstrating another example of operation | movement of the illumination optical system of the projector shown in FIG.

[First Embodiment]
The projector according to the first embodiment of the present invention will be described below with reference to FIG. The illustrated projector 100 includes an optical system portion 10 for image formation and projection, and a control device 90 that controls the operation of the optical system portion 10.

[1. Projector optics)
The optical system portion 10 shown in FIG. 1 includes an illumination optical system 20 that emits illumination light, a color separation light guide optical system 40 that separates illumination light from the illumination optical system 20 into three color lights of blue, green, and red, and a color A light modulating unit 50 that modulates the three color lights emitted from the separation light guide optical system 40 according to image information, a light combining optical system 60 that combines the image light of each color emitted from the light modulating unit 50, and light combining A projection optical system that projects the image light combined by the optical system 60 onto a screen (not shown). Among these, the optical parts from the illumination optical system 20 to the light combining optical system 60 are housed inside the optical component casing 11.

  The illumination optical system 20 includes, as optical components, a light source device 21, a condenser lens 22, first and second lens arrays 24 and 25, a polarization conversion device 26, a superimposing lens 27, and a light control mechanism. 31. Furthermore, the illumination optical system 20 includes a lens driving device 81a and a light shielding unit driving mechanism 83a as mechanical structural components.

  The light source device 21 is a light source that emits a light beam for illumination. For example, a discharge-type arc tube 21a such as a high-pressure mercury lamp, and an elliptical surface that collects the light beam emitted from the arc tube 21a and returns it to the front. And a reflector 21b which is a concave mirror of the mold. The condenser lens 22 is a concave lens that serves to collimate the light beam from the light source device 21. The first and second lens arrays 24 and 25 are fly-eye lenses each composed of a plurality of element lenses arranged in a matrix. Among these, the light beam emitted from the light source device 21 is divided into a plurality of partial light beams by the element lenses constituting the first lens array 24. In addition, each partial light beam from the first lens array 24 is emitted at an appropriate divergence angle by the element lenses constituting the second lens array 25. The polarization conversion device 26 is composed of a prism array incorporating a PBS and a wavelength plate, and is a polarization conversion unit that converts the split light beam emitted from the lens array 25 into only linearly polarized light in a specific direction and supplies it to the next stage optical system. is there. The superimposing lens 27 appropriately superimposes the illumination light as linearly polarized light that has passed through the polarization converter 26 as a whole, thereby superimposing illumination on the liquid crystal light valves 50r, 50g, and 50b of the respective colors provided in the illuminated region, that is, the light modulation unit 50. Enable. In other words, the illumination light that has passed through both the lens arrays 24 and 25 and the superimposing lens 27 passes through the color separation light guide optical system 40 described in detail below, and each color liquid crystal panel 51r, provided in the light modulation unit 50. 51g and 51b are uniformly superimposed and illuminated. In other words, the lens arrays 24 and 25 and the superimposing lens 27 function as a uniformizing optical system.

  The lens driving device 81 a is a driving mechanism for moving the condenser lens 22. More specifically, the lens driving device 81a has a motor and a guide (not shown), and moves the attachment portion 81b to which the condenser lens 22 is attached in the direction along the light beam optical axis SA, that is, the X direction. As a result, as indicated by an arrow A1 in the figure, the condenser lens 22 can reciprocate along the light beam optical axis SA. As described above, the lens driving device 81a moves the condenser lens 22 which is one of the optical components constituting the illumination optical system 20 along the light beam optical axis SA, so that the light source device in the illumination optical system 20 is obtained. The relative arrangement relationship between the lens 21 and the condenser lens 22 can be changed.

  The light control mechanism 31 is disposed inside the illumination optical system 20, for example, between the first and second lens arrays 24 and 25, and is a single plate-shaped light shielding portion 33 that extends across the light beam optical axis SA. Have The light shielding part 33 moves in the Y direction by being connected to a light shielding part drive mechanism 83a having a motor or the like (not shown). The cross-sectional shape and emission intensity of the illumination light emitted from the illumination optical system 20 are adjusted by making the light shielding portion 33 advanceable and retreatable on the optical path. As shown in FIG. 3B, the light-shielding portion 33 has a rectangular opening OP in the central portion of the rectangle, and in the on state, the light shielding portion 33 is on the center side corresponding to the portion of the opening OP. Only the light beam component is allowed to pass and the other light beam components are shielded. The light shielding portion 33 is made of, for example, a metal plate having a relatively high heat resistance.

