CN116626932A - Display module and projector - Google Patents

Display module and projector Download PDF

Info

Publication number
CN116626932A
CN116626932A CN202310593740.XA CN202310593740A CN116626932A CN 116626932 A CN116626932 A CN 116626932A CN 202310593740 A CN202310593740 A CN 202310593740A CN 116626932 A CN116626932 A CN 116626932A
Authority
CN
China
Prior art keywords
light
display module
guide plate
light source
splitting
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202310593740.XA
Other languages
Chinese (zh)
Inventor
谭祺瑞
张伟
李熙
刘小龙
王甲强
董大林
王宇杰
杨昱
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BOE Technology Group Co Ltd
Beijing BOE Display Technology Co Ltd
Beijing BOE Technology Development Co Ltd
Original Assignee
BOE Technology Group Co Ltd
Beijing BOE Display Technology Co Ltd
Beijing BOE Technology Development Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by BOE Technology Group Co Ltd, Beijing BOE Display Technology Co Ltd, Beijing BOE Technology Development Co Ltd filed Critical BOE Technology Group Co Ltd
Priority to CN202310593740.XA priority Critical patent/CN116626932A/en
Publication of CN116626932A publication Critical patent/CN116626932A/en
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133602—Direct backlight
    • G02F1/133606—Direct backlight including a specially adapted diffusing, scattering or light controlling members
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0033—Means for improving the coupling-out of light from the light guide
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133602—Direct backlight
    • G02F1/133606—Direct backlight including a specially adapted diffusing, scattering or light controlling members
    • G02F1/133607—Direct backlight including a specially adapted diffusing, scattering or light controlling members the light controlling member including light directing or refracting elements, e.g. prisms or lenses
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/005—Projectors using an electronic spatial light modulator but not peculiar thereto
    • G03B21/006—Projectors using an electronic spatial light modulator but not peculiar thereto using LCD's
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/14—Details
    • G03B21/142—Adjusting of projection optics
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B21/00—Projectors or projection-type viewers; Accessories therefor
    • G03B21/14—Details
    • G03B21/20—Lamp housings

Abstract

The utility model relates to a display module assembly, this display module assembly includes light source and light guide plate, and the incident light of light source gets into the light guide plate, and the light guide plate includes the light-emitting part, and the light-emitting part includes a plurality of first beam splitting faces that set up along first direction, and incident light is through first beam splitting face reflection and transmission, forms first reflection light and follows the second direction outgoing, and the second direction is perpendicular to the face of light guide plate. The luminous points of the light source are dispersed into a plurality of sub luminous points through the plurality of first light splitting surfaces, so that the central brightness and the edge brightness of the backlight of the liquid crystal display panel are consistent, the difference of different areas of the display picture is small, and the uniformity of the projection picture is good. The disclosure also provides a projector comprising the display module.

