CN115708014A - Light combining module for non-telecentric illumination and projection device - Google Patents

Abstract

The application protects a close optical module for non-telecentric illumination, includes: the light combining prism comprises a first coated surface and a second coated surface vertical to the first coated surface, and the first coated surface and the second coated surface transmit second illumination light; the first coating surface and the second coating surface are sequentially divided into a first section of coating, a second section of coating, a third section of coating and a fourth section of coating along the clockwise direction; the first section of coating film and the third section of coating film reflect the first illumination light and transmit the third illumination light, and the second section of coating film and the fourth section of coating film reflect the third illumination light and transmit the second illumination light; the spectrum of the reflecting film of the coating section is obtained by blue shift or red shift of a preset distance along a preset direction according to the non-telecentric angle and the standard incident angle of the first illuminating light and the third illuminating light respectively; and the spectrums of the transmission films of the first film coating surface and the third film coating surface are blue-shifted or red-shifted by a preset distance along a preset direction according to the non-telecentric angle and the standard incident angle of the second illumination light. Thereby, a ray shift of the non-telecentric illumination is avoided.

Description

Light combination module for non-telecentric illumination and projection device

Technical Field

The application relates to the technical field of display, in particular to a light combining module and a projection device for non-telecentric illumination.

Background

With the improvement of information technology, people have higher and higher requirements on visual appreciation. "visual impact" is a criterion for judging display performance. The visual impact is not only from a clear picture but also from an oversized picture. To meet such a demand, large-screen display has come to be used. Taking a living room as an example, the market sales in recent years show that the size of a liquid crystal television tends to increase gradually. However, the coming of the information age has resulted in time fragmentation, and the living room is no longer the only place for video entertainment, and because of the large size and weight of the lcd tv, it cannot be applied anywhere and anytime. On the other hand, although the mobile phone screen has advanced in size, and even a larger-sized smart tablet dedicated for entertainment appears, it is limited to its display mode, and it is difficult to realize a real large-screen display. Therefore, flexible large-screen display is realized, and only a technical route of projection is provided at present.

The projection display system mainly comprises a lighting system, an optical-mechanical system, a projection lens and other main parts. Spatial light modulators, also referred to as "light valves," in opto-mechanical systems are critical devices. Light valves are generally pixilated planar devices, each of which can independently modulate incident illumination light by transmission or reflection, and thus modulate the luminous flux of each pixel, forming a display image. Projection Display systems are roughly classified into a reflective DMD (Digital Micro-Mirror Device) projection, a transmissive LCD (Liquid Crystal Display) projection, and a reflective LCoS (Liquid Crystal on Silicon) projection, according to the type of spatial light modulator. The spatial light modulator is classified into a single-chip projection, a two-chip projection, and a three-chip projection.

As is well known, the core principle of display is to adopt the display principle of three primary colors of red, green and blue, i.e. image display information of the three primary colors of red, green and blue needs to be displayed respectively by a light valve, and then three monochromatic images are combined in a time integral (generally, monolithic projection) or space integral (generally, three-piece projection) manner, so that human eyes can observe information of a single color image. However, the method using time integration is easily limited by the "rainbow effect", and thus, is not an optimal solution for realizing large-screen display.

The three-sheet projection can fundamentally solve the problem of rainbow effect. However, the three-chip projection scheme has the problems of complex optical path system, high hardware cost, large system volume and the like, and therefore, how to fundamentally solve the disadvantages of complex optical path, high cost, large volume and the like of the three-chip projection is a problem to be solved urgently by those skilled in the art.

Disclosure of Invention

In view of the above drawbacks of the prior art, the present application provides a low-cost light combining module for non-telecentric illumination, in which the light combining module for non-telecentric illumination includes: the light combining prism comprises a first coated surface and a second coated surface vertical to the first coated surface, and the first coated surface and the second coated surface transmit second illumination light; the first coating surface and the second coating surface are sequentially divided into a first section of coating, a second section of coating, a third section of coating and a fourth section of coating along the clockwise direction; the first section of coating film and the third section of coating film reflect first illumination light and transmit third illumination light, and the second section of coating film and the fourth section of coating film reflect third illumination light and transmit second illumination light; the spectrums of the reflecting films of the first section of coating film and the third section of coating film are blue-shifted or red-shifted by a preset distance along a preset direction according to the non-telecentric angle and the standard incident angle of the first illuminating light; blue shift or red shift of the spectrum of the reflective film of the second coating section and the spectrum of the reflective film of the fourth coating section along a preset direction by a preset distance according to the non-telecentric angle and the standard incident angle of the third illumination light; and the transmission film spectrums of the first film coating surface and the third film coating surface are blue-shifted or red-shifted by a preset distance along a preset direction according to the non-telecentric angle and the standard incident angle of the second illumination light.

In some embodiments, the range of the angles of incidence of the first, second, and third illumination light is less than the sum of the standard angle of incidence and the non-telecentric angle and greater than the difference between the standard angle of incidence and the telecentric angle.

In some embodiments, when the range of the incidence angles of the first illumination light, the second illumination light and the third illumination light increases from the standard incidence angle, the reflection film spectrum and the transmission film spectrum of the light combination prism are blue-shifted to the blue wavelength direction; when the range of the incidence angles of the first illumination light, the second illumination light and the third illumination light increases and decreases from the standard incidence angle, the spectrum of the reflection film and the spectrum of the transmission film of the light combination prism are red-shifted to the blue wavelength direction.

In some embodiments, the predetermined distance is dependent on the wavelength range of the illumination light, the non-telecentric angle of the illumination light, and the thickness of the reflective film layer or the transmissive film layer.

In some embodiments, the first range of the spectrum of the reflective film of the x-cube after shifting with angle of incidence is greater than and encompasses the spectral range of the illumination light.

In some embodiments, the non-telecentric angle is in the range 0 < θ < 45 °.

In some embodiments, the first and third sections of the coating film have a coating film thickness of 500nm, an illumination light spectrum range of 622nm to 700nm, a predetermined distance of 60nm, and a reflective film spectrum range of 562nm to 760nm.

In some embodiments, the second and fourth sections of coating films have a coating film thickness of 500nm, an illuminating light spectrum range of 455nm to 488nm, a predetermined distance of 30nm, and a reflective film spectrum range of 425nm to 513nm.

In another aspect, the present application further provides a projection apparatus, including: the light source module comprises a plurality of light source modules, and the light source modules are used for emitting a first light beam, a second light beam and a third light beam; the liquid crystal modulation module comprises a plurality of liquid crystal modulation modules which are arranged on an emergent light path of the light source module and are used for respectively modulating the first light beams, the second light beams and the third light beams emitted by the light source modules into first image light, second image light and third image light; in any of the above embodiments, the light combining module for non-telecentric illumination is disposed on the light emitting paths of the plurality of liquid crystal modulation modules, and is configured to combine the first illumination light formed by the first image light, the second illumination light formed by the second image light, and the third illumination light formed by the third image light to generate color image light; the light beam converging assembly is arranged between the light source module and the light combining module and is used for converging or partially converging the light beam to realize non-telecentric illumination; the light combining module is arranged on the emergent light paths of the liquid crystal modulation modules and is used for combining the first image light, the second image light and the third image light to generate colorful image light; and the projection lens is arranged on an emergent light path of the light combination module and used for imaging the image light onto a preset projection plane or a screen so as to display an image.