  The color separation light guide optical system 40 includes first and second dichroic mirrors 41a and 41b, reflection mirrors 42a, 42b, and 42c, and three field lenses 43r, 43g, and 43b, and is emitted from the light source device 21. The separated illumination light is separated into three colors of red (R), green (G), and blue (B), and the separated color lights are guided to the liquid crystal light valves 50r, 50g, and 50b at the subsequent stage. More specifically, first, the first dichroic mirror 41a reflects the R illumination light LR out of the three RGB colors and transmits the G and B illumination lights LG and LB. Further, the second dichroic mirror 41b reflects the G illumination light LG of the two colors GB and transmits the B illumination light LB. That is, the red light LR reflected by the first dichroic mirror 41a is guided to the first optical path OP1 with the field lens 43r, is transmitted through the first dichroic mirror 41a, and is reflected by the second dichroic mirror 41b. The green light LG is guided to the second optical path OP2 having the field lens 43g, and the blue light LB having passed through the second dichroic mirror 41b is guided to the third optical path OP3 having the field lens 43b. The field lenses 43r, 43g, and 43b for the respective colors are adjusted so that the partial light beams emitted from the second lens array 25 have an appropriate incident angle on the irradiated areas of the liquid crystal light valves 50r, 50g, and 50b. is doing. The pair of relay lenses 44a and 44b is disposed on a third optical path OP3 that is relatively longer than the first optical path OP1 and the second optical path OP2, and an image formed immediately before the first relay lens 44a on the incident side. By transmitting the light to the field lens 43b on the exit side almost as it is, the light use efficiency is prevented from being lowered due to light diffusion or the like.

  The light modulation unit 50 includes three liquid crystal light valves 50r, 50g, and 50b into which illumination lights LR, LG, and LB of three colors are incident, respectively. Each of the liquid crystal light valves 50r, 50g, and 50b is a non-light-emitting light modulator that modulates the spatial distribution of the intensity of incident illumination light.

  Each of the liquid crystal light valves 50r, 50g, 50b includes a liquid crystal panel 51r, 51g, 51b disposed in the center, and an incident side polarizing filter 52r, 52g, 52b disposed on one light incident side so as to sandwich the liquid crystal panel 51r, 51g, 51b. Emission side polarization filters 53r, 53g, and 53b are provided on the other light emission side, respectively. The liquid crystal panels 51r, 51g, and 51b are not shown in the drawings, but a light-transmitting substrate having a transparent electrode or the like, a light-transmitting driving substrate having a pixel electrode or the like, and between the light-transmitting substrate and the driving substrate And a liquid crystal layer hermetically sealed. The color lights LR, LG, LB incident on the liquid crystal light valves 50r, 50g, 50b are in units of pixels in accordance with the drive signals or image signals input as electrical signals to the liquid crystal light valves 50r, 50g, 50b. Intensity modulated.

  The light combining optical system 60 is a cross dichroic prism, has a substantially square shape in plan view in which four right angle prisms are bonded together, and a pair of dichroic mirrors 61 intersecting in an X shape at the interface where the right angle prisms are bonded together. , 62 are formed. Both dichroic mirrors 61 and 62 are formed of dielectric multilayer films having different characteristics. That is, one first dichroic mirror 61 reflects red light LR, and the other first dichroic mirror 62 reflects blue light LB. The light combining optical system 60 reflects the modulated red light LR from the liquid crystal light valve 50r by the first dichroic mirror 61 and emits it in the Z direction by bending the optical path, and modulates green light from the liquid crystal light valve 50g. The light LG is transmitted through the first and second dichroic mirrors 61 and 62 so as to travel straight in the Z direction, and the modulated blue light LB from the liquid crystal light valve 50b is reflected by the second dichroic mirror 62 to bend the optical path. To inject in the Z direction. On the light emitting side of the light combining optical system 60, the color lights LR, LG, and LB are superimposed to perform color combining.

