JP3812053B2 - Synthetic optical system unit and projection display device using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a full-color projection display device using a plurality of reflective liquid crystal light valves, and in particular, to a light detection optical system emitted from a light valve of the device, and to color the detection light. The present invention relates to an analyzing optical system to be synthesized and a color synthesizing optical system.
[0002]
[Prior art]
The applicant of the present invention applied for a patent relating to a projection display device in Japanese Patent Application No. 8-288547. The configuration of the projection apparatus is shown in FIG. Light source light emitted from a light source (not shown) travels by changing the direction of the optical axis by a bending mirror 3, and reflects dichroic mirror 5 having characteristics of transmitting B light, transmitting G light and R light, and reflecting G light, R light, and B light. Dichroic mirrors 6 having transmission characteristics are made incident on cross dichroic mirrors arranged in an X shape. Of the two lights of the B light reflected by the cross dichroic mirror and the mixed light of the R light and the G light, the R light and the G light mixed light are bent at the optical axis by the bending mirror 7 to reflect the G light and the R light. The light is separated into G light that is incident upon and reflected by the dichroic mirror 9 having transmission characteristics and R light that is transmitted. The B light, G light, and R light color-separated by the color separation optical system having the above configuration are polarized beam splitters (PBS) 11B, 11G, 11 arranged for the respective color lights.RAnd undergoes a polarization separation action. Of the S-polarized light and the P-polarized light separated by the polarization separation unit of each PBS, only the reflected S-polarized light is incident on the reflective liquid crystal light valves 12B, 12G, and 12R arranged for each color light. Reflected and emitted light from the light valve including light modulated by the signal of each color light is again incident on the PBS, and only the modulated light is transmitted, that is, detected and emitted by the polarization separation unit of the PBS. Three colors are incident on the cross dichroic prism 13 constituting the color synthesizing optical system from different incident surfaces for each color, and are arranged in an X shape in the cross dichroic prism by the B light reflecting dichroic film 13B and the R light reflecting dichroic film 13R. The composition is achieved, the prism is emitted, and the projection lens 14 projects a full color image on the screen.
[0003]
Conventionally, when configuring such a projection display device, each component member is arranged in a box member that constitutes the appearance of the projection display device, and three colors are provided on the substrate that constitutes the floor member of the box member. A method of attaching and arranging components such as a resolving optical system, a light valve, PBS, and a dichroic prism has been adopted.
[0004]
[Problems to be solved by the invention]
However, when the above-mentioned components of the projection apparatus are arranged as described above, the so-called registration shift, in which the positions of the pixels for each color on the screen change due to changes in the environmental temperature during use of the projection apparatus. There was a big problem that occurred. In particular, in the case of a projection type display device that projects onto a large screen recently, the registration shift means deterioration of the projected image, which is a serious problem.
[0005]
An object of the present invention is to provide an arrangement of a light analyzing optical system and a color synthesizing optical system for obtaining a good image without registration deviation.
[0006]
[Means for Solving the Problems]
The present inventors have found that the registration deviation occurs because the floor member on which the light valve, the analyzing optical system and the color synthesizing optical system are fixedly arranged expands and contracts due to a change in environmental temperature. The position attached to the member changed, and as a result, it was thought that the pixels of each color would deviate from the initial alignment position.
[0007]
First, in order to reduce the expansion and contraction related to the temperature change of the floor member, a material having a small linear expansion coefficient may be selected as the floor member, but generally, the iron-based material that is representative of the material has a disadvantage that the weight is large. It is difficult to use. Furthermore, nickel alloys typified by Invar with a small temperature coefficient have excellent values as coefficients, but they are poor in workability and very expensive.
