Polarized lighting system

Abstract

The utility model provides a polarization illumination system, which comprises an incidence mechanism, a polarization illumination mechanism, a polarization illumination mechanism and an illumination mechanism, the incidence mechanism comprises three light source assemblies, the three light source assemblies are respectively used for providing monochromatic light with three primary colors of red, green and blue, and the monochromatic light is non-polarized light; the polarization mechanism comprises three polarization assemblies, the polarization assemblies can carry out one-time polarization state conversion on at least one part of the non-polarized light to obtain first emergent light, and the polarization assemblies can carry out two-time polarization state conversion on at least the other part of the non-polarized light to obtain second emergent light; the polarization states of the first emergent light and the second emergent light are the same; the color combining mechanism is provided with a plurality of light filtering film layers, so that the emergent light of the three polarization assemblies is emitted on the same side of the color combining mechanism, and the emergent directions are the same; and the light uniformizing mechanism is used for improving the uniformity of the emergent light of the color combining mechanism. The polarization lighting system solves the problems of low light energy utilization rate and complex manufacturing process of the polarization lighting system in the prior art.

Description

Technical Field

[0001] The utility model relates to the technical field of projection display devices, and more particularly, to a polarization illumination system. Background Art

[0002] With the rapid development of projection display technology and the increasing demand of users for watching movies, liquid crystal display screens illuminated by external light sources have received more and more favor. However, usually for LCD (transmissive liquid crystal) and LCOS (reflective liquid crystal on silicon), a polarization device needs to be set in the optical system. If conventional devices such as linear polarizers are used, while allowing light of a certain polarization state to pass through, the light of the corresponding orthogonal polarization state is discarded, so the energy utilization rate of the system will be greatly reduced, and finally the brightness of the projected image will be relatively low. To further improve the energy utilization rate, a microlens array is often used to pre-converge the light beam to reduce the light-receiving area, so the alignment requirements between optical devices are strict and the manufacturing process is complex. In addition, since the divergence angle of the light exiting through the microlens array is relatively large, the efficiency of converting light from an unpolarized state to a linearly polarized state is reduced, which in turn affects the energy transmission of polarized light.

[0003] That is to say, the polarization illumination system in the prior art has problems of low light energy utilization rate and complex manufacturing process. Summary of the Utility Model

[0004] The main purpose of the utility model is to provide a polarization illumination system to solve the problems of low light energy utilization rate and complex manufacturing process in the polarization illumination system of the prior art.

[0005] To achieve the above purpose, the utility model provides a polarization illumination system. From the light-incident side to the light-exiting side of the polarization illumination system, the polarization illumination system sequentially includes: an incident mechanism, the incident mechanism includes three spaced-apart light source components, the three light source components are respectively used to provide monochromatic light of red, green, and blue primary colors, and the monochromatic light is unpolarized light; a polarization mechanism, the polarization mechanism includes three spaced-apart polarization components, the polarization components are arranged in one-to-one correspondence with the light source components, the polarization mechanism is used to convert the monochromatic light into linearly polarized light, the polarization component can convert at least a part of the unpolarized light through one polarization state conversion to obtain a first emitted light, the polarization component can convert at least another part of the unpolarized light through two polarization state conversions to obtain a second emitted light, and the polarization states of the first emitted light and the second emitted light are the same; a color combining mechanism, the three polarization components are arranged circumferentially around the color combining mechanism, the color combining mechanism has a plurality of filter film layers, so that the emitted lights of the three polarization components are emitted on the same side of the color combining mechanism and have the same emission direction; a light homogenizing mechanism, at least a part of the light homogenizing mechanism is coaxially arranged with the color combining mechanism, and the light homogenizing mechanism is used to improve the uniformity of the emitted light of the color combining mechanism.

[0006] Further, the color combining mechanism includes: four color combining right-angle prisms that are circumferentially glued together, with the right-angle faces of two adjacent color combining right-angle prisms completely coinciding, so that the inclined faces of the four color combining right-angle prisms face the polarization mechanism or the light homogenizing mechanism.

[0007] Further, the four color combining right-angle prisms are sequentially the first prism to the fourth prism, the first prism to the third prism are arranged in one-to-one correspondence with three polarization components, and the light-emitting surface of the color combining mechanism is located on the inclined face of the fourth prism.

[0008] Further, the fourth prism and the first prism are glued to form a first glued surface, the first prism and the second prism are glued to form a second glued surface, the second prism and the third prism are glued to form a third glued surface, and the third prism and the fourth prism are glued to form a fourth glued surface. The second glued surface and the fourth glued surface are used to reflect the light with the first monochromatic color and transmit the light with the second monochromatic color and the third monochromatic color, and the first glued surface and the third glued surface are used to reflect the light with the third monochromatic color and transmit the light with the first monochromatic color and the second monochromatic color.

[0009] Further, the polarization component includes: a polarization beam splitting part that is used to split monochromatic light into a first light ray and a second light ray with different polarization states. The first light ray passes through the polarization beam splitting part, and the second light ray is reflected by the polarization beam splitting part, so that the second light ray is emitted as the first emitted light; a conversion part, at least a part of the conversion part is used to change the propagation direction of the first light ray, and at least another part of the conversion part is used to change the polarization state of the first light ray, so that the first light ray is emitted as the second emitted light. The propagation direction and polarization state of the first emitted light and the second emitted light are the same.

