CN216351723U

CN216351723U - Single micro-transmission projection system

Info

Publication number: CN216351723U
Application number: CN202122199610.7U
Authority: CN
Inventors: 胡飞; 方元戎; 严子深; 李屹
Original assignee: Appotronics Corp Ltd
Current assignee: Shenzhen Appotronics Corp Ltd
Priority date: 2021-09-10
Filing date: 2021-09-10
Publication date: 2022-04-19
Anticipated expiration: 2031-09-10

Abstract

The application discloses single little projection system that passes through, this single little projection system that passes through includes: the light source device is used for generating red light, green light and blue light; the single micro-transparent panel receives red light, green light and blue light, and the emergent primary light of the red light and the primary light of the green light are intersected with the primary light of the blue light; the first dispersion light-splitting device is used for guiding the principal ray of red light, the principal ray of green light and the principal ray of blue light; and the projection lens receives the red light, the green light and the blue light after being guided and corrected so as to form an image on a screen. According to the single micro-transmission projection system, the first dispersion light splitting device is arranged behind the single micro-transmission panel, and the main light of red light, the main light of green light and the main light of blue light are guided, so that the divergence angle of the red light, the green light and the blue light is reduced, and the expansion of the single micro-transmission projection system is maintained.

Description

Single micro-transmission projection system

Technical Field

The application relates to the technical field of projection, in particular to a single micro-transmission projection system.

Background

The projection system includes various projection modes, specifically including a DMD (Digital micro-mirror Device), an LCoS (liquid Crystal on silicon), and an LCD, and since the response time of the DMD is only 15 μ s, the response time of the LCoS is about 1.5ms, and the response time of the LCD is usually > 7ms, the single DMD projection and the single LCoS projection are mainly used at present, and the single panel projection using the LCD as a light valve is usually not considered. However, single DMD projection and single LCoS projection are still complex in optical path due to the characteristics of their reflective optical paths, and it is difficult to further reduce the volume.

When the LCD panel is used for projection display, the LCD panel only uses one microlens array, one microlens unit of the microlens array covers three sub-pixels on the LCD panel, wherein the three sub-pixels are respectively a red pixel, a blue pixel and a green pixel, red light, blue light and green light emitted by the three sub-pixels have large divergence angles, and included angles exist among principal rays of the red light, principal rays of the blue light and principal rays of the green light, so that the light field angle of an incident lens is too large, and the lens cost is too high.

SUMMERY OF THE UTILITY MODEL

The application provides a single micro-perspective projection system, which comprises:

the light source device is used for generating a first light beam, and the first light beam at least comprises red light, green light and blue light;

the single micro-transparent panel receives red light, green light and blue light, and the emergent primary light of the red light and the primary light of the green light are intersected with the primary light of the blue light;

the first dispersion light-splitting device is used for guiding the principal ray of red light, the principal ray of green light and the principal ray of blue light;

and the projection lens receives the red light, the green light and the blue light after being guided and corrected so as to form an image on a screen.

Optionally, the first dispersion optical splitter includes a first sub-device and a second sub-device, the first sub-device is made of a first material, the second sub-device is made of a second material, the refractive indexes of the first material and the second material for green light are the same, the refractive indexes of the first material and the second material for red light are different, and the refractive indexes of the first material and the second material for blue light are different, so that the red light and the blue light are deflected by the first dispersion optical splitter.

Optionally, the first sub-device includes one side forming a first wedge-shaped structure and the other side forming a first plane, the second sub-device includes one side forming a second wedge-shaped structure and the other side forming a second plane, the first wedge-shaped structure and the second wedge-shaped structure are arranged in an embedded manner, the first plane is arranged in parallel with the second plane, and the red light, the green light and the blue light sequentially pass through the second plane, the second wedge-shaped structure, the first wedge-shaped structure and the first plane.

Optionally, the red light and the blue light are deflected to generate a deflection angle, and the first sub-device comprises a pitch angle, a tilt angle and a base angle;

the sum of the pitch angle, the inclination angle and the base angle is 180 degrees, the base angle is less than or equal to 90 degrees, the base angle is in negative correlation with the deflection angle, the inclination angle is in positive correlation with the deflection angle, and the pitch angle is in negative correlation with the deflection angle.

Optionally, the single micro-transmissive projection system comprises at least two first dispersing optical devices, which are stacked.

Optionally, the single micro-transmissive panel is an LTPS-LCD.

Optionally, the single micro-transparent panel includes a micro-lens array and an LCD panel, and the micro-lens array is disposed on the LCD panel and covers the red, green, and blue pixels of the LCD panel, so that the red light, the green light, and the blue light converge on the red pixel, the green pixel, and the blue pixel, respectively.

Optionally, the red pixel, the green pixel and the blue pixel constitute a color pixel, and the first dispersion light-splitting device is disposed at an intersection position of principal rays of red light and principal rays of blue light emitted by two adjacent color pixels.

