WO2018029987A1 - Wavelength-selective retardation element and projection display device - Google Patents

Wavelength-selective retardation element and projection display device Download PDF

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Publication number
WO2018029987A1
WO2018029987A1 PCT/JP2017/022460 JP2017022460W WO2018029987A1 WO 2018029987 A1 WO2018029987 A1 WO 2018029987A1 JP 2017022460 W JP2017022460 W JP 2017022460W WO 2018029987 A1 WO2018029987 A1 WO 2018029987A1
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Prior art keywords
light
wavelength
phase difference
selective phase
difference element
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PCT/JP2017/022460
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French (fr)
Japanese (ja)
Inventor
圭祐 本間
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ソニー株式会社
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Priority to JP2018532855A priority Critical patent/JPWO2018029987A1/en
Publication of WO2018029987A1 publication Critical patent/WO2018029987A1/en

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    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/30—Polarising elements
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/14—Details

Definitions

  • one piece of a wavelength selective phase difference element is formed.
  • the thickness of the birefringent material for example, a quartz plate
  • the thickness crossing for maintaining the performance is about ⁇ 1 ⁇ m, the manufacturing yield is lowered. Therefore, development of a wavelength-selective phase difference element that is easy to handle and has high performance is desired.
  • a first wavelength selective phase difference element includes a light incident surface and a light output surface, and a first member, a second member, and a second member, which are sequentially bonded between the light incident surface and the light output surface.
  • the thickness ratio of the first member, the second member, and the third member is 2: 2: 3 from the light incident surface side or the light emitting surface side.
  • a first projection display device includes one or a plurality of light source units that emit light having a plurality of different wavelength bands, and light having a predetermined wavelength component among the light emitted from the light source unit.
  • Selection element that transmits or reflects light, a plurality of light modulation elements that respectively modulate light in a plurality of wavelength bands, a color composition element that combines light in each wavelength band emitted from the plurality of modulation elements, and color composition
  • the second member and the third member have a relationship of a ratio of 2: 2: 3 from the light incident surface side or the light emitting surface side, and at least one member is composed of two plate-like members. I did it.
  • each value in the ratio of 2: 2: 3 in the first member, the second member, and the third member corresponds to the thickness in the case where each of the first member, the second member, and the third member is composed of one plate-like member, and the two plates This is equivalent to the thickness difference in the case of the shape member.
  • the first and second wavelength selective phase difference elements of the embodiment of the present disclosure and the first and second projection display devices of the embodiment the first bonded in this order from the light incident surface side. Since the member, the second member, and the third member have a ratio of 2: 2: 3 from the light incident surface side or the light output surface side, it is possible to design the film thickness of each member to be thick. Therefore, handling of each member becomes easy. Further, since the number of constituent members is reduced as compared with a general wavelength selective phase difference element, it is possible to improve surface accuracy and parallelism. Therefore, it is possible to provide a wavelength-selective phase difference element that is easy to handle and has high performance.
  • FIG. 6 is a characteristic diagram illustrating a relationship between a wavelength of a wavelength selective phase difference element and a polarization conversion rate in Comparative Example 2.
  • FIG. It is a characteristic view showing the relationship between the wavelength of a wavelength selective phase difference element in comparative example 3, and a polarization conversion rate.
  • FIG. 1 is a perspective view of a configuration of a wavelength selective phase difference element (wavelength selective phase difference element 10) according to the first embodiment of the present disclosure.
  • the wavelength selective phase difference element 10 is used in, for example, a projection type display device (for example, the projector 1 (FIG. 11)) described later, and has such a characteristic that the polarization direction rotates only in a selective wavelength band. It is a phase difference plate.
  • the wavelength-selective phase difference element 10 of the present embodiment has a light incident surface S1 and a light exit surface S2, and the first member 11, the second member 12, and the third member 13 are arranged from the light incident surface S1 side. It has the structure bonded in this order.
  • the wavelength-selective phase difference element 10 of the present embodiment has a characteristic that the polarization direction rotates in a selective wavelength band (for example, a red band, a green band, or a blue band). .
  • the first member 11, the second member 12, and the third member 13 are plate-like members having a predetermined thickness, and are made of a phase difference material, for example, a uniaxial crystal or a uniaxial organic material. As described above, the first member 11, the second member 12, and the third member 13 are bonded together in this order.
  • the light L incident from the light incident surface S1 side of the first member 11 is The light passes through the first member 11, the second member 12, and the third member 13 in order, and is emitted from the light emitting surface S 2 side of the third member 13.
  • the incident direction of the light L and the bonding direction of the first member 11, the second member 12, and the third member 13 are represented as the Z axis.
  • phase difference material which comprises the 1st member 11, the 2nd member 12, and the 3rd member 13 is not restricted to a uniaxial crystal and a uniaxial organic material, Even if it uses a biaxial crystal or a biaxial organic material. Good.
  • the first member 11, the second member 12, and the third member 13 have a thickness ratio (t1: t2: t3) of 2: 2 from the light incident surface S1 side or the light output surface S2 side.
  • the thickness here is a plate thickness in the Z-axis direction in FIG. 1.
  • the thickness ratio is 2: 2: 3.
  • the thickness ratio of the first member 11, the second member 12, and the third member 13 does not have to be strictly 2: 2: 3, and the deviation from the above ratio is within a range of 2% or less, for example. That's fine.
  • the thickness of the second member 12 and the third member 13 may be 2% or less with respect to the above ratio.
  • the wavelength-selective phase difference element 10 of the present embodiment is optimized.
  • the optimization means that the polarization conversion rate of light in a predetermined wavelength band is 0% or 100%.
  • the wavelength-selective phase difference element 10 of the present embodiment has the optical axis configuration as described above, and further, the thickness of the first member 11 and the second member 12 is 200 ⁇ m, and the thickness of the third member 13 is 300 ⁇ m. By doing so, the phase difference becomes 180 ° ⁇ 3 ° with respect to light having a wavelength of 570 nm to 650 nm. Further, when the thickness of the first member 11 and the second member 12 is 240 ⁇ m and the thickness of the third member 13 is 360 ⁇ m, the phase difference is 180 ° ⁇ 3 with respect to light having wavelengths of 435 nm to 465 nm and 675 nm to 770 nm. °.
  • 3A to 3C show the wavelength selective phase difference element 10 in which the thickness ratio of the first member 11, the second member 12 and the third member 13 is 2: 2: 3 and the optical axis of each member is optimized. It is a characteristic view showing the relationship between each wavelength and the conversion rate of the polarization component (from the P polarization component to the S polarization component or from the S polarization component to the P polarization component).
  • FIG. 3A the polarization direction of the light in the red band is selectively converted.
  • FIG. 3B the polarization direction of the light in the green band is selectively converted.
  • FIG. 3C the polarization direction of light in a narrower range of green band is selectively converted.
  • the wavelength-selective phase difference element having the characteristic that the polarization direction is rotated only in the selective wavelength band is the wavelength-selective phase difference element in order to obtain a specific phase difference for each visible light.
  • the thickness of one quartz plate constituting the substrate becomes very thin, around 100 ⁇ m. For this reason, handling is difficult, and the thickness crossing for maintaining the performance is about ⁇ 1 ⁇ m.
  • a multi-order wave plate or a compound zero-order wave plate is used.
  • the multi-order wave plate is designed to obtain a predetermined phase difference at a high order in order to increase the thickness of the quartz plate to a practical level (for example, 150 ⁇ m or more).
  • the multi-order wave plate has a problem that a large phase difference shifts with respect to a slight wavelength shift, temperature change, etc., as the plate thickness increases.
  • a compound zero order wave plate is constructed by arranging the optical axes of two quartz plates made of the same material so as to be orthogonal to each other. They are offset each other.
  • the above-described wavelength-selective phase difference element is easy to handle because of its thick plate thickness.
  • a general wavelength selective phase difference element is designed without controlling the polar angle of the optical axis of the quartz plate with respect to the optical axis of incident light (the angle between the normal to the plane of the wavelength plate and the optical axis). is doing.
  • a certain input signal passes through a general wavelength selective phase difference element (phase difference plate 100) having an optical axis (here, slow axis (d)) of 135 °.
  • an image for example, a double line
  • the focus accuracy is reduced.
  • the first member 11, the second member 12, and the third member 13 are arranged in this order between the light incident surface S1 and the light emitting surface S2.
  • the thickness ratio was made to be 2: 2: 3 from the light incident surface S1 side or the light emitting surface S2 side.
  • the wavelength-selective phase difference element is composed of three layers as in this embodiment, and the thickness ratio is 2: 2: 4 (FIG. 5), 2: 2: 5 (FIG. 6).
  • FIG. 8 is a characteristic diagram showing the relationship between each wavelength and the polarization conversion rate of the wavelength selective phase difference element 10 of the present embodiment. Both are designed so that the polarization direction of light in the green band is selectively converted. 5 to 7, light in a predetermined wavelength band (here, green band) cannot be selectively converted. Further, the range in which the conversion efficiency is 0% or 100% is very narrow. On the other hand, in FIG.
  • light in a wavelength band of about 500 nm to 600 nm corresponding to the green band can be selectively converted while the light in the wavelength band other than the green band is left as it is. Further, the wavelength bandwidth where the conversion efficiency is 0% or 100% is widened.
  • the wavelength selective phase difference element 10 is bonded in the order of the first member 11, the second member 12, and the third member 13 between the light incident surface S1 and the light emitting surface S2. While comprising three members, the thickness ratio of each member was set to 2: 2: 3 from the light incident surface S1 side or the light emitting surface S2 side. Thereby, it becomes possible to design a film thickness thicker than each member which comprises a general wavelength selective phase difference element, and handling becomes easy. Further, the number of members constituting the wavelength selective phase difference element, that is, the number of layers is reduced as compared with a general wavelength selective phase difference element.
  • a seven layer structure can be used, but in the wavelength selective phase difference element 10 of the present embodiment, a three layer structure can be provided. For this reason, it becomes possible to improve surface accuracy and parallelism. Therefore, it is possible to provide a wavelength selective phase difference element that is easy to handle and has high performance, that is, capable of selectively converting the polarization direction of a predetermined wavelength.
  • the optical axes of the first member 11, the second member 12, and the third member 13 are each parallel to the plane (XY plane), that is, perpendicular to the incident light L. I did it.
  • the wavelength selective phase difference element 10 of the present embodiment for the phase difference plate of the projector 1 or the like, which will be described later, it is possible to prevent the occurrence of double lines in the image projected on the screen or the like. It becomes. Therefore, it is possible to improve the focus accuracy of the projection display device such as the projector 1.
  • the first member 11 in the present modification has a compound configuration as described above, that is, is composed of two plate-like members (plate-like members 11A and 11B).
  • the plate-like member 11A and the plate-like member 11B can be made of, for example, a uniaxial crystal or a uniaxial organic material, as in the first embodiment.
  • the plate-like member 11A and the plate-like member 11B each have an optical axis parallel to the plane (XY plane), and when the first member 11 is formed, they are bonded so that the optical axes are orthogonal to each other. ing. Thereby, the amount of phase difference shift produced by plate-like member 11A and plate-like member 11B cancels mutually.
  • the first member 11, the second member 12, and the third member 13 have a ratio of 2: 2: 3 from the light incident surface S1 side or the light emitting surface S2 side. It is configured to have a relationship.
  • each value in the first member 11 of the ratio 2: 2: 3, secondly the member 12 and the third member is composed of one plate-like member among the members 11, 12, 13. In the present member (second member 12 and third member in the present modification), this corresponds to the thickness of the plate member.
  • the member composed of two plate-like members in the present modification, the first member 11 corresponds to the thickness difference between the plate-like members.
  • the thickness (t4, t5) of the plate-like member 11A and the plate-like member 11B is preferably designed so that the difference becomes a predetermined value.
  • the thicknesses of the second member 12 and the third member 13 are 200 ⁇ m and 300 ⁇ m, respectively
  • the thicknesses of the plate-like member 11A and the plate-like member 11B constituting the first member 11 are, for example, 200 ⁇ m (plate member 11A) and 400 ⁇ m (plate member 11B).
  • the difference between the thicknesses of the plate-like member 11A and the plate-like member 11B only needs to correspond to the thickness of the second member 12, and the plate-like member 11A may be formed thicker.
  • the second member 12 or the third member 13 may have a compound configuration.
  • the difference in thickness between the two plate-like members constituting the third member 13 is 1.V. with respect to the thickness of the first member 11 (or the second member 12). It is configured to be 5 times.
  • two members (any two of the first member 11, the second member, and the third member 13) of the first member 11, the second member 12, and the third member 13 or all the members ( All of the first member 11, the second member, and the third member 13) may take a compound configuration.
  • the glass plates 21 and 22 are preferably made of, for example, aluminosilicate glass, quartz glass, white plate glass (crown glass), borosilicate glass, alkali-free glass, or the like. From the processing limit, the lower limit of the thickness of the glass plates 21 and 22 in the Z-axis direction is, for example, 0.2 mm or more. The upper limit is not particularly limited.
  • the wavelength selective phase difference element 20 of the present embodiment can be manufactured, for example, as follows.
  • a first member 11, a second member 12 and a third member 13 having an optical axis parallel to the in-plane and having a thickness ratio of 2: 2: 3 are prepared.
  • the first member 11, the second member 12, and the third member 13 are bonded together in this order using, for example, an adhesive.
  • the optical axes of the first member 11, the second member 12, and the third member 13 are adjusted to be the angle of the optical axis given as an example in the above example (FIG. 2).
  • the first member 11, the second member 12, and the third member 13 may be bonded together using, for example, optical contact bonding or intermolecular bonding, in addition to using an adhesive.
  • the glass plates 21 and 22 are bonded to the light incident surface S1 of the first member 11 and the light emitting surface S2 of the third member 13 using, for example, an adhesive. Subsequently, after the surfaces of the glass plates 21 and 22 are polished, they are cut into a predetermined shape and size. Thus, the wavelength selective phase difference element 20 shown in FIG. 10 is completed. In addition, you may perform antireflection coating etc. on the surface of the glass plates 21 and 22, for example.
  • each quartz plate is bonded by an adhesive or the like. Yes.
  • the optical distance varies due to variations in the thickness of the adhesive, and the surface accuracy and parallelism may decrease.
  • the wavelength selective phase difference element 20 of the present embodiment a so-called glass sandwich structure in which the bonded first member 11, second member and third member 13 are sandwiched between glass plates 21 and 22. Therefore, it is possible to further improve the surface accuracy and the parallelism as compared with the wavelength selective phase difference element 10 in the first embodiment. Therefore, in addition to the effects in the first embodiment, the occurrence of wavefront aberration is suppressed, and the focus accuracy in the projection display apparatus using the wavelength-selective phase difference element 20 of the present embodiment as the phase difference plate. It is possible to further improve the effect.
  • the present invention is not limited to this.
  • the same effect as that of the present embodiment can be obtained by adopting a configuration in which the wavelength selective phase difference element 10A shown in the above modification is sandwiched between the glass plates 21 and 22.
  • FIG. 11 shows a projection type equipped with the wavelength-selective phase difference element 10 (or wavelength-selective phase difference elements 10A and 20) described in the first embodiment (or the modified example and the second embodiment).
  • 2 shows a configuration of a display device (projector 1).
  • the projector 1 is a display device that generates image light by modulating and synthesizing light (illumination light) output from a light source for each color of RGB based on an image signal, and projecting an image on a screen, for example.
  • the projector 1 is a so-called three-plate type reflective projector that performs color image display using three reflective light modulation elements 41R, 41G, and 41B for red, blue, and green colors.
  • the projector 1 includes a light source 31, an integrator 32, and a dichroic mirror 33 (wavelength selection element) along the optical axis 30.
  • the light source 31 emits white light including red light (R), blue light (B), and green light (G) required for color image display.
  • a halogen lamp, a metal halide lamp, or a xenon lamp is used. Etc.
  • a solid light source such as a semiconductor laser (LD) or a light emitting diode (LED) may be used.
  • the light source 31 is not limited to one light source (white light source unit) that emits white light as described above. For example, a green light source unit that emits light in the green band and a blue light source that emits light in the blue band.
  • the integrator 32 includes a PS converter and the like, and is provided in order to make the light from the light source 31 uniform and efficiently used.
  • the dichroic mirror 33 has a function of separating white light into blue light B and other color lights (red light R, green light G).
  • the projector 1 also includes a pre-PBS (polarized beam splitter) 34, a condensing lens 36, and a dichroic mirror 38 in the order in which light travels on the optical path of red light R and green light G separated by the dichroic mirror 33. It has.
  • the projector 1 also includes a pre-PBS 35 and a condenser lens 37 in the order in which light travels on the optical path of the blue light B separated by the dichroic mirror 33.
  • the pre-PBSs 34 and 35 have a function of selectively reflecting light having a predetermined polarization component in incident light.
  • the dichroic mirror 38 has a function of separating red light R and green light G incident through the pre-PBS 34 and the condenser lens 36.
  • the pre-PBSs 34 and 35 may be arranged at any position between the condenser lens 36 and the condenser lenses 39R, 39G, and 39B, for example. At that time, mirrors are arranged at the positions of the pre-PBSs 34 and 35 shown in FIG.
  • the light modulation elements 41R, 41G, 41B are constituted by, for example, a reflective liquid crystal panel.
  • a reflective liquid crystal panel for example, a liquid crystal element such as LCOS (Liquid Crystal On Silicon) can be used.
  • Color light of a predetermined polarization component (for example, S polarization component) selected by the polarization selection surfaces of the PBSs 40R, 40G, and 40B is incident on the light modulation elements 41R, 41G, and 41B, respectively.
  • the light modulation elements 41R, 41G, and 41B modulate the incident light by controlling the polarization state, and reflect the modulated light toward the PBSs 40R, 40G, and 40B.
  • Each of the PBSs 40R, 40G, and 40B has a polarization selection surface, and on the polarization selection surface, selects (reflects) light of a predetermined polarization component (S polarization component) incident on the light modulation elements 41R, 41G, and 41B.