  The projection optical system 70 is a projection lens that enlarges and projects the color image light combined by the light combining optical system 60. The projection lens 71 is a zoom lens that projects images on the liquid crystal panels 51r, 51g, 51b onto a screen (not shown) at a desired magnification. The projection optical system 70 projects a color moving image or a color still image obtained by synthesizing each color image corresponding to the drive signal or display signal input to each liquid crystal panel 51r, 51g, 51b on the screen at a desired magnification.

[2. Projector control system)
As shown in FIG. 1, the control device 90 drives the liquid crystal light valves 50 r, 50 g, and 50 b based on the image processing unit 91 to which an external image signal such as a video signal is input and the output of the image processing unit 91. A panel drive unit 92, a light control mechanism drive unit 93 that operates the light control mechanism 31 based on the output of the image processing unit 91, and an optical element drive that drives the lens drive device 81a according to the operating state of the light control mechanism 31. Unit 94 and a main control unit 99 that controls the operation of the circuit portions 91 and 94 and the like in an integrated manner.

  In the control device 90, the image processing unit 91 can perform various types of image processing including color correction and distortion correction on the input external image signal, and an image corresponding to the external image signal can be added as an additional function. Instead of or in a superimposed manner, character information or the like can be displayed.

  The panel drive unit 92 generates a drive signal for adjusting the state of each of the liquid crystal light valves 50r, 50g, and 50b based on the image signal after image processing output from the image processing unit 91. Accordingly, an image as a transmittance distribution can be formed in the liquid crystal light valves 50r, 50g, and 50b corresponding to the image signal input from the image processing unit 91.

  The dimming mechanism driving unit 93 controls the open / closed state of the dimming mechanism 31. That is, the dimming mechanism drive unit 93 causes the dimming mechanism 31 to perform an operation of switching between an on state in which the light shielding unit 33 is disposed on the optical path and an off state in which the light shielding unit 33 is retracted outside the optical path.

  The optical element driving unit 94 controls the lens driving device 81a in conjunction with the control state of the dimming mechanism 31 by the dimming mechanism driving unit 93, that is, the light shielding state. That is, the optical element driving unit 94 adjusts the distance from the light source device 21 to the condenser lens 22 in the X direction along the light beam optical axis SA by displacing the condenser lens 22 along the light beam optical axis SA.

  The main control unit 99 includes a microcomputer, a memory, and the like, and operates based on a program appropriately prepared for controlling the image processing unit 91, the optical element driving unit 94, and the like. Thereby, the operation state of the projector 100 is appropriately maintained.

[3. Dimming operation of illumination optical system)
Hereinafter, an example of the light control operation in the illumination optical system 20 will be described with reference to FIGS. 2 (A) and 2 (B). Here, as described above, the lens driving device 81a operates, and the condenser lens 22 is movable in the X direction. That is, the distance from the light source device 21 to the condenser lens 22 changes as the condenser lens 22 moves in the direction of the arrow A1.

  First, as shown in FIG. 2A, a case where the light shielding unit 33 is in an off state retracted from the optical path is set as a reference first state. In this case, the condenser lens 22 is disposed at a first position Q1 that is a distance X1 with respect to the position P0 where the light source device 21 is disposed. On the other hand, as shown in FIG. 2B, the second state is a case where the light-shielding portion 33 is in an on state where it is disposed on the optical path. In this case, the condenser lens 22 has moved away from the light source device 21 by a distance D. That is, it is shifted from the reference first state by the distance D to the optical path downstream side (+ X side). As a result, the condenser lens 22 is disposed at the second position Q2, which is a distance X2 (X2> X1) with respect to the position P0. In the second state, the distance from the light source device 21 to the condenser lens 22 is increased by the distance D compared to the first state. Thereby, the cross section of the light beam when entering the light shielding portion 33 from the condenser lens 22 is reduced. That is, when the optical part of the illumination optical system 20 changes from the first state to the second state, the beam diameter of the illumination light incident on the light shielding unit 33 becomes relatively thin.

  Hereinafter, the light beam cross section of the illumination light in the first state and the second state will be specifically described with reference to FIGS. 3 (A) and 3 (B).