[0010] Further, the polarization component includes a polarization right-angle prism and a rhombic prism that are glued together. The rhombic prism is glued to the inclined face of the polarization right-angle prism to set the polarization beam splitting part. The rhombic prism has a reflecting surface, and the reflecting surface is arranged opposite to the polarization beam splitting part to change the propagation direction of the first light ray. The polarization component further includes a 1 / 2 wave plate, and the 1 / 2 wave plate is glued to the light-emitting surface of the rhombic prism or the light-emitting surface of the polarization right-angle prism. The 1 / 2 wave plate is used to change the polarization state of the first light ray.

[0011] Further, the polarization component is arranged on the side adjacent to the light-emitting side of the color combining mechanism. The polarization right-angle prism is closer to the light source component than the rhombic prism. The second light ray is emitted from the other right-angle face of the polarization right-angle prism, and the 1 / 2 wave plate is arranged on the light-emitting surface of the rhombic prism.

[0012] Further, the polarization component is arranged on the side opposite to the light-emitting side of the color combining mechanism. The rhombic prism is closer to the light source component than the polarization right-angle prism. The second light ray is emitted from the face opposite to the light-incident surface of the rhombic prism, and the 1 / 2 wave plate is arranged on the light-emitting surface of the polarization right-angle prism.

[0013] Further, the light homogenizing mechanism includes a compound eye lens, and the length of the compound eye lens is greater than or equal to the width of the light emitted from the color combining mechanism.

[0014] Further, the light homogenizing mechanism further includes a first relay lens. The first relay lens is coaxially arranged with the compound eye lens, and at least one of the surface on the light incident side of the first relay lens and the surface on the light emitting side of the first relay lens is a convex surface.

[0015] Further, the light homogenizing mechanism further includes: a refractive component. The light incident side of the refractive component is coaxially arranged with the first relay lens, and the refractive component is used to change the propagation direction of the light emitted from the first relay lens; a second relay lens. The second relay lens is coaxially arranged with the light emitting side of the refractive component.

[0016] Further, the incident mechanism further includes a collimating component. The collimating component at least includes a first lens and a second lens, and at least one of the surface on the light incident side and the surface on the light emitting side of the first lens and the second lens is a convex surface.

[0017] Further, the polarization illumination system further includes a display chip. The display chip is coaxially arranged with the light emitting side of the light homogenizing mechanism, and the incident angle of the light emitted from the light homogenizing mechanism to the display chip is less than 20°.

[0018] Applying the technical solution of the present utility model, from the light incident side to the light emitting side of the polarization illumination system, the polarization illumination system includes an incident mechanism, a polarization mechanism, a color combining mechanism, and a light homogenizing mechanism. The incident mechanism includes three spaced light source components, and the three light source components are respectively used to provide monochromatic light of red, green, and blue primary colors, and the monochromatic light is non-polarized light; the polarization mechanism includes three spaced polarization components, and the polarization components are arranged in one-to-one correspondence with the light source components. The polarization mechanism is used to convert the monochromatic light into linearly polarized light. The polarization component can convert at least a part of the non-polarized light through one polarization state conversion to obtain a first emitted light, and the polarization component can convert at least another part of the non-polarized light through two polarization state conversions to obtain a second emitted light. The polarization states of the first emitted light and the second emitted light are the same; the three polarization components are arranged circumferentially around the color combining mechanism. The color combining mechanism has a plurality of filter film layers, so that the light emitted from the three polarization components is emitted on the same side of the color combining mechanism and in the same emission direction; at least a part of the light homogenizing mechanism is coaxially arranged with the color combining mechanism, and the light homogenizing mechanism is used to improve the uniformity of the light emitted from the color combining mechanism.

[0019] The present application provides a polarization illumination system. The incident mechanism can respectively provide monochromatic light of the three primary colors of red, green, and blue. The three polarization beam splitters respectively correspond to the monochromatic light from three light source components, and perform polarization conversion on each monochromatic light. When the light passes through the polarization beam splitter, it can undergo a polarization state conversion once, dividing the light into two lights with different polarization states. One of them is used as the first light to exit from the polarization mechanism, and then passes through the conversion unit to change the propagation direction and polarization state of the first light. The other is used as the second light to be reflected by the polarization beam splitter, so that the propagation directions and polarization states of the first light and the second light are the same. In this way, the two lights with different polarization states are converted into lights with the same polarization state for utilization, avoiding waste of light energy. At the same time, the conversion of the polarization state is realized by the polarization beam splitter, reducing the occupied volume of the polarization mechanism and avoiding complex processing and assembly processes of the polarization mechanism. In addition, the conversion of the polarization states of the three monochromatic lights by the three polarization beam splitters is the same, ensuring that all three monochromatic lights can participate in illumination and avoiding uneven illumination light colors caused by the lack of some monochromatic lights. The three polarization components are arranged circumferentially around the color combining mechanism. After the three monochromatic lights are respectively converted into lights with a single polarization state by the polarization mechanism, the three monochromatic lights are combined by the color combining mechanism, and then the illumination light is uniformly mixed and converged by the light homogenizing mechanism, ensuring that the illumination light has good uniformity and high brightness. Therefore, the polarization illumination system provided by the present application can convert the three monochromatic lights to the same polarization state while having a polarization efficiency close to 90%, high light energy utilization rate, and high uniformity and high intensity of the light after color combination. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings forming a part of this application are used to provide a further understanding of the present utility model. The schematic embodiments and descriptions thereof of the present utility model are used to explain the present utility model and do not constitute an improper limitation of the present utility model. In the drawings:

[0021] Figure 1 FIG. 9 shows a schematic structural diagram of the polarization illumination system according to Embodiment 1 of the present utility model;

[0022] Figure 2 FIG. 13 shows Figure 1 a three-dimensional structural diagram of the polarization illumination system in

[0023] Figure 3 FIG. 19 shows Figure 1 an overall optical path schematic diagram of the polarization illumination system in

[0024] Figure 4 FIG. 25 shows Figure 3 an enlarged schematic diagram of part A in

[0025] Figure 5 FIG. 31 shows Figure 1Illuminance distribution on the LCOS receiving surface of the polarization illumination system therein.