[0008]
The present inventors have come up with the present invention by thinking that the above problems can be solved while using a conventional aluminum alloy or a fiber-reinforced resin as a flooring material. In other words, in order to reduce the registration deviation, it is thought that it is only necessary to integrate an optical system through which the modulated light emitted from each light valve is synthesized and emitted, and further integrated. If the color synthesizing optical system arranged at the position closest to the projection lens among the members is fixed to the floor member, the defocusing of the projected image may be further reduced in combination with the effect of the integration. It was. This is because the projection lens is fixed to the floor member, and the distance between the projection lens and the combining optical system is small, and the change in the distance due to the temperature change can be ignored. According to a first aspect of the present invention, there is provided the first, second, and third liquid crystal light valves, the light source light that has been color-separated into first, second, and third color lights, and the liquid crystal light. A polarizing beam splitter for first, second, and third color light that analyzes light modulated from each of the bulbs, and a dichroic prism that combines the first, second, and third color lights and emits them as combined light. In the color synthesis optical system unit, the respective end faces of the first, second and third liquid crystal light valves and the respective one end faces of the respective color light polarization beam splitters are fixed and the respective color light polarization beam splitters. The other end face of each and the incident side end face of the dichroic prism on which each color light enters are fixed. According to a second aspect of the present invention, there is provided the first, second and third liquid crystal light valves, the light source light which is color-separated into the first, second and third color lights, and the liquid crystal light. A polarizing beam splitter for first, second, and third color light that analyzes light modulated from each of the bulbs, and a dichroic prism that combines the first, second, and third color lights and emits them as combined light. In the color synthesis optical system unit havingThe first, second and third liquid crystal light valves and the polarization beam splitter for each color light are fixed to each other, and the end surfaces of the respective liquid crystal light valves and one end surface of each of the color light polarization beam splitters are fixed relative to each other. The polarization beam splitter for each color light and the dichroic prism on which each color light is incident are fixed to the other end surface of each polarization beam splitter for each color light and the incident side end surface of the dichroic prism. It was set as the characteristic characterized by doing.
[0009]
According to a third aspect of the present invention, there is provided the first, second, and third liquid crystal light valves, the light source light that has been color-separated into the first, second, and third color lights, and the liquid crystal light. A polarizing beam splitter for first, second, and third color light that analyzes light modulated from each of the bulbs, and a dichroic prism that combines the first, second, and third color lights and emits them as combined light. In the color synthesis optical system unit havingThe first, second and third liquid crystal light valves and the polarization beam splitter for each color light are respectively fixed, and the polarization beam splitter for each color light and the dichroic prism on which each color light is incident are fixed. . According to a fourth aspect of the present invention, the dichroic prism includes three triangular prisms or two triangular prisms and a square prism.First of the present invention5In the first aspect and the second aspect, the first aspect and the second aspect are configured such that one end surface of the polarization beam splitter for R color light, G color light, and B color light and one end surface of the dichroic prism are integrally held by an attachment member. It was set as the structure to do. First of the present invention6In the first aspect and the second aspect, the first aspect and the second aspect are configured such that one end surface of the polarization beam splitter for R color light, G color light, and B color light is bonded to one end surface of the dichroic prism via a transparent member. It was set as the structure hold | maintained integrally.
[0010]
First of the present invention7In the aspect of any one of the first to fourth aspects, the mounting member or the bottom surface of the dichroic prism is the installation surface of the color composition unit, and the liquid crystal light valve and the polarization beam splitter for each color light are , And away from the installation surface. First of the present invention8The color separation optical system for separating light source light into R color, G color, and B color light, and each color light that separates each of R, G, and B color light color-separated from the color separation optical system. A polarizing beam splitter, a reflective liquid crystal light valve for R, G, and B color light that modulates each color light polarized and separated by each of the polarized light beam splitters for colored light, and a reflective liquid crystal for each of R, G, and B colored light A color synthesis dichroic prism that synthesizes each color light modulated from a light valve and guides it to a projection lens; and the R, G, B color light polarization beam splitter, and the R, G, B color light reflective liquid crystal The light valve and the color composition dichroic prism are the first mode.To any of the seventh aspectsIt is composed of a synthesis optical system unit.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described in detail below.
(First Embodiment of the Present Invention) FIG. 1 shows light valves 112R, 112G, 112B, polarization beam splitters (PBS) 11R, 11G, 11B, and a combining optical system according to the first embodiment of the present invention. 5 is a configuration perspective view showing an integrated cross dichroic prism 13. For convenience of explanation, coordinate axes X, Y, and Z orthogonal to each other are defined as shown in the figure. In addition, the figure7The same part numbers are used for the same constituent members as those in the projection device shown.
[0012]
In FIG. 1, a holding member 31 is a member having a function of holding and integrating the three-color composition cross dichroic prism 13 and the polarization beam splitters (PBS) 11R, 11G, and 11B for each color.
FIG. 2 shows the structure of the holding member 31. The holding member 31 basically has a rectangular parallelepiped shape, and the holding member 31 has a space for accommodating a dichroic prism for color synthesis. Further, the upper portion (Z direction) has an opening 32 provided with an entrance function for accommodating the color composition dichroic in the space. That is, the dichroic prism is disposed inside through the opening from the −Z direction, and is bonded and fixed.