Description

Display module and projector
Technical Field
The disclosure relates to the technical field of display, in particular to a display module and a projector.
Background
The projector comprises a light source and a liquid crystal display panel, wherein light rays emitted by the light source are irradiated to the liquid crystal display panel for imaging and then projected onto a curtain to form a projection picture for displaying.
The light intensity distribution of the light source meets the lambertian distribution, the brightness of the center of the backlight is higher, the edge brightness is poorer, the difference between different areas of a display picture is larger, and finally the uniformity of a projection picture is poorer.
It should be noted that the information disclosed in the above background section is only for enhancing understanding of the background of the present disclosure and thus may include information that does not constitute prior art known to those of ordinary skill in the art.
Disclosure of Invention
The disclosure aims to solve the problem of poor uniformity of an existing projection picture, and provides a display module and a projector.
According to one aspect of the present disclosure, there is provided a display module, including a light source, a light guide plate and a liquid crystal display panel, the light guide plate including a light emitting portion including a plurality of first light splitting surfaces arranged along a first direction, first reflected light of the first light splitting surfaces exiting along a second direction, the second direction being perpendicular to a plate surface of the light guide plate, the first direction being perpendicular to the second direction; the liquid crystal display panel is arranged on one side of the light guide plate far away from the light source.
In one embodiment of the disclosure, the light emitting portion includes a first prism group disposed along a first direction, the first prism group includes two first right-angle triangular prisms, a plurality of first parallelogram prisms are disposed between the two first right-angle triangular prisms, the first light splitting surface is an inclined surface of the first right-angle triangular prism, and a surface of the first parallelogram prism parallel to the inclined surface of the first right-angle triangular prism.
In one embodiment of the disclosure, the light guide plate further includes a light incident portion, the light incident portion includes at least a plurality of second light splitting surfaces, the second light splitting surfaces are located on incident light rays of the light source, the first light splitting surfaces are located on second reflected light rays of the second light splitting surfaces, the incident light rays of the light source extend along a third direction, and the third direction is perpendicular to the first direction and the second direction.
In one embodiment of the disclosure, the light incident portion includes a second prism group disposed along a third direction, the second prism group includes two second right angle triangular prisms, a plurality of second parallelogram prisms are disposed between the two second right angle triangular prisms, the second light splitting surface is an inclined surface of the second right angle triangular prism, and a surface of the second parallelogram prism parallel to the inclined surface of the second right angle triangular prism, and the third direction is perpendicular to the first direction and the second direction.
In one embodiment of the present disclosure, the energy of the n-th second reflected light formed by splitting the incident light of the light source through the n-th second splitting surface in the second prism group is:
A n ＝A 0 ×(1-K 1 )×(1-K 2 )×…×(1-K n-1 )×K n ；
wherein K1...Kn is the reflectance of the 1 st to n th second light splitting surfaces, A0 is the energy of the incident light of the light source, and An is the energy of the n th second reflected light.
In one embodiment of the present disclosure, a light source includes a planar light emitter and a planar convex lens, a plane of the planar convex lens disposed proximate a light emitting side of the planar light emitter.
In one embodiment of the present disclosure, a dimension of the light source along the first direction is equal to a dimension of the light incident portion along the first direction.
In one embodiment of the present disclosure, the front projection of the liquid crystal display panel on the light guide plate overlaps the light emitting portion.
In one embodiment of the present disclosure, the first light splitting surface is located on a transmission light of the second light splitting surface, the second light splitting surface is located on an incident light of the light source, and the incident light of the light source extends along the first direction.
In an embodiment of the disclosure, the display module further includes a light-transmitting thermal insulation board, and the light-transmitting thermal insulation board is disposed between the light guide plate and the liquid crystal display panel.
In one embodiment of the present disclosure, the light incident portion is provided with an antireflection film near the light exit surface of the light exit portion.
In one embodiment of the present disclosure, a light splitting film is disposed on the first light splitting surface and the second light splitting surface.
According to another aspect of the present disclosure, there is provided a projector including the display module set provided in one aspect of the present disclosure, a second fresnel lens, a second mirror, and an imaging lens, the second fresnel lens being disposed on a side of the liquid crystal display panel away from the light guide plate; the second reflector is arranged on the emergent light of the second Fresnel lens; the imaging lens is arranged on the reflected light of the second reflector.
The display module assembly of this disclosure includes light source and light guide plate, and the incident light of light source gets into the light guide plate, and the light guide plate includes light-emitting part, and light-emitting part includes a plurality of first beam splitting surfaces that set up along first direction, and incident light is through first beam splitting surface reflection and transmission, and reflected light is along the emergent of second direction, and the face of second direction perpendicular to light guide plate. The luminous points of the light source are dispersed into a plurality of sub luminous points through the plurality of first light splitting surfaces, so that the central brightness and the edge brightness of the backlight of the liquid crystal display panel are consistent, the difference of different areas of the display picture is small, and the uniformity of the projection picture is good.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the disclosure and together with the description, serve to explain the principles of the disclosure. It will be apparent to those of ordinary skill in the art that the drawings in the following description are merely examples of the disclosure and that other drawings may be derived from them without undue effort.
