CN220121133U - Single-chip LCD projection system - Google Patents

Abstract

The application relates to the technical field of projection display, and discloses a single-chip LCD projection system, which is provided with a closed cavity and comprises an illumination module, an optical module, a first fan, a second fan and a heat dissipation mechanism; wherein, the light emitting direction of the lighting module is the same as the light emitting direction of the optical module; at least part of the optical module forms part of the closed cavity; the first fan and the second fan are arranged at intervals on one side of the optical module, which is far away from the lighting module, and are positioned in the closed cavity; the first fan and the second fan are configured to cause an airflow to flow within the enclosed cavity; the heat dissipation mechanism is arranged on the closed cavity; at least part of heat generated by the optical module is transferred to the heat dissipation mechanism through the air flow in the closed cavity and is dissipated outside the closed cavity through the heat dissipation mechanism. By the mode, the heat dissipation uniformity and the heat dissipation efficiency of the single-chip LCD projection system are improved.

Description

Single-chip LCD projection system

Technical Field

The application relates to the technical field of projection display, in particular to a single-chip LCD projection system.

Background

Projection devices have been widely used, and liquid crystal display (Liquid Crystal Display, abbreviated as "LCD") projection systems have been widely used because they allow easy adjustment of screen size, exhibit excellent color reproducibility, and are inexpensive. However, LCD projection systems cannot withstand high brightness due to their easy temperature rise, thereby limiting their wider application.

Disclosure of Invention

Based on the above, the present utility model provides a monolithic LCD projection system with improved heat dissipation performance.

In order to solve the technical problems, the utility model adopts a technical scheme that: a monolithic LCD projection system is provided, which has a closed cavity and comprises an illumination module, an optical module, a first fan, a second fan and a heat dissipation mechanism; the illumination module is configured to emit illumination light; the optical module is arranged on the light emitting side of the illumination module and is configured to at least convert the illumination light into imaging light; the light-emitting direction of the illumination module is the same as the light-emitting direction of the optical module; at least part of the optical module forms part of the closed cavity; the first fan and the second fan are arranged at intervals on one side of the optical module, which is far away from the lighting module, and are positioned in the closed cavity; the first blower and the second blower are each configured to flow gas within the enclosed cavity; the heat dissipation mechanism is arranged on the closed cavity; at least part of heat generated by the optical module is transferred to the heat dissipation mechanism through the air flow in the closed cavity and is dissipated outside the closed cavity through the heat dissipation mechanism.

The technical scheme provided by the application can achieve the following beneficial effects: the application is beneficial to improving the heat radiation uniformity and the heat radiation efficiency of the single-chip LCD projection system by arranging the closed cavity, and can adopt stronger backlight source after the heat radiation effect is improved, thereby improving the brightness of the projector.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art. Wherein:

FIG. 1 is a schematic diagram of a horizontal, monolithic LCD projection system for laterally ventilating a second light-emitting element according to some embodiments of the present application;

FIG. 2 is a schematic diagram of a horizontal, monolithic LCD projection system for vertically ventilating a second light-emitting element according to further embodiments of the present application;

FIG. 3 is a schematic diagram of a vertical, monolithic LCD projection system with lateral ventilation of a second light-emitting element according to some embodiments of the present application;

FIG. 4 is a schematic cross-sectional view taken along line p1 of FIG. 3;

FIG. 5 is a schematic diagram of a vertical, monolithic LCD projection system for vertically ventilating a second light-emitting element according to further embodiments of the present application;

FIG. 6 shows an optical path diagram of illumination light emitted from 3 light emitting elements and corresponding phosphor layers;

FIG. 7 shows the spot distribution of illumination light from a single light emitting element and a corresponding phosphor layer on the illuminated surface;

FIG. 8 shows a state in which illumination light emitted from a plurality of light emitting elements and corresponding phosphor layers are superimposed;

fig. 9 shows an initial state when 3 spots are superimposed;

fig. 10 shows the final state when 3 spots are superimposed;

FIG. 11 is a top view of a collimating lens assembly, a collecting lens assembly, and a light source assembly in a projection system according to some embodiments of the present application;

FIG. 12 is a top view of a collimating lens assembly, a collecting lens assembly, and a light source assembly in a projection system according to further embodiments of the present application;

FIG. 13 is a schematic structural view of at least one dielectric film disposed on at least one surface of a first optical element, a second optical element, and a third optical element disposed at intervals according to some embodiments of the present application;

fig. 14 is a graph showing the relationship between the number of graded layers and the transmittance in the dielectric film.

Detailed Description

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

Projection devices have been widely used, and liquid crystal display (Liquid Crystal Display, abbreviated as "LCD") projection systems have been widely used because they allow easy adjustment of screen size, exhibit excellent color reproducibility, and are inexpensive.

However, LCD projection systems cannot withstand high brightness due to their easy temperature rise, thereby limiting their wider application.

In the related art, a fan is generally directly used to blow the air to the liquid crystal panel, wherein the air flows on the light incident surface and the light emergent surface of the liquid crystal panel are in the same direction. This causes the liquid crystal panel to have uneven temperature, and tends to have a low temperature upstream of the air flow and a high temperature downstream of the air flow. Thereby affecting heat dissipation efficiency and brightness performance.

In order to solve the above-mentioned problems, the present inventor provides a monolithic LCD projection system 1, please refer to fig. 1-5, wherein the monolithic LCD projection system 1 has a closed cavity 100, and further, the monolithic LCD projection system 1 comprises an illumination module 10, an optical module 20, a first fan 30, a second fan 40, a heat dissipation mechanism 50 and a lens 80. Wherein the lighting module 10 is configured to emit illumination light; the optical module 20 is disposed on the light-emitting side of the illumination module 10 and configured to at least convert the illumination light into imaging light, the light-emitting direction of the illumination module 10 is the same as the light-emitting direction of the optical module 20, and at least part of the optical module 20 forms a part of the closed cavity 100; the first fan 30 and the second fan 40 are arranged at intervals on one side of the optical module 20 away from the lighting module 10 and positioned in the closed cavity 100, and the first fan 30 and the second fan 40 are configured to enable gas to flow in the closed cavity 100; the heat dissipation mechanism 50 is disposed on the closed cavity 100, and at least part of the heat generated by the optical module 20 is transferred to the heat dissipation mechanism 50 by the airflow in the closed cavity 100 and is dissipated outside the closed cavity 100 by the heat dissipation mechanism 50; the lens 80 is disposed on the light-emitting side of the optical module 20, and is configured to project the image light.