In some embodiments, the first light beam, the second light beam and the third light beam irradiate the plurality of liquid crystal modulation modules in a non-imaging manner, and the plurality of liquid crystal modulation modules and the light combining module combine light by adopting a short side to reduce the back intercept of the lens.

In some embodiments, the light source module comprises a first light source module, a second light source module and a third light source module; the liquid crystal modulation module comprises a first liquid crystal modulation module, a second liquid crystal modulation module and a third liquid crystal modulation module, wherein the second liquid crystal modulation module is arranged on an emergent light path of the second light source module along a first direction, the first liquid crystal modulation module is arranged on the emergent light path of the first light source module along a second direction perpendicular to the first direction, and the third liquid crystal modulation module is arranged on the emergent light path of the third light source module along the opposite direction of the second direction; the light combining module is arranged on an emergent light path of the second liquid crystal modulation module of the liquid crystal modulation module along the first direction.

In some embodiments, the liquid crystal modulation module comprises a polarizer, a modulation panel and an analyzer, wherein the polarizer is used for polarizing the light beam emitted by the light source module so that the polarization state of the light beam is parallel to the liquid crystal direction of the modulation panel, and the analyzer is used for analyzing the light beam modulated by the modulation panel to be recognized by human eyes.

In some embodiments, the modulation panel is a LTP-LCD.

In some embodiments, the first liquid crystal modulation module, the second liquid crystal modulation module, and the third liquid crystal modulation module respectively include a first modulation panel, a second modulation panel, and a third modulation panel, and a long side direction of the second modulation panel is perpendicular to the first direction, parallel to long side directions of the first modulation panel and the third modulation panel, and perpendicular to a short side direction of the light combining module.

In some embodiments, each of the first light source module, the second light source module, and the third light source module of the light source module includes a light emitting unit, a light collecting unit, and a collimating lens, where the light emitting unit is configured to emit a light beam, the light collecting unit is configured to collect the light beam emitted by the light emitting unit and emit the light beam in a non-imaging manner, and the collimating lens is configured to collimate the light beam emitted by the light collecting unit.

In some embodiments, the light source module further comprises a supplementary second light source module, the supplementary second light source module is arranged along the second direction and comprises a supplementary second light emitting unit along the second direction; the first light source module is arranged along a second direction, the second light source module is arranged along a first direction, the third light source module is arranged along a direction opposite to the second direction, and the complementary light emitted by the complementary second light source module and the second light beam emitted by the second light source module are combined and then irradiate the second liquid crystal modulation module.

In some embodiments, a supplementary light combining unit is disposed on a common exit path of the second light emitting unit and the supplementary second light emitting unit of the second light source module, and the supplementary light combining unit is configured to reflect a supplementary light beam emitted by the supplementary second light emitting unit to the second light emitting unit and transmit a second light beam emitted by the second light emitting unit.

In some embodiments, the reflective surface of the second light-emitting unit is coated with a phosphor excited to emit the second light beam, and the supplementary light beam is a blue laser.

In some embodiments, the first light source module is disposed along a first direction, the second light source module is disposed along the first direction, the third light source module is also disposed along the first direction, the first light beam emitted from the first light source module is reflected by the first reflection element and then enters the first liquid crystal modulation module along a second direction, and the light beam emitted from the third light source module is reflected by the third reflection element and then enters the third liquid crystal modulation module along a direction opposite to the second direction.

In some embodiments, the projection lens is a non-telecentric ultra-short focus lens, and the non-telecentric ultra-short focus lens is of an asymmetric structure.

Compared with the prior art, because the first section coating film, the second section coating film, the third section coating film and the fourth section coating film of the prism are respectively subjected to coating film design, the spectrums of the reflecting films of the first section coating film and the third section coating film are blue-shifted or red-shifted by a preset distance along a preset direction according to the non-remote center angle and the standard incident angle of the first illumination light; blue shift or red shift of the spectrum of the reflective film of the second coating section and the spectrum of the reflective film of the fourth coating section along a preset direction by a preset distance according to the non-telecentric angle and the standard incident angle of the third illuminating light; and the transmission film spectrums of the first coating film surface and the third coating film surface are blue-shifted or red-shifted by a preset distance along a preset direction according to the non-telecentric angle and the standard incident angle of the second illumination light, so that light ray shift during non-telecentric illumination can be avoided, the wavelength of light rays irradiated to the lens under the non-telecentric illumination cannot be changed, and the color uniformity of the illumination light is further ensured.

Drawings

FIG. 1 is a schematic diagram of a basic optical architecture of a projection apparatus;

fig. 2 is a schematic structural diagram of a first embodiment of a projection apparatus according to the present application;

fig. 3 is a schematic structural diagram of long-side light combination and short-side light combination in the present application;

fig. 4 is a schematic structural diagram of a projection apparatus 110 according to a second embodiment of the present application;

FIG. 5 is a diagram showing the ray traces of parallel light (telecentric illumination light) irradiating the light-combining prism and non-telecentric illumination light irradiating the light-combining prism;

FIG. 6 is a schematic diagram illustrating wavelength shift of a reflection spectrum of the projection apparatus 110 according to a second embodiment when the reflection spectrum varies with an incident angle;

fig. 7 is a schematic structural diagram of a projection apparatus 120 according to a third embodiment of the present application;

fig. 8 is a schematic structural diagram of a projection apparatus 130 according to a fourth embodiment of the present application;

fig. 9 is a schematic structural diagram of a projection apparatus 140 according to a fifth embodiment of the present application;

fig. 10 is a schematic structural view of a polarizer 241g according to embodiment five of the present application;

fig. 11 is a schematic structural diagram of a projection apparatus 150 according to a sixth embodiment of the present application;

FIG. 12 is a schematic view of the structure of a polarizer 251g according to a sixth embodiment of the present application;

fig. 13 is a schematic structural diagram of a projection apparatus 160 according to a seventh embodiment of the present application;

fig. 14 is a schematic structural diagram of a projection apparatus 170 according to an eighth embodiment of the present application;

Detailed Description

In the display field, since the DMD and the LCOS are respectively manufactured by a complex process and a high cost, and both are reflective devices, when applied to a three-chip type projection, the light path is more complex, and the volume is difficult to further reduce, therefore, the projection architecture of the three-chip type LCD is always a commonly used projection scheme in the three-chip type, however, the conventional projection architecture of the three-chip type LCD still has the problems of high cost and large volume.

At present, an LCD panel is divided into HLTP-LCD and LTP-LCD according to two processes of Low Temperature Poly-Silicon (LTPS) and High Temperature Poly-Silicon (HTPS), wherein the HTPS process has High precision, the core HTPS process is mostly mastered in foreign and friend vendors, the size of a liquid crystal pixel can reach less than 10um, and the aperture ratio and the resolution ratio are High, which can meet the size requirement of a projector on a light valve, but the HTPS has extremely High requirement on the preparation process, so the cost is High, and meanwhile, the panel requires a light source with a small enough expansion amount, and generally adopts a bulb or a laser as the light source, which causes the size of the light machine to be large.

