CN114675476B

CN114675476B - Optical board and projection optical machine

Info

Publication number: CN114675476B
Application number: CN202210178580.8A
Authority: CN
Inventors: 姚春丽
Original assignee: Goertek Optical Technology Co Ltd
Current assignee: Goertek Optical Technology Co Ltd
Priority date: 2022-02-25
Filing date: 2022-02-25
Publication date: 2023-04-25
Anticipated expiration: 2042-02-25
Also published as: CN114675476A; WO2023159818A1

Abstract

The application discloses an optical board and a projection optical machine. The optical board is applied to the projection optical machine, and the optical board comprises: a metal plate having a first surface and a second surface disposed opposite each other; the baffle plate part is arranged on the first surface and is arranged on a light path when the projection optical machine is in a dark state; and a heat conductive sheet provided on the first surface and/or the second surface. The first surface and/or the second surface of the metal plate are/is provided with the heat conducting fin, and the heat conducting fin reduces the temperature inside the optical machine and the temperature of the baffle plate.

Description

Optical board and projection optical machine

Technical Field

The present application relates to the technical field of optical devices, and more particularly, to an optical board and a projection optical machine.

Background

The display mode of the digital light processing (Digital Light Processing, DLP) projection optical machine has the characteristics of high brightness, high contrast and high resolution, and can realize miniaturized portable miniature projection by combining with a novel LED light source, thereby being popular with more and more users.

The light beam adjusting module inside the projection light machine comprises various lens combinations. The lens generally is divided into glass and plastic, the lens of two kinds of materials all has respective advantage and shortcoming, and the lens weight of plastic material is less, but plastic material heat conductivility is relatively poor to the lens of plastic material is liable to produce the deformation after being heated, if the heat that gives off in the course of the work can not in time dredge the discharge, will lead to plastic lens deformation, and then influences the imaging effect of projection ray apparatus equipment.

Disclosure of Invention

An object of the present application is to provide a light machine board and a new technical solution of a projection light machine.

According to a first aspect of embodiments of the present application, an optical board is provided. The optical board is applied to the projection optical machine, and the optical board comprises:

a metal plate having a first surface and a second surface disposed opposite each other;

the baffle plate part is arranged on the first surface and is arranged on a light path when the projection optical machine is in a dark state;

and a heat conductive sheet provided on the first surface and/or the second surface.

Optionally, a notch is provided on the metal plate at a position adjacent to the baffle plate, and the notch penetrates through the first surface and the second surface; the heat conducting fin covers the notch.

Optionally, the thermally conductive sheet is a composite graphite sheet.

Optionally, the heat conductive sheet is adhered to the first surface and/or the second surface of the metal plate.

Optionally, the heat conducting sheet comprises at least two graphite sheets which are sequentially stacked, and an adhesive layer is arranged between every two adjacent graphite sheets;

a first protective film layer is arranged on one side of one graphite sheet, which faces away from the adhesive layer;

and one side of the other graphite sheet, which is away from the adhesive layer, is provided with a connecting layer, and the heat conducting sheet is adhered with the first surface and/or the second surface of the metal plate through the connecting layer.

Optionally, in a direction perpendicular to the thickness of the thermally conductive sheet, the thermally conductive sheet has a first end face and a second end face disposed opposite to each other;

the first end face is provided with a second protective film layer, and/or the second end face is provided with a third protective film layer.

Optionally, the baffle portion is integrally formed with the metal plate.

Optionally, the baffle portion includes a first baffle and a second baffle, the first baffle is connected with an edge of the metal plate, the second baffle is located on the metal plate, the second baffle is connected with an edge of the notch portion, and a shape of the second baffle is matched with a shape of the notch portion.

According to a second aspect of embodiments of the present application, a projection light engine is provided. The projection optical machine comprises the optical machine board in the first aspect.

Optionally, the projection optical machine is provided with a DMD module, and the baffle portion is located on an optical path when the DMD module is in a dark state.