[0013]
Further, the holding member has a structure having openings 33R, 33B, 33G, and 34 in the Y direction, -Y direction, X direction, and -X direction, respectively, and these openings penetrate into the space for the dichroic prism. It has become. Among these openings, the openings in the X direction, the Y direction, and the −Y direction serve to guide the modulated light from the reflective liquid crystal light valve that has passed through the polarization beam splitter (PBS) for each color light to the cross dichroic prism for color synthesis. To do. Further, the members 35R, 35B, 35G constituting the three openings 33R, 33B, 33G themselves are pawls for positioning the PBS so that the arrangement is not shifted in the −Y direction, the −X direction, and the Y direction. To play the role. The holding member main body 31 is provided with holding members 36R, 36B, and 36G protruding from each opening in the Y direction, the −Y direction, and the X direction so that each PBS can be arranged and fixed at the position. The distal end portion is inserted, and the holding member 31 and the PBS are bonded, fixed, and integrated.
[0014]
1, the dichroic prism 13 is inserted, bonded, and fixed to the holding member 31 with a predetermined fit in the internal space as shown in the figure.
In the present embodiment, fixing and holding is achieved with an adhesive between the four corner ridge lines of the dichroic prism and the portion of the holding member 31 facing the member.
The holding member 31 is formed by aluminum die casting, and is further subjected to surface blackening treatment such as black alumite treatment in order to ensure a predetermined shape and prevent scattering of incident light. The integration of each color PBS and liquid crystal light valve will be described with reference to FIG.
[0015]
In order to achieve the object of the present invention, first, as described above, the dichroic prism, the PBS for each color, and the liquid crystal light valve are integrated, and they are integrated after the registration of the light valve for each color light. It is necessary to Each component necessary for registration of the light valve will be described.
[0016]
First, the first attachment members 22R, 22G, and 22B will be described.
The first attachment members 22R, 22B, and 22G are members produced by press-forming an iron plate material (SPC material), and the entire surface is subjected to solder plating. The shape has an opening that is slightly larger than the image forming portion of the light valve in the substantially central portion, and on the side thereof, there are four soldered parts with regard to second mounting members 21R, 21B, 21G and member 22R described later. The foot portions 22R-1, 22R-2, 22R-3, and 22R-4 are formed so as to protrude in the X direction and the −X direction, respectively. Further, the upper portion in the Z direction of the member 22R has portions 22R-5 and 22R-6 bent in the −Y direction with a predetermined width, and the R light PBS is placed in the upper and lower bent portions. The first attachment member 22R and the PBS 11R are attached in such a structure that the opening is sandwiched between the R light incident surfaces in a configuration facing the opening. The PBS 11R and the bent portions 22R-5 and 22R-6 are fixed with an adhesive.
[0017]
The attachment members 22G and 22B have the same structure and are attached and fixed to the PBSs 11B and 11G.
In FIG. 3, the PBSs 11R, 11B, and 11G are illustrated as already attached to the fixing member 31, but the PBSs 11R, 11B, and 11G are first attached to the fixing member 31 and then the PBSs 11R, 11B are attached. The first attachment members 22R, 22B, and 22G may be attached to the 11G by the above-described method, and the attachment members 22R, 22B, and 22G may be attached to the PBS 11R, 11B, and 11G in the above-described manner before the PBSs 11R and 11B. 11G may be attached to the holding member 31.
[0018]
Next, the second attachment members 21R, 21B, and 21G will be described.
As shown in the second mounting member 21R for B light (the overall shape is easy to understand 21B), the members 21R, 21B, and 21G are stamped with the same SPC material as the first mounting members 22R, 22B, and 22R. The entire surface is solder plated. The shape is the same as the first mounting member in that it has an opening in the approximate center and the feet 21R-1, 21R-2, 21R-3, and 21R-4 on both sides. It is a plane and does not have a bent part. Another difference from the first attachment member is that the liquid crystal light valves 112R, 112B, and 112G for each color light are attached to the second attachment member, so that three screw portions are formed so as to be attached.
[0019]
The second mounting members 21R, 21B, and 21G and the liquid crystal light valves 112R, 112B, and 112G need to be screwed and fixed with screws using the screw portions in advance.
Next, the liquid crystal light valves 112R, 112B, and 112G used in this embodiment will be briefly described.
[0020]
The liquid crystal light valves 112R, 112B, and 112G are respectively composed of liquid crystal light valve main body portions 12R, 12B, and 12G and holding members made of a resin that protects the liquid crystal light valve main body portions 12R, 12B, and 12G. The resin member is protected except for the omitted wiring portion. When viewed from the rear, the light valve sees the resin protection part as shown by 12R and 112G in FIG. 3, and when viewed from the front, the light valve main body 12B is incident through the opening as shown by 112B. An exit surface is desired. The light valve 112R, 112B, 112G has a hole for attaching the light valve 112R, 112B, 112G and the second mounting member 21R, 21B, 21G with screws on the incident side of the light valve 112R, 112B, 112G.
