Illumination device and projector

Abstract

To prevent a reduction in image quality in a projector.SOLUTION: An illumination device of the present invention comprises: a light source that emits light; a collimating element that collimates the light emitted from the light source; a first lens array on which the light collimated by the collimating element is incident and that includes a plurality of first small lenses; a second lens array on which light emitted from the first lens array is incident and that includes a plurality of second small lenses; and a condensation element that condenses light emitted from the second lens array toward an illumination area. The rays of light emitted from at least two first small lenses are incident on one second small lens. Focal planes of the plurality of second small lenses are located, in an optical path through which the light travels, on the front stage of a virtual surface including a plurality of contacts of the first small lenses adjacent to each other in the first lens array.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an illumination device and a projector. [Background technology]

[0002] In a display device such as a projector that projects an image or video onto a projection surface such as a screen, area division illumination may be performed. In area division illumination, for example, light emitted from a light source is divided into a plurality of partial light beams within a plane intersecting the optical axis, and the plurality of partial light beams are irradiated onto an illumination area of ​​a light modulation device arranged downstream of the light source.

[0003] For example, the illumination device of the projector disclosed in Patent Document 1 has a first lens array that divides the light emitted from the optical device into a plurality of partial light beams, and a second lens array that contributes to irradiating the light emitted from the first lens array to the image forming area of ​​the light modulation device with a uniform illuminance distribution. In the illumination device disclosed in Patent Document 1, the focal plane of the second lens array arranged in a stage subsequent to the first lens array is located on the emission surface side rather than the incidence surface of the first lens array. In the projector disclosed in Patent Document 1, in the illumination area corresponding to the light incidence area of ​​the wavelength conversion element, areas that are not irradiated with light, including the center, are provided in a lattice shape. This allows heat to escape easily in the areas that are not irradiated with light, reducing the temperature difference in the illumination area and suppressing the decrease in light utilization efficiency. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2022-034731 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the lighting device disclosed in Patent Document 1, the illuminance of the area in the illumination area where light is not irradiated is lower than the illuminance of the surroundings. When such area division lighting is applied to the image formation area of ​​the light modulation device of the projector as the illumination area, areas where light is not irradiated and where the light intensity and illuminance are low are generated in a lattice pattern between the areas in the image formation area of ​​the light modulation device that are illuminated by each of the multiple partial light beams. It is difficult to restore the illuminance that has already decreased in the image formation area of ​​the light modulation device in the optical path along which the light travels, and there are cases where the lattice-shaped dark areas stand out in the projected image, degrading the image quality, so improvement was desired. [Means for solving the problem]

[0006] An illumination device according to one embodiment of the present invention includes a light source that emits light, a collimating element that collimates the light emitted from the light source, a first lens array that receives the light collimated by the collimating element and includes a plurality of first small lenses, a second lens array that receives the light emitted from the first lens array and includes a plurality of second small lenses, and a focusing element that focuses the light emitted from the second lens array toward an illumination area. Each of the lights emitted from at least two first small lenses is incident on one second small lens, and focal planes of the second small lenses are located in front of a virtual plane that includes a plurality of contact points between adjacent first small lenses in the first lens array in the optical path along which the light travels. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of a projector according to a first embodiment. [Diagram 2] FIG. 2 is a schematic diagram of an illumination device of the projector of FIG. [Diagram 3] FIG. 2 is a schematic diagram of a main part of the projector in FIG. [Figure 4] 2 is a schematic diagram of a part of an entrance surface of a light modulation device of the projector of FIG. 1. [Diagram 5] 2 is another schematic diagram of a portion of the entrance surface of the light modulation device of the projector of FIG. 1. [Figure 6]2 is a schematic diagram for explaining the principle of correcting the light intensity of an illumination area in the projector of FIG. 1. FIG. [Figure 7] 11A and 11B are schematic diagrams for explaining the principle of correcting the light intensity of an illumination area in a projector of a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each drawing, the scale of the dimensions of some components may be changed in order to make each component easier to see.

[0009] First, a projector according to an embodiment of the present invention will be described with reference to Fig. 1. Fig. 1 is a schematic diagram showing the configuration of a projector 1 according to an embodiment of the present invention. The projector 1 is a projection-type display device that displays an image or video on a screen SCR. The projector 1 includes an illumination device 2, a color separation optical system 3, light modulation devices 4R, 4G, and 4B, a color synthesis optical system 5, a projection optical system 6, a control device 110, and an imaging device 120. The projector 1 is a three-plate projector having three light modulation devices.

[0010] The lighting device 2 emits white light WL toward the color separation optical system 3. The white light WL is illumination light in the projector 1, and contains red light RL, green light GL, and blue light BL. The configuration of the lighting device 2 will be described later.

[0011] The color separation optical system 3 separates the white light WL into red light RL, green light GL, and blue light BL. The color separation optical system 3 includes, for example, a first dichroic mirror 11, a second dichroic mirror 12, a first total reflection mirror 13, a second total reflection mirror 14, a third total reflection mirror 15, a first relay lens 16, and a second relay lens 17.

[0012] The first dichroic mirror 11 is disposed on the optical path of the white light WL emitted from the lighting device 2, and separates the incident white light WL into red light RL, green light GL, and blue light BL. The first dichroic mirror 11 transmits the red light RL and reflects the green light GL and blue light BL. The second dichroic mirror 12 is disposed on the common optical path of the green light GL and blue light BL emitted from the first dichroic mirror 11, and separates the green light GL from the blue light BL. The second dichroic mirror 12 transmits the blue light BL and reflects the green light GL.

[0013] The first total reflection mirror 13 reflects the red light RL toward the light modulation device 4R. The second total reflection mirror 14 and the third total reflection mirror 15 guide the blue light BL to the light modulation device 4B. The green light GL is reflected from the second dichroic mirror 12 toward the light modulation device 4G. The red light RL, green light GL, and blue light BL contained in the white light WL correspond to the light emitted from the illumination device 2.

[0014] The first relay lens 16 is disposed on the optical path of the blue light BL between the second dichroic mirror 12 and the second total reflection mirror 14. The second relay lens 17 is disposed on the optical path of the blue light BL between the second total reflection mirror 14 and the third total reflection mirror 15. The optical path length of the blue light BL from the first dichroic mirror 11 to the optical modulation device 4B is longer than the optical path length of the red light RL from the first dichroic mirror 11 to the optical modulation device 4R and the optical path length of the green light GL from the first dichroic mirror 11 to the optical modulation device 4G. Therefore, if a relay lens is not disposed on the optical path of the blue light BL, the optical loss of the blue light BL is larger than the optical losses of the red light RL and the green light GL. By disposing the first relay lens 16 and the second relay lens 17 as described above, the optical loss of the blue light BL is compensated.

