Projection equipment
The projection device uses a dichroic prism with angle limiting filters and light-absorbing members to control light emission from multiple self-luminous display devices, reducing stray light and enhancing image quality for compact, high-quality projection systems.
Patent Information
- Application Number
- JP2022043559
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2022-03-18
- Publication Date
- 2026-01-16
- Estimated Expiration
- 2042-03-18
AI Technical Summary
Light emitted from self-luminous display devices is diffused and reflected within a dichroic prism, leading to stray light, which degrades image quality.
A projection device comprising a dichroic prism with specific configurations, including angle limiting filters and light-absorbing members, to control and direct light emission from multiple self-luminous display devices, reducing stray light and enhancing image quality.
The solution effectively minimizes stray light, resulting in a compact, high-quality projection system with improved image brightness and flexibility in installation, suitable for mobile devices and wearable applications.
Smart Images

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Abstract
Description
[Technical Field]
[0001] The present invention relates to a projection device. [Background technology]
[0002] Patent Document 1 describes a display device in which light emitted from three organic electroluminescent panels is combined using a dichroic prism and projected onto a screen or the like using a projection optical system. Each organic electroluminescent panel is a light-emitting panel equipped with organic electroluminescent elements and is a self-luminous display device. The dichroic prism has a rectangular parallelepiped shape with a first incident surface, a second incident surface, a third incident surface, and an exit surface, and has side surfaces, a top surface, and a bottom surface. The three self-luminous display devices are a first self-luminous display device facing the first incident surface, which is the back surface of the dichroic prism; a second self-luminous display device facing the second incident surface, which is one side surface of the dichroic prism; and a third self-luminous display device facing the third incident surface, which is the other side surface of the dichroic prism. The light emitted from each self-luminous display device is superimposed by passing through the dichroic prism and then exits from the exit surface, which is the front surface of the dichroic prism.
[0003] Patent Document 2 describes that a display panel having aligned pixel light sources has a fairly wide divergence angle, although the divergence angle can be reduced by using microlenses. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-174515 [Patent Document 2] US Patent Application Publication No. 2007 / 0242161 Summary of the Invention [Problem to be solved by the invention]
[0005] The light emitted from each self-luminous display device is diffused while passing through the dichroic prism, and some of the projected light is reflected by the ceiling, bottom, or sides before reaching the exit surface of the dichroic prism. This light becomes stray light after being emitted from the exit surface of the dichroic prism. [Means for solving the problem]
[0006] In order to solve the above-mentioned problems, the projection device of the present invention is characterized by comprising: a dichroic prism having first, second, third, and fourth surfaces and emitting synthesized image light from the fourth surface; a first self-luminous display device having a plurality of first light-emitting elements that emit light of a first wavelength and emitting first image light onto the first surface using light of the first wavelength; a second self-luminous display device having a plurality of second light-emitting elements that emit light of a second wavelength and emitting second image light onto the second surface using light of the second wavelength; a third self-luminous display device having a plurality of third light-emitting elements that emit light of a third wavelength and emitting third image light onto the third surface using light of the third wavelength; a projection optical system that projects the image light from the dichroic prism onto a projection target; a control unit that controls the first self-luminous display device, the second self-luminous display device, and the third self-luminous display device; and a power supply unit that supplies power to the first self-luminous display device, the second self-luminous display device, the third self-luminous display device, and the control unit. [Brief explanation of the drawings]
[0007] [Figure 1] 1 is a schematic diagram of a projection device according to a first embodiment. [Figure 2] FIG. 1 is a schematic front view of a self-luminous display device. [Figure 3] FIG. 1 is a schematic side view of a self-luminous display device. [Figure 4] FIG. 1 is a schematic diagram of an example of a projection system including a projection device. [Figure 5] FIG. 1 is a schematic diagram of another example of a projection system including a projection device. [Figure 6]10 is a schematic side cross-sectional view of yet another example of a projection system including a projection device. [Figure 7] FIG. 7 is a schematic horizontal cross-sectional view of the projection system corresponding to FIG. 6. [Figure 8] FIG. 10 is an explanatory diagram of a projection device according to a second embodiment. [Figure 9] FIG. 10 is an explanatory diagram of an angle limiting filter. [Figure 10] FIG. 10 is a diagram illustrating another example of an angle limiting filter. [Figure 11] FIG. 10 is a diagram illustrating a projection device according to a third embodiment. [Figure 12] 10 is a diagram illustrating a light absorbing member provided on a fourth surface of the dichroic prism. FIG. [Figure 13] FIG. 10 is a diagram illustrating a projection device according to a fourth embodiment. [Figure 14] 10A and 10B are diagrams illustrating a dichroic prism according to a fourth embodiment. [Figure 15] FIG. 10 is a diagram illustrating a projection device unit according to a fifth embodiment. [Figure 16] 10A and 10B are diagrams illustrating a dichroic prism according to a fifth embodiment. [Figure 17] FIG. 10 is a diagram illustrating a projection device according to a sixth embodiment. [Figure 18] FIG. 1 is an explanatory diagram showing a self-luminous display device having an in-plane angular distribution as viewed from the front. [Figure 19] 1 is an explanatory diagram showing a self-luminous display device having an in-plane angular distribution as viewed from the side; [Figure 20] FIG. 10 is a schematic diagram of a projection device in which the self-luminous display device has a luminous intensity distribution. [Figure 21] FIG. 1 is an explanatory diagram of a self-luminous display device having a luminous intensity distribution. [Figure 22] FIG. 1 is a schematic diagram of an image forming section using a Philips prism. DETAILED DESCRIPTION OF THE INVENTION
[0008] A projection device according to an embodiment of the present invention will be described below with reference to the drawings. [Embodiment 1] A projection device according to a first embodiment will now be described. FIG. 1 is a schematic diagram of the projection device according to the first embodiment. As shown in FIG. 1, the projection device 1 according to the first embodiment includes an image forming unit 2 that emits image light L, a control unit 4 that controls the image forming unit 2, a projection optical system 3 that enlarges the image light L and projects it onto a screen S, which is the projection target, to form an image, and a power supply unit 5. Each unit is housed in or installed in a housing 8. The power supply unit 5 can be powered by a battery or the like, and the image forming unit 2 does not require a separate light source and can be separated from the other units. This configuration makes it possible to realize a projection system that is compact, lightweight, and high-quality, and that produces bright, visible images.