Fig. 1 is a schematic structural diagram of a projector according to an embodiment of the present disclosure.
Fig. 2 is a schematic structural view of another projector according to an embodiment of the present disclosure.
Fig. 3 is a schematic structural view of yet another projector according to an embodiment of the present disclosure.
Fig. 4 is a schematic structural view of a light source in a projector according to still another embodiment of the present disclosure.
Fig. 5 is a lateral cross-sectional view of a light guide plate according to an embodiment of the present disclosure.
Fig. 6 is a schematic optical path diagram of incident light of a light source on each second splitting surface according to an embodiment of the disclosure.
Fig. 7 is an exploded schematic view of an incident light portion according to an embodiment of the present disclosure.
Fig. 8 is a longitudinal sectional view of a light guide plate according to an embodiment of the present disclosure.
Fig. 9 is an exploded schematic view of a light emitting portion according to an embodiment of the present disclosure.
Fig. 10 is a schematic diagram illustrating the splicing of the light incident portion and the light emitting portion according to the embodiment of the disclosure.
Fig. 11 is a schematic optical path diagram of incident light of another light source according to an embodiment of the disclosure at each second light splitting surface.
In the figure: 1-light source, 11-plane illuminant, 111-base, 112-illuminant, 12-plane convex lens, 2-light guide plate, 21-light-emitting part, 210-first light-splitting surface, 211-first right-angle triangular prism, 212-first parallelogram prism, 22-light-entering part, 220-second light-splitting surface, 221-second right-angle triangular prism, 222-second parallelogram prism, 3-liquid crystal display panel, 4-light-transmitting heat-insulating board, 5-first Fresnel lens, 6-second Fresnel lens, 7-first reflector, 8-second reflector, 9-imaging lens and 10-reflecting cup.
Detailed Description
Example embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be embodied in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus detailed descriptions thereof will be omitted. Furthermore, the drawings are merely schematic illustrations of the present disclosure and are not necessarily drawn to scale.
Although relative terms such as "upper" and "lower" are used in this specification to describe the relative relationship of one component of an icon to another component, these terms are used in this specification for convenience only, such as in terms of the orientation of the examples described in the figures. It will be appreciated that if the device of the icon is flipped upside down, the recited "up" component will become the "down" component. When a structure is "on" another structure, it may mean that the structure is integrally formed with the other structure, or that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure through another structure.
The terms "a," "an," "the," "said" and "at least one" are used to indicate the presence of one or more elements/components/etc.; the terms "comprising" and "having" are intended to be inclusive and mean that there may be additional elements/components/etc. in addition to the listed elements/components/etc.; the terms "first," "second," and "third," etc. are used merely as labels, and do not limit the number of their objects.
The projector comprises a light source 1 and a liquid crystal display panel 3, wherein light rays emitted by the light source 1 are irradiated to the liquid crystal display panel 3 for imaging and then projected onto a curtain to form a projection picture for displaying. The existing projector mainly comprises two types, wherein one type is that an illumination light path adopts a plano-convex lens to conduct condensation, the other type is that an illumination light path adopts a reflecting cup 10 to conduct condensation, imaging light paths of the two types of projectors are identical, namely, after the liquid crystal display panel 3 is irradiated by light rays of the illumination light path, a generated display picture is focused by a second Fresnel lens 6, and then the display picture is projected to a curtain outside a few meters through a second reflector and a lens group to form a projection picture.
Fig. 1 shows an illumination light path employing a plano-convex lens for condensing light. The light source 1 comprises a planar light-emitting body 11 and a planar convex lens 12, the planar light-emitting body 11 comprises a base 111 and a light-emitting part 112 positioned between the base and the planar convex lens 12, light rays emitted by the light-emitting part 112 enter the planar convex lens from the plane of the planar convex lens, after being refracted by the convex surface of the planar convex lens, the light rays are incident on the surface of the first reflector 7, after being reflected by the first reflector 7, the light rays are focused through the first Fresnel lens 5, nearly parallel light is obtained, the nearly parallel light irradiates the back surface of the liquid crystal display panel 3 through the light-transmitting heat insulation plate 4, after the liquid crystal display panel 3 forms a display picture, the light emitted by the display picture is converged through the second Fresnel lens 6, and then projected onto a curtain through the second reflector and the imaging lens 9 to form a projection picture.
Fig. 2 shows an illumination light path for condensing light by using the light reflecting cup 10, the light source 1 comprises a planar light emitter 11 and a planar convex lens 12, the planar light emitter 11 comprises a base 111 and a light emitting part 112 arranged on one side of the base 111 close to the light reflecting cup 10, light emitted by the light emitting part 112 enters the light reflecting cup 10 from a light inlet of the light reflecting cup 10, the light is reflected by the inner wall of the light reflecting cup 10, exits from a light outlet of the light reflecting cup 10, and is focused by the first fresnel lens 5 to obtain nearly parallel light, and the nearly parallel light irradiates to the back of the liquid crystal display panel 3 through the light transmitting heat insulation plate 4. After the liquid crystal display panel 3 forms a display picture, light emitted by the display picture is converged by the second fresnel lens 6, and then projected onto a curtain through the second reflecting mirror and the imaging lens 9 to form a projection picture.