  First, as shown in FIG. 3A, in the case of the off state in which the light shielding unit 33 is retracted, that is, in the first state of FIG. The entire area including the outer peripheral portion that may be blocked by the effective area EF of the illumination system. Accordingly, by operating the lens driving device 81a and disposing the condenser lens 22 at the position Q1 so as to cover such a wide effective area EF, the light beam cross section LF1 when the light beam enters the light shielding portion 33 is relatively large. It becomes a state.

  On the other hand, as shown in FIG. 3B, in the case of the on state in which the light shielding portion 33 is arranged, that is, in the second state of FIG. That is, a portion corresponding to the opening OP that is a portion remaining without being blocked by the light blocking portion 33 is an effective area EF ′ of the illumination system. Therefore, by operating the lens driving device 81a and disposing the condenser lens 22 at the position Q2 so as to cover such a narrow effective area EF ′ without waste, the light beam cross-section LF2 when the light beam is incident on the light shielding portion 33 is obtained. It becomes a relatively small state. In this case, since the effective area EF ′ is only the range of the central portion that is narrower than the effective area EF in FIG. 3A, for example, image formation giving priority to high contrast is possible.

  In the above description, by moving the condenser lens 22 by the distance D in the X direction according to the open / closed state of the light control mechanism 31, the diameter, density, etc. of the light flux are adjusted in accordance with the first and second states. ing. Thereby, the light from the light source device 21 can be used with high efficiency, the light shielded by the light shielding unit 33 can be reduced, and the heat generated by the light shielding is also suppressed.

  As described above, in the projector 100 according to the present embodiment, when the light control mechanism 31 adjusts the light shielding state to improve the contrast, the light source device 21 in the illumination optical system 20 responds to the change in the light shielding state. By moving the condenser lens 22, which is an optical component disposed between the lens arrays 24, 25, which are a uniformizing optical system, and the superimposing lens 27, along the direction of the light beam optical axis by the lens driving device 81 a, The state of the light beam incident on the light control mechanism 31 is adjusted. Thereby, the fall of the utilization efficiency of the illumination light inject | emitted from the illumination optical system 20 can be suppressed, and it can suppress that the light modulation mechanism 31 heat | fever-generates.

[Second Embodiment]
Hereinafter, the configuration of the optical system of the projector according to the second embodiment will be described. The projector according to the second embodiment is a modification of the projector 100 according to the first embodiment, and portions that are not particularly described are the same as those in the first embodiment.

  FIG. 4 corresponds to FIG. 1, and the projector 200 shown includes an optical system part 210 for image formation and projection, and a control device 90 that controls the operation of the optical system part 210. Of the optical system portion 210, an illumination optical system 220 that is partially different from that of the first embodiment includes a light source driving device 82a as a mechanical component. That is, the difference is that a light source driving device 82a is provided instead of the lens driving device 81a of FIG.

  The light source driving device 82 a is a driving mechanism for moving the light source device 21. More specifically, the light source driving device 82a has a motor and a guide (not shown), and an attachment portion 82b to which the arc tube 21a and the reflector 21b are integrally attached is arranged in the direction along the light beam optical axis SA, that is, in the X direction. Move. As a result, as indicated by an arrow A2 in the figure, the light source device 21 can reciprocate along the light beam optical axis SA. As described above, the light source driving device 82a moves the light source device 21 which is one of the optical components constituting the illumination optical system 20 along the light beam optical axis SA, so that the light source device in the illumination optical system 20 is obtained. The relative arrangement relationship between the lens 21 and the condenser lens 22 can be changed.

  Hereinafter, an example of the light control operation in the illumination optical system 220 will be described with reference to FIGS. 5 (A) and 5 (B).

  Here, as described above, the light source driving device 82a operates and the light source device 21 is movable in the X direction. That is, the distance from the light source device 21 to the condenser lens 22 changes as the light source device 21 moves in the direction of the arrow A2. Specifically, in the first state as a reference shown in FIG. 5A, the light source device 21 disposed at the first position P1, which is a distance X1 with respect to the position Q0 where the condenser lens 22 is disposed. However, in the second state shown in FIG. 5B, the distance D is moved away from the condenser lens 22. That is, it is shifted from the reference first state by the distance D to the optical path upstream side (−X side). As a result, the light source device 21 is disposed at the second position P2 that is the distance X2 (X2> X1) with respect to the position Q0. Thereby, the cross section of the light beam when entering the light shielding portion 33 from the condenser lens 22 is reduced. That is, when the optical part of the illumination optical system 220 changes from the first state to the second state, the beam diameter becomes relatively thin.