[0026] Among them, the above-mentioned drawings include the following reference numerals:

[0027] 10. Incident mechanism; 11. Light source assembly; 111. First incident assembly; 112. Second incident assembly; 113. Third incident assembly; 20. Polarization mechanism; 21. Polarization component; 211. Polarization beam splitting part; 212. Conversion part; 213. First component; 214. Second component; 215. Third component; 22. Polarization right-angle prism; 23. Rhombic prism; 24. 1 / 2 wave plate; 25. Reflective surface; 30. Color combining mechanism; 301. First bonding surface; 302. Second bonding surface; 303. Third bonding surface; 304. Fourth bonding surface; 31. Color combining right-angle prism; 311. First prism; 312. Second prism; 313. Third prism; 314. Fourth prism; 40. Light homogenizing mechanism; 41. Fly-eye lens; 42. First relay lens; 43. Refractive component; 44. Second relay lens; 50. Collimating component; 51. First lens; 52. Second lens; 60. Display chip. Specific embodiments

[0028] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the drawings and in combination with the embodiments.

[0029] It should be pointed out that unless otherwise specified, all technical and scientific terms used in the present application have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0030] In the present invention, unless otherwise stated, the orientation terms such as "upper, lower, top, bottom" are usually in the direction shown in the drawings, or in the vertical, perpendicular or gravitational direction of the component itself; similarly, for the convenience of understanding and description, "inner, outer" refer to the inner and outer of the contour of each component itself, but the above orientation terms do not limit the present invention.

[0031] It should be noted that in this specification, the expressions such as first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the feature. Therefore, without departing from the teachings of the present application, the first lens discussed below can also be referred to as the second lens or the third lens.

[0032] In the drawings, for ease of illustration, the thickness, size, and shape of the lens have been slightly exaggerated. Specifically, the spherical or aspherical shapes shown in the drawings are presented by way of example. That is, the spherical or aspherical shapes are not limited to those shown in the drawings. The drawings are for illustrative purposes only and are not drawn to an exact scale.

[0033] In this text, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not defined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closer to the object side is the object side surface of the lens, and the surface of each lens closer to the image side is called the image side surface of the lens. The judgment of the surface shape in the paraxial region can be based on the judgment method of those with ordinary knowledge in the field, and the concavity and convexity are judged by the positive and negative values of the R value (R refers to the radius of curvature in the paraxial region, usually the R value on the lens database (lens data) in optical software). For the object side surface, when the R value is positive, it is judged to be convex, and when the R value is negative, it is judged to be concave; for the image side surface, when the R value is positive, it is judged to be concave, and when the R value is negative, it is judged to be convex.

[0034] To solve the problems of low light energy utilization rate and complex manufacturing process in the existing polarization illumination system, the present utility model provides a polarization illumination system.

[0035] As Figures 1 to 5 shown, from the incident side to the exit side of the polarization illumination system, the polarization illumination system includes an incident mechanism 10, a polarization mechanism 20, a color combining mechanism 30, and a light homogenizing mechanism 40. The incident mechanism 10 includes three spaced-apart light source components 11, and the three light source components 11 are respectively used to provide monochromatic light of the three primary colors of red, green, and blue, and the monochromatic light is unpolarized light; the polarization mechanism 20 includes three spaced-apart polarization components 21, and the polarization components 21 are arranged in one-to-one correspondence with the light source components 11. The polarization mechanism 20 is used to convert the monochromatic light into linearly polarized light. The polarization component 21 can convert at least a part of the unpolarized light through one polarization state conversion to obtain a first output light, and the polarization component 21 can convert at least another part of the unpolarized light through two polarization state conversions to obtain a second output light. The polarization states of the first output light and the second output light are the same; the three polarization components 21 are arranged circumferentially around the color combining mechanism 30. The color combining mechanism 30 has a plurality of filter film layers, so that the output lights of the three polarization components 21 are output on the same side of the color combining mechanism 30 and have the same output direction; at least a part of the light homogenizing mechanism 40 is coaxially arranged with the color combining mechanism 30, and the light homogenizing mechanism 40 is used to improve the uniformity of the output light of the color combining mechanism 30.

[0036] The present application provides a polarization illumination system. The incident mechanism 10 can respectively provide monochromatic light of red, green, and blue primary colors. The three polarization components 21 respectively correspond to the monochromatic light from the three light source components 11, and perform polarization conversion on each monochromatic light. When the light passes through the polarization component 21, it is divided into two groups and undergoes one polarization state conversion and two polarization state conversions respectively, and finally the emitted light with the same propagation direction and polarization state is obtained. In this way, the light of two different polarization states is converted into light with the same polarization state for utilization, avoiding waste of light energy. At the same time, the conversion of the polarization state is realized by the polarization component 21, reducing the occupied volume of the polarization mechanism 20 and avoiding the complexity of the processing and assembly processes of the polarization mechanism 20. In addition, the conversion of the polarization states of the three monochromatic lights by the three polarization components 21 is the same, ensuring that all three monochromatic lights can participate in illumination and avoiding uneven illumination light color caused by the lack of some monochromatic lights. The three polarization components 21 are arranged circumferentially around the color mixing mechanism 30, which is beneficial to improving the space utilization rate and reducing the occupied space of the polarization illumination system. After the three monochromatic lights are respectively converted into light with a single polarization state by the polarization mechanism 20, they are then combined by the color mixing mechanism 30, and then pass through the light homogenizing mechanism 40 to uniformly mix and converge the illumination light, ensuring that the illumination light has good uniformity and high brightness. Therefore, the polarization illumination system provided by the present application, while converting the three monochromatic lights to the same polarization state, has a polarization efficiency close to 90%, high light energy utilization rate, and high uniformity and high intensity of the light after color mixing.