In some embodiments of the present application, as shown in fig. 1 and 2, the single-panel LCD projection system 1 may be a horizontal projection system. Alternatively, in other embodiments, as shown in fig. 3 and 5, the single-panel LCD projection system 1 may be a stand-alone projection system.

Specifically, in some embodiments, referring to fig. 6, the lighting module 10 includes a light source assembly 11, a collecting lens assembly 12, and/or a collimating lens assembly 13.

The light source assembly 11 is configured to emit illumination light (working light), the illumination light is white light, the illumination light may be formed by combining RGB light, or may be formed by exciting fluorescent powder by excitation light, and in the embodiment of the present application, the illumination light is formed by exciting fluorescent powder by excitation light. In some embodiments, the light source assembly 11 may include a plurality of light emitting elements 110, the light emitting elements 110 being configured to emit excitation light, and the plurality of light emitting elements 110 may constitute a light emitting element array. In some embodiments, the Light Emitting element 110 may be an Organic Light-Emitting Diode (OLED), an inorganic Light-Emitting Diode (LED), a sub-millimeter Light-Emitting Diode (Mini LED), or a Micro Light-Emitting Diode (Micro LED), which may be selected according to practical needs. Further, the light source assembly 11 may further include a phosphor layer (not shown), which may cover the light emitting element 110, and further, the phosphor layer may be disposed on a light emitting surface of the light emitting element 110 (including a top surface and a side surface of the light emitting element 110, wherein the top surface refers to a surface of the light emitting element 110 away from the heat conducting substrate 111). The phosphor layer is configured to be excited by at least a portion of the excitation light to produce a lasing light that may be mixed with a remaining portion of the excitation light to produce illumination light. The color of the phosphor layer is related to the color of the excitation light emitted by the light emitting element 110, and is usually the complementary color, i.e. white light is generated after mixing. For example, in some embodiments, the light emitting element 110 is a blue LED chip, and the excitation light emitted by the light emitting element is blue, and then the phosphor layer is a yellow phosphor, and the yellow phosphor receives a portion of the excitation light of blue to generate yellow light, and the yellow light is mixed with a portion of the remaining blue excitation light to generate illumination light. In other embodiments, other complementary color light emitting elements 110 and phosphor layers may be used, as the application is not limited in this regard. In addition, the illumination light can be generated by combining an ultraviolet light or ultraviolet light LED chip and RGB fluorescent powder.

Further, in some embodiments, the lighting module 10 may further include a heat conductive substrate 111, the light source assembly 11 is disposed on the heat conductive substrate 111, and further, the plurality of light emitting elements 110 are disposed on the heat conductive substrate 111. The heat conducting substrate 111 is made of metal, in a specific embodiment, the heat conducting substrate 111 is an aluminum plate, and further, the heat conducting substrate 111 has a polished surface or a reflective film, and is configured to reflect light emitted from the light emitting element 110 toward the direction of the heat conducting substrate 111, so that on one hand, parasitic light in the lighting module 10 can be reduced, display effect can be improved, and meanwhile, light utilization rate can be improved; on the other hand, heat generated from the light source module 11 (including the light emitting element 110 and the phosphor layer) may also be conducted. Further, in some embodiments, the phosphor layer may cover the heat conducting substrate 111 between the adjacent light emitting elements 110 in addition to the light emitting elements 110, so that the excitation light emitted from the side surface of the light emitting element 110 may excite the phosphor layer covered on the heat conducting substrate 111, so that the illumination light provided from the light source assembly 11 is more uniform and has higher brightness.

The collecting lens assembly 12 is disposed on an outgoing light path of the light source assembly 11, specifically, on an outgoing side of the plurality of light emitting elements 110, and is configured to be capable of collecting illumination light emitted from the light source assembly 11. The collecting lens assembly 12 can collect the illumination light emitted from the light source assembly 11 in different directions as much as possible, so as to improve the utilization efficiency of the illumination light emitted from the light source assembly 11, and in some embodiments, the illumination light emitted from the light source assembly 11 can be projected to the collimating lens assembly 13 as much as possible. In some embodiments, the collecting lens assembly 12 includes a plurality of collecting lenses 120, the plurality of collecting lenses 120 are arranged in an array arrangement to form a collecting lens array 121, and the collecting lens array 121 is an integrally formed structure; the collection lens 120 may be implemented by a convex lens. The collecting lens array 121 is made of glass, silica gel or resin. In the embodiment of the present application, the material of the collecting lens array 121 is resin, so as to reduce the production cost and the process difficulty. The number of collecting lenses 120 may be the same as or different from the number of light emitting elements 110, and in order to enable the light emitted by each light emitting element 110 to be utilized, in the embodiment of the present application, the number of collecting lenses 120 may be greater than or equal to the number of light emitting elements 110, and each light emitting element 110 corresponds to one collecting lens 120. Further, in some embodiments, the number of the collecting lenses 120 is the same as the number of the light emitting elements 110, that is, the plurality of collecting lenses 120 can be arranged in one-to-one correspondence with the plurality of light emitting elements 110, so that the light emitted by the light emitting elements 110 can be utilized to the greatest extent, the waste of energy sources is avoided, the generation of astigmatism can be reduced, the display effect is improved, the generation of heat is reduced, and the light emitting device has a simple structure and low cost. The arrangement of the plurality of components in one-to-one correspondence with the plurality of components means that each component and at least part of the area of the orthographic projection of the corresponding component to the light source assembly 11 overlap, and deviation occurs between the two due to the influence of process errors, so that as long as most of the area of the orthographic projection of each component and the corresponding component to the light source assembly 11 overlap, for example, more than 50% of the area overlaps, the two can be considered to be correspondingly arranged, specifically, the area of the overlapping area can occupy 55%,60%, 65%, 70%, 75%, 80%, 85%, 90%, 95% or 100% of the area of one of the components; the "front projection" in the present application refers to a projection in a direction perpendicular to the light exit surface of the light source module 11, that is, a projection in a direction perpendicular to the surface of the light emitting element 110 away from the heat conductive substrate 111.