  As described above, also in the projector 200 of the present embodiment, when the light control state is adjusted by the light control mechanism 31 to improve the contrast, the light source device 21 in the illumination optical system 220 is changed according to the change in the light shield state. Is moved along the direction of the optical axis of the light beam, thereby adjusting the state of the light beam incident on the light control mechanism 31. Thereby, the fall of the utilization efficiency of the illumination light inject | emitted from the illumination optical system 220 can be suppressed, and it can suppress that the light modulation mechanism 31 heat | fever-generates.

[Third Embodiment]
Hereinafter, the configuration of the optical system of the projector according to the third embodiment will be described. Note that the projector according to the third embodiment is a modification of the projector 100 according to the first embodiment, and parts that are not particularly described are the same as those according to the first embodiment.

  FIG. 6 corresponds to FIG. 1 and FIG. 4, and the projector 300 shown includes an optical system part 310 for image formation and projection, and a control device 90 that controls the operation of the optical system part 310. . Of the optical system portion 310, an illumination optical system 320 that is partially different from the first embodiment includes a lens driving device 81a and a light source driving device 82a as mechanical structural components.

  That is, the projector 300 includes both the lens driving device 81a of the first embodiment and the light source driving device 82a of the second embodiment. By operating the lens driving device 81a and the light source driving device 82a, respectively, both the condenser lens 22 and the light source device 21 can be moved, and the distance from the light source device 21 to the condenser lens 22 and the distance from the condenser lens 22 to the lens array 24. Can be changed.

  As described above, also in the projector 300 of the present embodiment, when the light control state is adjusted by the light control mechanism 31 to improve the contrast, the light source device 21 of the illumination optical system 320 is changed according to the change of the light shield state. The condenser lens 22 is moved along the direction of the optical axis of the light beam, thereby adjusting the state of the light beam incident on the light control mechanism 31. Thereby, the fall of the utilization efficiency of the illumination light inject | emitted from the illumination optical system 320 can be suppressed, and it can suppress that the light modulation mechanism 31 heat | fever-generates.

[Fourth Embodiment]
The configuration of the optical system of the projector according to the fourth embodiment will be described below. Note that the projector according to the fourth embodiment is a modification of the projector 300 according to the third embodiment, and parts that are not particularly described are the same as those according to the third embodiment.

  FIG. 7 corresponds to FIG. 6 and the like, and the illustrated projector 400 includes an optical system portion 410 for image formation and projection, and a control device 90 that controls the operation of the optical system portion 410. Of the optical system portion 410, the illumination optical system 420 includes a light control mechanism 431 as an optical component. That is, the third embodiment is different from the third embodiment in that a dimming mechanism 431 operated by the light shielding unit driving mechanism 483a is provided instead of the dimming mechanism 31 operated by the light shielding unit driving mechanism 83a of FIG. For convenience of explanation, the projector 400 includes both the light source driving device 82a and the lens driving device 81a. However, the projector 400 may include only one of them and omit the other.

  The light control mechanism 431 is disposed inside the illumination optical system 420, for example, between the first and second lens arrays 24 and 25, and exits from the illumination optical system 420 by opening and closing the pair of light shielding portions 433 and 434. At least a part of the illumination light is continuously or stepwise blocked to adjust the illumination state, that is, the aperture angle of the illumination light. FIG. 8 is a side view for explaining the operation of the illumination optical system 420. As shown in the figure, the pair of light shielding portions 433 and 434 are arranged symmetrically with respect to the light beam optical axis SA, and adjust the opening shape by rotating synchronously.