The LTP-LCD panel prepared by the LTPS is also called a color modulation panel, and has high productivity in China due to simple process and low cost. However, since the process is simple and the precision is low, the pixel size is usually above 25um, and the panel is large, that is, in the case of a certain resolution, the size of the whole LTP-LCD panel is large, and the size of the subsequent lens is large, which finally results in a large size of the whole projection apparatus, the LTP-LCD is generally applied to the monolithic projection, and never applied to the three-piece projection.

It should be noted that the actual protection cases and technical solutions of the technical problems specifically solved by the claims of the present application are mainly described in the second to sixth embodiments, and the other embodiments are the premise or extension of the solutions specifically protected by the claims of the present application, and are not considered as the prior art, but are shown only for the purpose of clearly stating the inventive concepts of the technical problems actually solved by the present application.

Therefore, the application provides a new projection architecture, a scheme of illuminating three-piece LTP-LCDs in a non-imaging mode and combining short sides is adopted, the requirement on small optical expansion of an incident light source is reduced, the technical defect of the three-piece projection architecture caused by large panel size of the LTP-LCD is solved from the technical aspect, the technical bias that the panel size of the LTP-LCD is large and the LTP-LCD cannot be applied to the three-piece projection architecture is overcome, the problems that the traditional three-piece HLTP-LCD architecture is high in cost, difficult to produce in volume, large in size, difficult to adapt to civilized projection application scenes such as commercial teaching and household use and the like are solved, the large-panel LTP-LCD capable of producing in volume is really applied to the three-piece projection architecture, and the rapid industrialization of middle and low-end projection products in the projection display industry is accelerated. It can be understood that the projection device of the application can be used for projectors such as business machines and education machines in the traditional projection industry, can be more preferably applied to micro projectors, mobile phone integrated projection and the like due to simple structure and strong functions, and has very wide application prospects.

Referring to fig. 1, a basic optical architecture of a projection apparatus according to the present application is shown, the projection apparatus includes a light source module 10, a liquid crystal modulation module 20, a light combining module 30, and a projection lens 40. The light source module 10 includes a plurality of light source modules, and can respectively emit a first light beam, a second light beam, and a third light beam, where the first light beam, the second light beam, and the third light beam are respectively red light, green light, or blue light; the liquid crystal modulation module 20 comprises a plurality of liquid crystal modulation modules, is arranged on an emergent light path of the light source module 10, and is used for respectively modulating light beams such as a first light beam, a second light beam, a third light beam and the like into a first image light, a second image light and a third image light, wherein the first light beam, the second light beam and the third light beam are respectively emitted from the light source module 10 and then enter the plurality of liquid crystal modulation modules of the liquid crystal modulation module 20 in a non-imaging mode, so that the number and the distance of elements from the light source module 10 to the display module 20 are greatly reduced, and the volume of the illumination system can be effectively reduced; the light combination module is arranged on the emergent light path of the liquid crystal modulation modules and is used for combining the first image light, the second image light and the third image light modulated by the liquid crystal modulation modules to generate colorful image light; the projection lens 40 is disposed on an exit light path of the light combining module, and is configured to image the image light onto a preset projection plane or a screen to display an image. Taking the direction of the image light entering the projection lens as the first direction as an example, the plurality of liquid crystal modulation modules and the light combining module of the liquid crystal modulation module 20 combine light by adopting a short-edge light combining (which is the short-edge light combining will be described in detail later), so that the volume of the light combining module 30 in the first direction can be reduced, the back intercept of the projection lens 40 is also effectively reduced, and the volume of the whole projection device is greatly reduced.

The embodiments of the present application will be described in detail below with reference to the drawings and embodiments.

Fig. 2 is a schematic structural diagram of a first embodiment of a projection apparatus according to the present application. The projection apparatus 100 includes a light source module 10, a liquid crystal modulation module 20, a light combining module 30 and a projection lens 40, wherein the light source module 10 includes a first light source module 10r, a second light source module 10g and a third light source module 10b, which are respectively configured to emit a first light beam, a second light beam and a third light beam, in some embodiments, the first light beam is red light, the second light beam is green light, and the third light beam is blue light, the light source module 10 may be a laser or an LED, or may also adopt a scheme of laser fluorescence, and the application does not limit the specific type of the light source module 10; the liquid crystal modulation module 20 includes a first liquid crystal modulation module 20r, a second liquid crystal modulation module 20g, and a third liquid crystal modulation module 20b, which are respectively used for modulating a first light beam, a second light beam, and a third light beam that are provided with a non-imaging mode and irradiate the liquid crystal modulation module 20, wherein in some embodiments, the first liquid crystal modulation module 20r, the second liquid crystal modulation module 20g, and the third liquid crystal modulation module 20b all adopt LTP-LCD modules, so that a larger modulation area can be provided, and requirements for the expansion amount of the light beam incident on the liquid crystal modulation module 20 are reduced; the first light beam, the second light beam and the third light beam modulated by the first liquid crystal modulation module 20r, the second liquid crystal modulation module 20g and the third liquid crystal modulation module 20b are respectively represented as a first image light, a second image light and a third image light, and the first image light, the second image light and the third image light are respectively incident to the light combination module 30 and then combined into a color image light, and are imaged on a preset projection plane through the projection lens 40.

The first light source module 10r, the second light source module 10g and the third light source module 10b are respectively used for emitting a first light beam, a second light beam and a third light beam. The first light source module 10r enters the light combining module 30 along a second direction perpendicular to the first direction, the second light source module 10g enters the light combining module 30 along the first direction, and the third light source module 10b enters the light combining module 30 along a direction opposite to the second direction. In the present embodiment, since the first light source module 10r, the second light source module 10g and the third light source module 10b are the same in component and only different in relative position from the light combining module 30, taking the second light source module 10g as an example, the second light source module 10g includes a second light emitting unit 101g, a light collecting unit and a collimating lens 103g sequentially arranged along the first direction. In the present embodiment, the second light emitting unit 101g is a green laser for emitting green light.

In this embodiment, the light collection unit is a conical reflector 102g, the end of the conical reflector 102g with the smaller area is an incident surface, and the end with the larger area is an emergent surface, so that the green light emitted by the second light emitting unit 101g is incident into the conical reflector through the incident surface, and then is emitted by the emergent surface or directly emitted after being reflected by the side wall of the conical reflector, so that the area of the emergent light spot is larger than that of the incident light spot, thereby reducing the divergence angle of the light beam, and irradiating the second light beam onto the second liquid crystal modulation module in a non-imaging manner. The conical reflector 102g in this embodiment is a solid conical light guide rod, and light beams are reflected on the side surface of the conical reflector 102g in a total reflection manner. In other embodiments of the present application, the conical reflector 102g may also be a hollow conical reflector composed of a reflective plate/surface, which is not described herein again.

The outgoing light from the conical reflector 102g of the present embodiment is irradiated onto the collimator lens 103g, so that the second light beam is collimated and smoothly enters the optical element downstream of the optical path. It will be appreciated that in other embodiments of the present application, the collimating lens may not be provided, for example, where the second light beam from the upstream optical path satisfies a small divergence angle.