[0009] The image forming unit 2 includes a first self-luminous display device 21, a second self-luminous display device 22, and a third self-luminous display device 23. In this example, each self-luminous display device is a display panel having a light-emitting element for each pixel. The light-emitting elements are OLEDs (Organic Light-Emitting Diodes). Each self-luminous display device may also be a μLED. Each self-luminous display device is made of the same material. The image forming unit 2 also includes a dichroic prism 10 for combining first image light LG of a first wavelength emitted from the first self-luminous display device 21, second image light LB of a second wavelength emitted from the second self-luminous display device 22, and third image light LR of a third wavelength emitted from the third self-luminous display device 23.
[0010] The control unit 4 includes an image processing unit 6 to which an image signal such as a video signal is input, and a display driving unit 7 that drives and controls the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23 based on the image signal output from the image processing unit 6. The image processing unit 6 converts the input image signal into an image signal including the tone of each color. The display driving unit 7 operates the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23 based on the projection image signal of each color output from the image processing unit 6. When the first image light LG, the second image light LB, and the third image light LR are combined by the dichroic prism 10, an image light L corresponding to the image signal is formed. In this example, the first image light LG is green, the second image light LB is blue, and the third image light LR is red. The first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23 emit green, blue, and red image light, respectively.
[0011] The self-luminous display devices surround the dichroic prism 10 from three directions. The projection optical system 3 is located on the opposite side of the first self-luminous display device 21, with the dichroic prism 10 sandwiched therebetween.
[0012] In the following description, three mutually orthogonal directions are referred to as the X-axis direction, the Y-axis direction, and the Z-axis direction. FIG. 1 shows the image forming unit 2 as viewed from the Z-axis direction. The X-axis direction is the direction in which the first self-luminous display device 21, the dichroic prism 10, and the projection optical system 3 are arranged. The Y-direction is the direction in which the second self-luminous display device 22, the dichroic prism 10, and the third self-luminous display device 23 are arranged. In the X-axis direction, the side of the dichroic prism 10 where the first self-luminous display device 21 is located is referred to as the X1 direction, and the side where the projection optical system 3 is located is referred to as the X2 direction. In the Y-axis direction, the side of the dichroic prism 10 where the second self-luminous display device 22 is located is referred to as the Y2 direction, and the side where the third self-luminous display device 23 is located is referred to as the Y1 direction.
[0013] The dichroic prism 10 has a rectangular parallelepiped shape and is made up of four triangular prisms. The dichroic prism 10 has a first surface 11, a second surface 12, a third surface 13, a fourth surface 14, a top surface, and a bottom surface. The first surface 11 faces the fourth surface 14, and the second surface 12 faces the third surface 13. The second surface 12 and the third surface 13 are provided between the first surface 11 and the fourth surface. The other two opposing surfaces are the top surface and the bottom surface. The first surface 11 is located on the X2-direction side of the first self-luminous display device 21. The first surface 11 faces the first self-luminous display device 21 in the X-axis direction. The second surface 12 is located on the Y1-direction side of the second self-luminous display device 22. The second surface 12 faces the second self-luminous display device 22 in the Y-axis direction. The third surface 13 is located on the Y2-direction side of the third self-luminous display device 23. The third surface 13 faces the third self-luminous display device 23 in the Y-axis direction. The fourth surface 14 is located on the X1-direction side of the projection optical system 3. The fourth surface 14 faces the projection optical system 3 in the X-axis direction. The four triangular prisms are each a triangular pillar extending in the Z-axis direction, and are joined at their joining surfaces to form a cubic dichroic prism 10.
[0014] The dichroic prism 10 has a first dichroic film 16 and a second dichroic film 17. The first dichroic film 16 and the second dichroic film 17 are arranged so as to intersect with each other at a 90° angle. The first dichroic film 16 and the second dichroic film 17 are each provided on the bonding surface where two triangular prisms are bonded to each other. The first dichroic film 16 is formed so as to be inclined from the X1 direction to the Y2 direction. The second dichroic film 17 is formed so as to be inclined from the X1 direction to the Y1 direction.
[0015] The first self-luminous display device 21 emits first image light LG along the X2 direction through the first surface 11 toward the first dichroic film 16 and the second dichroic film 17. The second self-luminous display device 22 emits second image light LB along the Y1 direction through the second surface 12 toward the first dichroic film 16. The third self-luminous display device 23 emits third image light LR along the Y2 direction through the third surface 13 toward the second dichroic film 17.