  In the case of the present embodiment as well, the arrangement relationship is adjusted by reciprocating the light source device 21 and the condenser lens 22 in the directions indicated by the arrows A1 and A2 in accordance with the change in the opening shape due to the operation of the light control mechanism 431. ing. Thereby, it is possible to suppress a decrease in utilization efficiency of the illumination light emitted from the illumination optical system 420 and to suppress the light control mechanism 431 from generating heat. Further, in this case, the light control mechanism 431 enables continuous or stepwise light shielding, and according to this, the movement amount of the light source device 21 or the condenser lens 22 is changed continuously or stepwise. You can also. Further, for example, the open / closed state of the pair of light shielding units 433 and 434 and the distance from the light source device 21 to the condenser lens 22 may be changed according to the average value of the brightness of the light modulated by the light modulation unit 50. . That is, the degree of opening / closing of the light shielding units 433 and 434 and the degree of adjustment by the driving devices 82a and 81a may be associated with the degree of modulation in the light modulation unit 50. Accordingly, the projector 400 can form a bright and high-contrast image as necessary.

[Fifth Embodiment]
The configuration of the optical system of the projector according to the fifth embodiment will be described below. Note that the projector according to the fifth embodiment is a modification of the projector 400 according to the fourth embodiment, and parts other than a part of the illumination optical system are the same as in the case of the fourth embodiment. The illustration and description are omitted for.

  FIGS. 9A and 9B are diagrams illustrating the structure of a projector 500 according to the fifth embodiment. As illustrated, the illumination optical system 520 of the projector 500 according to the present embodiment includes a condenser lens group 522 as an optical component. That is, the difference is that a condenser lens group 522 is provided instead of the condenser lens 22 of FIGS.

  The condenser lens group 522 includes first and second cylindrical lenses 522a and 522b that have a refractive power only in one direction on the lens surface and no refractive power in the other direction. As shown in the figure, the first cylindrical lens 522a located on the upstream side of the optical path does not change the convergence of the light beam in the Y direction, which is the direction corresponding to the opening / closing direction of the pair of light shielding portions 433 and 434, and in the Z direction. Only collimate the luminous flux. In contrast, the second cylindrical lens 522b positioned on the downstream side of the optical path collimates the light beam in the Y direction corresponding to the opening / closing direction of the pair of light shielding portions 433 and 434, and converges the light beam in the Z direction. Do not change the degree. In this case, the dimming mechanism is obtained by changing the distance between the light source device 21 and the second cylindrical lens 522b having power corresponding to the opening / closing direction of the pair of light shielding portions 433 and 434 with respect to convergence from the light source device 21. Adjustment of the luminous flux corresponding to the change in the aperture shape of 431 becomes possible. In addition, about the 1st cylindrical lens 522a, it becomes possible to ensure the width | variety of the light beam about a Z direction by maintaining the distance XX with the light source device 21. FIG.

  Hereinafter, an example of the light control operation in the illumination optical system 520 will be described with reference to FIGS. 10 (A) and 10 (B).

  Here, it is assumed that the second cylindrical lens 522b is movable in the X direction, and the light source device 21 and the first cylindrical lens 522a are at fixed positions P0 and R0, respectively. That is, in this case, the distance from the light source device 21 to the second cylindrical lens 522b is changed by the movement of the second cylindrical lens 522b in the direction of the arrow A1.

  First, as shown in FIG. 10A, a case where the pair of light-shielding portions 433 and 434 are completely open is set as a reference first state, and in this case, the second cylindrical lens 522b is used as the light source device. It is assumed that it is arranged at a first position Q1 that is a distance X1 with respect to a position P0 at which 21 is arranged. On the other hand, as shown in FIG. 10B, the case where the pair of light shielding portions 433 and 434 are in a state of being closed to some extent is referred to as the second state. In this case, the second cylindrical lens 522b is Only E moves away from the light source device 21. That is, it is shifted from the reference first state by the distance E toward the optical path downstream side (+ X side). As a result, the condenser lens 22 is disposed at the second position Q2, which is a distance X2 (X2> X1) with respect to the position P0. Thereby, the cross section of the light beam when entering the light shielding portions 433 and 434 from the condenser lens 22 becomes small. That is, when the optical part of the illumination optical system 420 changes from the first state to the second state, the beam diameter becomes relatively thin.

  Hereinafter, another example of the light control operation in the illumination optical system 520 will be described with reference to FIGS. 11 (A) and 11 (B).