Optionally, a prism assembly and a plastic lens are arranged in the projection optical machine, and the plastic lens is arranged at a position close to the prism assembly;

the baffle portion includes a first baffle and a second baffle, the first baffle is located at one side of the prism assembly, the second baffle is located at the other side of the prism assembly, and the second baffle is located between the prism assembly and the plastic lens.

Optionally, the projection optical engine is provided with a radiator, and the heat conducting fin extends to the surface of the radiator and is attached to the surface of the radiator.

In this embodiment of the application, a light machine board is provided, and a heat conducting sheet is disposed on a first surface and/or a second surface of the light machine board, and the heat conducting sheet reduces the temperature inside the light machine and the temperature of the baffle plate.

Other features of the present application and its advantages will become apparent from the following detailed description of exemplary embodiments of the present application, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description, serve to explain the principles of the application.

Fig. 1 is a schematic structural diagram of an optical board according to an embodiment of the present application.

Fig. 2 is a schematic structural diagram of another view angle of the optical board in the embodiment of the present application.

Fig. 3 is a schematic structural diagram of another view angle of the optical board according to the embodiment of the present application.

Fig. 4 is a schematic structural view of a heat conductive sheet according to an embodiment of the present application.

Reference numerals illustrate:

1. a metal plate; 11. a first surface; 12. a second surface; 13. a notch portion;

2. a baffle plate portion; 21. a first baffle; 22. a second baffle;

3. a heat conductive sheet; 31. a first graphite sheet; 32. a second graphite sheet; 33. a third graphite sheet; 34. a first adhesive layer; 35. a second adhesive layer; 36. a first protective film layer; 37. a connection layer; 38. a first release film; 39. and a second release film.

Detailed Description

Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present application unless it is specifically stated otherwise.

The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the application, its application, or uses.

Techniques and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but should be considered part of the specification where appropriate.

In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of exemplary embodiments may have different values.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.

The application provides a ray apparatus board, ray apparatus board are applied to projection ray apparatus, and ray apparatus board plays the heat conduction effect, can reduce the inside temperature of projection ray apparatus. The optical machine board can be an optical machine cover board which is covered on the bottom shell of the projection optical machine; or the optical board can be a metal board on the optical chassis. The light engine board may thus be a top or bottom plate in a projection light engine structure.

Referring to fig. 1 to 3, the optical board includes: a metal plate 1, a baffle plate portion 2, and a heat conductive sheet 3.

The metal plate 1 has a first surface 11 and a second surface 12 arranged opposite each other, the first surface 11 of the metal plate 1 being arranged, in use, towards the interior of the projection engine and the second surface 12 of the metal plate 1 being arranged away from the interior of the projection engine. The baffle portion 2 is provided on the first surface 11 of the metal plate 1, the heat conductive sheet 3 is provided on the first surface 11 and/or the second surface 12 of the metal plate 1, and the heat conductive sheet 3 is bonded to the metal plate 1, so that the temperature of the baffle portion 2 and the temperature of the lens around the baffle portion 2 can be reduced.

The first surface 11 of the metal plate 1 is provided with a baffle portion 2, and the baffle portion 2 is provided on an optical path when the projector is in a dark state. Specifically, when the projection light machine projects a dark picture, most of light rays are projected onto the baffle plate part 2, and the temperature on the baffle plate part 2 is increased; when the temperature on the barrier portion 2 increases, the temperature of the barrier portion 2 radiates to the lens in the vicinity, resulting in an increase in the lens temperature. Therefore, when the projector is in a dark state, the temperature of the barrier portion 2 and the lens around the barrier portion 2 increases inside the projector, and heat is mostly concentrated around the barrier portion 2.

In the prior art, the temperature of the baffle portion 2 and the lens around the baffle portion 2 is conducted by the metal plate, but the metal plate has limited heat conducting capability, and the temperature of the baffle portion 2 and the lens around the baffle portion 2 cannot be well reduced. Particularly, when the plastic lens exists around the baffle part 2, the temperature of the plastic lens cannot be reduced very fast, and the plastic lens can be cracked, deformed or even burnt, so that the imaging analysis and the service life of the projection optical machine are greatly influenced.

Therefore, the heat conducting fin 3 is arranged on the first surface 11 and/or the second surface 12 of the metal plate 1, the heat conducting fin 3 has a heat conducting effect, and the heat conducting fin 3 can rapidly improve the problem of heat concentration in the projection optical machine, and the baffle plate part 2 and the surrounding lenses are subjected to cooling treatment.

In one embodiment, the heat conductive sheet 3 is provided on the first surface 11 of the metal plate 1. Since the baffle portion 2 is provided on the first surface 11, when the heat conductive sheet 3 is provided on the first surface 11 of the metal plate 1, the heat conductive sheet 3 needs to be provided so as to avoid the baffle portion 2. In yet another embodiment, the heat conductive sheet 3 is provided on the second surface 12 of the metal plate 1. For example, the heat conductive sheet 3 is covered on the second surface 12. In another embodiment, the heat conductive sheet 3 is provided on both the first surface 11 and the second surface 12 of the metal plate 1.

Since the first surface 11 of the metal plate 1 is disposed towards the interior of the projection light machine, and the second surface 12 of the metal plate 1 is disposed away from the interior of the projection light machine, in use, the temperature of the first surface 11 of the metal plate 1 will be higher than the temperature of the second surface 12 of the metal plate 1, for example, the first surface 11 of the metal plate 1 will be directly irradiated by the light in the interior of the projection light machine, and the temperature of the first surface 11 is higher than the temperature of the second surface 12. In order to prevent the heat conductive sheet 3 provided on the first surface 11 from being directly subjected to direct light, and in order to prevent the adhesive of the heat conductive sheet 3 and the first surface 11 from melting in a high temperature environment, in particular, the heat conductive sheet 3 is provided on the second surface 12 of the metal plate 1.

In this application embodiment, the conducting strip 3 has the heat conduction radiating effect, and the conducting strip 3 sets up on the first surface and/or the second surface of metal sheet 1, and metal sheet 1 combines conducting strip 3, can reduce the inside temperature of projection ray apparatus, reduces the temperature of baffle portion 2 and the temperature of lens around baffle portion 2 in particular, improves the reliability of use of lens, promotes the life of projection ray apparatus. In addition, in this embodiment, the heat conducting fin 3 is disposed on the first surface 11 and/or the second surface 12 of the metal plate 1, so that the rapid heat dissipation treatment of the baffle portion 2 and the surrounding lenses thereof is realized without changing the internal structure of the projection optical machine, and the method for realizing heat dissipation of the baffle portion 2 and the surrounding lenses thereof in this embodiment is simple and has strong operability.

In one embodiment, referring to fig. 1 to 3, a notch portion 13 is provided on the metal plate 1 at a position adjacent to the baffle portion 2, and the notch portion 13 penetrates through the first surface 11 and the second surface 12; the heat conductive sheet 3 is covered with the notch 13.

In this embodiment, the notch portion 13 is formed in the metal plate 1, and the notch portion 13 is disposed near the baffle portion 2 such that the placement position of the notch portion 13 substantially corresponds to the placement position of the lens around the baffle portion 2, and the lens temperature corresponding to the notch portion 13 is relatively high. The setting position of the heat conducting strip 3 corresponds to the position of the baffle portion 2, and the setting position of the heat conducting strip 3 corresponds to the position of the notch portion 13, so that the heat conducting strip 3 can improve the heat dissipation efficiency of the baffle portion 2 and the heat dissipation efficiency of the lenses around the baffle portion 2. In this embodiment, the heat conducting strip 3 is covered on the notch portion 13, and the heat conducting strip 3 has a light blocking effect, so that some light inside the projection optical engine is prevented from being transmitted to the outside from the notch portion 13, and in addition, external light is prevented from entering the projection optical engine from the notch portion 13.

In order to reduce the temperature of the barrier portion 2 and the lens around the same as quickly as possible, the heat conductive sheet 3 is provided not only at the position corresponding to the installation position of the barrier portion 2 but also at the position corresponding to the installation position of the lens around the barrier portion 2. The heat conductive sheet 3 of the present embodiment is provided on the first surface and/or the second surface 12. For example, in a specific embodiment, the heat conductive sheet 3 may cover the second surface 12 of the metal plate 1, in which case, a portion of the heat conductive sheet 3 corresponds to the installation position of the baffle portion 2, and a portion of the heat conductive sheet 3 corresponds to the installation position of the notch portion 13.

In one embodiment, the thermally conductive sheet 3 is a composite graphite sheet.

In this embodiment, the thermally conductive sheet 3 provided on the first surface 11 and/or the second surface 12 of the metal plate 1 is a composite graphite sheet. The composite graphite sheet is used for conducting heat and dissipating heat, so that the situation that the single-layer graphite sheet is easy to break due to high brittleness is avoided. The two-dimensional plane of the composite graphite sheet has a heat conductivity coefficient as high as 1500W/(m.K), and has soaking characteristics, and the composite graphite sheet can rapidly improve the problem of heat concentration in the projection optical machine, and the baffle plate part 2 and lenses around the baffle plate part are subjected to cooling treatment.

In this embodiment, the heat conducting sheet 3 is a composite graphite sheet, the composite graphite sheet includes a black graphite sheet, and the black graphite sheet has a light blocking effect, so that some light inside the projection optical engine is prevented from being transmitted to the outside from the notch portion 13, and in addition, external light is prevented from entering the projection optical engine from the notch portion 13.

In one embodiment, the thermally conductive sheet 3 is bonded to the first surface 11 and/or the second surface 12 of the metal plate 1.

In this embodiment, the thermally conductive sheet 3 is bonded to the first surface 11 and/or the second surface 12 of the metal plate 1. For example, taking the case that the heat conducting strip 3 is adhered to the second surface 12 of the metal plate 1, the heat conducting strip 3 is prepared, the heat conducting strip 3 is positioned according to the position where the screw is avoided to be locked (namely, the metal plate 1 needs to be fixed on the bottom shell of the projection optical machine through the screw, the screw is required to be locked when the heat conducting strip 3 is positioned), after the positioning is confirmed to be correct, the heat conducting strip 3 is attached to the second surface 12 of the metal plate 1, good adhesion of the heat conducting strip 3 needs to be ensured, and the situation that the heat conducting strip 3 and the metal plate 1 are separated from each other is avoided.

In one embodiment, referring to fig. 4, the heat conducting sheet 3 includes at least two graphite sheets stacked, and an adhesive layer is disposed between adjacent graphite sheets;

one side of one of the graphite sheets facing away from the adhesive layer is provided with a first protective film layer 36;

the other side of the graphite sheet facing away from the adhesive layer is provided with a connecting layer 37, and the heat conducting strip 3 is bonded to the first surface and/or the second surface 12 of the metal plate 1 via the connecting layer 37.

In this embodiment, referring to fig. 4, the heat conductive sheet 3 includes three graphite sheets, which include a first graphite sheet 31, a second graphite sheet 32, and a third graphite sheet 33, stacked. Wherein the first graphite sheet 31 is disposed adjacent to the second graphite sheet 32, and the second graphite sheet 32 is disposed adjacent to the third graphite sheet 33.

Wherein a first adhesive layer 34 is provided between the first graphite sheet 31 and the second graphite sheet 32, and the first graphite sheet 31 and the second graphite sheet 32 are bonded by the first adhesive layer 34. For example, the first adhesive layer 34 is a double-sided adhesive structure.

Wherein a second adhesive layer 35 is provided between the second graphite sheet 32 and the third graphite sheet 33, and the second graphite sheet 32 and the third graphite sheet 33 are bonded by the second adhesive layer 35. For example, the second adhesive layer 35 is a double-sided tape structure. Wherein the first adhesive layer 34 and the second adhesive layer 35 may be the same type of adhesive layer or the first adhesive layer 34 and the second adhesive layer 35 may be different types of adhesive layers.

In this embodiment, a first protective film layer 36 is disposed on a side of the first graphite sheet 31 away from the first adhesive layer 34, and one side of the first protective film layer 36 is adhered to the first graphite sheet 31, and the first protective film layer 36 may be black single-sided tape. The first protective film layer 36 is provided as black single-sided adhesive, so that on one hand, a light blocking effect can be achieved, and on the other hand, the first graphite sheet 31 is protected through the black single-sided adhesive, and the situation that chips and the like appear on the surface of the first graphite sheet 31 is avoided.

In this embodiment, a connection layer 37 is provided on the side of the third graphite sheet 33 remote from the second adhesive layer 35, one surface of the connection layer 37 is connected to the third graphite sheet 33, and the other surface of the connection layer 37 is connected to the second surface 12 or the first surface 11 of the metal plate 1. The connection layer 37 may be a black double sided adhesive. The connection layer 37 is provided as a black double sided adhesive, which on the one hand can play a role in blocking light and on the other hand has a connection role.

In an alternative embodiment, a first release film 38 is disposed on a side of the first protective film layer 36 remote from the first graphite sheet 31. A second release film 39 is provided on the side of the connecting layer 37 remote from the third graphite sheet 33. In this embodiment, the first release film 38 and the second release film 39 protect the heat conductive sheet 3 as a whole. In use, the first release film 38 is peeled from the first protective film layer 36 and the second release film 39 is peeled from the tie layer 37.

In one embodiment, the thickness of the thermally conductive sheet 3 is in the range of 2mm to 4mm.

In this embodiment, the thickness of the heat conductive sheet 3 is defined to reduce the weight of the heat conductive sheet 3. The thickness of the heat conducting strip 3 is limited in this range in the present embodiment, and on the premise of satisfying the heat conduction and heat dissipation of the heat conducting strip 3, the heat conducting strip 3 satisfies the light weight design.

In one embodiment, the thermally conductive sheet 3 has a first end face and a second end face disposed opposite to each other in a direction perpendicular to a thickness of the thermally conductive sheet 3;

In this embodiment, the second protective film layer is disposed on the first end face of the heat conducting fin 3, and the second protective film layer plays a role of wrapping the first end face, so that the first end face of the heat conducting fin 3 is prevented from being chipped, and meanwhile, the heat conducting fin 3 is prevented from being polluted by external dust; the third protective film layer is arranged on the second end face of the heat conducting fin 3, and plays a role in wrapping the second end face, so that the phenomenon that the second end face of the heat conducting fin 3 is chipped is avoided, and meanwhile, the heat conducting fin 3 is also prevented from being polluted by external dust. For example, the second protective film layer may be a black single-sided tape, and the third protective film layer may be a black single-sided tape.

In one embodiment, referring to fig. 1 to 3, the baffle portion 2 is integrally formed with the metal plate 1.

In this embodiment, the baffle portion 2 and the metal plate 1 are integrally molded. For example, the metal plate 1 is molded by punching or injection molding, and the baffle plate portion 2 is molded on the metal plate 1 after the metal plate 1 is molded.

In one embodiment, referring to fig. 1-3, the baffle part 2 includes a first baffle 21 and a second baffle 22, the first baffle 21 is connected to the edge of the metal plate 1, the second baffle 22 is located on the metal plate 1, and the second baffle 22 is connected to the edge of the notch 13, and the shape of the second baffle 22 is matched with the shape of the notch 13.

Referring to fig. 1 and 3, the barrier section 2 includes a first barrier 21 and a second barrier 22, and the first barrier 21 and the second barrier 22 are combined to be positioned on an optical path when the projector is in a dark state. The first baffle 21 is integrally formed on the edge of the metal plate 1. For example, the first baffle 21 is formed on the edge of the metal plate 1, and when in use, the joint of the first baffle 21 and the edge of the metal plate 1 is bent, so that the first baffle 21 is bent onto the first surface 11 of the metal plate 1, that is, the plane of the first baffle 21 and the first surface 11 of the metal plate 1 form an included angle. The second baffle 22 is located on the metal plate 1 and connected to the edge of the notch portion 13. For example, the second baffle 22 is formed on the metal plate 1, and when not in use, the second baffle 22 can be completely covered on the notch 13 because the shape of the second baffle 22 matches the shape of the notch 13. When in use, the joint of the second baffle 22 and the notch 13 is bent, the notch 13 is exposed, and the second baffle 22 is bent onto the first surface 11 of the metal plate 1, that is, the plane of the second baffle 22 and the first surface 11 of the metal plate 1 form an included angle.

In this embodiment, the manner of forming the baffle portion 2 on the metal plate 1 is simple, and the operation and use by the user are facilitated.

In this embodiment, the optical machine board provided by the embodiment of the application is applied to the projection optical machine, and the optical machine board can perform heat dissipation treatment on the temperature of the baffle plate part 2 and the temperature of the lens around the baffle plate part 2, so that the temperature inside the projection optical machine is reduced, and the service life of the projection optical machine is prolonged.

In one embodiment, the projection optical machine is provided with a DMD module, and the baffle portion 2 is located on an optical path when the DMD module is in a dark state.

Specifically, the DMD module includes a DMD device having an "ON" state (i.e., an ON state) and an "OFF" state (i.e., an OFF state or referred to as a dark state), the longer the "ON" state (or the shorter the "OFF" state). Specifically, when the DMD device works, light beams are incident ON the surface of the DMD device at a certain angle, and when the DMD device is in an ON state, the light reflected by the DMD device enters a lens module of a projection optical machine and is finally projected onto a screen or a wall surface; when the DMD device is in the "OFF" state, light reflected by the DMD device needs to be prevented from entering the lens module as much as possible.

In this embodiment, the baffle portion 2 can block the light beam of the DMD module in the dark state, and simultaneously conduct heat away through the metal plate 1 and the heat conducting fin 3, so as to improve the heat dissipation efficiency of the baffle portion 2 and the surrounding lenses, and further improve the projection effect of the projection optical machine.

In one embodiment, a prism assembly and a plastic lens are arranged in the projection optical machine, and the plastic lens is arranged at a position close to the prism assembly;

the baffle part 2 includes a first baffle 21 and a second baffle 22, the first baffle 21 is located at one side of the prism assembly, the second baffle 22 is located at the other side of the prism assembly, and the second baffle 22 is located between the prism assembly and the plastic lens.

In this embodiment, the distance between the plastic lens and the baffle portion 2 and the prism assembly is relatively short, and the plastic lens is positioned such that the temperature of the plastic lens increases. In general, the prism assembly is made of glass, and the glass lens has a heat-resistant temperature higher than that of the plastic lens, so that the metal plate 1 and the heat conducting fin 3 mainly reduce the temperature of the plastic lens.

In this embodiment, the second baffle 22 is located in the lens group cavity of the projection light machine and between the prism assembly and the plastic lens, and the first baffle 21 is located at one side of the prism assembly, so that the first baffle 21 and the second baffle 22 wrap part of the top corners of the prism assembly. At this time, the light beam of the DMD module in the dark state is shielded by the baffle portion 2 before entering the lens module, and the temperature of the plastic lens can be conducted to the outside of the projection optical machine as soon as possible through the metal plate 1 and the heat conducting sheet 3, thereby preventing damage to the plastic lens.

In one embodiment, the projection optical engine is provided with a radiator, and the heat conducting fin 3 extends to the surface of the radiator and is attached to the surface of the radiator.