[0016] 2 is a schematic front view of the light-emitting display surface of the first self-luminous display device 21 as viewed in the X1 direction. FIG. 3 is a schematic side view of the side surface of the first self-luminous display device 21 as viewed in the Y2 direction. As shown in FIGS. 2 and 3, the first self-luminous display device 21 includes a substrate 24 and a plurality of light-emitting elements 25 arranged in a matrix on the substrate 24. The optical axis N of each light-emitting element 25 is perpendicular to the substrate 24. That is, the optical axes N of the light-emitting elements 25 are parallel to each other. Each light-emitting element 25 emits light. The second self-luminous display device 22 and the third self-luminous display device 23 have a similar configuration.
[0017] When light is emitted from the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23, the first dichroic film 16 transmits the first image light LG and the third image light LR. The first dichroic film 16 also reflects the second image light LB in the X2 direction. The second dichroic film 17 transmits the first image light LG and the second image light LB. The second dichroic film 17 also reflects the third image light LR in the X2 direction.
[0018] The first image light LG from the first self-luminous display device 21 and the second image light LB from the second self-luminous display device 22 are combined by the first dichroic film 16 and directed in the X2 direction. The first image light LG from the first self-luminous display device 21 and the third image light LR from the third self-luminous display device 23 are combined by the second dichroic film 17. The combined lights from the first dichroic film 16 and the second dichroic film 17 overlap to become image light L directed in the X2 direction. The image light L enters the projection optical system 3.
[0019] The display panel is a self-luminous display device capable of emitting high-brightness light, eliminating the need for a separate light source or a large power supply unit to supply power to the light source, making it possible to reduce the overall size and weight of the projection device 1. For example, as shown in Figure 4, it is possible to incorporate the projection device 1 into a thin mobile device MD such as a smartphone equipped with various devices such as a camera CA to project images.
[0020] 5, the projection device 1 can be easily installed in the glasses GA worn by the observer or wearer US, and an image can be projected into real space ahead of the line of sight of the observer or wearer US. Furthermore, by adding a switching mechanism CH that can project an image from the projection device 1 onto the eyeglass lenses GL of the glasses GA, the glasses GA can be configured as a head-up display.
[0021] 6 and 7, the projection device 1 can be easily installed relative to the viewer M, allowing for greater flexibility in installation. The projection device 1 can be easily installed on the seat CM of the viewer M or on the ceiling CL, allowing the viewer M to view the image using the wall WA as a screen SC. The seat CM can also be the driver's seat of a car.
[0022] In addition, in the mobile device MD, the camera CA can be used to detect the position of the screen SC and even sense the shape of the projection surface, making it possible to improve the quality of the displayed image.It is also possible to incorporate a photodetector into a self-luminous display device, making it possible to achieve the same function as the camera CA.
[0023] [Embodiment 2] Next, a second embodiment will be described. Fig. 8 is an explanatory diagram of a projection device of the second embodiment. Fig. 9 is an explanatory diagram of an angle limiting filter. A projection device 1A of the second embodiment differs from the projection device 1 of the first embodiment in that it is equipped with three angle limiting filters. Note that other configurations of the projection device 1A of the second embodiment are the same as those of the projection device 1 of the first embodiment, so corresponding configurations are given the same reference numerals and their description will be omitted.
[0024] 8, in the image forming unit 2, the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23 surround the dichroic prism 10 from three directions. The projection optical system 3 is located on the opposite side of the first self-luminous display device 21, with the dichroic prism 10 sandwiched therebetween.
[0025] In this example, the image forming unit 2 has angle-limiting filters 30 arranged between the first self-luminous display device 21 and the first surface 11, between the second self-luminous display device 22 and the second surface 12, and between the third self-luminous display device 23 and the third surface 13.
[0026] 9, the angle limiting filter 30 includes a glass plate 31 and a resin lattice structure 32 provided on one surface of the glass plate 31. The lattice structure 32 narrows the light distribution angle of light emitted from each light-emitting element 25 in front of each light-emitting element 25 of the self-luminous display device. This narrows the light distribution angle of the first image light LG of the first self-luminous display device 21. The light distribution angle of the second image light LB of the second self-luminous display device 22. The light distribution angle of the third image light LR of the third self-luminous display device 23 is also narrowed.
[0027] Fig. 10 shows another example of the angle limiting filter 30. As shown in Fig. 10, the angle limiting filter 30 of this example includes a plurality of lenses 35 arranged in a matrix. The plurality of lenses 35 refracts the light emitted from each light-emitting element 25 of each self-luminous display device, thereby narrowing the light distribution angle.
[0028] According to this example, the image light emitted from each of the three self-luminous display devices is overlapped by two dichroic films and emitted from the fourth surface 14 of the dichroic prism 10. Here, peripheral light of each image light emitted from each self-luminous display device is diffused while passing through the dichroic prism 10 and is reflected by other surfaces of the dichroic prism before reaching the fourth surface 14. Furthermore, such peripheral light becomes stray light after emitting from the fourth surface 14 of the dichroic prism 10. In contrast, in this example, an angle limiting filter 30 is provided between each self-luminous display device and the dichroic prism 10 to narrow the light distribution angle of the image light emitted from each light-emitting element 25 of each self-luminous display device. Therefore, in each image light emitted from each of the three self-luminous display devices, peripheral light reflected by other surfaces within the dichroic prism 10 before reaching the fourth surface 14 of the dichroic prism 10 can be reduced. Therefore, the occurrence of stray light due to reflection within the dichroic prism 10 can be prevented.