[0021]
The light valve main bodies 12R, 12B, and 12G used in the present embodiment belong to the reflection type liquid crystal light valve among the light valves as described above, and are further referred to as electric writing type reflection type liquid crystal light valves. It is.
The structure of the main body is composed of a glass substrate, a transparent electrode (ITO), a liquid crystal modulation layer, a metal electrode constituting a pixel, a nonlinear switching element such as a TFT, and a Si substrate from the incident surface. A voltage is applied between the metal electrode and the transparent electrode by switching of the TFT, and the liquid crystal molecules in the liquid crystal layer are arranged to function as a modulation layer. That is, the linearly polarized light incident on the switched part is emitted as linearly polarized light whose polarization direction is changed by 90 degrees, and the polarized light at the other part is emitted as the same polarized light as the incident polarized light. .
[0022]
A procedure for integrating the dichroic prism, each color PBS and the liquid crystal light valve using the above-described components will be described.
The holding of the PBSs 11R, 11B, and 11G for each color to the holding member 31 is achieved by inserting the PBSs 11R, 11G, and 11B into the PBS holding portion of the holding member 31 and fixing them with an adhesive.
Further, the light valves 112R, 112B, and 112G are screwed and fixed to the second mounting members 21R, 21B, and 21G with screws through the holes from the back side. Next, the integrated body of the second mounting member and the light valve is fixed to the first mounting member mounted on the PBSs 11R, 11B, and 11G to achieve complete integration.
At the time of this integration, the liquid crystal light valve must also be registered. The method will be described.
[0023]
The integration of the first mounting member and the second mounting member is performed by locally heating the solder on the relative body surfaces of the opposing feet of the two members as described above. Achieved by:
The feet of both members are soldered in advance as described above, but before carrying out this work, solder is applied to one or both of the first mounting member and the second mounting member. It is easier to do the soldering work if it is prepared.
[0024]
To heat locally, the first mounting member and the second mounting member are temporarily fixed to each other by temporarily fixing the feet, and the laser is irradiated to the feet, the solder is melted by the irradiation, This is achieved by wetting and cooling with the solder plated in advance.
This work is carried out between both the left and right foot portions of the first holding member and the second holding member, but the foot portions protrude from the left and right sides, so that they are separated from the light valve and the PBS. Soldering is possible at a location, and the influence of temperature rise due to soldering can be minimized.
[0025]
Since the liquid crystal light valve body itself cannot be said to have good temperature resistance, soldering by this structure is very effective.
The important point in this work is that the registration for each color on the light valve main bodies 12R, 12B, and 12G and the conjugate property of each light valve with respect to the projection lens are achieved (the focus position is each light valve). The same). For this purpose, for example, first, the foot portion of the second attachment member to which the light valve 112G is attached and the first attachment member 22G are attached as described above. Of course, it is needless to say that a projection lens needs to be attached and projected at that time.
[0026]
Next, the first attachment member 22R and the second attachment member 21R are attached by soldering. At this time, the position of soldering and the thickness of solder so that the G light pixel and the R light pixel are aligned at the same position so that the registration is consistent over the entire surface. Adjust while adjusting.
Further, the first attachment member 22B and the second attachment member 21B are attached by soldering so that the registration of the R light and G light pixels coincides.
[0027]
By doing so, registration of the light valves 112R, 112B, and 112G and conjugation with the projection lens can be achieved.
In addition, although this operation | work may be the operation | work after attaching the projection lens of a projection apparatus, a jig | tool for exclusive use is produced and the integration shown in FIG. 1 of this Embodiment is comprised, You may assemble what achieved the said integration as a projection apparatus.
[0028]
In the integrated structure shown in FIG. 1 of the present embodiment, it is important that only the holding member 31 is attached to the floor portion of the projection main body, and this may be achieved by bonding, or the lower four corners of the holding member 31. Alternatively, the screw portion may be configured in advance and attached to the floor portion using the screw portion.