Optionally, the projection lens satisfies the following relation:

θ_{lens barrel}＝sin^-1[n*sin(tan^-1(3x/L))]

Wherein, theta_{Lens barrel}The half angle of incident light of the projection lens is the lens entering half angle, x is the pixel size of a red pixel, a green pixel or a blue pixel, L is the distance from the micro-lens array to the red pixel, the green pixel or the blue pixel, and n is the glass refractive index of the projection lens.

Optionally, the light source device comprises:

a light emitting source for generating white light;

the light collection system collects the white light so as to enable the white light to be emitted in parallel;

and the second dispersion light-splitting device receives the white light to split the white light into red light, green light and blue light.

Optionally, the second dispersive optical device and the first dispersive optical device have the same structure, and the second dispersive optical device and the first dispersive optical device are symmetrically arranged relative to the single micro-transparent panel.

Optionally, the light collection system comprises:

the light homogenizing device receives the white light and performs light homogenizing treatment on the white light;

and the lens assembly receives the white light after the dodging treatment and collimates the white light.

Optionally, the light source device further includes a polarizer, the polarizer receives the white light emitted in parallel, transmits the white light in the first polarization state to the second dispersive light splitting device, and reflects the white light in the second polarization state to the light collection system.

Optionally, the single micro-projection system further includes a pixel expansion device disposed between the first dispersing beam splitter and the projection lens, for improving the resolution of the single micro-projection system.

The beneficial effect of this application is: different from the prior art, the single micro-transparent panel is provided with the first dispersion light-splitting device behind, and the main light rays of red light, green light and blue light are guided, so that the divergence angles of the red light, the green light and the blue light are reduced, and the expansion of the single micro-transparent projection system is maintained.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic diagram of an embodiment of a color LCD panel of the prior art;

FIG. 2 is a schematic view of a specific structure of the color filter film of FIG. 1;

FIG. 3 is a schematic diagram of a first embodiment of a micro-transillumination projection system of the present application;

FIG. 4 is a schematic view of the illumination divergence angle of the emergent rays of the micro-transmission panel of the present application;

FIG. 5 is a schematic structural diagram of a first embodiment of a first dispersive optical device according to the present application;

FIG. 6 is a schematic diagram of the relationship between the tilt angle and the beam deflection angle of the first sub-device of the present application;

FIG. 7 is a schematic diagram of the relationship between the tilt angle of the first sub-device and the number of layers of the first dispersive optical device according to the present application;

FIG. 8 is a schematic diagram of the relationship between the pitch angle of the first sub-device and the diffraction angle distance of the light beam;

FIG. 9 is a schematic diagram of a second embodiment of the transflective projection system of the present application;

FIG. 10 is a schematic structural diagram of an embodiment of polarizer of the present application;

FIG. 11 is a schematic structural diagram of a third embodiment of the transflective projection system of the present application;

FIG. 12 is a schematic view of a fourth embodiment of the present application;

fig. 13 is a schematic structural diagram of a fifth embodiment of the single micro-transillumination projection system of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It is to be understood that the specific embodiments described herein are merely illustrative of the application and are not limiting of the application. It should be further noted that, for the convenience of description, only some of the structures related to the present application are shown in the drawings, not all of the structures. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The terms "first", "second", etc. in this application are used to distinguish between different objects and not to describe a particular order. Furthermore, the terms "include" and "have," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus.

In addition, the terms "first" or "second", etc. used in this specification are used to refer to numbers or ordinal terms for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the feature. In the description of the present specification, "a plurality" means at least two, for example, two, three or more, and the like, unless specifically defined otherwise.

In recent years, color liquid crystal panels are widely used in the display fields of televisions, computer monitors, mobile phone screens and the like, wherein a single-chip color liquid crystal projection system is an emerging projection system.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a color liquid crystal panel in the prior art, and as shown in fig. 1, the color liquid crystal panel includes an upper polarizer, an upper glass, a color filter, a transparent electrode, an upper alignment film, a liquid crystal layer, a lower alignment film, a TFT pixel matrix transparent electrode, a lower glass, and a lower polarizer, which are sequentially disposed.

Specifically, when white light emitted by the white light source enters the color liquid crystal panel, the white light passes through the lower polarizer to form polarized light, the polarized light sequentially passes through the lower glass, the TFT pixel matrix transparent electrode, the lower alignment film, the liquid crystal layer, the upper alignment film, the transparent electrode, the color filter film and the upper glass to form red light, green light and blue light, and the red light, the green light and the blue light are emitted after being subjected to polarization detection by the upper polarizer.

Please refer to fig. 2, wherein fig. 2 is a schematic structural diagram of the color filter film shown in fig. 1. As shown in fig. 2, the color filters include a red filter, a green filter and a blue filter, which are disposed adjacent to each other, and polarized light passes through different color filters to form an arrangement of red, green and blue color sub-pixels, which are adjacent to each other, and a group of red, green and blue color sub-pixels is equivalent to one color pixel.