[0015] The light modulation device 4R is disposed on the optical path of the red light RL reflected by the first total reflection mirror 13 and emitted from the first total reflection mirror 13. The light modulation device 4R modulates the incident red light RL according to image information input from an image input device (not shown), forms red image light, and emits the red image light. The light modulation device 4G is disposed on the optical path of the green light GL reflected by the second dichroic mirror 12 and emitted from the second dichroic mirror 12. The light modulation device 4G modulates the incident green light GL according to image information input from an image input device (not shown), forms green image light, and emits the green image light. The light modulation device 4B is disposed on the optical path of the blue light BL reflected by the third total reflection mirror 15 and emitted from the third total reflection mirror 15. The light modulation device 4B modulates the incident blue light BL according to image information input from an image input device (not shown), forms blue image light, and emits blue image light. The image input device may be, for example, a personal computer or a portable terminal device.

[0016] Each of the light modulation devices 4R, 4G, and 4B uses, for example, a transmissive liquid crystal panel. A polarizing plate (not shown) is disposed on each of the entrance side and exit side of the liquid crystal panel. A field lens 10R is disposed on the optical path of the red light RL between the first total reflection mirror 13 and the light modulation device 4R. A field lens 10G is disposed on the optical path of the green light GL between the second dichroic mirror 12 and the light modulation device 4G. A field lens 10B is disposed on the optical path of the blue light BL between the third total reflection mirror 15 and the light modulation device 4B.

[0017] The color synthesis optical system 5 is disposed across the optical path of the red image light emitted from the light modulation device 4R, the optical path of the green image light emitted from the light modulation device 4G, and the optical path of the blue image light emitted from the light modulation device 4B. When viewed from the top or side as shown in FIG. 1, the synthesis position of the color light in the color synthesis optical system 5 overlaps with the intersection of the optical path of the red image light, the optical path of the green image light, and the optical path of the blue image light. In the color synthesis optical system 5, the red image light, the green image light, and the blue image light are synthesized with each other to form color image light. The color synthesis optical system 5 emits color image light. For example, a cross dichroic prism is used for the color synthesis optical system 5.

[0018] The projection optical system 6 is disposed on the optical path of the color image light emitted from the color synthesis optical system 5. The color image light emitted from the color synthesis optical system 5 corresponds to the light modulated by the light modulation devices 4R, 4G, and 4B. The projection optical system 6 enlarges and projects the color image light emitted from and incident on the color synthesis optical system 5 toward the screen SCR. The color image light enlarged and projected from the projection optical system 6 is displayed as a color image on a display surface of the screen SCR facing the emission surface of the projection optical system 6.

[0019] The projection optical system 6 is composed of, for example, a plurality of optical lenses, but may be composed of a single optical lens. The optical lens includes various lenses, such as a plano-convex lens, a biconvex lens, a meniscus lens, an aspheric lens, a rod lens, and a free curved lens.

[0020] The control device 110 is electrically connected to the liquid crystal panels of each of the light modulation devices 4R, 4G, and 4B. The control device 110 is configured by a computer or integrated circuit in which the processing of each driving device that drives the imaging device 120, the light source 21, and each of the light modulation devices 4R, 4G, and 4B is built in as a program, and is configured by, for example, a processor. The control device 110 receives image data of the projection target from an image input device such as a computer (not shown), can change the luminance data of each pixel of the liquid crystal panel of each of the light modulation devices 4R, 4G, and 4B, and controls the luminance information of the liquid crystal panel. The control device 110 may be housed in the internal space of the exterior body of the projector 1, like the illumination device 2, the color separation optical system 3, the light modulation devices 4R, 4G, and 4B, the color synthesis optical system 5, and the projection optical system 6, or may be arranged outside the exterior body and be capable of communicating with the light modulation devices 4R, 4G, and 4B.

[0021] The imaging device 120 captures a projection image including image light projected by the projection optical system 6 in real time. The imaging device 120 is configured, for example, with a small imaging camera. The imaging device 120 is disposed so as not to block the image light emitted from the projection optical system 6, and is disposed, for example, on a surface of the exterior body of the projector 1 opposite to a surface facing the installation surface of the projector 1. The imaging surface of the imaging device 120 faces the screen SCR. Image data captured by the imaging device 120 and the imaging result are transmitted directly or indirectly to the control device 110.

[0022] Next, an illumination device according to an embodiment of the present invention will be described with reference to Fig. 2 to Fig. 4. Fig. 2 is a schematic diagram showing the configuration of an illumination device 2 according to an embodiment of the present invention. The illumination device 2 includes a light source 21, a collimating element 22, an afocal optical system 23, a first retardation plate 281, a wavelength conversion element 40, a polarization separation element 25, a first focusing optical system 26, a second retardation plate 282, a second focusing optical system 29, a diffuse reflection element 30, an integrating optical system 31, a polarization conversion element 32, and a superimposing lens 33.

[0023] 2, using a Cartesian coordinate system, the axis along the principal ray of the blue light BL emitted from the light source 21 is defined as the optical axis AX1, and the axis parallel to the optical axis AX1 is defined as the X-axis. The axis along the principal ray of the yellow light YL emitted from the wavelength conversion element 40 is defined as the optical axis AX2, and the axis parallel to the optical axis AX2 is defined as the Y-axis. The axis perpendicular to the X-axis and Y-axis is defined as the Z-axis.

[0024] The light source 21, the collimating element 22, the afocal optical system 23, the first retardation plate 281, the polarization separation element 25, the second retardation plate 282, the second focusing optical system 29, and the diffuse reflection element 30 are arranged in sequence on the optical axis AX1. The wavelength conversion element 40, the first focusing optical system 26, the polarization separation element 25, the integrated optical system 31, the polarization conversion element 32, and the superimposing lens 33 are arranged in sequence on the optical axis AX2. The optical axes AX1 and AX2 are in the same plane and are perpendicular to each other.

[0025] The light source 21 emits blue light BL. The blue light BL is colored light constituting the white light WL emitted from the lighting device 2, and is also excitation light irradiated to the wavelength conversion element 40. In this embodiment, the light source 21 has one light emitting element 211 that emits blue light BL. The light emitting element 211 is a semiconductor laser element that emits blue light BL. The semiconductor laser element emits blue light having a wavelength band that at least belongs to blue in the visible wavelength band. The peak wavelength of the blue light BL is, for example, 460 nm. The blue light BL corresponds to the "light" emitted by the light source 21.

[0026] The light source 21 may include a plurality of light-emitting elements 211. For example, the plurality of light-emitting elements 211 may be arranged in an array in a plane perpendicular to the optical axis AX1. For example, four light source units, each having four light-emitting elements 211 arranged in a row along the Y axis, may be arranged in four sets along the Z axis. That is, the light source 21 may have 16 light-emitting elements 211 arranged in a matrix of four rows and four columns. The number and arrangement of the light-emitting elements 211 are not limited to the above configuration and may be changed as appropriate.

[0027] The blue light BL emitted from the light source 21 is incident on the collimating element 22. The collimating element 22 collimates the blue light BL emitted from the light source 21 and converts the blue light BL into substantially parallel light. The collimating element 22 has one collimating lens 221. The collimating lens 221 is, for example, a plano-convex lens having a flat surface perpendicular to the optical axis AX1 on the incident side and a convex curved surface on the exit side. The collimating element 22 is, for example, composed of a plano-convex lens, but may be an optical element having a collimating function other than a plano-convex lens, may be a biconvex lens, or may be composed of multiple optical lenses.