FIG. 7 is an overall explanatory view of a projection display device incorporating the combining optical system unit of the present embodiment. Since the liquid crystal light valve in the conventional projector is a floor member that is not symmetrical about the optical axis, it shifts in the direction perpendicular to the optical axis due to temperature changes, so the registration process in the subsequent process is difficult. there were. However, by using the integrated structure shown in this embodiment as a composite optical system of the projection display device, the relative position between the liquid crystal light valves can be adjusted between the PBS and the dichroic prism even if the environmental temperature changes. Since the glass member and the metal constituting the holding member 31 have an axisymmetric structure with respect to the optical axis, the liquid crystal light valve shifts in the optical axis direction but does not shift in the direction perpendicular to the optical axis. The amount of deviation can be greatly reduced compared to the above, and the subsequent registration adjustment work can be simplified.
[0029]
In consideration of the environmental resistance of the projection type display device, a glass material having a small photoelastic constant as the glass material of each of the three PBSs of the color synthesis optical system unit of the present invention described above (the value of the photoelastic constant is 1.5 × 10 8 cm 2 / N or less), since the occurrence of birefringence caused by environmental temperature changes or stress generated during mounting is small, unevenness in illuminance does not occur, the contrast of the projected image is improved, and a good projected image is obtained. It is very effective to get.
(Second embodiment of the present invention)
FIG. 4 is a structural perspective view showing a second embodiment of the present invention. In FIG. 4, the same component numbers are used for the same components as those used in the previous embodiment.
[0030]
In the previous embodiment, the color composition dichroic prism 13 and the polarization beam splitter (PBS) are coupled using the holding member 31, but this embodiment does not use the holding member. .
In the present embodiment, the color composition cross dichroic prism 13 and the polarization beam splitters 11R, 11B, and 11G are integrated by adhering and fixing the optical glass members 41R, 41B, and 41G with an adhesive. Shall be achieved.
[0031]
In the present embodiment, as in the previous embodiment, the polarized light splitter (PBS) 11R receives R light separated in three colors in the −X direction.InThe R light that is incident and reflected by the polarization separation unit of the PBS 11R exits the PBS 11R in the Y direction, and is incident on the R light reflective light valve 112R disposed immediately on the exit surface. G light by three-color separation to PBS11G-Y directionInThe polarized light that is incident, reflected and emitted by the polarization separation unit of the PBS is incident on the light valve 112 for G light.
[0032]
Similarly, the three-color-separated B light is incident on the PBS 11B in the −X direction, and is incident on the light valve 112B by the polarization separation unit of the PBS.
The light including the modulated light emitted from the light valves for each color light is again incident on the PBS for each light, and only the modulated light of each color light is transmitted through the polarization separation section of the PBS to achieve the detection, and the members 41R, 41G , 41B and incident on the color composition cross dichroic prism 13, and the color composition light is emitted in the −X direction as projection light.
[0033]
By using the members 41R, 41G, and 41B in this way, the respective color light PBSs 11R, 11G, and 11B and the cross dichroic prism 13 can be integrated, and at the same time, they can be arranged at predetermined positions based on the optical design. It becomes possible. Furthermore, if the members 41R, 41B, and 41G are not used, each color light PBS and the cross dichroic prism are bonded and arranged. However, if the optical design is the same, each member needs to be enlarged. This will cause an increase in cost.
[0034]
In the present embodiment, since each member has only to be set to a minimum size, no waste occurs.
The optical members 41R, 41G, and 41B may be transparent glass members, and the refractive index may be the same as or different from the refractive indexes of the PBSs 11R, 11G, and 11B or the cross dichroic prism 13. .
[0035]
The light valves 112R, 112G, 112B for each color light and the PBSs 11R, 11G, 11B for each color light use the same mounting members 21R and 22R, 21G and 22G, 21B and 22B as described in the previous embodiment, The registration of each color light and the conjugateness of each color light valve to the projection lens can be ensured.
[0036]
In the present embodiment, the integrated assembly method including the light valve, the PBS, and the cross dichroic prism is placed at a predetermined position, and the dichroic prism 13 and the members 41R, 41G, 41B are pasted, and further PBS11R, 11G, 11B. The first attachment members 22R, 22G, and 22B may be fixed to the injection surface of the PBS 11R, 1G, and 11B after the member is pasted, or the members 22R, 22G, and 22B are fixed and attached to the PBS 11R, 11G, and 11B in advance. The members 41R, 41G, and 41B may be sandwiched and fixed to the cross dichroic prism.
[0037]
As in the previous embodiment, the light valves 112R, 112G, and 112B are screwed to the second mounting members 21R, 22G, and 22B with screws, and then the foot portions of the members are opposed to the first mounting member. Integration is completed by performing soldering while achieving the same focal point adjustment and pixel registration of each light valve.