When a cylindrical microlens array is attached to an LCD (Liquid Crystal Display), one of the microlens arrays covers three pixels in the horizontal dimension, so that as long as RGB illumination light separated in angle in one dimension but overlapped on the surface is time-superimposed under the condition that every three 1/3 frames of color image light are spatially displaced, 1 frame of red, green and blue pixel overlapped color image can be formed.

However, since the color filter only transmits light of a specific color, light of other wavelengths is completely absorbed, resulting in a large amount of light energy loss (more than 60%). Meanwhile, absorbed light is converted into heat, so that the temperature of the color liquid crystal panel is increased, and the display effect and the service life of a display chip are further influenced; also, the color liquid crystal panel employs a set of three pixels of red, green, and blue equivalent to one color pixel, resulting in a reduction of the resolution of the liquid crystal panel to 1/3, which is the intrinsic resolution.

Meanwhile, the manufacture of the LCD includes two processes of Low Temperature Poly-silicon (LTPS) and High Temperature Poly-silicon (HTPS), and the LCD generally uses the manufacturing process of the LTPS due to Low production cost of the LTPS. However, the pixel size is large (usually above 25 um) due to the Low precision of LTPS-LCD (Low Temperature Poly-silicon-Liquid Crystal Display). Under the condition of a certain resolution, the size of the whole LCD panel is large, so that the size of a subsequent lens is large, and finally the size of the whole projection system is large. In addition, there is no way to make a microlens array near the liquid crystal pixel in the process of LTPS-LCD, and a double-microlens system is formed with the attached microlens array, so that the light will be in a divergent posture after passing through the pixel because the single-microlens array converges the light through the pixel. Therefore, the F number of the lens is reduced, and a lens with a larger aperture needs to be manufactured to ensure the system efficiency. Therefore, the technical solution often has problems of pixel crosstalk and image display disorder in application, and the efficiency of the whole optical system is very low, and very high light source power is required to achieve usable display brightness, and the volume and cost of the larger optical system, the heat dissipation system and the more serious pixel crosstalk come along with the high-power light source.

The application provides a single little projection system, reduces the divergence angle of camera lens incident ray, and increase camera lens incident ray F number maintains single little projection system's extension, improves single little projection system's system efficiency simultaneously.

Referring to fig. 3, fig. 3 is a schematic structural diagram of a first embodiment of a single micro-transillumination projection system of the present application. As shown in fig. 3, the single micro-transmissive projection system 1 includes a light source device 11, a single micro-transmissive panel 12, a first dispersive optical device 13, and a projection lens 14.

The light source device 11 is used for generating a first light beam, and the first light beam at least includes red light, green light and blue light. Specifically, in the present embodiment, the first light beam includes red light, green light, and blue light, wherein the red light, the green light, and the blue light are separated in angular space but coincide on the incident surface of the single micro-transparent panel 12.

The single micro-transparent panel 12 includes a micro-lens array 121 and an LCD panel 122, the micro-lens array 121 is disposed on the LCD panel 122 and covers red pixels, green pixels and blue pixels of the LCD panel 122, and the red pixels, the green pixels and the blue pixels are equivalent to one color pixel. The LCD panel 122 is an LTPS-LCD.

The single micro-transparent panel 12 receives the red light, the green light and the blue light generated by the light source device 11, and the red light, the green light and the blue light converge on the red pixel, the green pixel and the blue pixel respectively and are emitted after being modulated by the red pixel, the green pixel and the blue pixel. The red pixel, the green pixel and the blue pixel form a color pixel, and the chief ray of the red light of the adjacent color pixel emitted by the single micro-transparent panel 12 intersects with the chief ray of the blue light.

With further reference to fig. 4 in conjunction with fig. 3, fig. 4 is a schematic view of the illumination divergence angle of the emergent light of the micro-transmission panel of the present application. As shown in fig. 4, the included angle between the principal ray of the red light and the principal ray of the green light, and the included angle between the principal ray of the blue light and the principal ray of the green light emitted from the single micro-transparent panel 12 are θ₁The half angle of the exit of the single micro-transparent panel 12 is θ₂。

To increase the light transmission through the single micro-transparent panel 12, the angle of the parallel white light needs to be limited, and a schematic diagram of one large pixel in the single micro-transparent panel 12 is shown in fig. 4, wherein one large pixel is composed of three pixels, a red pixel, a green pixel and a blue pixel. Let the size of a single pixel be x, and the effective light-passing pixel be x_{Light transmission}The effective light passing pixel is slightly smaller than one pixel, and the half angle of the parallel white light is theta_{Half of}The microlens array 121 is spaced apart from the pixels by a distance L, and the glass refractive index is n.

When parallel white light is incident on the single micro-transmissive panel 12 and is not just blocked by the metal conductors of the TFT pixel matrix transparent electrodes of the LCD panel 122, the following is required:

θ_{half of}≤sin^-1[n*sin(tan^-1(x_{Light transmission}/2L))]

For example, when the pixel size x is 19.2um, the distance L from the microlens array 121 to the pixel is 0.5mm, and the refractive index of glass is 1.52, θ_{Half of}When the angle is less than or equal to 1.672 degrees, the parallel white light can pass through the single micro-transparent panel 12 and is not blocked by the metal wires.

Because a single slightly transmissive panel 12 is used, there is a severe spread of dilution of the parallel white light, especially blue and red light, after it passes through the panel. In order to reduce the burden on the lens, it is necessary to increase the F-number after passing through the single micro-transparent panel 12, and thus there is another limitation to the parallel white light.

Assuming that the size of the large pixel is 3 × x, the distance from the microlens array 121 to the pixel is L, and the glass refractive index is n, the entrance half angle is determined by the following formula:

θ_{lens barrel}＝sin^-1[n*sin(tan^-1(3x/L))]

Wherein the half angle theta of the single micro-transmitting panel 12₂I.e. half angle theta of entering lens_{Lens barrel}。

In a single-micro-transmissive projection system 1, the half-angle of the lens is typically not more than 17 degrees, which would be costly. Theta when the large pixel size is 69.3um, the microlens array 121 to pixel distance is 0.35mm, and the glass refractive index is 1.52_{Lens barrel}17 deg. At this time theta_{Half of}2.39. Many projectors are using lenses with half angles of 12 degrees, and the focal length of the microlenses is 0.5mm when the large pixel size is 69.3um and the refractive index of the glass is 1.52. At this time theta_{Half of}＝1.67°。

In summary, the minimum angle of the collimated white light is 0.057 degrees when the single micro-transmitting panel 12 is 0.5 inches. The minimum angle of parallel white light is 0.028 degrees when the single micro-transparent panel 12 is 1 inch. When the single micro-transmitting panel 12 is 2 inches, the minimum angle of parallel white light is 0.014 degrees.

The first dispersion optical splitter 13 is used for guiding the principal ray of red light, the principal ray of green light, and the principal ray of blue light. With reference to fig. 3-4 and further referring to fig. 5, fig. 5 is a schematic structural diagram of an embodiment of the first dispersive optical device according to the present application.

As shown in fig. 5, the first dispersion splitting device 13 includes a first sub-device 131 and a second sub-device 132, the first sub-device 131 includes one side forming a first wedge structure and the other side forming a first plane, and the second sub-device 132 includes one side forming a second wedge structure and the other side forming a second plane.

The first wedge-shaped structure and the second wedge-shaped structure are embedded, and the first plane and the second plane are arranged in parallel. The red light, the green light and the blue light sequentially pass through the second plane, the second wedge-shaped structure, the first wedge-shaped structure and the first plane when being transmitted to the projection lens 14 through the first dispersion light-splitting device 13.

The material of the first sub-device 131 is a first material, and the material of the second sub-device 132 is a second material. Specifically, the first material is a low-abbe material, the second material is a high-abbe material, the refractive indexes of the first material and the second material for green light are the same, the refractive indexes of the first material and the second material for red light are different, and the refractive indexes of the first material and the second material for blue light are different. When the red light and the blue light pass through the second wedge-shaped structure and the first wedge-shaped structure, the red light and the blue light are deflected, namely the red light and the blue light are deflected through the dispersion light-splitting device by the first material, the second material, the first wedge-shaped structure and the second wedge-shaped structure which are different.

Specifically, the first wedge structure of the first sub-device 131 is made of optical glue or glass, and the second wedge structure of the second sub-device 132 is made by filling the first wedge structure with the second material.

The base angle β, the tilt angle α, and the pitch angle γ of the first sub-device 131 are all factors that affect the deflection angle of the red light and the blue light.

Preferably, the base angle β of the first sub-device 131 is 90 °. When the first sub-device 131 is manufactured by a photo-curing over-molding method, since a certain angle is required for demolding the first sub-device 131, the bottom angle β of the first sub-device 131 may be slightly smaller than 90 °. When the base angle β of the first sub-device 131 deviates more than 90 °, the stray light generated by the red light and the blue light passing through a dispersion light-splitting device is more, which may result in the low efficiency of the single micro-transmissive projection system 1.

Referring further to fig. 6 in conjunction with fig. 3-5, fig. 6 is a schematic diagram illustrating the relationship between the tilt angle of the first sub-device and the beam deflection angle of the present application. As shown in fig. 6, the inclination angle α of the first sub-device 131 is in a positive correlation with the deflection angle, wherein the deflection angle is the deflection angle at which the red light with the dominant wavelength of 615nm is deflected by the dispersive optical splitter.

Specifically, when the inclination angle α is smaller than 45 °, the magnitude of the increase of the deflection angle with the increase of the inclination angle α is small; when the inclination angle α is larger than 45 °, the magnitude of the increase of the deflection angle with the increase of the inclination angle α is large. Therefore, in order to increase the angle of deflection of red light and blue light, the tilt angle α may be increased, preferably greater than 45 °.

To increase the angle of refraction of the red and blue light, the single micro-transmissive projection system 1 may also use a multi-layered first dispersing optical element 13. Referring further to fig. 7, fig. 7 is a schematic diagram illustrating a relationship between a tilt angle of the first sub-device and the number of layers of the first dispersive optical device according to the present application. As shown in fig. 7, when the deflection angle for realizing the red light is 4 °, the inclination angle α has a negative correlation with the number of layers, that is, the smaller the inclination angle α, the more layers are required. When the number of layers of the first dispersing optical splitter 13 is too large, material waste is easily caused, and the usage space of the single micro-transmissive projection system 1 is occupied too much, which increases the cost.

In summary, the first dispersion splitting device 13 with a smaller number of layers is used, and a larger angle is selected as the tilt angle α of the first sub-device 131, so that the red light and the blue light are emitted at a predetermined deflection angle, and the production cost is reduced.

The pitch angle γ affects the overall thickness, geometrical-optical efficiency, and diffraction-optical efficiency of the first dispersion splitting device 13. When the pitch angle γ is too large, the overall thickness of the first dispersion spectroscopic device 13 becomes too thick, and the problems of material waste and spot dispersion occur. Since the first dispersion splitting device 13 includes the first wedge structure of the first sub-device 131 and the second wedge structure of the second sub-device 132, specifically, the pitch angle γ is related to the first wedge structure of the first sub-device 131, and the first wedge structures are different when the pitch angle γ is different.

As shown in fig. 5, the first wedge-shaped structure can be regarded as a transmissive blazed grating, the center of the diffraction profile of which depends on the direction of the primary ray deflection, and the interference 0 order of which depends on the direction of the incident light. The diffraction model is multislice fraunhofer diffraction. The diffraction distribution formula is as follows:

wherein α ═ π asin θ_xA is the slit width, θ_xIs the diffraction angle. With main step large at 0, i.e. theta_xThe center of the zero-order diffraction spot is the geometric optical image point, which is 0.

The multi-slit diffraction is a result of two effects of diffraction and interference, and the angle of the interference order can be calculated by the formula dsin θ ═ m λ (m ═ 0, ± 1, ± 2, … …), and d is the slit width a. Since the slit width a in the first dispersion splitting device 13 is equal to the pitch of two adjacent slopes in the first wedge structure, the angular distance of each interference order can be approximated by θ ═ m λ/a.

With reference to fig. 3-5 and with further reference to fig. 8, fig. 8 is a schematic diagram of the relationship between the pitch angle of the first sub-device and the diffraction angle distance of the light beam according to the present application. As shown in fig. 8, when the pitch angle γ of the first sub-device 131 is too small, the angular distance of each interference order is 0.6 °, and for light with a specific wavelength, which has a specific deflection angle after passing through the first dispersion splitting device 13, there will be two interference orders with high energy distribution, and the two angles have a large difference, even larger than the light deflection angle, so that many angles exceed the range that the single micro-transparent panel 12 can collect, and the efficiency of the single micro-transparent projection system 1 is reduced.

In some embodiments, the light source device 11 is a pure laser, and the size of the pitch angle γ and the deflection angle need to be optimized at this time, so that the interference order coincides with the 0 th order of the diffraction distribution, and the energy utilization rate is further maximized.

In some embodiments, the light source device 11 is a broad spectrum light, in particular LED or laser fluorescence, where a larger pitch angle γ is chosen to reduce the angle between orders and make the diffraction distribution narrower; or the light deflection angle of each layer of the first dispersion optical splitting device 13 is properly increased to reduce the proportion occupied by diffraction, thereby minimizing the dilution of the expansion amount.

Alternatively, the master model of the first dispersion spectroscopic device 13 may be directly prepared by laser direct writing, precision lathe machining, or the like. The master mold of the first dispersive optical device 13 can also be used for large-area preparation of the first dispersive optical device 13 by preparing a large-area thin mold and performing structure repeated engraving by adopting a roll-to-roll method.

Referring to fig. 9 in addition to fig. 3, fig. 9 is a schematic structural diagram of a second embodiment of the micro-transillumination projection system of the present application. As shown in fig. 9, the light source device 11 includes a light emitting source 111, a light collecting system 112, a second dispersive optical device 114, and a polarizer 113, and the single micro-transmissive projection system 1 further includes a pixel expanding device 15.

Specifically, the light-emitting source 111, the light collection system 112, the polarizer 113, the second dispersive optical device 114, the single micro-transparent panel 12, the first dispersive optical device 13, the pixel expansion device 15, and the projection lens 14 are sequentially disposed on the main optical axis of the single micro-transparent projection system 1.

Wherein the light emitting source 111 is used to generate white light. Alternatively, the light source 111 may be an LED, laser fluorescence, or pure laser.

The light collection system 112 collects the white light so that the white light exits in parallel. Alternatively, the light collection system 112 may be a combination of an integrator rod and an optical magnification system, a fly's eye, or a collection lens group.

Specifically, in the present embodiment, the light collection system 112 includes a light uniformizing device 1121 and a lens assembly 1122.

The dodging device 1121 receives the white light generated by the light emitting source 111, and performs dodging on the white light to shape the white light. Optionally, the light unifying device 1121 is a tapered light unifying device 1121.

The lens assembly 1122 receives the homogenized white light, and collimates the white light to make the emitted white light parallel and uniform. The angle of the white light emitted in parallel is determined by the area of the light emitting surface of the light emitting source 111 and the area of the illumination surface of the single micro-transparent panel 12.

The polarizer 113 receives the parallel and uniform white light emitted from the light collection system 112, transmits the white light in the first polarization state to the second dispersive optical splitting device 114, and reflects the white light in the second polarization state to the light collection system 112. With reference to FIG. 3 and with further reference to FIG. 10, FIG. 10 is a schematic structural diagram of an embodiment of the polarizer of the present application.

As shown in fig. 10, the polarizer 113 includes a reflection region 1132 and a polarization region 1131, and the reflection region 1132 is disposed around the polarization region 1131. When the circular illumination spot 1133 is irradiated on the polarizer 113, a part of the illumination spot 1133 is irradiated on the polarization region 1131, and the other part is irradiated on the reflection region 1132.

The reflection region 1132 is configured to reflect white light, and the light collection device is further configured to collect the white light reflected by the reflection region 1132, transmit the reflected white light to the light emitting source 111, and re-disperse the white light into lambertian natural light, so that the single micro-transmissive projection system 1 reuses the natural light to make the light become recycled light, thereby improving the efficiency of the single micro-transmissive projection system 1. Alternatively, the reflective region 1132 may be a mirror.

Specifically, since the single micro-transmission panel 12 is generally rectangular, a rectangular illumination spot is required to improve the illumination efficiency, the shape of the polarization region 1131 of the present embodiment is matched with the shape of the single micro-transmission panel 12, that is, the polarization region 1131 is set to be rectangular, so that the illumination spot of the white light emitted from the polarizer 113 is a rectangular illumination spot. Meanwhile, the area of the polarization region 1131 is set to be smaller than the area of the illumination light spots 1133, so that the illumination light spots 1133 can fully cover the polarization region 1131, and the illumination light spots 1133 are prevented from failing to fully cover the polarization region 1131, so that the illumination efficiency is low; and the white light irradiated on the reflection region 1132 by the illumination light spot 1133 is reflected to the light collection device, so that light recycling is realized, and the light utilization rate and the working efficiency of the single micro-transmission projection system 1 are further improved.

As shown in fig. 9, the second dispersion splitting device 114 receives the white light transmitted by the polarizer 113 to split the white light into red, green, and blue light. Wherein the red, green and blue light are separated in angular space and coincide on the receiving surface of the single micro-transmitting panel 12.

The second dispersive optical device 114 and the first dispersive optical device 13 have the same structure, and the second dispersive optical device 114 and the first dispersive optical device 13 are symmetrically arranged relative to the single micro-transparent panel 12.

Specifically, the second dispersion optical splitting device 114 includes a third sub-device including one side forming a third wedge structure and the other side forming a third plane, and a fourth sub-device including one side forming a fourth wedge structure and the other side forming a fourth plane. And the material of the third sub-device is a first material, and the material of the fourth sub-device is a second material. Specifically, the first material is a low abbe material and the second material is a high abbe material.

The third wedge-shaped structure and the fourth wedge-shaped structure are embedded, and the third plane and the fourth plane are arranged in parallel. The red light, the green light and the blue light sequentially pass through the third plane, the third wedge structure, the fourth wedge structure and the fourth plane when being transmitted to the single micro-transparent panel 12 through the second dispersion light-splitting device 114.

The single micro-transparent panel 12 receives the red light, the green light and the blue light emitted by the second dispersion light-splitting device 114, and forms image information according to the red light, the green light and the blue light.

Further, the first dispersion splitting device 13 is disposed at an intersection position of a principal ray of red light of a certain color pixel and a principal ray of blue light of an adjacent color pixel, so that the intersecting red light and blue light are guided and emitted in parallel. Meanwhile, by matching with the pixel expansion device 15 arranged behind the first dispersion light-splitting device 13, the resolution is improved by a time division multiplexing method, and the screen window effect caused by too long distance between the green pixel and the red pixel and between the green pixel and the blue pixel is reduced. Alternatively, the Pixel extension means 15 may be an XPR (extended Pixel Resolution) device or an E-SHIFT (Pixel expansion of birefringent crystals) device.

The projection lens 14 receives the guided red light, green light and blue light to image the image information on the single micro-transparent panel 12 on the screen, thereby realizing color projection imaging.

Referring to fig. 11, fig. 11 is a schematic structural diagram of a third embodiment of a single micro-transillumination projection system of the present application. As shown in fig. 11, the light emitting source 211 of the present embodiment is a laser fluorescence light source, and the light emitting source 211 includes a blue laser 2111, a first dodging device 2112, a lens 2113 and a fluorescence wheel 2114, which are different from the above embodiments.

Specifically, the blue laser 2111 generates blue laser light; the blue laser is transmitted to the first light homogenizing device 2112, and the first light homogenizing device 2112 homogenizes the blue laser and emits the blue laser to the lens 2113; the lens 2113 converges the blue laser light onto the fluorescent wheel 2114; the yellow phosphor disposed on the fluorescence wheel 2114 is excited to emit white fluorescence, and is transmitted to the light collection system 112 for subsequent processing and imaging.

Referring to fig. 12, fig. 12 is a schematic structural diagram of a fourth embodiment of a single micro-transillumination projection system of the present application. As shown in fig. 12, the light source 311 of the present embodiment includes a blue laser 3111, a second dodging device 3112, a beam splitter 3113, a first light source 3114, a second light source 3115, a first lens group 3116, a second lens group 3117 and a third lens group 3118, which is different from the above embodiments.

Optionally, the second light source 3115 is a blue light source for generating blue-based light. Alternatively, the first light source 3114 may be a fixed fluorescent sheet, wherein the fixed fluorescent sheet is a yellow fluorescent sheet; or the first light source 3114 may be an LED light source with a surface coated with green phosphor, red phosphor, or yellow phosphor.

In this embodiment, when the fixed fluorescent sheet is used as the first light source 3114, it is beneficial for the first light source 3114 to dissipate heat; in this embodiment, when the LED coated with phosphor is used as the first light source 3114, the first light source 3114 can be excited on both sides, so as to improve the excitation efficiency of the phosphor.

Specifically, the blue laser 3111 generates blue laser, the second dodging device 3112 performs dodging on the blue laser and emits the blue laser to the beam splitter 3113, the beam splitter 3113 reflects the blue laser, the first lens group 3116 converges the reflected blue laser to the first light source 3114, and the first light source 3114 is excited to emit white fluorescence and transmits the white fluorescence to the beam splitter 3113; the second light source 3115 generates blue light, and transmits the blue light to the spectroscope 3113 through the second lens assembly 3117; the beam splitter 3113 transmits the white fluorescence and reflects the blue primary light, and transmits the light to the light collection system 112 through the third lens assembly 3118 for subsequent imaging.

Referring to fig. 13, fig. 13 is a schematic structural diagram of a fifth embodiment of a single micro-transillumination projection system according to the present application. As shown in fig. 13, different from the above embodiments, the light emitting source 411 of the present embodiment includes a first laser 4111, a second laser 4112, a third laser 4113, a first reflector 4114, a second reflector 4115, a third reflector 4116, a first lens 4117, and a gaussian scattering wheel 4118. Wherein, the gaussian scattering wheel 4118 is a large-angle gaussian scattering wheel.

In this embodiment, the first laser 4111, the second laser 4112, and the third laser 4113 are red laser, blue laser, and green laser. In this embodiment, the first laser 4111 is not limited to red laser, the second laser 4112 is blue laser, and the third laser 4113 is green laser, and the positions of the red laser, the blue laser, and the green laser may be changed in other embodiments.

Specifically, the first laser 4111 generates red laser light, which is transmitted to the first lens 4117 through the first reflector plate 4114, the second reflector plate 4115, and the third reflector plate 4116 in sequence; the second laser 4112 generates blue laser, which is transmitted to the first lens 4117 through the second reflector 4115 and the third reflector 4116 in sequence; the third laser 4113 generates green laser light, which is transmitted to the first lens 4117 by the third reflector 4116; the first lens 4117 focuses the red, blue, and green laser light onto the gaussian scattering wheel 4118 to despeckle the pure laser light and emit red, blue, and green light to the light collection system 112 for subsequent processing and imaging.

In the embodiment, the light emitting source 411 uses three different colors of a first laser 4111, a second laser 4112, and a third laser 4113, so that the brightness of the red light, the green light, and the blue light finally output by the gaussian scattering wheel 4118 is higher; meanwhile, the working current of the first laser 4111, the second laser 4112 and the third laser 4113 can be controlled independently in this embodiment, the intensity of the laser beam output by the first laser 4111, the second laser 4112 and the third laser 4113 is controlled, and the color gamut of the single micro-transparent projection system 1 is adjustable.

In the single micro-transparent projection system 1, the first dispersion light-splitting device 13 is arranged behind the single micro-transparent panel 12 to guide the principal ray of red light, the principal ray of green light and the principal ray of blue light, so as to reduce the divergence angles of the red light, the green light and the blue light and maintain the expansion of the single micro-transparent projection system 1. The first dispersion spectroscopic device 13 is low in cost and high in efficiency, and can improve the projection efficiency of the single micro-transmissive projection system 1.

Meanwhile, the shape of the polarization region 1131 of the polarizer 113 is matched with that of the single micro-transparent panel 12, so that a high-efficiency illumination light spot is provided. And the area that sets up polarization area 1131 is less than the area of illumination facula for the illumination facula can the total coverage polarization area 1131, and the white light that the illumination facula shines on reflection area 1132 reflects to light collection device, realizes light cyclic utilization, further improves single little light utilization ratio and the work efficiency who passes through projection system 1.

The above embodiments are merely examples, and not intended to limit the scope of the present application, and all modifications, equivalents, and flow charts using the contents of the specification and drawings of the present application, or those directly or indirectly applied to other related arts, are included in the scope of the present application.

Claims

1. A single micro-transillumination projection system, comprising:

a light source device for generating a first light beam, the first light beam comprising at least red light, green light and blue light;

the single micro-transparent panel receives the red light, the green light and the blue light, and the emergent principal ray of the red light and the principal ray of the green light are intersected with the principal ray of the blue light;

the first dispersion light-splitting device is used for guiding the principal ray of the red light, the principal ray of the green light and the principal ray of the blue light;

2. The single micro-transillumination projection system of claim 1, wherein the first dispersing optical device comprises a first sub-device and a second sub-device, the first sub-device is made of a first material, the second sub-device is made of a second material, the first material and the second material have the same refractive index for the green light, the first material and the second material have different refractive indices for the red light, and the first material and the second material have different refractive indices for the blue light, so that the red light and the blue light are deflected by the first dispersing optical device.

3. The single micro-transillumination system of claim 2, wherein the first sub-device comprises one side forming a first wedge-shaped structure and the other side forming a first plane, the second sub-device comprises one side forming a second wedge-shaped structure and the other side forming a second plane, the first wedge-shaped structure is embedded with the second wedge-shaped structure, the first plane is parallel to the second plane, and the red light, the green light and the blue light sequentially pass through the second plane, the second wedge-shaped structure, the first wedge-shaped structure and the first plane.

4. The single micro-transillumination projection system of claim 3, wherein the red light and the blue light are deflected to produce a deflection angle, the first sub-device comprising a pitch angle, a tilt angle, and a base angle;

wherein, the pitch angle, the angle of inclination with the base angle sum is 180, base angle less than or equal to 90, the base angle with the deflection angle is the negative correlation, the angle of inclination with the deflection angle is positive correlation, the pitch angle with the deflection angle is the negative correlation.

5. The single transflective projection system according to claim 1, wherein the single transflective projection system comprises at least two of the first dispersing optical devices, the at least two first dispersing optical devices being arranged in a stack.

6. The single transflective projection system according to claim 1, wherein the single transflective panel is a LTPS-LCD.

7. The single micro-transillumination system of claim 6, wherein the single micro-transillumination panel comprises a micro-lens array and an LCD panel, the micro-lens array is disposed on the LCD panel and covers red pixels, green pixels and blue pixels of the LCD panel, so that the red light, the green light and the blue light converge on the red pixels, the green pixels and the blue pixels, respectively.

8. The single micro-transillumination system according to claim 7, wherein the red pixel, the green pixel and the blue pixel constitute a color pixel, and the first dispersing optical device is disposed at an intersection position of a principal ray of the red light and a principal ray of the blue light emitted from two adjacent color pixels.

9. The single micro-transillumination projection system of claim 7, wherein the projection lens satisfies the following relationship:

θ_{lens barrel}＝sin^-1[n*sin(tan^-1(3x/L))]

Wherein, theta_{Lens barrel}The half-angle of incident light of the projection lens is the lens entering half-angle, x is the pixel size of the red pixel, the green pixel or the blue pixel, L is the distance from the micro-lens array to the red pixel, the green pixel or the blue pixel, and n is the glass refractive index of the projection lens.

10. The single micro-transillumination system of claim 1, wherein the light source device comprises:

a light emitting source for generating white light;

the light collection system is used for collecting the white light so as to enable the white light to be emitted in parallel;

and the second dispersion light-splitting device receives the white light so as to decompose the white light into the red light, the green light and the blue light.

11. The single micro-transmissive projection system of claim 10, wherein the second dispersing optical element is identical in structure to the first dispersing optical element, and the second dispersing optical element and the first dispersing optical element are symmetrically disposed with respect to the single micro-transmissive panel.

12. The single micro-transillumination projection system of claim 10, wherein the light collection system comprises:

13. The single micro-transmissive projection system of claim 10 wherein the light source device further comprises a polarizer for receiving the white light exiting in parallel, transmitting the white light of a first polarization state to the second dispersive optical device, and reflecting the white light of a second polarization state to the light collection system.

14. The single micro-perspective projection system according to claim 1, further comprising a pixel extension device disposed between the first dispersing optical device and the projection lens for increasing a resolution of the single micro-perspective projection system.