  Here, it is assumed that the light source device 21 and the first cylindrical lens 522a are movable in the X direction, and the second cylindrical lens 522b is in a fixed position Q0. That is, in this case, the distance from the light source device 21 to the second cylindrical lens 522b changes as the light source device 21 moves in the direction of the arrow A2. Note that the first cylindrical lens 522a moves in the direction of the arrow A2 in synchronization with the light source device 21.

  First, as shown in FIG. 11A, a case where the pair of light-shielding portions 433 and 434 are completely open is set as a reference first state, and in this case, the light source device 21 includes the second cylindrical lens. It is arranged at a first position P1 which is a distance X1 with respect to a position Q0 at which 522b is arranged. On the other hand, as shown in FIG. 11B, the case where the pair of light-shielding portions 433 and 434 are in a state of being closed to some extent is referred to as a second state. 2 is moved away from the cylindrical lens 522b. That is, it is shifted from the reference first state by the distance E to the optical path upstream side (−X side). As a result, the light source device 21 is disposed at the second position P2 that is the distance X2 (X2> X1) with respect to the position Q0. Thereby, the cross section of the light beam when entering the light shielding portions 433 and 434 from the second cylindrical lens 522b becomes small. That is, when the optical part of the illumination optical system 520 changes from the first state to the second state, the beam diameter becomes relatively thin. As the light source device 21 moves, the first cylindrical lens 522a also moves from the first position R1 to the second position R2, so that the distance XX from the first cylindrical lens 522a to the light source device 21 is constant. To be kept.

  Also in the case of this embodiment, the arrangement relationship is adjusted by moving the light source device 21 and the second cylindrical lens 522b in accordance with the change in the opening shape caused by the operation of the light control mechanism 431. Thereby, the fall of the utilization efficiency of the illumination light inject | emitted from the illumination optical system 220 can be suppressed, and it can suppress that the light modulation mechanism 431 heat | fever-generates.

  In addition, this invention is not restricted to said embodiment, In the range which does not deviate from the summary, it can be implemented in a various aspect, For example, the following deformation | transformation is also possible.

  First, in the above embodiment, the light source device 21 and the condenser lens 22 are moved as an example of at least one optical component disposed from the light source device 21 to the uniformizing optical system such as the lens arrays 24 and 25. However, as long as the state of the light beam incident on the light shielding device can be adjusted, other optical components may be moved. Moreover, it is good also as an aspect of moving only one component of the light source devices 21, for example like the arc tube 21a.

  For the dimming mechanism 431 having the pair of light shielding portions 433 and 434 of the fourth and fifth embodiments, for example, in the description of the operation in the fifth embodiment, the fully opened first is shown. Although the operation is shown only in two stages of the first state and the second state that is closed to some extent, the degree of opening and closing of the pair of light shielding portions 433 and 434 can be made in multiple stages. In this case, the movement distance of the light source device 21 and the like is also set in multiple stages to be linked with the light shielding state. For example, when the pair of light shielding parts 433 and 434 is opened and closed in n stages (n> 2), the movement distance of the light source device 21 and the like may be changed in n stages. The distance may be changed in m steps (m <n) smaller than the open / closed state.

  Further, the structure having the condenser lens group 522 of the fifth embodiment can be applied to the structure including the light control mechanism 31 like the projector 100 of the first embodiment.

  Further, the condenser lens group 522 of the fifth embodiment is not limited to a combination of cylindrical lenses, and various modes such as a combination of a toric lens and a cylindrical lens and a combination of toric lenses are possible. .

  In the above embodiment, a high-pressure mercury lamp is used as the arc tube 21a of the light source device 21 provided in the illumination optical system 20 or the like, but various light sources such as a metal halide lamp can be used as the arc tube 21a.

  In the above embodiment, the polarization conversion device 26 that converts the light from the light source device 21 or the like into polarized light in a specific direction is used. However, the present invention is also applicable to a projector that does not use such a polarization conversion device 26. .

  In the above embodiment, an example in which the present invention is applied to a projector including transmissive liquid crystal light valves 50r, 50g, and 50b has been described. However, the present invention is also applied to a projector including a reflective liquid crystal light valve. It is possible. Here, “transmission type” means that a liquid crystal light valve including a liquid crystal panel transmits light, and “reflection type” means that the liquid crystal light valve reflects light. It means that there is.