[0028] As described above, when the light source 21 has a plurality of light-emitting elements 211 arranged in a matrix in a plane perpendicular to the optical axis AX1, the collimator element 22 has a plurality of collimator lenses 221 arranged in a matrix in a plane perpendicular to the optical axis AX1 so as to correspond to the plurality of light-emitting elements 211. One collimator lens 221 is disposed at a position where the blue light BL emitted from one light-emitting element 211 is incident.

[0029] The blue light BL emitted from the collimating element 22 enters the afocal optical system 23. The afocal optical system 23 adjusts the beam diameter of the blue light BL. The afocal optical system 23 has, for example, a biconvex lens 231 and a plano-concave lens 232 arranged on the exit side of the biconvex lens 231.

[0030] The blue light BL emitted from the afocal optical system 23 enters the first retardation plate 281. The first retardation plate 281 is, for example, a half-wave plate that is rotatable around a rotation axis parallel to the optical axis AX1. The blue light BL immediately after being emitted from the light source 21 is linearly polarized light having a predetermined polarization direction. By appropriately setting the rotation angle of the first retardation plate 281, the linearly polarized blue light BL can be converted into blue light BL containing an S-polarized component and a P-polarized component at a predetermined ratio corresponding to the polarization separation element 25 after passing through the first retardation plate 281. By changing the rotation angle of the first retardation plate 281, the ratio of the S-polarized component and the P-polarized component can be adjusted.

[0031] The blue light BL, which is emitted from the first retardation plate 281 and contains an S-polarized component and a P-polarized component, enters the polarization separation element 25. The polarization separation element 25 is, for example, composed of a polarization beam splitter having wavelength selectivity, and is formed in a plate shape. A polarization separation film (not shown) is provided on the plate surface of the polarization separation element 25. The polarization separation element 25 is disposed so that the polarization separation film forms an angle of 45° with the optical axis AX1 and the optical axis AX2.

[0032] The polarization separation element 25 separates the incident blue light BL into blue light BLS, which is an S-polarized component relative to the polarization separation element 25, and blue light BLP, which is a P-polarized component. Specifically, the polarization separation element 25 reflects the blue light BLS, which is an S-polarized component, and guides it to the wavelength conversion element 40, and transmits the blue light BLP, which is a P-polarized component, and guides it to the diffuse reflection element 30. In addition to the function of polarizing and separating the blue light BL, the polarization separation element 25 has a color separation function of transmitting yellow light, which has a different wavelength band from the blue light BL, regardless of the polarization state.

[0033] The S-polarized blue light BLS reflected by the polarization separation element 25 enters the first focusing optical system 26. The first focusing optical system 26 focuses the blue light BLS emitted from the polarization separation element 25 toward the wavelength conversion element 40. The first focusing optical system 26 has a first lens 261 and a second lens 262. Each of the first lens 261 and the second lens 262 is, for example, a biconvex lens. The blue light BLS emitted from the first focusing optical system 26 enters the wavelength conversion element 40 while being focused along the optical axis AX2.

[0034] The wavelength conversion element 40 includes a substrate 41, a wavelength conversion layer 42, and a heat sink 44. The wavelength conversion layer 42 is bonded to a first surface 41a of the substrate 41 by a bonding material (not shown). For example, a nano-silver sintered metal material is used as the bonding material. The substrate 41 is made of a metal material having high light reflectance, such as aluminum or silver. The first surface 41a of the substrate 41 reflects light traveling inside the wavelength conversion layer 42. A reflective layer (not shown) may be provided between the substrate 41 and the wavelength conversion layer 42.

[0035] The wavelength conversion layer 42 is made of a phosphor. In this embodiment, a fixed type wavelength conversion element is used as the wavelength conversion element 40. The fixed type wavelength conversion element does not have a driving source such as a motor and is not rotatable. The blue light BLS focused by the first lens 261 and the second lens 262 is incident on the wavelength conversion element 40.

[0036] The wavelength conversion layer 42 includes a ceramic phosphor that converts the blue light BLS into yellow light YL, which is fluorescent light. The yellow light YL has a wavelength band different from at least the blue light BL, BLS, and has a wavelength band of, for example, 490 to 750 nm. The yellow light YL includes green light and red light. The wavelength conversion layer 42 includes, for example, an yttrium-aluminum-garnet (YAG) phosphor. An example of a YAG phosphor is YAG:Ce, which contains cerium (Ce) as an activator. For YAG:Ce, a material obtained by mixing raw material powders containing constituent elements such as Y2O3, Al2O3, and CeO3 and causing a solid-phase reaction, Y-Al-O amorphous particles obtained by a wet method such as a coprecipitation method or a sol-gel method, or YAG particles obtained by a gas-phase method such as a spray drying method, a flame pyrolysis method, or a thermal plasma method is used. The wavelength conversion layer 42 may include scattering elements, such as a plurality of bubbles. The inclusion of scattering elements in the wavelength conversion layer 42 increases the extraction efficiency of the yellow light YL.

[0037] The heat sink 44 is provided on a second surface 41b opposite to the first surface 41a of the base material 41. The heat sink 44 has a plurality of fins. The heat sink 44 is fixed to the base material 41 by, for example, metal bonding. In the wavelength conversion element 40, heat from the wavelength conversion layer 42 is released through the heat sink 44, so that thermal deterioration of the wavelength conversion layer 42 is suppressed.

[0038] The yellow light YL generated by the wavelength conversion element 40 is emitted along the optical axis AX2 in the opposite direction to the blue light BLS, and is approximately collimated by the first focusing optical system 26, and then enters the polarization separation element 25. As described above, the polarization separation element 25 has the property of transmitting yellow light regardless of the polarization state, so the yellow light YL transmits through the polarization separation element 25.

[0039] On the other hand, the P-polarized blue light BLP emitted from the polarization separation element 25 is incident on the second phase difference plate 282. The second phase difference plate 282 is disposed on the optical path of the blue light BLP between the polarization separation element 25 and the diffuse reflection element 30. The second phase difference plate 282 is formed of, for example, a quarter wavelength plate. The P-polarized blue light BLP emitted from the polarization separation element 25 is converted by the second phase difference plate 282 into, for example, right-handed circularly polarized blue light BLC1 about the optical axis AX1, and then is incident on the second light-collecting optical system 29.

[0040] The second light collecting optical system 29 has a first lens 291 and a second lens 292. Each of the first lens 291 and the second lens 292 is composed of a biconvex lens. The second light collecting optical system 29 is composed of, for example, two biconvex lenses, but may be an optical element having a light collecting function other than a biconvex lens, may be a plano-convex lens, or may be composed of one optical lens. The second light collecting optical system 29 causes the blue light BLC1 to enter the diffuse reflecting element 30 in a collected state.

[0041] The diffuse reflecting element 30 is disposed on the optical path of the blue light BLP emitted from the polarization separation element 25. The diffuse reflecting element 30 reflects the blue light BLC1 emitted from the second light collecting optical system 29, and also diffusely reflects the blue light BLC1 toward the polarization separation element 25. It is preferable that the diffuse reflecting element 30 reflects the blue light BLC1 with an angular distribution close to Lambertian diffusion around the optical axis AX1. It is preferable that the diffuse reflecting element 30 does not disturb the polarization state of the blue light BLC1.