  • S polarization component a predetermined polarization component
  • the light having a predetermined polarization component (P polarization component) is selected (transmitted) as light for image display and emitted.
  • the PBSs 40R, 40G, and 40B reflect S-polarized component light to be incident on the light modulation elements 41R, 41G, and 41B, and return light from the light modulation elements 41R, 41G, and 41B.
  • the optical arrangement is such that the light of the P-polarized component is transmitted as the outgoing light.
  • incident light of the P-polarized light is incident from the front side of the light modulation elements 41R, 41G, and 41B.
  • the light modulation element 41R, 41G, 41B may be arranged so that the light of the S polarization component selected by reflection is used as image display light.
  • the quarter-wave plates 42R, 42G, and 42B are for correcting the polarization state between the PBSs 40R, 40G, and 40B and the light modulation elements 41R, 41G, and 41B. In contrast, a phase difference of almost 1 ⁇ 4 wavelength is generated. In addition, you may comprise this quarter wavelength plate also with the wavelength selective phase difference element of this indication.
  • the projector 1 also includes a cross dichroic prism 44, a projection lens 45, and a screen 46. Further, the wavelength selective phase difference element 10 (or the present disclosure) is provided between the cross dichroic prism 44 and the projection lens 45. Wavelength selective phase difference elements 10A, 20) are arranged. The wavelength-selective phase difference element 10 (or the wavelength-selective phase difference elements 10A and 20) may be bonded to the exit surface of the cross dichroic prism 44. Alternatively, the wavelength selective phase difference element 10 (or the wavelength selective phase difference elements 10 ⁇ / b> A and 20) may be mechanically connected to the incident side of the projection lens 45.
  • the cross dichroic prism 44 has a function of combining and emitting each color light of a predetermined polarization component selected by the PBSs 40R, 40G, and 40B.
  • the cross dichroic prism 44 has three entrance surfaces and one exit surface.
  • Spacers 43R, 43G, and 43B are disposed between the light incident surface of the cross dichroic prism 44 and the light output surfaces of the PBSs 40R, 40G, and 40B in order to prevent stress distortion due to temperature changes of these optical elements. Is provided.
  • a polarization beam splitter (PBS) or a dichroic prism may be disposed at the positions of the spacers 43R, 43G, and 43B. By placing PBS, polarization leakage is cut.
  • PBS polarization beam splitter
  • dichroic prism By placing PBS, polarization leakage is cut.
  • half-wave plates 46R and 46B are arranged between the spacers 43R and 43B and the cross dichroic prism 44, respectively. Red light and blue light reflected from the light modulation elements 41R and 41B are converted from P-polarized light components to S-polarized light components when passing through the half-wave plates 46R and 46B.
  • the projection lens 45 is disposed on the exit surface side of the cross dichroic prism 44.
  • the projection lens 45 has a function of projecting the combined light emitted from the cross dichroic prism 44 toward the screen 46.
  • the wavelength-selective phase difference element selectively converts light in a predetermined wavelength band.
  • the wavelength-selective phase difference element 10 in this application example selectively converts light in the green band. It is composed of.
  • the polarization components of each color light incident on the cross dichroic prism 44 are S-polarization components for red light and blue light, and P-polarization components for green light. Therefore, by arranging this wavelength-selective phase difference element 10 between the cross dichroic prism 44 and the projection lens 45, the light in the green band among the lights synthesized in the cross dichroic prism 44 is selectively S. It is converted into a polarization component.
  • FIG. 12 shows a projection type equipped with the wavelength-selective phase difference element 10 (or wavelength-selective phase difference elements 10A and 20) described in the first embodiment (or the modified example and the second embodiment).
  • 2 shows a configuration of a display device (projector 2).
  • the projector 2 is a so-called three-plate system that performs color image display using three transmissive liquid crystal panels (liquid crystal panel portions 64R, 64G, and 64B) as light modulation elements for red, blue, and green colors. It is a transmissive projector.
  • the projector 2 has a light source 51 that emits light.
  • the light source 51 includes, for example, a light emitter 51A that emits white light, and a concave mirror 51B that reflects the light emitted from the light emitter 51A and emits the light as substantially parallel light.
  • a halogen lamp, a metal halide lamp, or a xenon lamp is used as the light emitter 51A.
  • a solid light source such as a semiconductor laser (LD) or a light emitting diode (LED) may be used.
  • the concave mirror 51B desirably has a shape with good light collection efficiency, and has a rotationally symmetric surface shape such as a spheroidal mirror or a parabolic mirror.
  • a UV (ultraviolet) / IR (infrared) cut filter 52 for example, a UV (ultraviolet) / IR (infrared) cut filter 52, a first fly-eye lens 53A, a second fly-eye lens 53B, a PS converter 54, The 1st condensing lens 55 is arrange
  • the UV / IR cut filter 52 removes light in the ultraviolet region and infrared region contained in white light emitted from the light source 51.
  • Each of the first fly-eye lens 53A and the second fly-eye lens 53B includes a plurality of lens elements that respectively divide incident light and emit the light, whereby light in liquid crystal panel portions 64R, 64G, and 64B, which will be described later, is provided.
  • the intensity distribution is made uniform.
  • the PS converter 54 converts light emitted from the light source 51 into a P-polarized component or an S-polarized component.
  • the 1st condensing lens 55 condenses light on liquid crystal panel part 64R, 64G, 64B with the 2nd condensing lens 63R, 63G, 63B mentioned later, respectively.
  • the first condenser lens 55 has an optical axis 50.
  • a dichroic mirror 58 is provided along the optical path of other color light separated by the dichroic mirror 56.
  • the dichroic mirror 58 has a function of separating incident light into green light LG and red light LR.
  • a second condenser lens 63G and a liquid crystal panel portion 64G are sequentially arranged along the optical path of the green light LG separated by the dichroic mirror 58.
  • the second condensing lens 63G condenses the green light LG separated by the dichroic mirror 58 on the liquid crystal panel unit 64G.
  • the liquid crystal panel unit 64G has a function of spatially modulating the green light LG incident through the second condenser lens 63G according to image information.
  • a dichroic prism 65 having a function of combining the red light LR, the green light LG, and the blue light LB is provided at a position where the optical paths of the red light LR, the green light LG, and the blue light LB intersect.
  • the dichroic prism 65 has three entrance surfaces 65R, 65G, and 65B and one exit surface 65T.
  • the red light LR emitted from the liquid crystal panel unit 64R is incident on the incident surface 65R.
  • the green light LG emitted from the liquid crystal panel 64G is incident on the incident surface 65G.
  • the blue light LB emitted from the liquid crystal panel portion 64B is incident on the incident surface 65B.
  • the dichroic prism 65 combines the three color lights incident on the incident surfaces 65R, 65G, and 65B and emits them from the emission surface 65T.
  • the combined light emitted from the wavelength selective phase difference element 10 (or the wavelength selective phase difference elements 10A and 20) and the dichroic prism 65 of the present disclosure is directed toward the screen 67.
  • a projection lens 66 for projecting is provided.
  • the wavelength-selective phase difference element 10 (or the wavelength-selective phase difference elements 10A and 20) in this application example is disposed at a place other than between the dichroic prism 65 and the projection lens 66, as in the first application example. You may make it do. For example, it may be arranged between the liquid crystal panel portions 64R, 64G, and 64B and the dichroic prism 65.
  • FIG. 13 shows a projection type equipped with the wavelength-selective phase difference element 10 (or wavelength-selective phase difference elements 10A and 20) described in the first embodiment (or the modified example and the second embodiment).
  • 2 shows a configuration of a display device (projector 3).
  • the projector 3 is a so-called three-plate type reflective projector that performs color image display using three reflective light modulation elements 75R, 75G, and 75B for red, blue, and green.
  • the light source device emits white light including red light (R), blue light (B), and green light (G) required for color image display.
  • white light including red light (R), blue light (B), and green light (G) required for color image display.
  • a halogen lamp, a metal halide lamp, or a xenon lamp Etc. are configured.
  • a solid light source such as a semiconductor laser (LD) or a light emitting diode (LED) may be used.
  • LD semiconductor laser
  • LED light emitting diode
  • the color separation prism 71 includes an optical function film 71a (optical surface) that transmits light in a certain wavelength band and reflects light in the remaining wavelength band, and a prism that is bonded to the optical function film 71a. It consists of The color separation prism 71 has, for example, a light incident surface S1, and is arranged so that light of, for example, three wavelength bands enters the light incident surface S1 along the optical axis Z1. Specifically, light (Lr.Lg, Lb) in the red band, the green band, and the blue band is incident on the light incident surface S1. The light in these three wavelength bands may be such that light in any one or two wavelength bands is incident from a surface different from the light incident surface S1.
  • the polarization beam splitter 72RB guides the red band light to the light modulation element 75R, the blue band light to the light modulation element 75B, and directs each modulated red band and blue band light to the polarization beam splitter 78.
  • a wavelength-selective phase difference element 73R is disposed on the optical path between the color separation prism 71 and the polarization beam splitter 72RB.
  • a wavelength selective phase difference element 76R is disposed between the polarization beam splitter 72RB and the polarization beam splitter 78.
  • the wavelength-selective phase difference element 76R is a phase difference plate having such a characteristic that the polarization direction rotates only in a selective wavelength band.
  • the wavelength-selective phase difference element 76R the wavelength-selective phase difference element 10 (or the wavelength-selective phase difference elements 10A and 20) of the present disclosure can be used similarly to the wavelength-selective phase difference element 73R.
  • the wavelength-selective phase difference element 76R is configured to selectively rotate the polarization direction of the red band light in the red band and the blue band (the blue band light is transmitted while maintaining the polarization direction). To be configured).
  • the wavelength selective phase difference element 76R may be designed considering only performance in a band of at least two wavelengths (here, red and blue). Not all wavelengths need to be considered.
  • the polarization beam splitter 78 is an element for synthesizing (color synthesizing) the light of each wavelength band emitted from the light modulation elements 75R, 75G, and 75B and guiding it to the projection optical system 79.
  • the light emitted from the light modulation element 75G passes through the polarization beam splitter 72G and the phase difference plate 77, and the light emitted from the light modulation elements 75R and 75B passes through the polarization beam splitter 72RB and the wavelength selective phase difference element 76R.
  • Each is configured to enter the polarization beam splitter 78 from different directions.
  • the wavelength selective phase difference element 10 (or the wavelength selective phase difference elements 10A and 20) of the present disclosure is disposed.
  • the wavelength-selective phase difference element 10 is configured to selectively convert the light in the green band from the light combined by the polarization beam splitter 78 (in this case, from S-polarized component to P-polarized component). It has been done.
  • the projection optical system 79 includes a lens group for projecting light incident from the polarization beam splitter 78 via the wavelength selective phase difference element 10 onto a screen to form an image.
  • the wavelength-selective phase difference element 10 (or the wavelength-selective phase difference elements 10A and 20) may be bonded to the exit surface of the polarization beam splitter 78, as in the first and second application examples.
  • the wavelength selective phase difference element 10 (or the wavelength selective phase difference elements 10A and 20) may be mechanically connected to the incident side of the projection optical system 79.
  • the configuration of the projection display devices is merely an example, and the projection display device of the present disclosure is not limited to such a configuration.
  • the red band, the green band, and the blue band are exemplified as the plurality of wavelength bands, but some of these may be other wavelength bands. Further, the light is not limited to the three wavelength bands, and other wavelength bands, for example, light in the near infrared band may be used as another wavelength band.
  • wavelength-selective phase difference elements 10, 10A, 20 described in the first and second embodiments and modifications can be applied to a stereoscopic image display apparatus.
  • this indication can take the following structures.
  • the wavelength selective phase difference element according to (1) or (2), wherein the first member, the second member, and the third member are made of a phase difference material.
  • the glass plate is bonded to each of the light incident surface side of the first member and the light emission surface side of the third member, according to any one of (1) to (4). Wavelength selective phase difference element.
  • a light incident surface and a light exit surface A first member having a relationship of being in a ratio of 2: 2: 3 from the light incident surface side or the light output surface side, which is sequentially bonded between the light incident surface and the light output surface; Two members and a third member, At least one of the first member, the second member, and the third member is composed of two plate-like members, Each value in the ratio of the first member, the second member, and the third member corresponds to the thickness of each plate member, and includes two plate members. In some cases, a wavelength selective phase difference element corresponding to the thickness difference.
  • One or a plurality of light source units that emit light of a plurality of different wavelength bands; Of the light emitted from the light source unit, a wavelength selection element that transmits or reflects light of a predetermined wavelength component; A plurality of light modulation elements that respectively modulate light of the plurality of wavelength bands; A color synthesizing element that synthesizes light of each wavelength band emitted from the plurality of modulation elements; A projection optical system for projecting light emitted from the color synthesis element; A wavelength selective phase difference element disposed on the light emitting side of the wavelength selective element; The wavelength selective phase difference element is: A light incident surface and a light exit surface; A first member, a second member, and a third member, which are sequentially bonded between the light incident surface and the light emitting surface; The projection display
  • Display device (10) The projection display device according to (8) or (9), wherein the wavelength-selective phase difference element selectively converts light in a predetermined wavelength band among the plurality of wavelength bands.
  • Said 1 light source part is a projection type display apparatus in any one of said (8) thru
  • the plurality of light source units include a green light source unit that emits green band light, a blue light source unit that emits blue band light, and a red light source unit that emits red band light.
  • the projection display device according to any one of (11).
  • the projection display device according to any one of (8) to (13), wherein the color composition element is a polarization beam splitter, a dichroic prism, or a dichroic mirror.
  • One or a plurality of light source units that emit light of a plurality of different wavelength bands; Of the light emitted from the light source unit, a wavelength selection element that transmits or reflects light of a predetermined wavelength component; A plurality of light modulation elements that respectively modulate light of the plurality of wavelength bands; A color synthesizing element that synthesizes light of each wavelength band emitted from the plurality of modulation elements; A projection optical system for projecting light emitted from the color synthesis element; A wavelength selective phase difference element disposed on the light emitting side of the wavelength selective element; The wavelength selective phase difference element is: A light incident surface and a light exit surface; A first member having a relationship of being in a ratio of 2: 2: 3 from the light incident surface side or the light output surface side, which is sequentially bonded between the light incident surface and the light output surface; Two members and a third member, At least one of the first member, the second member, and the third member is composed of two plate-like members, Each value in the ratio of the first member

Abstract

A wavelength-selective retardation element in a first photoelectric conversion element according to an embodiment of the present disclosure includes: a light incident surface and a light exit surface; and a first member, a second member, and a third member sequentially laminated between the light incident surface and the light exit surface. The thickness ratio of the first member, the second member, and the third member is 2 : 2 : 3 from the light incident surface side or the light exit surface side.

Description

波長選択性位相差素子および投射型表示装置Wavelength selective phase difference element and projection display device
　本開示は、位相差材料によって構成された波長選択性位相差素子およびこれを備えた投射型表示装置に関する。 The present disclosure relates to a wavelength-selective phase difference element formed of a phase difference material and a projection display device including the same.
　近年、例えば、ＬＣＯＳ(Liquid Crystal On Silicon)と呼ばれる反射型の液晶表示素子と、偏光ビームスプリッタ（ＰＢＳ）とを用いたプロジェクタ（投射型表示装置）が普及している。このような投射型表示装置では、Ｒ（赤），Ｇ（緑），Ｂ（青）の３原色の光が色毎に分離され、各色に対応する反射型液晶表示素子に導かれる。Ｒ，Ｇ，Ｂの３原色の光の偏光方向は、例えば、波長選択性をもつ位相差板（波長選択性位相差素子）によって制御されている（例えば、特許文献１）。 In recent years, for example, projectors (projection display devices) using a reflective liquid crystal display element called LCOS (Liquid Crystal On Silicon) and a polarization beam splitter (PBS) have become widespread. In such a projection display device, light of the three primary colors R (red), G (green), and B (blue) is separated for each color and guided to a reflective liquid crystal display element corresponding to each color. The polarization directions of light of the three primary colors R, G, and B are controlled by, for example, a phase difference plate (wavelength selective phase difference element) having wavelength selectivity (for example, Patent Document 1).
　一般的な投射型表示装置では、波長選択性位相差素子は、例えば、クロスダイクロイックプリズムと投影レンズとの間に配設されており、例えば、青色帯域の光および赤色帯域の光を選択的に９０度回転させて出射する。 In a general projection display device, a wavelength selective phase difference element is disposed, for example, between a cross dichroic prism and a projection lens, and selectively selects, for example, blue band light and red band light. It is rotated 90 degrees and emitted.
特開２００７－３２２７０２号公報JP 2007-322702 A
　ところで、可視光ごとに特定の位相差を得る（例えば、緑色帯域と赤色帯域、あるいは、緑色帯域と青色帯域で位相差を得る）ためには、波長選択性位相差素子を構成する１枚の複屈折材料（例えば、水晶板）の板厚は、１００μｍ前後と非常に薄い厚みとなる。このため、取り扱いが難しく、また、性能を維持する厚み交差が±１μｍ程度となるため、製造歩留まりが低くなる。よって、取り扱いやすく、高い性能を有する波長選択性位相差素子の開発が望まれている。 By the way, in order to obtain a specific phase difference for each visible light (for example, to obtain a phase difference between a green band and a red band, or between a green band and a blue band), one piece of a wavelength selective phase difference element is formed. The thickness of the birefringent material (for example, a quartz plate) is as very thin as around 100 μm. For this reason, handling is difficult, and since the thickness crossing for maintaining the performance is about ± 1 μm, the manufacturing yield is lowered. Therefore, development of a wavelength-selective phase difference element that is easy to handle and has high performance is desired.
　取り扱いやすく、高い性能を有する波長選択性位相差素子および投射型表示装置を提供することが望ましい。 It is desirable to provide a wavelength-selective phase difference element and a projection display device that are easy to handle and have high performance.