The two projectors have the following technical problems that the light intensity distribution of the LED light source 1 meets the lambertian body distribution, the plano-convex lens can only well collect and focus the light rays with the half angle of 0-70 degrees in the lambertian distribution, and the light rays with large angles, such as 80-90 degrees, cannot be well collected and focused, so that the partial light rays cannot be utilized, and the brightness of a projection picture is low. As for the LED light source 1 with 45W power, the brightness of the projection screen is below 180lm, and the brightness of the projection screen can reach 200lm only by using an illumination reflector with high reflectivity (the reflectivity is above 98%), an imaging reflector and a fresnel lens with high transmittance (the transmittance is above 98%).
The brightness of the projector adopting the reflecting cup 10 is higher than that of the plano-convex lens, because the light inlet of the reflecting cup 10 can utilize the light rays of the LED light source 1 with a large angle of 80 degrees to 90 degrees, the brightness of a projection picture is improved, but because the reflection of the LED light rays by the inner wall of the reflecting cup 10 is not satisfied, part of the light rays are emitted from the outlet of the reflecting cup 10 in a nearly parallel light mode, but obliquely emitted at a certain angle, and cannot reach the liquid crystal display panel 3 through the first Fresnel lens 5 and the light-transmitting heat insulation plate 4, and therefore the light efficiency of the projector is still not high. As in the conventional LED light source 1 with 90W power, the brightness of the projection screen can reach 450lm only by using an illumination reflector with high reflectivity (more than 98%), an imaging reflector and a fresnel lens with high transmittance (more than 98%).
First, in order to increase the brightness of the projector, an illumination mirror, an imaging mirror, and a fresnel lens (transmittance of 98% or more) with high reflectance (reflectance of 98% or more) are used, which increases the cost of the projector. In addition, it can be considered that the power of the light source 1 is increased, the heating phenomenon is further serious, the second fresnel lens 6 and optical devices such as lenses in the lens group work under high-brightness light, deformation can occur to cause image quality deterioration, meanwhile, the whole power of the projector can be increased, higher requirements are also provided for heat dissipation, the projector cannot work continuously for a long time, and the higher power also cannot meet the requirements of energy conservation and environmental protection. Moreover, the brightness of the projection picture is uneven, high uniformity is difficult to realize, the average brightness of 4 points in the center of the projection picture can reach 72% of the center brightness, the brightness of 4 angles of the projection picture is only 20% of the center brightness, and the viewing effect of the projection picture is that the center bright edge is dark.
Based on this, the embodiment of the disclosure provides a display module. As shown in fig. 3 to 11, the display module includes a light source 1, a light guide plate 2 and a liquid crystal display panel 3, the light guide plate 2 includes a light emitting portion 21, the light emitting portion 21 includes a plurality of first light splitting surfaces 210 arranged along a first direction, a first reflected light of the first light splitting surfaces 210 exits along a second direction, the second direction is perpendicular to a plate surface of the light guide plate 2, and the first direction is perpendicular to the second direction; the liquid crystal display panel 3 is disposed on a side of the light guide plate 2 away from the light source 1.
The incident light of the light source 1 enters the light guide plate 2, the light guide plate 2 comprises a light emitting part 21, the light emitting part 21 comprises a plurality of first light splitting surfaces 210 arranged along a first direction, the incident light is reflected and transmitted through the first light splitting surfaces 210, the first reflected light exits along a second direction, and the second direction is perpendicular to the plate surface of the light guide plate 2. The light emitting points of the light source 1 are dispersed into a plurality of sub light emitting points through the plurality of first light splitting surfaces 210, so that the central brightness and the edge brightness of the backlight of the liquid crystal display panel 3 are consistent, the difference of different areas of the display picture is small, and the uniformity of the projection picture is good.
The display module according to the embodiments of the present disclosure will be described in detail with reference to specific examples.
As shown in fig. 3, the display module includes a liquid crystal display panel 3 and an illumination light path, the illumination light path includes a light source 1, a light guide plate 2, and a light-transmitting thermal insulation plate 4, the light source 1 is disposed on a side surface of the light guide plate 2, the light-transmitting thermal insulation plate 4 is disposed on a light-emitting side of the light guide plate 2, and the liquid crystal display panel 3 is disposed on a side of the light-transmitting thermal insulation plate 4 away from the light guide plate 2. The light emitted from the light source 1 enters the light guide plate 2, and the light is emitted from the upper surface of the light guide plate 2 as nearly parallel light, and the nearly parallel light irradiates to the back surface of the liquid crystal display panel 3 through the light-transmitting heat insulation plate 4. As shown in fig. 4, the light source 1 includes a planar light emitter 11 and a planar convex lens 12, and the plane of the planar convex lens 12 is disposed near the light-emitting side of the planar light emitter 11. The light emitted by the planar illuminant 11 is focused by the planar convex lens 12 to obtain nearly parallel light, and the nearly parallel light enters the light guide plate 2 from the side surface of the light guide plate 2.