[0042] The light diffusely reflected by the diffuse reflecting element 30 is referred to as blue light BLC2. In this embodiment, blue light BLC1 is diffusely reflected to obtain blue light BLC2 having a substantially uniform illuminance distribution. For example, blue light BLC1 that is clockwise circularly polarized about the optical axis AX1 is diffusely reflected by the diffuse reflecting element 30 and converted into blue light BLC2 that is counterclockwise circularly polarized about the optical axis AX1.

[0043] The blue light BLC2 is converted into a parallel light by the second light collecting optical system 29, and then enters the second retardation plate 282 again. The left-handed circularly polarized blue light BLC2 is converted into S-polarized blue light BLS1 by the second retardation plate 282. The S-polarized blue light BLS1 is reflected by the polarization separation element 25 towards the integrating optical system 31.

[0044] The blue light BLS1 is combined with the yellow light YL emitted from the polarization separation element 25 to generate white light WL. That is, the blue light BLS1 and the yellow light YL are emitted from the polarization separation element 25 in the same direction, and the blue light BLS1 and the yellow light YL are combined to generate white light WL.

[0045] White light WL, which is illumination light, is emitted toward the integrated optical system 31. The integrated optical system 31 has a first lens array 34A and a second lens array 34B. White light WL, which is emitted from the light source 21 and includes blue light BL that is collimated by the collimating element 22, is incident on the first lens array 34A. The first lens array 34A includes a plurality of first small lenses 131. The plurality of first small lenses 131 are arranged in a matrix in a plane perpendicular to the optical axis AX2. In this embodiment, the first small lenses 131 are plano-convex lenses having a convex curved surface on the incident side and a flat surface on the exit side. That is, each of the plurality of first small lenses 131 has a first lens surface 131r, which is a convex curved surface that protrudes toward the incident side. The first lens surface 131r corresponds to the first curved surface. The white light WL incident on the first lens array 34A is split into partial beams the same number as the first small lenses 131, and these are emitted from the first lens array 34A towards the second lens array 34B.

[0046] The second lens array 34B is disposed on the optical path of the plurality of partial beams of the white light WL emitted from the first lens array 34A. The plurality of partial beams of the white light WL emitted from the first lens array 34A are incident on the second lens array 34B. The plurality of partial beams of the white light WL correspond to the light emitted from the first lens array. The second lens array 34B includes a plurality of second small lenses 132. The plurality of second small lenses 132 are arranged in a matrix in a plane perpendicular to the optical axis AX2. In this embodiment, the second small lenses 132 are plano-convex lenses having a flat surface on the incident side and a convex curved surface on the exit side. That is, each of the plurality of second small lenses 132 has a second lens surface 132r that is a convex curved surface protruding toward the exit side. The second lens surface 132r corresponds to the second curved surface. The diameter of one second small lens 132 is an integer multiple of one first small lens 131, for example, approximately twice as large as one first small lens 131. When viewed along the optical axis AX2 and the Y axis, two first small lenses 131 overlap one second small lens 132.

[0047] The white light WL emitted from the integrated optical system 31 is incident on the polarization conversion element 32. The polarization conversion element 32 has a polarization separation film and a retardation plate, not shown. The polarization conversion element 32 converts the white light WL including the unpolarized yellow light YL into linearly polarized light that is incident on the light modulation devices 4R, 4G, and 4B. Specifically, the polarization conversion element 32 converts the white light WL into linearly polarized light having a polarization direction corresponding to the transmission axis of the entrance side polarizing plate of the light modulation devices 4R, 4G, and 4B.

[0048] The white light WL emitted from the polarization conversion element 32 is incident on the superimposing lens 33. The superimposing lens 33 cooperates with the integrating optical system 31 to uniformize the illuminance distribution of the white light WL in the image forming areas of the light modulation devices 4R, 4G, and 4B. The integrating optical system 31 and the superimposing lens 33 constitute a superimposing optical system. In this manner, the illumination device 2 generates the white light WL. The superimposing lens 33 corresponds to a focusing element. The white light WL emitted from the polarization conversion element 32 corresponds to the light emitted from the second lens array 34B. The image forming areas of the light modulation devices 4R, 4G, and 4B correspond to the illumination areas.

[0049] 3 is a schematic diagram of the main parts related to the area division illumination in the projector 1 of this embodiment. As shown in FIG. 3, the white light WL emitted from the collimating lens 221, which is the collimating element 22, and collimated passes through various optical elements (not shown) and enters the first small lenses 131 of the first lens array 34A. The white light WL that enters the first small lenses 131 is focused on the second small lenses 132 of the second lens array 34B by each of the first small lenses 131. The white light WL that is focused on the second small lenses 132 diverges again from the focusing position, is color-separated by the omitted color separation optical system 3, is refracted by the superimposing lens 33 and the field lenses 10R, 10G, and 10B, and is irradiated on the image forming area, i.e., the illumination area IRR, of the entrance surface 4a of the light modulation devices 4R, 4G, and 4B.

[0050] White light WL emitted from at least two first small lenses 131 is incident on one second small lens 132. In this embodiment, for example, the white light WL incident on four first small lenses 131 arranged adjacent to each other in two rows and two columns in a plane perpendicular to the optical axis AX2 is condensed on one common second small lens 132. In other words, white light WL emitted from two to four first small lenses 131 is incident on one second small lens 132.

[0051] The focal plane FPB of the second lens array 34B is disposed at least in the region of the incident side of the first lens array 34A on the optical path along which the white light WL travels and on the optical axis AX2, more specifically, it is disposed on the incident side of the reference plane MPB of the first lens array 34A, that is, in front of the reference plane MPB. The reference plane MPB is a virtual plane including a plurality of contact points CT between the first small lenses 131 adjacent to each other in the first lens array 34A, and is substantially perpendicular to the optical axis AX2.

[0052] As described above, the first small lenses 131 of the first lens array 34A split the white light WL incident on the first lens array 34A into partial white light beams WLG. Since the focal plane FPB is disposed on the white light WL incidence side of the reference plane MPB on the optical axis AX2, a portion of one of the white light beams WLG adjacent to each other in a plane perpendicular to the optical axis AX2 overlaps with the other white light beam WLG. The area where the adjacent white light beams WLG overlap in this way corresponds to the area shaded in FIG. 3.

[0053] Fig. 4 is a schematic diagram of the incident surface 4a of the light modulation devices 4R, 4G, and 4B, and is a diagram showing the image formation area of ​​the incident surface 4a when viewed from the front along the optical axis of the red light RL included in the white light WL. As shown in Fig. 4, the incident surface 4a of the light modulation devices 4R, 4G, and 4B corresponds to an illumination area IRR of the color light CL color-separated from the white light WL. In the illumination area IRR, for example, a plurality of pixels PX of each of the light modulation devices 4R, 4G, and 4B are provided.