　本開示の一実施形態の第１の波長選択性位相差素子は、光入射面および光出射面と、光入射面と光出射面との間に順に貼り合わされた第１部材、第２部材および第３部材とを有するものであり、第１部材、第２部材および第３部材は、その厚み比が光入射面の側または光出射面の側から２：２：３となっている。 A first wavelength selective phase difference element according to an embodiment of the present disclosure includes a light incident surface and a light output surface, and a first member, a second member, and a second member, which are sequentially bonded between the light incident surface and the light output surface. The thickness ratio of the first member, the second member, and the third member is 2: 2: 3 from the light incident surface side or the light emitting surface side.
　本開示の一実施形態の第１の投射型表示装置は、互いに異なる複数の波長帯域の光を出射する１または複数の光源部と、光源部から出射された光のうち、所定波長成分の光を透過または反射する波長選択素子と、複数の波長帯域の光をそれぞれ変調する複数の光変調素子と、複数の変調素子から出射された各波長帯域の光を合成する色合成素子と、色合成素子から出射された光を投射する投影光学系と、波長選択素子の光出射側に配置された波長選択性位相差素子とを備えたものであり、この波長選択性位相差素子として、上記本開示の一実施形態の第１の波長選択性位相差素子を有するものである。 A first projection display device according to an embodiment of the present disclosure includes one or a plurality of light source units that emit light having a plurality of different wavelength bands, and light having a predetermined wavelength component among the light emitted from the light source unit. Selection element that transmits or reflects light, a plurality of light modulation elements that respectively modulate light in a plurality of wavelength bands, a color composition element that combines light in each wavelength band emitted from the plurality of modulation elements, and color composition A projection optical system for projecting light emitted from the element, and a wavelength selective phase difference element disposed on the light emission side of the wavelength selection element. It has the 1st wavelength selective phase contrast element of one embodiment of an indication.
　本開示の一実施形態の第２の波長選択性位相差素子は、光入射面および光出射面と、光入射面と光出射面との間に順に貼り合わされると共に、光入射面の側または光出射面の側から２：２：３の比となる関係を有する第１部材、第２部材および第３部材とを有するものであり、第１部材、第２部材および第３部材は、少なくとも１つが２枚の板状部材からなり、比の第１部材、第２部材および第３部材における各値は、それぞれが、１枚の板状部材からなる場合にはその厚みに相当し、２枚の板状部材からなる場合にはその厚み差に相当する。 The second wavelength-selective phase difference element according to an embodiment of the present disclosure is bonded in order between the light incident surface and the light emitting surface, and the light incident surface and the light emitting surface. The first member, the second member, and the third member have a relationship of 2: 2: 3 from the light emitting surface side, and the first member, the second member, and the third member are at least One is composed of two plate-like members, and each value of the ratio of the first member, the second member, and the third member corresponds to the thickness of each of the plate-like members, and 2 When it consists of a sheet-like member, it corresponds to the thickness difference.
　本開示の一実施形態の第２の投射型表示装置は、互いに異なる複数の波長帯域の光を出射する１または複数の光源部と、光源部から出射された光のうち、所定波長成分の光を透過または反射する波長選択素子と、複数の波長帯域の光をそれぞれ変調する複数の光変調素子と、複数の変調素子から出射された各波長帯域の光を合成する色合成素子と、色合成素子から出射された光を投射する投影光学系と、波長選択素子の光出射側に配置された波長選択性位相差素子とを備えたものであり、この波長選択性位相差素子として、上記本開示の一実施形態の第２の波長選択性位相差素子を有するものである。 A second projection display device according to an embodiment of the present disclosure includes one or a plurality of light source units that emit light having a plurality of different wavelength bands, and light having a predetermined wavelength component out of the light emitted from the light source unit. Selection element that transmits or reflects light, a plurality of light modulation elements that respectively modulate light in a plurality of wavelength bands, a color composition element that combines light in each wavelength band emitted from the plurality of modulation elements, and color composition A projection optical system for projecting light emitted from the element, and a wavelength selective phase difference element disposed on the light emission side of the wavelength selection element. It has the 2nd wavelength selective phase contrast element of one embodiment of an indication.
　本開示の一実施形態の第１の波長選択性位相差素子および一実施形態の第１の投射型表示装置では、光入射面と光出射面との間で、第１部材、第２部材および第３部材の順に貼り合わされた各部材の厚み比が、光入射面側または光出射面側から２：２：３となるようにした。また、本開示の一実施形態の第２の波長選択性位相差素子および一実施形態の第２の投射型表示装置では、光入射面と光出射面との間で順に張り合わされた第１部材、第２部材および第３部材が、光入射面の側または光出射面の側から２：２：３の比となる関係を有すると共に、すくなくとも１つの部材が、２枚の板状部材からなるようにした。なお、２：２：３の比の第１部材、第２部材および第３部材における各値は、それぞれが、１枚の板状部材からなる場合にはその厚みに相当し、２枚の板状部材からなる場合にはその厚み差に相当する。上記構成とすることにより、一般的な波長選択性位相差素子を構成する各部材よりも膜厚を厚く設計することが可能となる。また、一般的な波長選択性位相差素子と比較して、構成部材の数を削減することが可能となる。 In the first wavelength-selective phase difference element according to the embodiment of the present disclosure and the first projection display device according to the embodiment, the first member, the second member, and the light-emitting surface between the light incident surface and the light emitting surface. The thickness ratio of each member bonded in the order of the third member was set to 2: 2: 3 from the light incident surface side or the light emission surface side. Further, in the second wavelength-selective phase difference element according to the embodiment of the present disclosure and the second projection display device according to the embodiment, the first member bonded in order between the light incident surface and the light emitting surface. The second member and the third member have a relationship of a ratio of 2: 2: 3 from the light incident surface side or the light emitting surface side, and at least one member is composed of two plate-like members. I did it. In addition, each value in the ratio of 2: 2: 3 in the first member, the second member, and the third member corresponds to the thickness in the case where each of the first member, the second member, and the third member is composed of one plate-like member, and the two plates This is equivalent to the thickness difference in the case of the shape member. By setting it as the said structure, it becomes possible to design a film thickness thicker than each member which comprises a general wavelength selective phase difference element. Further, the number of constituent members can be reduced as compared with a general wavelength selective phase difference element.
　本開示の一実施形態の第１および第２の波長選択性位相差素子ならびに一実施形態の第１および第２の投射型表示装置によれば、光入射面側からこの順に貼り合わされる第１部材、第２部材および第３部材が、光入射面側または光出射面側から２：２：３の比を有するようにしたので、各部材の膜厚を厚く設計することが可能となる。よって、各部材の取り扱いが容易になる。また、一般的な波長選択性位相差素子と比較して、構成部材の数が削減されるため、面精度および平行度を向上させることが可能となる。よって、取り扱いやすく、高い性能を有する波長選択性位相差素子を提供することが可能となる。 According to the first and second wavelength selective phase difference elements of the embodiment of the present disclosure and the first and second projection display devices of the embodiment, the first bonded in this order from the light incident surface side. Since the member, the second member, and the third member have a ratio of 2: 2: 3 from the light incident surface side or the light output surface side, it is possible to design the film thickness of each member to be thick. Therefore, handling of each member becomes easy. Further, since the number of constituent members is reduced as compared with a general wavelength selective phase difference element, it is possible to improve surface accuracy and parallelism. Therefore, it is possible to provide a wavelength-selective phase difference element that is easy to handle and has high performance.
　なお、ここに記載された効果は必ずしも限定されるものではなく、本開示中に記載されたいずれの効果であってもよい。 In addition, the effect described here is not necessarily limited, and may be any effect described in the present disclosure.
本開示の第１の実施の形態に係る波長選択性位相差素子の構成の一例を表す斜視図である。It is a perspective view showing an example of composition of a wavelength selective phase contrast element concerning a 1st embodiment of this indication. 図１に示した波長選択性位相差素子を構成する各部材の光学軸の一例を表したものである。2 illustrates an example of an optical axis of each member constituting the wavelength selective phase difference element illustrated in FIG. 1. 図１に示した波長選択性位相差素子の一例における各波長と偏光変換率との関係を表す特性図である。It is a characteristic view showing the relationship between each wavelength and polarization conversion rate in an example of the wavelength selective phase difference element shown in FIG. 図１に示した波長選択性位相差素子の他の例における各波長と偏光変換率との関係を表す特性図である。It is a characteristic view showing the relationship between each wavelength and polarization conversion rate in the other example of the wavelength selective phase difference element shown in FIG. 図１に示した波長選択性位相差素子の他の例における各波長と偏光変換率との関係を表す特性図である。It is a characteristic view showing the relationship between each wavelength and polarization conversion rate in the other example of the wavelength selective phase difference element shown in FIG. 一般的な波長選択性位相差素子の性能を説明する模式図である。It is a schematic diagram explaining the performance of a general wavelength selective phase difference element. 比較例１における波長選択性位相差素子の波長と偏光変換率との関係を表す特性図である。It is a characteristic view showing the relationship between the wavelength of a wavelength selective phase difference element in comparative example 1, and a polarization conversion rate. 比較例２における波長選択性位相差素子の波長と偏光変換率との関係を表す特性図である。6 is a characteristic diagram illustrating a relationship between a wavelength of a wavelength selective phase difference element and a polarization conversion rate in Comparative Example 2. FIG. 比較例３における波長選択性位相差素子の波長と偏光変換率との関係を表す特性図である。It is a characteristic view showing the relationship between the wavelength of a wavelength selective phase difference element in comparative example 3, and a polarization conversion rate. 本開示の波長選択性位相差素子の波長と偏光変換率との関係を表す特性図である。It is a characteristic view showing the relationship between the wavelength of the wavelength selective phase difference element of this indication, and polarization conversion rate. 本開示の変形例に係る波長選択性位相差素子の構成の一例を表す斜視図である。It is a perspective view showing an example of composition of a wavelength selective phase contrast element concerning a modification of this indication. 本開示の第２の実施の形態に係る波長選択性位相差素子の構成の一例を表す斜視図である。It is a perspective view showing an example of composition of a wavelength selective phase contrast element concerning a 2nd embodiment of this indication. 適用例１に係る投射型表示装置の構成を表す模式図である。10 is a schematic diagram illustrating a configuration of a projection display device according to application example 1. FIG. 適用例２に係る投射型表示装置の構成を表す模式図である。It is a schematic diagram showing the structure of the projection type display apparatus concerning the application example 2. FIG. 適用例３に係る投射型表示装置の構成を表す模式図である。It is a schematic diagram showing the structure of the projection type display apparatus concerning the application example 3. FIG.
　以下、本開示の実施の形態について、図面を参照して詳細に説明する。なお、説明は以下の順序で行う。
１．第１の実施の形態（光入射面側または光出射面側からの厚み比が２：２：３である３種の部材により構成された例）
　　１－１．波長選択性位相差素子の構成
　　１－２．作用・効果
２．変形例（３種の部材のち１種を２層構造とした例）
３．第２の実施の形態（波長選択性位相差素子をガラス板で挟んだ例）
　　３－１．波長選択性位相差素子の構成
　　３－２．波長選択性位相差素子の製造方法
　　３－３．作用・効果
４．適用例 Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The description will be given in the following order.
1. 1st Embodiment (example comprised by 3 types of members whose thickness ratio from the light-incidence surface side or the light-projection surface side is 2: 2: 3)
1-1. Configuration of wavelength selective phase difference element 1-2. Action / Effect Modified example (example in which one of the three members has a two-layer structure)
3. Second embodiment (example in which wavelength selective phase difference element is sandwiched between glass plates)
3-1. Configuration of wavelength selective phase difference element 3-2. Manufacturing method of wavelength selective phase difference element 3-3. Action / effect 4. Application examples
＜１．第１の実施の形態＞
　図１は、本開示の第１の実施の形態に係る波長選択性位相差素子（波長選択性位相差素子１０）の構成を斜視的に表したものである。この波長選択性位相差素子１０は、例えば、後述する投射型表示装置（例えば、プロジェクタ１（図１１））に用いられ、選択的な波長帯域においてのみ偏光方向が回転するような特性を有する位相差板である。本実施の形態の波長選択性位相差素子１０は、光入射面Ｓ１および光出射面Ｓ２を有すると共に、この光入射面Ｓ１側から、第１部材１１、第２部材１２および第３部材１３がこの順に貼り合わされた構成を有する。 <1. First Embodiment>
FIG. 1 is a perspective view of a configuration of a wavelength selective phase difference element (wavelength selective phase difference element 10) according to the first embodiment of the present disclosure. The wavelength selective phase difference element 10 is used in, for example, a projection type display device (for example, the projector 1 (FIG. 11)) described later, and has such a characteristic that the polarization direction rotates only in a selective wavelength band. It is a phase difference plate. The wavelength-selective phase difference element 10 of the present embodiment has a light incident surface S1 and a light exit surface S2, and the first member 11, the second member 12, and the third member 13 are arranged from the light incident surface S1 side. It has the structure bonded in this order.
（１－１．波長選択性位相差素子の構成）
　本実施の形態の波長選択性位相差素子１０は、上記のように、選択的な波長帯域（例えば、赤色帯域、緑色帯域あるいは青色帯域）において偏光方向が回転するような特性を有するものである。 (1-1. Configuration of wavelength selective phase difference element)
As described above, the wavelength-selective phase difference element 10 of the present embodiment has a characteristic that the polarization direction rotates in a selective wavelength band (for example, a red band, a green band, or a blue band). .
　第１部材１１、第２部材１２および第３部材１３は、所定の厚みを有する板状部材であり、位相差材料、例えば、一軸性結晶または一軸性有機材料によって構成されたものである。第１部材１１、第２部材１２および第３部材１３は、上記のように、この順に貼り合わされたものであり、例えば、第１部材１１の光入射面Ｓ１側から入射した光Ｌは、第１部材１１、第２部材１２および第３部材１３を順に透過して、第３部材１３の光出射面Ｓ２側から出射される。図１では、光Ｌの入射方向および第１部材１１、第２部材１２および第３部材１３の貼り合わせ方向をＺ軸として表している。 The first member 11, the second member 12, and the third member 13 are plate-like members having a predetermined thickness, and are made of a phase difference material, for example, a uniaxial crystal or a uniaxial organic material. As described above, the first member 11, the second member 12, and the third member 13 are bonded together in this order. For example, the light L incident from the light incident surface S1 side of the first member 11 is The light passes through the first member 11, the second member 12, and the third member 13 in order, and is emitted from the light emitting surface S 2 side of the third member 13. In FIG. 1, the incident direction of the light L and the bonding direction of the first member 11, the second member 12, and the third member 13 are represented as the Z axis.
　なお、第１部材１１、第２部材１２および第３部材１３を構成する位相差材料は、一軸性結晶および一軸性有機材料に限らず、二軸性結晶または二軸性有機材料を用いてもよい。 In addition, the phase difference material which comprises the 1st member 11, the 2nd member 12, and the 3rd member 13 is not restricted to a uniaxial crystal and a uniaxial organic material, Even if it uses a biaxial crystal or a biaxial organic material. Good.
　本実施の形態では、第１部材１１、第２部材１２および第３部材１３は、その厚み比（ｔ１：ｔ２：ｔ３）が、光入射面Ｓ１側または光出射面Ｓ２側から２：２：３となっている。なお、ここでいう厚みとは、図１におけるＺ軸方向の板厚のことであり、図１では、光入射面Ｓ１側から、即ち、第１部材１１、第２部材１２、第３部材１３の順に２：２：３の厚み比となっている場合を示している。また、第１部材１１、第２部材１２および第３部材１３の厚み比は、厳密に２：２：３である必要はなく、上記比率に対するズレが、例えば、２％以下の範囲内であればよい。具体的には、例えば、第１部材１１の厚みを基準とした場合、第２部材１２および第３部材１３の厚みが、上記比率に対して２％以下であればよい。 In the present embodiment, the first member 11, the second member 12, and the third member 13 have a thickness ratio (t1: t2: t3) of 2: 2 from the light incident surface S1 side or the light output surface S2 side. 3 In addition, the thickness here is a plate thickness in the Z-axis direction in FIG. 1. In FIG. 1, from the light incident surface S1 side, that is, the first member 11, the second member 12, and the third member 13. In this order, the thickness ratio is 2: 2: 3. Further, the thickness ratio of the first member 11, the second member 12, and the third member 13 does not have to be strictly 2: 2: 3, and the deviation from the above ratio is within a range of 2% or less, for example. That's fine. Specifically, for example, when the thickness of the first member 11 is used as a reference, the thickness of the second member 12 and the third member 13 may be 2% or less with respect to the above ratio.
　第１部材１１、第２部材１２および第３部材１３は、それぞれ面（ＸＹ平面）内に対して平行な光学軸を有する。本実施の形態では、第１部材１１、第２部材１２および第３部材１３は、互いに異なる光学軸を有することが好ましい。第１部材１１、第２部材１２および第３部材１３の各光学軸の一例としては、以下の組み合わせが挙げられる。例えば、図２に示したように、第１部材１１の光学軸に対する垂線と、基準面との成す角θ１が、７３°、第２部材１２の光学軸に対する垂線と、基準面との成す角θ２が３７°、第３部材１３の光学軸に対する垂線と、基準面との成す角θ３が－４５°である。上記角度とすることで、本実施の形態の波長選択性位相差素子１０は最適化される。なお、ここで最適化とは、所定の波長帯域の光の偏光変換率が０％または１００％となることである。 The first member 11, the second member 12, and the third member 13 each have an optical axis parallel to the plane (XY plane). In the present embodiment, it is preferable that the first member 11, the second member 12, and the third member 13 have different optical axes. Examples of the optical axes of the first member 11, the second member 12, and the third member 13 include the following combinations. For example, as shown in FIG. 2, the angle θ1 formed between the perpendicular to the optical axis of the first member 11 and the reference surface is 73 °, and the angle formed between the normal to the optical axis of the second member 12 and the reference surface. θ2 is 37 °, and the angle θ3 formed between the perpendicular to the optical axis of the third member 13 and the reference plane is −45 °. By setting the angle, the wavelength-selective phase difference element 10 of the present embodiment is optimized. Here, the optimization means that the polarization conversion rate of light in a predetermined wavelength band is 0% or 100%.