The collimating lens assembly 13 is disposed on the light emitting side of the light source assembly 11 and/or the light emitting sides of the plurality of collecting lenses 120, and is configured to convert the light beam with a certain divergence angle emitted by the light source assembly 11 into collimated light and/or convert the light beam with a certain divergence angle emitted by the plurality of collecting lenses 120 into collimated light, i.e. the collimating lens assembly 13 is configured to collimate the illumination light projected by the light source assembly 11 and/or the illumination light projected by the plurality of collecting lenses 120. "collimated light" as used herein refers to parallel or nearly parallel rays of light, and the output of the collimated lens assembly 13 allows as much illumination light as possible to be used. Specifically, in some embodiments, the collimating lens assembly 13 includes a plurality of collimating lenses 130, where the plurality of collimating lenses 130 are arranged in an array arrangement to form a collimating lens array 131, and the collimating lens array 131 is an integrally formed structure; the collimating lens 130 may include a convex lens, a concave lens, or a fresnel lens, or any combination thereof. The collimating lens array 131 is made of glass, silica gel or resin. In the embodiment of the present application, the collimating lens array 131 is made of resin, so as to reduce the production cost and the process difficulty. The number of the collimating lenses 130 may be the same as or different from the number of the light emitting elements 110, and in order to enable the light emitted by each light emitting element 110 to be utilized, in the embodiment of the present application, the number of the collimating lenses 130 may be greater than or equal to the number of the light emitting elements 110, and each light emitting element 110 corresponds to one collimating lens 130. Further, in some embodiments, the number of the collimating lenses 130 is the same as the number of the light emitting elements 110, that is, the plurality of collimating lenses 130 may be disposed in one-to-one correspondence with the plurality of light emitting elements 110, and further, in some embodiments, the plurality of collimating lenses 130, the plurality of collecting lenses 120 and the plurality of light emitting elements 110 may be disposed in one-to-one correspondence, in this way, when the optical module 20 is increased, the length and width of the lighting module 10 need only be increased accordingly, without increasing the distance from the optical module 20 at the same time, so that a small volume and high brightness can be achieved.

Further, the principle of the lighting module 10 of the present application for achieving uniform lighting is: the light emitted by the single light emitting element 110 and the corresponding phosphor layer is collimated by the collimating lens 130 and then has a certain divergence angle, and adjacent small light spots are overlapped on a surface with a certain distance from the collimating lens 130, and the overlapped small light spots form a large area light spot with uniform illumination. Specifically, referring to fig. 6 to 10, fig. 6 shows a light path diagram of illumination light emitted from 3 light emitting elements 110 and corresponding phosphor layers (not shown), fig. 7 shows a light spot distribution of illumination light emitted from a single light emitting element 110 and corresponding phosphor layer (not shown) on a illuminated surface, fig. 8 shows a state after overlapping illumination light emitted from a plurality of light emitting elements 110 and corresponding phosphor layers (not shown), fig. 9 shows an initial state when overlapping 3 light spots, and fig. 10 shows a final state when overlapping 3 light spots. Wherein, the distance between the light source assembly 11 and the collimator lens assembly 13 is related to the arrangement density (filling rate) of the plurality of collimator lenses 130, and the more sparsely the plurality of collimator lenses 130 are arranged, the more distant is required.

Therefore, in order to achieve a compact arrangement with a certain volume and a maximum efficiency in consideration of the efficiency and the filling rate of the plurality of collimating lenses 130 and the volume of the monolithic LCD projection system 1, in some embodiments of the present application, referring to fig. 11, fig. 11 is a top view of the collimating lens assembly 13, the collecting lens assembly 12 and the light source assembly 11 in the monolithic LCD projection system 1 according to some embodiments of the present application, the collimating lenses 130 are designed to be regular hexagons, and the edges of adjacent collimating lenses 130 are abutted and closely arranged, i.e. the plurality of collimating lenses 130 are seamlessly spliced, so that a seamless collimating lens array 131 can be formed. Further, the plurality of light emitting elements 110 and the collimator lens assembly 13 are arranged in a rectangular shape matching the size of the optical module 20, respectively. Alternatively, the shape of the collecting lens 120 may be circular or hexagonal, and in particular, may be set as needed. In the embodiment of the present application, the shape of the collecting lens 120 is a circle. Alternatively, in other embodiments, the shape of the collection lens 120 may be designed as a regular hexagon, with the sides of adjacent collection lenses 120 abutting and closely spaced, i.e., multiple collection lenses 120 seamlessly joined together, so that a seamless collection lens array 121 may be formed. In the present application, the shape of the collimator lens 130 refers to the shape of the front projection of the collimator lens 130 onto the light source module 11, and the shape of the collecting lens 120 also refers to the shape of the front projection of the collecting lens 120 onto the light source module 11.