In some embodiments, a light recycling assembly (not shown) may be further disposed between the conical reflector 102g and the collimating lens 103g, or after the collimating lens 103g, in this case, taking the conical reflector 102g and the collimating lens 103g as an example, if the light emitted by the second light-emitting unit 102g is unpolarized green light, part of the light is transmitted through the light recycling assembly and then continuously emitted in a single polarization state, and part of the light is reflected by the light recycling assembly and then returns to the conical reflector 102g, is reflected back and forth in the conical reflector 102g, and is emitted again through the emitting surface of the conical reflector 102g to reach the light recycling assembly, that is, the light recycling assembly is configured to selectively transmit a single polarization state according to the polarization state of the light emitted by the second light-emitting unit, and recycle light in another polarization state, so as to improve the utilization rate of the first light beam. It can be understood that if the second light emitting unit 102g employs LED or laser fluorescence, the above structure can re-disperse the polarized light returned from the light recycling assembly into natural light, and then continue to participate in light circulation. In some embodiments, in order to reduce the recycling times of the recycled first light beam, a structure such as a 1/4 wave plate (not shown) may be disposed in the conical reflector to change the polarization state of the light beam. In the present application, the light recovery component may be a device such as a wire grid polarizer. Similarly, the first light source module 10r includes a first light emitting unit 101r, a conical reflector 102r, and a collimating lens 103a, which are sequentially disposed along the second direction, and the first light emitting unit 101a is a red laser; the third light source module 10b includes a third light emitting unit 101a, a conical reflector 102b and a collimating lens 103b, which are disposed along the second direction in an opposite direction, the third light emitting unit 101b is a red laser, and the specific principle is similar to that of the second light source device 10g, and is not described herein again.

Continuing to refer to fig. 2, taking the second light source module 10g as an example, the first light beam from the second light source module 10g is incident to the second liquid crystal modulation module 20g, and the second liquid crystal modulation module 20g includes a polarizer 201g and a second modulation panel 202g, where the polarizer 201g is configured to control a polarization state of the second light beam, so that the polarization state of the second light beam is parallel to a liquid crystal direction of the second modulation panel 202g, so that the second modulation panel 202g can modulate the second light beam to generate the second illumination light, in this embodiment, the second modulation panel 202g includes an analyzer (not shown) disposed on a rear surface thereof, and the analyzer is configured to analyze the second illumination light modulated by the second modulation panel 202g, so as to be recognized by human eyes. The second illumination light generated after being modulated by the second modulation panel 202g is irradiated to the light combining module 30 along the first direction, and similarly, the first illumination light generated after being modulated by the first modulation panel 202a is irradiated to the light combining module 30 along the second direction, and the third illumination light generated after being modulated by the third modulation panel 202b is irradiated to the light combining module 30 along the opposite direction of the second direction. Next, the relative positions of the first modulation panel 202a, the second modulation panel 202g, and the third modulation panel 202b and the light combining module 30 will be described.

Please refer to fig. 3, which is a schematic structural diagram of long-side light combination and short-side light combination according to the present application. It will be appreciated that to achieve superior display performance, the standard aspect ratio of an LTP-LCD panel is typically 16:9,16: 10,4:3, the LTP-LCD panel is not square, but has long and short sides. Meanwhile, in the three-panel projection, the specifications of the three panels should be consistent except for different modulation colors. In the long-side light combination mode shown in fig. 3 (r), the long-side direction of the green light panel is parallel to the first direction and is perpendicular to the long-side directions of the red light panel and the blue light panel, respectively, and at this time, the distance from the green light panel to the projection lens 40, that is, the back intercept of the projection lens 40 is at least equal to the length of the long sides of the red light panel and the blue light panel. In the short-side light combination scheme shown in fig. 3 (g), the long side direction of the second modulation panel 202g is perpendicular to the first direction and parallel to the long side directions of the first modulation panel 202a and the third modulation panel 202b, so that the back intercept from the first modulation panel 202a to the projection lens 40 is at least equal to the short side lengths of the first modulation panel 202a and the third modulation panel 202 b.

With reference to fig. 3, the light combining module 30 is configured to combine the first illumination light, the second illumination light, and the third illumination light, and it can be understood that, when the scheme of combining the short sides is adopted, the light combining module 30 may adopt an X-cube light combining prism, where the light combining prism includes a first coated surface (not shown) and a second coated surface perpendicular to the first coated surface, the first coated surface and the second coated surface are sequentially divided into a first segment coated film 311, a second segment coated film 312, a third segment coated film 313, and a fourth segment coated film 314 along a clockwise direction, the first segment coated film 311 is a green-transparent and red-reflective film, the second segment coated film 312 is a red-green-transparent and blue-reflective film, the third segment coated film 313 is a blue-green-transparent and red-reflective film, and the fourth segment coated film 314 is a green-transparent and blue-reflective film.

Meanwhile, the long side direction of the light combining prism is parallel to the long side direction of the second modulation panel 202g, the long side length of the light combining prism is greater than or equal to the long side direction of the second modulation panel 202g, the short side direction of the light combining prism is parallel to the short side direction of the second modulation panel 202g, and the short side length of the light combining prism is greater than or equal to the short side direction of the second modulation panel 202g, when the light combining module 30 is projected along the direction perpendicular to both the first direction and the second direction, the light combining module 30 is in an "X" shape, wherein the "X" shape is a projection line of the first coated surface and the second coated surface. With this arrangement, the first illumination light and the third illumination light are reflected in the first direction, respectively, and combined with the second illumination light to generate colored illumination light.

The projection lens 40 is disposed on the light emitting path of the light combining module 30, and is used for projecting the color image to a predetermined position to form an image that can be viewed by a viewer. In the present embodiment, the projection lens 40 is composed of a plurality of lenses. It can be understood that a person skilled in the art can design a product lens according to a projection scene requirement, and the projection lens may further include optical structures such as a reflective curved surface, which will not be described herein again.

In some embodiments, a pixel expansion module 50 may be further disposed between the light combining module 30 and the projection lens 40, and the pixel expansion module 50 is configured to translate the light beams of the color images along a direction perpendicular to the optical axis, so that the color images at different translation positions are temporally overlapped, so as to improve the display resolution of the final projection. The Pixel expansion module 50 may be a transparent flat plate optical device (XPR) whose rotation angle is controlled by current or voltage, and when the transparent flat plate of the Pixel expansion module 50 rotates a certain angle, the light passing through the transparent flat plate is refracted twice and then translated integrally, and the transparent flat plate stays at the rotation position for a predetermined time and then rotates to other positions. In one image frame period, the pixel expansion module 50 may include 2 or 4 stable states, the image is divided into 2 or 4 sub-frames in response, and the human eye superimposes the captured 2 or 4 images through a time integration function to form a high-resolution image in the brain, thereby realizing a 4K or 1080P high-resolution projection display. It will be appreciated that the pixel shifting arrangement may also include more stable states to achieve higher resolution, and the number of pixel multiplications is not limited by the present application.

In other embodiments, the pixel shifting device may also be a liquid crystal birefringence device, and the deflection angle of liquid crystal molecules is controlled by voltage, so that light passing through the liquid crystal birefringence (E-shift) device is translated, thereby implementing the effect of shifting the whole pixel, the effect is similar to that of the above mechanically rotated pixel shifting device, and details are not repeated here.