　例えば、本実施の形態の波長選択性位相差素子１０は、上記のような光学軸の構成とし、さらに、第１部材１１および第２部材１２の厚みを２００μｍ、第３部材１３の厚みを３００μｍとすることで、波長５７０ｎｍ～６５０ｎｍの光に対して位相差が１８０°±３°となる。また、第１部材１１および第２部材１２の厚みを２４０μｍ、第３部材１３の厚みを３６０μｍとした場合には、波長４３５ｎｍ～４６５ｎｍおよび６７５ｎｍ～７７０ｎｍの光に対して位相差が１８０°±３°となる。 For example, the wavelength-selective phase difference element 10 of the present embodiment has the optical axis configuration as described above, and further, the thickness of the first member 11 and the second member 12 is 200 μm, and the thickness of the third member 13 is 300 μm. By doing so, the phase difference becomes 180 ° ± 3 ° with respect to light having a wavelength of 570 nm to 650 nm. Further, when the thickness of the first member 11 and the second member 12 is 240 μm and the thickness of the third member 13 is 360 μm, the phase difference is 180 ° ± 3 with respect to light having wavelengths of 435 nm to 465 nm and 675 nm to 770 nm. °.
　図３Ａ～図３Ｃは、第１部材１１、第２部材１２および第３部材１３の厚み比を２：２：３とし、さらに各部材の光学軸を最適化した波長選択性位相差素子１０の各波長と偏光成分（Ｐ偏光成分からＳ偏光成分へ、あるいは、Ｓ偏光成分からＰ偏光成分へ）の変換率との関係を表した特性図である。図３Ａでは、赤色帯域の光の偏光方向が選択的に変換されている。図３Ｂでは、緑色帯域の光の偏光方向が選択的に変換されている。図３Ｃでは、さらに狭い範囲の緑色帯域の光の偏光方向が選択的に変換されている。このように上記構成とすることにより、所定の波長帯域の光の偏光方向を、ＸＹ平面に対して９０°回転させることが可能となると共に、変換効率が０％または１００％となる波長帯域幅を広くすることが可能となる。また、所定の波長帯域以外の光は偏光方向を維持したまま透過するように構成されている。即ち、所定の波長帯域の光の偏光方向を選択的に変換することが可能となる。 3A to 3C show the wavelength selective phase difference element 10 in which the thickness ratio of the first member 11, the second member 12 and the third member 13 is 2: 2: 3 and the optical axis of each member is optimized. It is a characteristic view showing the relationship between each wavelength and the conversion rate of the polarization component (from the P polarization component to the S polarization component or from the S polarization component to the P polarization component). In FIG. 3A, the polarization direction of the light in the red band is selectively converted. In FIG. 3B, the polarization direction of the light in the green band is selectively converted. In FIG. 3C, the polarization direction of light in a narrower range of green band is selectively converted. By adopting the above configuration, the wavelength bandwidth in which the polarization direction of light in a predetermined wavelength band can be rotated by 90 ° with respect to the XY plane, and the conversion efficiency is 0% or 100%. Can be widened. In addition, light other than the predetermined wavelength band is configured to transmit while maintaining the polarization direction. That is, it becomes possible to selectively convert the polarization direction of light in a predetermined wavelength band.
（１－２．作用・効果）
　前述したように、選択的な波長帯域においてのみ偏光方向が回転するような特性を有する波長選択性位相差素子は、可視光ごとに特定の位相差を得るためには、波長選択性位相差素子を構成する１枚の水晶板の板厚が１００μｍ前後と非常に薄くなる。このため、取り扱いが難しく、また、性能を維持する厚み交差が±１μｍ程度となり、実際には、例えば、マルチオーダー波長板やコンパウンドゼロオーダー波長板が用いられている。 (1-2. Action and effect)
As described above, the wavelength-selective phase difference element having the characteristic that the polarization direction is rotated only in the selective wavelength band is the wavelength-selective phase difference element in order to obtain a specific phase difference for each visible light. The thickness of one quartz plate constituting the substrate becomes very thin, around 100 μm. For this reason, handling is difficult, and the thickness crossing for maintaining the performance is about ± 1 μm. In practice, for example, a multi-order wave plate or a compound zero-order wave plate is used.
　マルチオーダー波長板は、水晶板の板厚を実用的なレベル（例えば１５０μｍ以上）まで厚くするために、高次で所定の位相差が得られるように設計されている。しかしながら、マルチオーダーの波長板では、板厚が厚くなる分、僅かな波長シフトや温度変化等に対して大きな位相差ズレが生じるという問題がある。コンパウンドゼロオーダー波長板は、マルチオーダーで製造された２枚の同じ材質の水晶板の光軸が互いに直交するように配置して構成されたものであり、各水晶板で生じる位相差シフト量が互いに相殺されるようになっている。 The multi-order wave plate is designed to obtain a predetermined phase difference at a high order in order to increase the thickness of the quartz plate to a practical level (for example, 150 μm or more). However, the multi-order wave plate has a problem that a large phase difference shifts with respect to a slight wavelength shift, temperature change, etc., as the plate thickness increases. A compound zero order wave plate is constructed by arranging the optical axes of two quartz plates made of the same material so as to be orthogonal to each other. They are offset each other.
　上記のような波長選択性位相差素子では、板厚が厚い分、取り扱いは容易になる。しかしながら、コンパウンドゼロオーダー波長板では部材点数が２倍になるため、コストおよび加工費が増大する。また、いずれの波長板も入射角度依存性を有する。更に、一般的な波長選択性位相差素子では、入射光の光軸に対する水晶板の光学軸の極角（波長板の平面に対する法線と、光学軸とのなす角）を制御せずに設計している。このため、図４に示したように、ある入力信号が光学軸（ここでは、遅相軸（ｄ））１３５°を有する一般的な波長選択性位相差素子（位相差板１００）を介して投射されると、スクリーンには、１３５°方向にずれた像（例えば、二重線）が投影され、フォーカス精度が低下する。 The above-described wavelength-selective phase difference element is easy to handle because of its thick plate thickness. However, in the compound zero order wave plate, since the number of members is doubled, the cost and the processing cost are increased. In addition, any wave plate has an incident angle dependency. Furthermore, a general wavelength selective phase difference element is designed without controlling the polar angle of the optical axis of the quartz plate with respect to the optical axis of incident light (the angle between the normal to the plane of the wavelength plate and the optical axis). is doing. For this reason, as shown in FIG. 4, a certain input signal passes through a general wavelength selective phase difference element (phase difference plate 100) having an optical axis (here, slow axis (d)) of 135 °. When projected, an image (for example, a double line) shifted in the 135 ° direction is projected onto the screen, and the focus accuracy is reduced.
　これに対して、本実施の形態の波長選択性位相差素子１０では、光入射面Ｓ１と光出射面Ｓ２との間で、第１部材１１、第２部材１２および第３部材１３をこの順に貼り合わせ、その厚み比が、光入射面Ｓ１側または光出射面Ｓ２側から２：２：３となるようにした。 On the other hand, in the wavelength selective phase difference element 10 of the present embodiment, the first member 11, the second member 12, and the third member 13 are arranged in this order between the light incident surface S1 and the light emitting surface S2. The thickness ratio was made to be 2: 2: 3 from the light incident surface S1 side or the light emitting surface S2 side.
　図５～図７は、波長選択性位相差素子を本実施の形態のように３層から構成し、その厚み比を、２：２：４（図５）、２：２：５（図６）、２：３：２（図７）に構成した場合の各波長と偏光変換率との関係を表した特性図である。図８は、本実施の形態の波長選択性位相差素子１０の各波長と偏光変換率との関係を表した特性図である。なお、いずれも、緑色帯域の光の偏光方向が選択的に変換されるように設計している。図５～図７では、所定の波長帯域（ここでは、緑色帯域）の光を選択的に変換できていない。また、変換効率が０％または１００％となる範囲が非常に狭い。これに対して、図８では、緑色帯域以外の波長帯域の光はそのままに、緑色帯域に相当する約５００ｎｍ～６００ｎｍの波長帯域の光を選択的に変換できている。また、変換効率が０％または１００％となる波長帯域幅が広くなっている。 5 to 7, the wavelength-selective phase difference element is composed of three layers as in this embodiment, and the thickness ratio is 2: 2: 4 (FIG. 5), 2: 2: 5 (FIG. 6). ) Is a characteristic diagram showing the relationship between each wavelength and the polarization conversion rate in the case of 2: 3: 2 (FIG. 7). FIG. 8 is a characteristic diagram showing the relationship between each wavelength and the polarization conversion rate of the wavelength selective phase difference element 10 of the present embodiment. Both are designed so that the polarization direction of light in the green band is selectively converted. 5 to 7, light in a predetermined wavelength band (here, green band) cannot be selectively converted. Further, the range in which the conversion efficiency is 0% or 100% is very narrow. On the other hand, in FIG. 8, light in a wavelength band of about 500 nm to 600 nm corresponding to the green band can be selectively converted while the light in the wavelength band other than the green band is left as it is. Further, the wavelength bandwidth where the conversion efficiency is 0% or 100% is widened.
　以上、本実施の形態では、波長選択性位相差素子１０を、光入射面Ｓ１と光出射面Ｓ２との間で、第１部材１１、第２部材１２および第３部材１３の順に貼り合わされる３つの部材で構成すると共に、各部材の厚み比を、光入射面Ｓ１側または光出射面Ｓ２側から２：２：３となるようにした。これにより、一般的な波長選択性位相差素子を構成する各部材よりも膜厚を厚く設計することが可能となり、取り扱いが容易になる。また、一般的な波長選択性位相差素子と比較して、波長選択性位相差素子を構成する部材の数、即ち層数が削減される。具体的には、一般的な波長選択性位相差素子では、７層構造となるところを、本実施の形態の波長選択性位相差素子１０では、３層構造とすることができる。このため、面精度および平行度を向上させることが可能となる。よって、取り扱い易く、高い性能、即ち、所定の波長の偏光方向を選択的に変換することが可能な波長選択性位相差素子を提供することが可能となる。 As described above, in the present embodiment, the wavelength selective phase difference element 10 is bonded in the order of the first member 11, the second member 12, and the third member 13 between the light incident surface S1 and the light emitting surface S2. While comprising three members, the thickness ratio of each member was set to 2: 2: 3 from the light incident surface S1 side or the light emitting surface S2 side. Thereby, it becomes possible to design a film thickness thicker than each member which comprises a general wavelength selective phase difference element, and handling becomes easy. Further, the number of members constituting the wavelength selective phase difference element, that is, the number of layers is reduced as compared with a general wavelength selective phase difference element. Specifically, in a general wavelength selective phase difference element, a seven layer structure can be used, but in the wavelength selective phase difference element 10 of the present embodiment, a three layer structure can be provided. For this reason, it becomes possible to improve surface accuracy and parallelism. Therefore, it is possible to provide a wavelength selective phase difference element that is easy to handle and has high performance, that is, capable of selectively converting the polarization direction of a predetermined wavelength.
　また、本実施の形態では、第１部材１１、第２部材１２および第３部材１３の光学軸が、それぞれ面（ＸＹ平面）内に対して平行、即ち、入射光Ｌに対して垂直になるようにした。これにより、例えば後述するプロジェクタ１等の位相差板に、本実施の形態の波長選択性位相差素子１０を用いることで、スクリーン等に投影される画像における二重線の発生を防ぐことが可能となる。よって、プロジェクタ１等の投射型表示装置のフォーカス精度を向上させることが可能となる。 In the present embodiment, the optical axes of the first member 11, the second member 12, and the third member 13 are each parallel to the plane (XY plane), that is, perpendicular to the incident light L. I did it. Thereby, for example, by using the wavelength selective phase difference element 10 of the present embodiment for the phase difference plate of the projector 1 or the like, which will be described later, it is possible to prevent the occurrence of double lines in the image projected on the screen or the like. It becomes. Therefore, it is possible to improve the focus accuracy of the projection display device such as the projector 1.
　次に、本開示の変形例および第２の実施の形態について説明する。以下では、上記第１の実施の形態と同様の構成要素については同一の符号を付し、適宜その説明を省略する。 Next, a modified example and the second embodiment of the present disclosure will be described. In the following, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted as appropriate.
＜２．変形例＞
　図９は、上記第１の実施の形態の変形例に係る波長選択性位相差素子（波長選択性位相差素子１０Ａ）の構成を斜視的に表したものである。この波長選択性位相差素子１０Ａは、第１の実施の形態と同様に、例えば、後述する投射型表示装置（例えば、プロジェクタ１）に用いられ、選択的な波長帯域においてのみ偏光方向が回転するような特性を持つ位相差板である。本変形例の波長選択性位相差素子１０Ａは、貼り合わされた第１部材１１、第２部材および第３部材１３のうちのいずれか（ここでは、第１部材１１）が、コンパウンド構成を有する点が上記第１の実施の形態とは異なる。 <2. Modification>
FIG. 9 is a perspective view showing a configuration of a wavelength-selective phase difference element (wavelength-selective phase difference element 10A) according to a modification of the first embodiment. Similar to the first embodiment, the wavelength-selective phase difference element 10A is used, for example, in a projection display device (for example, the projector 1) described later, and the polarization direction rotates only in a selective wavelength band. A retardation plate having such characteristics. In the wavelength-selective phase difference element 10A of the present modification, one of the bonded first member 11, second member, and third member 13 (here, the first member 11) has a compound configuration. However, this is different from the first embodiment.
　本変形例における第１部材１１は、上記のようにコンパウンド構成、即ち、２枚の板状部材（板状部材１１Ａ，１１Ｂ）から構成されたものである。板状部材１１Ａおよび板状部材１１Ｂは、上記第１の実施の形態と同様に、例えば、一軸性結晶または一軸性有機材料によって構成することができる。板状部材１１Ａおよび板状部材１１Ｂは、それぞれ面（ＸＹ平面）内に対して平行な光学軸を有し、第１部材１１を構成する際には、光学軸が互いに直交するように貼り合わされている。これにより、板状部材１１Ａと板状部材１１Ｂとで生じる位相差シフト量が互いに相殺されるようになっている。 The first member 11 in the present modification has a compound configuration as described above, that is, is composed of two plate-like members (plate- like members 11A and 11B). The plate-like member 11A and the plate-like member 11B can be made of, for example, a uniaxial crystal or a uniaxial organic material, as in the first embodiment. The plate-like member 11A and the plate-like member 11B each have an optical axis parallel to the plane (XY plane), and when the first member 11 is formed, they are bonded so that the optical axes are orthogonal to each other. ing. Thereby, the amount of phase difference shift produced by plate-like member 11A and plate-like member 11B cancels mutually.
　本変形例における波長選択性位相差素子１０Ａは、第１部材１１、第２部材１２および第３部材１３が、光入射面Ｓ１側または光出射面Ｓ２側から２：２：３の比となる関係を有するように構成されている。ここで、２：２：３の比の第１部材１１、第２に部材１２および第３部材における各値は、各部材１１，１２，１３のうち、１枚の板状部材から構成されている部材（本変形例では、第２に部材１２および第３部材）では、その板状部材の厚みに相当する。各部材１１，１２，１３のうち、２枚の板状部材から構成されている部材（本変形例では、第１部材１１）では、その板状部材の厚み差に相当する。即ち、図９に示した波長選択性位相差素子１０Ａにおける２：２：３の比は、板状部材１１Ａと板状部材１１Ｂとの厚み差（ｔ４－ｔ５の絶対値）：第２部材１２の厚み（ｔ２）：第３部材１３の厚み（ｔ３）となる。 In the wavelength-selective phase difference element 10A in this modification, the first member 11, the second member 12, and the third member 13 have a ratio of 2: 2: 3 from the light incident surface S1 side or the light emitting surface S2 side. It is configured to have a relationship. Here, each value in the first member 11 of the ratio 2: 2: 3, secondly the member 12 and the third member is composed of one plate-like member among the members 11, 12, 13. In the present member (second member 12 and third member in the present modification), this corresponds to the thickness of the plate member. Of the members 11, 12, and 13, the member composed of two plate-like members (in the present modification, the first member 11) corresponds to the thickness difference between the plate-like members. That is, the ratio of 2: 2: 3 in the wavelength selective phase difference element 10A shown in FIG. 9 is the thickness difference between the plate-like member 11A and the plate-like member 11B (absolute value of t4-t5): the second member 12 Thickness (t2): the thickness (t3) of the third member 13.
　以上のことから、板状部材１１Ａおよび板状部材１１Ｂの厚み（ｔ４，ｔ５）は、その差が所定の値となるように設計することが好ましい。一例として、例えば、第２部材１２および第３部材１３の厚みが、それぞれ２００μｍ，３００μｍである場合には、第１部材１１を構成する板状部材１１Ａおよび板状部材１１Ｂの厚みは、例えば、２００μｍ（板状部材１１Ａ），４００μｍ（板状部材１１Ｂ）となる。なお、板状部材１１Ａおよび板状部材１１Ｂの厚みは、その差が、第２部材１２の厚みに相当すればよく、板状部材１１Ａの方が厚くて形成されていてもよい。 From the above, the thickness (t4, t5) of the plate-like member 11A and the plate-like member 11B is preferably designed so that the difference becomes a predetermined value. As an example, for example, when the thicknesses of the second member 12 and the third member 13 are 200 μm and 300 μm, respectively, the thicknesses of the plate-like member 11A and the plate-like member 11B constituting the first member 11 are, for example, 200 μm (plate member 11A) and 400 μm (plate member 11B). The difference between the thicknesses of the plate-like member 11A and the plate-like member 11B only needs to correspond to the thickness of the second member 12, and the plate-like member 11A may be formed thicker.