[0054] As shown in FIG. 3 and FIG. 4, a part of the color light CL separated from the white light WL emitted from one first small lens 131A of the plurality of first small lenses 131 of the first lens array 34A and a part of the color light CL separated from the white light WL emitted from another first small lens 131B of the plurality of first small lenses 131 overlap in the illumination region IRR. When the illumination region IRR includes the image forming region of the light modulation device 4R that generates red image light, the color light CL is red light RL. When the illumination region IRR includes the image forming region of the light modulation device 4G that generates green image light, the color light CL is green light GL. When the illumination region IRR includes the image forming region of the light modulation device 4B that generates blue image light, the color light CL is blue light BL. The color light CL of the white light WL emitted from the first small lens 131A corresponds to the first illumination light. The color light CL of the white light WL emitted from the first small lens 131B corresponds to the second illumination light.

[0055] As shown in FIG. 4, the region P1 is an area in the illumination region IRR where the colored light CL of the white light WL emitted from only one first small lens 131 of the plurality of first small lenses 131 is irradiated. That is, the region P1 is an area where the colored light CL (illumination light) does not overlap in the illumination region IRR. The region P2 is an area in the illumination region IRR where the colored light CL of each white light WL emitted from two first small lenses 131 of the plurality of first small lenses 131 is irradiated. That is, the region P2 is an area where two colored lights CL (illumination lights) overlap each other in the illumination region IRR. The region P3 is an area in the illumination region IRR where the colored light CL of each white light WL emitted from four first small lenses 131 of the plurality of first small lenses 131 is irradiated. That is, the region P3 is an area where four colored lights CL (illumination lights) overlap each other in the illumination region IRR. Note that the regions P2 and P3 are overlapping regions.

[0056] When the light intensity and illuminance of the colored light CL of the white light WL emitted from each of the first small lenses 131A and 131B can be considered to be uniform in the illumination region IRR, the light intensity and illuminance of the region P2 where the colored light CL of the white light WL emitted from the first small lens 131A and the colored light CL of the white light WL emitted from the first small lens 131B overlap twice are higher than the light intensity and illuminance of only the colored light CL of the white light WL emitted from each of the first small lenses 131A and 131B in the illumination region IRR. When the light intensity and illuminance of the colored light CL of the white light WL emitted from each of the multiple first small lenses 131 can be considered to be uniform in the illumination region IRR, the light intensity and illuminance of the region P3 where the colored light CL of the white light WL emitted from the first small lens 131 overlaps four times are even higher than the light intensity and illuminance of the region P2. In the illumination region IRR, an illuminance peak consisting of the regions P2 and P3, i.e., illuminance unevenness occurs.

[0057] The light intensity and illuminance of the regions P2 and P3 are higher than the light intensity and illuminance of the region P1 where the colored lights CL of the white light WL emitted from each of the multiple first small lenses 131 do not overlap each other, and are therefore suppressed to approximately the same level as the light intensity and illuminance of the region P1 by circuit correction of the projector 1. The circuit correction of the projector 1 is performed, for example, by adjusting and appropriately setting the gain of the portions corresponding to the regions P2 and P3 in the liquid crystal panels constituting each of the light modulation devices 4R, 4G, and 4B.

[0058] When circuit correction of the projector 1 is performed, the peak of the light intensity of the colored light CL in the illumination region IRR is detected. The detection of the peak of the light intensity of the colored light CL and the circuit correction of the projector 1 are generally performed when various settings are adjusted and various components are aligned, fine-tuned, and fixed as known during the manufacture of the projector 1. Specifically, an adjuster looks at a projection image for confirmation projected from the projector 1 and adjusts the gain of the liquid crystal panels constituting each of the light modulation devices 4R, 4G, and 4B so as to suppress unevenness in the illuminance of the projection image.

[0059] Although the gain of each liquid crystal panel of the light modulation devices 4R, 4G, and 4B is adjusted in advance when the projector 1 is manufactured, it is conceivable that the relative positions of the components housed in the internal space of the exterior body of the projector 1 may be shifted in situations such as when a user carries the projector 1, when the projector 1 is placed on an installation stand, or when something hits the projector 1. For this reason, if the projector 1 is equipped with an imaging device, the imaging device may capture an image or video enlarged and projected from the projector 1, detect the presence or absence of illuminance unevenness in the projected image and the location where it occurs, and adjust the gain of the liquid crystal panel constituting each of the light modulation devices 4R, 4G, and 4B so as to suppress the illuminance unevenness based on the detection result.

[0060] In the projector 1, the control device 110 receives luminance information of the colored light CL emitted from the second small lens 132A as the first illumination light, luminance information of the colored light CL emitted from the second small lens 132B as the second illumination light, and luminance information of an overlapping region where a part of the colored light CL emitted from the second small lens 132A and a part of the colored light CL emitted from the second small lens 132B overlap in the image formation region, i.e., the illumination region IRR. The control device 110 adjusts the gain of the liquid crystal panels constituting each of the light modulation devices 4R, 4G, and 4B based on the above-mentioned principle, and adjusts the luminance information of the image data corresponding to the overlapping region.

[0061] The control device 110 identifies areas P2 and P3, which are overlap areas, based on the imaging results of the projection image captured by the imaging device 120, adjusts the gain of the pixels in the overlap area identified on the liquid crystal panel, and adjusts the brightness information of the image data corresponding to the identified overlap area.

[0062] FIG. 5 is a schematic diagram of the incident surface 4a after the gain of the liquid crystal panel of the light modulation devices 4R, 4G, and 4B is adjusted, and is a diagram when the image forming area of ​​the incident surface 4a is viewed from the front along the optical axis of the red light RL included in the white light WL. FIG. 6 is a schematic diagram for explaining the principle of uniforming the light intensity and illuminance in the illumination area of ​​the light modulation devices 4R, 4G, and 4B in the illumination device 2 of this embodiment and suppressing illuminance unevenness. The schematic graph on the left side of FIG. 6 represents the light intensity distribution before correction. The schematic graph on the right side of FIG. 6 represents the light intensity distribution after correction. The horizontal axis of each distribution in FIG. 6 indicates the position in the illumination area IRR. The vertical axis of each distribution in FIG. 6 indicates the light intensity of the colored light CL, which means the total light intensity when the colored lights CL overlap each other.

[0063] The light intensity distribution of the colored light CL on the C1-C1 line shown in FIG. 4 and FIG. 5 is represented by LC1 in the graph on the left side of FIG. 6. The light intensity distribution of the colored light CL on the C2-C2 line shown in FIG. 4 and FIG. 5 is represented by LC2 in the graph on the left side of FIG. 6. In the light intensity distribution of the colored light CL represented by LC1, a light intensity I1 corresponding to the region P1 is obtained, and a peak of a light intensity I2 corresponding to the region P2 occurs. In the light intensity distribution of the colored light CL represented by LC2, a light intensity I2 corresponding to the region P2 is obtained, and a peak of a light intensity I3 corresponding to the region P3 occurs. Even if the light intensities I2 and I3 higher than the light intensity I1 are suppressed to the light intensity I1 in accordance with the lowest light intensity I1 in the illumination region IRR, the light intensity and illuminance of the colored light CL in the illumination region IRR are uniformed at least by the light intensity I1, as shown in the graph on the right side of FIG. 6. In the illumination region IRR, the regions P2 and P3 where the light intensities I2 and I3 are suppressed to the light intensity I1 are smaller than the region P1. Therefore, the loss of the color light CL in the liquid crystal panel of each of the optical modulation devices 4R, 4G, and 4B is small.