Alternatively, in order to enhance the light utilization of the light source assembly 11, in other embodiments, the collimating lens 130 of the outermost circle of the array of collimating lenses 130 may not be cut into a hexagon. Specifically, referring to fig. 12, the collimating lens 130 array includes a first main body portion 132 and a first peripheral portion 133, the first main body portion 132 includes a plurality of first sub-collimating lenses 1320, and the first peripheral portion 133 includes a plurality of second sub-collimating lenses 1330; a plurality of second sub-collimator lenses 1330 are disposed around the plurality of first sub-collimator lenses 1320; the plurality of first sub-collimator lenses 1320 have a regular hexagon shape, and the plurality of second sub-collimator lenses 1330 are arranged closely to the first sub-collimator lenses 1320, i.e. the shape of the side of the second sub-collimator lenses 1330 close to the first sub-collimator lenses 1320 is a part of the regular hexagon, the shape of the side of the second sub-collimator lenses 1330 away from the first sub-collimator lenses 1320 is an arc shape, further, the second sub-collimator lenses 1330 correspond to a circumcircle, and the arc shape is located on the circumcircle. Alternatively, the shape of the collection lens 120 may be designed as desired, such as circular or hexagonal. In the embodiment of the present application, the plurality of collecting lenses 120 are all circular in shape. Alternatively, in other embodiments, the collection lens array 121 includes a second body portion including a plurality of first sub-collection lenses and a second peripheral portion including a plurality of second sub-collection lenses; the plurality of second sub-collecting lenses are arranged around the plurality of first sub-collecting lenses; the shape of a plurality of first sub-collecting lenses is regular hexagon, and a plurality of second sub-collecting lenses are closely arranged with the first sub-collecting lenses, namely, the shape of one side of the second sub-collecting lenses close to the first sub-collecting lenses is a part of the regular hexagon, the shape of one side of the second sub-collecting lenses far away from the first sub-collecting lenses is arc-shaped, further, the second sub-collecting lenses correspond to an external circle, and the arc-shaped is positioned on the external circle.

Further, considering that the aberration of the peripheral portion of the light source assembly 11 after converging through the collecting lens 120 becomes large, the etendue of the edge area portion of the array of light emitting elements 110 may be set smaller than that of the central area portion, and the lens may be matched with the etendue of the illumination light to improve the overall efficiency. Further, the second focal length of the plurality of second sub-collimator lenses 1330 is greater than the first focal length of the plurality of first sub-collimator lenses 1320. Optionally, the fourth focal length of the plurality of second collection lenses 120 is greater than the third focal length of the plurality of first collection lenses 120. The ratio of the area of the front projection of the "central region" to the light source assembly 11 to the area of the largest front projection of the light source assembly 11 is greater than or equal to 60% and less than 100%; further, in some embodiments, the area of the forward projection of the central region to the light source assembly 11 is greater than or equal to 80% and less than 100% of the area of the maximum forward projection of the light source assembly 11; still further, in some embodiments, the area of the forward projection of the central region to the light source assembly 11 is greater than or equal to 90% and less than 100% of the area of the maximum forward projection of the light source assembly 11.

The optical module 20 is disposed on the light emitting side of the illumination module 10 and configured to convert at least illumination light into image light, and the light emitting direction of the optical module 20 may be the same as the light emitting direction of the illumination module 10, and it should be noted that, in the present application, the light emitting direction of the component (e.g., the optical module 20, the illumination module 10) refers to the main light emitting direction of the component, and the main light emitting direction is perpendicular to the largest surface of the component. By means of the mode, on one hand, the light emitting surface of the optical module 20 and the light emitting surface of the illumination module 10 can be arranged in parallel and at intervals along the same direction, illumination light emitted by the optical module 20 can be directly projected to the optical module 20, the light utilization rate is improved, the use of other components is reduced, on the other hand, the single-chip LCD projection system 1 is compact in structure, convenient to design and adjust, simpler in structure and cost-saving. In some embodiments, referring to fig. 1-5, at least a portion of the optical module 20 forms a part of the closed cavity 100, so as to achieve a simple structure and reduce the optical loss caused by the increase of interfaces with different refractive indexes. Specifically, the optical module 20 includes a first optical element 21, a second optical element 22, and a third optical element 23. Wherein the first optical element 21 is disposed on the light emitting side of the lighting module 10; the second optical element 22 is arranged at a distance from one side of the first optical element 21 away from the lighting module 10; the third optical element 23 is disposed at a distance from the side of the second optical element 22 away from the first optical element 21; the first optical element 21 and the third optical element 23 respectively form part of the closed cavity 100, i.e. the first optical element 21 and the third optical element 23 participate in forming the closed cavity 100.

In some embodiments, the lighting module 10 is configured to emit collimated illumination light and provide telecentric illumination. Specifically, in some embodiments, the first optical element 21 includes glass, and a brightness enhancement film and a first absorption-type polarizing film disposed on a surface of the glass remote from the second optical element 22, the first absorption-type polarizing film configured to transmit polarized light of a first polarization direction; the second optical element 22 includes a liquid crystal panel and a second absorption-type polarizing film disposed on a surface of the liquid crystal panel remote from the first optical element 21, and the liquid crystal panel may include an incident-side substrate and an exit-side substrate disposed at a distance from each other and a liquid crystal layer disposed between the incident-side substrate and the exit-side substrate; the second absorption-type polarizing film is configured to transmit polarized light of a second polarization direction; the first absorption type polarizing film and the absorption type polarizing film are orthogonal, namely unpolarized light passes through the first absorption type polarizing film to form first polarized light, unpolarized light passes through the second absorption type polarizing film to form second polarized light, and the polarization direction of the first polarized light is perpendicular to that of the second polarized light; the third optical element 23 comprises a fresnel lens.

Optionally, in other embodiments, the lighting module 10 is configured to emit collimated illumination light and provide non-telecentric illumination. Specifically, the first optical element 21 includes a fresnel lens and a first absorption-type polarizing film provided on a surface of the fresnel lens near the second optical element 22; the second optical element 22 includes a liquid crystal panel; the third optical element 23 includes glass and a second absorption-type polarizing film provided on a surface of the glass remote from the third optical element 23, the first absorption-type polarizing film being orthogonal to the second absorption-type polarizing film.

The inventors of the present application have further studied and found that, although the heat dissipation capability of the single-chip LCD projection system 1 can be improved by disposing the first optical element 21, the second optical element 22 and the third optical element 23 at intervals, the separated first optical element 21, second optical element 22 and third optical element 23 generate a plurality of interfaces with air, and light loss is caused when light passes through interfaces having different refractive indexes at both sides.

In order to solve the above-mentioned technical problem, in some embodiments of the present application, referring to fig. 13, a dielectric film 24 is disposed on at least one surface of the first optical element 21, the second optical element 22 and the third optical element 23 that are disposed at intervals. The dielectric film 24 has a multi-layer structure formed of materials with different refractive indexes, such as an Anti-Reflection (AR) film. In some embodiments, the dielectric film 24 is a graded index dielectric film 24, where graded index dielectric film 24 refers to a film having a refractive index that varies gradually along the thickness direction (normal direction) of the film layer, but remains unchanged in the thickness direction (normal direction) perpendicular to the film layer.

After the second optical element 22 is designed separately from the first optical element 21 and/or the second optical element 22 and the third optical element 23, a plurality of interfaces with air are created. It will be appreciated that when light passes through an interface of two different refractive indices, some of the light is transmitted and used and some of the light is reflected causing light loss. Thus, the dielectric films 24 are disposed on the surfaces at intervals to increase the transmittance of light, and the specific principle is as follows.

From the fresnel formula, it can be obtained:

wherein ε ₁ For epsilon ₂ Where θ is θ ".

From the fresnel formula, it is possible to obtain:

wherein n is ₁ Is n ₂ Is the following.

Thus, the first and second substrates are bonded together,

if light is directly incident perpendicularly on glass (air-glass) from air, it

If n layers of equal-step-length refractive index gradient media are placed between air and glass, the transmittance and gradient layer number n curve is shown in fig. 14, so that the transmittance is higher as the number of layers of the dielectric film 24 is larger. However, instead of increasing the number of layers, it is preferable that the transmittance is substantially reduced when the number of layers is increased by a certain amount, as shown in fig. 14, and the excessive number of layers of the dielectric film 24 not only increases the cost, but also occupies more internal space to be unfavorable for heat dissipation, so that in some embodiments of the present application, the thickness of the dielectric film 24 is less than 5 μm.

According to the application, the first optical element 21 and the second optical element 22 are arranged at intervals and/or the second optical element 22 and the third optical element 23 are arranged at intervals, so that the temperature interaction among the first optical element 21, the second optical element 22 and the third optical element 23 is reduced, and gaps are formed between adjacent elements arranged at intervals, so that a space is created for air flow, and the heat dissipation efficiency is further improved; the dielectric films 24 on the surfaces of the spaced elements may reduce light loss, and in some embodiments, may increase the transmittance by more than 6% and reduce heat generation.

In some embodiments, the first fan 30 and the second fan 40 may be centrifugal fans. The air flow within the enclosed cavity 100 may flow clockwise or counter-clockwise depending on the location of the air outlets and inlets of the first and second fans 30 and 40. Specifically, in some embodiments, the first fan 30 has a first air inlet 31 and a first air outlet 32, and the second fan 40 has a second air inlet 41 and a second air outlet 42. The first air inlet 31 is configured to absorb the air flow flowing through the opposite surfaces of the first optical element 21 and the second optical element 22, and the first air outlet 32 is configured to accelerate the air flow to be discharged and to flow the air flow through the opposite surfaces of the second optical element 22 and the third optical element 23; the second air intake 41 is configured to absorb the air flow flowing through the opposite surfaces of the second optical element 22 and the third optical element 23, and the second air intake 41 is configured to accelerate the air flow to be discharged and flow the air flow through the opposite surfaces of the second optical element 22 and the third optical element 23. The first fan 30 is configured to suck the air flow flowing through the opposite surfaces of the first optical element 21 and the second optical element 22 into the first fan 30, accelerate the air flow and discharge the air flow, and the air flow passes through the opposite surfaces of the second optical element 22 and the third optical element 23, thereby cooling the second optical element 22 and the third optical element 23. The second fan 40 is configured to suck the air flowing through the opposite surfaces of the second optical element 22 and the third optical element 23 into the second fan 40, accelerate the air and discharge the air, and the air passes through the opposite surfaces of the first optical element 21 and the second optical element 22, thereby cooling the first optical element 21 and the second optical element 22. The directions of the air flows on the light-emitting surface and the light-entering surface of the second optical element 22 are opposite, so that the problem that the heat dissipation uniformity and the heat dissipation efficiency are improved due to the fact that the temperature is uneven caused by the fact that the air flows on the light-emitting surface and the light-entering surface of the second optical element 22 are in the same direction, the trend that the upstream temperature of the air flow is low and the downstream temperature of the air flow is high is solved, and further the heat dissipation efficiency and the brightness performance are affected is solved. After the heat dissipation effect is improved, a stronger backlight source can be adopted, so that the brightness of the projector can be improved.

Further, the heat dissipation mechanism 50 includes a first heat dissipation mechanism 51 and a second heat dissipation mechanism 52. The first heat dissipation mechanism 51 and the second heat dissipation mechanism 52 are respectively arranged at two opposite sides of the optical module 20 along the direction perpendicular to the light emitting direction of the illumination module 10, wherein the front projection of the first heat dissipation mechanism 51 along the direction perpendicular to the light emitting direction of the illumination module 10 covers the optical module 20 and the first fan 30; and/or the second heat dissipation mechanism 52 covers the optical module 20 along the orthographic projection perpendicular to the light emitting direction of the lighting module 10, that is, along the light emitting direction of the optical module, the length of the first heat dissipation mechanism 51 is greater than the sum of the lengths of the optical module 20 and the first fan 30; and/or the length of the second heat dissipation mechanism 52 is greater than the length of the optical module 20. Because the length of the first heat dissipation mechanism 51 is greater than the sum of the lengths of the optical module 20 and the first fan 30, the first heat dissipation mechanism 51 can cover the whole optical module 20 and the first fan 30, so that the heat dissipation area can be enlarged, and the heat dissipation effect can be improved; the length of the second heat dissipation mechanism 52 is greater than that of the optical module 20, so that the second heat dissipation mechanism 52 can cover the whole optical module 20, further improving the heat dissipation effect of the optical module 20 and saving the cost; by providing the first heat dissipation mechanism 51 and the second heat dissipation mechanism 52 on opposite sides of the optical module 20, the heat exchange efficiency between the first heat dissipation mechanism 51 and the second heat dissipation mechanism 52 and the air outside the closed cavity 100 can be made higher, so that the heat dissipation efficiency of the optical module 20 can be improved.

The first heat dissipation mechanism 51 and the second heat dissipation mechanism 52 are configured to dissipate heat from the optical module, the first heat dissipation mechanism 51 and the second heat dissipation mechanism 52 being good conductors of heat, such as metals including silver, copper, aluminum. In the present application, the first heat dissipation mechanism 51 and the second heat dissipation mechanism 52 are made of aluminum. In some embodiments, the first heat dissipation mechanism 51 and/or the second heat dissipation mechanism 52 are/is aluminum sheets, at least part of the heat generated by the optical module 20 is transferred to the first heat dissipation mechanism 51 and the second heat dissipation mechanism 52 through the air flow in the closed cavity 100, and at least part of the heat generated by the optical module 20 is simultaneously transferred to the first heat dissipation mechanism 51 and the second heat dissipation mechanism 52 through the closed cavity, and is dissipated outside the closed cavity 100 through the first heat dissipation mechanism 51 and the second heat dissipation mechanism 52. Specifically, the first heat dissipation mechanism 51 and the second heat dissipation mechanism 52 may absorb waste heat of the closed cavity 100 and dissipate the waste heat to the outside of the closed cavity 100. In some embodiments, the monolithic LCD projection system 1 may further have an external circulation air duct 200, where the external circulation air duct 200 is located outside the closed cavity 100, and the first heat dissipation mechanism 51 and the second heat dissipation mechanism 52 may absorb waste heat of the closed cavity 100 by isolating the side wall of the closed cavity 100 from the air flow located in the closed cavity 100, and dissipate the waste heat into the external circulation air duct 200 outside the closed cavity 100, so as to implement cooling of the optical module. In other embodiments, the first heat dissipation mechanism 51 may include a plurality of heat dissipation fins disposed at intervals, and the arrangement direction of the plurality of heat dissipation fins may be the same as the arrangement direction of the first optical element 21, the second optical element 22, and the third optical element 23. The plurality of radiating fins arranged at intervals can exchange heat with the air flow in the closed cavity.

Specifically, in some embodiments, the monolithic LCD projection system 1 further includes a connection mechanism 60, the connection mechanism 60 forming a portion of the enclosed cavity 100, at least a portion of the connection mechanism 60 being connected with the first optical element 21, the second optical element 22, and the third optical element 23 to form the enclosed cavity 100.

Specifically, in some embodiments, the connection mechanism 60 includes a first connection mechanism 61, a second connection mechanism 62, a third connection mechanism 63, and a fourth connection mechanism 64. The opposite ends of the first connecting mechanism 61 are respectively connected to the first end of the third optical element 23 and the first end of the first optical element 21, and the first connecting mechanism 61 and the first end of the second optical element 22 are disposed at intervals, in some embodiments, the first connecting mechanism 61 may be a bent structure, further, in some embodiments, the first connecting mechanism 61 may be an integral structure or may be formed by splicing a plurality of split structures, and the first heat dissipation mechanism 51 is disposed on an outer surface of at least part of the first connecting mechanism 61. Opposite ends of the second connection mechanism 62 are respectively connected to the first end of the second optical element 22 and the first fan 30 or the mounting structure near the first fan 30, the second connection mechanism 62 is spaced from the first end of the third optical element 23, and the second connection mechanism 62 may have a plate-like structure. Opposite ends of the third connecting mechanism 63 are respectively connected to the second end of the first optical element 21 and the second end of the third optical element 23, and the third connecting mechanism 63 is disposed between the second end of the second optical element 22 and the second end of the third connecting mechanism 63. The second connection 62, the fourth connection 64, and the second optical element 22 may divide the enclosed cavity into a first chamber and a second chamber, the first blower being located in the first chamber and the second blower being located in the second chamber.

The materials of the first connecting mechanism 61, the second connecting mechanism 62, the third connecting mechanism 63, and the fourth connecting mechanism 64 are not limited, and may be selected as needed. In some embodiments, the first connection mechanism 61, the second connection mechanism 62, the third connection mechanism 63, and the fourth connection mechanism 64 are plastic; alternatively, in other embodiments, the first connecting mechanism 61, the second connecting mechanism 62, the third connecting mechanism 63, and the fourth connecting mechanism 64 are heat conducting mechanisms with heat conducting function, such as metal substrates, for better heat dissipation.

Optionally, in some embodiments, the monolithic LCD projection system 1 further includes a housing 70 defining a receiving space 71, and the lighting module 10, the optical module 20, the first fan 30, the second fan 40, the first heat dissipation mechanism 51, and the second heat dissipation mechanism 52 are disposed in the receiving space 71.

Optionally, in some embodiments, the monolithic LCD projection system 1 further includes an illumination heat dissipation mechanism 90 and a third fan (not shown), wherein the illumination heat dissipation mechanism 90 is connected to the thermally conductive substrate 111 and configured to dissipate heat from the light source assembly 11. In some embodiments, the heat dissipation mechanism 50 and the illumination heat dissipation mechanism 90 are at least partially positioned on the same line along the light emitting direction of the illumination module 10; the third fan is configured to cool at least part of the heat dissipation mechanism 50 and at least part of the illumination heat dissipation mechanism 90, and the illumination module and the optical module can dissipate heat at the same time by using the same fan, so that the structure is simple and the efficiency is high. The third fan and the first fan 30 and the second fan 40 can radiate heat to the inside and the outside of the lighting module 10 and the optical module 20 at the same time, thereby improving the heat radiation effect. Further, in some embodiments, the illumination heat dissipation mechanism 90 includes a third heat dissipation mechanism 91 and a fourth heat dissipation mechanism 92, and the third heat dissipation mechanism 91 and the fourth heat dissipation mechanism 92 are respectively disposed on two opposite sides of the optical module 20 along the light emitting direction of the illumination module. The third heat dissipation mechanism 91 and the fourth heat dissipation mechanism 92 are connected to the heat conduction substrate 111 and configured to conduct heat of the light source assembly 11, and in this way, a heat dissipation area can be increased, and a heat dissipation effect can be improved. Still further, the front projection of the third heat dissipation mechanism 91 along the direction perpendicular to the light emitting direction of the lighting module 10 covers the lighting module 10, the front projection of the fourth heat dissipation mechanism 92 along the direction perpendicular to the light emitting direction of the lighting module 10 covers the lighting module 10, i.e. along the light emitting direction of the lighting module, the length of the third heat dissipation mechanism 91 is greater than the length of the light source assembly 11, and the length of the fourth heat dissipation mechanism 92 is greater than the length of the light source assembly 11. Still further, in some embodiments, the monolithic LCD projection system further includes a fourth fan (not shown), and along the light emitting direction of the lighting module 10, the first heat dissipation mechanism 51 and the third heat dissipation mechanism 91 are at least partially located on the same line, and the second heat dissipation mechanism 52 and the fourth heat dissipation mechanism 92 are at least partially located on the same line; the third fan is configured to cool at least part of the first heat dissipation mechanism 51 and the third heat dissipation mechanism 91; the fourth fan is configured to cool the second heat dissipation mechanism 52 and the fourth heat dissipation mechanism 92. So, can dispel the heat through two fans respectively, illuminating module and optical module simultaneously in both sides, radiating efficiency is high, and simple structure, and can fully dispel the heat. In a preferred embodiment, the first heat dissipation mechanism 51 and the third heat dissipation mechanism 91 are disposed in contact, the second heat dissipation mechanism 52 and the fourth heat dissipation mechanism 92 may be disposed in contact, and heat may be directly transferred between the heat dissipation mechanisms, thereby improving heat transfer efficiency and further improving heat dissipation efficiency.

The heat dissipation process of the monolithic LCD projection system 1 provided by the application is as follows: after the air is accelerated by the first fan 30, the air flows through two opposite surfaces of the second optical element 22 and the third optical element 23, namely, through the light-emitting surface of the second optical element 22 and the light-entering surface of the third optical element 23, and dissipates heat for the air, and the air flow immediately enters the second fan 40; after the airflow is accelerated by the second fan 40, the heat of the airflow is partially transferred to the second heat dissipation mechanism 52 through the second heat dissipation mechanism 52, the second heat dissipation mechanism 52 dissipates the heat to the outside of the closed cavity, and then flows through the opposite surfaces of the first optical element 21 and the second optical element 22, namely, the light-emitting surface of the first optical element 21 and the light-entering surface of the second optical element 22, the heat of the first optical element 21 and the second optical element 22 is transferred to the airflow, and then the airflow passes through the first heat dissipation mechanism 51, in the process, the heat of the airflow is transferred to the first heat dissipation mechanism 51, the first heat dissipation mechanism 51 dissipates the heat to the outside of the closed cavity, and the airflow enters the first fan 30 again to complete a heat dissipation cycle. In this process, the air flow in the external circulation air duct 200 exchanges heat with the first heat dissipation mechanism 51 and the second heat dissipation mechanism 52, so as to achieve the effect of dissipating heat from the air flow and/or the components in the closed cavity 100. In addition to the above-mentioned heat exchange process by gas, the heat of the optical module may be transferred to the first heat dissipation mechanism 51 and the second heat dissipation mechanism 52 through the closed housing to dissipate the heat.

Optionally, in some embodiments, in order to reduce the length of the single-chip LCD projection system 1, please refer to fig. 3-5, the single-chip LCD projection system 1 may further include a reflective element 81, wherein the reflective element 81 may be disposed between the illumination module 10 and the collimator lens assembly 13 to turn the light path by 90 °, the reflective element 81 may also be disposed between the optical module 20 and the lens 80 to turn the light path by 90 °, or the single-chip LCD projection system 1 may include two reflective elements 81 disposed between the illumination module 10 and the collimator lens assembly 13 and between the optical module 20 and the lens 80, respectively.

The closed cavity 100 in the present application may be a closed air duct, and by such a design, the influence of the outside (such as dust or water vapor) on the optical module 20 can be reduced, and the noise can be greatly reduced.

It will be appreciated that the above embodiment of the present application provides a single-chip LCD projection system 1 that may further include other optical elements known in the art, such as a light homogenizing element, fly's eye lens, etc., and may be specifically designed according to the need, which is not specifically limited by the present application.

The above-mentioned embodiment does not limit the monolithic LCD projection system to include all the components mentioned in the examples, nor limit all the components to be disposed adjacent to or in direct contact with each other, and in practical application, suitable components, or relative positional relationships, may be selected according to requirements such as product structures, or other structures may be disposed between adjacent components to allow the adjacent components to be in indirect contact with each other.

The foregoing is only the embodiments of the present application, and therefore, the patent scope of the application is not limited thereto, and all equivalent structures or equivalent processes using the descriptions of the present application and the accompanying drawings, or direct or indirect application in other related technical fields, are included in the scope of the application.

Claims (16)

1. A monolithic LCD projection system having a closed cavity, said monolithic LCD projection system comprising:

an illumination module configured to emit illumination light;

an optical module, disposed on the light-emitting side of the illumination module, configured to convert at least the illumination light into imaging light; the light-emitting direction of the illumination module is the same as the light-emitting direction of the optical module; at least part of the optical module forms part of the closed cavity;

the first fan and the second fan are arranged at intervals on one side of the optical module, which is far away from the lighting module, and are positioned in the closed cavity; the first blower and the second blower are each configured to flow gas within the enclosed cavity;

the heat dissipation mechanism is arranged on the closed cavity;

At least part of heat generated by the optical module is transferred to the heat dissipation mechanism through the air flow in the closed cavity and is dissipated outside the closed cavity through the heat dissipation mechanism.