　また、本変形例では、波長選択性位相差素子１０Ａを構成する第１部材１１、第２部材１２および第３部材１３のうち、第１部材１１がコンパウンド構成をとる例を説明したが、これに限らず、例えば、第２部材１２または第３部材１３がコンパウンド構成をとるようにしてもよい。第３部材１３がコンパウンド構成をとる場合には、第３部材１３を構成する２枚の板状部材の厚み差が、第１部材１１（または、第２部材１２）の厚みに対して１．５倍となるように構成される。また、第１部材１１、第２部材１２および第３部材１３のうちの２つの部材（第１部材１１、第２部材および第３部材１３のうちのいずれか２つ）あるいは、全ての部材（第１部材１１、第２部材および第３部材１３の全て）がコンパウンド構成をとるようにしてもよい。 Moreover, although this modification demonstrated the example in which the 1st member 11 takes a compound structure among the 1st member 11, the 2nd member 12, and the 3rd member 13 which comprise the wavelength selective phase difference element 10A, For example, the second member 12 or the third member 13 may have a compound configuration. When the third member 13 has a compound configuration, the difference in thickness between the two plate-like members constituting the third member 13 is 1.V. with respect to the thickness of the first member 11 (or the second member 12). It is configured to be 5 times. Moreover, two members (any two of the first member 11, the second member, and the third member 13) of the first member 11, the second member 12, and the third member 13 or all the members ( All of the first member 11, the second member, and the third member 13) may take a compound configuration.
＜３．第２の実施の形態＞
　図１０は、本開示の第２の実施の形態に係る波長選択性位相差素子（波長選択性位相差素子２０）の構成を斜視的に表したものである。この波長選択性位相差素子２０は、第１の実施の形態と同様に、例えば、後述する投射型表示装置（例えば、プロジェクタ１）に用いられ、選択的な波長帯域においてのみ偏光方向が回転するような特性を持つ位相差板である。本実施の形態の波長選択性位相差素子２０は、貼り合わされた第１部材１１、第２部材および第３部材１３の光入射面Ｓ１および光出射面Ｓ２に、それぞれガラス板２１，２２が貼り合わされている点が上記実施の形態とは異なる。 <3. Second Embodiment>
FIG. 10 is a perspective view of a configuration of a wavelength selective phase difference element (wavelength selective phase difference element 20) according to the second embodiment of the present disclosure. Similar to the first embodiment, the wavelength-selective phase difference element 20 is used in, for example, a projection display device (for example, the projector 1) described later, and the polarization direction rotates only in a selective wavelength band. A retardation plate having such characteristics. In the wavelength-selective phase difference element 20 of the present embodiment, glass plates 21 and 22 are attached to the light incident surface S1 and the light exit surface S2 of the first member 11, the second member, and the third member 13, respectively. They are different from the above-described embodiment.
（３－１．波長選択性位相差素子の構成）
　本実施の形態の波長選択性位相差素子２０は、上記のように、第１部材１１の光入射面Ｓ１および第３部材１３の光出射面Ｓ２に、それぞれガラス板２１，２２が貼り合わされた構成を有する。 (3-1. Configuration of wavelength selective phase difference element)
As described above, in the wavelength-selective phase difference element 20 of the present embodiment, the glass plates 21 and 22 are bonded to the light incident surface S1 of the first member 11 and the light emitting surface S2 of the third member 13, respectively. It has a configuration.
　ガラス板２１，２２は、例えば、アルミノケイ酸ガラス、石英ガラス、白板ガラス（クラウンガラス）、ホウケイ酸ガラスおよび無アルカリガラス等を用いることが好ましい。ガラス板２１，２２のＺ軸方向の厚みは、加工限度から、例えば下限が０．２ｍｍ以上となる。なお、上限については特に問わない。 The glass plates 21 and 22 are preferably made of, for example, aluminosilicate glass, quartz glass, white plate glass (crown glass), borosilicate glass, alkali-free glass, or the like. From the processing limit, the lower limit of the thickness of the glass plates 21 and 22 in the Z-axis direction is, for example, 0.2 mm or more. The upper limit is not particularly limited.
（３－２．波長選択性位相差素子の製造方法）
　本実施の形態の波長選択性位相差素子２０は、例えば、次のようにして製造することができる。 (3-2. Manufacturing method of wavelength selective phase difference element)
The wavelength selective phase difference element 20 of the present embodiment can be manufactured, for example, as follows.
　まず、面内に対して平行な光学軸を有すると共に、厚み比が２：２：３となっている第１部材１１、第２部材１２および第３部材１３を用意する。続いて、第１部材１１、第２部材１２および第３部材１３を、例えば接着剤を用いてこの順に貼り合わせる。このとき、第１部材１１、第２部材１２および第３部材１３の光学軸は、例えば上記一例（図２）として挙げた光学軸の角度となるように調整する。なお、第１部材１１、第２部材１２および第３部材１３の貼り合わせは、接着剤を用いる以外に、例えば、オプティカルコンタクト接合あるいは分子間接合を用いてもよい。 First, a first member 11, a second member 12 and a third member 13 having an optical axis parallel to the in-plane and having a thickness ratio of 2: 2: 3 are prepared. Subsequently, the first member 11, the second member 12, and the third member 13 are bonded together in this order using, for example, an adhesive. At this time, the optical axes of the first member 11, the second member 12, and the third member 13 are adjusted to be the angle of the optical axis given as an example in the above example (FIG. 2). The first member 11, the second member 12, and the third member 13 may be bonded together using, for example, optical contact bonding or intermolecular bonding, in addition to using an adhesive.
　次に、第１部材１１の光入射面Ｓ１および第３部材１３の光出射面Ｓ２のそれぞれに、例えば接着剤を用いてガラス板２１，２２を貼り合わせる。続いて、ガラス板２１，２２の表面を研磨したのち、所定の形状および大きさに切断する。以上により、図１０に示した波長選択性位相差素子２０が完成する。なお、ガラス板２１，２２の表面には、例えば、反射防止コーティング等を行ってもよい。 Next, the glass plates 21 and 22 are bonded to the light incident surface S1 of the first member 11 and the light emitting surface S2 of the third member 13 using, for example, an adhesive. Subsequently, after the surfaces of the glass plates 21 and 22 are polished, they are cut into a predetermined shape and size. Thus, the wavelength selective phase difference element 20 shown in FIG. 10 is completed. In addition, you may perform antireflection coating etc. on the surface of the glass plates 21 and 22, for example.
（３－３．作用・効果）
　上述したマルチオーダー波長板やコンパウンドゼロオーダー波長板のように、複数の部材（例えば、水晶板）によって構成されている波長選択性位相差素子では、各水晶板は、接着剤等によって貼り合わされている。このような複数の水晶板によって構成されている波長選択性位相差素子では、接着剤の厚みのばらつきによって光学的距離にばらつきが生じ、面精度および平行度が低下する虞がある。 (3-3. Action and effect)
In the wavelength selective phase difference element constituted by a plurality of members (for example, a quartz plate), such as the multi-order wave plate and the compound zero order wave plate described above, each quartz plate is bonded by an adhesive or the like. Yes. In such a wavelength-selective phase difference element composed of a plurality of quartz plates, the optical distance varies due to variations in the thickness of the adhesive, and the surface accuracy and parallelism may decrease.
　これに対して、本実施の形態の波長選択性位相差素子２０では、貼り合わされた第１部材１１、第２部材および第３部材１３をガラス板２１，２２で挟んだ、いわゆるガラスサンドイッチ構造としたので、上記第１の実施の形態における波長選択性位相差素子１０よりも面精度および平行度をさらに向上させることが可能となる。よって、上記第１の実施の形態における効果に加えて、波面収差の発生を抑制し、位相差板として、本実施の形態の波長選択性位相差素子２０を用いた投射型表示装置におけるフォーカス精度をさらに向上させることが可能となるという効果を奏する。 On the other hand, in the wavelength selective phase difference element 20 of the present embodiment, a so-called glass sandwich structure in which the bonded first member 11, second member and third member 13 are sandwiched between glass plates 21 and 22. Therefore, it is possible to further improve the surface accuracy and the parallelism as compared with the wavelength selective phase difference element 10 in the first embodiment. Therefore, in addition to the effects in the first embodiment, the occurrence of wavefront aberration is suppressed, and the focus accuracy in the projection display apparatus using the wavelength-selective phase difference element 20 of the present embodiment as the phase difference plate. It is possible to further improve the effect.
　なお、本実施の形態では、上記第１の実施の形態で示した波長選択性位相差素子１０をガラス板２１，２２で挟んだ例を示したが、これに限らない。例えば、上記変形例で示した波長選択性位相差素子１０Ａをガラス板２１，２２で挟んだ構成とすることでも、本実施の形態と同様の効果が得られる。 In the present embodiment, the example in which the wavelength selective phase difference element 10 shown in the first embodiment is sandwiched between the glass plates 21 and 22 is shown, but the present invention is not limited to this. For example, the same effect as that of the present embodiment can be obtained by adopting a configuration in which the wavelength selective phase difference element 10A shown in the above modification is sandwiched between the glass plates 21 and 22.
＜４．適用例＞
（適用例１）
　図１１は、上記第１の実施の形態（あるいは変形例および第２の実施の形態）において説明した波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）を備えた投射型表示装置（プロジェクタ１）の構成を表したものである。このプロジェクタ１は、画像信号に基づき、光源から出力された光（照明光）をＲＧＢの各色毎に変調して合成することにより画像光を生成し、例えばスクリーンに画像を投射する表示装置である。プロジェクタ１は、赤、青および緑の各色用の反射型の光変調素子４１Ｒ，４１Ｇ，４１Ｂを３枚用いてカラー画像表示を行う、いわゆる３板方式の反射型プロジェクタである。 <4. Application example>
(Application example 1)
FIG. 11 shows a projection type equipped with the wavelength-selective phase difference element 10 (or wavelength-selective phase difference elements 10A and 20) described in the first embodiment (or the modified example and the second embodiment). 2 shows a configuration of a display device (projector 1). The projector 1 is a display device that generates image light by modulating and synthesizing light (illumination light) output from a light source for each color of RGB based on an image signal, and projecting an image on a screen, for example. . The projector 1 is a so-called three-plate type reflective projector that performs color image display using three reflective light modulation elements 41R, 41G, and 41B for red, blue, and green colors.
　このプロジェクタ１は、光軸３０に沿って、光源３１と、インテグレータ３２と、ダイクロイックミラー３３（波長選択素子）とを備えている。光源３１は、カラー画像表示に必要とされる、赤色光（Ｒ）、青色光（Ｂ）および緑色光（Ｇ）を含んだ白色光を発するものであり、例えばハロゲンランプ、メタルハライドランプまたはキセノンランプ等により構成されている。また、例えば半導体レーザ（ＬＤ）または発光ダイオード（ＬＥＤ）等の固体光源を用いてもよい。更に、光源３１は、上記のように白色光を出射する１つの光源（白色光源部）に限定されず、例えば、緑色帯域の光を出射する緑色光源部、青色帯域の光を出射する青色光源部及び赤色帯域の光を出射する赤色光源部の３種の光源部から構成するようにしてもよい。インテグレータ３２は、ＰＳコンバータ等を含み、光源３１からの光の均一化や効率的な利用を図るために設けられている。ダイクロイックミラー３３は、白色光を、青色光Ｂとその他の色光（赤色光Ｒ，緑色光Ｇ）とに分離する機能を有している。 The projector 1 includes a light source 31, an integrator 32, and a dichroic mirror 33 (wavelength selection element) along the optical axis 30. The light source 31 emits white light including red light (R), blue light (B), and green light (G) required for color image display. For example, a halogen lamp, a metal halide lamp, or a xenon lamp is used. Etc. Further, a solid light source such as a semiconductor laser (LD) or a light emitting diode (LED) may be used. Furthermore, the light source 31 is not limited to one light source (white light source unit) that emits white light as described above. For example, a green light source unit that emits light in the green band and a blue light source that emits light in the blue band. You may make it comprise from three types of light source parts of a red light source part which radiate | emits a part and a red zone | band light. The integrator 32 includes a PS converter and the like, and is provided in order to make the light from the light source 31 uniform and efficiently used. The dichroic mirror 33 has a function of separating white light into blue light B and other color lights (red light R, green light G).
　プロジェクタ１は、また、ダイクロイックミラー３３によって分離された赤色光Ｒおよび緑色光Ｇの光路上において、光の進む順に、プリＰＢＳ（偏光ビームスプリッタ）３４と、集光レンズ３６と、ダイクロイックミラー３８とを備えている。プロジェクタ１は、また、ダイクロイックミラー３３によって分離された青色光Ｂの光路上において、光の進む順に、プリＰＢＳ３５と、集光レンズ３７とを備えている。プリＰＢＳ３４，３５は、入射光のうち所定偏光成分の光を選択的に反射する機能を有している。ダイクロイックミラー３８は、プリＰＢＳ３４および集光レンズ３６を経て入射された赤色光Ｒと緑色光Ｇとを分離する機能を有している。 The projector 1 also includes a pre-PBS (polarized beam splitter) 34, a condensing lens 36, and a dichroic mirror 38 in the order in which light travels on the optical path of red light R and green light G separated by the dichroic mirror 33. It has. The projector 1 also includes a pre-PBS 35 and a condenser lens 37 in the order in which light travels on the optical path of the blue light B separated by the dichroic mirror 33. The pre-PBSs 34 and 35 have a function of selectively reflecting light having a predetermined polarization component in incident light. The dichroic mirror 38 has a function of separating red light R and green light G incident through the pre-PBS 34 and the condenser lens 36.
　なお、プリＰＢＳ３４，３５は、例えば、集光レンズ３６～集光レンズ３９Ｒ，３９Ｇ，３９Ｂの間のいずれかの位置に配置するようにしてもよい。その際には、図１１に示したプリＰＢＳ３４，３５の位置には、ミラーが配置される。 The pre-PBSs 34 and 35 may be arranged at any position between the condenser lens 36 and the condenser lenses 39R, 39G, and 39B, for example. At that time, mirrors are arranged at the positions of the pre-PBSs 34 and 35 shown in FIG.
　プロジェクタ１において、赤色光Ｒ、緑色光Ｇおよび青色光Ｂの各光路上には、光の入射側から順に、集光レンズ３９Ｒ，３９Ｇ，３９Ｂと、ＰＢＳ４０Ｒ，４０Ｇ，４０Ｂと、１／４波長板４２Ｒ，４２Ｇ，４２Ｂと、光変調素子４１Ｒ，４１Ｇ，４１Ｂとが設けられている。 In projector 1, on each optical path of red light R, green light G, and blue light B, in order from the light incident side, condenser lenses 39R, 39G, 39B, PBS 40R, 40G, 40B, and 1/4 wavelength. Plates 42R, 42G, 42B and light modulation elements 41R, 41G, 41B are provided.
　光変調素子４１Ｒ，４１Ｇ，４１Ｂは、例えば反射型液晶パネルにより構成されている。反射型液晶パネルとしては、例えばＬＣＯＳ（Liquid Crystal On Silicon）等の液晶素子を用いることができる。光変調素子４１Ｒ，４１Ｇ，４１Ｂには、それぞれＰＢＳ４０Ｒ，４０Ｇ，４０Ｂの偏光選択面によって選択された所定の偏光成分（例えばＳ偏光成分）の色光が入射されるようになっている。光変調素子４１Ｒ，４１Ｇ，４１Ｂは、偏光状態の制御により入射光に変調を施し、その変調光をＰＢＳ４０Ｒ，４０Ｇ，４０Ｂに向けて反射するようになっている。 The light modulation elements 41R, 41G, 41B are constituted by, for example, a reflective liquid crystal panel. As the reflective liquid crystal panel, for example, a liquid crystal element such as LCOS (Liquid Crystal On Silicon) can be used. Color light of a predetermined polarization component (for example, S polarization component) selected by the polarization selection surfaces of the PBSs 40R, 40G, and 40B is incident on the light modulation elements 41R, 41G, and 41B, respectively. The light modulation elements 41R, 41G, and 41B modulate the incident light by controlling the polarization state, and reflect the modulated light toward the PBSs 40R, 40G, and 40B.
　ＰＢＳ４０Ｒ，４０Ｇ，４０Ｂは、それぞれ偏光選択面を有し、その偏光選択面において、光変調素子４１Ｒ，４１Ｇ，４１Ｂに入射させる所定偏光成分（Ｓ偏光成分）の光を選択（反射）すると共に、光変調素子４１Ｒ，４１Ｇ，４１Ｂによって反射された光のうち、所定偏光成分（Ｐ偏光成分）の光を、画像表示用の光として選択（透過）して出射する機能を有している。なお、図１１の例では、ＰＢＳ４０Ｒ，４０Ｇ，４０Ｂにおいて、Ｓ偏光成分の光を反射して光変調素子４１Ｒ，４１Ｇ，４１Ｂへの入射光とし、光変調素子４１Ｒ，４１Ｇ，４１Ｂからの戻り光のうち、Ｐ偏光成分の光を出射光として透過するような光学配置としてあるが、これとは逆に、Ｐ偏光の入射光を光変調素子４１Ｒ，４１Ｇ，４１Ｂの正面側から入射させ、その戻り光のうち、光変調素子４１Ｒ，４１Ｇ，４１Ｂにおいて反射により選択されたＳ偏光成分の光線を、画像表示用の光とするような配置とすることも可能である。 Each of the PBSs 40R, 40G, and 40B has a polarization selection surface, and on the polarization selection surface, selects (reflects) light of a predetermined polarization component (S polarization component) incident on the light modulation elements 41R, 41G, and 41B. Of the light reflected by the light modulation elements 41R, 41G, and 41B, the light having a predetermined polarization component (P polarization component) is selected (transmitted) as light for image display and emitted. In the example of FIG. 11, the PBSs 40R, 40G, and 40B reflect S-polarized component light to be incident on the light modulation elements 41R, 41G, and 41B, and return light from the light modulation elements 41R, 41G, and 41B. Among them, the optical arrangement is such that the light of the P-polarized component is transmitted as the outgoing light. On the contrary, incident light of the P-polarized light is incident from the front side of the light modulation elements 41R, 41G, and 41B. Of the return light, the light modulation element 41R, 41G, 41B may be arranged so that the light of the S polarization component selected by reflection is used as image display light.