[0037] As Figures 1 to 3 shown, the polarization component 21 includes a polarization beam splitting part 211 and a conversion part 212. The polarization beam splitting part 211 is used to divide the monochromatic light into a first light ray and a second light ray with different polarization states. The first light ray passes through the polarization beam splitting part 211, and the second light ray is reflected by the polarization beam splitting part 211; at least a part of the conversion part 212 is used to change the propagation direction of the first light ray, and at least another part of the conversion part 212 is used to change the polarization state of the first light ray, so that the propagation direction and polarization state of the first light ray and the second light ray are the same. That is to say, the monochromatic unpolarized light is divided by the polarization beam splitting part 211 into a first light ray (P light) and a second light ray (S light) with different polarization states and perpendicular propagation directions. The first light ray passes through the polarization beam splitting part 211 and continues to propagate along the optical path. The conversion part 212 changes the propagation direction and polarization state of the first light ray (P light is converted to S light). The polarization state of the second light ray is the polarization state of the final illumination light (S light). Therefore, the second light ray only changes its propagation direction when passing through the polarization component 21. At this time, the first light ray and the second light ray have the same propagation direction and polarization state after exiting the polarization component 21. In this way, the polarization efficiency is close to 90%, greatly improving the light energy utilization rate. The polarization component 21 realizes the purpose of changing the propagation direction and polarization state of the unpolarized monochromatic light to a unified combined polarized light, providing high-quality polarized light for beam combination. As Figures 1 to 3As shown in the figure, the polarization component 21 includes a polarization right-angle prism 22 and a rhombic prism 23 which are adhesively disposed. The rhombic prism 23 is adhesively joined to the inclined surface of the polarization right-angle prism 22 to form a polarization beam splitting part 211. The rhombic prism 23 has a reflecting surface 25 which is disposed opposite to the polarization beam splitting part 211 to change the propagation direction of the first light ray. The polarization component 21 further includes a half-wave plate 24 which is adhesively disposed on the light-emitting surface of the rhombic prism 23 or the light-emitting surface of the polarization right-angle prism 22. The half-wave plate 24 is used to change the polarization state of the first light ray. The polarization beam splitting part 211 is disposed at the adhesive joint of the inclined surface of the rhombic prism 23 and the polarization right-angle prism 22. Only the first light ray or the second light ray passes through the rhombic prism 23 and the polarization right-angle prism 22 respectively. The half-wave plate 24 is disposed on the light-emitting surface of the rhombic prism 23 or the light-emitting surface of the polarization right-angle prism 22 to change the polarization state of the first light ray to be the same as that of the second light ray. Combining the polarization beam splitting part 211 and the orientation of the inclined surface where the reflecting surface 25 is located, the first light ray and the second light ray are transmitted towards the color combining mechanism 30, reducing the waste of light energy.

[0038] It should be noted that since the three polarization components 21 are arranged around the color combining mechanism 30, the different structures of the polarization components 21 at different positions will be described below.

[0039] As Figures 1 to 3 shown, among the three polarization components 21, two polarization components 21 are disposed on the side adjacent to the light-emitting side of the color combining mechanism 30. At this time, the polarization right-angle prism 22 is closer to the light source component 11 than the rhombic prism 23. The second light ray exits from the other right-angle surface of the polarization right-angle prism 22. The half-wave plate 24 is disposed on the light-emitting surface of the rhombic prism 23. That is to say, along the propagation direction of the optical path, the polarization component 21 is sequentially composed of a polarization right-angle prism 22, a rhombic prism 23, and a half-wave plate 24. Among them, the monochromatic light first enters the right-angle surface of the polarization right-angle prism 22, and is split into a first light ray and a second light ray with different polarization states at the adhesive joint surface of the polarization right-angle prism 22 and the rhombic prism 23. The first light ray enters the rhombic prism 23 and continues to propagate along the optical path. After being reflected by the reflecting surface 25, it exits after changing the polarization state through the half-wave plate 24. The second light ray is reflected by the adhesive joint surface of the polarization right-angle prism 22 and the rhombic prism 23 and exits from the other right-angle surface of the polarization right-angle prism 22. At this time, the propagation directions and polarization states of the two emitted light rays are the same.