It can be understood that, in the above scheme, since the light source module 10 adopts the non-imaging mode to irradiate the liquid crystal modulation module 20, the distance from the light source module 10 to the liquid crystal modulation module 20 is relatively small, and the size of the illumination system is effectively reduced, and meanwhile, since the light combining scheme of combining light by the short side is adopted, the light combining structure of the light combining module 30 itself can be fully utilized, the back intercept from the first modulation panel 202a to the projection lens 40 is greatly reduced, and the volume of the whole projection apparatus is reduced. However, since the color illumination light emitted from the light combining module 30 is still telecentric illumination light to illuminate the lens, the lens usually has an offset (offset) of 100% or more, and therefore, for a telecentric illumination system, the lens diameter d needs to be satisfied

Wherein, L is the panel effective illumination area length, and W is the panel effective illumination area width, which makes the lens size still not small enough, with high costs, thereby limiting the further miniaturization of the whole projection device. For this reason, the present application also proposes a more preferable solution in which the volume is further reduced.

Specifically, please refer to fig. 4 illustrating a schematic structural diagram of a projection apparatus 110 according to a second embodiment of the present application, and fig. 4 illustrates a modified embodiment of the first embodiment illustrated in fig. 2, so that components and numbers identical to those of fig. 2 are referred to for description in the first embodiment. The difference between this embodiment and the first embodiment is that, in this embodiment, a light beam converging component is added in the projection apparatus. The light beam converging component can be arranged at any position between the collimating lens of the light source module and the light combining module and is used for converging or partially converging the illumination light beam. With reference to fig. 4, taking an example of a light path from the second light source module 11g to the light combining module 30, the second light beam converging component 213g is disposed between the polarizer 211g of the second liquid crystal modulation module 21g and the second modulation panel 212g, so as to shape the collimated green parallel light emitted from the second light source module 11g into a light beam converged or partially converged along the main optical axis of the first direction and irradiate the light combining module, that is, the panel and the light combining module are irradiated in a non-telecentric illumination manner, preferably, the second light beam converging component 213g may be attached to the polarizer 211g and the second modulation panel 212 g. Similarly, the first light source module 10a and the third light source module 10b are also arranged in the same manner, that is, the first light beam converging assembly 213r and the third light beam converging assembly 213b are respectively arranged at corresponding positions, so as to realize the non-telecentric illumination light combining module 30, further reduce the distance from the light source module to the light combining module along the first direction, the second direction and the direction opposite to the second direction, and reduce the volume of the whole illumination system.

In some embodiments, the light beam converging component may be a field lens, a fresnel lens, or a free-form lens, although not limited thereto, as long as the optical element is capable of converging or partially converging the first light beam.

In this embodiment, since the beam converging assembly is added in front of the light combining module, when the illumination light enters the light combining module 30, the illumination light is shaped into a non-telecentric beam converging along the main optical axis or partially converging, so that the effective illumination area when the illumination light reaches the lens is greatly reduced, thereby reducing the diameter of the lens and greatly reducing the volume of the whole illumination system.

However, when the technical problem needs to be further solved, the non-telecentric illumination mode adopted in the second embodiment needs to further consider the film coating property of the light combining module. Please refer to fig. 5, which shows the ray traces of the parallel light (telecentric illumination light) and the non-telecentric illumination light when they are irradiated to the light-combining prism. To the x-ray prism that this application adopted, along with the increase of light incident angle, the effective optical thickness of x-ray prism's coating film rete can reduce along with the angle of light oblique incidence rete, leads to the reflectance spectrum or the transmission spectrum of rete to short wave direction removal. That is, as shown in fig. 5 (a), taking the first light beam and the first illumination light as parallel light beams as an example, when the parallel first illumination light is combined by the light combining prism, the incident angle of the light beam with respect to the reflection surface of the first-stage plated film 311 and the third-stage plated film 313 of the light combining prism is the standard incident angle α, for example, α =45 °, and at this time, the reflection spectrum of the first-stage plated film 311 and the third-stage plated film 313 is basically unchanged; for the non-telecentric illumination light, as shown in fig. 5b, the incident angle of the first illumination light irradiated on the reflective surfaces of the first segment plating film 311 and the third segment plating film 313 changes, and when the non-telecentric angle is θ, the incident angle of the light ray changes between 45 ° ± θ, and therefore, the reflection spectra of the first segment plating film 311 and the third segment plating film 313 also change accordingly.

In order to solve the above technical problem, please refer to the schematic diagram of the wavelength shift of the reflection spectrum varying with the incident angle shown in fig. 6, in this embodiment, the first, second, third and fourth sections of the coating films 311, 312, 313 and 314 of the light combining prism are subjected to coating design. For the non-telecentric illumination shown in fig. 5 (b), it is assumed that the film layers of the first section of plating film 311, the second section of plating film 312, the third section of plating film 313 and the fourth section of plating film 314 are all designed according to a standard 45 ° incident angle, wherein, taking the first section of plating film 311 as a green-transparent red-reflective film and the third section of plating film 313 as a blue-green red-reflective film as an example, the wavelength range of the reflective plating film is set as the first wavelength λ ₁ To a second wavelength lambda ₂ And the spectral range of the first illumination light is a third wavelength lambda ₃ To a fourth wavelength λ ₄ In between. When the incident angle of the first illumination light is increased to 45 degrees plus theta, the reflection spectrum of the coating film is moved to the blue light wavelength, namely blue shift, and at the moment, the reflected wavelength range is changed into that the first wavelength and the second wavelength are both moved to the blue light wavelength direction by a preset distance delta lambda ₁ 、Δλ ₂ A blue-shifted spectral curve as shown in FIG. 6 that is optically oriented relative to the telecentric illumination standard spectral curve shown in FIG. 6The left end of the spectral coordinate axis is shifted and denoted as λ ₁ - Δλ ₁ ～λ ₂ -Δλ ₂ (ii) a When the incident angle of the first illumination light is reduced to 45-theta, the reflection spectrum of the coating film is moved towards the red wavelength direction, namely red shift, and at the moment, the reflected wavelength range is changed into a first wavelength and a second wavelength which are respectively moved towards the red wavelength direction by a preset distance delta lambda ₁ 、Δλ ₂ The red-shifted spectral curve shown in FIG. 6 is shifted to the right end of the spectral coordinate axis relative to the standard spectral curve of telecentric illumination shown in FIG. 6 and is denoted by λ ₁ + Δλ ₁ ～λ ₂ +Δλ ₂ . Wherein, the above-mentioned Delta lambda ₁ 、Δλ ₂ The size of (b) depends on the wavelength range of the first illumination light, the non-telecentric angle theta of the first illumination light, the plating film thicknesses of the first-stage plating film 311 and the third-stage plating film 313, and the like. Since the beam converging element is a symmetric element, the non-telecentric angle θ of the first illumination light is generally symmetrically offset, i.e., Δ λ ₁ ＝Δλ ₂ 。

In order to ensure that the wavelength of the illumination light emitted after the first illumination light is combined by the light combining prism is not changed, that is, the color of the illumination light is uniform, the coating film needs to satisfy λ ₃ ＞λ ₁ +Δλ ₁ And λ of ₄ ＜λ ₂ -Δλ ₂ Condition (b), i.e. the narrowest lambda of the reflection spectrum after a shift with angle of incidence ₁ +Δλ ₁ ～λ ₂ -Δλ ₂ Is larger than and includes the spectral range lambda of the first illumination light ₃ ～λ ₄ The narrowest range of these ranges may be referred to as the first range.