　１／４波長板４２Ｒ，４２Ｇ，４２Ｂは、ＰＢＳ４０Ｒ，４０Ｇ，４０Ｂと光変調素子４１Ｒ，４１Ｇ，４１Ｂとの間で、偏光状態の補正を行うためのものであり、互いに直交する偏光成分の光に対してほぼ１／４波長の位相差を発生させるようになっている。なお、この１／４波長板も、本開示の波長選択性位相差素子で構成してもよい。 The quarter- wave plates 42R, 42G, and 42B are for correcting the polarization state between the PBSs 40R, 40G, and 40B and the light modulation elements 41R, 41G, and 41B. In contrast, a phase difference of almost ¼ wavelength is generated. In addition, you may comprise this quarter wavelength plate also with the wavelength selective phase difference element of this indication.
　プロジェクタ１は、また、クロスダイクロイックプリズム４４と、投影レンズ４５と、スクリーン４６とを備え、さらに、クロスダイクロイックプリズム４４と投影レンズ４５との間に、本開示の波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）が配置されている。なお、波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）は、クロスダイクロイックプリズム４４の出射面に接着されていてもよい。あるいは、波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）は、投影レンズ４５の入射側に機械的に接続されていてもよい。クロスダイクロイックプリズム４４は、ＰＢＳ４０Ｒ，４０Ｇ，４０Ｂによって選択された所定偏光成分の各色光を合成して出射する機能を有している。このクロスダイクロイックプリズム４４は、３つの入射面と１つの出射面とを有している。 The projector 1 also includes a cross dichroic prism 44, a projection lens 45, and a screen 46. Further, the wavelength selective phase difference element 10 (or the present disclosure) is provided between the cross dichroic prism 44 and the projection lens 45. Wavelength selective phase difference elements 10A, 20) are arranged. The wavelength-selective phase difference element 10 (or the wavelength-selective phase difference elements 10A and 20) may be bonded to the exit surface of the cross dichroic prism 44. Alternatively, the wavelength selective phase difference element 10 (or the wavelength selective phase difference elements 10 </ b> A and 20) may be mechanically connected to the incident side of the projection lens 45. The cross dichroic prism 44 has a function of combining and emitting each color light of a predetermined polarization component selected by the PBSs 40R, 40G, and 40B. The cross dichroic prism 44 has three entrance surfaces and one exit surface.
　クロスダイクロイックプリズム４４における光の入射面と、ＰＢＳ４０Ｒ，４０Ｇ，４０Ｂにおける光の出射面との間には、それらの光学素子の温度変化等による応力歪みを防止するために、スペーサ４３Ｒ，４３Ｇ，４３Ｂが設けられている。なお、スペーサ４３Ｒ，４３Ｇ，４３Ｂの位置には、偏光ビームスプリッタ（ＰＢＳ）あるいは、ダイクロイックプリズムを配置するようにしてもよい。ＰＢＳを配置することで、偏光漏れがカットされる。また、ダイクロイックプリズムを配置することで、意図しない波長の光を反射させることが可能となる。また、スペーサ４３Ｒ，４３Ｂとクロスダイクロイックプリズム４４との間には、１／２波長板４６Ｒ，４６Ｂがそれぞれ配置されている。光変調素子４１Ｒ，４１Ｂから反射された赤色光および青色光は、この１／２波長板４６Ｒ，４６Ｂを透過する際にＰ偏光成分からＳ偏光成分に変換される。 Spacers 43R, 43G, and 43B are disposed between the light incident surface of the cross dichroic prism 44 and the light output surfaces of the PBSs 40R, 40G, and 40B in order to prevent stress distortion due to temperature changes of these optical elements. Is provided. A polarization beam splitter (PBS) or a dichroic prism may be disposed at the positions of the spacers 43R, 43G, and 43B. By placing PBS, polarization leakage is cut. In addition, by arranging the dichroic prism, it is possible to reflect light having an unintended wavelength. Further, half- wave plates 46R and 46B are arranged between the spacers 43R and 43B and the cross dichroic prism 44, respectively. Red light and blue light reflected from the light modulation elements 41R and 41B are converted from P-polarized light components to S-polarized light components when passing through the half- wave plates 46R and 46B.
　投影レンズ４５は、クロスダイクロイックプリズム４４の出射面側に配置されている。この投影レンズ４５は、クロスダイクロイックプリズム４４から出射された合成光を、スクリーン４６に向けて投射する機能を有している。 The projection lens 45 is disposed on the exit surface side of the cross dichroic prism 44. The projection lens 45 has a function of projecting the combined light emitted from the cross dichroic prism 44 toward the screen 46.
　波長選択性位相差素子は、所定の波長帯域の光を選択的に偏光変換するものであり、本適用例における波長選択性位相差素子１０は、緑色帯域の光を選択的に偏光変換するように構成されたものである。プロジェクタ１では、クロスダイクロイックプリズム４４に入射される各色光の偏光成分は、赤色光および青色光はＳ偏光成分、緑色光はＰ偏光成分となっている。そこで、クロスダイクロイックプリズム４４と投影レンズ４５との間に、この波長選択性位相差素子１０を配置することで、クロスダイクロイックプリズム４４において合成された光のうち、緑色帯域の光が選択的にＳ偏光成分に変換される。 The wavelength-selective phase difference element selectively converts light in a predetermined wavelength band. The wavelength-selective phase difference element 10 in this application example selectively converts light in the green band. It is composed of. In the projector 1, the polarization components of each color light incident on the cross dichroic prism 44 are S-polarization components for red light and blue light, and P-polarization components for green light. Therefore, by arranging this wavelength-selective phase difference element 10 between the cross dichroic prism 44 and the projection lens 45, the light in the green band among the lights synthesized in the cross dichroic prism 44 is selectively S. It is converted into a polarization component.
　なお、本開示の波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）は、クロスダイクロイックプリズム４４と投影レンズ４５との間以外の場所に配置するようにしてもよい。例えば、上記１／２波長板４６Ｒ，４６Ｂを本開示の波長選択性位相差素子で構成してもよい。また、プロジェクタの構成によっては、例えば、ＰＢＳ４０Ｒ，４０Ｇ，４０Ｂとスペーサ４３Ｒ，４３Ｇ，４３Ｂとの間に、１／２波長板に相当する波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）を配置するようにしてもよい。 Note that the wavelength-selective phase difference element 10 (or the wavelength-selective phase difference elements 10A and 20) of the present disclosure may be arranged at a place other than between the cross dichroic prism 44 and the projection lens 45. For example, the half- wave plates 46R and 46B may be configured by the wavelength selective phase difference element of the present disclosure. Depending on the configuration of the projector, for example, the wavelength-selective phase difference element 10 (or the wavelength-selective phase difference element corresponding to a half-wave plate) between the PBSs 40R, 40G, and 40B and the spacers 43R, 43G, and 43B. 10A, 20) may be arranged.
（適用例２）
　図１２は、上記第１の実施の形態（あるいは変形例および第２の実施の形態）において説明した波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）を備えた投射型表示装置（プロジェクタ２）の構成を表したものである。このプロジェクタ２は、赤、青および緑の各色用の光変調素子として透過型の３枚の液晶パネル（液晶パネル部６４Ｒ，６４Ｇ，６４Ｂ）を用いてカラー画像表示を行う、いわゆる３板方式の透過型プロジェクタである。 (Application example 2)
FIG. 12 shows a projection type equipped with the wavelength-selective phase difference element 10 (or wavelength-selective phase difference elements 10A and 20) described in the first embodiment (or the modified example and the second embodiment). 2 shows a configuration of a display device (projector 2). The projector 2 is a so-called three-plate system that performs color image display using three transmissive liquid crystal panels (liquid crystal panel portions 64R, 64G, and 64B) as light modulation elements for red, blue, and green colors. It is a transmissive projector.
　プロジェクタ２は、光を発する光源５１を有している。この光源５１は、例えば白色光を発する発光体５１Ａと、発光体５１Ａから発せられた光を反射し、ほぼ平行光として出射する凹面鏡５１Ｂとを含んで構成されている。発光体５１Ａとしては、例えば、ハロゲンランプ、メタルハライドランプまたはキセノンランプ等が使用される。また、例えば半導体レーザ（ＬＤ）または発光ダイオード（ＬＥＤ）等の固体光源を用いてもよい。凹面鏡５１Ｂは、集光効率が良い形状であることが望ましく、例えば回転楕円面鏡や回転放物面鏡等の回転対称な面形状となっている。 The projector 2 has a light source 51 that emits light. The light source 51 includes, for example, a light emitter 51A that emits white light, and a concave mirror 51B that reflects the light emitted from the light emitter 51A and emits the light as substantially parallel light. For example, a halogen lamp, a metal halide lamp, or a xenon lamp is used as the light emitter 51A. Further, a solid light source such as a semiconductor laser (LD) or a light emitting diode (LED) may be used. The concave mirror 51B desirably has a shape with good light collection efficiency, and has a rotationally symmetric surface shape such as a spheroidal mirror or a parabolic mirror.
　光源５１からの出射光の進行方向に沿って、例えば、ＵＶ（紫外線）／ＩＲ（赤外線）カットフィルタ５２と、第１フライアイレンズ５３Ａと、第２フライアイレンズ５３Ｂと、ＰＳコンバータ５４と、第１集光レンズ５５とが順に配置されている。ＵＶ／ＩＲカットフィルタ５２は、光源５１から発せられた白色光に含まれる紫外領域および赤外領域の光を除去するものである。第１フライアイレンズ５３Ａおよび第２フライアイレンズ５３Ｂは、いずれも入射光を分割してそれぞれ出射する複数のレンズ要素を備えており、これにより、後述する液晶パネル部６４Ｒ，６４Ｇ，６４Ｂにおける光の強度分布を均一化するようになっている。ＰＳコンバータ５４は、光源５１から出射された光をＰ偏光成分またはＳ偏光成分に変換するものである。第１集光レンズ５５は、後述する第２集光レンズ６３Ｒ，６３Ｇ，６３Ｂと共に、光を液晶パネル部６４Ｒ，６４Ｇ，６４Ｂにそれぞれ集光させるものである。なお、第１集光レンズ５５は、光軸５０を有している。 Along the traveling direction of the light emitted from the light source 51, for example, a UV (ultraviolet) / IR (infrared) cut filter 52, a first fly-eye lens 53A, a second fly-eye lens 53B, a PS converter 54, The 1st condensing lens 55 is arrange | positioned in order. The UV / IR cut filter 52 removes light in the ultraviolet region and infrared region contained in white light emitted from the light source 51. Each of the first fly-eye lens 53A and the second fly-eye lens 53B includes a plurality of lens elements that respectively divide incident light and emit the light, whereby light in liquid crystal panel portions 64R, 64G, and 64B, which will be described later, is provided. The intensity distribution is made uniform. The PS converter 54 converts light emitted from the light source 51 into a P-polarized component or an S-polarized component. The 1st condensing lens 55 condenses light on liquid crystal panel part 64R, 64G, 64B with the 2nd condensing lens 63R, 63G, 63B mentioned later, respectively. The first condenser lens 55 has an optical axis 50.
　このプロジェクタ２では、第１集光レンズ５５からの出射光の進行方向に、ダイクロイックミラー５６が設けられている。このダイクロイックミラー５６は、第１集光レンズ５５を介して入射した光を、青色光ＬＢと、その他の色光とに分離するものである。ダイクロイックミラー５６によって分離された青色光ＬＢの光路に沿って、全反射ミラー５７と、第２集光レンズ６３Ｂと、液晶パネル部６４Ｂとが順に配置されている。全反射ミラー５７は、ダイクロイックミラー５６によって分離された青色光ＬＢを、液晶パネル部６４Ｂに向けて反射するようになっている。第２集光レンズ６３Ｂは、全反射ミラー５７によって反射された青色光ＬＢを、液晶パネル部６４Ｂに集光するようになっている。液晶パネル部６４Ｂは、全反射ミラー５７および第２集光レンズ６３Ｂを介して入射した青色光ＬＢを、画像情報に応じて空間的に変調する機能を有している。 In the projector 2, a dichroic mirror 56 is provided in the traveling direction of the light emitted from the first condenser lens 55. The dichroic mirror 56 separates light incident through the first condenser lens 55 into blue light LB and other color lights. A total reflection mirror 57, a second condenser lens 63B, and a liquid crystal panel part 64B are arranged in this order along the optical path of the blue light LB separated by the dichroic mirror 56. The total reflection mirror 57 reflects the blue light LB separated by the dichroic mirror 56 toward the liquid crystal panel unit 64B. The second condenser lens 63B condenses the blue light LB reflected by the total reflection mirror 57 on the liquid crystal panel unit 64B. The liquid crystal panel unit 64B has a function of spatially modulating the blue light LB incident through the total reflection mirror 57 and the second condenser lens 63B according to image information.
　ダイクロイックミラー５６によって分離された他の色光の光路に沿って、ダイクロイックミラー５８を備えている。ダイクロイックミラー５８は、入射した光を、緑色光ＬＧと赤色光ＬＲとに分離する機能を有している。ダイクロイックミラー５８によって分離された緑色光ＬＧの光路に沿って、第２集光レンズ６３Ｇと、液晶パネル部６４Ｇとが順に配置されている。第２集光レンズ６３Ｇは、ダイクロイックミラー５８によって分離された緑色光ＬＧを、液晶パネル部６４Ｇに集光するようになっている。液晶パネル部６４Ｇは、第２集光レンズ６３Ｇを介して入射した緑色光ＬＧを、画像情報に応じて空間的に変調する機能を有している。 A dichroic mirror 58 is provided along the optical path of other color light separated by the dichroic mirror 56. The dichroic mirror 58 has a function of separating incident light into green light LG and red light LR. A second condenser lens 63G and a liquid crystal panel portion 64G are sequentially arranged along the optical path of the green light LG separated by the dichroic mirror 58. The second condensing lens 63G condenses the green light LG separated by the dichroic mirror 58 on the liquid crystal panel unit 64G. The liquid crystal panel unit 64G has a function of spatially modulating the green light LG incident through the second condenser lens 63G according to image information.
　ダイクロイックミラー５８によって分離された赤色光ＬＲの光路に沿って、リレーレンズ５９と、全反射ミラー６０と、リレーレンズ６１と、全反射ミラー６２と、第２集光レンズ６３Ｒと、液晶パネル部６４Ｒとが順に配置されている。全反射ミラー６０は、ダイクロイックミラー５８によって分離され、リレーレンズ５９を介して入射した赤色光ＬＲを、全反射ミラー６２に向けて反射するようになっている。全反射ミラー６２は、全反射ミラー６０によって反射され、リレーレンズ６１を介して入射した赤色光ＬＲを、液晶パネル部６４Ｒに向けて反射するようになっている。液晶パネル部６４Ｒは、全反射ミラー６２によって反射され、第２集光レンズ６３Ｒを介して入射した赤色光ＬＲを、画像情報に応じて空間的に変調する機能を有している。 Along the optical path of the red light LR separated by the dichroic mirror 58, the relay lens 59, the total reflection mirror 60, the relay lens 61, the total reflection mirror 62, the second condenser lens 63R, and the liquid crystal panel portion 64R. And are arranged in order. The total reflection mirror 60 is separated by the dichroic mirror 58 and reflects the red light LR incident through the relay lens 59 toward the total reflection mirror 62. The total reflection mirror 62 reflects the red light LR reflected by the total reflection mirror 60 and incident via the relay lens 61 toward the liquid crystal panel unit 64R. The liquid crystal panel unit 64R has a function of spatially modulating the red light LR reflected by the total reflection mirror 62 and incident through the second condenser lens 63R according to image information.
　赤色光ＬＲ、緑色光ＬＧおよび青色光ＬＢの光路が交わる位置には、赤色光ＬＲ、緑色光ＬＧ，青色光ＬＢを合成する機能を有するダイクロイックプリズム６５が設けられている。ダイクロイックプリズム６５は、３つの入射面６５Ｒ，６５Ｇ，６５Ｂと、１つの出射面６５Ｔとを有している。入射面６５Ｒには、液晶パネル部６４Ｒから出射された赤色光ＬＲが入射するようになっている。入射面６５Ｇには、液晶パネル部６４Ｇから出射された緑色光ＬＧが入射するようになっている。入射面６５Ｂには、液晶パネル部６４Ｂから出射された青色光ＬＢが入射するようになっている。ダイクロイックプリズム６５は、入射面６５Ｒ，６５Ｇ，６５Ｂに入射した３つの色光を合成して出射面６５Ｔから出射する。ダイクロイックプリズム６５の出射面６５Ｔ側には、本開示の波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）およびダイクロイックプリズム６５から出射された合成光を、スクリーン６７に向けて投射する投射レンズ６６が設けられている。 A dichroic prism 65 having a function of combining the red light LR, the green light LG, and the blue light LB is provided at a position where the optical paths of the red light LR, the green light LG, and the blue light LB intersect. The dichroic prism 65 has three entrance surfaces 65R, 65G, and 65B and one exit surface 65T. The red light LR emitted from the liquid crystal panel unit 64R is incident on the incident surface 65R. The green light LG emitted from the liquid crystal panel 64G is incident on the incident surface 65G. The blue light LB emitted from the liquid crystal panel portion 64B is incident on the incident surface 65B. The dichroic prism 65 combines the three color lights incident on the incident surfaces 65R, 65G, and 65B and emits them from the emission surface 65T. On the exit surface 65T side of the dichroic prism 65, the combined light emitted from the wavelength selective phase difference element 10 (or the wavelength selective phase difference elements 10A and 20) and the dichroic prism 65 of the present disclosure is directed toward the screen 67. A projection lens 66 for projecting is provided.
　なお、波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）は、上記適用例１と同様に、ダイクロイックプリズム６５の出射面に接着されていてもよい。あるいは、波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）は、投射レンズ６６の入射側に機械的に接続されていてもよい。 The wavelength-selective phase difference element 10 (or the wavelength-selective phase difference elements 10A and 20) may be bonded to the emission surface of the dichroic prism 65, as in the first application example. Alternatively, the wavelength selective phase difference element 10 (or the wavelength selective phase difference elements 10A and 20) may be mechanically connected to the incident side of the projection lens 66.