[0064] The illumination device 2 of the present embodiment described above includes a light source 21, a collimating element 22, a first lens array 34A, a second lens array 34B, and a superimposing lens (light collecting element) 33. The light source 21 emits blue light (light). The collimating element 22 collimates the blue light BL emitted from the light source 21. The white light WL including the blue light BL collimated by the collimating element 22 is incident on the first lens array 34A. The first lens array 34A includes a plurality of first small lenses 131. The white light WL emitted from the first lens array 34A is incident on the second lens array 34B. The second lens array 34B includes a plurality of second small lenses 132. The superimposing lens 33 collects the color light CL included in the white light WL emitted from the second lens array 34B toward the image forming area of ​​the incident surface 4a of each of the light modulation devices 4R, 4G, and 4B as the illumination area IRR. White light WL emitted from each of at least two first small lenses 131 is incident on one second small lens 132. A focal plane FPB of the multiple second small lenses 132 is located in front of a reference plane (virtual plane) MPB that includes multiple contact points CT between adjacent first small lenses 131 in the first lens array 34A, in the optical path along which the white light WL and the colored light CL travel.

[0065] In the illumination device 2 of the present embodiment, in an illumination region IRR corresponding to the image forming region of each of the light modulation devices 4R, 4G, and 4B, the colored lights CL split into partial light beams by the multiple first small lenses 131 of the first lens array 34A overlap with each other. The light intensities I2 and I3 of the regions P2 and P3 where the colored lights CL overlap are higher than at least the light intensity I1 of the region P1 where the colored lights CL do not overlap with each other. In the illumination device 2 of the present embodiment, since there is no region between the multiple colored lights CL in the illumination region IRR where the light intensity and illuminance are lower than the light intensity and illuminance of one colored light CL, a relatively dark portion is not generated in the projection image of the projector 1, and deterioration of image quality can be suppressed.

[0066] A comparative example of the configuration of the illumination device 2 of the present embodiment is a configuration in which the focal plane FPB of the second small lenses 132 is located at a later stage than the reference plane (virtual plane) MPB in the optical path along which the white light WL travels, similar to the configuration disclosed in Patent Document 1. In the configuration of the comparative example, in the illumination area IRR corresponding to the image forming area of ​​each of the light modulation devices 4R, 4G, and 4B, there are areas between the colored lights CL split into partial beams by the first small lenses 131 of the first lens array 34A where the colored lights CL are not illuminated. In the configuration of the comparative example, the areas in the illumination area IRR where the colored lights CL are not illuminated appear as relatively dark areas in the projection image of the projector, and even if the observer visually recognizes uneven illuminance, there is no way to brighten the dark areas, which leads to a deterioration in image quality.

[0067] A reference example of the configuration of the illumination device 2 of this embodiment is a configuration in which the focal plane FPB of the plurality of second small lenses 132 is at the same position as the reference plane (virtual plane) MPB in the optical path along which the white light WL travels, and the focal plane FPB and the reference plane MPB overlap each other. In the reference example configuration, in the illumination area IRR corresponding to each image forming area of ​​the light modulation devices 4R, 4G, and 4B, the colored lights CL split into partial light beams by the plurality of first small lenses 131 of the first lens array 34A are adjacent to each other without any gaps and are illuminated, so that basically there is no part where the colored light CL is not illuminated. Therefore, it is possible to suppress a decrease in image quality without causing relatively dark parts or uneven illuminance in the projection image of the projector. However, in the configuration of the reference example, if the focal plane FPB is shifted to a stage behind the reference plane MPB due to the positioning accuracy of the first lens array 34A and the second lens array 34B on the optical path along which the white light WL travels, the tolerance during assembly, and the impact of using the projector, the situation becomes similar to that of the configuration of the comparative example, causing the observer to visually recognize uneven illuminance, and the deterioration of image quality cannot be suppressed. Therefore, in the configuration of the reference example, there is a high possibility that relatively dark parts will be generated in the image projected by the projector, and the deterioration of image quality cannot be completely eliminated.

[0068] In the illumination device 2 of the present embodiment, a part of the colored light (first illumination light) CL emitted from one second small lens 132A of the multiple second small lenses 132 and a part of the colored light (second illumination light) CL emitted from another second small lens 132B of the multiple second small lenses 132 overlap in an illumination region IRR. The light intensities I2 and I3 of the colored light CL in regions P2 and P3 where the colored lights CL emitted from the second small lenses 132A and 132B overlap each other are greater than the light intensity I1 in the illumination region IRR of only the colored light CL emitted from the second small lens 132A and the light intensity I1 in the illumination region IRR of only the colored light CL emitted from the second small lens 132B.

[0069] In the illumination device 2 of the present embodiment, the light intensities I2, I3 of the colored lights CL in the regions P2, P3 where the colored lights CL overlap each other can be suppressed to the light intensity I1 of the region P1 where only one colored light CL is illuminated, as described with reference to Fig. 6, for example, to achieve uniformity in the light intensity and illuminance of the colored lights CL in the illumination region IRR. In order to suppress the light intensities I2, I3 of the colored lights CL in the regions P2, P3 to the light intensity I1, for example, the gains of the liquid crystal panels constituting each of the light modulation devices 4R, 4G, 4B at the locations corresponding to the regions P2, P3 can be adjusted and appropriately set using circuit correction of the projector 1.

[0070] FIG. 7 is a schematic diagram for explaining the principle of uniforming the light intensity and illuminance in the illumination area of ​​the light modulation devices 4R, 4G, and 4B and suppressing uneven illuminance in a configuration in which the focal plane FPB of the multiple second small lenses 132 is located behind the reference plane MPB as described above. The schematic graph on the left side of FIG. 7 shows the light intensity distribution before correction. The schematic graph on the right side of FIG. 7 shows the light intensity distribution after correction. The horizontal axis of each distribution in FIG. 7 indicates the position in the illumination area IRR. The vertical axis of each distribution in FIG. 7 indicates the light intensity of the colored light CL. As shown in FIG. 7, in the configuration of the comparative example, the light intensity I4 in the area where the colored light CL does not overlap with each other and is not illuminated by the colored light CL is lower than the light intensity I1 in the area P1 where only one colored light CL is illuminated. As shown in the schematic graph on the left side of FIG. 7, the light intensity I4 in the area where the colored light CL is not illuminated appears as a bottom or a base in the distribution of the light intensity I1. When the light intensity in the illumination region IRR is made uniform, for example, the light intensity I1 is suppressed to the light intensity I4 by using the circuit correction of the projector 1, as shown in the schematic graph on the right side of FIG. 7. In the illumination region IRR, the region P1 where the light intensity I1 is suppressed to the light intensity I4 is larger than the region where the colored light CL is not illuminated. Therefore, the loss of the colored light CL in each liquid crystal panel of the light modulation devices 4R, 4G, and 4B is large. On the other hand, in the illumination device 2 of this embodiment, in the illumination region IRR, the regions P2 and P3 where the light intensities I2 and I3 are suppressed to the light intensity I1 are smaller than the region P1. Therefore, the loss of the colored light CL in each liquid crystal panel of the light modulation devices 4R, 4G, and 4B can be suppressed to a small value.