[0029] [Embodiment 3] Next, a third embodiment will be described. Fig. 11 is a diagram illustrating a projection device of the third embodiment. Fig. 12 is a diagram illustrating a light-absorbing member provided on the fourth surface of the dichroic prism. A projection device 1B of the third embodiment differs from the projection device 1 of the first embodiment in the configuration of the dichroic prism 10. Note that other configurations of the projection device 1B of the third embodiment are the same as those of the projection device 1 of the first embodiment, so the same reference numerals are used for corresponding configurations and their description will be omitted.
[0030] 11, in the image forming unit 2, the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23 surround the dichroic prism 10 from three directions. The projection optical system 3 is located on the opposite side of the first self-luminous display device 21, with the dichroic prism 10 sandwiched therebetween.
[0031] 11 and 12, a frame-shaped light absorbing member 40 is provided on the outer peripheral edge of the fourth surface 14 of the dichroic prism 10. The light absorbing member 40 absorbs the first image light LG, the second image light LB, and the third image light LR.
[0032] According to this example, the image light emitted from each of the three spontaneous-luminous display devices is overlapped by two dichroic films and exits from the fourth surface 14 of the dichroic prism 10. The peripheral light of each projection light emitted from each of the self-luminous display devices is diffused while passing through the dichroic prism 10 and is reflected by other surfaces of the dichroic prism before reaching the fourth surface 14. Furthermore, this peripheral light becomes stray light after exiting the fourth surface 14 of the dichroic prism 10. In contrast, in this example, a frame-shaped light-absorbing member 40 is provided on the outer periphery of the fourth surface 14. This prevents light from being reflected by other surfaces within the dichroic prism 10 and reaching the fourth surface 14 of the dichroic prism 10 from exiting the fourth surface 14. This prevents the peripheral light of the image light L from entering the projection optical system 3 and becoming stray light.
[0033] This example may also include the three angle limiting filters of embodiment 2. In this way, in each of the image lights emitted from the three spontaneous light-emitting display devices, it is possible to reduce the amount of peripheral light reflected by other surfaces within the dichroic prism 10 before reaching the fourth surface 14 of the dichroic prism 10. This makes it possible to prevent the generation of stray light due to reflection within the dichroic prism 10.
[0034] [Embodiment 4] Next, a fourth embodiment will be described. Fig. 13 is a diagram illustrating a projection device of the fourth embodiment. Fig. 14 is a diagram illustrating a dichroic prism of the fourth embodiment. A projection device 1C of the fourth embodiment differs from the projection device 1 of the first embodiment in the configuration of the dichroic prism 10. Note that other configurations of the projection device 1C of the fourth embodiment are the same as those of the projection device 1 of the first embodiment, so the same reference numerals are used for corresponding configurations and their description will be omitted.
[0035] 13, in the image forming unit 2, the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23 surround the dichroic prism 10 from three directions. The projection optical system 3 is located on the opposite side of the first self-luminous display device 21, with the dichroic prism 10 sandwiched therebetween.
[0036] 13 and 14 , the optical axis direction along the optical axis O of the image light L emerging from the fourth surface 14 of the dichroic prism 10 coincides with the X-axis direction. That is, the first surface 11 and the fourth surface 14 of the dichroic prism 10 face each other in the optical axis direction. An annular groove 50 surrounding the optical axis O is provided on the annular outer peripheral surface of the dichroic prism 10 surrounding the optical axis O, at a position closer to the fourth surface 14 than the first surface 11.
[0037] According to this example, the image lights emitted from the three self-luminous display devices are overlapped by two dichroic films and emitted from the fourth surface 14 of the dichroic prism 10. Here, peripheral light of the image lights emitted from each self-luminous display device is diffused while passing through the dichroic prism 10 and is reflected by other surfaces of the dichroic prism 10 before reaching the fourth surface 14. Furthermore, such peripheral light becomes stray light after being emitted from the fourth surface 14 of the dichroic prism 10. In contrast, in this example, an annular groove 50 surrounding the optical axis O is provided on the annular outer peripheral surface of the dichroic prism 10 surrounding the optical axis O, at a position closer to the fourth surface 14 than the first surface 11. As a result, in each of the image lights emitted from the three spontaneous light-emitting display devices, light that is reflected by another surface within the dichroic prism 10 before reaching the fourth surface 14 of the dichroic prism 10 is prevented by the annular groove 50 from reaching the fourth surface 14. Therefore, peripheral light of the image light L does not enter the projection optical system 3, and can be prevented from becoming stray light.
[0038] This example may also include the three angle limiting filters of embodiment 2. In this way, in each of the image lights emitted from the three spontaneous light-emitting display devices, it is possible to reduce the amount of peripheral light reflected by other surfaces within the dichroic prism 10 before reaching the fourth surface 14 of the dichroic prism 10. This makes it possible to prevent the generation of stray light due to reflection within the dichroic prism 10.
[0039] Also, in this example, the light absorbing member 40 of the third embodiment may be provided. Therefore, it is possible to further prevent peripheral light of the image light L from entering the projection optical system 3 and becoming stray light.
[0040] [Embodiment 5] Next, a fifth embodiment will be described. Fig. 15 is a diagram illustrating a projection device of the fifth embodiment. Fig. 16 is a diagram illustrating a dichroic prism of the fifth embodiment. A projection device 1D of the fifth embodiment differs from the projection device 1 of the first embodiment in the configuration of the dichroic prism 10. Note that other configurations of the projection device 1D of the fifth embodiment are the same as those of the projection device 1 of the first embodiment, so the same reference numerals are used for corresponding configurations and their description will be omitted.