[0038]
Similar to the previous embodiment, by attaching only the lower surface of the integrated cross dichroic prism according to the embodiment of the present embodiment to the floor member substrate of the projection apparatus by a method such as adhesion, registration due to a change in environmental temperature and The occurrence of defocus can be minimized.
(Third embodiment of the present invention)
FIG. 5 shows a perspective configuration diagram showing the third embodiment.
[0039]
In the previous embodiment, the cross dichroic prism 13, the PBSs 11R, 11G, and 11B and the light valves 112R, 112G, and 112B are joined using the joining members 41R, 41G, and 41B and the attachment members 21R, 22R, 21G, 22G, 21B, and 22B. At the mounting position of the PBS and the light valve, the R light, G light and B light separated by the three-color separation optical system of the projection device shown in FIG. In this configuration, the S-polarized light reflected by the polarized light separating portion of the polarized light separated by the light portion is incident on the light valve.
[0040]
In this embodiment, of the light incident on the PBS, the P-polarized light transmitted through and emitted from the PBS's polarization splitting unit is incident on the light valve for each color.
That is, the R light is incident on the PBS 11R in the −X direction, and the P-polarized light that is transmitted through and exits the polarization separation portion of the PBS 11R is incident on the light valve 112R (not shown because it is disposed behind the PBS). . The light modulated and reflected by the light valve member 12R in the light valve is incident again on the PBS 11R in the X direction, and only the modulated light is reflected (analyzed) by the polarization separating unit of the PBS 11R by the polarization separating unit. , Passes through the member 41R and enters the cross dichroic prism 13.
[0041]
Similarly, the B light is also incident on the PBS 11B, and the P-polarized light that has been transmitted through the polarization splitting unit is incident on the light valve member 12B (not shown because it is disposed behind the PBS 11B), modulated and reflected, and only the modulated light is detected. The light is incident on the cross dichroic prism 13 through the member 41B.
The G light incident on the PBS 11G from the Y direction passes through the polarization separation section of the PBS 11G, is modulated and reflected by the light valve member 12G in the light valve 112G, enters the PBS 11G again, and is reflected by the polarization separation section of the PBS 11G. Only the modulated light is reflected and analyzed, and enters the cross dichroic prism 13 in the −X direction through the member 41G.
[0042]
Each photo-analyzing light incident on the cross dichroic prism 13 is combined in three colors by the R light reflecting dichroic film 13R and the B light reflecting dichroic film 13B arranged in the X shape in the dichroic prism, and is projected and synthesized in the −X direction. Injected as light.
In the present embodiment, since the light valves 112R, 112G, 112B for the respective color lights are arranged at the positions shown in FIG. 5, the first mounting members 21R, 21G, 21B and the second mounting members 22R, 22G, 22B The foot part of each member is joined by soldering, but the foot part has a structure that projects to the left and right sides of the mounting member, so it is placed on the cross dichroic prism side of the projecting foot part. Thus, the members 41R, 41G, and 41B have an effect of configuring a space that allows the members to be arranged.
[0043]
Further, in the present embodiment, the light valves 112R,112GThe first mounting members 22R, 22G, and 22B for mounting 112B and the second members 21R, 21G, and 21B have their feet for soldering protruding in the ± X and ± Y directions. It is also possible to adopt a configuration in which all of these are protruded in the ± Z direction. In the case of this structure, the protruding portion for sandwiching and fixing the PBSs 11R, 11G, and 11B of the first attachment members 22R, 22G, and 22B is configured between the feet. This configuration is effective when the thickness of the members 41R, 41G, and 41B is small.
[0044]
In the present embodiment, the modulated light emitted from each color light valve is configured such that the light reflected by the polarization separation section of the PBS for each color is synthesized by the cross dichroic prism and emitted as projection light. In addition, the light emitted from each color light valve employed in the first and second embodiments is transmitted through the PBS and incident on the cross dichroic prism, and the PBS for each color is attached as compared with the configuration in which the three colors are combined. Placement accuracy is required.
[0045]
This is because if there is a rotation of the PBS around the Z axis in the figure, in this embodiment, the deviation of the optical axis is twice that of the first and second embodiments.
(Fourth embodiment of the present invention)
The fourth embodiment shows another combining optical system that does not use a cross dichroic prism as a combining optical system, for example, using a dichroic prism having a dichroic film arranged on a predetermined surface of three triangular prisms. This is a case where a color synthesis optical system is configured.
[0046]
FIG. 6 is a structural perspective view showing an embodiment of the present invention in which the dichroic prism 113 is used. In addition, the same part number is used about the same structural member as before. Further, although coordinate axes X, Y, and Z shown in the figure are orthogonal to each other, as described later, in the present embodiment, since the optical axis of B light is not parallel to the X coordinate in each color light, this light is used. A new axis X ′ is defined which is parallel to the XY plane and not parallel to the X axis.