In this embodiment, in order to further enhance the heat dissipation effect of the heat conducting strip 3 on the inside of the projection optical engine, the heat conducting strip 3 may be extended onto the heat sink of the projection optical engine. For example, by increasing the surface area of the heat conductive sheet 3, the heat conductive sheet 3 is bonded to the surface of the heat sink, and the temperature of the baffle portion 2 and the temperature of the lens around the baffle portion 2 are further raised. In addition, the radiator arranged on the projection optical machine is generally provided with a fan, and the heat dissipation effect is further enhanced by convection heat dissipation of fan equipment.

The foregoing embodiments mainly describe differences between the embodiments, and as long as there is no contradiction between different optimization features of the embodiments, the embodiments may be combined to form a better embodiment, and in consideration of brevity of line text, no further description is given here.

Although some specific embodiments of the present application have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present application. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the present application. The scope of the application is defined by the appended claims.

Claims

1. An optical board, wherein the optical board is applied to a projection optical machine, the optical board includes:

a metal plate (1), the metal plate (1) having a first surface (11) and a second surface (12) disposed opposite to each other;

the baffle plate part (2), the baffle plate part (2) is arranged on the first surface (11), the baffle plate part (2) is arranged on a light path when the projector is in a dark state, and the baffle plate part (2) and the metal plate (1) are integrally formed;

a thermally conductive sheet (3), the thermally conductive sheet (3) being provided on the first surface (11) and/or the second surface (12);

and a notch part (13) is arranged on the metal plate (1) at a position close to the baffle part (2), the notch part (13) penetrates through the first surface (11) and the second surface (12), and the notch part (13) is covered by the heat conducting fin (3).

2. The optical board according to claim 1, characterized in that the thermally conductive sheet (3) is a composite graphite sheet.

3. The light board according to claim 1, characterized in that the thermally conductive sheet (3) is bonded to the first surface and/or the second surface (12) of the metal plate (1).

4. The optical board according to claim 1 or 2, wherein the thermally conductive sheet (3) comprises at least two graphite sheets stacked, and an adhesive layer is provided between adjacent graphite sheets;

a first protective film layer (36) is arranged on one side of one graphite sheet, which faces away from the adhesive layer;

the other side of the graphite sheet, which is far away from the adhesive layer, is provided with a connecting layer (37), and the heat conducting sheet (3) is adhered with the first surface and/or the second surface (12) of the metal plate (1) through the connecting layer (37).

5. The optical board according to claim 1, characterized in that the thermally conductive sheet (3) has a first end face and a second end face arranged opposite to each other in a direction perpendicular to the thickness of the thermally conductive sheet (3);

6. The light board according to claim 2, characterized in that the baffle part (2) comprises a first baffle (21) and a second baffle (22), the first baffle (21) is connected with the edge of the metal plate (1), the second baffle (22) is positioned on the metal plate (1), and the second baffle (22) is connected with the edge of the notch part (13), and the shape of the second baffle (22) is matched with the shape of the notch part (13).

7. A projection light engine, characterized in that the projection light engine comprises an engine board according to any one of claims 1-6.

8. The projection light engine as claimed in claim 7, characterized in that a DMD module is arranged on the projection light engine, and the baffle part (2) is located on the light path when the DMD module is in a dark state.

9. The projection light engine of claim 8, wherein a prism assembly and a plastic lens are disposed within the projection light engine, the plastic lens being disposed adjacent to the prism assembly;

the baffle part (2) comprises a first baffle (21) and a second baffle (22), the first baffle (21) is positioned on one side of the prism assembly, the second baffle (22) is positioned on the other side of the prism assembly, and the second baffle (22) is positioned between the prism assembly and the plastic lens.

10. The projection light engine according to claim 7, wherein a radiator is provided on the projection light engine, and the heat conducting sheet (3) extends to the surface of the radiator and is arranged in a fitting manner with the surface of the radiator.