　また、本適用例における波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）は、上記適用例１と同様に、ダイクロイックプリズム６５と投射レンズ６６との間以外の場所に配置するようにしてもよい。例えば、液晶パネル部６４Ｒ，６４Ｇ，６４Ｂとダイクロイックプリズム６５との間に配置するようにしてもよい。 Further, the wavelength-selective phase difference element 10 (or the wavelength-selective phase difference elements 10A and 20) in this application example is disposed at a place other than between the dichroic prism 65 and the projection lens 66, as in the first application example. You may make it do. For example, it may be arranged between the liquid crystal panel portions 64R, 64G, and 64B and the dichroic prism 65.
（適用例３）
　図１３は、上記第１の実施の形態（あるいは変形例および第２の実施の形態）において説明した波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）を備えた投射型表示装置（プロジェクタ３）の構成を表したものである。このプロジェクタ３は、赤、青および緑の各色用の反射型の光変調素子７５Ｒ，７５Ｇ，７５Ｂを３枚用いてカラー画像表示を行う、いわゆる３板方式の反射型プロジェクタである。 (Application example 3)
FIG. 13 shows a projection type equipped with the wavelength-selective phase difference element 10 (or wavelength-selective phase difference elements 10A and 20) described in the first embodiment (or the modified example and the second embodiment). 2 shows a configuration of a display device (projector 3). The projector 3 is a so-called three-plate type reflective projector that performs color image display using three reflective light modulation elements 75R, 75G, and 75B for red, blue, and green.
　プロジェクタ３の構成を表したものである。プロジェクタ３は、例えば、光源装置（図示せず）と、色分離プリズム７１と、偏光ビームスプリッタ７２Ｇ，７２ＲＢ，７８と、波長選択性位相差素子７３Ｒ，７６Ｒと、光変調素子７５Ｇ，７５Ｂ，７５Ｒと、位相差板７７と、本開示の波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）と、投影光学系７９とを有している。このプロジェクタ３では、光源装置から出射された全ての光Ｌｒ．Ｌｇ，Ｌｂが、光入射面Ｓ１に入射するように構成されている。 This shows the configuration of the projector 3. The projector 3 includes, for example, a light source device (not shown), a color separation prism 71, polarization beam splitters 72G, 72RB, 78, wavelength selective phase difference elements 73R, 76R, and light modulation elements 75G, 75B, 75R. A phase difference plate 77, a wavelength selective phase difference element 10 (or wavelength selective phase difference elements 10A and 20) of the present disclosure, and a projection optical system 79. In the projector 3, all the light Lr. Lg and Lb are configured to enter the light incident surface S1.
　光源装置は、カラー画像表示に必要とされる、赤色光（Ｒ）、青色光（Ｂ）および緑色光（Ｇ）を含んだ白色光を発するものであり、例えばハロゲンランプ、メタルハライドランプまたはキセノンランプ等を含んで構成されている。また、例えば半導体レーザ（ＬＤ）または発光ダイオード（ＬＥＤ）等の固体光源を用いてもよい。 The light source device emits white light including red light (R), blue light (B), and green light (G) required for color image display. For example, a halogen lamp, a metal halide lamp, or a xenon lamp Etc. are configured. Further, a solid light source such as a semiconductor laser (LD) or a light emitting diode (LED) may be used.
　色分離プリズム７１は、ある波長帯域の光を透過させ、残りの波長帯域の光を反射させる光学機能膜７１ａ（光学面）と、この光学機能膜７１ａを挟んで貼り合わせられたプリズムとを含んで構成されている。この色分離プリズム７１は、例えば光入射面Ｓ１を有し、この光入射面Ｓ１に、光軸Ｚ１に沿って、例えば３つの波長帯域の光が入射するように配置されている。具体的には、具体的には、光入射面Ｓ１には、赤色帯域、緑色帯域および青色帯域の光（Ｌｒ．Ｌｇ，Ｌｂ）が入射する。なお、これら３つの波長帯域の光は、いずれか１つまたは２つの波長帯域の光が、光入射面Ｓ１とは異なる面から入射するようにしてもよい。この色分離プリズム７１の出射光（光学機能膜７１ａを透過した光および光学機能膜７１ａにおいて反射された光）の光路上に、偏光ビームスプリッタ７２Ｇおよび偏光ビームスプリッタＲＢが配置されている。 The color separation prism 71 includes an optical function film 71a (optical surface) that transmits light in a certain wavelength band and reflects light in the remaining wavelength band, and a prism that is bonded to the optical function film 71a. It consists of The color separation prism 71 has, for example, a light incident surface S1, and is arranged so that light of, for example, three wavelength bands enters the light incident surface S1 along the optical axis Z1. Specifically, light (Lr.Lg, Lb) in the red band, the green band, and the blue band is incident on the light incident surface S1. The light in these three wavelength bands may be such that light in any one or two wavelength bands is incident from a surface different from the light incident surface S1. A polarization beam splitter 72G and a polarization beam splitter RB are disposed on the optical path of the light emitted from the color separation prism 71 (the light transmitted through the optical function film 71a and the light reflected by the optical function film 71a).
　偏光ビームスプリッタ７２Ｇ，７２ＲＢは、例えば３原色のそれぞれの波長帯域の光を、対応する光変調素子７５Ｇ，７５Ｒ，７５Ｂへ導くと共に、変調後の各波長帯域の光を偏光ビームスプリッタ７８へ向けて導くものである。 The polarization beam splitters 72G and 72RB, for example, guide light in the respective wavelength bands of the three primary colors to the corresponding light modulation elements 75G, 75R, and 75B, and direct the modulated light in each wavelength band toward the polarization beam splitter 78. It is a guide.
　偏光ビームスプリッタ７２Ｇは、例えば緑色帯域の光を光変調素子７５Ｇへ導くと共に、光変調素子７５Ｇにおいて変調された後の緑色帯域の光を偏光ビームスプリッタ７８へ向けて出射するように構成されている。この偏光ビームスプリッタ７２Ｇと偏光ビームスプリッタ７８との間の光路上には、位相差板７７が配置されている。 For example, the polarization beam splitter 72G is configured to guide light in the green band to the light modulation element 75G and to emit light in the green band after being modulated by the light modulation element 75G toward the polarization beam splitter 78. . A retardation plate 77 is disposed on the optical path between the polarizing beam splitter 72G and the polarizing beam splitter 78.
　位相差板７７は、入射光の偏光方向を回転させる素子であり、ここでは、偏光方向を９０度回転させる、１／２波長板から構成されている。なお、この１／２波長板を、本開示の波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）で構成してもよい。 The phase difference plate 77 is an element that rotates the polarization direction of incident light, and here, it is composed of a half-wave plate that rotates the polarization direction by 90 degrees. In addition, you may comprise this 1/2 wavelength plate with the wavelength selective phase difference element 10 (or wavelength selective phase difference element 10A, 20) of this indication.
　偏光ビームスプリッタ７２ＲＢは、例えば赤色帯域の光を光変調素子７５Ｒへ、青色帯域の光を光変調素子７５Ｂへそれぞれ導くと共に、変調後の赤色帯域および青色帯域の各光を偏光ビームスプリッタ７８へ向けて導くものである。色分離プリズム７１と偏光ビームスプリッタ７２ＲＢとの間の光路上には、波長選択性位相差素子７３Ｒが配置されている。偏光ビームスプリッタ７２ＲＢと偏光ビームスプリッタ７８との間には、波長選択性位相差素子７６Ｒが配置されている。 For example, the polarization beam splitter 72RB guides the red band light to the light modulation element 75R, the blue band light to the light modulation element 75B, and directs each modulated red band and blue band light to the polarization beam splitter 78. To guide. A wavelength-selective phase difference element 73R is disposed on the optical path between the color separation prism 71 and the polarization beam splitter 72RB. A wavelength selective phase difference element 76R is disposed between the polarization beam splitter 72RB and the polarization beam splitter 78.
　波長選択性位相差素子７３Ｒは、選択的な波長帯域においてのみ偏光方向が回転するような特性をもつ位相差板である。この波長選択性位相差素子７３Ｒとしては、例えば、本開示の波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）を用いることができる。この波長選択性位相差素子７３Ｒでは、赤色帯域および青色帯域のうちの赤色帯域の光の偏光方向を選択的に回転させるように構成されている（青色帯域の光は偏光方向を維持したまま透過するように構成されている）。この波長選択性位相差素子７３Ｒでは、少なくとも２波長（ここでは赤色と青色）の帯域における性能のみを考慮して設計されればよく、ＲＧＢの全ての波長が考慮される必要はない（緑色帯域についての特性は任意である）。 The wavelength-selective phase difference element 73R is a phase difference plate having such a characteristic that the polarization direction rotates only in a selective wavelength band. As the wavelength selective phase difference element 73R, for example, the wavelength selective phase difference element 10 (or the wavelength selective phase difference elements 10A and 20) of the present disclosure can be used. The wavelength-selective phase difference element 73R is configured to selectively rotate the polarization direction of light in the red band out of the red band and the blue band (light in the blue band is transmitted while maintaining the polarization direction). To be configured). The wavelength-selective phase difference element 73R may be designed considering only the performance in at least two wavelengths (here, red and blue), and it is not necessary to consider all the RGB wavelengths (green band). The characteristics are arbitrary).
　波長選択性位相差素子７６Ｒは、選択的な波長帯域においてのみ偏光方向が回転するような特性をもつ位相差板である。この波長選択性位相差素子７６Ｒは、波長選択性位相差素子７３Ｒと同様に、本開示の波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）を用いることができる。この波長選択性位相差素子７６Ｒでは、赤色帯域および青色帯域のうちの赤色帯域の光の偏光方向を選択的に回転させるように構成されている（青色帯域の光は偏光方向を維持したまま透過するように構成されている）。この波長選択性位相差素子７６Ｒにおいても、上記の波長選択性位相差素子７３Ｒと同様、少なくとも２波長（ここでは赤色と青色）の帯域における性能のみを考慮して設計されればよく、ＲＧＢの全ての波長が考慮される必要はない。 The wavelength-selective phase difference element 76R is a phase difference plate having such a characteristic that the polarization direction rotates only in a selective wavelength band. As the wavelength-selective phase difference element 76R, the wavelength-selective phase difference element 10 (or the wavelength-selective phase difference elements 10A and 20) of the present disclosure can be used similarly to the wavelength-selective phase difference element 73R. The wavelength-selective phase difference element 76R is configured to selectively rotate the polarization direction of the red band light in the red band and the blue band (the blue band light is transmitted while maintaining the polarization direction). To be configured). Similarly to the wavelength selective phase difference element 73R, the wavelength selective phase difference element 76R may be designed considering only performance in a band of at least two wavelengths (here, red and blue). Not all wavelengths need to be considered.
　偏光ビームスプリッタ７８は、光変調素子７５Ｒ，７５Ｇ，７５Ｂから出射された各波長帯域の光を、合成（色合成）して投影光学系７９へ導くための素子である。光変調素子７５Ｇから出射した光は偏光ビームスプリッタ７２Ｇおよび位相差板７７を介して、光変調素子７５Ｒ，７５Ｂから出射した光は、偏光ビームスプリッタ７２ＲＢおよび波長選択性位相差素子７６Ｒを介して、それぞれ互いに異なる方向から偏光ビームスプリッタ７８に入射するように構成されている。 The polarization beam splitter 78 is an element for synthesizing (color synthesizing) the light of each wavelength band emitted from the light modulation elements 75R, 75G, and 75B and guiding it to the projection optical system 79. The light emitted from the light modulation element 75G passes through the polarization beam splitter 72G and the phase difference plate 77, and the light emitted from the light modulation elements 75R and 75B passes through the polarization beam splitter 72RB and the wavelength selective phase difference element 76R. Each is configured to enter the polarization beam splitter 78 from different directions.
　偏光ビームスプリッタ７８と投影光学系７９との間には、本開示の波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）が配置されている。この波長選択性位相差素子１０は、偏光ビームスプリッタ７８によって合成された光のうち、緑色帯域の光を選択的に偏光変換（ここでは、Ｓ偏光成分からＰ偏光成分に変換）するように構成されたものである。投影光学系７９は、偏光ビームスプリッタ７８から波長選択性位相差素子１０を介して入射された光をスクリーン上に投射して結像させるためのレンズ群等を含むものである。 Between the polarization beam splitter 78 and the projection optical system 79, the wavelength selective phase difference element 10 (or the wavelength selective phase difference elements 10A and 20) of the present disclosure is disposed. The wavelength-selective phase difference element 10 is configured to selectively convert the light in the green band from the light combined by the polarization beam splitter 78 (in this case, from S-polarized component to P-polarized component). It has been done. The projection optical system 79 includes a lens group for projecting light incident from the polarization beam splitter 78 via the wavelength selective phase difference element 10 onto a screen to form an image.
　なお、波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）は、上記適用例１，２と同様に、偏光ビームスプリッタ７８の出射面に接着されていてもよい。あるいは、波長選択性位相差素子１０（あるいは波長選択性位相差素子１０Ａ，２０）は、投影光学系７９の入射側に機械的に接続されていてもよい。 The wavelength-selective phase difference element 10 (or the wavelength-selective phase difference elements 10A and 20) may be bonded to the exit surface of the polarization beam splitter 78, as in the first and second application examples. Alternatively, the wavelength selective phase difference element 10 (or the wavelength selective phase difference elements 10A and 20) may be mechanically connected to the incident side of the projection optical system 79.
　なお、上記投射型表示装置（プロジェクタ１～３）の構成は一例であり、本開示の投射型表示装置は、このような構成に限定されるものではない。 Note that the configuration of the projection display devices (projectors 1 to 3) is merely an example, and the projection display device of the present disclosure is not limited to such a configuration.
　以上、第１，第２の実施の形態および変形例ならびに適用例を挙げて説明したが、本開示は上記実施の形態等に限定されるものではなく、種々変形が可能である。例えば、上記適用例において例示したプロジェクタ１～３における構成要素、配置および数等は、あくまでも一例であり、全ての構成要素を備える必要はなく、また、他の構成要素を更に備えていてもよい。 The first and second embodiments, modifications, and application examples have been described above, but the present disclosure is not limited to the above-described embodiments and the like, and various modifications can be made. For example, the components, arrangement, number, and the like in the projectors 1 to 3 exemplified in the application example are merely examples, and it is not necessary to include all the components, and other components may be further included. .
　また、上記実施の形態等では、複数の波長帯域として、赤色帯域、緑色帯域および青色帯域を例示したが、これらのうち一部が他の波長帯域であってもよい。また、３つの波長帯域に限らず、更に別の波長帯域として他の波長帯域、例えば近赤外帯域の光が用いられても構わない。 In the above-described embodiment and the like, the red band, the green band, and the blue band are exemplified as the plurality of wavelength bands, but some of these may be other wavelength bands. Further, the light is not limited to the three wavelength bands, and other wavelength bands, for example, light in the near infrared band may be used as another wavelength band.
　更に、第１，第２の実施の形態および変形例で説明した波長選択性位相差素子１０，１０Ａ，２０は、立体画像表示装置にも適用することが可能である。 Furthermore, the wavelength-selective phase difference elements 10, 10A, 20 described in the first and second embodiments and modifications can be applied to a stereoscopic image display apparatus.
　なお、本明細書中に記載された効果は、あくまで例示である。本開示の効果は、本明細書中に記載された効果に限定されるものではない。本開示が、本明細書中に記載された効果以外の効果を持っていてもよい。 Note that the effects described in the present specification are merely examples. The effects of the present disclosure are not limited to the effects described in this specification. The present disclosure may have effects other than those described in this specification.
　また、本開示は以下のような構成を取り得るものである。
（１）
　光入射面および光出射面と、
　前記光入射面と前記光出射面との間に順に貼り合わされた第１部材、第２部材および第３部材とを有し、
　前記第１部材、前記第２部材および前記第３部材は、その厚み比が前記光入射面の側または前記光出射面の側から２：２：３となっている
　波長選択性位相差素子。
（２）
　前記第１部材、前記第２部材および前記第３部材は、互いに異なる光学軸を有する、前記（１）に記載の波長選択性位相差素子。
（３）
　前記第１部材、前記第２部材および前記第３部材は、位相差材料によって構成されている、前記（１）または（２）に記載の波長選択性位相差素子。
（４）
　前記位相差材料は、一軸性結晶または一軸性有機材料である、前記（３）に記載の波長選択性位相差素子。
（５）
　前記第１部材の前記光入射面の側および前記第３部材の前記光出射面の側には、それぞれガラス板が貼り合わされている、前記（１）乃至（４）のうちのいずれかに記載の波長選択性位相差素子。
（６）
　光入射面および光出射面と、
　前記光入射面と前記光出射面との間に順に貼り合わされると共に、前記光入射面の側または前記光出射面の側から２：２：３の比となる関係を有する第１部材、第２部材および第３部材とを有し、
　前記第１部材、前記第２部材および前記第３部材は、少なくとも１つが２枚の板状部材からなり、
　前記比の前記第１部材、前記第２部材および前記第３部材における各値は、それぞれが、１枚の板状部材からなる場合にはその厚みに相当し、２枚の板状部材からなる場合にはその厚み差に相当する
　波長選択性位相差素子。
（７）
　前記第１部材、前記第２部材および前記第３部材のいずれかを構成する前記２枚の板状部材は、互いに直交する光学軸を有する、前記（６）に記載の波長選択性位相差素子。
（８）
　互いに異なる複数の波長帯域の光を出射する１または複数の光源部と、
　前記光源部から出射された光のうち、所定波長成分の光を透過または反射する波長選択素子と、
　前記複数の波長帯域の光をそれぞれ変調する複数の光変調素子と、
　前記複数の変調素子から出射された各波長帯域の光を合成する色合成素子と、
　前記色合成素子から出射された光を投射する投影光学系と、
　前記波長選択素子の光出射側に配置された波長選択性位相差素子とを備え、
　前記波長選択性位相差素子は、
　光入射面および光出射面と、
　前記光入射面と前記光出射面との間に順に貼り合わされた第１部材、第２部材および第３部材とを有し、
　前記第１部材、前記第２部材および前記第３部材は、その厚み比が前記光入射面の側または前記光出射面の側から２：２：３となっている
　投射型表示装置。
（９）
　前記波長選択性位相差素子は、隣り合う前記波長選択素子、前記光変調素子、前記色合成素子および前記投影光学系のいずれかの間に配置されている、前記（８）に記載の投射型表示装置。
（１０）
　前記波長選択性位相差素子は、前記複数の波長帯域のうちの所定の波長帯域の光を選択的に偏光変換する、前記（８）または（９）に記載の投射型表示装置。
（１１）
　前記複数の波長帯域は、緑色帯域、青色帯域および赤色帯域である、前記（８）乃至（１０）のうちのいずれかに記載の投射型表示装置。
（１２）
　前記１の光源部は、白色光を出射する白色光源部である、前記（８）乃至（１１）のうちのいずれかに記載の投射型表示装置。
（１３）
　前記複数の光源部は、緑色帯域の光を出射する緑色光源部と、青色帯域の光を出射する青色光源部と、赤色帯域の光を出射する赤色光源部とを有する、前記（８）乃至（１１）のうちのいずれかに記載の投射型表示装置。
（１４）
　前記色合成素子は、偏光ビームスプリッタ、ダイクロイックプリズムまたはダイクロイックミラーである、前記（８）乃至（１３）のうちのいずれかに記載の投射型表示装置。
（１５）
　互いに異なる複数の波長帯域の光を出射する１または複数の光源部と、
　前記光源部から出射された光のうち、所定波長成分の光を透過または反射する波長選択素子と、
　前記複数の波長帯域の光をそれぞれ変調する複数の光変調素子と、
　前記複数の変調素子から出射された各波長帯域の光を合成する色合成素子と、
　前記色合成素子から出射された光を投射する投影光学系と、
　前記波長選択素子の光出射側に配置された波長選択性位相差素子とを備え、
　前記波長選択性位相差素子は、
　光入射面および光出射面と、
　前記光入射面と前記光出射面との間に順に貼り合わされると共に、前記光入射面の側または前記光出射面の側から２：２：３の比となる関係を有する第１部材、第２部材および第３部材とを有し、
　前記第１部材、前記第２部材および前記第３部材は、少なくとも１つが２枚の板状部材からなり、
　前記比の前記第１部材、前記第２部材および前記第３部材における各値は、それぞれが、１枚の板状部材からなる場合にはその厚みに相当し、２枚の板状部材からなる場合にはその厚み差に相当する
　投射型表示装置。 Moreover, this indication can take the following structures.
(1)
A light incident surface and a light exit surface;
A first member, a second member, and a third member, which are sequentially bonded between the light incident surface and the light emitting surface;
The wavelength selective phase difference element in which the thickness ratio of the first member, the second member, and the third member is 2: 2: 3 from the light incident surface side or the light emitting surface side.
(2)
The wavelength selective phase difference element according to (1), wherein the first member, the second member, and the third member have different optical axes.
(3)
The wavelength selective phase difference element according to (1) or (2), wherein the first member, the second member, and the third member are made of a phase difference material.
(4)
The wavelength selective phase difference element according to (3), wherein the retardation material is a uniaxial crystal or a uniaxial organic material.
(5)
The glass plate is bonded to each of the light incident surface side of the first member and the light emission surface side of the third member, according to any one of (1) to (4). Wavelength selective phase difference element.
(6)
A light incident surface and a light exit surface;
A first member having a relationship of being in a ratio of 2: 2: 3 from the light incident surface side or the light output surface side, which is sequentially bonded between the light incident surface and the light output surface; Two members and a third member,
At least one of the first member, the second member, and the third member is composed of two plate-like members,
Each value in the ratio of the first member, the second member, and the third member corresponds to the thickness of each plate member, and includes two plate members. In some cases, a wavelength selective phase difference element corresponding to the thickness difference.
(7)
The wavelength-selective phase difference element according to (6), wherein the two plate-like members constituting any of the first member, the second member, and the third member have optical axes orthogonal to each other. .
(8)
One or a plurality of light source units that emit light of a plurality of different wavelength bands;
Of the light emitted from the light source unit, a wavelength selection element that transmits or reflects light of a predetermined wavelength component;
A plurality of light modulation elements that respectively modulate light of the plurality of wavelength bands;
A color synthesizing element that synthesizes light of each wavelength band emitted from the plurality of modulation elements;
A projection optical system for projecting light emitted from the color synthesis element;
A wavelength selective phase difference element disposed on the light emitting side of the wavelength selective element;
The wavelength selective phase difference element is:
A light incident surface and a light exit surface;
A first member, a second member, and a third member, which are sequentially bonded between the light incident surface and the light emitting surface;
The projection display device, wherein the first member, the second member, and the third member have a thickness ratio of 2: 2: 3 from the light incident surface side or the light emitting surface side.
(9)
The projection type according to (8), wherein the wavelength selective phase difference element is disposed between any of the adjacent wavelength selection element, the light modulation element, the color synthesis element, and the projection optical system. Display device.
(10)
The projection display device according to (8) or (9), wherein the wavelength-selective phase difference element selectively converts light in a predetermined wavelength band among the plurality of wavelength bands.
(11)
The projection display device according to any one of (8) to (10), wherein the plurality of wavelength bands are a green band, a blue band, and a red band.
(12)
Said 1 light source part is a projection type display apparatus in any one of said (8) thru | or (11) which is a white light source part which radiate | emits white light.
(13)
The plurality of light source units include a green light source unit that emits green band light, a blue light source unit that emits blue band light, and a red light source unit that emits red band light. The projection display device according to any one of (11).
(14)
The projection display device according to any one of (8) to (13), wherein the color composition element is a polarization beam splitter, a dichroic prism, or a dichroic mirror.
(15)
One or a plurality of light source units that emit light of a plurality of different wavelength bands;
Of the light emitted from the light source unit, a wavelength selection element that transmits or reflects light of a predetermined wavelength component;
A plurality of light modulation elements that respectively modulate light of the plurality of wavelength bands;
A color synthesizing element that synthesizes light of each wavelength band emitted from the plurality of modulation elements;
A projection optical system for projecting light emitted from the color synthesis element;
A wavelength selective phase difference element disposed on the light emitting side of the wavelength selective element;
The wavelength selective phase difference element is:
A light incident surface and a light exit surface;
A first member having a relationship of being in a ratio of 2: 2: 3 from the light incident surface side or the light output surface side, which is sequentially bonded between the light incident surface and the light output surface; Two members and a third member,
At least one of the first member, the second member, and the third member is composed of two plate-like members,
Each value in the ratio of the first member, the second member, and the third member corresponds to the thickness of each plate member, and includes two plate members. In the case, a projection type display device corresponding to the thickness difference.
　本出願は、日本国特許庁において２０１６年８月１０日に出願された日本特許出願番号２０１６－１５７５０６号を基礎として優先権を主張するものであり、この出願の全ての内容を参照によって本出願に援用する。 This application claims priority on the basis of Japanese Patent Application No. 2016-157506 filed on August 10, 2016 at the Japan Patent Office. The entire contents of this application are hereby incorporated by reference. Incorporated into.
　当業者であれば、設計上の要件や他の要因に応じて、種々の修正、コンビネーション、サブコンビネーション、および変更を想到し得るが、それらは添付の請求の範囲やその均等物の範囲に含まれるものであることが理解される。 Those skilled in the art will envision various modifications, combinations, subcombinations, and changes, depending on design requirements and other factors, which are within the scope of the appended claims and their equivalents. It is understood that

Claims (15)

  1. 　光入射面および光出射面と、
    　前記光入射面と前記光出射面との間に順に貼り合わされた第１部材、第２部材および第３部材とを有し、
    　前記第１部材、前記第２部材および前記第３部材は、その厚み比が前記光入射面の側または前記光出射面の側から２：２：３となっている
    　波長選択性位相差素子。     A light incident surface and a light exit surface;
    A first member, a second member, and a third member, which are sequentially bonded between the light incident surface and the light emitting surface;
    The wavelength selective phase difference element in which the thickness ratio of the first member, the second member, and the third member is 2: 2: 3 from the light incident surface side or the light emitting surface side.
  2. 　前記第１部材、前記第２部材および前記第３部材は、互いに異なる光学軸を有する、請求項１に記載の波長選択性位相差素子。 The wavelength-selective phase difference element according to claim 1, wherein the first member, the second member, and the third member have different optical axes.
  3. 　前記第１部材、前記第２部材および前記第３部材は、位相差材料によって構成されている、請求項１に記載の波長選択性位相差素子。 The wavelength-selective phase difference element according to claim 1, wherein the first member, the second member, and the third member are made of a phase difference material.
  4. 　前記位相差材料は、一軸性結晶または一軸性有機材料である、請求項３に記載の波長選択性位相差素子。 The wavelength selective phase difference element according to claim 3, wherein the phase difference material is a uniaxial crystal or a uniaxial organic material.
  5. 　前記第１部材の前記光入射面の側および前記第３部材の前記光出射面の側には、それぞれガラス板が貼り合わされている、請求項１に記載の波長選択性位相差素子。 The wavelength selective phase difference element according to claim 1, wherein a glass plate is bonded to each of the light incident surface side of the first member and the light emission surface side of the third member.
  6. 　光入射面および光出射面と、
    　前記光入射面と前記光出射面との間に順に貼り合わされると共に、前記光入射面の側または前記光出射面の側から２：２：３の比となる関係を有する第１部材、第２部材および第３部材とを有し、
    　前記第１部材、前記第２部材および前記第３部材は、少なくとも１つが２枚の板状部材からなり、
    　前記比の前記第１部材、前記第２部材および前記第３部材における各値は、それぞれが、１枚の板状部材からなる場合にはその厚みに相当し、２枚の板状部材からなる場合にはその厚み差に相当する
    　波長選択性位相差素子。     A light incident surface and a light exit surface;
    A first member having a relationship of being in a ratio of 2: 2: 3 from the light incident surface side or the light output surface side, which is sequentially bonded between the light incident surface and the light output surface; Two members and a third member,
    At least one of the first member, the second member, and the third member is composed of two plate-like members,
    Each value in the ratio of the first member, the second member, and the third member corresponds to the thickness of each plate member, and includes two plate members. In some cases, a wavelength selective phase difference element corresponding to the thickness difference.
  7. 　前記第１部材、前記第２部材および前記第３部材のいずれかを構成する前記２枚の板状部材は、互いに直交する光学軸を有する、請求項６に記載の波長選択性位相差素子。 The wavelength-selective phase difference element according to claim 6, wherein the two plate-like members constituting any of the first member, the second member, and the third member have optical axes orthogonal to each other.
  8. 　互いに異なる複数の波長帯域の光を出射する１または複数の光源部と、
    　前記光源部から出射された光のうち、所定波長成分の光を透過または反射する波長選択素子と、
    　前記複数の波長帯域の光をそれぞれ変調する複数の光変調素子と、
    　前記複数の変調素子から出射された各波長帯域の光を合成する色合成素子と、
    　前記色合成素子から出射された光を投射する投影光学系と、
    　前記波長選択素子の光出射側に配置された波長選択性位相差素子とを備え、
    　前記波長選択性位相差素子は、
    　光入射面および光出射面と、
    　前記光入射面と前記光出射面との間に順に貼り合わされた第１部材、第２部材および第３部材とを有し、
    　前記第１部材、前記第２部材および前記第３部材は、その厚み比が前記光入射面の側または前記光出射面の側から２：２：３となっている
    　投射型表示装置。     One or a plurality of light source units that emit light of a plurality of different wavelength bands;
    Of the light emitted from the light source unit, a wavelength selection element that transmits or reflects light of a predetermined wavelength component;
    A plurality of light modulation elements that respectively modulate light of the plurality of wavelength bands;
    A color synthesizing element that synthesizes light of each wavelength band emitted from the plurality of modulation elements;
    A projection optical system for projecting light emitted from the color synthesis element;
    A wavelength selective phase difference element disposed on the light emitting side of the wavelength selective element;
    The wavelength selective phase difference element is:
    A light incident surface and a light exit surface;
    A first member, a second member, and a third member, which are sequentially bonded between the light incident surface and the light emitting surface;
    The projection display device, wherein the first member, the second member, and the third member have a thickness ratio of 2: 2: 3 from the light incident surface side or the light emitting surface side.
  9. 　前記波長選択性位相差素子は、隣り合う前記波長選択素子、前記光変調素子、前記色合成素子および前記投影光学系のいずれかの間に配置されている、請求項８に記載の投射型表示装置。 The projection display according to claim 8, wherein the wavelength selective phase difference element is disposed between any one of the adjacent wavelength selection element, the light modulation element, the color synthesis element, and the projection optical system. apparatus.
  10. 　前記波長選択性位相差素子は、前記複数の波長帯域のうちの所定の波長帯域の光を選択的に偏光変換する、請求項８に記載の投射型表示装置。 The projection display device according to claim 8, wherein the wavelength-selective phase difference element selectively converts light in a predetermined wavelength band among the plurality of wavelength bands.
  11. 　前記複数の波長帯域は、緑色帯域、青色帯域および赤色帯域である、請求項８に記載の投射型表示装置。 The projection display device according to claim 8, wherein the plurality of wavelength bands are a green band, a blue band, and a red band.
  12. 　前記１の光源部は、白色光を出射する白色光源部である、請求項８に記載の投射型表示装置。 The projection display device according to claim 8, wherein the first light source unit is a white light source unit that emits white light.
  13. 　前記複数の光源部は、緑色帯域の光を出射する緑色光源部と、青色帯域の光を出射する青色光源部と、赤色帯域の光を出射する赤色光源部とを有する、請求項８に記載の投射型表示装置。 The plurality of light source units include a green light source unit that emits green band light, a blue light source unit that emits blue band light, and a red light source unit that emits red band light. Projection type display device.
  14. 　前記色合成素子は、偏光ビームスプリッタ、ダイクロイックプリズムまたはダイクロイックミラーである、請求項８に記載の投射型表示装置。 The projection display device according to claim 8, wherein the color composition element is a polarization beam splitter, a dichroic prism, or a dichroic mirror.
  15. 　互いに異なる複数の波長帯域の光を出射する１または複数の光源部と、
    　前記光源部から出射された光のうち、所定波長成分の光を透過または反射する波長選択素子と、
    　前記複数の波長帯域の光をそれぞれ変調する複数の光変調素子と、
    　前記複数の変調素子から出射された各波長帯域の光を合成する色合成素子と、
    　前記色合成素子から出射された光を投射する投影光学系と、
    　前記波長選択素子の光出射側に配置された波長選択性位相差素子とを備え、
    　前記波長選択性位相差素子は、
    　光入射面および光出射面と、
    　前記光入射面と前記光出射面との間に順に貼り合わされると共に、前記光入射面の側または前記光出射面の側から２：２：３の比となる関係を有する第１部材、第２部材および第３部材とを有し、
    　前記第１部材、前記第２部材および前記第３部材は、少なくとも１つが２枚の板状部材からなり、
    　前記比の前記第１部材、前記第２部材および前記第３部材における各値は、それぞれが、１枚の板状部材からなる場合にはその厚みに相当し、２枚の板状部材からなる場合にはその厚み差に相当する
    　投射型表示装置。     One or a plurality of light source units that emit light of a plurality of different wavelength bands;
    Of the light emitted from the light source unit, a wavelength selection element that transmits or reflects light of a predetermined wavelength component;
    A plurality of light modulation elements that respectively modulate light of the plurality of wavelength bands;
    A color synthesizing element that synthesizes light of each wavelength band emitted from the plurality of modulation elements;
    A projection optical system for projecting light emitted from the color synthesis element;
    A wavelength selective phase difference element disposed on the light emitting side of the wavelength selective element;
    The wavelength selective phase difference element is:
    A light incident surface and a light exit surface;
    A first member having a relationship of being in a ratio of 2: 2: 3 from the light incident surface side or the light output surface side, which is sequentially bonded between the light incident surface and the light output surface; Two members and a third member,
    At least one of the first member, the second member, and the third member is composed of two plate-like members,
    Each value in the ratio of the first member, the second member, and the third member corresponds to the thickness of each plate member, and includes two plate members. In the case, a projection type display device corresponding to the thickness difference.
PCT/JP2017/022460 2016-08-10 2017-06-19 Wavelength-selective retardation element and projection display device WO2018029987A1 (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004240261A (en) * 2003-02-07 2004-08-26 Victor Co Of Japan Ltd Wavelength selective phase plate and projection display apparatus using the same
JP2010008808A (en) * 2008-06-27 2010-01-14 Kyocera Kinseki Corp Quartz wave plate
JP2010032927A (en) * 2008-07-30 2010-02-12 Kyocera Kinseki Corp Quartz crystal wavelength plate
JP2013025065A (en) * 2011-07-21 2013-02-04 Seiko Epson Corp Wave plate, polarization conversion element, polarization conversion unit and projection device
JP2013113984A (en) * 2011-11-28 2013-06-10 Sony Corp Projection apparatus

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004240261A (en) * 2003-02-07 2004-08-26 Victor Co Of Japan Ltd Wavelength selective phase plate and projection display apparatus using the same
JP2010008808A (en) * 2008-06-27 2010-01-14 Kyocera Kinseki Corp Quartz wave plate
JP2010032927A (en) * 2008-07-30 2010-02-12 Kyocera Kinseki Corp Quartz crystal wavelength plate
JP2013025065A (en) * 2011-07-21 2013-02-04 Seiko Epson Corp Wave plate, polarization conversion element, polarization conversion unit and projection device
JP2013113984A (en) * 2011-11-28 2013-06-10 Sony Corp Projection apparatus

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