  As a projector, there are a front projection type projector that projects an image from the direction of observing the projection surface, and a rear projection type projector that projects an image from the side opposite to the direction of observing the projection surface. The configurations of the projectors 100 and 200 shown in FIG.

  In the above embodiment, only the examples of the projectors 100 and 200 using the three liquid crystal light valves 50r, 50g, and 50b have been described. However, the present invention may include four or more projectors using one or two liquid crystal light valves. It can also be applied to projectors using liquid crystal light valves. When a projector is configured with a single liquid crystal light valve, this liquid crystal light valve serves as a display unit.

  In the projectors 100 and 200 according to the above-described embodiments, the light modulation of each color is performed using the color separation light guide optical system 40, the liquid crystal light valves 50r, 50g, 50b, and the like. Color light modulation and synthesis by using a combination of an illuminated color wheel and a device (light valve as a light modulator) that is composed of pixels of a micromirror and is irradiated with light transmitted through the color wheel Can also be done.

  As a projector, there is an apparatus (OHP) of a type that illuminates a sheet-like original and enlarges and projects an enlarged image of the original with a projection lens, but the present invention is also applicable to this type of projector. At this time, the document support table serves as the display unit, and the detection unit detects information such as the temperature of the connecting unit interposed between the support table and the projection lens.

  DESCRIPTION OF SYMBOLS 10 ... Optical system part, 11 ... Optical component housing, 20 ... Illumination optical system, 21 ... Light source device, 22 ... Concave lens, 24, 25 ... Lens array, 26 ... Polarization conversion device, 27 ... Superimposing lens, 31 ... Tone Optical mechanism, 81a ... Lens drive device, 82a ... Light source drive device, 83a, 483a ... Light-shielding portion drive mechanism, 81b, 82b ... Mounting portion, 40 ... Color separation light guide optical system, 41a, 41b ... Dichroic mirror, 42a, 42b , 42c ... reflective mirror, 43r, 43g, 43b ... field lens, 50 ... light modulator, 50r, 50g, 50b ... liquid crystal light valve, 51r, 51g, 51b ... liquid crystal panel, 52r, 52g, 52b ... incident side polarization filter 53r, 53g, 53b... Emission side polarizing filter, 60... Photosynthesis optical system, 61 and 62. Croic mirror, 70 ... projection optical system, 71 ... projection lens, 90 ... control device, 91 ... image processing unit, 92 ... panel drive unit, 93 ... light control mechanism drive unit, 94 ... optical element drive unit, 95 ... lens Drive control unit, 99 ... main control unit, 100, 200 ... projector, LB ... blue light, LG ... green light, LR ... red light, OA ... optical axis, OP1, OP2, OP3 ... optical path

Claims (7)

An illumination optical system comprising: a light source; a light shielding device capable of adjusting a light shielding state of the light from the light source; and a homogenizing optical system for uniformizing the light from the light source.
A light modulation device illuminated by an illumination light beam from the illumination optical system;
A projection optical system for projecting light modulated through the light modulation device;
A projector comprising:
The illumination optical system has a drive device that moves at least one component member arranged from the light source to the homogenization optical system along the direction of a light beam optical axis in response to a change in a light shielding state, A projector characterized in that the state of a light beam incident on the light shielding device can be adjusted by changing the arrangement of the at least one constituent member. The structural member whose arrangement is changed by the driving device is a condenser lens for collimating light from the light source,
The projector according to claim 1.   The projector according to claim 1, wherein the structural member whose arrangement is changed by the driving device is the light source.   The projector according to any one of claims 1 to 3, wherein the light shielding device includes a plate-shaped light shielding portion that can advance and retreat on an optical path.   The said light-shielding apparatus has a pair of light-shielding part which shields the light from the said light source partially by the opening / closing operation | movement which rotates synchronously, and adjusts a light-shielding state. The projector according to item.   The projector according to claim 5, wherein the illumination optical system includes a cylindrical lens that converges a light beam corresponding to an opening / closing direction of the pair of light shielding portions.   The pair of light-shielding portions has an open / close state that varies according to an average value of brightness of light modulated by the light modulation device, and an arrangement of the at least one component is changed according to the average value. The projector as described in any one of Claim 5 and Claim 6.

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