[0047]
The dichroic prism used in the present embodiment is configured such that the triangular prisms 113-1, 113-2, and 113-3 are configured with the B light reflecting dichroic film 113B and the G light reflecting dichroic film 113G at the illustrated positions, respectively. This is a color combining prism in which a prism member is bonded with an adhesive.
As in the previous embodiment, the optical members 41R, 41G, and 41B have the same structure as that of the previous embodiment in which the PBSs 11R, 11G, and 11B are bonded to the combined light incident surfaces of the combined dichroic prism 113.
[0048]
In the present embodiment, R light, G light, and B light travel in the Z direction in the three-color separation optical system and enter the respective color light PBSs 11R, 11G, and 11B. In order to obtain this configuration, the dichroic prism shown in the present synthesis optical system is prepared for color separation instead of the three-color separation optical system shown in FIG. 7, and is arranged immediately below the dichroic prism 113 (−Z direction). The light source light is incident in the Y direction to separate the three colors, the R light is emitted in the Y direction, the G light is emitted in the −X direction, and the B light is emitted in the X ′ direction. Each color light can be achieved by arranging a bending mirror for each color, changing the optical axis in the Z direction for each color, and entering each color light PBS 11R, 11G, 11B.
[0049]
Because of the above configuration, the directions of the polarization separation units of the PBSs 11R, 11G, and 11B are the directions shown in the drawing.
The positions where the light valves 112R, 112G, 112B for the respective colors are arranged are arranged so that the P-polarized light of each color light that has passed through the polarization separation unit of each color light incident on each PBS 11R, 11G, 11B enters the light valve. ing.
[0050]
The light valves 112R, 112G, and 112B are attached to the PBSs 11R, 11G, and 11B in the same manner using the first attachment members 22R, 22G, and 22B and the second attachment members 21R, 21G, and 21B.
In the present embodiment, the bent portions for attaching the first attachment members 22R, 22G, and 22B to the PBSs 11R, 11G, and 1B are configured between the soldering feet of the members.
[0051]
The emitted light modulated by the light valve main body in each color light valve 112R, 112G, 112B is incident on the PBSs 11R, 11G, 11B again, and only the modulated light is reflected by the polarization separator and passes through the optical members 41R, 41G, 41B. The light is incident on the dichroic prism 113 integrated with each other from each color incident surface.
[0052]
The R light detection light incident on the prism member 113-3 of the dichroic prism 113 in the −Y direction travels straight and is emitted from the dichroic prism 113 in the −Y direction. G light analysis light is prism member113The light enters the −2 in the X direction, is reflected by the dichroic film 113G2, travels in the −Y direction, and exits the dichroic prism 113 in the −Y direction. The B light incident on the prism 113-1 in the −X ′ direction undergoes total reflection once to change the traveling direction, is reflected by the dichroic film 11B, travels in the −Y direction, and is emitted in the same direction. As described above, the dichroic prism 113 achieves the three-color synthesis and emits it, and the projection lens projects it.
[0053]
Needless to say, only the dichroic prism 113 needs to be fixed to the floor member in the present embodiment.
Furthermore, a so-called Philips type dichroic prism using two triangular prisms and a square prism is known as a composite optical system using a dichroic prism having a shape close to a dichroic prism using three triangular prisms. In the case of the prism, three prisms cannot be bonded as shown in the present embodiment. because. This is because it is necessary to use total reflection by forming a gap between the prisms. In this case, it is necessary to achieve integration using a holding member as described in the first embodiment.
[0054]
As described above, even in a combining optical system using three triangular prisms, represented by the Philips type color combining dichroic prism, the prism, each color light PBS, and each color light valve are integrated into one embodiment of the present invention. Thus, the effects of the present invention can be similarly achieved.
As a further form, in the above embodiment, the first mounting member and the second mounting member are soldered to achieve integration of each color PBS and the light valve, but the mounting member is not used. Needless to say, the light valve can be directly attached to the PBS. In that case, it attaches with an adhesive agent, performing registration adjustment as mentioned above.
[0055]
In this case, it goes without saying that the same effect can be obtained.
[0056]
【The invention's effect】
As described above in the embodiment of the present invention, by integrating the light valve, the PBS, and the color composition dichroic prism, the shift of the corresponding pixel for each color due to the change in the environmental temperature is achieved. In addition to minimization, it is possible to provide a projection display device that has the effect of minimizing defocus.