The light guide plate 2 includes a light incident portion 22 and a light emitting portion 21, the length of the light incident portion 22 is equal to the width of the light source 1, the length of the light emitting portion 21 is equal to the length of the liquid crystal display panel 3, and the orthographic projection of the liquid crystal display panel 3 on the light guide plate 2 overlaps with the light emitting portion 21. For example: the dimensions of the light source 1 were 8.5mm×8.5mm, the length of the liquid crystal display panel 3 was 98.5mm, the width was 55.4mm, the length of the light guide plate 2 was 107mm, and the width of the light guide plate 2 was 55.4mm, which was the same as the width of the liquid crystal display panel 3. It can be understood that the sum of the lengths of the light guide plate 2 and the light source 1 is equal to the length of the light guide plate 2.
As shown in fig. 5, the light incident portion 22 includes a second prism group disposed along the third direction, the second prism group includes two second right angle triangular prisms 221, a plurality of second parallelogram prisms 222 are disposed between the two second right angle triangular prisms 221, and the second right angle triangular prisms 221 are connected with the second parallelogram prisms 222 by gluing. The second right angle triangular prism 221 and the second parallelogram prism 222 have a surface roughness peak-to-valley value (PV) of 1/2 λ or less and a root mean square value (RMS) of 1/2 λ or less. Each of the second right triangular prism 221 and the second parallelogram prism 222 is provided with a second light splitting surface 220, the second light splitting surface 220 being the inclined surface of the second right triangular prism 221, and the surface of the second parallelogram prism 222 being parallel to the inclined surface of the second right triangular prism 221.
The first direction here refers to the longitudinal direction of the light guide plate 2, specifically, the x direction in fig. 5, the third direction refers to the width direction of the light guide plate 2, specifically, the z direction in fig. 5, and the second direction refers to the thickness direction of the light guide plate 2. The third direction is perpendicular to the first direction and the second direction.
As shown in fig. 6, the second light splitting surface 220 is located on the incident light of the light source 1, the incident light of the light source 1 extends along the third direction, the second light splitting surface 220 is generally provided with light splitting films with different reflectivities and transmittances, when the incident light of the light source 1 passes through each second light splitting surface 220, the transmitted light of the previous second light splitting surface 220 is split continuously on the next second light splitting surface 220, and the incident light of the light source 1 is split by the nth second light splitting surface 220 in the second prism group to form the nth second reflected light. In order to achieve that the energy of the second reflected light after the light is split by the plurality of different second light splitting surfaces 220 is the same, the relationship between the reflectivity of the nth second light splitting surface 220 and the energy of the nth second reflected light satisfies the following formula:
A 1 ＝A 0 ×K 1 (1)；
A 2 ＝A 0 ×(1-K 1 )×K 2 (2)；
A 3 ＝A 0 ×(1-K 1 )×(1-K 2 )×K 3 (3)；
……
A n ＝A 0 ×(1-K 1 )×(1-K 2 )×…×(1-K n-1 )×K n (4)；
A 1 ＝A 2 ＝…＝A n (5)；
wherein K1...kn is the reflectance of the 1 st to n th second light splitting surfaces 220, A0 is the energy of the incident light of the light source 1, and a 1..an is the energy of the n th beam of second reflected light.
As shown in fig. 7, the first second right triangular prism 221 has an A1 plane, each second parallelogram prism 222 has a B1 plane, a C1 plane, a D1 plane, and an E1 plane, and the second right triangular prism 221 has an F1 plane, and the A1 plane and the B1 plane, the C1 plane and the D1 plane, and the … …, the E1 plane and the F1 plane are glued to form a light-splitting film array waveguide having a rectangular parallelepiped structure. Wherein, the A1 surface, the C1 surface, the … … surface and the E1 surface are provided with light splitting films, different reflectivities Kn of the second light splitting surfaces 220 are realized by controlling the thickness of the light splitting films, the E1 surface is used as the last second light splitting surface 220, and the total reflection is realized by plating the light splitting films with total reflection.
As shown in fig. 8, the light-emitting portion 21 includes a first prism group disposed along a first direction, which refers to the longitudinal direction of the light guide plate 2. The first prism group includes two first right angle triangular prisms 211, a plurality of first parallelogram prisms 212 are arranged between the two first right angle triangular prisms 211, and the first right angle triangular prisms 211 are connected with the first parallelogram prisms 212 in a gluing way and the first parallelogram prisms 212 are connected with each other in a gluing way. Each of the first right triangular prism 211 and the first parallelogram prism 212 is provided with a first light splitting surface 210, the first light splitting surface 210 being the inclined surface of the first right triangular prism 211, and the surface of the first parallelogram prism 212 being parallel to the inclined surface of the first right triangular prism 211.
The first light splitting surface 210 is located on the second reflected light of the second light splitting surface 220, and the first light splitting surface 210 is generally provided with light splitting films with different reflectivities and transmittances, so that the incident light of the light source 1 is split (reflected and transmitted) when passing through each first light splitting surface 210, and the first reflected light of the first light splitting surface 210 exits along the second direction. Taking the 1 st beam of the second reflected light as an example, the transmitted light of the previous first light splitting surface 210 is further split at the next first light splitting surface 210, and the 1 st beam of the second reflected light of the second prism set is split by the m first light splitting surface 210 in the first prism set to form the m first reflected light. In order to achieve that the energy of the first reflected light after the light is split by the plurality of different first light splitting surfaces 210 is the same, the relationship between the reflectivity of the mth first light splitting surface 210 and the energy of the mth first reflected light satisfies the following formula:
B 1 ＝B 0 ×L 1 (1)；
B 2 ＝B 0 ×(1-L 1 )×K 2 (2)；
B 3 ＝B 0 ×(1-L 1 )×(1-L 2 )×L 3 (3)；
……
B m ＝B 0 ×(1-L 1 )×(1-L 2 )×…×(1-L m-1 )×L m (4)；
B 1 ＝B 2 ＝…＝B m (5)；
wherein L1.A.Lm is the reflectivity of the 1 st to m th first light splitting surfaces 210, b0 is the energy of the 1 st beam of the first reflected light, i.e. B0 is equal in size to A1, B1.
As shown in fig. 9, the first right triangular prism 211 has an A2 plane, each of the first parallelogram prisms 212 has a B2 plane, a C2 plane, a D2 plane, and an E2 plane, and the second right triangular prism 211 has an F2 plane, and the A2 plane and the B2 plane, the C2 plane and the D2 plane, and the … …, and the E2 plane and the F2 plane are glued to form a light-splitting film array waveguide having a rectangular parallelepiped structure. Wherein, the A2 plane, the C2 plane, the … … plane and the E2 plane are provided with light splitting films, different reflectivities Ln of the second light splitting planes 220 are realized by controlling the thickness of the light splitting films, the E2 plane is used as the last first light splitting plane 210, and the total reflection is realized by plating the total reflection light splitting films.
As shown in fig. 10, the G face of the second prism group along the third direction and the H face of the first prism group along the third direction may be glued together to form the light guide plate 2, an antireflection film may be plated on the G face, so as to improve the energy utilization rate of the light source 1, and the transmittance of the antireflection film is greater than 99.9%. In combination with the size of the liquid crystal display panel 3, the size and the number of prisms in the first prism group and the second prism group may be set, taking the example that the light-incident portion 22 is provided with 6 second light-splitting surfaces 220 and the light-emitting portion 21 is provided with 10 first light-splitting surfaces 210, the second prism group includes two second right-angle triangular prisms 221 and four second parallelogram prisms 222, and the first prism group includes two first right-angle triangular prisms 211 and eight second parallelogram prisms 222.
As shown in fig. 11, in other possible implementations, the light source 1 may be configured as a strip light source 1, where the length of the strip light source 1 is equal to the width of the light guide plate 2, the first light splitting surface 210 is located on a transmission light line of the second light splitting surface 220, the second light splitting surface 220 is located on an incident light line of the light source 1, and the incident light line of the light source 1 extends along the first direction. The second transmitted light of the second light splitting surface 220 is reflected by the first light splitting surface 210 and then exits along the second direction.
The embodiment of the disclosure also provides a projector. As shown in fig. 3, the projector includes the display module provided in any one of the above embodiments, a first fresnel lens 5, a second reflective mirror 8, and an imaging lens 9, where the first fresnel lens 5 is disposed on a side of the liquid crystal display panel 3 away from the light guide plate 2; the second reflector 8 is arranged on the emergent light of the first Fresnel lens 5; the imaging lens 9 is provided on the reflected light of the second mirror 8.
The light emitted by the planar light emitter 11 is shaped to nearly parallel light by the plano-convex lens near the light emitting side of the planar light emitter 11, the nearly parallel light enters the light guide plate 2 from the light inlet portion 22 of the light guide plate 2, the nearly parallel light passes through the six second light splitting surfaces 220 of the second prism group, is divided into 6 paths of second reflected light with the same luminous flux, enters the light emitting portion 21 of the light guide plate 2, passes through the ten first light splitting surfaces 210 of the first prism group, is divided into 60 paths of first reflected light with the same luminous flux, and is emitted to the back surface of the liquid crystal display panel 3. In the imaging light path, the display pictures on the liquid crystal display panel 3 are converged through the second Fresnel lens 6, and then projected onto a curtain through the second reflector and the imaging lens 9 to form projection pictures.
The light-transmitting heat insulating board 4 may be a heat insulating glass. The planar light 11 may be an LED light source 1.
The light source with the power of 45W is adopted, the light efficiency is 125lm/W, the imaging reflector with high reflectivity (the reflectivity is more than 98%) and the Fresnel lens with high transmittance (the transmittance is more than 98%) are adopted, compared with a projector adopting a plano-convex lens and a reflecting cup 10 in an illumination light path, the uniformity of four corners of a projection picture is obviously improved from the existing 20-40% to more than 60%, and the uniformity of four corners of the projection picture is improved by more than 40%. In addition, the 9-point brightness of the projector is 213lm, the light energy utilization rate of the light source is improved, and compared with the brightness of a projection picture of the projector in fig. 1 and 2, the brightness of the light source with the same power is improved by 6.5%. It can be seen that the uniformity and the screen brightness of the projector in fig. 3 are improved.
In addition, the projector in fig. 3 can improve the utilization rate of the incident light of the projector light source with a large angle, such as 80 ° to 90 °, and improve the light efficiency of the projector. The high-brightness projection can be realized by using a light source with lower power, optical devices such as the second Fresnel lens, the lens group and the like can not deform during operation, the quality of a projection picture is not influenced, and the energy-saving and environment-friendly effects are realized. On the premise of not increasing the whole power of the projector, the brightness of the projector is improved, the heat dissipation requirement is low, the volume of the projector can be reduced, the structure is compact and small, and the volume can be controlled to be within 4L.
Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any adaptations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