[0040] As Figures 1 to 3As shown in the figure, among the three polarization components 21, one polarization component 21 is arranged on the side opposite to the light-emitting side of the color-combining mechanism 30. The rhombic prism 23 is closer to the light source component 11 than the polarization right-angle prism 22. The second light ray exits from the surface opposite to the light-incident surface of the rhombic prism 23. The 1 / 2 wave plate 24 is arranged on the light-emitting surface of the polarization right-angle prism 22. That is to say, in this polarization component 21, along the light path propagation direction, the polarization component 21 is successively composed of a rhombic prism 23, a polarization right-angle prism 22, and a 1 / 2 wave plate 24. Monochromatic light first enters through one surface of the rhombic prism 23 and is split into a first light ray and a second light ray with different polarization states at the glued surface between the rhombic prism 23 and the polarization right-angle prism 22. The first light ray enters the polarization right-angle prism 22 and continues to propagate along the light path. After reaching a right-angle surface of the polarization right-angle prism 22, it exits after changing the polarization state through the 1 / 2 wave plate 24. The second light ray is reflected by the reflecting surface 25 and exits from the surface of the rhombic prism 23 opposite to the light-incident surface. At this time, the propagation directions and polarization states of the two outgoing light rays are the same. As Figures 1 to 3 As shown in the figure, the color-combining mechanism 30 includes four color-combining right-angle prisms 31 that are circumferentially glued and connected. The right-angle surfaces of two adjacent color-combining right-angle prisms 31 completely coincide, so that the inclined surfaces of the four color-combining right-angle prisms 31 face the polarization mechanism 20 or the light homogenizing mechanism 40. By strictly assembling and gluing the right-angle surfaces of the four color-combining right-angle prisms 31, the color-combining mechanism 30 presents a square. Among them, the right-angle surfaces of the adjacent color-combining right-angle prisms 31 completely coincide. Three groups of polarized light with the same polarization state are perpendicularly incident from the three inclined surfaces of the color-combining right-angle prisms 31 of the color-combining mechanism 30, and the outgoing light has completed the beam combination of the three groups of polarized light. The color-combining mechanism 30 realizes the color combination of the light beam with a small volume, forms a structural assembly in a simple way, and greatly improves the space efficiency of the polarization illumination system.

[0041] As Figures 1 to 3 As shown in the figure, the four color-combining right-angle prisms 31 are successively the first prism 311 to the fourth prism 314. The first prism 311 to the third prism 313 are arranged in one-to-one correspondence with the three polarization components 21. The light-emitting surface of the color-combining mechanism 30 is located on the inclined surface of the fourth prism 314. The four color-combining right-angle prisms 31 are successively and circumferentially composed of the first prism 311, the second prism 312, the third prism 313, and the fourth prism 314. Among them, the inclined surface of the first prism 311 corresponds to the first component 213, the inclined surface of the second prism 312 corresponds to the second component 214, the inclined surface of the third prism 313 corresponds to the third component 215, and the inclined surface of the fourth prism 314 corresponds to the light-emitting surface of the color-combining mechanism 30. By setting the three color-combining right-angle prisms 31 in one-to-one correspondence with the three polarization components 21, the polarized light in three directions is combined and parallelly exits through the inclined surface of the fourth prism 314.

[0042] As Figures 1 to 3As shown, the fourth prism 314 and the first prism 311 are glued together to form the first glued surface 301, the first prism 311 and the second prism 312 are glued together to form the second glued surface 302, the second prism 312 and the third prism 313 are glued together to form the third glued surface 303, and the third prism 313 and the fourth prism 314 are glued together to form the fourth glued surface 304. The second glued surface 302 and the fourth glued surface 304 are used to reflect light with the first monochromatic color and transmit light with the second and third monochromatic colors, while the first glued surface 301 and the third glued surface 303 are used to reflect light with the third monochromatic color and transmit light with the first and second monochromatic colors. The color combining mechanism 30 is composed of four color combining right-angled prisms 31, and the four color combining right-angled prisms 31 are combined to form four mutually perpendicular glued surfaces. Among them, the first glued surface 301 is formed by gluing the right-angled surface of the fourth prism 314 and the right-angled surface of the first prism 311, the second glued surface 302 is formed by gluing the right-angled surface of the first prism 311 and the right-angled surface of the second prism 312, the third glued surface 303 is formed by gluing the right-angled surface of the second prism 312 and the right-angled surface of the third prism 313, and the fourth glued surface 304 is formed by gluing the right-angled surface of the third prism 313 and the right-angled surface of the fourth prism 314. At the same time, the first glued surface 301 and the third glued surface 303 transmit the first and second monochromatic lights and reflect the third monochromatic light, while the second glued surface 302 and the fourth glued surface 304 transmit the second and third monochromatic lights and reflect the first monochromatic light. The color combining mechanism 30 makes the propagation directions of the lights of the three monochromatic colors the same by restricting the transmission or reflection of light of a specific monochromatic color through the four glued surfaces, and efficiently completes the beam combination of the three monochromatic polarized lights.

[0043] As Figures 1 to 3 shown, the light homogenizing mechanism 40 includes a fly-eye lens 41, and the length of the fly-eye lens 41 is greater than or equal to the width of the outgoing light of the color combining mechanism 30. The fly-eye lens 41 is a double-sided microlens array structure, and the centers of the corresponding sub-eye curved surfaces on both sides are aligned, so as to subdivide and diffusely shape the outgoing light beam of the color combining mechanism 30 to achieve color mixing and light homogenization; its sub-eye curved surface is a spherical surface, aspherical surface or free-form surface with the same or similar geometric parameters, and its focal length is close to the distance between the two microstructured surfaces, which can reduce the optical path crosstalk when light is incident at a large angle. The length of the fly-eye lens 41 is greater than or equal to the width of the outgoing light of the color combining mechanism 30, which can ensure that the fly-eye lens 41 receives all the outgoing light of the color combining mechanism 30 to ensure the light energy utilization rate.

[0044] As Figures 1 to 4As shown, the light homogenizing mechanism 40 further includes a first relay lens 42. The first relay lens 42 is coaxially arranged with the compound eye lens 41. At least one of the surface on the light incident side and the surface on the light exiting side of the first relay lens 42 is a convex surface. After the three monochromatic polarized light beams are combined, they sequentially pass through the compound eye lens 41 and the first relay lens 42. The compound eye lens 41 and the first relay lens 42 play a role in homogenizing light on the same axis. Such an arrangement can converge the fine sub-light beams emitted by the compound eye lens 41 and overlap and homogenize them in space to obtain more uniform light to illuminate the display chip 60.