In this embodiment, when the thickness is 500nm in the case of vapor deposition, λ is the value for reflecting the first illumination light, i.e., red light ₃ ＝622nm，λ ₄ ＝700nm，λ ₁ +Δλ ₁ ＜ 622nm、λ ₂ -Δλ ₂ > 700nm, then Δ λ ₁ /θ＝Δλ ₂ The theta is approximately equal to 20nm/5 degrees, wherein the theta is more than 0 and less than 45 degrees, and if the non-center angle is 15 degrees, the plating ranges of the first section of plating film 311 and the third section of plating film 313 are preferably 562nm to 760nm; with respect to the reflection of the third illumination light,i.e. blue light, lambda ₃ ＝455nm，λ ₄ ＝ 488nm，λ ₁ +Δλ ₁ ＜455nm、λ ₂ -Δλ ₂ ＞488nm，Δλ ₁ /θ＝Δλ ₂ The theta is approximately equal to 10nm/5 degrees, wherein the theta is more than 0 and less than 45 degrees, and if the non-center angle is 15 degrees, the coating ranges of the first section of coating film 311 and the third section of coating film 313 are preferably 425 nm-513 nm.

Similarly, for the film segment of the transmission coating film, the wavelength range of the transmission spectrum after the shift along with the incident angle of the illumination light is also required to be larger than and include the spectrum range of the illumination light, so as to ensure the color uniformity of the illumination light, and the coating principle is consistent with the range setting of the reflection coating film, which is not described herein again.

In this embodiment, the coating film for the light-combining prism satisfies the spectrum range λ of the reflection spectrum of the coating film after being shifted with the incident angle of the illumination light ₁ +Δλ ₁ ～λ ₂ -Δλ ₂ Range greater than and including the spectral range lambda of the illumination light ₃ ～λ ₄ The relationship of (1) can avoid light deviation caused when the non-telecentric illumination light beam irradiates the common light-combining prism, so that the wavelength of light irradiating the lens under the non-telecentric illumination cannot be changed, and the color uniformity of the illumination light is further ensured.

It can be understood that, in some embodiments, in order to avoid the above-mentioned complicated modification manner of the coating process, a light beam converging component may not be disposed in the space between the first light source module 11r, the second light source module 11g, the third light source module 11b and the light combining module, but a light beam converging component may be disposed between the light combining module 30 and the projection lens 40, so as to irradiate uniform illumination light into the lens.

In the second embodiment, after the first light source module 11r, the second light source module 11g, and the third light source module 11b emit the first light beam, the second light beam, and the third light beam respectively, the light beams are converged by the first light beam converging assembly 213r, the first light beam converging assembly 213g, and the third light beam converging assembly 213b, and then are converged by the light converging module and projected through the lens. However, in this apparatus, when the LED is used as the light emitting element, the second light emitting element 111g has a problem of low conversion efficiency, and thus, under the same condition, the second light beam emitted from the second light source module is significantly weaker than the first light source module and the third light source module. Therefore, the application further improves the light path setting of the second light source module aiming at the problem.

Specifically, please refer to a schematic structural diagram of a projection apparatus 120 according to a third embodiment of the present application shown in fig. 7, which is similar to the embodiment shown in fig. 4, except that: in this embodiment, the light source module further includes a supplementary second light source module 12b1, the supplementary second light source module 12b1 is disposed along the second direction, and the structure of the supplementary second light source module 12g (the second light emitting unit 121g, the light collecting unit 122g and the collimating lens 123g sequentially disposed along the first direction) is substantially the same, and the supplementary second light emitting unit (not identified in the figure), the light collecting unit (not identified in the figure) and the collimating lens (not identified in the figure) are included, and the difference is only that the supplementary second light emitting unit of the supplementary second light source module emits blue laser, and the outer side surface of the second light emitting unit 121g is a reflection surface and is coated with a green emitting material, such as green phosphor. And a complementary light combining unit 320g is disposed on a common exit path of the second light source assembly 12g and the complementary second light source assembly 12b1, the complementary light combining unit 320g is provided with a film layer for reflecting blue laser and transmitting red and green fluorescence, and is configured to reflect blue laser emitted by the complementary second light source assembly 12b1 to green phosphor of the second light emitting assembly 121g, and excite green fluorescence, so as to cooperate with the second light emitting assembly to emit green light with higher brightness, that is, by additionally disposing the complementary second light source assembly 12b1, two-sided excitation can be performed on the green phosphor on the second light emitting assembly 121g, which is helpful for improving excitation efficiency of excited laser, and further improving light efficiency.

Optionally, the supplementary light combining unit 320g may also be configured as an area film (not shown) including a middle area and an edge area, the middle area is configured to reflect blue laser light with a smaller etendue and complementary to the second light source assembly onto the second light emitting assembly, and the edge area is configured to transmit green light emitted by the second light emitting assembly and green fluorescence generated by excitation of green phosphor on the second light emitting assembly by the blue laser light. In this way, the conversion and utilization efficiency of the green light of the double-sided excitation can be further improved.

Further, in order to further reduce the schematic optical path structure of the second embodiment, a fourth embodiment is further proposed in the present application, please refer to fig. 8, which is a schematic structural diagram of a projection apparatus 130 of the fourth embodiment of the present application, and the present embodiment is similar to the embodiment shown in fig. 4, except that: the first light source module and the third light source module of this embodiment are both disposed along the first direction, but the first liquid crystal modulation module 23r (including the polarizer 231r and the first modulation panel 232 r) and the first light beam converging component 233r are still disposed along the second direction, and the third liquid crystal modulation module 23b (including the polarizer 231b and the third modulation panel 232 b) and the third light beam converging component 233b are still disposed along the opposite direction of the second direction, and a first folding component is further disposed between the first light source module and the first liquid crystal modulation module 23r, and the first folding component includes a first light recycling component 631r, a first light transmitting device 632r, and a first folding component 633r for adjusting the transmission direction of the first light beam from the first direction to the second direction.

Specifically, the first light recycling assembly 631 is configured to transmit light of a first polarization state of the first light beam emitted by the first light source module and reflect light of a second polarization state perpendicular to the first polarization state, so as to further achieve light recycling, and optionally, the first light recycling assembly 631 may adopt a reflective polarization antireflection film (DBEF); a first light transmission device 632r is disposed in the emergent direction of the first light recycling assembly 631, and is used for transmitting the first light beam to the first turning element 633r without loss, in some embodiments, the first light transmission device may adopt a hollow light guide device, a square rod, a conical rod, or the like; the first turning element 633r may be a solid right-angle prism for turning the transmission direction of the first light beam transmitted in the first direction to be transmitted in the second direction, thereby compressing the volume along the projection apparatus in the second direction.

Furthermore, when the first refractive element 633r is of a hollow structure, the first refractive element includes an incident surface, a reflecting surface and an emergent surface, the incident surface and the emergent surface may be made of coated glass, quartz or plastic, and may be in the shape of a straight plane, a curved surface or a sawtooth surface formed by a plurality of straight planes, and the two may be placed at mutually perpendicular positions to satisfy the requirements of transmission and reflection of different light rays.

The included angle between the reflecting surface of the first turning element 633r and the first direction can be any angle between-90 degrees and 0 degrees, so that the light can be turned to any direction. Preferably, when the angle between the reflecting surface and the first direction is-45 °, the light is folded by 90 °, so that the direction of the first light beam is folded into the second direction.

Similarly, a third turning component is further disposed between the third light source module and the third liquid crystal modulation module 23b, and includes a third light recycling component 631b, a third light transmission device 632b, and a third turning element 633b for adjusting the transmission direction of the third light beam from the first direction to the opposite direction of the second direction. Meanwhile, the angle between the reflecting surface of the third turning element 633b and the first direction may be any angle between 0 ° and 90 °. The rest of the settings are substantially the same as the settings from the first light source module to the light combining module, and are not described herein again.

The transmission direction of the first light beam transmitted along the first direction is converted into the transmission direction along the second direction and the transmission direction of the third light beam is adjusted from the first direction to the opposite direction of the second direction, the space from the second light source module to the light combining device along the first direction can be fully utilized, the problem that the size of the first light source module and the third light source module along the second direction is too large when the first light source module and the third light source module are arranged is solved, meanwhile, the light recovery assembly, the light transmission device and the conversion element are included in the conversion assembly, the first light beam can be efficiently and nondestructively transmitted to the liquid crystal modulation module, and the light utilization efficiency is effectively improved on the premise that the size of the device is reduced.

Referring to fig. 9, a schematic structural diagram of a projection apparatus 140 according to a fifth embodiment of the present application is shown, which is similar to the embodiment shown in fig. 4 except that: the light collection unit of the embodiment adopts the second lens 142g, the second lens 142g is a collection lens and is used for collecting light emitted by the second light emitting component and emitting collimated first light beams under the collimation effect of the collimating lens, and because the surface distribution of the first light beams emitted by the second lens 142g and the collimating lens is circular, and the part of the modulation panel requiring illumination is rectangular, the rectangular part needs to be cut out of a circular light spot, and the light spot shaping and the light ray recovery are realized by the polarizer 241g with a special shape. As shown in fig. 10, the polarizer 241g includes a circular speckle pattern 2411g, a first region 2412g and a second region 2413g. Preferably, the circular spot surface distribution 2411g is a spot shape when the first light beam is transmitted to the modulation panel, the first area 2412g is a rectangular area which is adapted to the modulation panel shape and is inscribed in the circular spot, and 2412g is set as an optical recycling film layer for recycling polarized light of the rectangular area light spot of the first light beam, for example, the above-mentioned DBEF is used, so that the system efficiency is maximally improved, the second area 2413g is set at an edge part of the circular spot surface distribution 2412g of the polarizer 241g except the first area, and the second area 2413g may be a mirror reflection film layer, so that the edge light spot part which does not participate in illumination in the circular spot is reflected back to the second lens 142g for reuse, thereby further improving the light utilization efficiency.

Through the arrangement, the first light beam can be divided into the rectangular light spot used for irradiating the modulation panel and the edge light spot which is reflected and recycled, so that the light with different areas and different polarization characteristics can be recycled and reused from space and polarization dimension, and the light utilization efficiency of the light emitted by the light source module is ensured to the maximum extent.

Referring to fig. 11, a schematic structural diagram of a projection apparatus 150 according to a sixth embodiment of the present application is shown, which is similar to the embodiment shown in fig. 9 except that: in this embodiment, the second lens is a free-form surface lens, preferably an XY polynomial lens, the collimating lens 153g is a fresnel lens, and the free-form surface lens is used as the second lens to make the surface distribution of the outgoing light a rectangle slightly larger than the illumination area of the modulation panel, so as to match with the illumination portion required by the panel. Therefore, the polarizer 251g is provided in a structure as shown in fig. 12, including a circular rectangular spot surface distribution 2511g, a first region 2512g, and a second region 2513g. Preferably, the circular rectangular spot surface distribution 2511g is a spot shape when the first light beam is transmitted to the modulation panel, the first region 2512g is a rectangular region adapted to the modulation panel and inscribed in the circular rectangular spot, and 2512g is set to be a light circulation film layer for performing polarized light circulation on the rectangular region spot of the first light beam, for example, the above-mentioned DBEF is adopted, so that the system efficiency is maximally improved, the second region 2513g is arranged at the edge part of the circular rectangular spot surface distribution 2512g of the polarizer 251g except the first region, and the second region 2513g can be a mirror reflection film layer, so that the edge spot part of the circular spot not participating in illumination can be reflected back to the second lens for reuse, thereby further improving the light utilization efficiency. Due to the combination of the free-form surface lens and the Fresnel lens, the circular light spot can be shaped into the circular rectangular light spot, the area of the edge area is reduced, and compared with the fifth embodiment, the light loss efficiency of reflected light at the edge area is reduced, so that higher light utilization efficiency is realized.

Referring to fig. 13, a schematic structural diagram of a projection apparatus 160 according to a seventh embodiment of the present application is shown, which is similar to the embodiment shown in fig. 4 except that: in this embodiment, an ultra-short-focus lens is further disposed on the basis of the second embodiment shown in fig. 4, and includes a reflector 462 and a reflective cup 461, so as to deflect the illumination light beam, thereby avoiding that the lens is too long and the size of the system becomes large. The projection device can increase the space utilization rate after folding light, reduce the volume of the projection device, effectively solve the problems of large volume, high cost and the like of an illumination system adopting the direct projection lens, and simultaneously adopt the ultra-short focal lens to ensure that the distance from the projection device to a projection surface under the condition of the same transmittance is less than that of an optical machine using the direct projection lens, thereby reducing the space occupied by the projection device when a user uses the projection device and improving the user experience.

Referring to fig. 14, a schematic structural diagram of a projection apparatus 170 according to an eighth embodiment of the present application is shown, which is similar to the embodiment shown in fig. 8 and 13, except that: in this embodiment, an ultra-short-focus lens is further disposed on the basis of the fourth embodiment shown in fig. 8, and compared with the seventh embodiment, the structural layout of this embodiment can further utilize the space from the second light source module to the lens along the first direction, thereby further reducing the volume of the projection apparatus.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

The above description is only an embodiment of the present application, and not intended to limit the scope of the present application, and all modifications of equivalent structures and equivalent processes performed by the contents of the specification and the drawings, or applied to other related technical fields directly or indirectly, are included in the scope of the present application.

Claims (20)

1. A light combining module for non-telecentric illumination, comprising:

the light combining prism comprises a first coated surface and a second coated surface perpendicular to the first coated surface, and the first coated surface and the second coated surface transmit second illumination light;

the first coating surface and the second coating surface are sequentially divided into a first section of coating, a second section of coating, a third section of coating and a fourth section of coating along the clockwise direction; the first section of coating film and the third section of coating film reflect first illumination light and transmit third illumination light, and the second section of coating film and the fourth section of coating film reflect third illumination light and transmit second illumination light; wherein the content of the first and second substances,

the spectrums of the reflecting films of the first section of coating film and the third section of coating film are blue-shifted or red-shifted by a preset distance along a preset direction according to the non-telecentric angle and the standard incident angle of the first illumination light;

blue shift or red shift of the spectrum of the reflective film of the second coating section and the spectrum of the reflective film of the fourth coating section along a preset direction by a preset distance according to the non-telecentric angle and the standard incident angle of the third illumination light; and

and the transmission film spectrums of the first film coating surface and the third film coating surface are blue-shifted or red-shifted by a preset distance along a preset direction according to the non-telecentric angle and the standard incident angle of the second illumination light.

2. A light combining module for non-telecentric illumination according to claim 1, wherein the range of the incident angles of the first illumination light, the second illumination light and the third illumination light is less than the sum of the standard incident angle and the non-telecentric angle and greater than the difference between the standard incident angle and the telecentric angle.

3. A light combining module for non-telecentric illumination according to claim 2,

when the range of the incidence angles of the first illumination light, the second illumination light and the third illumination light is increased from a standard incidence angle, the spectrum of the reflection film and the spectrum of the transmission film of the light combination prism are blue-shifted towards the blue light wavelength direction;

when the range of the incidence angles of the first illumination light, the second illumination light and the third illumination light is increased and decreased from the standard incidence angle, the spectrum of the reflection film and the spectrum of the transmission film of the light combination prism are red-shifted to the blue light wavelength direction.

4. A light combining module for non-telecentric illumination according to claim 1,

the preset distance depends on the wavelength range of the illumination light, the non-telecentric angle of the illumination light and the thickness of the reflective film layer or the transmissive film layer.

5. A light combining module for non-telecentric illumination according to claim 1,

the first range of the spectrum of the reflecting film of the light-combining prism after shifting with the incident angle is larger than and includes the spectral range of the illuminating light.

6. A light combining module for non-telecentric illumination according to claim 1, wherein the non-telecentric angle ranges from 0 < θ < 45 °.

7. The light combining module for non-telecentric illumination according to claim 6, wherein the first and third sections of coating films have a coating film thickness of 500nm, an illumination light spectrum range of 622nm to 700nm, a predetermined distance of 60nm, and a reflective film spectrum range of 562nm to 760nm.

8. The light combining module for non-telecentric illumination according to claim 6, wherein the second and fourth coating films have a coating thickness of 500nm, an illumination light spectrum range of 455nm to 488nm, a predetermined distance of 30nm, and a reflective film spectrum range of 425nm to 513nm.

9. A projection device, comprising:

the light source module comprises a plurality of light source modules, and the light source modules are used for emitting a first light beam, a second light beam and a third light beam;

the liquid crystal modulation modules are arranged on an emergent light path of the light source module and used for respectively modulating the first light beams, the second light beams and the third light beams emitted by the light source modules into first image light, second image light and third image light;

the light combining module for non-telecentric illumination according to any one of claims 1 to 8, wherein the light combining module is disposed on the light outgoing path of the plurality of liquid crystal modulation modules, and is configured to combine the first illumination light formed by the first image light, the second illumination light formed by the second image light, and the third illumination light formed by the third image light to generate the color image light;

the light beam converging assembly is arranged between the light source module and the light combining module and is used for converging or partially converging the light beam to realize non-telecentric illumination;

the light combining module is arranged on the emergent light paths of the liquid crystal modulation modules and is used for combining the first image light, the second image light and the third image light to generate colorful image light; and

and the projection lens is arranged on the emergent light path of the light combination module and is used for imaging the image light onto a preset projection plane or a screen to display an image.

10. A projection device according to claim 9,

the first light beam, the second light beam and the third light beam irradiate the liquid crystal modulation modules in a non-imaging mode, and the liquid crystal modulation modules and the light combination module adopt short-side light combination to reduce the back intercept of the lens.

11. A projection device according to claim 10,

the light source module comprises a first light source module, a second light source module and a third light source module;

the liquid crystal modulation module comprises a first liquid crystal modulation module, a second liquid crystal modulation module and a third liquid crystal modulation module, wherein the second liquid crystal modulation module is arranged on an emergent light path of the second light source module along a first direction, the first liquid crystal modulation module is arranged on the emergent light path of the first light source module along a second direction perpendicular to the first direction, and the third liquid crystal modulation module is arranged on an emergent light path of the third light source module along the opposite direction of the second direction;

the light combining module is arranged on an emergent light path of the second liquid crystal modulation module of the liquid crystal modulation module along the first direction.

12. A projection device according to claim 10,

the liquid crystal modulation module comprises a polarizer, a modulation panel and an analyzer, wherein the polarizer is used for polarizing the light beam emitted by the light source module so as to enable the polarization state of the light beam to be parallel to the liquid crystal direction of the modulation panel, and the analyzer is used for analyzing the light beam modulated by the modulation panel so as to be recognized by human eyes.

13. A projection device as claimed in claim 12, characterized in that the modulation panel is a LTP-LCD.

14. A projection device according to claim 13,

the first liquid crystal modulation module, the second liquid crystal modulation module and the third liquid crystal modulation module respectively comprise a first modulation panel, a second modulation panel and a third modulation panel, wherein the long side direction of the second modulation panel is perpendicular to the first direction, is parallel to the long side directions of the first modulation panel and the third modulation panel, and is perpendicular to the short side direction of the light combination module.

15. A projection device according to claim 11,

the first light source module, the second light source module and the third light source module of the light source module respectively comprise a light emitting unit, a light collecting unit and a collimating lens, wherein the light emitting unit is used for emitting light beams, the light collecting unit is used for collecting the light beams emitted by the light emitting unit and emitting the light beams in a non-imaging mode, and the collimating lens is used for collimating the light beams emitted by the light collecting unit.

16. A projection device according to claim 15,

the light source module also comprises a supplementary second light source module which is arranged along a second direction and comprises a supplementary second light-emitting unit along the second direction; wherein, the first and the second end of the pipe are connected with each other,

the first light source module is arranged along a second direction, the second light source module is arranged along a first direction, the third light source module is arranged along a direction opposite to the second direction, and the supplement light emitted by the supplement second light source module is combined with the second light beam emitted by the second light source module and then irradiates the second liquid crystal modulation module.

17. A projection device according to claim 16,

and a complementary light combining unit is arranged on a common emergent path of a second light emitting unit arranged on the second light source module and the complementary second light emitting unit, and is used for reflecting a complementary light beam emitted by the complementary second light emitting unit to the second light emitting unit and transmitting a second light beam emitted by the second light emitting unit.

18. A projection device according to claim 17,

and fluorescent powder which is excited to emit the second light beam is coated on the reflecting surface of the second light-emitting unit, and the supplementary light beam is blue laser.

19. A projection device according to claim 10,

the first light source module is arranged along a first direction, the second light source module is arranged along the first direction, the third light source module is also arranged along the first direction, a first light beam emitted by the first light source module is reflected by the first reflection component and then is incident to the first liquid crystal modulation module along a second direction, and a light beam emitted by the third light source module is reflected by the third reflection component and then is incident to the third liquid crystal modulation module along a direction opposite to the second direction.

20. The projection apparatus according to claim 9, wherein the projection lens is an telecentric ultra-short-focus lens and the telecentric ultra-short-focus lens is in an asymmetric structure.

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