[0041] 15, in the image forming unit 2, the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23 surround the dichroic prism 10 from three directions. The projection optical system 3 is located on the opposite side of the first self-luminous display device 21, with the dichroic prism 10 sandwiched therebetween.
[0042] 15 and 16 , the optical axis direction along the optical axis O of the image light L emerging from the fourth surface 14 of the dichroic prism 10 coincides with the X-axis direction. That is, the first surface 11 and the fourth surface 14 of the dichroic prism 10 face each other in the optical axis direction. An annular groove 50 surrounding the optical axis O is provided on the annular outer peripheral surface of the dichroic prism 10 surrounding the optical axis O, at a position closer to the fourth surface 14 than the first surface 11.
[0043] A light absorbing member 60 is provided in the annular groove 50. The light absorbing member 60 absorbs the first image light LG, the second image light LB, and the third image light LR.
[0044] According to this example, the image lights emitted from the three self-luminous display devices are overlapped by two dichroic films and emitted from the fourth surface 14 of the dichroic prism 10. Here, peripheral light of the image lights emitted from each self-luminous display device is diffused while passing through the dichroic prism 10 and is reflected by other surfaces of the dichroic prism 10 before reaching the fourth surface 14. Furthermore, such peripheral light becomes stray light after being emitted from the fourth surface 14 of the dichroic prism 10. In contrast, in this example, an annular groove 50 surrounding the optical axis O is provided on the annular outer peripheral surface of the dichroic prism 10 surrounding the optical axis O, at a position closer to the fourth surface 14 than the first surface 11. As a result, in each of the image lights emitted from the three spontaneous light-emitting display devices, light that is reflected by another surface within the dichroic prism 10 before reaching the fourth surface 14 of the dichroic prism 10 is prevented by the annular groove 50 from reaching the fourth surface 14. Therefore, peripheral light of the image light L does not enter the projection optical system 3, and can be prevented from becoming stray light.
[0045] In this example, a light-absorbing member 60 is provided in the annular groove 50. The light-absorbing member 60 absorbs the first image light LG, the second image light LB, and the third image light LR. As a result, in each of the image lights emitted from the three spontaneous light-emitting display devices, light that is reflected by another surface within the dichroic prism 10 before reaching the fourth surface 14 of the dichroic prism 10 is prevented by the light-absorbing member 60 from reaching the fourth surface 14. This further prevents peripheral light of the image light L from entering the projection optical system 3 and becoming stray light.
[0046] This example may also include the three angle limiting filters of embodiment 2. In this way, in each of the image lights emitted from the three spontaneous light-emitting display devices, it is possible to reduce the amount of peripheral light reflected by other surfaces within the dichroic prism 10 before reaching the fourth surface 14 of the dichroic prism 10. This makes it possible to prevent the generation of stray light due to reflection within the dichroic prism 10.
[0047] Also, in this example, the light absorbing member 40 of the third embodiment may be provided. Therefore, it is possible to further prevent peripheral light of the image light L from entering the projection optical system 3 and becoming stray light.
[0048] [Embodiment 6] Next, a sixth embodiment will be described. Fig. 17 is a diagram illustrating a projection device of the sixth embodiment. A projection device 1E of the sixth embodiment differs from the projection device 1 of the first embodiment in the configuration of the dichroic prism 10. Since the other configurations of the projection device 1E of the sixth embodiment are the same as those of the projection device 1 of the first embodiment, the same reference numerals are used for corresponding configurations and their description will be omitted.
[0049] 17, in the image forming unit 2, the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23 surround the dichroic prism 10 from three directions. The projection optical system 3 is located on the opposite side of the first self-luminous display device 21, with the dichroic prism 10 sandwiched therebetween.
[0050] The dichroic prism 10 has a first dichroic film 16 and a second dichroic film 17. The first dichroic film 16 and the second dichroic film 17 are arranged so as to intersect with each other at a 90° angle. The first dichroic film 16 and the second dichroic film 17 are provided on the bonding surface where four triangular prisms are bonded to each other. The first dichroic film 16 is tilted in the Y2 direction toward the X1 direction. The second dichroic film 17 is tilted in the Y1 direction toward the X1 direction.
[0051] The first dichroic film 16 is provided with a frame-shaped first light absorbing layer 18 that absorbs the peripheral light of the first image light LG and the peripheral light of the second image light LB. Note that the first light absorbing layer 18 may absorb the first image light LG, the second image light LB, and the third image light LR.
[0052] The second dichroic film 17 is provided with a frame-shaped second light absorbing layer 19 that absorbs the peripheral light of the first image light LG and the peripheral light of the third image light LR. Note that the second light absorbing layer 19 may absorb the first image light LG, the second image light LB, and the third image light LR.
[0053] According to this example, the image lights emitted from the three self-luminous display devices are overlapped by two dichroic films and emitted from the fourth surface 14 of the dichroic prism 10. Here, peripheral light of each image light emitted from each self-luminous display device is diffused while passing through the dichroic prism 10 and is reflected by another surface of the dichroic prism 10 before reaching the fourth surface 14. Furthermore, such peripheral light becomes stray light after being emitted from the fourth surface 14 of the dichroic prism 10. In contrast, in this example, the first dichroic film 16 is provided with a frame-shaped first light-absorbing layer 18 that absorbs the peripheral light of the first image light LG and the peripheral light of the second image light LB. Furthermore, the second dichroic film 17 is provided with a frame-shaped second light-absorbing layer 19 that absorbs the peripheral light of the first image light LG and the peripheral light of the third image light LR. Therefore, in each of the image lights emitted from the three spontaneous light-emitting display devices, it is possible to reduce the amount of ambient light reflected by other surfaces within the dichroic prism 10 before reaching the fourth surface 14 of the dichroic prism 10. This makes it possible to prevent the generation of stray light due to reflection within the dichroic prism 10.