[0045] As Figures 1 to 3 shown, the light homogenizing mechanism 40 further includes: a refractive component 43. The light incident side of the refractive component 43 is coaxially arranged with the first relay lens 42. The refractive component 43 is used to change the propagation direction of the light emitted by the first relay lens 42; a second relay lens 44. The second relay lens 44 is coaxially arranged with the light exiting side of the refractive component 43. The refractive component 43 is used to change the propagation direction of the light emitted by the first relay lens 42; the second relay lens 44 is coaxially arranged with the light exiting side of the refractive component 43. By arranging the refractive component 43 to change the light propagation direction and further converging the light by the second relay lens 44, it is beneficial to achieve good illumination uniformity on the display chip 60.

[0046] Optionally, the refractive component 43 includes a turning mirror. The turning mirror can be a PBS prism, which is composed of two right-angle prisms glued together. A polarization beam splitting film layer is plated on the glued inclined surface or a polarization beam splitting film piece is attached. It can also be a right-angle prism or a plane mirror. A reflective film layer is plated on the inclined surface or a reflective film piece is attached to reflect the S-polarized light to realize the turning of the illumination light path.

[0047] As Figures 1 to 4 shown, the incident mechanism 10 further includes a collimating component 50. The collimating component 50 at least includes a first lens 51 and a second lens 52. At least one of the surface on the light incident side and the surface on the light exiting side of the first lens 51 and the second lens 52 is a convex surface. The collimating component 50 sequentially includes the first lens 51 and the second lens 52 along the light path. At least one of the surface on the light incident side and the surface on the light exiting side of the first lens 51 and the second lens 52 is a convex surface, which is beneficial to converge the light, reduce the light energy loss, and finally achieve the function of converging and collimating the three monochromatic lights and the three polarized monochromatic lights, and incident on the polarization mechanism 20 at a smaller incident angle. The efficiency of converting non-polarized light into linearly polarized light by the polarization mechanism 20 will be higher, which is beneficial to the energy transmission of the polarized light, and then improves the light energy utilization rate. As Figures 1 to 5As shown, the polarization illumination system further includes a display chip 60. The display chip 60 is coaxially arranged with the light-emitting side of the light homogenizing mechanism 40, and the incident angle of the light emitted from the light homogenizing mechanism 40 onto the display chip is less than 20°. The optical path starts from the incident mechanism 10, passes through the polarization mechanism 20, the color combining mechanism 30, and the light homogenizing mechanism 40, and then projects onto the display chip 60 at an incident angle less than 20°, forming a uniformly shaped display with a certain ratio.

[0048] Optionally, the display chip 60 can be one of LCD or LCOS. By controlling the applied voltage, the twisting angle of the liquid crystal molecules is changed for image display.

[0049] Embodiment 1

[0050] As Figures 1 to 5 As shown, the polarization illumination system of this embodiment includes an incident mechanism 10, a polarization mechanism 20, a color combining mechanism 30, a light homogenizing mechanism 40, and a display chip 60. Along the direction from the first prism 311 to the third prism 313, the three light source components 11 respectively include three monochromatic LED light sources with a Lambertian light intensity distribution, providing red, green, and blue primary color light beams respectively. Among them, the main wavelength of the red light LED is 610 - 622 nm, the main wavelength of the green light LED is 518 - 536 nm, and the main wavelength of the blue light LED is 455 - 465 nm. The three monochromatic lights are all non-polarized lights.

[0051] As Figures 1 to 4 As shown, the color combining mechanism 30 includes four color combining right-angle prisms 31 that are circumferentially glued together. The right-angle surfaces of two adjacent color combining right-angle prisms 31 completely coincide, so that the inclined surfaces of the four color combining right-angle prisms 31 face the polarization mechanism 20 or the light homogenizing mechanism 40. Specifically, a filter film layer that transmits red and green lights and reflects blue light is plated on the first gluing surface 301 and the third gluing surface 303, while a filter film layer that transmits blue and green lights and reflects red light is plated on the second gluing surface 302 and the fourth gluing surface 304. The red light emitted from the first incident component 111 enters the first prism 311. Part of the light is reflected by the second gluing surface 302 and directly reaches the fourth prism 314, and the remaining light reaches the fourth prism 314 after passing through the first gluing surface 301, and then is reflected by the fourth gluing surface 304 towards the direction of the fly-eye lens 41. The green light emitted from the second incident component 112 successively enters the second prism 312 to the fourth prism 314 and directly exits towards the direction of the fly-eye lens 41. The blue light emitted from the third incident component 113 successively enters the third prism 313. Part of the light is reflected by the third gluing surface 303 and directly reaches the fourth prism, and the remaining light reaches the fourth prism 314 after passing through the fourth gluing surface 304, and then is reflected by the first gluing surface 301 towards the direction of the fly-eye lens 41. Finally, the red, green, and blue lights are parallelly aggregated on the same optical path, realizing the beam combination of the three monochromatic lights.

[0052] As Figures 1 to 4As shown in the figure, the refractive component 43 is composed of two reflecting right-angle prisms. The polarized light after color combination by the color combination mechanism 30 sequentially passes through the fly-eye lens 41 and the first relay lens 42, converges the optical path to a coaxial reflecting right-angle prism, and after the optical path is reflected, it passes through the second relay lens 44, thereby realizing the turning of the optical path. As Figures 1 to 4 As shown in the figure, micro-lens array units are correspondingly arranged on both sides of the fly-eye lens 41 to realize the color mixing and light homogenization functions similar to a Köhler illumination system. The nearly collimated wide beam emitted by the color combination mechanism 30 is focused by the micro-lens units on the incident light surface of the fly-eye lens 41, and can be subdivided into multiple sub-beams arranged in an array, which is equivalent to the entire light source being subdivided into multiple sub-light sources imaged near the light-emitting surface.

