Single-board projector

Abstract

A single-board projector is provided. Even if the light emitting area of the light source is increased in order to brighten the single-board projector, the light efficiency of the light source can be prevented from being reduced. The single-board projector includes: a first light source that emits first light; a second light source that emits second light different from the first light; a light synthesizing element that synthesizes the first light and the second light and emits synthesized light; a light modulation element that modulates the combined light into modulated light; and a projection lens that projects the modulated light.

Description

Technical Field

[0001] This utility model relates to a single-panel projector. Background Technology

[0002] Patent Document 1 describes a projector consisting of a single liquid crystal panel. This projector, referred to as a single-panel projector, includes: a light source; a converging optical system that converges light from the light source; a liquid crystal panel that modulates the light from the converging optical system to form an image; and a projection lens that projects the image generated by the liquid crystal panel onto a screen. The light source is a single LED light source.

[0003] Patent Document 1: Chinese Utility Model No. 212515320 Specification Utility Model Content

[0004] Here, there has been a persistent pursuit of projectors that project bright light. In this case, in the single-panel projector described in the aforementioned literature, a light source with a large emitting area is considered to achieve bright projected light. However, when the emitting area of ​​the light source is too large relative to the size of the effective display area of ​​the LCD panel, the following problem arises: the luminous efficiency of the light source decreases (the optical extension increases), so even if the emitting area of ​​the light source increases, the projected light will not become brighter.

[0005] To address the aforementioned issues, the single-panel projector of this invention is characterized by comprising: a first light source emitting a first light; a second light source emitting a second light different from the first light; a light combining element that combines the first light and the second light to emit combined light; a light modulation element that modulates the combined light into modulated light; and a projection lens that projects the modulated light. Attached Figure Description

[0006] Figure 1 This is a schematic diagram of the main parts of the projector in Embodiment 1.

[0007] Figure 2 This is a schematic diagram showing the pixels of an LCD panel.

[0008] Figure 3 This is a schematic diagram of the main parts of the projector in Embodiment 2.

[0009] Figure 4 This is a schematic diagram of the main parts of the projector in Embodiment 3.

[0010] Figure 5 This is a schematic diagram of the main parts of the projector in Embodiment 4.

[0011] Figure 6This is a schematic diagram showing the light-emitting element of the first light source in Embodiment 4.

[0012] Figure 7 This is a schematic diagram of the main parts of the projector in Embodiment 5.

[0013] Figure 8 This is a schematic diagram showing the light-emitting element of the first light source in Embodiment 5.

[0014] Figure 9 This is a schematic diagram of the main parts of the projector in Embodiment 6.

[0015] Label Explanation

[0016] 1. 1A, 1B, 1C, 1D, 1E: Projector; 2. 2A, 2B, 2C, 2D, 2E: Light source device; 3: Image forming unit; 4: Projection lens; 5: Reflector; 6: Control unit; 10: Light source; 11: First light source; 12: Second light source; 13: Third light source; 15: Pick-up lens; 16: Light combining element; 17: Dichroic mirror; 19: Dichroic prism; 21: First Fresnel lens; 22: First polarizing plate; 23: Light modulation element; 24: Second polarizing plate; 25: Second Fresnel lens; 111: First light-emitting element; 112: Second light-emitting element; 115: Fluorescent element; 116: First light-emitting element; 121: Second light-emitting element. Light element; 122: 3rd light-emitting element; 126: 3rd light-emitting element; 136: 3rd light-emitting element; 170: Base; 171: 1st surface; 172: 2nd surface; 173: Dielectric multilayer film; 191: 1st surface; 192: 2nd surface; 193: 3rd surface; 194: 4th surface; 195: 1st color separation film; 196: 2nd color separation film; 230: Liquid crystal panel; 231B: 1st sub-pixel; 231G: 2nd sub-pixel; 231R: 3rd sub-pixel; E: Area; LA: Modulated light; LB: Blue light; LC: Mixed light; LG: Green light; LR: Red light; LW: White light; LY: Yellow light; N: 1st axis; S: Screen. Detailed Implementation

[0017] The following describes the projector according to an embodiment of the present invention with reference to the accompanying drawings.

[0018] Implementation Method 1

[0019] Figure 1 This is a schematic diagram of the main parts of the projector in Embodiment 1. Figure 2 This is a schematic diagram showing the pixels of an LCD panel. (Example) Figure 1As shown, the projector 1 includes: a light source device 2; an image forming unit 3 that generates a projected image that is projected onto a screen S; a projection lens 4 that magnifies the projected image and projects it onto the screen S; a reflector 5 disposed between the image forming unit 3 and the projection lens 4; and a control unit 6 that controls the operation of the image forming unit 3.

[0020] The light source device 2 includes a light source 10, a pickup lens 15, and a light combining element 16. The light source 10 is, for example, composed of an ultra-high pressure mercury lamp or a solid-state light source. In this embodiment, the light source 10 is an LED. The light source 10 includes: a first light source 11 that emits a first light; and a second light source 12 that emits a second light different from the first light. Here, as... Figure 1 As shown, when the three mutually orthogonal axes are designated as the X-axis, Y-axis, and Z-axis, the X-axis is the first axis N along the arrangement direction of the image forming unit 3 and the reflector 5. On the X-axis, the direction where the first light source 11 is located is designated as the X1 direction, and the direction where the reflector 5 is located is designated as the X2 direction. The Y-axis is an axis parallel to the direction where the second light source 12 and the light combining element 16 are arranged, and the direction where the reflector 5 and the projection lens 4 are arranged. On the Y-axis, the direction where the second light source 12 and the projection lens 4 are located is designated as the Y1 direction, and the opposite direction is designated as the Y2 direction.

[0021] like Figure 1 As shown, the first light source 11 is located in the X1 direction of the light combining element 16. In this embodiment, the first light emitted by the first light source 11 is yellow light LY. The wavelength of the yellow light LY is, for example, 500nm to 680nm, and includes green and red light. The first light source 11 includes a first light-emitting element 111 and a fluorescent element 115 covering the emitting surface of the first light-emitting element 111. The first light-emitting element 111 is a blue LED element that emits blue light. In this embodiment, the fluorescent element 115 is a yellow phosphor. The fluorescent element 115 converts the blue light emitted from the first light-emitting element 111 into yellow light LY as the first light.

[0022] The second light source 12 is located in the Y1 direction of the light combining element 16. In this configuration, the second light emitted by the second light source 12 is blue light LB. The wavelength of the blue light LB is, for example, 420nm to 500nm. The second light source 12 includes a second light-emitting element 121 that emits blue light LB. The second light-emitting element 121 is a blue LED element. In this configuration, the light-emitting area of ​​the first light source 11 is the same as the light-emitting area of ​​the second light source 12.

[0023] The pickup lens 15 makes the light from the light source 10 approximately parallel and emits it toward the light combining element 16. The light combining element 16 combines yellow light LY and blue light LB to emit white light LW in the X2 direction as the combined light. In this embodiment, the light combining element 16 is a dichroic mirror 17. The dichroic mirror 17 has a plate-shaped base 170, which includes a first surface 171 and a second surface 172 facing the side opposite to the first surface 171. In this embodiment, a dielectric multilayer film 173 is provided on the first surface 171. The dielectric multilayer film 173 transmits yellow light LY and reflects blue light LB. Thus, the dichroic mirror 17 emits white light LW obtained by combining yellow light LY and blue light LB.

[0024] The image forming unit 3 includes a first Fresnel lens 21, a first polarizer 22, an optical modulation element 23, a second polarizer 24, and a second Fresnel lens 25. The first light source 11, the first Fresnel lens 21, the first polarizer 22, the optical modulation element 23, the second polarizer 24, the second Fresnel lens 25, and the reflector 5 are arranged along the first axis N.

[0025] The first Fresnel lens 21 parallelizes the light rays emitted from the light source 10. The first polarizing plate 22 is disposed on the incident side of the light modulation element 23, allowing either the P-polarization component or the S-polarization component of the polarization composition of the white light LW emitted from the first Fresnel lens 21 to be transmitted or reflected. In this configuration, the first polarizing plate 22 is a transmission-type polarizing plate, allowing the P-polarization component of the polarization composition of the white light LW emitted from the first Fresnel lens 21 to be transmitted.

[0026] The light modulation element 23 modulates the white light LW, whose P-polarization component has passed through the first polarizing plate 22, into modulated light LA, forming a projected image. The light modulation element 23 is a liquid crystal panel 230. The effective display area of ​​the liquid crystal panel 230 has dimensions of 6.48 mm × 11.52 mm (0.52 inches) to 99.6 mm × 176.8 mm (8.0 inches). In this embodiment, the liquid crystal panel 230 consists of a single panel, forming a full-color projected image. That is, the projector 1 in this embodiment is a full-color single-panel projector. Figure 2As shown, the liquid crystal panel 230 includes a first sub-pixel 231B that receives blue light, a second sub-pixel 231G that receives green light, and a third sub-pixel 231R that receives red light. A microlens array (not shown) with multiple microlenses is disposed on the incident side of the liquid crystal panel 230. The multiple microlenses allow the color light corresponding to each sub-pixel 231B-231R to be incident on each sub-pixel 231B-231R. When the color light corresponding to each sub-pixel 231B-231R is incident on each sub-pixel 231B-231R, each sub-pixel 231B-231R modulates the corresponding color light. Thus, the liquid crystal panel 230 forms a full-color projected image as the modulation light LA.

[0027] The second polarizer 24 is disposed on the emission side of the optical modulation element 23, and allows transmission of either the P-polarization component or the S-polarization component of the polarization composition of the modulated light LA ​​emitted from the optical modulation element 23. In this configuration, the second polarizer 24 allows transmission of the S-polarization component of the polarization composition of the modulated light LA ​​emitted from the optical modulation element 23. The second Fresnel lens 25 converges the modulated light LA ​​emitted from the second polarizer 24 onto the projection lens 4.

[0028] The reflector 5 is arranged along the first axis N. The reflector 5 reflects the modulated light LA ​​emitted from the second Fresnel lens 25 toward the projection lens 4. In this embodiment, the reflector 5 bends the modulated light LA ​​by 90°. The projection lens 4 magnifies the modulated light LA ​​emitted from the second Fresnel lens 25 and projects it onto the screen S. The projection lens 4 has multiple lenses. The control unit 6 operates the liquid crystal panel 230 based on external image signals such as video signals.

[0029] Effects

[0030] The projector 1 of this method is a single-panel type. Projector 1 includes: a first light source 11 that emits yellow light LY; a second light source 12 that emits blue light LB, which is different from the yellow light LY; a light combining element 16 that combines the yellow light LY and the blue light LB to emit white light LW; a light modulation element 23 that modulates the white light LW into modulated light LA; and a projection lens 4 that projects the modulated light LA. According to this method, projector 1 has two light sources. Therefore, the emitting area of ​​the light source is divided by the first light source 11 and the second light source 12, and thus the emitting areas of the first light source 11 and the second light source 12 are smaller compared to the case with a single light source. As a result, even when the emitting area of ​​the light source is increased to make projector 1 brighter, the emitting areas of the first light source 11 and the second light source 12 can be kept small, thus suppressing the decrease in light efficiency of the light source (increased optical extension), and making the projected light of projector 1 brighter.

[0031] The light-combining element 16 has a plate-shaped base 170, which includes a first surface 171 and a second surface 172 facing the side opposite to the first surface 171. A dielectric multilayer film 173 is provided on the first surface 171. The dielectric multilayer film 173 transmits yellow light LY, which is the first light, and reflects blue light LB, which is the second light. That is, the light-combining element 16 is a dichroic mirror 17. The optical axis offset between the yellow light LY transmitted by the dichroic mirror 17 and the blue light LB reflected by the dichroic mirror 17 is suppressed. In addition, compared with the case where the light-combining element 16 is a dichroic prism, the space for arranging the dichroic mirror 17 is smaller.

[0032] The first light source 11 includes a first light-emitting element 111 and a fluorescent element 115 that converts the light emitted from the first light-emitting element 111 into a first light. The first light is yellow light LY. The second light is blue light LB. As a result, the synthesized light synthesized by the light-synthesizing element 16 can be made into white light LW containing red light, green light and blue light, and thus the color gamut of the modulated light LA ​​projected by the projector 1 is widened.

[0033] The luminous area of ​​the first light source 11 is the same as that of the second light source 12. This suppresses color unevenness in the white light LW used as the composite light.

[0034] The projector 1 of this method has a reflector 5 that reflects the modulated light LA ​​emitted from the light modulation element 23 toward the projection lens 4. The light combining element 16, the light modulation element 23, and the reflector 5 are arranged along the first axis N. The second light source 12 and the projection lens 4 are arranged in the same direction intersecting the first axis N, i.e., the Y1 direction. As a result, the size of the projector 1 along the first axis N is miniaturized.

[0035] The projector 1 also includes: a first polarizing plate 22 disposed on the incident side of the light modulation element 23 to transmit the synthesized light; and a second polarizing plate 24 disposed on the emitting side of the light modulation element 23 to transmit the modulated light LA ​​from the light modulation element 23. Figure 2 As shown, the liquid crystal panel 230, which serves as the light modulation element 23, includes a first sub-pixel 231B that receives blue light, a second sub-pixel 231G that receives green light, and a third sub-pixel 231R that receives red light. Therefore, compared to a projector with three liquid crystal panels, the projector 1 of this type has only one liquid crystal panel 230 for forming a full-color projected image, thus achieving miniaturization.

[0036] Implementation Method 2

[0037] Figure 3This is a schematic diagram of the main parts of the projector 1A in Embodiment 2. The light source device 2A of the projector 1A in Embodiment 2 is different from that of the projector 1 in Embodiment 1. Therefore, in Embodiment 2, the same reference numerals are sometimes used for structures that are the same as those in Embodiment 1, and descriptions are omitted.

[0038] like Figure 3 As shown, the light source device 2A includes a light source 10, a pickup lens 15, and a light combining element 16. In this embodiment, the light source 10 is an LED. The light source 10 includes: a first light source 11 that emits a first light; and a second light source 12 that emits a second light different from the first light.

[0039] The first light source 11 is located in the X1 direction of the photosynthesizing element 16. In this embodiment, the first light emitted by the first light source 11 is white light LW. The wavelength range of the white light LW is, for example, 420 nm to 680 nm. The first light source 11 includes a first light-emitting element 111 and a fluorescent element 115 covering the emitting surface of the first light-emitting element 111. The first light-emitting element 111 is a blue LED element that emits blue light. In this embodiment, the fluorescent element 115 includes a phosphor that emits red light and a phosphor that emits green light. The fluorescent element 115 converts the blue light emitted from the first light-emitting element 111 into white light LW as the first light.

[0040] The second light source 12 is located in the Y1 direction of the light combining element 16. In this configuration, the second light emitted by the second light source 12 is red light LR. The wavelength of the red light LR is, for example, 600nm to 680nm. The second light source 12 includes a second light-emitting element 121 that emits red light LR. The second light-emitting element 121 is a red LED element. In this configuration, the light-emitting area of ​​the first light source 11 is the same as the light-emitting area of ​​the second light source 12.

[0041] The pickup lens 15 makes the light from the light source 10 approximately parallel and emits it toward the light combining element 16. The light combining element 16 combines white light LW and red light LR, and emits white light LW as the combined light in the X2 direction. In this embodiment, the light combining element 16 is a dichroic mirror 17. The dichroic mirror 17 has a plate-shaped base 170, which includes a first surface 171 and a second surface 172 facing the side opposite to the first surface 171. In this embodiment, a dielectric multilayer film 173 is provided on the first surface 171. The dielectric multilayer film 173 transmits blue light LB and green light LG and reflects red light LR. Thus, the dichroic mirror 17 emits white light LW obtained by combining white light LW and red light LR. In addition, the dielectric multilayer film 173 reflects the red light LR in the white light LW of the first light source 11 in the Y2 direction.

[0042] Effects

[0043] According to this method, even if the overall luminous area of ​​the light source 10 is increased, the luminous areas of the first light source 11 and the second light source 12 can be suppressed to be small. Therefore, the projector 1A can achieve the same effect as in embodiment 1.

[0044] The first light source 11 includes a first light-emitting element 111 and a fluorescent element 115 that converts the light emitted from the first light-emitting element 111 into a first light. The first light is white light LW. The second light is red light LR. Here, regarding the white light LW converted by the fluorescent element 115, the light intensity of the red light LR contained in the white light LW tends to decrease. According to this method, the second light is red light LR, therefore, the light intensity of the red light LR of the white light LW synthesized by the light-combining element 16 increases. As a result, the hue of the white light LW synthesized by the light-combining element 16 is corrected. In addition, since the hue of the white light LW synthesized by the light-combining element 16 is corrected, the white balance of the projected image projected by the projector 1A is improved.

[0045] Implementation Method 3

[0046] Figure 4 This is a schematic diagram of the main parts of the projector 1B in Embodiment 3. The light source device 2B of the projector 1B in Embodiment 3 is different from that of the projector 1 in Embodiment 1. Therefore, in Embodiment 3, the same reference numerals are sometimes used for structures that are the same as those in Embodiment 1, and descriptions are omitted.

[0047] like Figure 4 As shown, the light source device 2B includes a light source 10, a pickup lens 15, and a light combining element 16. In this embodiment, the light source 10 is an LED. The light source 10 includes: a first light source 11 that emits a first light; and a second light source 12 that emits a second light different from the first light.

[0048] The first light source 11 is located in the X1 direction of the photosynthesizing element 16. In this embodiment, the first light emitted by the first light source 11 is green light LG. The wavelength of the green light LG is, for example, 500 nm to 600 nm. The first light source 11 includes a first light-emitting element 111 and a fluorescent element 115 covering the emitting surface of the first light-emitting element 111. The first light-emitting element 111 is a blue LED element that emits blue light. In this embodiment, the fluorescent element 115 is a green phosphor. The fluorescent element 115 converts the blue light LB emitted from the first light-emitting element 111 into green light LG as the first light.

[0049] The second light source 12 is located in the Y1 direction of the light combining element 16. In this configuration, the second light emitted by the second light source 12 is a mixed light LC comprising blue light LB and red light LR. The wavelength range of the blue light LB is, for example, 420nm to 500nm. The wavelength range of the red light LR is, for example, 600nm to 680nm. The second light source 12 includes a second light-emitting element 121 that emits blue light LB and a third light-emitting element 122 that emits red light LR. The second light-emitting element 121 is a blue LED element. The third light-emitting element 122 is a red LED element. In this configuration, the light-emitting area of ​​the first light source 11 is the same as the light-emitting area of ​​the second light source 12.

[0050] The pickup lens 15 makes the light from the light source 10 approximately parallel and emits it toward the light combining element 16. The light combining element 16 combines the green light LG and the mixed light LC, and emits white light LW in the X2 direction as the combined light. In this embodiment, the light combining element 16 is a dichroic mirror 17. The dichroic mirror 17 has a plate-shaped base 170, which includes a first surface 171 and a second surface 172 facing the side opposite to the first surface 171. In this embodiment, a dielectric multilayer film 173 is provided on the first surface 171. The dielectric multilayer film 173 transmits the green light LG and reflects the mixed light LC, namely the blue light LB and the red light LR. Thus, the dichroic mirror 17 emits white light LW obtained by combining the green light LG and the mixed light LC.

[0051] Effects

[0052] According to this method, even if the overall luminous area of ​​the light source 10 is increased, the luminous areas of the first light source 11 and the second light source 12 can be suppressed to be small. Therefore, the projector 1B can achieve the same effect as in embodiment 1.

[0053] The first light source 11 includes a first light-emitting element 111 and a fluorescent element 115 that converts the light emitted from the first light-emitting element 111 into a first light. The first light is green light LG. The second light is a mixed light LC containing blue light LB and red light LR. Thus, the light intensity of the green light LG contained in the white light LW synthesized by the light-combining element 16 increases. Consequently, the light intensity of the green light LG contained in the modulated light LA ​​projected from the projector 1B increases, and therefore the projected image becomes a vivid image.

[0054] Implementation Method 4

[0055] Figure 5 This is a schematic diagram of the main parts of the projector 1C according to embodiment 4. Figure 6This is a schematic diagram showing the light-emitting element of the first light source in Embodiment 4. The light source device 2C of the projector 1C in Embodiment 4 is different from that of the projector 1 in Embodiment 1. Therefore, in Embodiment 4, the same reference numerals are sometimes used for structures that are the same as those in Embodiment 1, and descriptions are omitted.

[0056] like Figure 5 As shown, the light source device 2C includes a light source 10, a pickup lens 15, and a light combining element 16. In this embodiment, the light source 10 is an LED. The light source 10 includes: a first light source 11 that emits a first light; and a second light source 12 that emits a second light different from the first light.

[0057] The first light source 11 is located in the X1 direction of the light combining element 16. In this configuration, the first light emitted from the first light source 11 is a mixed light LC comprising blue light LB and green light LG. The wavelength of the blue light LB is, for example, 420 nm to 500 nm. The wavelength of the green light LG is, for example, 500 nm to 600 nm.

[0058] The first light source 11 includes a first light-emitting element 111 and a second light-emitting element 112. The first light-emitting element 111 is a blue LED element that emits blue light LB. The second light-emitting element 112 is a green LED element that emits green light LG. In this embodiment, the total number of second light-emitting elements 112 is greater than the total number of first light-emitting elements 111. Figure 6 As shown, in the first light source 11, the second light-emitting element 112 is disposed in the outermost periphery of the region E in which the first light-emitting element 111 and the second light-emitting element 112 are disposed. In addition, the first light-emitting element 111 is surrounded by the second light-emitting element 112.

[0059] like Figure 5 As shown, the second light source 12 is located in the Y1 direction of the light combining element 16. In this configuration, the second light emitted by the second light source 12 is red light LR. The wavelength of the red light LR is, for example, 600nm to 680nm. The second light source 12 includes a third light-emitting element 126 that emits red light LR. The third light-emitting element 126 is a red LED element. In this configuration, the light-emitting area of ​​the first light source 11 is the same as the light-emitting area of ​​the second light source 12.

[0060] The pickup lens 15 makes the light from the light source 10 approximately parallel and emits it toward the light combining element 16. The light combining element 16 combines the mixed light LC and the red light LR, and emits white light LW in the X2 direction as the combined light. In this embodiment, the light combining element 16 is a dichroic mirror 17. The dichroic mirror 17 has a plate-shaped base 170, which includes a first surface 171 and a second surface 172 facing the side opposite to the first surface 171. In this embodiment, a dielectric multilayer film 173 is provided on the first surface 171. The dielectric multilayer film 173 transmits blue light LB and green light LG, and reflects red light LR. Thus, the dichroic mirror 17 emits white light LW obtained by combining the mixed light LC and the red light LR.

[0061] Effects

[0062] According to this method, even if the overall luminous area of ​​the light source 10 is increased, the luminous areas of the first light source 11 and the second light source 12 can be suppressed to be small. Therefore, the projector 1C can achieve the same effect as in embodiment 1.

[0063] The first light source 11 includes a first light-emitting element 111 that emits blue light LB and a second light-emitting element 112 that emits green light LG. The second light source 12 includes a third light-emitting element 126 that emits red light LR. As a result, compared with the case where the light emitted from the first light-emitting element is converted into a mixed light containing blue and green light by using a fluorescent element, the spectral distribution width of the mixed light LC emitted from the first light source 11 in this manner is narrower. Therefore, the color gamut of the white light LW, which is the composite light obtained by combining the mixed light LC and the red light LR, is widened.

[0064] Here, the light intensity of the LED element emitting red light LR is lower than that of the LED element emitting blue light LB and the LED element emitting green light LG. Therefore, according to this method, the second light source 12 only has a third light-emitting element 126 that serves as the LED element emitting red light LR, thus the light intensity of the red light LR contained in the white light LW, which is the synthesized light, becomes higher. As a result, the hue of the white light LW synthesized by the light-combining element 16 is corrected, and therefore, the white balance of the projected image projected by the projector 1C is improved.

[0065] The total number of the second light-emitting elements 112 is greater than the total number of the first light-emitting elements 111. The second light-emitting elements 112 are positioned at the outermost periphery of the region E in which the first light source 11 is configured with both the first and second light-emitting elements 111. This makes it easy to uniformly distribute the first and second light-emitting elements 111 in region E even when the total number of the second light-emitting elements 112 is greater than the total number of the first light-emitting elements 111. Furthermore, it is possible to make the light intensity of the green light LG contained in the mixed light LC higher than the light intensity of the blue light LB. As a result, the light intensity of the green light LG contained in the modulated light LA ​​projected from the projector increases, thus producing a vivid projected image.

[0066] Implementation 5

[0067] Figure 7 This is a schematic diagram of the main parts of the projector 1D in embodiment 5. Figure 8 This is a schematic diagram showing the light-emitting element of the first light source in Embodiment 5. The light source device 2D of the projector 1D in Embodiment 5 is different from that of the projector 1 in Embodiment 1. Therefore, in Embodiment 5, the same reference numerals are sometimes used for structures that are the same as those in Embodiment 1, and descriptions are omitted.

[0068] like Figure 7 As shown, the light source device 2D includes a light source 10, a pickup lens 15, and a light combining element 16. In this embodiment, the light source 10 is an LED. The light source 10 includes: a first light source 11 that emits a first light; and a second light source 12 that emits a second light different from the first light.

[0069] The first light source 11 is located in the X1 direction of the light combining element 16. In this configuration, the first light emitted from the first light source 11 is a mixed light LC comprising blue light LB and red light LR. The wavelength of the blue light LB is, for example, 420 nm to 500 nm. The wavelength of the red light LR is, for example, 600 nm to 680 nm.

[0070] The first light source 11 includes a first light-emitting element 111 and a second light-emitting element 112. The first light-emitting element 111 is a blue LED element that emits blue light LB. The second light-emitting element 112 is a red LED element that emits red light LR. In this configuration, the total number of second light-emitting elements 112 is greater than the total number of first light-emitting elements 111. Figure 8 As shown, the second light-emitting element 112 is disposed on the outermost periphery of the region E in which the first light-emitting element 111 and the second light-emitting element 112 are disposed. In addition, the first light-emitting element 111 is surrounded by the second light-emitting element 112.

[0071] like Figure 7As shown, the second light source 12 is located in the Y1 direction of the light combining element 16. In this embodiment, the second light emitted by the second light source 12 is green light LG. The wavelength of the green light LG is, for example, 500nm to 600nm. The second light source 12 includes a third light-emitting element 126 as a green LED element that emits green light LG. In this embodiment, the light-emitting area of ​​the first light source 11 is the same as the light-emitting area of ​​the second light source 12.

[0072] The pickup lens 15 makes the light from the light source 10 approximately parallel and emits it toward the light combining element 16. The light combining element 16 combines the mixed light LC and the green light LG, and emits white light LW in the X2 direction as the combined light. In this embodiment, the light combining element 16 is a dichroic mirror 17. The dichroic mirror 17 has a plate-shaped base 170, which includes a first surface 171 and a second surface 172 facing the side opposite to the first surface 171. In this embodiment, a dielectric multilayer film 173 is provided on the first surface 171. The dielectric multilayer film 173 transmits blue light LB and red light LR, and reflects green light LG. Thus, the dichroic mirror 17 emits white light LW obtained by combining the mixed light LC and the green light LG.

[0073] Effects

[0074] According to this method, even if the overall luminous area of ​​the light source 10 is increased, the luminous areas of the first light source 11 and the second light source 12 can be suppressed to be small. Therefore, the projector 1D can achieve the same effect as in embodiment 1.

[0075] The first light source 11 includes a first light-emitting element 111 that emits blue light LB and a second light-emitting element 112 that emits red light LR. The second light source 12 includes a third light-emitting element 126 that emits green light LG. This increases the light intensity of the green light LG contained in the white light LW synthesized by the light-combining element 16. Consequently, the light intensity of the green light LG contained in the modulated light LA ​​projected from the projector increases, resulting in a vivid projected image.

[0076] The total number of second light-emitting elements 112 is greater than the total number of first light-emitting elements 111. The second light-emitting elements 112 are disposed on the outermost periphery of the region E in which the first light source 11 is configured with both the first and second light-emitting elements 111. This ensures that even when the total number of second light-emitting elements 112 is greater than the total number of first light-emitting elements 111, the first and second light-emitting elements 111 can be easily and evenly distributed in region E.

[0077] Here, the light intensity of the LED element emitting red light LR is lower than the light intensity of the LED element emitting blue light LB. Therefore, according to this method, in the first light source 11, the total number of second light-emitting elements 112 emitting red light LR is greater than the total number of first light-emitting elements 111 emitting blue light LB, and thus, the light intensity of blue light LB and red light LR in the mixed light LC are equal.

[0078] Implementation Method 6

[0079] Figure 9 This is a schematic diagram of the main parts of the projector 1E in Embodiment 6. The light source device 2E of the projector 1E in Embodiment 6 is different from that of the projector 1 in Embodiment 1. Therefore, in Embodiment 6, the same reference numerals are sometimes used for structures that are the same as those in Embodiment 1, and descriptions are omitted.

[0080] The light source device 2E includes a light source 10, a pickup lens 15, and a light combining element 16. In this embodiment, the light source 10 is an LED. The light source 10 includes: a first light source 11 that emits a first light; a second light source 12 that emits a second light different from the first light; and a third light source 13 that emits a third light different from the first and second lights.

[0081] like Figure 9 As shown, the first light source 11 is located in the X1 direction of the light combining element 16. In this embodiment, the first light emitted by the first light source 11 is green light LG. The wavelength of the green light LG is, for example, 500nm to 600nm. The first light source 11 includes a first light-emitting element 116 that emits green light LG. The first light-emitting element 116 is a green LED element.

[0082] The second light source 12 is located in the Y1 direction of the light combining element 16. In this embodiment, the second light emitted by the second light source 12 is blue light LB. The wavelength of the blue light LB is, for example, 420nm to 500nm. The second light source 12 includes a second light-emitting element 121 that emits blue light LB. The second light-emitting element 121 is a blue LED element.

[0083] The third light source 13 is located in the Y2 direction of the light combining element 16. In this embodiment, the third light emitted by the third light source 13 is red light LR. The wavelength of the red light LR is, for example, 600nm to 680nm. The third light source 13 includes a third light-emitting element 136 that emits red light LR. The third light-emitting element 136 is a red LED element.

[0084] In this method, the size of the emitting surface of the first light source 11 is 0.25mm×0.25mm to 10mm×10mm. The size of the emitting surface of the second light source 12 is 0.25mm×0.25mm to 10mm×10mm. The size of the emitting surface of the third light source 13 is 0.5mm×0.5mm to 20mm×20mm.

[0085] The picking lens 15 makes the light from the light source 10 approximately parallel and emits it toward the light combining element 16. The light combining element 16 combines blue light LB, green light LG, and red light LR, and emits white light LW in the X2 direction as the combined light. In this method, the light combining element 16 is a dichroic prism 19. The dichroic prism 19 is a cuboid shape composed of four triangular prisms. The dichroic prism 19 has: a first surface 191, which is opposite to the first light source 11 and allows green light LG to be incident; a second surface 192, which is opposite to the second light source 12 and allows blue light LB to be incident; a third surface 193, which is opposite to the third light source 13 and allows red light LR to be incident; and a fourth surface 194, which emits white light LW obtained by combining blue light LB, green light LG, and red light LR.

[0086] The dichroic prism 19 includes a first dichroic film 195 and a second dichroic film 196. Both the first dichroic film 195 and the second dichroic film 196 are dielectric multilayer films. The first dichroic film 195 transmits green light LG and red light LR, and reflects blue light LB. The second dichroic film 196 transmits blue light LB and green light LG, and reflects red light LR. Thus, the dichroic prism 19 emits white light LW from its fourth surface 194, combining the blue light LB, green light LG, and red light LR.

[0087] Effects

[0088] According to this method, even if the overall luminous area of ​​the light source 10 is increased, the luminous areas of the first light source 11, the second light source 12, and the third light source 13 can be suppressed to be small. Therefore, the projector 1E can achieve the same effect as in embodiment 1.

[0089] The projector 1E of this method also has a third light source 13, which emits a third light different from the first and second lights. The first light source 11 emits green light LG as the first light. The second light source 12 emits blue light LB as the second light. The third light source 13 emits red light LR as the third light. The light combining element 16 includes: a first surface 191, which faces the first light source 11 and receives green light LG; a second surface 192, which faces the second light source 12 and receives blue light LB; a third surface 193, which faces the third light source 13 and receives red light LR; and a fourth surface 194, which emits white light LW obtained by combining blue light LB, green light LG, and red light LR. Thus, the light emission of the first light source 11, the second light source 12, and the third light source 13 can be adjusted separately, and therefore, the white balance of the projected image projected by the projector 1E can be easily adjusted.

[0090] In the projector 1E of this method, the effective display area size of the light modulation element 23 is 6.48mm × 11.52mm to 99.6mm × 176.8mm. The size of the emitting surface of the first light source 11 is 0.25mm × 0.25mm to 10mm × 10mm. The size of the emitting surface of the second light source 12 is 0.25mm × 0.25mm to 10mm × 10mm. The size of the emitting surface of the third light source 13 is 0.5mm × 0.5mm to 20mm × 20mm. Therefore, it is possible to suppress the enlargement of the light modulation element 23 and to suppress the reduction in the light efficiency of the first light source 11, the second light source 12, and the third light source 13.

[0091] Other implementation methods

[0092] In embodiments 1 to 5, the luminous area of ​​the first light source 11 is the same as that of the second light source 12. However, in other embodiments, the luminous area of ​​the first light source 11 may be larger than that of the second light source 12. In this case, the luminous efficiency of the first light based on the first light source 11 may be lower than that of the second light based on the second light source 12. This prevents the luminous area of ​​the second light source 12 from becoming larger, and because the overall luminous area of ​​the light source 10 becomes larger, the projected light from the projector becomes brighter. Furthermore, the luminous efficiency of the second light source with its smaller luminous area is higher, thus improving the white balance of the projected image projected by the projector. Here, the luminous efficiency is calculated by dividing the amount of light generated by the light source (in W) by the power input to the light source (in W) for emitting light.

[0093] In the above embodiment, the light modulation element 23 is a transmissive liquid crystal panel, but in other embodiments, the light modulation element 23 may also be a reflective liquid crystal panel, a DMD (digital micromirror device), or the like. The light modulation element 23 may also not form a full-color projected image.

[0094] In the above method, the first polarizing plate 22 is a transmission type polarizing plate, but it can also be a reflection type polarizing plate.

[0095] In the above embodiment, the projector has a reflector 5, but in other embodiments, the projector may not have a reflector 5. Alternatively, the projector may have multiple reflectors 5.

[0096] In embodiments 1 to 5, the first light source 11 is located in the X1 direction of the light combining element 16, and the second light source 12 is located in the Y1 direction of the light combining element 16. However, in other embodiments, the first light source 11 may be located in the Y1 direction of the light combining element 16, and the second light source 12 may be located in the X1 direction of the light combining element 16.

[0097] This is a summary of the disclosure.

[0098] The following is a summary published in this note.

[0099] (Note 1)

[0100] A single-panel projector, characterized in that,

[0101] The single-panel projector has the following features:

[0102] The first light source emits the first ray;

[0103] The second light source emits a second light that is different from the first light;

[0104] A light combining element that combines the first light and the second light to emit combined light;

[0105] An optical modulation element that modulates the synthesized light into modulated light; and

[0106] A projection lens that projects the modulated light.

[0107] Therefore, the luminous area of ​​the light source is divided by the first and second light sources, resulting in a smaller luminous area for both the first and second light sources compared to the case of a single light source. Consequently, even when the luminous area of ​​the light source is increased to make the single-panel projector brighter, the luminous areas of the first and second light sources can be kept relatively small, thus suppressing the reduction in the light efficiency of the light source (increased optical extension).

[0108] (Note 2)

[0109] The single-panel projector according to Appendix 1 is characterized in that,

[0110] The photosynthesizing element has a plate-shaped base, the base including a first surface and a second surface facing a side opposite to the first surface.

[0111] At least one of the first surface and the second surface is provided with a dielectric multilayer film.

[0112] The dielectric multilayer film allows the first light to be transmitted and the second light to be reflected, or allows the first light to be reflected and the second light to be transmitted.

[0113] Therefore, since the light-synthesizing element is plate-shaped, the space required to arrange the light-synthesizing element is smaller compared to the case where the light-synthesizing element is a dichroic prism.

[0114] (Note 3)

[0115] The single-panel projector according to Appendix 1 or 2 is characterized in that,

[0116] The first light source includes a first light-emitting element and a fluorescent element that converts the light emitted from the first light-emitting element into the first light.

[0117] The first light is yellow light.

[0118] The second light is blue light.

[0119] Therefore, the synthesized light synthesized by the light synthesizing element can be made into white light containing red, green and blue light, thus widening the color gamut of the modulated light projected by the single-panel projector.

[0120] (Note 4)

[0121] The single-panel projector according to Appendix 1 or 2 is characterized in that,

[0122] The first light source includes a first light-emitting element and a fluorescent element that converts the light emitted from the first light-emitting element into the first light.

[0123] The first light is white light.

[0124] The second light is red light.

[0125] As a result, the hue of the white light synthesized by the light-combining element is corrected. Furthermore, because the hue of the white light synthesized by the light-combining element is corrected, the white balance of the projected image projected by the single-panel projector is improved.

[0126] (Note 5)

[0127] The single-panel projector according to Appendix 1 or 2 is characterized in that,

[0128] The first light source includes a first light-emitting element and a fluorescent element that converts the light emitted from the first light-emitting element into the first light.

[0129] The first light is green light.

[0130] The second light is a mixture of blue and red light.

[0131] As a result, the intensity of the green light contained in the modulated light LA ​​projected from the single-panel projector increases, thus making the projected image a vivid image.

[0132] (Note 6)

[0133] The single-panel projector according to any one of Appendices 1 to 5 is characterized in that,

[0134] The luminous area of ​​the first light source is the same as that of the second light source.

[0135] This suppresses the color unevenness of white light as the synthesized light.

[0136] (Note 7)

[0137] The single-panel projector according to any one of Appendices 1 to 5 is characterized in that,

[0138] The luminous area of ​​the first light source is larger than that of the second light source.

[0139] The luminous efficiency of the first light based on the first light source is lower than that of the second light based on the second light source.

[0140] As a result, the luminous efficiency of the second light source with a smaller luminous area increases, thus improving the white balance of the projected image projected by the single-panel projector.

[0141] (Note 8)

[0142] The single-panel projector according to Appendix 2 is characterized in that,

[0143] The first light source includes a first light-emitting element that is an LED element emitting blue light and a second light-emitting element that is an LED element emitting green light.

[0144] The second light source has a third light-emitting element that serves as an LED element emitting red light.

[0145] Therefore, compared with the case where the light emitted from the first light-emitting element is converted into a mixed light containing blue and green light by using a fluorescent element, the spectral distribution width of the mixed light emitted from the first light source is narrower. As a result, the color gamut of the white light, which is the composite light obtained by combining the mixed light and red light, is wider.

[0146] (Note 9)

[0147] The single-panel projector according to Appendix 2 is characterized in that,

[0148] The first light source includes a first light-emitting element that is an LED element emitting blue light and a second light-emitting element that is an LED element emitting red light.

[0149] The second light source has a third light-emitting element that serves as an LED element emitting green light.

[0150] As a result, the intensity of the green light contained in the white light synthesized by the light-synthesizing element increases, and therefore the intensity of the green light contained in the modulated light projected from the single-panel projector increases, resulting in a vivid projected image.

[0151] (Postscript 10)

[0152] The single-panel projector according to Appendix 8 or 9 is characterized in that...

[0153] The total number of the second light-emitting elements is greater than the total number of the first light-emitting elements.

[0154] The second light-emitting element is disposed on the outermost periphery of the region in which the first light source is configured with the first light-emitting element and the second light-emitting element.

[0155] Therefore, even when the total number of the second light-emitting elements is greater than the total number of the first light-emitting elements, it is easy to make the first and second light-emitting elements evenly distributed in region E.

[0156] (Note 11)

[0157] The single-panel projector according to Appendix 1 is characterized in that,

[0158] The single-panel projector also has a third light source, which emits a third light different from the first and second lights.

[0159] The green light emitted by the first light source is referred to as the first light.

[0160] The second light source emits blue light as the second light source.

[0161] The third light source emits red light as the third light source.

[0162] The light-combining element comprises: a first surface facing the first light source for incident light; a second surface facing the second light source for incident light; a third surface facing the third light source for incident light; and a fourth surface emitting the combined light resulting from the combination of the first light, the second light, and the third light.

[0163] Therefore, the light emission of the first, second, and third light sources can be adjusted separately, thus making it easy to adjust the white balance of the projected image projected by the single-panel projector.

[0164] (Note 12)

[0165] The single-panel projector according to Appendix 11 is characterized in that,

[0166] The effective display area of ​​the optical modulation element has a size of 6.48mm × 11.52mm to 99.6mm × 176.8mm.

[0167] The size of the emitting surface of the first light source is 0.25mm×0.25mm to 10mm×10mm.

[0168] The size of the emitting surface of the second light source is 0.25mm×0.25mm to 10mm×10mm.

[0169] The size of the emitting surface of the third light source is 0.5mm×0.5mm to 20mm×20mm.

[0170] Therefore, it is possible to suppress the enlargement of the optical modulation element and suppress the reduction of the optical efficiency of the first, second and third light sources.

[0171] (Note 13)

[0172] The single-panel projector according to any one of Appendices 1 to 12 is characterized in that,

[0173] The single-panel projector also includes a reflector that reflects the modulated light emitted from the light modulation element toward the projection lens.

[0174] The first light source, the light combining element, the light modulation element, and the reflector are arranged along the first axis.

[0175] The second light source and the projection lens are arranged on the same side intersecting the first axis.

[0176] As a result, the size of the single-panel projector along the first axis is miniaturized.

[0177] (Note 14)

[0178] The single-panel projector according to any one of Appendices 1 to 13 is characterized in that,

[0179] The single-panel projector further comprises: a first polarizing plate disposed on the incident side of the optical modulation element to allow the synthesized light to be transmitted or reflected; and a second polarizing plate disposed on the emitting side of the optical modulation element to allow the modulated light from the optical modulation element to be transmitted.

[0180] The optical modulation element has a first sub-pixel that receives incident blue light, a second sub-pixel that receives incident green light, and a third sub-pixel that receives incident red light.

[0181] Therefore, compared with a three-panel projector that has three light modulation elements, a single-panel projector has only one light modulation element to form a full-color projected image, thus enabling miniaturization.

Claims

1. A single-panel projector, characterized in that, The single-panel projector has the following features: The first light source emits the first ray; The second light source emits a second light that is different from the first light; A light combining element that combines the first light and the second light to emit combined light; An optical modulation element that modulates the synthesized light into modulated light; and A projection lens that projects the modulated light.

2. The single-panel projector according to claim 1, characterized in that, The photosynthesizing element has a plate-shaped base, the base including a first surface and a second surface facing a side opposite to the first surface. At least one of the first surface and the second surface is provided with a dielectric multilayer film. The dielectric multilayer film allows the first light to be transmitted and the second light to be reflected, or allows the first light to be reflected and the second light to be transmitted.

3. The single-panel projector according to claim 1 or 2, characterized in that, The first light source includes a first light-emitting element and a fluorescent element that converts the light emitted from the first light-emitting element into the first light. The first light is yellow light. The second light is blue light.

4. The single-panel projector according to claim 1 or 2, characterized in that, The first light source includes a first light-emitting element and a fluorescent element that converts the light emitted from the first light-emitting element into the first light. The first light is white light. The second light is red light.

5. The single-panel projector according to claim 1 or 2, characterized in that, The first light source includes a first light-emitting element and a fluorescent element that converts the light emitted from the first light-emitting element into the first light. The first light is green light. The second light is a mixture of blue and red light.

6. The single-panel projector according to claim 1, characterized in that, The luminous area of ​​the first light source is the same as that of the second light source.

7. The single-panel projector according to claim 1, characterized in that, The luminous area of ​​the first light source is larger than that of the second light source. The luminous efficiency of the first light based on the first light source is lower than that of the second light based on the second light source.

8. The single-panel projector according to claim 2, characterized in that, The first light source includes a first light-emitting element that is an LED element emitting blue light and a second light-emitting element that is an LED element emitting green light. The second light source has a third light-emitting element that serves as an LED element emitting red light.

9. The single-panel projector according to claim 2, characterized in that, The first light source includes a first light-emitting element that is an LED element emitting blue light and a second light-emitting element that is an LED element emitting red light. The second light source has a third light-emitting element that serves as an LED element emitting green light.

10. The single-panel projector according to claim 8 or 9, characterized in that, The total number of the second light-emitting elements is greater than the total number of the first light-emitting elements. The second light-emitting element is disposed on the outermost periphery of the region in which the first light source is configured with the first light-emitting element and the second light-emitting element.

11. The single-panel projector according to claim 1, characterized in that, The single-panel projector also has a third light source, which emits a third light different from the first and second lights. The green light emitted by the first light source is referred to as the first light. The second light source emits blue light as the second light source. The third light source emits red light as the third light source. The light-combining element comprises: a first surface facing the first light source for incident light; a second surface facing the second light source for incident light; a third surface facing the third light source for incident light; and a fourth surface emitting the combined light resulting from the combination of the first light, the second light, and the third light.

12. The single-panel projector according to claim 11, characterized in that, The effective display area of ​​the optical modulation element has a size of 6.48mm × 11.52mm to 99.6mm × 176.8mm. The size of the emitting surface of the first light source is 0.25mm×0.25mm to 10mm×10mm. The size of the emitting surface of the second light source is 0.25mm×0.25mm to 10mm×10mm. The size of the emitting surface of the third light source is 0.5mm×0.5mm to 20mm×20mm.

13. The single-panel projector according to claim 1, characterized in that, The single-panel projector also includes a reflector that reflects the modulated light emitted from the light modulation element toward the projection lens. The first light source, the light combining element, the light modulation element, and the reflector are arranged along the first axis. The second light source and the projection lens are arranged on the same side intersecting the first axis.

14. The single-panel projector according to claim 1, characterized in that, The single-panel projector also includes: a first polarizing plate, which is disposed on the incident side of the light modulation element to transmit or reflect the synthesized light; And a second polarizing plate, which is disposed on the emission side of the optical modulation element, so that the modulated light from the optical modulation element is transmitted. The optical modulation element has a first sub-pixel that receives incident blue light, a second sub-pixel that receives incident green light, and a third sub-pixel that receives incident red light.

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