[Brief description of the drawings]
FIG. 1 is a structural perspective view showing a first embodiment of the present invention.
FIG. 2 is a structural perspective view of members used to integrate a cross dichroic prism and PBS in the first embodiment.
FIG. 3 is a perspective view showing a state in which the light valve and the PBS according to the first embodiment are joined.
FIG. 4 is a structural perspective view showing a second embodiment of the present invention.
FIG. 5 is a structural perspective view showing a third embodiment of the present invention.
FIG. 6 is a structural perspective view showing a fourth embodiment of the present invention.
FIG. 7 is a diagram illustrating an entire projection display device.
[Explanation of symbols]
11R, 11B, 11G Polarizing beam splitter
12R, 12B, 12G Light valve member
13 Cross dichroic prism
21R, 21B, 21G First mounting member
22R, 22B, 22G Second mounting member
112R, 112B, 112G Light valve
113 Color synthesis optical system unit using triangular prism

Claims (8)

The first, second, and third liquid crystal light valves and the light source light that has been color-separated into the first, second, and third color lights are polarized and separated, and the light modulated from each of the liquid crystal light valves is modulated. In a color combining optical system unit having first, second and third color light polarizing beam splitters for analyzing light, and a dichroic prism which combines the first, second and third color lights and emits them as combined light.
Each end face of each of the first, second and third liquid crystal light valves and one end face of each color light polarization beam splitter are fixed, and the other end face of each color light polarization beam splitter and each color. A color synthesizing optical system unit characterized in that an incident side end face of the dichroic prism on which light is incident is fixed. The first, second, and third liquid crystal light valves and the light source light that has been color-separated into the first, second, and third color lights are polarized and separated, and the light modulated from each of the liquid crystal light valves is modulated. First, second and third polarizing beam splitters for color light to be analyzed, and first, second and second
A color synthesizing optical system unit having a dichroic prism that synthesizes the three color lights and emits them as synthesized light;
The first, second and third liquid crystal light valves and the polarization beam splitter for each color light are fixed to each other, and the end surfaces of the respective liquid crystal light valves and one end surface of each of the color light polarization beam splitters are fixed relative to each other. The polarization beam splitter for each color light and the dichroic prism on which each color light is incident, and the other end surface of each polarization beam splitter for each color light and the incident side end surface of the dichroic prism are fixed relative to each other. A color synthesizing optical system unit. The first, second, and third liquid crystal light valves and the light source light that has been color-separated into first, second, and third color lights are polarized and separated, and the light modulated from each of the liquid crystal light valves First, second and third polarizing beam splitters for color light to be analyzed, and first, second and second
A color synthesizing optical system unit having a dichroic prism that synthesizes the three color lights and emits them as synthesized light;
The first, second and third liquid crystal light valves and the polarization beam splitter for each color light are respectively fixed, and the polarization beam splitter for each color light and the dichroic prism on which each color light is incident are fixed. Color synthesis optical system unit. The color synthesis optical system unit according to any one of claims 1 to 3, wherein the dichroic prism includes three triangular prisms or two triangular prisms and a square prism. Any for R color light, from claim 1, characterized in that integrally held by one end surface and the mounting member to each end surface and the dichroic prism of the polarization beam splitter for the respective color light for G color light for and B color light according to claim 4 color combining optical system unit according to any one of claims. For R color light, through the transparent member and the end surface of one end surface and the dichroic prism of the polarization beam splitter for the respective color light for G color light for and B color light, according to claim claim 1, characterized in that integrally held by adhesion 5. The color synthesis optical system unit according to any one of 4 above. The mounting member or the bottom of the dichroic prism becomes the installation surface of the unit for color synthesis, liquid crystal light valve and a polarization beam splitter for the respective color lights, claim from claim 1, characterized in that apart from the installation surface 6 The color synthesis optical system unit described in any one of the above. A color separation optical system that separates light source light into R, G, and B color light, and a polarization beam splitter for each color light that separates each of R, G, and B color light that has been color-separated from the color separation optical system. The R, G, B color light reflecting liquid crystal light valves for modulating the respective color lights polarized and separated by the respective color light polarizing beam splitters, and the R, G, B color light reflecting liquid crystal light valves, respectively. A dichroic prism for color synthesis that synthesizes each of the colored lights and guides them to a projection lens, the polarizing beam splitter for R, G, B color light, and the reflective liquid crystal light valve for R, G, B color light, A projection type display device comprising a color composition optical system unit according to any one of claims 1 to 7, wherein the color composition dichroic prism.

Images