JP2019203955A - Projector and multi-projection system - Google Patents

Abstract

To provide a projector that can prevent a deterioration in quality of a multi-projection image occurring when the projector has a plurality of illumination light sources.SOLUTION: A projector 200 comprises illumination light sources 101 and 102, a dichroic mirror 220, a phase difference plate 103, and a polarization conversion element 150. When any one of s-polarized light and p-polarized light being linearly polarized light is first polarized light and the other is second polarized light, the illumination light source 101 emits first illumination light of the second polarized light. The illumination light source 102 emits second illumination light. The dichroic mirror 220 has a specific polarized light reflection area 220R and a total reflection area 220T. The specific polarized light reflection area 220R transmits the second polarized light, and reflects the first polarized light and second illumination light. The total reflection area 220T reflects the first illumination light and second illumination light. The phase difference plate 103 converts the linearly polarized light into circularly polarized light. The polarization conversion element 150 transmits one of the first polarized light and second polarized light, shifts an optical axis of the other, and aligns the first illumination light and second illumination light with the first polarized light or the second polarized light.SELECTED DRAWING: Figure 18

Description

  The present invention relates to a projector and a multi-projection system.

  The multi-projection system has a plurality of projectors. The multi-projection system displays a multi-projected image on a screen or the like by projecting a plurality of images side by side on a screen or the like by a plurality of projectors.

  In the multi-projection system, each blended image is subjected to edge blending in order to make the boundary between the projected images inconspicuous. The edge blending process is a process of adjusting the brightness of the projected image so that the overlapping area between the projected images does not become too bright when adjacent images are projected by overlapping a predetermined area.

  Patent Document 1 describes an edge blending process that adjusts the brightness of a projected image so that a region of the projected image corresponding to a region where the projected images overlap is continuously darkened toward the end.

  The electrical edge blending process described in Patent Document 1 is effective for bright projection images, but sufficiently secures a dynamic range for adjusting the brightness for dark projection images. I can't. Therefore, in the electrical edge blending process, the overlapping area between the projected images becomes brighter with respect to the dark projected image, which becomes a factor of deteriorating the quality of the multi-projected image.

  In Patent Document 2, a light shielding plate is arranged between a projector and a screen, and an edge of the projected image becomes a shadow by being applied to the light shielding plate, and an area of the projected image corresponding to an overlapping area of the projected images is at the end. An edge blending process is described in which the brightness of a projected image is adjusted so as to be continuously dark.

  In the optical edge blending process as described in Patent Document 2, the brightness of the region of the projection image corresponding to the region where the projection images overlap can be adjusted regardless of the brightness of the projection image.

JP 2009-159372 A JP-A-3-53288

  The projector may have a plurality of illumination light sources. For example, a projector uses a blue laser light source and a phosphor as a plurality of illumination light sources. The blue laser light source emits blue laser light as blue illumination light. The phosphor converts the energy of the blue laser light emitted from the blue laser light source into yellow illumination light having a wavelength band including a red band and a green band. The projector separates yellow illumination light into red illumination light and green illumination light.

  The projector modulates red illumination light, green illumination light, and blue illumination light based on the image data of each color component to generate red image light, green image light, and blue image light. The projector synthesizes the red image light, the green image light, and the blue image light and projects them on a screen or the like. That is, blue image light corresponding to a blue image projected on a screen or the like is generated using a blue laser light source as an illumination light source. Red image light and green image light corresponding to a red image and a green image are generated using a phosphor as an illumination light source.

  The blue image light using the blue laser light source as the illumination light source, the red image light using the fluorescent material as the illumination light source, and the green image light differ in the orientation distribution of the projected image. In the optical edge blending process using the light shielding plate, color distribution is generated in the region of the projection image corresponding to the region where the projection images overlap due to the difference in the orientation distribution, which causes deterioration of the quality of the multi-projection image. .

  It is an object of the present invention to provide a projector and a multi-projection system that can suppress deterioration of the quality of a multi-projection image when the projector has a plurality of illumination light sources.

  In the present invention, when one of the s-polarized light and the p-polarized light that is linearly polarized light is the first polarized light and the other is the second polarized light, the first illumination light that is the second polarized light is emitted. One illumination light source, a second illumination light source that emits second illumination light, and an optical path of the first and second illumination light, transmitting the second polarized light, and 1st dichroic mirror which has 1 polarized light and the specific polarization reflective area which reflects the 2nd illumination light, and the total reflection area which reflects the 1st and 2nd illumination light, and the 1st dichroic mirror A phase difference plate disposed on the optical path of the first and second illumination light reflected by the light source and converting the linearly polarized light into circularly polarized light; and the first and second illumination light transmitted through the phase difference plate. Any one of the first polarized light and the second polarized light And a polarization conversion element that transmits the first polarization and shifts the optical axis of the other polarization and aligns the first and second illumination lights with the first polarization or the second polarization. I will provide a.

  In addition, the present invention includes a plurality of the projectors that project an image, and a plurality of light shielding plates that are arranged corresponding to the projector so as to shield a partial area of the image, and the plurality of projectors project Provided is a multi-projection system for displaying a plurality of images as a multi-projection image by overlapping the partial areas.

  According to the projector and multi-projection system of the present invention, it is possible to suppress the deterioration of the quality of the multi-projection image when the projector has a plurality of illumination light sources.

It is a block diagram which shows an example of the multi-projection system of 1st and 2nd embodiment. It is a figure which shows the brightness of the projection image displayed on a screen. It is a figure which shows the brightness of the multi projection image displayed on a screen. It is a block diagram which shows an example of the projector of 1st Embodiment. It is a block diagram which shows an example of the dichroic mirror in the projector of 1st Embodiment. It is a block diagram which shows an example of the dichroic mirror in the projector of 1st Embodiment. It is a figure which shows distribution of the brightness of red illumination light and green illumination light. It is a figure which shows distribution of the light intensity of the red illumination light and green illumination light in A1-A1 shown to FIG. 5A. It is a figure which shows distribution of the brightness of blue illumination light. It is a figure which shows distribution of the light intensity of the blue illumination light in A2-A2 shown to FIG. 6A. It is a figure which shows distribution of the brightness of s polarized light in blue illumination light. It is a figure which shows distribution of the light intensity of s polarization | polarized-light of the blue illumination light in A3-A3 shown to FIG. 7A. It is a figure which shows distribution of the brightness of the p polarization | polarized-light in blue illumination light. It is a figure which shows distribution of the light intensity of p polarization | polarized-light of the blue illumination light in A4-A4 shown to FIG. 8A. It is a figure which shows distribution of the brightness of red illumination light and green illumination light. It is a figure which shows distribution of the light intensity of red illumination light and green illumination light in A5-A5 shown to FIG. 9A. It is a figure which shows distribution of the brightness of blue illumination light. It is a figure which shows distribution of the light intensity of the blue illumination light in A6-A6 shown to FIG. 10A. It is a figure which shows distribution of the brightness of s polarized light in blue illumination light. It is a figure which shows distribution of the light intensity of the s polarization | polarized-light of the blue illumination light in A7-A7 shown to FIG. 11A. It is a figure which shows distribution of the brightness of the p polarization | polarized-light in blue illumination light. It is a figure which shows distribution of the p-polarized light intensity of the blue illumination light in A8-A8 shown to FIG. 12A. It is a block diagram which shows an example of a polarization conversion element. It is a figure which shows distribution of the brightness of red illumination light and green illumination light. It is a figure which shows distribution of the light intensity of red illumination light in A9-A9 shown to FIG. 14A, and green illumination light. It is a figure which shows distribution of the brightness of the blue illumination light in an illumination pupil. It is a figure which shows distribution of the light intensity of the blue illumination light in A10-A10 shown to FIG. 15A. It is a figure which shows distribution of the brightness of the blue illumination light in an illumination pupil. It is a figure which shows distribution of the light intensity of the blue illumination light in A11-A11 shown to FIG. 16A. It is a figure which shows distribution of the brightness of the blue illumination light in an illumination pupil. It is a figure which shows distribution of the light intensity of the blue illumination light in A12-A12 shown to FIG. 17A. It is a block diagram which shows an example of the projector of 2nd Embodiment. It is a block diagram which shows an example of the dichroic mirror in the projector of 2nd Embodiment. It is a block diagram which shows an example of the dichroic mirror in the projector of 2nd Embodiment. It is a figure which shows distribution of the brightness of red illumination light and green illumination light. It is a figure which shows distribution of the light intensity of the red illumination light in A21-A21 shown to FIG. 20A, and green illumination light. It is a figure which shows distribution of the brightness of blue illumination light. It is a figure which shows distribution of the light intensity of the blue illumination light in A22-A22 shown to FIG. 21A. It is a figure which shows distribution of the brightness of s polarized light in blue illumination light. It is a figure which shows distribution of the light intensity of s polarization | polarized-light of the blue illumination light in A23-A23 shown to FIG. 22A. It is a figure which shows distribution of the brightness of the p polarization | polarized-light in blue illumination light. It is a figure which shows distribution of the light intensity of p polarization | polarized-light of the blue illumination light in A24-A24 shown to FIG. 23A. It is a block diagram which shows an example of a polarization conversion element. It is a block diagram which shows an example of a polarization conversion element.

  A configuration example of a multi-projection system will be described with reference to FIGS. 1, 2A, and 2B. As shown in FIG. 1, the multi-projection system 1 includes a plurality of projectors PJ and a plurality of light shielding plates 10. The projector PJ projects the image IM on the screen SRN. FIG. 1 shows a state in which two projectors PJ are arranged in the horizontal direction. In order to distinguish between the two projectors PJ, the left projector PJ is a projector PJa, and the right projector PJ is a projector PJb.

  The light shielding plate 10 is disposed between the projector PJ and the screen SRN. The light shielding plate 10 is arranged for each projector PJ. The light shielding plate 10 corresponding to the projector PJa is referred to as a light shielding plate 10a, and the light shielding plate 10 corresponding to the projector PJb is referred to as a light shielding plate 10b.

  2A and 2B, the brightness of the projected image displayed on the screen SRN is shown by shading. In FIGS. 2A and 2B, only the projectors PJa and PJb and the screen SRN are shown for easy viewing of the projected image.

  As shown in FIG. 2A, the projector PJa projects the image IMa on the screen SRN. As shown in FIG. 1, the light shielding plate 10a is arranged corresponding to the projector PJa so as to shield a part of the image IMa. Specifically, the light shielding plate 10a is arranged so that the right region of the image IMa covers the light shielding plate 10a. Accordingly, the projector PJa projects the shadow from the light shielding plate 10a onto the screen SRN as a part of the image IMa.

  In the image IMa projected on the screen SRN, the area on the light shielding plate 10a corresponds to the shadow area of the light shielding plate 10a. In the region on the right side of the image IMa, the degree of light shielding by the light shielding plate 10a increases toward the right end. Accordingly, in the image IMa projected on the screen SRN, the degree of shadow by the light shielding plate 10a increases toward the right end. Therefore, in the image IMa projected on the screen SRN, the right region IMRa continuously becomes darker toward the right end. The image IMa projected on the screen SRN is defined as a projected image PIMa.

  As shown in FIG. 2A, the projector PJb projects the image IMb onto the screen SRN. As shown in FIG. 1, the light shielding plate 10b is arranged corresponding to the projector PJb so as to shield a part of the image IMb. Specifically, the light shielding plate 10b is arranged so that the left region of the image IMb covers the light shielding plate 10b. Accordingly, the projector PJb projects the shadow from the light shielding plate 10b onto the screen SRN as a part of the image IMb.

  In the image IMb projected on the screen SRN, an area on the light shielding plate 10b corresponds to a shadow area by the light shielding plate 10b. In the left region of the image IMb, the degree of light shielding by the light shielding plate 10b increases toward the left end. Accordingly, in the image IMb projected on the screen SRN, the degree of shadow by the light shielding plate 10b increases toward the left end. Therefore, in the image IMb projected on the screen SRN, the left region IMRb continuously becomes darker toward the left end. The image IMb projected on the screen SRN is defined as a projected image PIMb.

  As shown in FIG. 1 or FIG. 2B, the projector PJa and the projector PJb connect the image IMa and the image IMb to the screen SRN so that the region IMRa on the right side of the projection image PIMa and the region IMLb on the left side of the projection image PIMb overlap. Project to.

  That is, the multi-projection system 1 is configured such that a part of the plurality of projection images PIM is shielded from light by the light shielding plate 10, specifically, the region IMRa on the light shielding plate 10a in the projection image PIMa and the light shielding plate 10b in the projection image PIMb. The images IMa and IMb projected by the plurality of projectors PJa and PJb are displayed on the screen SRN as a multi-projected image MPIM so that the region IMLb overlaps.

  Therefore, the multi-projection system 1 uses the light shielding plates 10a and 10b to perform multi-projection that has been subjected to optical edge blending so that the brightness of the overlapping area between the projected image PIMa and the projected image PIMb is the same as the brightness of the other areas. The image MPIM can be displayed on the screen SRN.

[First Embodiment]
A configuration example of the projector PJ will be described with reference to FIG. A projector 100 according to the first embodiment shown in FIG. 3 corresponds to the projectors PJ (PJa and PJb) shown in FIGS. 1, 2A, and 2B. The projector 100 includes a light source 101, a phosphor 102, a dichroic mirror 120, lenses 131 to 137, reflection mirrors 141 to 143, a phase difference plate 103, and a polarization conversion element 150. In the first embodiment, the phase difference plate 103 is a first phase difference plate.

  Further, the projector 100 includes dichroic mirrors 105 and 106, reflective polarizing plates 107R, 107G, and 107B, image display elements 108R, 108G, and 108B, a color synthesis prism 109, a diaphragm 110, and a projection lens 111. With. In the first embodiment, the dichroic mirror 120 is a first dichroic mirror, the dichroic mirror 105 is a second dichroic mirror, and the dichroic mirror 106 is a third dichroic mirror.

  The light source 101 is a blue laser light source having an array structure in which a plurality of blue laser elements BL are arranged. The light source 101 emits blue laser light from a plurality of blue laser elements BL. The blue laser light is s-polarized light or p-polarized linearly polarized light. FIG. 3 shows a case where the blue laser light is s-polarized linearly polarized light. Blue laser light is applied to the dichroic mirror 120. In the first embodiment, the light source 101 is the first illumination light source, and the blue laser light is the first illumination light. Further, the s-polarized light is the first polarized light and the p-polarized light is the second polarized light.

  The dichroic mirror 120 is disposed so that the polarization direction of the blue laser light is s-polarized with respect to the dichroic mirror 120. The dichroic mirror 120 has an optical characteristic of reflecting s-polarized light and transmitting p-polarized light with respect to blue laser light. The lens 131 is, for example, a condenser lens. The blue laser light emitted from the light source 101 is reflected by the dichroic mirror 120, further condensed by the lens 131, and irradiated on the phosphor 102.

  The phosphor 102 has a phosphor layer and a reflecting surface. The fluorescent layer is yellow illumination light including a red band component and a green band component having an intensity corresponding to the energy of the light emitted from the light source 101, specifically, the energy intensity of the blue laser light emitted from the light source 101. Is generated. The reflecting surface reflects the blue laser light transmitted through the fluorescent layer and the yellow illumination light generated by the fluorescent layer.

  In the first embodiment, the phosphor 102 is used as the second illumination light source, and the yellow illumination light is used as the second illumination light. Accordingly, the projector 100 includes the light source 101 (blue laser element BL) as a first illumination light source and the phosphor 102 as a second illumination light source as a plurality of illumination light sources.

  Yellow illumination light, which is fluorescence generated by the phosphor 102, is applied to the dichroic mirror 120 via the lens 131. A part of the blue laser light is diffused by the phosphor 102 to become a randomly polarized light in which a plurality of polarized lights are mixed, and is irradiated to the dichroic mirror 120 via the lens 131. That is, the dichroic mirror 120 is disposed on the optical path of the blue laser light and the yellow illumination light. The dichroic mirror 120 has an optical characteristic of transmitting yellow illumination light.

  FIG. 4A shows a configuration example of the dichroic mirror 120. 4A shows a state where the dichroic mirror 120 is viewed from the side opposite to the light source 101, that is, a state where the dichroic mirror 120 is viewed from below in FIG. The dichroic mirror 120 has a specific polarization reflection region 120R and a transmission region 120T.

  The specific polarization reflection region 120R reflects the s-polarized light in the blue laser light and transmits the p-polarized light and the yellow illumination light in the blue laser light. The transmission region 120T transmits all polarized light including s-polarized light and p-polarized light in the blue laser light and yellow illumination light.

  The specific polarization reflection region 120R is disposed on the optical axis BLA of the blue laser element BL. The specific polarization reflection region 120R is formed to have an area larger than the light flux width of the blue laser light. Accordingly, all the blue laser beams emitted from the plurality of blue laser elements BL are reflected toward the lens 131 by the dichroic mirror 120. Further, the blue laser light is collected by the lens 131 and irradiated onto the phosphor 102.

  The specific polarization reflection region 120R is formed to have an area smaller than the light flux width of the diffused light irradiated from the phosphor 102 via the lens 131. Of the blue laser light emitted from the phosphor 102 to the specific polarization reflection region 120R, the p polarization component is transmitted through the specific polarization reflection region 120R, and the s polarization component is reflected by the specific polarization reflection region 120R and returned to the light source 101. . The blue laser light emitted from the phosphor 102 to the transmission region 120T passes through the transmission region 120T. The blue laser light transmitted through the dichroic mirror 120 is used as blue illumination light.

  Yellow illumination light irradiated from the phosphor 102 to the dichroic mirror 120 via the lens 131 passes through the specific polarization reflection region 120R and the transmission region 120T. As shown in FIG. 4B, the dichroic mirror 120 may be configured such that the specific polarization reflection region 120R is disposed on the optical axis BLA of the blue laser element BL, and the region other than the specific polarization reflection region 120R is the transmission region 120T. .

  The dichroic mirror 120 can be manufactured, for example, by forming a dielectric multilayer film in a predetermined region of a transparent material such as a glass plate or a prism. The region where the dielectric multilayer film is formed becomes the specific polarization reflection region 120R. The optical characteristics of the specific polarization reflection region 120R can be set according to the material and film thickness of the dielectric constituting the dielectric multilayer film.

  5A, FIG. 5B, FIG. 6A, FIG. 6B, FIG. 7A, FIG. 7B, FIG. 8A, and FIG. 8B, blue illumination light and blue illumination at a position Pa through which yellow illumination light passes through the dichroic mirror 120 are used. The brightness distribution of the red illumination light and the green illumination light included in the light and the yellow illumination light will be described. 5A, 5B, 6A, 6B, 7A, 7B, 8A, and 8B show cases where the dichroic mirror 120 has the shape shown in FIG. 4A.

  FIG. 5A shows the brightness distribution of the red illumination light and the green illumination light included in the yellow illumination light in a shade at the position Pa. FIG. 5B shows the brightness distribution of the red illumination light and the green illumination light in A1-A1 shown in FIG. 5A as the light intensity distribution. The red illumination light is composed of a red band component included in the yellow illumination light, and the green illumination light is composed of a green band component included in the yellow illumination light.

  The yellow illumination light is transmitted through the specific polarization reflection region 120R and the transmission region 120T of the dichroic mirror 120. Therefore, at the position Pa, as shown in FIG. 5A or 5B, the distribution of the brightness (light intensity) of the red illumination light and the green illumination light is uniform. The light intensity of the red illumination light and the green illumination light at the position Pa is defined as BR1.