[0054] This example may also include the three angle limiting filters of embodiment 2. In this way, in each of the image lights emitted from the three spontaneous light-emitting display devices, it is possible to reduce the amount of peripheral light reflected by other surfaces within the dichroic prism 10 before reaching the fourth surface 14 of the dichroic prism 10. This makes it possible to prevent the generation of stray light due to reflection within the dichroic prism 10.
[0055] Also, in this example, the light absorbing member 40 of the third embodiment may be provided. Therefore, it is possible to further prevent peripheral light of the image light L from entering the projection optical system 3 and becoming stray light.
[0056] This example may also include the annular groove 50 of the fourth embodiment. Also, the light absorbing member 60 of the fifth embodiment may also be included. As a result, in each of the image lights emitted from the three spontaneously luminous display devices, light that is reflected by other surfaces within the dichroic prism 10 before reaching the fourth surface 14 of the dichroic prism 10 is prevented from reaching the fourth surface 14 by the annular groove 50 and the light absorbing member 60. This further prevents peripheral light of the image light L from entering the projection optical system 3 and becoming stray light.
[0057] [Variation 1] In the third to sixth embodiments, the first, second, and third self-luminous display devices 21, 22, and 23 may have an in-plane angular distribution. Fig. 18 is an explanatory diagram showing a self-luminous display device having an in-plane angular distribution as viewed from the front. Fig. 19 is an explanatory diagram showing a self-luminous display device having an in-plane angular distribution as viewed from the side.
[0058] 18 and 19, each self-luminous display device includes a substrate 24 and a plurality of light-emitting elements 25 arranged in a matrix on the substrate. Of the light-emitting elements 25, a plurality of inner light-emitting elements 25A arranged in a matrix in the central portion have optical axes N perpendicular to the substrate. Of the light-emitting elements 25, a plurality of outer light-emitting elements 25B arranged in a frame shape on the outer periphery of the inner light-emitting elements 25A have optical axes N inclined toward the inner periphery.
[0059] In the third embodiment, when a self-luminous display device having an in-plane angular distribution is used for each of the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23, the amount of light absorbed by the light-absorbing member 40 in the peripheral light of the image light of each self-luminous display device can be reduced. Therefore, it is possible to reduce the difference in the amount of light between the peripheral and central portions of the image light L. In the fourth embodiment, when a self-luminous display device having an in-plane angular distribution is used for each of the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23, the amount of light absorbed by the annular groove 50 in the peripheral light of the image light of each self-luminous display device can be reduced. Therefore, it is possible to reduce the difference in the amount of light between the peripheral and central portions of the image light L.
[0060] In the fifth embodiment, when the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23 each have an in-plane angular distribution, the amount of light absorbed by the annular groove 50 and the light-absorbing member 60 in the peripheral light of the image light of each self-luminous display device can be reduced. This makes it possible to reduce the difference in the amount of light between the peripheral and central portions of the image light L. In the sixth embodiment, when the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23 each have an in-plane angular distribution, the amount of light absorbed by the first light-absorbing layer 18 and the second light-absorbing layer 19 in the peripheral light of the image light of each self-luminous display device can be reduced. This makes it possible to reduce the difference in the amount of light between the peripheral and central portions of the image light L.
[0061] [Variation 2] In the third to sixth embodiments, the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23 may have a light-emitting intensity distribution. Fig. 20 is a schematic diagram of a projection device in which the self-luminous display devices have a light-emitting intensity distribution. Fig. 21 is an explanatory diagram of a self-luminous display device having a light-emitting intensity distribution.
[0062] As shown in Fig. 20, in the projection device 1F of this example, the display drive unit 7 of the control unit 4 includes a light emission intensity control unit. As shown in Fig. 21, the light emission intensity control unit increases the light emission intensity of the plurality of outer periphery light emitting elements 25B arranged in a frame shape on the outer periphery of the plurality of light emitting elements 25 in each self-luminous display device, more than the light emission intensity of the plurality of inner light emitting elements 25A arranged inside the outer periphery light emitting elements 25B. As a result, the image light from each self-luminous display device has a greater amount of peripheral light.
[0063] Therefore, in the third embodiment, if the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23 each have an emission intensity distribution, it is possible to suppress a difference in the amount of light between the peripheral and central parts of the image light L when a portion of the peripheral light of the image light of each self-luminous display device is absorbed by the light-absorbing member 40. In the fourth embodiment, if the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23 each have an emission intensity distribution, it is possible to suppress a difference in the amount of light between the peripheral and central parts of the image light L when a portion of the peripheral light of the image light of each self-luminous display device is absorbed by the annular groove 50.
[0064] In the fifth embodiment, if the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23 each have an emission intensity distribution, it is possible to suppress a difference in the amount of light between the peripheral and central portions of the image light L when a portion of the peripheral light of the image light of each self-luminous display device is absorbed by the annular groove 50 and the light-absorbing member 60. In the sixth embodiment, if the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23 each have an emission intensity distribution, it is possible to suppress a difference in the amount of light between the peripheral and central portions of the image light L when a portion of the peripheral light of the image light of each self-luminous display device is absorbed by the first light-absorbing layer 18 and the second light-absorbing layer 19.
[0065] [Other embodiments] In each embodiment and modification, the dichroic prism may be a Philips prism. Fig. 22 is a schematic diagram of an image forming section using a Philips prism.
[0066] 22, in the image forming unit 2, the first self-luminous display device 21, the second self-luminous display device 22, and the third self-luminous display device 23 surround the Philips prism 100 from three directions. The projection optical system 3 is located on the opposite side of the first self-luminous display device 21, with the Philips prism 100 sandwiched therebetween.
[0067] The Philips prism 100 comprises a trapezoidal first prism 100A, a triangular second prism 100B, and a triangular third prism 100C. The Philips prism 100 has a first surface 11, a fourth surface 14 opposite the first surface 11, a second surface 12 provided between the first surface 11 and the fourth surface, and a third surface opposite the second surface 12. The first surface 11 is located on the X2-direction side of the first self-luminous display device 21. The first surface 11 faces the first self-luminous display device 21 in the X-axis direction. The second surface 12 is located on the Y1-direction side of the second self-luminous display device 22. The second surface 12 faces the second self-luminous display device 22, tilting toward the Y1 direction toward the X1 direction. The third surface 13 is located on the Y2-direction side of the third self-luminous display device 23. The third surface 13 is tilted in the Y2 direction toward the X1 direction and faces the third self-luminous display device 23. The fourth surface 14 is located on the X1 direction side of the projection optical system 3. The fourth surface 14 faces the projection optical system 3 in the X-axis direction. The fourth surface 14 is tilted at an angle of 45° or more with respect to the third surface 13.
[0068] The Philips prism 100 has a first dichroic film 16 and a second dichroic film 17. The first dichroic film 16 and the second dichroic film 17 are spaced apart. That is, the first dichroic film 16 is provided on a first bonding surface 101 where the first prism 100A and the second prism 100B are bonded to each other. The second dichroic film 17 is provided on a second bonding surface 102 where the second prism 100B and the third prism 100C are bonded to each other. The first dichroic film 16 is tilted toward the X1 direction toward the Y2 direction. The second dichroic film 17 is tilted toward the X1 direction toward the Y1 direction. The second dichroic film 17 is tilted at an angle of 45° or more with respect to the second surface 12.
[0069] The first self-luminous display device 21 emits first image light LG toward the first dichroic film 16 and the second dichroic film 17. The second self-luminous display device 22 emits second image light LB toward the first dichroic film 16. At this time, the second image light LB is totally reflected by the second dichroic film 17 and directed toward the first dichroic film 16. The third self-luminous display device 23 emits third image light LR toward the second dichroic film 17. At this time, the third image light LR is totally reflected by the fourth surface 14 and directed toward the second dichroic film 17.
[0070] The first dichroic film 16 transmits the first image light LG and reflects the second image light LB, and emits a first combined light L1 obtained by combining the first image light LG and the second image light LB. The second dichroic film 17 transmits the first combined light L1 and reflects the third image light LR. The first combined light L1 and the third image light LR overlap. The overlapped image light L is emitted in the X2 direction from the fourth surface 14. The image light L is incident on the projection optical system 3.
[0071] In each of the embodiments and modifications, even when the Philips prism 100 is used, the same effects as those of the embodiments and modifications can be obtained. [Explanation of symbols]
[0072] DESCRIPTION OF SYMBOLS 1, 1A, 1B, 1C, 1D, 1E, 1F...projection device, 2...image forming section, 3...projection optical system, 4...control section, 5...power supply section, 6...image processing section, 7...display driving section, 8...casing, 10...dichroic prism 10...dichroic prism, 11...first surface, 12...second surface, 13...third surface, 14...fourth surface, 16...first dichroic film, 17...second dichroic film, 18...first light absorbing layer, 19...second light absorbing layer, 21...first self-luminous display device, 22...second self-luminous display device, 23...third self-luminous display device, 24...substrate, 25...light emitting element, 25A...inner light emitting element, 25B...periphery light emitting element, 30...angle limiting filter tar, 31...glass plate, 32...lattice structure, 35...lens, 40...light absorbing member, 50...annular groove, 60...light absorbing member, 100...Philips prism, 100A...first prism, 100B...second prism, 100C...third prism, 101...first bonding surface, 102...second bonding surface, L...image light, L1...first combined light, LG...first image light, LB...second image light, LR...third image light, N...optical axis of light-emitting element, O...optical axis of image light, CA...camera, CH...switching mechanism, CL...ceiling, CM...seating part, GA...glasses, GL...glasses lens, M...viewer, MD...mobile device, S...screen, SC...screen, US...wearer, WA...wall.
Claims
1. The optical element has a first surface, a second surface, a third surface, and a fourth surface, and emits the synthesized image light from the fourth surface. a dichroic prism; a plurality of first light-emitting elements that emit light of a first wavelength, a first self-luminous display device that emits first image light onto a surface thereof; a plurality of second light-emitting elements that emit light of a second wavelength, a second self-luminous display device that emits second image light onto its surface; a plurality of third light-emitting elements that emit light of a third wavelength, a third self-luminous display device that emits third image light onto a surface thereof; a projection optical system that projects the image light from the dichroic prism onto a projection target; the first self-luminous display device, the second self-luminous display device, and the third self-luminous display device; a control unit for controlling the display device; The first self-luminous display device, the second self-luminous display device, and the third self-luminous display device a power supply unit that supplies power to the device and the control unit; and The first surface and the fourth surface are configured to reflect light along an optical axis of the image light emitted from the fourth surface. Axial facing, The annular outer peripheral surface of the dichroic prism surrounding the optical axis is a ring-shaped groove surrounding the optical axis at a position closest to the fourth surface.