[0053] Specifically, to meet the color mixing and light homogenization conditions similar to a Köhler illumination system, the curved surfaces of all micro-lens units of the fly-eye lens 41 are spherical surfaces, aspherical surfaces or free-form surfaces with the same or similar geometric parameters, and usually the focal length is taken between 0.4 and 0.7 mm. This focal length is close to the spacing distance between the two micro-structured surfaces on both sides, that is, the thickness of the fly-eye lens 41, which can reduce the optical path crosstalk when light is incident at a large angle.

[0054] Specifically, based on the effective area range of the display chip 60 and appropriate light energy utilization rate, the irradiation spot is generally rectangular or square, and its aspect ratio should be consistent with that of the display chip. For example, the aspect ratio of a DMD chip is usually 4:3 or 16:9.

[0055] Optionally, to achieve a square spot, the micro-lens units opposite to each other on the light-emitting surface and the incident light surface of the fly-eye lens 41 are arranged in a square array, so that the small light-transmitting apertures corresponding to each unit are square. The size of the spot is proportional to the aperture of the micro-lens unit. By adjusting the row and column spacing of the micro-lens array, the aperture of the micro-lens unit can be controlled, and then irradiation spots of different sizes can be obtained to meet the purpose of uniformly illuminating the display chip 60. Specifically, for example, the row and column spacing are both taken as 0.17 mm. Similarly, if a rectangular spot is to be achieved, it can be analogized.

[0056] Optionally, the optical surfaces of the first lens 51, the second lens 52, the first relay lens 4, and the second relay lens 44 in the collimation component 50 can be spherical surfaces, aspherical surfaces or free-form surfaces to control the light path. Specifically, an anti-reflection film can be deposited on the lens surface to improve the transmission efficiency. By designing and optimizing the surface shapes of each lens, good illumination uniformity can be achieved on the display chip 60.

[0057] Optionally, for the production of optical lenses, transparent plastics such as PC and PMMA can be used for injection molding, or flint glass or crown glass materials can be selected, and processed by one or several processes such as glass molding and cold processing.

[0058] Optionally, according to the constraints of the appearance volume of the projection optical machine and the clear aperture of the downstream imaging system, reasonably control the structural dimensions of each component of the illumination system to ensure that the optical machine has a relatively small structural volume. For a compact projection optical machine with a small volume, the outer diameter of the lens of the illumination system components is usually limited to 3-8 mm.

[0059] As Figures 1 to 5 shown, reasonably design and configure each optical component in the polarization illumination system. The light emitted by the red, green, and blue monochromatic light sources is polarized by the polarization mechanism 20, combined by the color combination mechanism 30, shaped by the fly-eye lens 41, turned by the refractive component 43, converged by the first relay lens 42 and the second relay lens 44, and then incident on the LCOS at an appropriate beam angle that can effectively pass through the subsequent imaging system. For example, in a certain embodiment, it should be less than 20°. A relatively uniform square light spot is presented within the receiving window on the LCOS surface, and the illumination uniformity can reach more than 85%, and the color is uniform. The receiving efficiency of the LCOS effective window for the light source energy is about 32.8%, which is higher than that of similar products in the industry and has performance advantages.

[0060] In this embodiment, the unpolarized light beams emitted by the discrete red, green, and blue monochromatic light sources are converted into S-line polarized light after corresponding polarization splitting, and enter the color combination mechanism 30 for red, green, and blue combination from three mutually parallel optical axis directions, and then the incident light beam is subdivided and shaped through the microstructure surface of the fly-eye lens 41. The sub-beams are emitted from the microlens units oppositely arranged on the light-emitting surface of the fly-eye lens 41, converged by the curved surfaces of the subsequent first relay lens 42 and the second relay lens 44, and the light path is turned by a turning mirror such as a polarization beam splitter prism, a reflecting right-angle prism, a reflecting plane mirror, etc. The sub-light spots generated are superimposed on each other in space. Based on the array symmetry of the sub-beams, the energy and color non-uniformities of the sub-beams cancel each other out, and finally a relatively uniform target light spot is formed on the surface of the display chip 60.

[0061] Obviously, the above-described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0062] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0063] It should be noted that the terms "first", "second", etc. in the description, claims and above-mentioned drawings of this application are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments of this application described here can be implemented in an order other than those illustrated or described here.

[0064] The above are only the preferred embodiments of the present utility model and are not used to limit the present utility model. For those skilled in the art, various changes and modifications can be made to the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A polarization illumination system, characterized in that, From the incident light side to the emergent light side of the polarization illumination system, the polarization illumination system sequentially includes: An incident mechanism (10), the incident mechanism (10) includes three light source components (11) arranged at intervals, the three light source components (11) are respectively used to provide monochromatic light of red, green, and blue primary colors, and the monochromatic light is unpolarized light; A polarization mechanism (20), the polarization mechanism (20) includes three polarization components (21) arranged at intervals, the polarization components (21) are arranged in one-to-one correspondence with the light source components (11), the polarization mechanism (20) is used to convert the monochromatic light into linearly polarized light, the polarization component (21) can convert at least a part of the unpolarized light through a polarization state conversion once to obtain a first emergent light, the polarization component (21) can convert at least another part of the unpolarized light through two polarization state conversions to obtain a second emergent light, and the polarization states of the first emergent light and the second emergent light are the same; A color combining mechanism (30), the three polarization components (21) are arranged circumferentially around the color combining mechanism (30), the color combining mechanism (30) has a plurality of filter film layers, so that the emergent lights of the three polarization components (21) emerge on the same side of the color combining mechanism (30) and have the same emergent direction; A light homogenizing mechanism (40), at least a part of the light homogenizing mechanism (40) is coaxially arranged with the color combining mechanism (30), and the light homogenizing mechanism (40) is used to improve the uniformity of the emergent light of the color combining mechanism (30).

2. The polarization illumination system according to claim 1, wherein The color combining mechanism (30) includes: four color combining right-angle prisms (31) that are circumferentially glued and connected, and the right-angle surfaces of two adjacent color combining right-angle prisms (31) completely coincide, so that the inclined surfaces of the four color combining right-angle prisms (31) face the polarization mechanism (20) or the light homogenizing mechanism (40).

3. The polarization illumination system according to claim 2, characterized in that, The four color combining right-angle prisms (31) are sequentially the first prism (311) to the fourth prism (314), the first prism (311) to the third prism (313) are arranged in one-to-one correspondence with the three polarization components (21), and the emergent light surface of the color combining mechanism (30) is located on the inclined surface of the fourth prism (314).

4. The polarization illumination system according to claim 3, wherein The fourth prism (314) and the first prism (311) are glued to form a first glued surface (301), the first prism (311) and the second prism (312) are glued to form a second glued surface (302), the second prism (312) and the third prism (313) are glued to form a third glued surface (303), the third prism (313) and the fourth prism (314) are glued to form a fourth glued surface (304), the second glued surface (302) and the fourth glued surface (304) are used to reflect light with a first monochromatic color and transmit light with a second monochromatic color and a third monochromatic color, and the first glued surface (301) and the third glued surface (303) are used to reflect light with a third monochromatic color and transmit light with a first monochromatic color and a second monochromatic color.

5. The polarization illumination system according to claim 1, characterized in that The polarization component (21) includes: A polarization beam splitting unit (211) that is configured to split the monochromatic light into a first light ray and a second light ray with different polarization states, where the first light ray passes through the polarization beam splitting unit (211) and the second light ray is reflected by the polarization beam splitting unit (211) so that the second light ray is emitted as the first output light; A conversion unit (212), at least a part of the conversion unit (212) is configured to change the propagation direction of the first light ray, and at least another part of the conversion unit (212) is configured to change the polarization state of the first light ray so that the first light ray is emitted as the second output light, and the propagation directions and polarization states of the first output light and the second output light are the same.

6. The polarization illumination system according to claim 5, wherein The polarization assembly (21) includes a polarization right-angle prism (22) and a rhombic prism (23) that are adhesively disposed. The rhombic prism (23) is adhesively disposed to the inclined surface of the polarization right-angle prism (22) to provide the polarization beam splitting unit (211). The rhombic prism (23) has a reflection surface (25), and the reflection surface (25) is disposed opposite to the polarization beam splitting unit (211) to change the propagation direction of the first light ray. The polarization assembly (21) further includes a 1 / 2 wave plate (24), and the 1 / 2 wave plate (24) is adhesively disposed to the light-emitting surface of the rhombic prism (23) or the light-emitting surface of the polarization right-angle prism (22), and the 1 / 2 wave plate (24) is configured to change the polarization state of the first light ray.

7. The polarization illumination system according to claim 6, wherein The polarization assembly (21) is disposed on a side adjacent to the light-emitting side of the color combining mechanism (30). The polarization right-angle prism (22) is closer to the light source assembly (11) than the rhombic prism (23). The second light ray is emitted from another right-angle surface of the polarization right-angle prism (22), and the 1 / 2 wave plate (24) is disposed on the light-emitting surface of the rhombic prism (23).

8. The polarization illumination system according to claim 7, wherein The polarization assembly (21) is disposed on a side opposite to the light-emitting side of the color combining mechanism (30). The rhombic prism (23) is closer to the light source assembly (11) than the polarization right-angle prism (22). The second light ray is emitted from a surface opposite to the light-incident surface of the rhombic prism (23), and the 1 / 2 wave plate (24) is disposed on the light-emitting surface of the polarization right-angle prism (22).

9. The polarization illumination system according to any one of claims 1 to 7, characterized in that The light homogenizing mechanism (40) includes a fly-eye lens (41), and the length of the fly-eye lens (41) is greater than or equal to the width of the output light of the color combining mechanism (30).

10. The polarization illumination system according to claim 9, wherein, The light homogenizing mechanism (40) further includes a first relay lens (42), the first relay lens (42) is coaxially disposed with the fly-eye lens (41), and at least one of the surface on the light-incident side of the first relay lens (42) and the surface on the light-emitting side of the first relay lens (42) is a convex surface.

11. The polarization illumination system according to claim 10, wherein The light homogenizing mechanism (40) further includes: A refractive component (43), the light-incident side of the refractive component (43) is coaxially disposed with the first relay lens (42), and the refractive component (43) is configured to change the propagation direction of the light emitted from the first relay lens (42); A second relay lens (44), the second relay lens (44) being coaxially arranged with the light-emitting side of the refractive component (43).

12. The polarization illumination system according to any one of claims 1 to 7, characterized in that, The incident mechanism (10) further includes a collimating component (50), the collimating component (50) at least including a first lens (51) and a second lens (52), at least one of the surfaces on the light-incident side and the light-emitting side of the first lens (51) and the second lens (52) being a convex surface.

13. The polarization illumination system according to any one of claims 1 to 7, characterized in that, The polarization illumination system further includes a display chip (60), the display chip (60) being coaxially arranged with the light-emitting side of the light homogenizing mechanism (40), and the incident angle of the light emitted by the light homogenizing mechanism (40) incident on the display chip (60) being less than 20°.

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