Claims (13)

1. A display module, comprising:
a light source;
the light guide plate comprises a light emitting part, wherein the light emitting part comprises a plurality of first light splitting surfaces arranged along a first direction, first reflected light of the first light splitting surfaces is emitted along a second direction, the second direction is perpendicular to the plate surface of the light guide plate, and the first direction is perpendicular to the second direction;
the liquid crystal display panel is arranged on one side of the light guide plate away from the light source.
2. The display module of claim 1, wherein the light-emitting portion includes a first prism group disposed along the first direction, the first prism group includes two first right-angle triangular prisms, a plurality of first parallelogram prisms are disposed between the two first right-angle triangular prisms, the first light-splitting surface is an inclined surface of the first right-angle triangular prism, and a surface of the first parallelogram prisms parallel to the inclined surface of the first right-angle triangular prism.
3. The display module of claim 1, wherein the light guide plate further comprises a light entrance portion, the light entrance portion comprises at least a plurality of second light splitting surfaces, the second light splitting surfaces are located on incident light of the light source, the first light splitting surfaces are located on second reflected light of the second light splitting surfaces, the incident light of the light source extends along a third direction, and the third direction is perpendicular to the first direction and the second direction.
4. A display module according to claim 3, wherein the light incident portion includes a second prism group disposed along a third direction, the second prism group includes two second right angle triangular prisms, a plurality of second parallelogram prisms are disposed between the two second right angle triangular prisms, the second light splitting surface is a slope of the second right angle triangular prism, and a surface of the second parallelogram prisms parallel to the slope of the second right angle triangular prism.
5. The display module of claim 4, wherein the energy of the n-th second reflected light formed by the incident light of the light source after being split by the n-th second splitting surface in the second prism group is:
A n ＝A 0 ×(1-K 1 )×(1-K 2 )×...×(1-K n-1 )×K n ；
wherein k1...Kn is the reflectance of the 1 st to n th second light splitting surfaces, A0 is the energy of the incident light of the light source, and An is the energy of the n th second reflected light.
6. The display module of claim 1, wherein the light source comprises a planar light emitter and a planar convex lens, the plane of the planar convex lens being disposed proximate the light emitting side of the planar light emitter.
7. A display module according to claim 3, wherein the light source has a dimension along the first direction equal to a dimension of the light entrance portion along the first direction.
8. The display module of claim 7, wherein the front projection of the liquid crystal display panel on the light guide plate overlaps the light emitting portion.
9. A display module according to claim 3, wherein the first light splitting surface is located on a transmission light of the second light splitting surface, the second light splitting surface is located on an incident light of the light source, and the incident light of the light source extends along the first direction.
10. The display module of claim 1, further comprising a light-transmissive insulating panel disposed between the light guide plate and the liquid crystal display panel.
11. A display module according to claim 3, wherein the light incident portion is provided with an antireflection film near the light exit surface of the light exit portion.
12. A display module according to claim 3, wherein the first light splitting surface and the second light splitting surface are provided with light splitting films.
13. A projector, comprising:
the display module of claim 1;
the second Fresnel lens is arranged on one side of the liquid crystal display panel, which is far away from the light guide plate;
the second reflector is arranged on the emergent light line of the second Fresnel lens;
and the imaging lens is arranged on the reflected light of the second reflector.
CN202310593740.XA 2023-05-23 2023-05-23 Display module and projector Pending CN116626932A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202310593740.XA CN116626932A (en) 2023-05-23 2023-05-23 Display module and projector