[0071] In the illumination device 2 of this embodiment, the first small lenses 131 each have a convex first lens surface (first curved surface) 131r. The second small lenses 132 each have a convex second lens surface (second curved surface) 132r. The protruding direction of the first lens surface 131r may be the same as the protruding direction of the second lens surface 132r.

[0072] In the lighting device 2 of this embodiment, by setting the size of the second lens surface 132r to an integer multiple of the size of the first lens surface 131r in a plane perpendicular to the optical axis AX2, it is possible to perform area-divided illumination of the white light WL and the colored light CL into the illumination region IRR.

[0073] In the illumination device 2 of this embodiment, the first small lenses 131 each have a convex first lens surface (first curved surface) 131r. The second small lenses 132 each have a convex second lens surface (second curved surface) 132r. The protruding direction of the first lens surface 131r is opposite to the protruding direction of the second lens surface 132r.

[0074] In the illumination device 2 of the present embodiment, by setting the size of second lens surface 132r to an integer multiple of that of first lens surface 131r in a plane perpendicular to the optical axis AX2, it is possible to perform area division illumination of white light WL and colored light CL into illumination region IRR. In the illumination device 2 of the present embodiment, for example, the protruding direction of first lens surface 131r is a direction toward the incident side of white light WL on optical axis AX2 along the Y axis. The protruding direction of second lens surface 132r is a direction toward the exit side of white light WL on optical axis AX2 along the Y axis, which is the opposite direction to the protruding direction of first lens surface 131r.

[0075] The first lens array 34A and the second lens array 34B may be integrally formed on the optical axis AX2. A transparent member having translucency to the white light WL and a certain length may be sandwiched between the first lens array 34A and the second lens array 34B on the optical axis AX2. When the protruding direction of the first lens surface 131r faces the incident side of the white light WL and the protruding direction of the second lens surface 132r faces the exit side of the white light WL as in the illumination device 2 of this embodiment, the first lens array 34A and the second lens array 34B can be easily integrated.

[0076] The protruding direction of first lens surface 131r may be a direction toward the exit side of white light WL on optical axis AX2, and the protruding direction of second lens surface 132r may be a direction toward the entrance side of white light WL on optical axis AX2.

[0077] The projector 1 of this embodiment includes the above-mentioned illumination device 2, light modulation devices 4R, 4G, and 4B, and a projection optical system 6. The light modulation device 4R modulates red light RL contained in white light WL emitted from the illumination device 2 to generate red image light. The light modulation device 4G modulates green light GL contained in the white light WL to generate green image light. The light modulation device 4B modulates blue light BL contained in the white light WL to generate blue image light. The projection optical system 6 projects the image light (light) modulated by the light modulation devices 4R, 4G, and 4B.

[0078] In the projector 1 of this embodiment, the colored light CL included in the white light WL emitted from the illumination device 2 is illuminated in an area-divided manner on the image forming area of ​​the entrance surface 4a of each of the light modulation devices 4R, 4G, and 4B. The image forming area of ​​each of the light modulation devices 4R, 4G, and 4B is defined as an illumination area IRR. According to the projector 1 of this embodiment, since there is no area between the plurality of colored lights CL in the illumination area IRR where the light intensity and illuminance are lower than the light intensity and illuminance of one of the colored lights CL, and the light intensity and illuminance of at least one of the colored lights CL are secured within the illumination area IRR, it is possible to suppress degradation of image quality without generating relatively dark parts in the projected image.

[0079] In the projector 1 of this embodiment, the illumination region IRR is an image formation region that the light modulation devices 4R, 4G, and 4B have.

[0080] According to the projector 1 of this embodiment, the light intensity of areas P2 and P3 in the illumination area IRR where multiple colored lights CL overlap can be easily adjusted, for example, by changing the gain of the liquid crystal panels that constitute the light modulation devices 4R, 4G, and 4B.

[0081] The projector 1 of the present embodiment further includes a control device 110 that controls the driving of the light modulation devices 4R, 4G, and 4B based on luminance information of image data. The control device 110 adjusts luminance information of image data corresponding to an overlapping area where a portion of the color light (first illumination light) CL emitted from one second small lens 132A of the multiple second small lenses 132 and a portion of the color light (second illumination light) CL emitted from another second small lens 132B of the multiple second small lenses 132 overlap in an illumination area IRR, i.e., an image formation area.

[0082] According to the projector 1 of this embodiment, the gain of the driving region of the light modulation devices 4R, 4G, 4B corresponding to the overlap region where the color light CL emitted from one second small lens 132A and the color light CL emitted from one second small lens 132B overlap in the illumination region IRR can be adjusted by the control device 110. As a result, according to the projector 1 of this embodiment, it is possible to satisfactorily adjust the luminance information of the image data corresponding to the overlap region, suppress uneven illuminance in the projected image, and suppress deterioration of image quality.

[0083] The projector 1 of this embodiment further includes an imaging device 120 that captures a projection image including image light (light) projected by the projection optical system 6. The control device 110 specifies an overlapping area according to an imaging result captured by the imaging device 120, and adjusts luminance information of image data corresponding to the specified overlapping area.

[0084] In the projector 1 of this embodiment, after the manufacture and assembly of the projector 1 is completed, the areas P2 and P3, which are overlapping areas in the illumination area IRR, can be identified according to the imaging results obtained by the imaging device 120 that captures the projection image that is actually projected onto the screen SCR. The luminance information of the image data corresponding to the overlapping areas can be suitably adjusted using the control device 110. According to the projector 1 of this embodiment, it is possible to suppress uneven illuminance in the projected image and suppress deterioration of image quality at a speed close to real time during use.

[0085] Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to such specific embodiments, and various modifications and changes are possible within the scope of the gist of the present invention described in the claims.

[0086] For example, the shape, number, arrangement, and material of each component of the illumination device and projector are not limited to those described in the above-described embodiment and modified examples, and may be changed as appropriate.

[0087] The projector of the present invention does not need to have a plurality of light modulation devices, and may be a single-panel projector having only one light modulation device.

[0088] [Summary of this disclosure] The following is a summary of this disclosure. (Supplementary Note 1) An illumination device comprising: a light source that emits light; a collimating element that collimates the light emitted from the light source; a first lens array including a plurality of first small lenses onto which the light collimated by the collimating element is incident; a second lens array including a plurality of second small lenses onto which the light emitted from the first lens array is incident; and a focusing element that focuses the light emitted from the second lens array towards an illumination area, wherein each of the lights emitted from at least two of the first small lenses is incident on one of the second small lenses, and focal planes of the plurality of second small lenses are located in front of a virtual plane including a plurality of contact points between adjacent first small lenses in the first lens array, in an optical path along which the light travels.