  FIG. 6A corresponds to FIG. 5A and shows the brightness distribution of the blue illumination light in shades. FIG. 6B shows the brightness distribution of the blue illumination light in A2-A2 shown in FIG. 6A as the light intensity distribution. FIG. 7A corresponds to FIG. 6A and shows the distribution of brightness of s-polarized light in blue illumination light in shades. FIG. 7B shows the brightness distribution of the s-polarized light of the blue illumination light in A3-A3 shown in FIG. 7A as the light intensity distribution. FIG. 8A corresponds to FIG. 6A and shows the brightness distribution of the p-polarized light in the blue illumination light in shades. FIG. 8B shows the brightness distribution of the p-polarized light of the blue illumination light in A4-A4 shown in FIG. 8A as the light intensity distribution.

  The s-polarized light in the blue illumination light is transmitted through the transmission region 120T of the dichroic mirror 120 and reflected by the specific polarization reflection region 120R. Therefore, the s-polarized light in the blue illumination light is shielded as a result by the specific polarization reflection region 120R. Therefore, at the position Pa, as shown in FIG. 7A, the s-polarized light in the blue illumination light is shielded from the area corresponding to the specific polarization reflection area 120R, and the area corresponding to the transmission area 120T is red illumination light, and The brightness (light intensity) distribution is darker than that of the green illumination light.

  That is, as shown in FIG. 7B, the s-polarized light in the blue illumination light has a light intensity BR2 (BR2 <BR1) smaller than the light intensity BR1 of the red illumination light and the green illumination light in the region corresponding to the transmission region 120T. And the region corresponding to the specific polarization reflection region 120R has a light intensity BR3 (BR2> BR3 = 0) smaller than the light intensity BR2 of the region corresponding to the transmission region 120T.

  The p-polarized light in the blue illumination light is transmitted through the specific polarization reflection region 120R and the transmission region 120T of the dichroic mirror 120. Therefore, at position Pa, as shown in FIG. 8A, the p-polarized light in the blue illumination light is darker than the red illumination light and the green illumination light, and the distribution of brightness (light intensity) is uniform. That is, as shown in FIG. 8B, the p-polarized light in the blue illumination light has a light intensity BR4 (BR4 <BR1) that is smaller than the light intensity BR1 of the red illumination light and the green illumination light at the position Pa.

  Therefore, the blue illumination light including the s-polarized light having the brightness (light intensity) distribution shown in FIGS. 7A and 7B and the p-polarized light having the brightness (light intensity) distribution shown in FIGS. 8A and 8B is shown in FIG. As shown in 6A, the region corresponding to the transmission region 120T has the same brightness as the red illumination light and the green illumination light, and the region corresponding to the specific polarization reflection region 120R is the red illumination light and the green illumination. It is a distribution of brightness (light intensity) that is darker than light.

  That is, as shown in FIG. 6B, the blue illumination light has the same light intensity BR5 (BR5 = BR1) as the light intensity BR1 of the red illumination light and the green illumination light in the region corresponding to the transmission region 120T. The region corresponding to the polarization reflection region 120R has a light intensity BR6 (BR6 <BR5) smaller than the light intensity BR5 of the region corresponding to the transmission region 120T. A difference between the light intensity BR5 and the light intensity BR6 of the blue illumination light at the position Pa is defined as a light intensity difference BRDa.

  The lenses 132 and 133 shown in FIG. 3 are, for example, fly-eye lenses. As shown in FIG. 3, the blue illumination light and the yellow illumination light transmitted through the dichroic mirror 120 are reflected by the reflection mirror 141. Further, the blue illumination light and the yellow illumination light make the illumination distribution of the red illumination light, the green illumination light, and the blue illumination light emitted to the image display elements 108R, 108G, and 108B uniform by the lenses 132 and 133, respectively.

  The phase difference plate 103 is disposed between the dichroic mirror 120 and the polarization conversion element 150 on the optical path of blue illumination light and yellow illumination light. FIG. 3 shows an example in which the phase difference plate 103 is disposed between the lens 132 and the lens 133. The phase difference plate 103 is arranged in a direction for converting linearly polarized light into circularly polarized light. The phase difference plate 103 is, for example, a λ / 4 phase difference plate.

  9A, 9B, 10A, 10B, 11A, 11B, 12A, and 12B, the blue illumination light and the blue light at the position Pb where the yellow illumination light has transmitted through the phase difference plate 103 are used. The brightness distribution of the red illumination light and the green illumination light included in the illumination light and the yellow illumination light will be described. 9A, 9B, 10A, 10B, 11A, 11B, 12A, and 12B are illustrated in FIGS. 5A, 5B, 6A, 6B, 7A, 7B, 8A, and 8A. Each corresponds to FIG. 8B.

  FIG. 9A shows the distribution of brightness of red illumination light and green illumination light included in yellow illumination light in shades. FIG. 9B shows the distribution of brightness of red illumination light and green illumination light in A5-A5 shown in FIG. 9A as light intensity distribution. At the position Pb, as shown in FIG. 9A, the distribution of the brightness (light intensity) of the red illumination light and the green illumination light is uniform. As shown in FIG. 9B, the light intensity of the red illumination light and the green illumination light at the position Pb is BR7.

  FIG. 10A corresponds to FIG. 9A and shows the distribution of brightness of the blue illumination light in shades. FIG. 10B shows the brightness distribution of the blue illumination light in A6-A6 shown in FIG. 10A as the light intensity distribution. FIG. 11A corresponds to FIG. 10A and shows the distribution of brightness of s-polarized light in blue illumination light in shades. FIG. 11B shows the brightness distribution of the s-polarized light of the blue illumination light in A7-A7 shown in FIG. 11A as the light intensity distribution. FIG. 12A corresponds to FIG. 10A and shows the brightness distribution of the p-polarized light in the blue illumination light in shades. FIG. 12B shows the distribution of the brightness of the p-polarized light of the blue illumination light in A8-A8 shown in FIG. 12A as the light intensity distribution.

  The phase difference plate 103 converts blue illumination light, which is linearly polarized light, into circularly polarized light. The phase difference plate 103 converts the blue illumination light into circularly polarized light, so that the s-polarized light and the p-polarized light in the blue illumination light have the same brightness (light intensity) distribution as shown in FIGS. 11A and 12A. be able to. In the s-polarized light and p-polarized light in the blue illumination light, the region corresponding to the transmission region 120T is darker than the red illumination light and green illumination light, and the region corresponding to the specific polarization reflection region 120R is the transmission region 120T. The distribution of brightness (light intensity) is darker than the corresponding area.

  That is, as shown in FIG. 11B, the s-polarized light in the blue illumination light has a light intensity BR8 (BR8 <BR7) smaller than the light intensity BR7 of the red illumination light and the green illumination light in the region corresponding to the transmission region 120T. And the region corresponding to the specific polarization reflection region 120R has a light intensity BR9 (BR9 <BR8) smaller than the light intensity BR8 of the region corresponding to the transmission region 120T.

  As shown in FIG. 12B, the p-polarized light in the blue illumination light has a light intensity BR10 (BR10 <BR7) smaller than the light intensity BR7 of the red illumination light and the green illumination light in the region corresponding to the transmission region 120T. The region corresponding to the specific polarization reflection region 120R has a light intensity BR11 (BR11 <BR10) smaller than the light intensity BR10 of the region corresponding to the transmission region 120T.

  Accordingly, the blue illumination light including the s-polarized light having the brightness (light intensity) distribution shown in FIGS. 11A and 11B and the p-polarized light having the brightness (light intensity) distribution shown in FIGS. 12A and 12B is shown in FIG. As shown in FIG. 10A, the region corresponding to the transmission region 120T has the same brightness as the red illumination light and the green illumination light, and the region corresponding to the specific polarization reflection region 120R is the red illumination light and the green illumination. It is a distribution of brightness (light intensity) that is darker than light.

  That is, as shown in FIG. 10B, the blue illumination light has the same light intensity BR12 (BR12 = BR7) as the light intensity BR7 of the red illumination light and the green illumination light in the region corresponding to the transmission region 120T. The region corresponding to the polarization reflection region 120R has a light intensity BR13 (BR13 <BR12) smaller than the light intensity BR12 of the region corresponding to the transmission region 120T. A difference between the light intensity BR12 and the light intensity BR13 of the blue illumination light at the position Pb is defined as a light intensity difference BRDb.

  At the position Pb, it is preferable that the s-polarized light intensities BR8 and BR9 and the p-polarized light intensities BR10 and BR11 in the blue illumination light have the same value, respectively. The light intensity difference BRDa and the light intensity difference BRDb are substantially the same at the position Pa where the blue illumination light has passed through the dichroic mirror 120 and the position Pb where the blue illumination light has passed through the phase difference plate 103.

  As shown in FIG. 3, the polarization conversion element 150 is arranged on the optical path of the blue illumination light and the yellow illumination light transmitted through the phase difference plate 103. The blue illumination light and the yellow illumination light transmitted through the phase difference plate 103 are incident on the polarization conversion element 150.

  FIG. 13 shows a configuration example of the polarization conversion element 150. The polarization conversion element 150 includes a polarization beam splitter 151 and a phase difference plate 152. In the first embodiment, the phase difference plate 152 is a second phase difference plate. The polarization beam splitter 151 reflects either the s-polarized light or the p-polarized light and transmits the other. FIG. 13 shows a state in which the polarizing beam splitter 151 reflects s-polarized light and transmits p-polarized light.

  The phase difference plate 152 converts one of s-polarized light and p-polarized light into the other. FIG. 13 shows a state where the phase difference plate 152 converts s-polarized light into p-polarized light. The phase difference plate 152 is, for example, a λ / 2 phase difference plate. The specific polarization reflection region 120R of the dichroic mirror 120 and the phase difference plate 152 of the polarization conversion element 150 correspond to each other.