2. Between the first self-luminous display device and the first surface, between the second self-luminous display device and the and between the third self-luminous display device and the second surface, and between the third self-luminous display device and the third surface. an angle limiting filter, the first self-luminous display device, the second self-luminous display device, and the third self-luminous display device; Each display device includes a plurality of light-emitting elements arranged in a matrix, The angle limiting filter narrows the light distribution angle of the image light emitted from each light emitting element.
2. The projection device according to claim 1, wherein:
3. a frame-shaped light absorbing member is provided on the outer periphery of the fourth surface; 3. The projection device according to claim 1 or 2.
4. 4. The optical fiber according to claim 1, wherein the annular groove is provided with a light absorbing member.
10. The projection device according to claim 9,
5. A device having a first surface, a second surface, a third surface, and a fourth surface, and emitting synthesized image light from the fourth surface. a dichroic prism; a plurality of first light-emitting elements that emit light of a first wavelength, a first self-luminous display device that emits first image light onto a surface thereof; a plurality of second light-emitting elements that emit light of a second wavelength, a second self-luminous display device that emits second image light onto its surface; a plurality of third light-emitting elements that emit light of a third wavelength, a third self-luminous display device that emits third image light onto a surface thereof; a projection optical system that projects the image light from the dichroic prism onto a projection target; the first self-luminous display device, the second self-luminous display device, and the third self-luminous display device; a control unit for controlling the display device; The first self-luminous display device, the second self-luminous display device, and the third self-luminous display device a power supply unit that supplies power to the device and the control unit; and The dichroic prism has a first dichroic film and a second dichroic film. death, The first dichroic film transmits the first image light and reflects the second image light. and synthesizing the first image light and the second image light by irradiating the first image light and the second image light. The second dichroic film transmits the first image light and reflects the third image light. and synthesizing the first image light and the third image light. The image light obtained by combining the first image light, the second image light, and the third image light is the light is emitted from the fourth surface of the chromatic prism, the fourth surface facing the projection optical system; The first dichroic film is provided with a peripheral light of the first image light and a peripheral light of the second image light. a frame-shaped first light absorbing layer that absorbs light is provided; The second dichroic film is provided with a peripheral light of the first image light and a peripheral light of the third image light. A projection device comprising a frame-shaped second light absorbing layer for absorbing light.
6. The first dichroic film and the second dichroic film intersect with each other.
6. The projection device according to claim 5, wherein:
7. 2. The method according to claim 1, wherein the dichroic prism is a Philips prism.
6. A projection device according to any one of claims 1 to 5.
8. A device having a first surface, a second surface, a third surface, and a fourth surface, and emitting synthesized image light from the fourth surface. a dichroic prism; a plurality of first light-emitting elements that emit light of a first wavelength, a first self-luminous display device that emits first image light onto a surface thereof; a plurality of second light-emitting elements that emit light of a second wavelength, a second self-luminous display device that emits second image light onto its surface; a plurality of third light-emitting elements that emit light of a third wavelength, a third self-luminous display device that emits third image light onto a surface thereof; a projection optical system that projects the image light from the dichroic prism onto a projection target; the first self-luminous display device, the second self-luminous display device, and the third self-luminous display device; a control unit for controlling the display device; The first self-luminous display device, the second self-luminous display device, and the third self-luminous display device a power supply unit that supplies power to the device and the control unit; and the first self-luminous display device, the second self-luminous display device, and the third self-luminous display device; Each of the display devices includes a plurality of light-emitting elements arranged in a matrix, Among the plurality of light emitting elements, the optical axes of the plurality of peripheral light emitting elements arranged in a frame shape on the outer periphery side are , a projection device characterized in that it is inclined toward the inner periphery.
9. A device having a first surface, a second surface, a third surface, and a fourth surface, and emitting synthesized image light from the fourth surface. a dichroic prism; a plurality of first light-emitting elements that emit light of a first wavelength, a first self-luminous display device that emits first image light onto a surface thereof; a plurality of second light-emitting elements that emit light of a second wavelength, a second self-luminous display device that emits second image light onto its surface; a plurality of third light-emitting elements that emit light of a third wavelength, a third self-luminous display device that emits third image light onto a surface thereof; a projection optical system that projects the image light from the dichroic prism onto a projection target; the first self-luminous display device, the second self-luminous display device, and the third self-luminous display device; a control unit for controlling the display device; The first self-luminous display device, the second self-luminous display device, and the third self-luminous display device a power supply unit that supplies power to the device and the control unit; and The control unit controls the first self-luminous display device, the second self-luminous display device, and the front controlling the light emission intensity of each light emitting element in each of the third self-luminous display devices; Among the plurality of light emitting elements, the light emission intensity of the plurality of peripheral light emitting elements arranged in a frame shape on the outer periphery side is The intensity is determined by the light emission intensity of the plurality of inner light emitting elements arranged inside the plurality of outer peripheral light emitting elements. A projection device characterized by its high brightness.
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