[0089] The configuration of Appendix 1 prevents the creation of areas between multiple lights in the illumination area that have lower light intensity and illuminance than that of one color light, thereby preventing degradation of image quality without creating relatively dark areas in the projected image of the light emitted from the illumination device.

[0090] (Supplementary Note 2) The illumination device of Supplementary Note 1, wherein a portion of the first illumination light emitted from one of the plurality of second small lenses and a portion of the second illumination light emitted from another of the plurality of second small lenses overlap in the illumination area, and a light intensity in an area where the first illumination light and the second illumination light overlap is higher than a light intensity in the illumination area of ​​only the first illumination light and a light intensity in the illumination area of ​​only the second illumination light.

[0091] The configuration of Supplementary Note 2 makes it possible to uniformize the light intensity and illuminance of the light in the entire illumination area by suppressing the light intensity in the illumination area to that of an area illuminated by only one light.

[0092] (Supplementary Note 3) The lighting device of Supplementary Note 1 or Supplementary Note 2, wherein the first small lenses each have a convex first curved surface, and the second small lenses each have a convex second curved surface, and a protruding direction of the first curved surface is the same as a protruding direction of the second curved surface.

[0093] With the configuration of Supplementary Note 3, by setting the size of the second curved surface to an integer multiple of the size of the first curved surface in a plane perpendicular to the optical axis of the light, it is possible to perform area division illumination of the illumination area of ​​the light.

[0094] (Supplementary Note 4) The lighting device of Supplementary Note 1 or Supplementary Note 2, wherein the first small lenses each have a convex first curved surface, and the second small lenses each have a convex second curved surface, and a protruding direction of the first curved surface is opposite to a protruding direction of the second curved surface.

[0095] With the configuration of Supplementary Note 4, by setting the size of the second curved surface to an integer multiple of the size of the first curved surface in a plane perpendicular to the optical axis of the light, it is possible to perform area division illumination of the light illumination area. When the protruding direction of the first curved surface is opposite to the protruding direction of the second curved surface, the protruding direction of the first curved surface faces the light entrance side, and the protruding direction of the second curved surface faces the light exit side, it is easy to integrate the first lens array and the second lens array in the direction along the optical axis.

[0096] (Supplementary Note 5) A projector comprising: the above-mentioned illumination device; a light modulation device that modulates light from the illumination device; and a projection optical device that projects the light modulated by the light modulation device.

[0097] The configuration of Supplementary Note 5 ensures the light intensity and illuminance of at least one light in the illumination area without providing an area between multiple lights in which the light intensity and illuminance are lower than that of one light. Therefore, it is possible to suppress degradation of image quality without generating relatively dark areas in the projected image.

[0098] (Supplementary Note 6) The projector of Supplementary Note 5, wherein the illumination area is an image forming area of ​​the light modulation device.

[0099] With the configuration of Supplementary Note 6, the light intensity in the area where a plurality of lights overlap in the illumination area can be easily adjusted, for example, by changing the gain of the liquid crystal panel that constitutes the light modulation device.

[0100] (Supplementary Note 7) The projector of Supplementary Note 5 or Supplementary Note 6, further comprising a control device that controls driving of the light modulation device based on luminance information of image data, wherein the control device adjusts the luminance information of image data corresponding to an overlapping area where a portion of the first illumination light emitted from one of the plurality of second small lenses and a portion of the second illumination light emitted from another of the plurality of second small lenses overlap in the illumination area.

[0101] According to the configuration of Supplementary Note 7, the control device can adjust the gain of the driving region of the light modulation device corresponding to the overlap region where the light emitted from one second small lens and the light emitted from another second small lens overlap in the illumination region. According to the configuration of Supplementary Note 7, the luminance information of the image data corresponding to the overlap region can be favorably adjusted, and uneven illuminance in the projected image can be suppressed, thereby suppressing deterioration of image quality.

[0102] (Appendix 8) The projector of Appendix 7, further comprising an imaging device that captures a projection image including the light projected by the projection optical system, wherein the control device identifies the overlap area according to an imaging result captured by the imaging device, and adjusts the brightness information of image data corresponding to the identified overlap area.

[0103] In the configuration of Supplementary Note 8, after the manufacturing and assembly of the projector is completed, the overlapping area in the illumination area can be specified according to the imaging result obtained by the imaging device that captures the projection image that is actually projected on the screen or the like. The luminance information of the image data corresponding to the overlapping area can be suitably adjusted using the control device. With the configuration of Supplementary Note 8, it is possible to suppress uneven illuminance in the projection image and suppress deterioration of image quality at a speed close to real time during use. [Explanation of symbols]

[0104] 1...projector, 2...illumination device, 4B, 4G, 4R...light modulation device, 6...projection optical system, 21...light source, 22...collimating element, 34A...first lens array, 34B...second lens array, 33...superimposing lens (light-collecting element).

Claims

1. A light source that emits light; A collimating element that collimates the light emitted from the light source; a first lens array on which the light collimated by the collimating element is incident and which includes a plurality of first small lenses; a second lens array on which the light emitted from the first lens array is incident and which includes a plurality of second small lenses; a focusing element that focuses the light emitted from the second lens array toward an illumination area; Equipped with Each of the lights emitted from at least two of the first small lenses is incident on one of the second small lenses, The focal planes of the second small lenses are located in front of a virtual plane including a plurality of contact points between the first small lenses adjacent to each other in the first lens array, in an optical path along which the light travels. Lighting equipment.

2. a portion of the first illumination light emitted from one of the plurality of second small lenses and a portion of the second illumination light emitted from another of the plurality of second small lenses overlap in the illumination area; a light intensity in an area where the first illumination light and the second illumination light overlap each other is higher than a light intensity in the area illuminated by only the first illumination light and a light intensity in the area illuminated by only the second illumination light, 10. The lighting device of claim 1.

3. Each of the first small lenses has a first convex curved surface, each of the second small lenses has a convex second curved surface; The protruding direction of the first curved surface is the same as the protruding direction of the second curved surface. The lighting device according to claim 1 or 2.

4. Each of the first small lenses has a first convex curved surface, each of the second small lenses has a convex second curved surface; The protruding direction of the first curved surface is opposite to the protruding direction of the second curved surface. The lighting device according to claim 1 or 2.

5. The lighting device according to claim 1 or 2, a light modulation device that modulates light from the illumination device; a projection optical system that projects the light modulated by the light modulation device; Equipped with projector.

6. The illumination area is an image forming area of ​​the light modulation device. The projector according to claim 5 .

7. a control device that controls the driving of the light modulation device based on luminance information of image data; the control device adjusts the luminance information of the image data corresponding to an overlapping region in which a portion of the first illumination light emitted from one of the plurality of second small lenses and a portion of the second illumination light emitted from another of the plurality of second small lenses overlap in the illumination region. The projector according to claim 5 or 6.

8. an imaging device that captures a projection image including the light projected by the projection optical system; the control device specifies the overlapping area in accordance with an imaging result captured by the imaging device, and adjusts the luminance information of the image data corresponding to the specified overlapping area. The projector according to claim 7.

Images