  14A, FIG. 14B, FIG. 15A, FIG. 15B, FIG. 16A, FIG. 16B, FIG. 17A, and FIG. 17B, the blue illumination light and the blue light at the position Pc where the yellow illumination light is transmitted through the polarization conversion element 150 are used. The brightness distribution of the red illumination light and the green illumination light included in the illumination light and the yellow illumination light will be described. The position Pc corresponds to the position of the illumination pupil. 14A, 14B, 15A, 15B, 16A, 16B, 17A, and 17B are illustrated in FIGS. 9A, 9B, 10A, 10B, 11A, 11B, 12A, and 12A. Each corresponds to FIG. 12B.

  FIG. 14A shows the distribution of brightness of red illumination light and green illumination light included in yellow illumination light in shades. FIG. 14B shows the brightness distribution of the red illumination light and the green illumination light in A9-A9 shown in FIG. 14A as the light intensity distribution. The yellow illumination light is aligned with the p-polarized light by the polarization conversion element 150. In the illumination pupil (position Pc), as shown in FIG. 14A, the distribution of the brightness (light intensity) of the red illumination light and the green illumination light is uniform. As shown in FIG. 14B, the light intensity of the red illumination light and the green illumination light at the illumination pupil is BR14.

  FIG. 15A corresponds to FIG. 14A and shows the distribution of the brightness of the blue illumination light at the illumination pupil (position Pc) in shades. FIG. 15B shows the brightness distribution of the blue illumination light in A10-A10 shown in FIG. 15A as the light intensity distribution. FIG. 16A and FIG. 17A correspond to FIG. 15A and show the brightness distribution of the blue illumination light in shades. FIG. 16B shows the brightness distribution of the blue illumination light in A11-A11 shown in FIG. 16A as the light intensity distribution. FIG. 17B shows the brightness distribution of the blue illumination light in A12-A12 shown in FIG. 17A as the light intensity distribution.

  16A and 16B correspond to FIGS. 11A and 11B. The brightness (light intensity) distribution of the blue illumination light shown in FIGS. 16A and 16B corresponds to the brightness (light intensity) distribution of the s-polarized light in the blue illumination light incident on the polarization conversion element 150. 17A and 17B correspond to FIGS. 12A and 12B. The brightness (light intensity) distribution of the blue illumination light shown in FIGS. 17A and 17B corresponds to the brightness (light intensity) distribution of the p-polarized light in the blue illumination light incident on the polarization conversion element 150.

  As shown in FIG. 13, the polarization conversion element 150 transmits p-polarized light. As shown in FIG. 17A, the p-polarized light in the blue illumination light incident on the polarization conversion element 150 has a region corresponding to the transmission region 120T that is darker than the red illumination light and the green illumination light, and the specific polarization reflection region 120R. The region corresponding to 1 has a distribution of brightness (light intensity) darker than the region corresponding to the transmission region 120T, and transmits through the polarization conversion element 150.

  That is, the p-polarized light in the blue illumination light incident on the polarization conversion element 150 has a light intensity smaller than the light intensity BR14 of the red illumination light and the green illumination light in the region corresponding to the transmission region 120T, as shown in FIG. 17B. The polarization conversion element 150 has BR19 (BR19 <BR14), and has a light intensity BR20 (BR20 <BR19) smaller than the light intensity BR19 in the area corresponding to the transmission area 120T in the area corresponding to the specific polarization reflection area 120R. Transparent.

  As shown in FIG. 13, the polarization conversion element 150 shifts the optical axis of the s-polarized light in the reflection direction by reflecting the s-polarized light incident on the polarization conversion element 150 in the polarization beam splitter 151. The polarization conversion element 150 converts the s-polarized light into p-polarized light by the phase difference plate 152. Accordingly, the blue illumination light is aligned with the p-polarized light by the polarization conversion element 150.

  As shown in FIGS. 16A and 16B, the s-polarized light in the blue illumination light incident on the polarization conversion element 150 has the brightness (light intensity) distribution shown in FIGS. 11A and 11B shifted in the reflection direction by the polarization conversion element 150. The light is emitted from the polarization conversion element 150 as p-polarized blue illumination light having a distribution of brightness (light intensity).

  In the s-polarized light in the blue illumination light incident on the polarization conversion element 150, the region corresponding to the transmission region 120T is darker than the red illumination light and the green illumination light, and the region corresponding to the specific polarization reflection region 120R is the transmission region. The light is emitted from the polarization conversion element 150 as p-polarized blue illumination light having a distribution of brightness (light intensity) darker than the region corresponding to 120T.

  That is, the s-polarized light in the blue illumination light incident on the polarization conversion element 150 has a light intensity smaller than the light intensity BR14 of the red illumination light and the green illumination light in the region corresponding to the transmission region 120T, as shown in FIG. 16B. P-polarized blue illumination light having BR17 (BR17 <BR14) and having a light intensity BR18 (BR18 <BR17) that is smaller than the light intensity BR17 in the region corresponding to the transmission region 120T in the region corresponding to the specific polarization reflection region 120R. And emitted from the polarization conversion element 150.

  Therefore, as shown in FIG. 15A, the blue illumination light that has been aligned to the p-polarized light by the polarization conversion element 150 has the same brightness as the red illumination light and the green illumination light in the region corresponding to the transmission region 120T. The region corresponding to the specific polarization reflection region 120R has a distribution of brightness (light intensity) that is darker than red illumination light and green illumination light.

  That is, as shown in FIG. 15B, the blue illumination light emitted from the polarization conversion element 150 has the same light intensity BR15 (BR15) as the light intensity BR14 of the red illumination light and the green illumination light in the region corresponding to the transmission region 120T. = BR14), and the region corresponding to the specific polarization reflection region 120R has a light intensity BR16 (BR16 <BR15) smaller than the light intensity BR15 of the region corresponding to the transmission region 120T. A difference between the light intensity BR15 and the light intensity BR16 of the blue illumination light at the illumination pupil (position Pc) is defined as a light intensity difference BRDc.

  In the projector 100 and the multi-projection system 1 using the projector 100, the blue illumination light emitted from the plurality of blue laser elements BL constituting the light source 101 is converted from linearly polarized light to circularly polarized light by the phase difference plate 103, and further polarization conversion is performed. The element 150 transmits the p-polarized light in the blue illumination light and shifts the optical axis of the s-polarized light.

  Therefore, according to the projector 100 and the multi-projection system 1, the light intensity difference BRDc of the blue illumination light at the illumination pupil (position Pc) is made smaller than the light intensity differences BRDa and BRDb of the blue illumination light at the positions Pa and Pb. Therefore, variation in the brightness of the blue illumination light can be reduced.

  As shown in FIG. 3, the dichroic mirror 105 is disposed on the optical path of the blue illumination light and the yellow illumination light transmitted through the polarization conversion element 150. The blue illumination light and the yellow illumination light aligned with the P-polarized light by the polarization conversion element 150 are applied to the dichroic mirror 105 via the lens 134. The lens 134 is a condensing lens, for example. The dichroic mirror 105 separates incident blue illumination light and yellow illumination light.

  The yellow illumination light YLL separated by the dichroic mirror 105 is reflected by the reflection mirror 142. The dichroic mirror 106 is disposed on the optical path of the yellow illumination light YLL. The yellow illumination light YLL reflected by the reflection mirror 142 is applied to the dichroic mirror 106. The dichroic mirror 106 separates incident light by reflection and transmission using the separation wavelength as a separation boundary.

  The dichroic mirror 106 separates the yellow illumination light YLL into a red illumination light RLL including a red band component and a green illumination light GLL including a green band component. In FIG. 3, the dichroic mirror 106 separates the green illumination light GLL and the red illumination light RLL by reflecting the green illumination light GLL with respect to the incident yellow illumination light YLL and transmitting the red illumination light RLL. Here, the reflectance of the green illumination light GLL and the transmittance of the red illumination light RLL are 100% reflectance on the short wavelength side and 100% transmittance on the long wavelength side with the separation wavelength as a boundary.

  At wavelengths near the separation wavelength, the reflectance of the green illumination light GLL and the transmittance of the red illumination light RLL are small, so it can be said that the separation boundary has a width centered on the separation wavelength. Depending on the width of the separation boundary, the red illumination light RLL includes a component in the green wavelength band, and the green illumination light GLL includes a component in the red wavelength band. It is ideal from the viewpoint of the utilization efficiency of light energy that there is no width of the separation boundary.

  The red illumination light RLL separated by the dichroic mirror 106 is applied to the reflective polarizing plate 107R through the lens 135. The green illumination light GLL separated by the dichroic mirror 106 is applied to the reflective polarizing plate 107G through the lens 136. The blue illumination light BLL separated by the dichroic mirror 105 is reflected by the reflection mirror 143 and irradiated to the reflective polarizing plate 107B through the lens 137.

  The reflective polarizing plates 107R, 107G, and 107B reflect either the s-polarized light or the p-polarized light and transmit the other. FIG. 3 shows a state in which the reflective polarizing plates 107R, 107G, and 107B reflect s-polarized light and transmit p-polarized light. Wire grids may be used as the reflective polarizing plates 107R, 107G, and 107B. The p-polarized red illumination light RLL, green illumination light GLL, and blue illumination light BLL are respectively transmitted through the reflective polarizing plates 107R, 107G, and 107B, and are respectively transmitted to the image display elements 108R, 108G, and 108B. Irradiated.

  The image display element 108R modulates the red illumination light RLL based on the image data of the red component, and generates s-polarized red image light RML. The image display element 108G modulates the green illumination light GLL based on the image data of the green component, and generates s-polarized green image light GML. The image display element 108B optically modulates the blue illumination light BLL based on the blue component image data to generate s-polarized blue image light BML. That is, the image display element 108R functions as a red image light modulation element, the image display element 108G functions as a green image light modulation element, and the image display element 108B functions as a blue image light modulation element.

  The red image light RML, the green image light GML, and the blue image light BML generated by the image display elements 108R, 108G, and 108B are reflected by the reflective polarizing plates 107R, 107G, and 107B, respectively, and color synthesis is performed. Irradiated to the prism 109. The color combining prism 109 combines the red image light RML, the green image light GML, and the blue image light BML by reflecting the red image light RML and the blue image light BML and transmitting the green image light GML.

  The red image light RML, the green image light GML, and the blue image light BML synthesized by the color synthesis prism 109 are projected onto the screen SRN and the like via the aperture 110 and the projection lens 111 as shown in FIG. 1 or FIG. Is done. As a result, the projector 100 displays a full-color image IM obtained by combining the red image light RML, the green image light GML, and the blue image light BML on the screen SRN or the like.

  As shown in FIG. 3, the position Pd of the diaphragm 110 corresponds to the position of the projection pupil. The illumination pupil and the projection pupil have a conjugate relationship. Therefore, the brightness distribution of the red image light RML, the green image light GML, and the blue image light BML at the position Pd corresponding to the position of the projection pupil is the red illumination light RLL at the position Pc corresponding to the position of the illumination pupil. This corresponds to the brightness distribution of the green illumination light GLL and the blue illumination light BLL.

  A state in which the phase difference plate 103 is not disposed is taken as a comparative example. In the comparative example, the brightness distributions of the red image light RML, the green image light GML, and the blue image light BML at the position Pd corresponding to the position of the projection pupil are the red illumination light RLL, the green illumination light GLL at the position Pa, This corresponds to the brightness distribution of the blue illumination light BLL.

  Therefore, according to the projector 100 and the multi-projection system 1, the blue illumination light BLL is converted into circularly polarized light by the phase difference plate 103, and the s-polarized light axis of the blue illumination light is shifted by the polarization conversion element 150. As compared with the comparative example, it is possible to reduce the variation in the brightness of the blue image light BLL in the projection pupil.

  Therefore, according to the projector 100 and the multi-projection system 1, the color distribution generated by the light shielding plate 10 can be reduced by reducing the variation in the brightness of the blue image light BLL in the projection pupil. According to the projector 100 and the multi-projection system 1, when the projector 100 includes the blue laser element BL and the phosphor 102, which are a plurality of illumination light sources, deterioration of the quality of the multi-projection image can be suppressed.

[Second Embodiment]
A configuration example of the projector PJ will be described with reference to FIG. A projector 200 of the second embodiment shown in FIG. 18 corresponds to the projectors PJ (PJa and PJb) shown in FIGS. 1, 2A, and 2B. FIG. 18 corresponds to FIG. In order to make the explanation easy to understand, the same components as those of the projector 100 of the first embodiment are denoted by the same reference numerals.

  The projector 200 according to the second embodiment is different from the projector 100 according to the first embodiment in the configuration of the dichroic mirror 220 corresponding to the dichroic mirror 120 and the positional relationship between the light source 101 and the phosphor 102 with respect to the dichroic mirror 220. Different.

  As shown in FIG. 18, the projector 200 includes a light source 101, a phosphor 102, a dichroic mirror 220, lenses 131 to 137, reflection mirrors 141 to 143, a phase difference plate 103, and a polarization conversion element 150. Prepare. In the second embodiment, the phase difference plate 103 is a first phase difference plate.

  Further, the projector 200 includes dichroic mirrors 105 and 106, reflective polarizing plates 107R, 107G, and 107B, image display elements 108R, 108G, and 108B, a color synthesis prism 109, a diaphragm 110, and a projection lens 111. With.

  In the second embodiment, the dichroic mirror 220 is a first dichroic mirror, the dichroic mirror 105 is a second dichroic mirror, and the dichroic mirror 106 is a third dichroic mirror.

  The light source 101 emits blue laser light from a plurality of blue laser elements BL. The blue laser light is s-polarized light or p-polarized linearly polarized light. FIG. 18 shows a case where the blue laser light is p-polarized linearly polarized light. Blue laser light is applied to the dichroic mirror 220. In the second embodiment, the light source 101 is the first illumination light source, and the blue laser light is the first illumination light. Further, the s-polarized light is the first polarized light and the p-polarized light is the second polarized light.

  The dichroic mirror 220 is arranged so that the polarization direction of the blue laser light is s-polarized with respect to the dichroic mirror 220. The dichroic mirror 220 has an optical characteristic of reflecting s-polarized light and transmitting p-polarized light with respect to blue laser light. The blue laser light emitted from the light source 101 passes through the dichroic mirror 220, is further collected by the lens 131, and is applied to the phosphor 102.

  The phosphor 102 has a phosphor layer and a reflecting surface. The fluorescent layer is yellow illumination light including a red band component and a green band component having an intensity corresponding to the energy of the light emitted from the light source 101, specifically, the energy intensity of the blue laser light emitted from the light source 101. Is generated. The reflecting surface reflects the blue laser light transmitted through the fluorescent layer and the yellow illumination light generated by the fluorescent layer.

  In the second embodiment, the phosphor 102 is used as the second illumination light source, and the yellow illumination light is used as the second illumination light. Therefore, the projector 200 includes the light source 101 (blue laser element BL) as a first illumination light source and the phosphor 102 as a second illumination light source as a plurality of illumination light sources.

  Yellow illumination light, which is fluorescence generated by the phosphor 102, is applied to the dichroic mirror 220 via the lens 131. A part of the blue laser light is diffused by the phosphor 102 to become a randomly polarized light in which a plurality of polarized lights are mixed, and is irradiated to the dichroic mirror 220 through the lens 131. That is, the dichroic mirror 220 is disposed on the optical path of the blue laser light and the yellow illumination light. The dichroic mirror 220 has an optical characteristic of reflecting yellow illumination light.

  FIG. 19A shows a configuration example of the dichroic mirror 220. FIG. 19A shows a state where the dichroic mirror 220 is viewed from the side opposite to the light source 101, that is, a state where the dichroic mirror 220 is viewed from below in FIG. The dichroic mirror 220 has a specific polarization reflection region 220R and a total reflection region 220T.

  The specific polarization reflection region 220R transmits the p-polarized light in the blue laser light and reflects the s-polarized light and the yellow illumination light in the blue laser light. The total reflection region 220T reflects all polarized light including s-polarized light and p-polarized light in the blue laser light and yellow illumination light.

  The specific polarization reflection region 220R is disposed on the optical axis BLA of the blue laser element BL. The specific polarization reflection region 220R is formed so as to have an area larger than the luminous flux width of the blue laser light. Accordingly, all the blue laser beams emitted from the plurality of blue laser elements BL are transmitted through the dichroic mirror 220 and irradiated onto the lens 131. Further, the blue laser light is collected by the lens 131 and irradiated onto the phosphor 102.

  The specific polarization reflection region 220 </ b> R is formed to have an area smaller than the light flux width of the diffused light irradiated from the phosphor 102 via the lens 131. Of the blue laser light emitted from the phosphor 102 to the specific polarization reflection region 220R, the s-polarized component is reflected toward the reflection mirror 141 by the specific polarization reflection region 220R. Of the blue laser light emitted from the phosphor 102 to the specific polarization reflection region 220R, the p-polarized light component is transmitted through the specific polarization reflection region 120R and returned to the light source 101.

  The blue laser light emitted from the phosphor 102 to the total reflection region 220T is reflected toward the reflection mirror 141 by the total reflection region 220T. The blue laser light reflected by the dichroic mirror 220 toward the reflection mirror 141 is used as blue illumination light.

  The yellow illumination light irradiated from the phosphor 102 to the dichroic mirror 220 via the lens 131 is reflected toward the reflection mirror 141 by the specific polarization reflection region 220R and the total reflection region 220T. As shown in FIG. 19B, the dichroic mirror 220 may be configured such that the specific polarization reflection region 220R is disposed on the optical axis BLA of the blue laser element BL, and the region other than the specific polarization reflection region 220R is the total reflection region 220T. Good.

  The dichroic mirror 220 uses, for example, a transparent material such as a glass plate or a prism, and forms, for example, a dielectric multilayer film in a region that becomes the specific polarization reflection region 220R, and a metal film or a dielectric multilayer in the region that becomes the total reflection region 220T. It can be produced by forming a reflective film such as a film. The optical characteristics of the specific polarization reflection region 120R can be set according to the material and film thickness of the dielectric constituting the dielectric multilayer film.

  20A, 20B, FIG. 21A, FIG. 21B, FIG. 22A, FIG. 22B, FIG. 23A, and FIG. 23B, the blue illumination at the position Pe where the blue illumination light and the yellow illumination light are reflected by the dichroic mirror 220 is used. The brightness distribution of the red illumination light and the green illumination light included in the light and the yellow illumination light will be described. 20A, 20B, 21A, 21B, 22A, 22B, 23A, and 23B show cases where the dichroic mirror 220 has the shape shown in FIG. 19A.

  The position Pe shown in FIG. 18 corresponds to the position Pa shown in FIG. The region corresponding to the specific polarization reflection region 220R at the position Pe corresponds to the region corresponding to the specific polarization reflection region 120R at the position Pa. The region corresponding to the total reflection region 220T at the position Pe corresponds to the region corresponding to the transmission region 120T at the position Pa.

  FIG. 20A shows the brightness distribution of the red illumination light and the green illumination light included in the yellow illumination light in a shade at the position Pe. FIG. 21B shows the brightness distribution of red illumination light and green illumination light in A21-A21 shown in FIG. 20A as the light intensity distribution. The red illumination light is composed of a red band component included in the yellow illumination light, and the green illumination light is composed of a green band component included in the yellow illumination light.

  The yellow illumination light reflects the specific polarization reflection region 220R and the total reflection region 220T of the dichroic mirror 220. Therefore, at the position Pe, as shown in FIG. 20A or 20B, the distribution of the brightness (light intensity) of the red illumination light and the green illumination light is uniform. The light intensity of the red illumination light and the green illumination light at the position Pe is BR21.

  The distribution of the brightness (light intensity) of the red illumination light and the green illumination light shown in FIGS. 20A and 20B is the brightness (light intensity) of the red illumination light and the green illumination light shown in FIGS. 5A and 5B. Corresponds to the distribution of. The light intensity BR21 of the red illumination light and the green illumination light at the position Pe corresponds to the light intensity BR1 of the red illumination light and the green illumination light at the position Pa.

  FIG. 21A corresponds to FIG. 20A and shows the distribution of brightness of the blue illumination light in shades. 21B shows the brightness distribution of the blue illumination light in A22-A22 shown in FIG. 21A as the light intensity distribution. FIG. 22A corresponds to FIG. 21A and shows the brightness distribution of the s-polarized light in the blue illumination light in shades. FIG. 22B shows the brightness distribution of the s-polarized light of the blue illumination light in A23-A23 shown in FIG. 22A as the light intensity distribution. FIG. 23A corresponds to FIG. 21A, and shows the distribution of brightness of p-polarized light in blue illumination light in shades. FIG. 23B shows the brightness distribution of the p-polarized light of the blue illumination light in A24-A24 shown in FIG. 23A as the light intensity distribution.

  The s-polarized light in the blue illumination light reflects the specific polarization reflection region 220R and the total reflection region 220T of the dichroic mirror 220. Therefore, at the position Pe, as shown in FIG. 22A, the s-polarized light in the blue illumination light is darker than the red illumination light and the green illumination light, and the distribution of brightness (light intensity) is uniform. That is, as shown in FIG. 22B, the s-polarized light in the blue illumination light has a light intensity BR22 (BR22 <BR21) that is smaller than the light intensity BR21 of the red illumination light and the green illumination light at the position Pe.

  The distribution of brightness (light intensity) of s-polarized light in the blue illumination light shown in FIGS. 22A and 22B corresponds to the distribution of brightness (light intensity) of p-polarization in the blue illumination light shown in FIGS. 8A and 8B. The s-polarized light intensity BR22 of the blue illumination light at the position Pe corresponds to the p-polarized light intensity BR4 of the blue illumination light at the position Pa.

  The p-polarized light in the blue illumination light is transmitted through the specific polarization reflection region 220R of the dichroic mirror 220 and reflected by the total reflection region 220T. Therefore, the p-polarized light in the blue illumination light is not irradiated to the region corresponding to the specific polarization reflection region 220R at the position Pe. Therefore, at the position Pe, the p-polarized light in the blue illumination light is not irradiated to the region corresponding to the specific polarization reflection region 220R and the region corresponding to the total reflection region 220T is red illumination light as shown in FIG. 23A. And a distribution of brightness (light intensity) that is darker than the green illumination light.

  That is, as shown in FIG. 23B, the p-polarized light in the blue illumination light has a light intensity BR23 (BR23 <BR21) smaller than the light intensity BR21 of the red illumination light and the green illumination light in the region corresponding to the total reflection region 220T. In the region corresponding to the specific polarization reflection region 220R, the light intensity BR24 (BR23> BR4 = 0) is smaller than the light intensity BR23 in the region corresponding to the total reflection region 220T.

  The distribution of brightness (light intensity) of p-polarized light in the blue illumination light shown in FIGS. 23A and 23B corresponds to the distribution of brightness (light intensity) of s-polarized light in the blue illumination light shown in FIGS. 7A and 7B. The p-polarized light intensities BR23 and BR24 of the blue illumination light at the position Pe correspond to the s-polarized light intensities BR2 and BR3 of the blue illumination light at the position Pa.

  Therefore, the blue illumination light including the s-polarized light having the brightness (light intensity) distribution shown in FIGS. 22A and 22B and the p-polarized light having the brightness (light intensity) distribution shown in FIGS. 23A and 23B is shown in FIG. As shown in 21A, the region corresponding to the total reflection region 220T has the same brightness as the red illumination light and the green illumination light, and the region corresponding to the specific polarization reflection region 220R is the red illumination light and the green color. The brightness (light intensity) distribution is darker than the illumination light.

  That is, as shown in FIG. 21B, the blue illumination light has the same light intensity BR25 (BR25 = BR21) as the light intensity BR21 of the red illumination light and the green illumination light in the region corresponding to the total reflection region 220T. The region corresponding to the specific polarization reflection region 220R has a light intensity BR26 (BR26 <BR25) smaller than the light intensity BR25 of the region corresponding to the total reflection region 220T. A difference between the light intensity BR25 and the light intensity BR26 of the blue illumination light at the position Pe is defined as a light intensity difference BRDe.

  The brightness (light intensity) distribution of the blue illumination light shown in FIGS. 21A and 21B corresponds to the brightness (light intensity) distribution of the blue illumination light shown in FIGS. 6A and 6B. The light intensity BR25 and BR26 of the blue illumination light at the position Pe corresponds to the light intensity BR5 and BR6 of the blue illumination light at the position Pa. The light intensity difference BRDe of the blue illumination light at the position Pe corresponds to the light intensity difference BRDe of the blue illumination light at the position Pa.

  As shown in FIG. 18, the blue illumination light and the yellow illumination light reflected by the dichroic mirror 220 are further reflected by the reflection mirror 141. The blue illumination light and the yellow illumination light equalize the illumination distribution of the red illumination light, the green illumination light, and the blue illumination light applied to the image display elements 108R, 108G, and 108B by the lenses 132 and 133.

  The phase difference plate 103 is disposed between the dichroic mirror 120 and the polarization conversion element 150 on the optical path of blue illumination light and yellow illumination light. FIG. 18 shows a state where the phase difference plate 103 is disposed between the lens 132 and the lens 133 as an example. The phase difference plate 103 is arranged in a direction for converting linearly polarized light into circularly polarized light. The phase difference plate 103 is, for example, a λ / 4 phase difference plate.

  9A, 9B, 10A, 10B, 11A, 11B, 12A, and 12B, the blue illumination light and the blue color at the position Pf where the yellow illumination light is transmitted through the phase difference plate 103 are used. The brightness distribution of the red illumination light and the green illumination light included in the illumination light and the yellow illumination light will be described. 9A, 9B, 10A, 10B, 11A, 11B, 12A, and 12B are illustrated in FIGS. 20A, 20B, 21A, 21B, 22A, 22B, 23A, and Each corresponds to FIG. 23B.

  The position Pf shown in FIG. 18 corresponds to the position Pb shown in FIG. The region corresponding to the specific polarization reflection region 220R at the position Pf corresponds to the region corresponding to the specific polarization reflection region 120R at the position Pb. The region corresponding to the total reflection region 220T at the position Pf corresponds to the region corresponding to the transmission region 120T at the position Pb.

  At the position Pf, as shown in FIG. 9A, the distribution of the brightness (light intensity) of the red illumination light and the green illumination light is uniform. As shown in FIG. 9B, the light intensity of the red illumination light and the green illumination light at the position Pf is BR27. The light intensity BR27 of the red illumination light and the green illumination light at the position Pf corresponds to the light intensity BR7 of the red illumination light and the green illumination light at the position Pb.

  The phase difference plate 103 converts blue illumination light, which is linearly polarized light, into circularly polarized light. The phase difference plate 103 converts the blue illumination light into circularly polarized light, so that the s-polarized light and the p-polarized light in the blue illumination light have the same brightness (light intensity) distribution as shown in FIGS. 11A and 12A. be able to.

  In the s-polarized light and p-polarized light in the blue illumination light, the region corresponding to the total reflection region 220T is darker than the red illumination light and the green illumination light, and the region corresponding to the specific polarization reflection region 220R is the total reflection region. The distribution of brightness (light intensity) is much darker than the region corresponding to 220T.

  That is, as shown in FIG. 11B, the s-polarized light in the blue illumination light has a light intensity BR28 (BR28 <BR27) smaller than the light intensity BR27 of the red illumination light and the green illumination light in the region corresponding to the total reflection region 220T. The region corresponding to the specific polarization reflection region 220R has a light intensity BR29 (BR29 <BR28) smaller than the light intensity BR28 of the region corresponding to the total reflection region 220T. The s-polarized light intensities BR28 and BR29 of the blue illumination light at the position Pf correspond to the s-polarized light intensities BR8 and BR9 of the blue illumination light at the position Pb.

  As shown in FIG. 12B, the p-polarized light in the blue illumination light has a light intensity BR30 (BR30 <BR27) smaller than the light intensity BR27 of the red illumination light and the green illumination light in the region corresponding to the total reflection region 220T. In the region corresponding to the specific polarization reflection region 220R, the light intensity BR31 (BR31 <BR30) is smaller than the light intensity BR30 in the region corresponding to the total reflection region 220T. The p-polarized light intensities BR30 and BR31 of the blue illumination light at the position Pf correspond to the p-polarized light intensities BR10 and BR11 of the blue illumination light at the position Pb.

  Accordingly, the blue illumination light including the s-polarized light having the brightness (light intensity) distribution shown in FIGS. 11A and 11B and the p-polarized light having the brightness (light intensity) distribution shown in FIGS. 12A and 12B is shown in FIG. As shown in FIG. 10A, the region corresponding to the total reflection region 220T has the same brightness as the red illumination light and the green illumination light, and the region corresponding to the specific polarization reflection region 220R is the red illumination light and the green light. The brightness (light intensity) distribution is darker than the illumination light.

  That is, as shown in FIG. 10B, the blue illumination light has the same light intensity BR32 (BR32 = BR27) as the light intensity BR27 of the red illumination light and the green illumination light in the region corresponding to the total reflection region 220T. The region corresponding to the specific polarization reflection region 220R has a light intensity BR33 (BR33 <BR32) smaller than the light intensity BR32 of the region corresponding to the total reflection region 220T. A difference between the light intensity BR32 and the light intensity BR33 of the blue illumination light at the position Pf is defined as a light intensity difference BRDf.

  The light intensities BR32 and BR33 of the blue illumination light at the position Pf correspond to the light intensities BR12 and BR13 of the blue illumination light at the position Pb. The light intensity difference BRDf of the blue illumination light at the position Pf corresponds to the light intensity difference BRDb of the blue illumination light at the position Pb.

  At the position Pf, it is preferable that the s-polarized light intensities BR28 and BR29 and the p-polarized light intensities BR30 and BR31 in the blue illumination light have the same value, respectively. The light intensity difference BRDe and the light intensity difference BRDf are substantially the same at the position Pe where the blue illumination light is reflected from the dichroic mirror 220 and the position Pf where the blue illumination light is transmitted through the phase difference plate 103.

  As shown in FIG. 3, the polarization conversion element 150 is arranged on the optical path of the blue illumination light and the yellow illumination light transmitted through the phase difference plate 103. Blue illumination light and yellow illumination light transmitted through the phase difference plate 103 are incident on the polarization conversion element 150 shown in FIGS. The specific polarization reflection region 220R of the dichroic mirror 220 and the phase difference plate 152 of the polarization conversion element 150 correspond to each other. In the second embodiment, the phase difference plate 152 is a second phase difference plate.

  14A, 14B, FIG. 15A, FIG. 15B, FIG. 16A, FIG. 16B, FIG. 17A, and FIG. 17B, the blue illumination light and the blue light at the position Pg through which the yellow illumination light is transmitted through the polarization conversion element 150 are used. The brightness distribution of the red illumination light and the green illumination light included in the illumination light and the yellow illumination light will be described. The position Pg corresponds to the position of the illumination pupil. 14A, 14B, 15A, 15B, 16A, 16B, 17A, and 17B are illustrated in FIGS. 9A, 9B, 10A, 10B, 11A, 11B, 12A, and 12A. Each corresponds to FIG. 12B.

  The position Pg shown in FIG. 18 corresponds to the position Pc shown in FIG. The region corresponding to the specific polarization reflection region 220R at the position Pg corresponds to the region corresponding to the specific polarization reflection region 120R at the position Pc. The region corresponding to the total reflection region 220T at the position Pg corresponds to the region corresponding to the transmission region 120T at the position Pc.

  The yellow illumination light is aligned with the p-polarized light by the polarization conversion element 150. In the illumination pupil (position Pg), as shown in FIG. 14A, the distribution of the brightness (light intensity) of the red illumination light and the green illumination light is uniform. As shown in FIG. 14B, the light intensity of the red illumination light and the green illumination light at the illumination pupil is BR34. The light intensity BR34 of the red illumination light and the green illumination light at the position Pg corresponds to the light intensity BR14 of the red illumination light and the green illumination light at the position Pc.

  As shown in FIG. 13, the polarization conversion element 150 transmits p-polarized light. As shown in FIG. 17A, the p-polarized light in the blue illumination light incident on the polarization conversion element 150 has a region corresponding to the total reflection region 220T that is darker than the red illumination light and the green illumination light, and a specific polarization reflection region. The region corresponding to 220R has a darker brightness (light intensity) distribution than the region corresponding to the total reflection region 220T and passes through the polarization conversion element 150.

  That is, the p-polarized light in the blue illumination light incident on the polarization conversion element 150 is light that is smaller than the light intensity BR34 of the red illumination light and the green illumination light in the region corresponding to the total reflection region 220T, as shown in FIG. 17B. Polarization conversion has an intensity BR39 (BR39 <BR34) and a light intensity BR40 (BR40 <BR39) that is smaller than the light intensity BR39 in the area corresponding to the total reflection area 220T in the area corresponding to the specific polarization reflection area 220R. The element 150 is transmitted. The p-polarized light intensities BR39 and BR40 of the blue illumination light at the position Pg correspond to the p-polarized light intensities BR19 and BR20 of the blue illumination light at the position Pc.

  As shown in FIG. 13, the polarization conversion element 150 shifts the optical axis of the s-polarized light in the reflection direction by reflecting the s-polarized light incident on the polarization conversion element 150 in the polarization beam splitter 151. The polarization conversion element 150 converts the s-polarized light into p-polarized light by the phase difference plate 152. Accordingly, the blue illumination light is aligned with the p-polarized light by the polarization conversion element 150.

  As shown in FIGS. 16A and 16B, the s-polarized light in the blue illumination light incident on the polarization conversion element 150 has the brightness (light intensity) distribution shown in FIGS. 11A and 11B shifted in the reflection direction by the polarization conversion element 150. The light is emitted from the polarization conversion element 150 as p-polarized blue illumination light having a distribution of brightness (light intensity).

  In the s-polarized light in the blue illumination light incident on the polarization conversion element 150, the region corresponding to the total reflection region 220T is darker than the red illumination light and the green illumination light, and the region corresponding to the specific polarization reflection region 220R is all. The light is emitted from the polarization conversion element 150 as p-polarized blue illumination light having a distribution of brightness (light intensity) darker than the region corresponding to the reflection region 220T.

  That is, as shown in FIG. 16B, the s-polarized light in the blue illumination light incident on the polarization conversion element 150 is light smaller than the light intensity BR34 of the red illumination light and the green illumination light in the region corresponding to the total reflection region 220T. P-polarized blue light having an intensity BR37 (BR37 <BR34) and having a light intensity BR38 (BR38 <BR37) that is smaller than the light intensity BR37 in the area corresponding to the total reflection area 220T in the area corresponding to the specific polarization reflection area 220R. Illumination light is emitted from the polarization conversion element 150.

  The p-polarized light intensities BR37 and BR38 of the blue illumination light at the position Pg corresponding to the s-polarization of the blue illumination light at the position Pf are the p-polarizations of the blue illumination light at the position Pc corresponding to the s-polarization of the blue illumination light at the position Pb. Correspond to the light intensities BR17 and BR18.

  Therefore, as shown in FIG. 15A, the blue illumination light that is aligned with the p-polarized light by the polarization conversion element 150 has the same brightness as the red illumination light and the green illumination light in the region corresponding to the total reflection region 220T. In addition, the region corresponding to the specific polarization reflection region 220R has a distribution of brightness (light intensity) that is darker than red illumination light and green illumination light.

  That is, as shown in FIG. 15B, the blue illumination light emitted from the polarization conversion element 150 has the same light intensity BR35 (the same as the light intensity BR34 of the red illumination light and the green illumination light in the region corresponding to the total reflection region 220T. BR35 = BR34), and the region corresponding to the specific polarization reflection region 220R has a light intensity BR36 (BR36 <BR35) smaller than the light intensity BR35 of the region corresponding to the total reflection region 220T. A difference between the light intensity BR35 and the light intensity BR36 of the blue illumination light at the illumination pupil (position Pg) is defined as a light intensity difference BRDg.

  The light intensities BR35 and BR36 of the blue illumination light at the position Pg correspond to the light intensities BR15 and BR16 of the blue illumination light at the position Pc. The light intensity difference BRDg of the blue illumination light at the position Pg corresponds to the light intensity difference BRDc of the blue illumination light at the position Pc.

  In the projector 200 and the multi-projection system 1 using the projector 200, the blue illumination light emitted from the plurality of blue laser elements BL constituting the light source 101 is converted from linearly polarized light into circularly polarized light by the phase difference plate 103, and further polarization conversion is performed. The element 150 transmits the p-polarized light in the blue illumination light and shifts the optical axis of the s-polarized light.

  Therefore, according to the projector 200 and the multi-projection system 1, the light intensity difference BRDg of the blue illumination light at the illumination pupil (position Pg) is made smaller than the light intensity differences BRDe and BRDf of the blue illumination light at the positions Pe and Pf. Therefore, variation in the brightness of the blue illumination light can be reduced.

  As shown in FIG. 18, the blue illumination light and the yellow illumination light aligned with the P-polarized light by the polarization conversion element 150 are irradiated to the dichroic mirror 105 through the lens 134. The dichroic mirror 105 separates incident blue illumination light and yellow illumination light.

  The yellow illumination light YLL separated by the dichroic mirror 105 is reflected by the reflection mirror 142 and irradiated on the dichroic mirror 106. The dichroic mirror 106 separates the yellow illumination light YLL into a red illumination light RLL including a red band component and a green illumination light GLL including a green band component.

  The red illumination light RLL separated by the dichroic mirror 106 is applied to the reflective polarizing plate 107R through the lens 135. The green illumination light GLL separated by the dichroic mirror 106 is applied to the reflective polarizing plate 107G through the lens 136. The blue illumination light BLL separated by the dichroic mirror 105 is reflected by the reflection mirror 143 and irradiated to the reflective polarizing plate 107B through the lens 137.

  The reflective polarizing plates 107R, 107G, and 107B reflect either the s-polarized light or the p-polarized light and transmit the other. FIG. 18 shows a state in which the reflective polarizing plates 107R, 107G, and 107B reflect s-polarized light and transmit p-polarized light. The p-polarized red illumination light RLL, green illumination light GLL, and blue illumination light BLL are respectively transmitted through the reflective polarizing plates 107R, 107G, and 107B, and are respectively transmitted to the image display elements 108R, 108G, and 108B. Irradiated.

  The image display element 108R modulates the red illumination light RLL based on the image data of the red component, and generates s-polarized red image light RML. The image display element 108G modulates the green illumination light GLL based on the image data of the green component, and generates s-polarized green image light GML. The image display element 108B optically modulates the blue illumination light BLL based on the blue component image data to generate s-polarized blue image light BML.

  The red image light RML, the green image light GML, and the blue image light BML generated by the image display elements 108R, 108G, and 108B are reflected by the reflective polarizing plates 107R, 107G, and 107B, respectively, and color synthesis is performed. Irradiated to the prism 109. The color combining prism 109 combines the red image light RML, the green image light GML, and the blue image light BML by reflecting the red image light RML and the blue image light BML and transmitting the green image light GML.

  The red image light RML, the green image light GML, and the blue image light BML synthesized by the color synthesis prism 109 are projected onto the screen SRN and the like via the aperture 110 and the projection lens 111 as shown in FIG. 1 or FIG. Is done. As a result, the projector 200 displays a full-color image IM obtained by combining the red image light RML, the green image light GML, and the blue image light BML on the screen SRN or the like.

  As shown in FIG. 18, the position Ph of the diaphragm 110 corresponds to the position of the projection pupil. The position Ph shown in FIG. 18 corresponds to the position Pd shown in FIG. The illumination pupil and the projection pupil have a conjugate relationship. Accordingly, the brightness distribution of the red image light RML, the green image light GML, and the blue image light BML at the position Ph corresponding to the position of the projection pupil is the red illumination light RLL at the position Pg corresponding to the position of the illumination pupil. This corresponds to the brightness distribution of the green illumination light GLL and the blue illumination light BLL.

  A state in which the phase difference plate 103 is not disposed is taken as a comparative example. In the comparative example, the brightness distributions of the red image light RML, the green image light GML, and the blue image light BML at the position Ph corresponding to the position of the projection pupil are the red illumination light RLL, the green illumination light GLL at the position Pe, This corresponds to the brightness distribution of the blue illumination light BLL.

  Therefore, according to the projector 200 and the multi-projection system 1, the blue illumination light BLL is converted into circularly polarized light by the phase difference plate 103, and further the s-polarized light axis of the blue illumination light is shifted by the polarization conversion element 150. As compared with the comparative example, it is possible to reduce the variation in the brightness of the blue image light BLL in the projection pupil.

  Therefore, according to the projector 200 and the multi-projection system 1, it is possible to reduce the color distribution caused by the light shielding plate 10 by reducing the variation in the brightness of the blue image light BLL in the projection pupil. According to the projector 200 and the multi-projection system 1, when the projector 200 includes a plurality of blue laser elements BL and phosphors 102 that are illumination light sources, deterioration of the quality of the multi-projection image can be suppressed.

  In addition, this invention is not limited to embodiment mentioned above, In the range which does not deviate from the summary of this invention, it can change variously.

  In the projectors 100 and 200 according to the first and second embodiments, as illustrated in FIG. 13, the polarization conversion element 150 has the retardation plate 152 disposed on the optical path of s-polarized light. As shown in FIG. 24, in the polarization conversion element 150, the phase difference plate 152 may be arranged on the optical path of p-polarized light instead of s-polarized light.

  In this case, the polarization conversion element 150 shifts the optical axis of the s-polarized light in the reflection direction by reflecting the s-polarized light incident on the polarization conversion element 150 in the polarization beam splitter 151. The polarization conversion element 150 converts p-polarized light into s-polarized light by the phase difference plate 152. Therefore, the blue illumination light and the yellow illumination light emitted from the polarization conversion element 150 are aligned with the s-polarized light by the polarization conversion element 150.

  In the projectors 100 and 200 according to the first and second embodiments, as shown in FIGS. 3 and 18, the dichroic mirrors 120 and 220 include specific polarization reflection regions 120R and 220R, transmission regions 120T, and total reflection regions 220T. They are arranged so that the longitudinal direction is the front-rear direction of the page. In the polarization conversion element 150, the polarization beam splitter 151 shifts the optical axis of the s-polarized light in the left-right direction on the paper surface in correspondence with the dichroic mirrors 120 and 220. It is arranged so that the direction is the front and back direction of the page.

  The dichroic mirrors 120 and 220 may be arranged such that the longitudinal directions of the specific polarization reflection regions 120R and 220R, the transmission region 120T, and the total reflection region 220T are the vertical direction of the paper surface. Specifically, the dichroic mirror 120 may be arranged so as to be rotated 90 degrees clockwise or counterclockwise with respect to the state shown in FIG. 4A. The dichroic mirror 220 may be arranged so as to be rotated 90 degrees clockwise or counterclockwise with respect to the state shown in FIG. 19A.

  The polarization conversion element 150 corresponds to the dichroic mirrors 120 and 220, the polarization beam splitter 151 shifts the optical axis of s-polarized light toward the front side of the paper surface, and the longitudinal direction of the phase difference plate 152 is the horizontal direction of the paper surface. It is arranged to be.

  In this case, as shown in FIG. 25, the polarization conversion element 150 reflects the p-polarized light incident on the polarization conversion element 150 in the polarization beam splitter 151, thereby shifting the optical axis of the p-polarization in the reflection direction. Further, the polarization conversion element 150 converts p-polarized light into s-polarized light by the phase difference plate 152. The polarization conversion element 150 transmits the s-polarized light incident on the polarization conversion element 150.

  Therefore, the blue illumination light and the yellow illumination light emitted from the polarization conversion element 150 are aligned with the s-polarized light by the polarization conversion element 150. In addition, each component subsequent to the polarization conversion element 150 has reverse characteristics with respect to the s-polarization and the p-polarization when the blue illumination light and the yellow illumination light are aligned with the p-polarization by the polarization conversion element 150. Become.

  24 and FIG. 25, that is, in the polarization conversion element 150, the polarization beam splitter 151 shifts the optical axis of the s-polarized light toward the front side of the paper with respect to the state shown in FIG. The phase difference plate 152 may be arranged so that the longitudinal direction thereof is the left-right direction of the paper surface, and the phase difference plate 152 may be arranged on the optical path of p-polarized light instead of s-polarized light.

  The dichroic mirrors 120 and 220 are arranged so that the longitudinal directions of the specific polarization reflection regions 120R and 220R, the transmission region 120T, and the total reflection region 220T are in the vertical direction of the drawing with respect to the state shown in FIGS. Is done.

  In this case, the polarization conversion element 150 shifts the optical axis of the p-polarized light in the reflection direction by reflecting the p-polarized light incident on the polarization conversion element 150 in the polarization beam splitter 151. The polarization conversion element 150 converts the s-polarized light incident on the polarization conversion element 150 into p-polarized light by the phase difference plate 152. Therefore, the blue illumination light and the yellow illumination light emitted from the polarization conversion element 150 are aligned with the p-polarized light by the polarization conversion element 150.

  In the projector 100 of this embodiment, the light source 101 (blue laser element BL) is configured to emit s-polarized blue laser light, but may be configured to emit p-polarized blue laser light. In that case, the characteristics of each component with respect to s-polarized light and p-polarized light are reversed.

  For example, the dichroic mirror 120 is arranged such that the polarization direction of the blue laser light is p-polarized with respect to the dichroic mirror 120, and has the optical characteristics of reflecting the p-polarized light and transmitting the s-polarized light with respect to the blue laser light. . In this case, the p-polarized light is the first linearly polarized light, and the s-polarized light is the second linearly polarized light.

  In the projector 200 of this embodiment, the light source 101 (blue laser element BL) is configured to emit p-polarized blue laser light, but may be configured to emit s-polarized blue laser light. In that case, the characteristics of each component with respect to p-polarized light and s-polarized light are reversed.

  For example, the dichroic mirror 220 is arranged such that the polarization direction of the blue laser light is p-polarized with respect to the dichroic mirror 220, and has an optical characteristic of reflecting p-polarized light and transmitting s-polarized light with respect to the blue laser light. . In this case, the p-polarized light is the first linearly polarized light, and the s-polarized light is the second linearly polarized light.

1 Multi-Projection System 10, 10a, 10b Light-shielding plate PJ, PJa, PJb, 100, 200 Projector 101 Light source (first illumination light source)
102 phosphor (second illumination light source)
103 Retardation plate 105 Dichroic mirror (second dichroic mirror)
106 Dichroic mirror (third dichroic mirror)
120,220 Dichroic mirror (first dichroic mirror)
150 Polarization conversion element IM, IMa, IMb image MPIM Multi-projection image

Claims (4)

The first illumination light source that emits the first illumination light that is the second polarized light when one of the s-polarized light and the p-polarized light that is linearly polarized light is the first polarized light and the other is the second polarized light. When,
A second illumination light source that emits second illumination light;
A specific polarization reflection region that is disposed on an optical path of the first and second illumination lights, transmits the second polarization, and reflects the first polarization and the second illumination light; and A first dichroic mirror having a total reflection region that reflects the first and second illumination light;
A phase difference plate disposed on the optical path of the first and second illumination light reflected by the first dichroic mirror and converting the linearly polarized light into circularly polarized light;
It is disposed on the optical path of the first and second illumination light that has passed through the phase difference plate, transmits one of the first polarized light and the second polarized light, and transmits the other polarized light. A polarization conversion element that shifts an optical axis and aligns the first and second illumination lights with the first polarized light or the second polarized light;
A projector comprising: The first illumination light source is a blue laser light source;
The first illumination light is blue laser light;
The second illumination light source is a phosphor;
The second illumination light is yellow illumination light including a red band component and a green band component generated by irradiating the phosphor with the blue laser light,
The phosphor diffuses the blue laser light into random polarization mixed with a plurality of polarized lights, and irradiates the first dichroic mirror with the yellow illumination light and the blue laser light with the random polarization.
The projector according to claim 1. A second dichroic mirror that is disposed on the optical path of the first and second illumination light that has passed through the polarization conversion element and separates the yellow illumination light and the blue illumination light that is the blue laser light;
The yellow illumination light is disposed on the optical path of the yellow illumination light separated by the second dichroic mirror, and the yellow illumination light is separated into red illumination light including the red band component and green illumination light including the green band component. A third dichroic mirror that
The projector according to claim 2, further comprising: The projector according to any one of claims 1 to 3, which projects an image;
A light-shielding plate disposed corresponding to the projector so as to shield a part of the area of the image;
With multiple
A multi-projection system that displays a plurality of images projected by the plurality of projectors as a multi-projection image by overlapping the partial areas.