2. The monolithic LCD projection system of claim 1 wherein the optical module comprises:

the first optical element is arranged on one side of the lighting module and is formed into a part of the closed cavity;

the second optical elements are arranged at one side of the first optical element away from the lighting module at intervals;

and the third optical element is arranged at one side of the second optical element away from the first optical element at intervals and is formed as a part of the closed cavity.

3. The single-panel LCD projection system of claim 2, further comprising at least one dielectric film; wherein at least one surface of at least one of the first optical element, the second optical element, and the third optical element is provided with the dielectric film; the dielectric film has a multi-layer structure formed by materials with different refractive indexes.

4. The single-chip LCD projection system of claim 3, wherein the heat dissipation mechanism comprises a first heat dissipation mechanism and a second heat dissipation mechanism, and the first heat dissipation mechanism and the second heat dissipation mechanism are respectively disposed on two opposite sides of the optical module along a direction perpendicular to the light emitting direction of the illumination module.

5. The single-chip LCD projection system according to claim 4, wherein the length of the first heat dissipation mechanism is greater than the sum of the lengths of the optical module and the first fan along the light-emitting direction of the optical module; and/or the length of the second heat dissipation mechanism is greater than the length of the optical module.

6. The monolithic LCD projection system of claim 2 wherein the first optical element comprises a glass and a brightness enhancing film and a first absorptive polarizing film disposed on a surface of the glass remote from the second optical element; the second optical element comprises a liquid crystal panel and a second absorption type polarizing film arranged on the surface of the liquid crystal panel far away from the first optical element, and the first absorption type polarizing film and the second absorption type polarizing film are orthogonal; the third optical element includes a fresnel lens.

7. The monolithic LCD projection system of claim 2 wherein the first optical element comprises a fresnel lens and a first absorptive polarizing film disposed on a surface of the fresnel lens proximate the second optical element; the second optical element includes a liquid crystal panel; the second optical element includes a glass and a second absorbing polarizing film disposed on a surface of the glass remote from the third optical element, the first absorbing polarizing film being orthogonal to the second absorbing polarizing film.

8. The monolithic LCD projection system of any of claims 4-5, further comprising an illumination heat dissipation mechanism;

the lighting module comprises a light source assembly and a heat conducting substrate, wherein the light source assembly is arranged on the heat conducting substrate and is configured to emit the lighting light, the light source assembly comprises a plurality of light emitting elements, the lighting heat dissipation mechanism is connected with the heat conducting substrate and is configured to dissipate heat of the light source assembly.

9. The single-chip LCD projection system according to claim 8, wherein the heat dissipation mechanism and the illumination heat dissipation mechanism are at least partially positioned on the same straight line along the light emitting direction of the illumination module; the monolithic LCD projection system further includes a third fan configured to dissipate heat from at least a portion of the heat dissipation mechanism and at least a portion of the illumination heat dissipation mechanism.

10. The single-chip LCD projection system according to claim 9, wherein the illumination heat dissipation mechanism comprises a third heat dissipation mechanism and a fourth heat dissipation mechanism, and the third heat dissipation mechanism and the fourth heat dissipation mechanism are respectively disposed at two opposite sides of the illumination module along the light emitting direction of the illumination module; in the light emitting direction of the lighting module, the length of the third heat dissipation mechanism is longer than that of the light source assembly, and the length of the fourth heat dissipation mechanism is longer than that of the light source assembly.

11. The monolithic LCD projection system of claim 10, further comprising a fourth fan;

along the light emitting direction of the lighting module, the first heat dissipation mechanism and the third heat dissipation mechanism are at least partially positioned on the same straight line, and the second heat dissipation mechanism and the fourth heat dissipation mechanism are at least partially positioned on the same straight line; the third fan is configured to cool at least part of the first heat dissipation mechanism and the third heat dissipation mechanism; the monolithic LCD projection system further includes a fourth fan configured to cool the second and fourth heat dissipation mechanisms.

12. The monolithic LCD projection system of claim 11 wherein the light source assembly further comprises a phosphor layer covering the plurality of light emitting elements or the phosphor layer covering the plurality of light emitting elements and a thermally conductive substrate between adjacent light emitting elements, the light emitting elements configured to emit excitation light, the phosphor layer configured to generate lasing light upon excitation by at least a portion of the excitation light.

13. The single-panel LCD projection system of claim 12, wherein the illumination module comprises:

a plurality of collecting lenses provided on the light emitting sides of the plurality of light emitting elements, configured to collect the illumination light emitted from the light source assembly;

a plurality of collimating lenses disposed on the light-emitting side of the plurality of collecting lenses, configured to collimate the illumination light projected by the plurality of collecting lenses;

the collimating lenses, the collecting lenses and the light-emitting elements are arranged in a one-to-one correspondence.

14. The single-piece LCD projection system of claim 13, wherein the plurality of collimating lenses form a collimating lens array, the collimating lenses having a regular hexagonal shape, and edges of adjacent collimating lenses abutting and being closely spaced.

15. The monolithic LCD projection system of claim 13 wherein the plurality of collimating lenses comprise a collimating lens array; the collimating lens array comprises a first main body part and a first peripheral part, wherein the first main body part comprises a plurality of first sub-collimating lenses, and the first peripheral part comprises a plurality of second sub-collimating lenses; the plurality of second sub-collimator lenses are disposed around the plurality of first sub-collimator lenses; the shape of a plurality of first sub-collimating lenses is regular hexagon, adjacent sides of the first sub-collimating lenses are abutted and closely spread, a plurality of second sub-collimating lenses are closely spread with a plurality of first sub-collimating lenses, and the shape of one side of the second sub-collimating lenses far away from the first sub-collimating lenses is circular.

16. The single-chip LCD projection system according to claim 14 or 15, wherein the second focal length of the plurality of second sub-collimator lenses is greater than the first focal length of the plurality of first sub-collimator lenses.