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202310593740.XA CN116626932A (en) 2023-05-23 2023-05-23 Display module and projector

Publications (1)

Publication Number Publication Date
CN116626932A true CN116626932A (en) 2023-08-22

Family

ID=87616585

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202310593740.XA Pending CN116626932A (en) 2023-05-23 2023-05-23 Display module and projector

Country Status (1)

Country Link
CN (1) CN116626932A (en)

Similar Documents

Publication Publication Date Title
JP3059883B2 (en) Assembly for backlighting using a microprism having a multiple reflection illumination system
CN109388013B (en) Projection screen and projection system
JPH02228689A (en) Back light display device
KR20030010533A (en) Surface lighting device
JP2013502692A (en) Concentrator for illumination optics
KR20030064258A (en) Light guide plate, light source device equipped therewith and display device
JP2003167130A (en) Light source and liquid crystal display using the light source
WO2013116970A1 (en) Novel backlight module for liquid crystal display
JP2012529670A (en) Flat panel optical display system with high control output
CN111367140A (en) Projector optical system, projector optical engine and projection method
KR20160083571A (en) Super Directional Light Guide Film And Thin Film Type Back Light Unit For Flat Panel Display Using The Same
US8313205B2 (en) Lighting device for display device, display device and television receiver
CN110361921B (en) Screen and projection system
JPS6219837A (en) Transmission type screen
CN113156707A (en) Surface light source device and flat panel display device
KR20030026325A (en) Hollow surface illuminator
CN109976037B (en) Lateral backlight source and display device thereof
CN110308511B (en) Light guide structure, side-in backlight module and display device
CN116626932A (en) Display module and projector
CN211506155U (en) Projector optical system and projector optical engine
CN110703545B (en) Projector
CN114296219A (en) Projection lens and projector
JP2006202559A (en) Surface light source apparatus
WO2020063155A1 (en) Led display screen
JP2007225853A (en) Optical sheet, backlight unit using the same and display

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination