Projection screen manufacturing method

Abstract

The invention discloses a manufacturing method of a projection screen. The manufacturing method comprises the following steps: firstly, manufacturing a Fresnel structure layer; a plurality of arc-shaped lens structures are arranged on the surface of one side of the Fresnel structure layer, each lens structure comprises a lens surface and a non-lens surface which are connected with each other, the lens surfaces are inclined relative to the plane where the projection screen is located, and the non-lens surfaces are used for being connected with the lens surfaces; an evaporation source is arranged at the set position of the Fresnel structure layer, and a reflecting layer is formed on the lens faces of the multiple lens structures; and manufacturing a surface function layer on the surface of one side, opposite to the reflecting layer, of the Fresnel structure layer. The reflecting layer can be formed on the lens surface of the lens structure in the Fresnel structure layer only by slightly changing the evaporation source, so that the reflecting layer is prevented from being formed on a non-lens surface.

Description

Technical Field

[0001] The invention relates to the field of projection technology, and in particular to a method for manufacturing a projection screen. Background Art

[0002] As display products continue to develop towards large-scale, considering power consumption, weight and size, the market for projection display products as large-screen products to replace LCD and organic electroluminescent (EL) TVs is rapidly expanding. The current front projection system can usually be used with a projection screen. The projection light is emitted by the projection device, and the projection light is incident on the projection screen. After being reflected by the projection screen, it is incident on the human eye and the projected image is viewed.

[0003] The projection screen usually includes a Fresnel structure layer, including multiple lens structures. The lens structure has a lens surface that is inclined relative to the plane where the projection screen is located and a non-lens surface for connecting the lens surface. The inclination angle of the lens surface is designed based on reflecting the projection light incident on the reflective layer on the inclined surface toward the audience position.

[0004] When a reflective layer is made on the surface of the Fresnel structure layer, the reflective layer is not only formed on the lens surface of the lens structure, but also usually forms reflective material on the non-lens surface, which will cause light to be reflected when it enters the non-lens surface, which is inconsistent with the original design. Summary of the invention

[0005] The method for manufacturing a projection screen provided by an embodiment of the present invention includes:

[0006] A Fresnel structure layer is manufactured; a surface of one side of the Fresnel structure layer has a plurality of arc-shaped lens structures, and each arc-shaped lens structure is concentrically arranged; each of the lens structures comprises a lens surface and a non-lens surface connected to each other, the lens surface is inclined relative to the plane where the projection screen is located, and the non-lens surface is used to connect the lens surface;

[0007] An evaporation source is arranged at a set position of the Fresnel structure layer to form a reflective layer on the lens surface of the plurality of lens structures; the evaporation source is located on one side of the Fresnel structure layer having the plurality of lens structures, and a set distance is provided between the evaporation source and the plurality of lens structures;

[0008] A surface functional layer is manufactured on the side of the Fresnel structure layer opposite to the reflective layer.

[0009] In some embodiments of the present invention, the step of setting an evaporation source at a set position of the Fresnel structure layer includes:

[0010] The arc-shaped evaporation source is arranged at a set position of the Fresnel structure layer.

[0011] In some embodiments of the present invention, the number of the evaporation source is one, and the shape of the evaporation source is a circular arc.

[0012] In some embodiments of the present invention, there are multiple evaporation sources, and the multiple evaporation sources are arranged in an arc.

[0013] In some embodiments of the present invention, there are multiple evaporation sources, and each of the evaporation sources is in the shape of a circular arc;

[0014] The multiple arcs formed by the evaporation sources are concentrically arranged, and a set distance is set between two adjacent arcs.

[0015] In some embodiments of the present invention, there are multiple evaporation sources, each of which is arranged into multiple arcs, and each arc is formed by arranging multiple evaporation sources;

[0016] The multiple arcs are concentrically arranged, and a set distance is set between two adjacent arcs.

[0017] In some embodiments of the present invention, the width of the arc-shaped evaporation source is 20 mm to 300 mm, the spacing between adjacent evaporation sources is within 300 mm, and the distance between the evaporation source and the Fresnel structure layer is 100 mm to 1000 mm.

[0018] In some embodiments of the present invention, the center of the evaporation source arranged in an arc shape coincides with the center of the lens structure in its orthographic projection on the plane where the projection screen is located; the radius of the evaporation source arranged in an arc shape is greater than the radius of any lens structure in the Fresnel structure layer;

[0019] The radius of the arc-shaped evaporation source satisfies, relative to all lens structures in the Fresnel structure layer:

[0020]

[0021] Among them, α i represents the inclination angle of the non-lens surface of the i-th lens structure relative to the normal line of the plane where the projection screen is located in a cross section along any radial direction of the Fresnel structure layer, θ i represents the inclination angle of the line connecting the innermost point of the vapor deposition source and the vertex of the i-th lens structure with respect to the normal line in the cross section, S i represents the distance from the innermost point of the evaporation source in the cross section to the normal line passing through the vertex of the i-th lens structure, and h represents the distance from the plane including the innermost point of the evaporation source to the vertex of the i-th lens structure;

[0022] The innermost point of the evaporation source is the point in the cross section that is closest to the center of a circle, and the center of a circle is the center of the evaporation source arranged in an arc shape; the vertex of the lens structure is the intersection of the lens surface and the non-lens surface of the lens structure in the cross section that are close to the evaporation source; the plane including the innermost point of the evaporation source is parallel to the plane where the projection screen is located; i is any positive integer that is less than or equal to the number of lens structures in the Fresnel structure layer.

[0023] In some embodiments of the present invention, the step of setting an evaporation source at a set position of the Fresnel structure layer includes:

[0024] Disposing an arc-shaped evaporation source at a set position of the Fresnel structure layer;

[0025] A plurality of spaced baffles are provided between the evaporation source and the plurality of lens structures, and the baffles are used to block the evaporation material emitted from the evaporation source from being formed on the non-lens surface of the lens structure.

[0026] In some embodiments of the present invention, the baffle is shaped as a partial surface of a cone; the orthographic projection of the vertex of the cone where the baffle is located on the plane where the projection screen is located coincides with the center of the lens structure.

[0027] In some embodiments of the present invention, the number of the evaporation source is one, and the evaporation source is arranged corresponding to a plurality of the baffles;

[0028] Alternatively, there are a plurality of the evaporation sources, and a baffle is disposed between every two adjacent evaporation sources.

[0029] In some embodiments of the present invention, the baffle satisfies:

[0030]

[0031] Among them, α max represents the maximum tilt angle of the non-lens surface of the lens structure relative to the normal line of the plane where the projection screen is located in a cross section along any radial direction of the Fresnel structure layer, θ represents the minimum tilt angle of the connecting line between the innermost point of the evaporation source and the edge of the baffle plate close to the Fresnel structure layer in the cross section relative to the normal line, S 1 h represents the minimum distance from the innermost point of the evaporation source in the cross section to the normal line passing through the edge of the baffle plate close to the Fresnel structure layer, 1 represents the distance from the plane including the innermost point of the evaporation source to the edge of the baffle plate close to the Fresnel structure layer;

[0032] The innermost point of the evaporation source is the point in the cross section that is closest to the center of a circle, and the center of a circle is the center of the evaporation source arranged in an arc shape; the plane including the innermost point of the evaporation source is parallel to the plane where the projection screen is located.

[0033] In some embodiments of the present invention, the width of the baffle is 100 mm to 500 mm, the spacing between adjacent baffles is 50 mm to 200 mm, and the distance between the evaporation source and the Fresnel structure layer is 20 mm to 200 mm.

[0034] In some embodiments of the present invention, the step of setting an evaporation source at a set position of the Fresnel structure layer includes:

[0035] Disposing a strip-shaped evaporation source at a set position of the Fresnel structure layer;

[0036] A plurality of spaced baffles are provided between the evaporation source and the plurality of lens structures, and the baffles are used to block the evaporation material emitted from the evaporation source from being formed on the non-lens surface of the lens structure.

[0037] In some embodiments of the present invention, the strip-shaped evaporation source extends along a first direction, the first direction is parallel to the plane where the projection screen is located, and the first direction is perpendicular to the symmetry axis of the projection screen along the vertical direction;

[0038] The baffle is in the shape of a strip extending along the first direction, the baffle is a plane, and the baffle is arranged obliquely relative to the plane where the projection screen is located.

[0039] In some embodiments of the present invention, the baffle satisfies:

[0040]

[0041] Among them, α max ' represents the maximum inclination angle of the non-lens surface of the lens structure relative to the normal line of the plane where the projection screen is located in any cross section of the projection screen along the first direction, θ' represents the minimum inclination angle of the connecting line between the innermost point of the evaporation source and the edge of the baffle plate close to the Fresnel structure layer in the cross section relative to the normal line, S 1 ' represents the minimum distance from the innermost point of the evaporation source in the cross section to the normal line passing through the edge of the baffle close to the Fresnel structure layer, h 1 ' represents the distance from the plane including the innermost point of the evaporation source to the edge of the baffle plate close to the Fresnel structure layer;

[0042] The innermost point of the evaporation source is the point in the cross section that is farthest from the corresponding side of the baffle; the plane including the innermost point of the evaporation source is parallel to the plane where the projection screen is located.

[0043] In some embodiments of the present invention, the step of forming a reflective layer on lens surfaces of the plurality of lens structures comprises:

[0044] When the evaporation source emits the evaporation material, the Fresnel structure layer is controlled to move along the first direction, so as to form a reflective layer on the lens surfaces of the plurality of lens structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings introduced below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0046] Figure 1 A schematic diagram of the structure of a projection system provided by an embodiment of the present invention;

[0047] Figure 2 A schematic diagram of the planar structure of a Fresnel structure layer provided by an embodiment of the present invention;

[0048] Figure 3 For along Figure 2 Schematic diagram of the cross-sectional structure along the A-A' direction;

[0049] Figure 4 A flowchart of a method for manufacturing a projection screen provided by an embodiment of the present invention;

[0050] Figure 5 A schematic cross-sectional structure diagram of the positional relationship between the evaporation source and the Fresnel structure layer provided in an embodiment of the present invention;

[0051] Figure 6 One of the planar structural schematic diagrams of the positional relationship between the evaporation source and the Fresnel structure layer provided in an embodiment of the present invention;

[0052] Figure 7 A second schematic planar structural diagram of the positional relationship between the evaporation source and the Fresnel structure layer provided in an embodiment of the present invention;

[0053] Figure 8 For along Figure 6 Schematic diagram of the cross-sectional structure along the I-I' direction;

[0054] Fig. 9 One of the cross-sectional structural schematic diagrams of the positional relationship between the evaporation source, the baffle and the Fresnel structure layer provided in an embodiment of the present invention;

[0055] Fig.10 A schematic plan view of the positional relationship between the baffle and the Fresnel structure layer provided in an embodiment of the present invention;

[0056] Fig.11 A second cross-sectional structural schematic diagram of the positional relationship between the evaporation source, the baffle and the Fresnel structure layer provided in an embodiment of the present invention;

[0057] Fig.12 One of the planar structural schematic diagrams of the positional relationship among the evaporation source, the baffle and the Fresnel structure layer provided in an embodiment of the present invention;

[0058] Fig.13 A second schematic planar structure diagram of the positional relationship between the evaporation source, the baffle and the Fresnel structure layer provided in an embodiment of the present invention;

[0059] Fig.14 The third schematic cross-sectional structure diagram of the positional relationship between the evaporation source, the baffle and the Fresnel structure layer provided in the embodiment of the present invention;

[0060] Fig.15 along Figure 2 Schematic diagram of the cross-sectional structure along the B-B' direction;

[0061] Fig.16 For along Fig.15 A schematic diagram showing the positional relationship between the evaporation source, the baffle and the Fresnel structure layer in the cross section shown;

[0062] Fig.17 The third schematic diagram of the planar structure of the evaporation source, the baffle and the Fresnel structure layer provided in the embodiment of the present invention;

[0063] Fig.18 A fourth schematic diagram of the planar structure of the evaporation source, the baffle and the Fresnel structure layer provided in an embodiment of the present invention;

[0064] Fig.19 A fifth schematic diagram of the planar structure of the evaporation source, the baffle and the Fresnel structure layer provided in an embodiment of the present invention;

[0065] Fig. 20 A schematic diagram of a cross-sectional structure of a reflective layer provided in some embodiments of the present invention;

[0066] Fig.21 One of the schematic cross-sectional structure diagrams of a projection screen provided by an embodiment of the present invention;

[0067] Fig. 22 A second schematic diagram of a cross-sectional structure of a projection screen provided in an embodiment of the present invention;

[0068] Fig.23A third schematic diagram of the cross-sectional structure of a projection screen provided in an embodiment of the present invention;

[0069] Fig.24 A schematic diagram of the structure of a projection device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0070] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, the present invention will be further described below with reference to the accompanying drawings and examples. However, the exemplary embodiments can be implemented in various forms and should not be understood as being limited to the embodiments described herein; on the contrary, these embodiments are provided to make the present invention more comprehensive and complete, and to fully convey the concepts of the exemplary embodiments to those skilled in the art. The same figure marks in the figures represent the same or similar structures, and thus their repeated descriptions will be omitted. The words expressing position and direction described in the present invention are all explained using the accompanying drawings as examples, but changes can be made as needed, and the changes made are all included in the scope of protection of the present invention. The drawings of the present invention are only used to illustrate the relative position relationship and do not represent the true proportions.

[0071] With the popularity of laser display products, the market for laser TVs has expanded rapidly as a large-screen product to replace LCD and organic EL TVs. In order to achieve better brightness and display effects, projection equipment is generally used with a projection screen.

[0072] Figure 1 A schematic diagram of the structure of a projection system provided by an embodiment of the present invention.

[0073] like Figure 1 As shown, the projection system includes: a projection device 2 and a projection screen 1.

[0074] The projection screen 1 is located at the light emitting side of the projection device 2. The audience faces the projection screen 1. The projection device 2 emits projection light. The projection light is incident on the projection screen 1 and is reflected forward by the projection screen 1, so that the audience can see the projected image.

[0075] The front projection type projection screen 1 can be mounted on a wall or hung at a high place. Figure 2 A schematic diagram of the planar structure of a Fresnel structure layer provided in an embodiment of the present invention.

[0076] like Figure 2 As shown, a Fresnel structure layer may be provided in the projection screen, and the Fresnel structure layer includes a plurality of lens structures F. The lens structure may adopt different structures according to different application scenarios and manufacturing processes. In the embodiment of the present invention, the functional layer composed of a plurality of lens structures F is called a Fresnel structure layer because each lens structure included in the functional layer is arc-shaped, and each arc-shaped lens structure is concentric.

[0077] The Fresnel structure includes a plurality of concentrically arranged annular lenses, and the projection screen generally does not include a complete annular Fresnel structure, so the lens structure F in the projection screen is arc-shaped and is a part of the annular lens. When the projection device is a long-focus projection device, the center O of each lens structure is located in the projection screen; when the projection device is an ultra-short-focus projection device, the projection screen generally does not include the dot O of the lens structure.

[0078] When the projection system provided by the embodiment of the present invention is applied to application scenarios such as laser television, the projection device can be an ultra-short-throw projection device, such as Figure 2 As shown, the center O of the lens structure F is usually not located inside the projection screen, but in an area outside the projection screen. The side of the projection screen close to the center O is usually the bottom side of the screen, and the radius of each lens structure F gradually increases as it gradually moves away from the bottom side. If the side of the projection screen facing the audience is called the front side, and the side away from the audience is called the back side, then in the embodiment of the present invention, each lens structure F is located at the back side of the projection screen. Arranging each lens structure at the back side of the projection screen can reduce the risk of contamination and damage caused by user contact, and ensure the long-term reliability of the Fresnel structure layer.

[0079] The following will take the projection screen used with the ultra-short-throw projection device as an example to specifically describe the structure and manufacturing method of the projection screen. However, the manufacturing method of the projection screen provided by the embodiment of the present invention is not limited to manufacturing the screen of the ultra-short-throw projection device. The manufacturing method can also manufacture screens of different types of projection devices such as short-throw and long-throw. In the specific implementation, only the relevant parameters need to be adaptively adjusted.

[0080] Figure 3 For along Figure 2 Schematic diagram of the cross-sectional structure along the A-A' direction. The A-A' direction coincides with the symmetry axis of the projection screen along the vertical direction. The projection screen provided in the embodiment of the present invention is an axisymmetric structure, and its symmetry axis is parallel to the vertical direction. When in use, the projection screen is usually set on a wall or hung at a high place, and the bottom edge of the projection screen is parallel to the horizontal direction, then the vertical direction is a direction perpendicular to the horizontal direction, and the extension line of the symmetry axis of the projection screen along the vertical direction passes through the center O of the lens structure.

[0081] like Figure 3 As shown, a Fresnel structure layer 11 is provided in the projection screen. The surface of the Fresnel structure layer 11 facing away from the projection device includes a plurality of lens structures F. Figure 2From the cross section along the A-A' direction, the shape of each lens structure F is similar to a triangle. Each lens structure F includes a lens surface x1 and a non-lens surface x2 connected to each other. The lens surface x1 is inclined relative to the plane where the projection screen is located, and the non-lens surface x2 is used to connect the lens surface x1. The inclination angle of the lens surface x1 of each lens structure F is designed according to the incident angle of the projection light, and its inclination angle satisfies that the projection light l can be reflected in the direction of the audience when it is incident on the reflective layer 12 on the surface of the lens surface x1. In this way, more projection light can be reflected in the direction of the audience, while reducing the reflection of ambient light in the direction of the audience, thereby improving the brightness and contrast of the projected image.

[0082] When making a reflective layer on the surface of the Fresnel structure, according to the original design, it is hoped that the reflective layer will be formed only on the lens surface x1 of the lens structure, and not on the non-lens surface x2. The reflective layer is usually made by evaporation or sputtering, but the current manufacturing process of the reflective layer will not only form a reflective layer on the lens surface x1 of the lens structure, but also on the non-lens surface x2, which will cause light to be reflected when it enters the non-lens surface x2, which is inconsistent with the original design.

[0083] In view of this, an embodiment of the present invention provides a method for manufacturing a projection screen. Figure 4 A flowchart of a method for manufacturing a projection screen provided by an embodiment of the present invention.

[0084] like Figure 4 As shown, the method for making a projection screen includes:

[0085] S10, making a Fresnel structure layer;

[0086] S20, arranging an evaporation source at a set position of the Fresnel structure layer to form a reflective layer on lens surfaces of the multiple lens structures;

[0087] S30, manufacturing a surface functional layer on the side of the Fresnel structure layer opposite to the reflection layer.

[0088] The embodiment of the present invention is specifically described by taking the evaporation process as an example to make the reflective layer. In addition to the evaporation process, the reflective layer can also be made by sputtering or similar processes. The reflective layer can be made of a metal material with reflective properties, such as aluminum, silver, titanium, etc. In addition, the reflective layer can also adopt a multi-layer structure, which can achieve selective reflection of incident light, thereby further improving the contrast of the projected image.

[0089] By improving the structure and position of the evaporation source, the embodiment of the present invention can form a reflective layer only on the lens surface of the lens structure, avoiding the reflective layer from being formed on the non-lens surface of the lens structure. The production process of the projection screen is described in detail below.

[0090] The Fresnel structure layer 11 may include a substrate and a lens structure F located on the substrate, wherein the lens structure F may be manufactured by using a mold having a Fresnel structure and a UV molding process using an ultraviolet curing resin.

[0091] Before manufacturing the reflective layer 12 on the surface of the lens structure F, it is necessary to design the structure and location of the evaporation source, and the design can be in various forms.

[0092] Figure 5 A schematic cross-sectional structure diagram of the positional relationship between the evaporation source and the Fresnel structure layer provided in an embodiment of the present invention; Figure 6 One of the planar structural schematic diagrams of the positional relationship between the evaporation source and the Fresnel structure layer provided in an embodiment of the present invention; Figure 7 A second schematic planar structural diagram of the positional relationship between the evaporation source and the Fresnel structure layer provided in an embodiment of the present invention; Figure 8 For along Figure 6 Schematic diagram of the cross-sectional structure along the I-I' direction.

[0093] like Figure 5 As shown, the evaporation source W is disposed on a side of the Fresnel structure layer 11 having the lens structure F, and there is a certain distance between the evaporation source W and the lens structure F. The evaporation source radiates the evaporation material isotropically in a working state.

[0094] In some embodiments, Figure 6 and Figure 7 As shown, when making the reflective layer, at least one evaporation source W arranged in an arc shape can be used. Figure 6 As shown, the number of the evaporation source W can be one, and the size of the evaporation source W is relatively large and the shape is a circular arc; or Figure 7 As shown, there are multiple evaporation sources W, the size of the evaporation sources W is relatively small, and the evaporation sources W are arranged in an arc.

[0095] The evaporation source will isotropically radiate the evaporation material when evaporating the reflective layer. The evaporation source W is arranged in an arc shape so that the orthographic projection of the center of the evaporation source W on the plane where the projection screen is located coincides with the center of the lens structure F, so that the evaporation material can be relatively evenly formed on the lens structure F.

[0096] In order to prevent the evaporation source W from forming the evaporation material on the non-lens surface x2 of the lens structure F, when the radius of the evaporation source W arranged in an arc shape is larger than the radius of any lens structure F in the Fresnel structure layer, only the evaporation material emitted from the evaporation source W toward the side of the center O will be incident on the lens surface x1 of the lens structure F, thereby preventing the evaporation material from being incident on the non-lens surface x2 of the lens structure F.

[0097] Figure 5 to Figure 7The evaporation source W is arranged in the form of an arc as an example for illustration. In the specific implementation, the evaporation source W can also be arranged in multiple arcs. In this case, multiple evaporation sources are needed. In some embodiments, the size of the evaporation source is relatively large, and the shape of each evaporation source is an arc. Multiple evaporation sources can be arranged in multiple concentric arcs. In some embodiments, the size of each evaporation source is relatively small. These evaporation sources are arranged into multiple arcs, and each arc is formed by arranging multiple evaporation sources.

[0098] When the evaporation source is arranged in multiple arcs, each arc can be arranged concentrically, and the radius of each arc needs to be greater than the radius of any lens structure F in the Fresnel structure layer. According to this design idea, the minimum radius of the evaporation source arranged in an arc shape can be determined.

[0099] Specifically, if Figure 8 As shown, in the order of the radius of each lens structure F from small to large, the non-lens surface of the m-th lens structure relative to the normal t m The inclination angle is α m , the non-lens surface of the nth lens structure is relative to the normal t n The inclination angle is α n .exist Figure 8 In the cross section shown, the line connecting the innermost point P of the evaporation source and the vertex of the m-th lens structure is aligned with the normal line t m The inclination angle is θ m , the line connecting the evaporation source W and the vertex of the nth lens structure relative to the normal t n The inclination angle is θ n The vertical distance from the plane including the innermost point P of the evaporation source to the vertex of the lens structure F is h, and the normal line from the innermost point P of the evaporation source to the vertex of the mth lens structure is t m The distance is S m , the normal line t from the innermost point P of the evaporation source to the vertex of the nth lens structure n The distance is S n .

[0100] Among them, the normal t m ,t n is the normal line of the plane where the projection screen is located. The normal lines t claimed in the embodiments of the present invention are all perpendicular to the plane where the projection screen is located. Figure 8 The Fresnel structure layer 11 shown includes a substrate. The plane where the projection screen is located may be parallel to the plane where the substrate of the Fresnel structure layer 11 is located. Therefore, the plane where the projection screen is located in the embodiment of the present invention may refer to Figure 8 The plane where the Fresnel structure layer 11 is located, and the normal line of the plane where the projection screen is located is referred to as the normal line hereinafter.

[0101] like Figure 6 As shown, from the perspective of the planar structural relationship, the evaporation source is arranged in an arc shape, and the orthographic projection of the center of the evaporation source arranged in an arc shape on the plane where the projection screen is located coincides with the center of the arc-shaped lens structure, and the radius of the evaporation source arranged in an arc shape is greater than the radius of all circular lens structures. When the evaporation source W emits the evaporation material, it usually radiates isotropically. When the side of the evaporation source W that emits the evaporation material is arranged opposite to the side of the Fresnel structure layer 11 having the lens structure F, as shown in FIG. Figure 6 As shown in FIG. 1 , only the evaporation material emitted from the innermost periphery of the evaporation source W can be incident on the lens structure F. Then, in the cross section along the radial direction, as shown in FIG. Figure 8 As shown, the innermost point P of the evaporation source refers to the point of the evaporation source closest to the center O in the cross section, that is, Figure 8 The rightmost point of the evaporation source. Figure 8 It can be seen that in the cross section along any radial direction, the inclination angle of the evaporated material emitted from the innermost point P of the evaporation source relative to the normal when it is incident on the vertex of the lens structure is usually smaller than the inclination angle of the evaporated material emitted from other positions of the evaporation source relative to the normal when it is incident on the vertex of the same lens structure. Therefore, the minimum inclination angle formed by the line connecting the innermost point P of the evaporation source and the vertex of the lens structure F is taken into consideration.

[0102] like Figure 8 As shown, the vertex of the lens structure F refers to the intersection of the lens surface x1 and the non-lens surface x2 of the lens structure F on the side close to the vapor deposition source W in any cross section.

[0103] According to the trigonometric function relationship:

[0104]

[0105]

[0106] In order to prevent the evaporation material emitted by the evaporation source W from being formed on the non-lens surface x2 of the Fresnel structure, the m-th lens structure needs to satisfy α m <θ m , for the nth lens structure, α needs to be satisfied n <θ n Then, when the evaporation source W satisfies the above relationship for each lens structure F, the minimum radius R that the evaporation source W arranged in an arc shape should satisfy can be found.

[0107] Figure 8 An arc-shaped evaporation source is used as an example, and Figure 8 The cross section shown is a cross section along the symmetry axis II' of the projection screen. When more arc-shaped evaporation sources are used or the evaporation sources are arranged into multiple concentric arcs, the cross section of each arc along any radial direction satisfies:

[0108]

[0109] Among them, α i represents the inclination angle of the non-lens surface of the i-th lens structure F in the cross section along any radial direction of the Fresnel structure layer relative to the normal of the plane where the projection screen is located, θ i S represents the inclination angle of the line connecting the innermost point of the vapor deposition source and the vertex of the i-th lens structure F with respect to the normal line in the cross section. i represents the distance from the innermost point of the evaporation source to the normal line passing through the vertex of the i-th lens structure in the cross section, and h represents the distance from the plane including the innermost point of the evaporation source to the vertex of the lens structure F.

[0110] The definitions of the normal line, the innermost point of the evaporation source in the cross section, and the vertex of the lens structure can refer to the above embodiments and will not be repeated here. Figure 8 The plane including the innermost point P of the evaporation source refers to a plane passing through the point P and parallel to the plane where the projection screen is located.

[0111] The position of the evaporation source satisfies that the inclination angle of the line connecting the vertices of any lens structure with respect to the normal of the plane where the projection screen is located is greater than the inclination angle with respect to the non-lens surface of the lens structure. Therefore, when the evaporation source radiates the evaporation material to the Fresnel structure layer, the evaporation material can be prevented from being incident on the non-lens surface of each lens structure.

[0112] In specific implementation, the inclination angle of the lens surface x1 of each lens structure F in the Fresnel structure layer 11 relative to the plane where the projection screen is located, and the inclination angle of the non-lens surface x2 of each lens structure F relative to the normal of the plane where the projection screen is located may vary. Then the evaporation source needs to be set according to the actual situation.

[0113] Specifically, when the projection screen is used in an ultra-short-throw projection system, the projection device is usually located below the projection screen, and the projection light is emitted obliquely upward to the projection screen. If the projection light is to be reflected toward the audience, the inclination angle of the lens surface x1 of each lens structure F in the Fresnel structure layer 11 relative to the plane where the projection screen is located satisfies: the inclination angle of the lens surface x1 increases with the increase of the radius of the lens structure. Figure 5 and Figure 8 As shown, in the projection screen used in the ultra-short-throw projection system, the center O of the Fresnel structure is located outside the projection screen, and Figure 5 and Figure 8 In the schematic diagram of the cross-sectional structure shown, the farther away from the center O, the greater the inclination angle of the lens surface x1 of the lens structure F relative to the plane where the projection screen is located.

[0114] For the non-lens surface x2 of each lens structure F, its inclination angle relative to the normal line of the plane where the projection screen is located may change along with the lens surface x1, or may remain unchanged.

[0115] In some embodiments, Figure 5 As shown, the inclination angles of the non-lens surface x2 of each lens structure F relative to the normal line t of the plane where the projection screen is located are the same. For example, the non-lens surface x1 of each lens structure F is perpendicular to the plane where the projection screen is located, that is, α in the above formula (1) i =0. Then the position of the arc-shaped evaporation source W satisfies that in any cross section along the radial direction, the inclination angle of the connection between the innermost point of the evaporation source W and the vertex of any lens structure F in the cross section relative to the normal of the plane where the projection screen is located is greater than 0, that is, θ in the above formula (1) is i >0.

[0116] In some embodiments, Figure 8 As shown in FIG. 1 , the inclination angle of the non-lens surface x2 of each lens structure F relative to the normal line t of the plane where the projection screen is located increases with the increase of the radius of the lens structure F, that is, Figure 8 In the cross-sectional view shown in n >α m Then, when the evaporation source W is set for this situation, the maximum value of the inclination angles of the non-lens surface x2 in the Fresnel structure layer 11 relative to the normal of the plane where the projection screen is located is the inclination angle of the non-lens surface of the lens structure with the largest radius. Therefore, the evaporation source W satisfies that the inclination angle of the line connecting the innermost point of the evaporation source and the vertex of the lens structure with the largest radius in the cross section along any radial direction of the Fresnel structure layer relative to the normal is greater than the inclination angle of the non-lens surface of the lens structure with the largest radius relative to the normal. The above normals are all normals to the plane where the projection screen is located.

[0117] In a specific implementation, the distance between the evaporation source and the Fresnel structure layer can be 100 mm to 1000 mm, the width of the evaporation source arranged in an arc shape can be 20 mm to 300 mm, and the spacing between two adjacent circular evaporation sources can be within 300 mm. For example, the vertical distance between the evaporation source and the Fresnel structure layer can be 300 mm, the width of the evaporation source arranged in an arc shape can be 100 mm, and the spacing between two adjacent circular evaporation sources can be 20 mm.

[0118] Fig. 9 One of the cross-sectional structural schematic diagrams of the positional relationship between the evaporation source, the baffle and the Fresnel structure layer provided in an embodiment of the present invention; Fig.10 A schematic plan view of the positional relationship between the baffle and the Fresnel structure layer provided in an embodiment of the present invention; Fig.11A second cross-sectional structural schematic diagram of the positional relationship between the evaporation source, the baffle and the Fresnel structure layer provided in an embodiment of the present invention; Fig.12 One of the planar structural schematic diagrams of the positional relationship among the evaporation source, the baffle and the Fresnel structure layer provided in an embodiment of the present invention; Fig.13 The second schematic planar structure diagram of the positional relationship among the evaporation source, the baffle and the Fresnel structure layer provided in the embodiment of the present invention.

[0119] In some embodiments, Fig. 9 As shown, a vapor deposition source W can be set on one side of the Fresnel structure layer 11 having multiple lens structures F, so that the vapor deposition source W and the multiple lens structures F are at a set distance; and a plurality of spaced-apart baffles D are set between the vapor deposition source W and the multiple lens structures F, so that the baffles D block the vapor deposition material emitted by the vapor deposition source W from being formed on the non-lens surface x2 of the lens structure F.

[0120] Specifically, a plurality of baffles D are arranged between the evaporation source W and the Fresnel structure layer 11, which can block the evaporation source W from emitting the evaporation material onto the non-lens surface x2 of the lens structure F. Since the lens surface and the non-lens surface of the lens structure F may have different inclination angles, the baffle D usually needs to be arranged at an angle, and the inclination angles of the baffles at different positions may be different. The inclination angle of each baffle needs to be set according to the standard that the evaporation material emitted by the evaporation source near it is not formed on the non-lens surface x of the lens structure F at the corresponding position after being blocked by the baffle D. In the specific implementation, the width of the lens structure F is in the micrometer range, and the spacing distance of the baffle D can be tens of millimeters or more. The scheme in which the evaporation source W and the baffle D cooperate with each other can make the distance between the evaporation source W and the Fresnel structure layer 11 not too large, and can avoid the uneven evaporation caused by the long distance between the evaporation source W and the distal lens structure.

[0121] The evaporation source W can be arranged in an arc shape, and accordingly, the baffle D is shaped as a part of a conical surface, such as Fig.10 The figure shows the plane structure of the baffle D. In the plane structure, the overall outline of the baffle D is an arc. From the perspective of the three-dimensional structure, the orthographic projection of the vertex of the conical surface where the baffle D is located on the plane where the projection screen is located coincides with the center of the lens structure F.

[0122] In some embodiments, Fig. 9 As shown, the evaporation source W may have a relatively large width. In this case, only one evaporation source W is required. The evaporation source W may correspond to a plurality of baffles D, thereby reducing the number of evaporation sources W used.

[0123] In some embodiments, Fig.11As shown, the evaporation source W may have a relatively small width and be in multiple numbers. In this case, a baffle D may be provided between each two adjacent evaporation sources W, thereby enabling a more sophisticated design of the evaporation source and the baffle. Fig.12 and Fig.13 As shown, the evaporation source W can be arranged in multiple arcs. Fig.12 The number of evaporation sources W can be multiple, each evaporation source W is in the shape of a circular arc, and the arc-shaped evaporation sources W can be concentrically arranged. Fig.13 The number of the evaporation sources W can be multiple, and the evaporation sources W are discretely arranged. The evaporation sources W are dispersedly arranged into multiple concentric arcs, and each arc is formed by arranging multiple evaporation sources.

[0124] In order to prevent the evaporated material from being formed on the non-lens surface x2 of each lens structure F, the baffle D has a certain inclination angle. The inclination angle satisfied by the baffle is specifically described below.

[0125] Fig.14 The third cross-sectional structural schematic diagram of the positional relationship among the evaporation source, the baffle and the Fresnel structure layer provided in the embodiment of the present invention. Fig.14 Shown along Fig.12 The cross-sectional structure in the I-I' direction is as follows: Fig.14 As shown, the non-lens surface x2 of the lens structure F is inclined at an angle α relative to the normal line t of the plane where the projection screen is located. Fig.14 In the cross section shown, the line connecting the innermost point P of the evaporation source and the edge of the baffle D corresponding to it close to the Fresnel structure layer has an inclination angle θ relative to the normal line t. Fig.14 In the cross section shown, the vertical distance from the innermost point P of the evaporation source to the normal line passing through the edge of the baffle D close to the Fresnel layer is S 1 The distance from the plane including the innermost point of the evaporation source to the edge of the baffle D close to the Fresnel structure layer is h 1 .

[0126] The definitions of the normal line, the innermost point of the evaporation source in the cross section, and the plane including the innermost point of the evaporation source may refer to the above embodiments and will not be repeated here.

[0127] According to the trigonometric function relationship:

[0128]

[0129] Among them, the function of the baffle D is to block the evaporated material from being incident on the non-lens surface x2 of the lens structure F. Therefore, the baffle is usually inclined toward the center O of the lens structure F. Then, in order to enable the baffle D to block the evaporation source W from emitting the evaporated material to the non-lens surface x2 of the lens structure F, it is necessary to make the minimum inclination angle of the line connecting the innermost point of any evaporation source in the cross section along any radial direction of the Fresnel structure layer to the edge of the corresponding baffle close to the Fresnel structure layer relative to the normal of the plane where the projection screen is located be greater than the maximum inclination angle of the non-lens surface x2 of the lens structure F relative to the normal.

[0130] Fig.14 Taking the cross section along the symmetry axis II' of the projection screen as an example, when setting the inclination angle of the baffle, it is necessary to make the inclination angle of the baffle in the cross section along any radial direction of the Fresnel structure layer satisfy:

[0131]

[0132] Among them, α max represents the maximum tilt angle of the non-lens surface of the lens structure relative to the normal of the plane where the projection screen is located in a cross section along any radial direction of the Fresnel structure layer, θ represents the minimum tilt angle of the connecting line between the innermost point of the evaporation source and the edge of the baffle plate close to the Fresnel structure layer in the cross section relative to the normal, S 1 h represents the distance from the innermost point of the evaporation source in the cross section to the normal line passing through the edge of the baffle plate close to the Fresnel structure layer. 1 It represents the distance from the plane including the innermost point of the evaporation source to the edge of the baffle plate on the side close to the Fresnel structure layer.

[0133] The definitions of the normal line, the innermost point of the evaporation source in the cross section, and the plane including the innermost point of the evaporation source may refer to the above embodiments and will not be repeated here.

[0134] As described above, in practical applications, the inclination angle of the lens surface x1 of each lens structure F in the Fresnel structure layer 11 relative to the plane where the projection screen is located, and the inclination angle of the non-lens surface x2 of each lens structure F relative to the normal of the plane where the projection screen is located may vary. Still taking the projection screen used in the ultra-short-throw projection system as an example, the inclination angle of the lens surface x1 of each lens structure F in the Fresnel structure layer 11 relative to the plane where the projection screen is located increases with the increase of the radius of the lens structure F. For the non-lens surface x2 of each lens structure F, its inclination angle relative to the normal of the plane where the projection screen is located may change with the lens surface x1, or may remain unchanged.

[0135] In some embodiments, Fig.11As shown, the non-lens surface x2 of each lens structure F has the same inclination angle relative to the normal line t of the plane where the projection screen is located. For example, the non-lens surface x1 of each lens structure F is perpendicular to the plane where the projection screen is located, that is, α=0 in the above formula (2). In this case, the inclination angles of each baffle D located between the evaporation source W and the Fresnel structure layer 11 can be the same, and the baffles D are parallel to each other.

[0136] In some embodiments, Fig.14 As shown, the inclination angle of the non-lens surface x2 of each lens structure F relative to the normal t of the plane where the projection screen is located increases with the increase of the radius of the lens structure F, that is, the larger the radius of the lens structure F, the larger the inclination angle of the non-lens surface x2 of the lens structure F relative to the normal. In this case, the inclination angle of the baffle D needs to be set according to the lens structure F to which it corresponds. The width of the lens structure F is usually in the micrometer order, and the width of the baffle D is usually in the millimeter order. Therefore, one baffle D will correspond to multiple lens structures F. Then, according to the above formula (2), the angle of the line connecting the edge of the baffle D close to the Fresnel structure layer and the innermost point of the corresponding evaporation source relative to the normal needs to be greater than the maximum angle of the non-lens surface x2 in each lens structure F corresponding to the baffle D relative to the normal.

[0137] In a specific implementation, the distance between the evaporation source and the Fresnel structure layer can be 20 mm to 200 mm, the evaporation source is arranged close to the side of the baffle away from the Fresnel structure layer, the width of the baffle can be 100 mm to 500 mm, and the spacing between adjacent baffles can be 50 mm to 200 mm. For example, the distance between the evaporation source and the Fresnel structure layer can be 100 mm, the width of the baffle can be 200 mm, and the spacing between adjacent baffles can be 100 mm.

[0138] Fig.15 For along Figure 2 Schematic diagram of the cross-sectional structure along the B-B' direction; Fig.16 For along Fig.15 The schematic diagram of the positional relationship between the evaporation source, the baffle and the Fresnel structure layer in the cross section shown. Figure 2 The BB' direction and the AA' direction are parallel to each other, that is, they are both parallel to the symmetry axis II' of the projection screen along the vertical direction.

[0139] In some embodiments, Fig.15 and Fig.16As shown, a vapor deposition source W can be set on one side of the Fresnel structure layer 11 having multiple lens structures F, so that the vapor deposition source W and the multiple lens structures F are at a set distance; and a plurality of spaced-apart baffles D are set between the vapor deposition source W and the multiple lens structures F, so that the baffles D block the vapor deposition material emitted by the vapor deposition source W from being formed on the non-lens surface x2 of the lens structure F.

[0140] and Fig.12 The embodiment shown differs in that Fig.15 The cross section shown is along Figure 2 The cross section in the B-B' direction, when parallel to Figure 2 When all cross sections of the Fresnel structure layer are cut in the B-B' direction, the size of the inclination angle α' of the non-lens surface x2 of the lens structure F relative to the normal t of the plane where the projection screen is located will change. If the maximum inclination angle α of the non-lens surface x2 of the lens structure F relative to the normal of the plane where the projection screen is located is found in a certain cross section max ', then the positional relationship between the baffle D and its corresponding evaporation source W can satisfy:

[0141]

[0142] Among them, Fig.16 As shown, α max ' represents the maximum tilt angle of the non-lens surface x2 of the lens structure F obtained in all cross sections of the Fresnel structure layer 11 along the direction parallel to BB' relative to the normal of the plane where the projection screen is located, θ' represents the minimum tilt angle of the connecting line between the innermost point P of the evaporation source and the edge of the corresponding baffle D close to the Fresnel structure layer in the cross section relative to the normal t, S 1 ' represents the distance from the innermost point P of the evaporation source in the cross section to the normal line t passing through the edge of the baffle D close to the Fresnel structure layer, h 1 ' represents the distance from the plane including the innermost point P of the evaporation source to the edge of the baffle plate close to the Fresnel structure layer.

[0143] The normal line is the normal line of the plane where the projection screen is located. The innermost point of the evaporation source refers to the point on the side of the evaporation source farthest from the corresponding baffle in the above cross section, for example, Fig.16 The left side of the evaporation source W is closer to the baffle D, and the right side of the evaporation source is farther away from the baffle. Fig.16 The innermost point of the evaporation source refers to the rightmost point of the evaporation source. The plane including the innermost point P of the evaporation source refers to a plane passing through the point P and parallel to the plane where the projection screen is located.

[0144] When the positional relationship between the baffle D and the corresponding evaporation source W satisfies the above formula (3), the structures of the baffle D and the evaporation source W can be simplified. Specifically, Fig.17 The third schematic diagram of the planar structure of the evaporation source, the baffle and the Fresnel structure layer provided in the embodiment of the present invention; Fig.18 The fourth schematic diagram of the planar structure of the evaporation source, baffle and Fresnel structure layer provided in the embodiment of the present invention.

[0145] At this time, if Fig.17 As shown, the evaporation source W can be set to a strip extending along the first direction a, and the baffle D can be set to a strip extending along the first direction a. The baffle D is no longer a complex structure such as a conical surface, but is set to a plane.

[0146] The first direction a is parallel to the plane where the projection screen is located and perpendicular to the symmetry axis II' of the projection screen along the vertical direction.

[0147] This can avoid the deposition material from being formed on the non-lens surface of the lens structure while simplifying the structures of the deposition source and the baffle.

[0148] Furthermore, if Fig.18 As shown, if the Fresnel structure layer is moved along the first direction a during evaporation, a film can be formed on the lens surface of the lens structure, thereby improving the productivity of the reflective layer. If combined with a roll-to-roll process, the productivity of the projection screen can be further improved.

[0149] In a specific implementation, the distance between the evaporation source and the Fresnel structure layer can be 20 mm to 200 mm, the evaporation source is arranged close to the side of the baffle away from the Fresnel structure layer, the width of the baffle can be 100 mm to 500 mm, and the spacing between adjacent baffles can be 50 mm to 500 mm. For example, the distance between the evaporation source and the Fresnel structure layer can be 100 mm, the width of the baffle can be 200 mm, and the spacing between adjacent baffles can be 100 mm.

[0150] According to the same inventive concept, when the functional layer in the projection screen no longer adopts a Fresnel structure, but is composed of multiple lens structure layers extending along the above-mentioned first direction and arranged along the symmetry axis II' direction along the vertical direction of the projection screen, the structure of the evaporation source and baffle in the above-mentioned embodiment can also be applied.

[0151] Specifically, Fig.19 The fifth schematic diagram of the planar structure of the evaporation source, baffle and Fresnel structure layer provided in the embodiment of the present invention. Fig.19As shown, the projection screen has a functional layer 11', and the functional layer 11' includes a plurality of lens structures F', which are all strip-shaped extending along a first direction a, and are arranged along the direction of the symmetry axis I-I' of the projection screen along each lens structure F. The first direction a is parallel to the plane where the projection screen is located, and the first direction a is perpendicular to the symmetry axis I-I' of the projection screen along the vertical direction. Similarly, the lens structure F' includes a lens surface and a non-lens surface that are connected to each other, wherein the lens surface is tilted relative to the plane where the projection screen is located, and the non-lens surface is used to connect the lens surface so that the tilt angle of the lens surface relative to the plane where the projection screen is located satisfies that the projection light incident on the reflective layer on the lens surface can be reflected in the direction where the audience is located.

[0152] For the functional layer 11' that satisfies the above lens structure F', the evaporation source W and the baffle D can both be strip-shaped extending along the first direction a, and the baffle D is a plane. The structures of the functional layer 11', the evaporation source W and the baffle D are simplified.

[0153] When parallel to Fig.19 When all cross sections of the functional layer 11' are cut along the I-I' direction, the cross-sectional structure obtained is the same as that along Fig.19 Therefore, the positional relationship between the baffle D and its corresponding evaporation source W should be the same as the above formula (2), thereby preventing the evaporation material emitted by the evaporation source W from being formed on the non-lens surface of the lens structure F'.

[0154] When the projection screen is used in an ultra-short-throw projection system, the inclination angle of the lens surface of each lens structure F' in the functional layer 11' relative to the plane where the projection screen is located increases as the distance between the lens structure F' and the bottom edge of the projection screen increases. Fig.19 As shown, the bottom edge of the projection screen is Fig.19 The lower side of the projection screen. If the non-lens surfaces of the lens structures F' have the same inclination angle relative to the normal of the plane where the projection screen is located, for example, when the non-lens surfaces of the lens structures F' are arranged perpendicular to the plane where the projection screen is located, then the inclination angles of the baffles D located between the evaporation source W and the functional layer 11' may be the same, and the baffles D are parallel to each other. If the inclination angle of the non-lens surface of each lens structure F' relative to the normal of the plane where the projection screen is located increases as the distance between the lens structure F' and the bottom edge of the projection screen increases, then the inclination angle of the baffle D needs to be set according to the corresponding lens structure F', and the baffles D are no longer parallel to each other.

[0155] In specific implementation, the reflective layer can be a single-layer structure or a multi-layer composite structure. When the reflective layer is a single-layer structure, any of the above methods can be used to evaporate the reflective metal material on the lens surface of the lens structure. When the reflective layer is a multi-layer composite structure, it can achieve selective reflection of light in a specific wavelength band, thereby further improving the contrast of the projected image.

[0156] Specifically, Fig. 20 Schematic diagram of the cross-sectional structure of the reflective layer provided in some embodiments of the present invention. Fig. 20 As shown, the reflective layer 12 of the multi-layer composite structure may include: a semi-transparent layer 121, a reflective layer 122 and a transparent medium layer 123. The semi-transparent layer 121, the transparent medium layer 123 and the reflective layer 122 are sequentially formed on the lens surface of the Fresnel structure. The semi-transparent layer 121, the transparent medium layer 123 and the reflective layer 122 form a resonance structure.

[0157] Among them, the semi-transparent layer 121 has a semi-transparent and semi-reflective property. It should be noted that the semi-transparent and semi-reflective properties mentioned in the embodiment of the present invention do not mean that the transmittance and reflectance of the light are both 50%, but to show that the semi-transparent layer 121 can achieve the property of partially transmitting and partially reflecting the light. Its transmittance and reflectance can be adjusted according to actual requirements. The specific transmittance and reflectance of the semi-transparent layer 121 are not limited here. The semi-transparent layer 121 can make the projection light incident on the reflection layer F when it is incident on the projection screen, and can also be emitted from one side of the semi-transparent layer 121 after the oscillation of the projection light in the resonance structure is enhanced. In the specific implementation, the semi-transparent layer 121 can adopt a laminated structure formed by at least one metal of Al, Nb, Ag and Ti.

[0158] The reflective layer 122 has the function of reflecting light. The reflective layer 122 is located on the side away from the audience and does not need to transmit light. Therefore, it can be made of a material with reflective properties but no light-transmitting properties. In specific implementation, the reflective layer 122 can be made of materials such as Al, aluminum alloy, Ag or silver alloy, and the thickness of the reflective layer 122 is greater than the thickness of the semi-transmitting layer 121.

[0159] The thickness of the transparent medium layer 123 determines the cavity length of the resonance structure, so the product of the refractive index and thickness of the transparent medium layer 123 determines the wavelength of the light that can be reflected. Therefore, when designing the resonance structure, it is necessary to select a dielectric material whose refractive index and thickness product satisfies the conditions for the projection light emitted by the projection device to resonate. In specific implementation, the transparent medium layer 123 can be made of materials such as metal oxides, nitrides or transparent resins.

[0160] The semi-transparent layer 121, the transparent medium layer 123 and the reflective layer 122 can all be made by sputtering or evaporation process. By improving the evaporation source or the sputtering source in any form as described above, it is possible to form a reflective layer only on the lens surface of the lens structure and avoid forming a reflective layer on the non-lens surface. Alternatively, it is also possible to improve only the reflective layer 122 or only improve both the reflective layer 122 and the semi-transparent layer 121 in any of the above forms.

[0161] When the reflective layer of the multi-layer composite structure is used, a dielectric material with a suitable refractive index is selected as the light-transmitting medium layer, and the light-transmitting medium layer is set to a suitable thickness, so that the reflection of the projection light by the resonance structure can be enhanced.

[0162] When the projection light source adopts a three-color laser light source device, the three-color laser light source device can emit red laser, green laser and blue laser. Then, by adjusting the refractive index and thickness of the material of the transparent medium layer, the resonance structure can simultaneously enhance the reflection of red laser, green laser and blue laser, while attenuating the reflection of light in other bands, thereby improving the contrast of the projected image.

[0163] Finally, after the reflective layer is made, the surface functional layer can also be made. The surface functional layer is located on the outermost side of the projection screen, that is, the side closest to the audience. The surface functional layer plays a role in protecting the projection screen. In addition, the surface functional layer can also be processed in a variety of ways according to different needs to achieve the effects of expanding the viewing angle, resisting ambient light reflection, and resisting ceiling reflection.

[0164] Fig.21 One of the schematic cross-sectional structure diagrams of a projection screen provided by an embodiment of the present invention; Fig. 22 A second schematic diagram of a cross-sectional structure of a projection screen provided in an embodiment of the present invention; Fig.23 The third schematic diagram of the cross-sectional structure of the projection screen provided in the embodiment of the present invention.

[0165] In some embodiments, Fig.21 and Fig. 22 As shown, the surface functional layer can be a diffusion layer 13, which can increase the divergence angle of the light emitted from the projection screen, thereby increasing the viewing angle of the audience viewing the projection image. In addition, the diffusion layer 13 is also conducive to eliminating laser speckles and optimizing the projection image.

[0166] The diffusion layer 13 can be made in a variety of ways, such as Fig.21As shown, a bonding layer 14 can be formed on the surface of the Fresnel structure layer 11 opposite to the lens structure F, and then the diffusion layer and the Fresnel structure layer 11 are bonded to each other through the bonding layer. The diffusion layer 13 can include a substrate and a diffusion material formed on the surface of the substrate, or the diffusion material can be directly doped into the substrate so as to bond to the Fresnel structure layer 11.

[0167] Or, if Fig. 22 As shown, the surface of the Fresnel structure layer 11 opposite to the reflective layer 12 may be directly sandblasted to form the diffusion layer 13. In this way, the surface of the Fresnel structure layer 11 opposite to the reflective layer 12 may become rough, thereby having a light diffusion effect.

[0168] In addition, if Fig.23 As shown, a light absorbing layer 15 can also be formed on the side of the Fresnel structure layer 11 having the reflective layer 12, and the light absorbing layer 15 can absorb the light incident on the non-lens surface x2 of the lens structure, so that the light incident on the projection screen is more reflected on the lens surface of the lens structure according to the original design.

[0169] The following is a detailed introduction to the structure of the ultra-short-throw projection system. Fig.24 A schematic diagram of the structure of a projection device provided in an embodiment of the present invention.

[0170] like Figure 2 As shown, the ultra-short-throw projection system may specifically include: a projection device 2 and a projection screen 1, wherein the projection screen 1 is located on the light-emitting side of the projection device 2, the audience faces the projection screen 1, the projection device 2 emits projection light, the projection light is incident on the projection screen 1, and is reflected forward by the projection screen 1, so that the audience can view the projected image.

[0171] For an ultra-short-throw projection system, the distance between the projection device 2 and the projection screen 1 is usually small, but the projection screen can project a larger screen. In order to reduce the projection ratio to below 0.4, the projection lens in the projection device needs to be reasonably designed.

[0172] like Fig.24 As shown, the projection device may include: Figure 1 As shown, the projection device includes: a light source device 10, an illumination system 20 and a projection lens 30. The illumination system 20 is located at the light-emitting side of the light source device 10, the illumination system 20 includes a light modulator 201, and the projection lens 30 is located at the light-emitting side of the light modulator 201.

[0173] Among them, the light source device 10 can adopt a laser light source device, and the laser light source device can adopt a monochromatic laser or a laser that can emit lasers of multiple colors or multiple lasers that emit lasers of different colors. When the laser light source device adopts a monochromatic laser, the laser display device also needs to be provided with a color wheel, and the color wheel is used for color conversion. The monochromatic laser cooperates with the color wheel to realize the emission of primary color lights of different colors in a time sequence. When the laser light source device adopts a laser that can emit lasers of multiple colors, it is necessary to control the laser light source to emit lasers of different colors as primary color lights in a time sequence.

[0174] In the embodiment of the present invention, a three-color laser light source device can be used. The three-color laser light source device can be a laser that emits three primary color lasers, such as an MCL laser, etc.; it can also include a red laser, a green laser, and a blue laser that emit three primary color lasers respectively. The use of a three-color laser light source device is conducive to improving the color gamut of the projected image, has better color expression, and can accurately reproduce the input image.

[0175] The laser light source device may also include a light combining component for combining three-color lasers. The light combining component may include a reflector and a dichroic mirror. The number and position of the reflector and the dichroic mirror may be set according to the arrangement rule of the laser chips in the laser to achieve the combination of three-color lasers.

[0176] The lighting system 20 is located on the light-emitting side of the light source device 10, and the lighting system 20 includes a light modulator 201. The lighting system 20, on the one hand, shapes and homogenizes the outgoing light beam of the light source device 10, and on the other hand, can make the outgoing light of the light source device 10 incident on the light modulator 201 at a suitable angle, thereby modulating the incident light to generate a display image. The lighting system 20 may also include a light homogenizing element 202, a plurality of lenses or a lens group 203, so that the lighting beam is homogenized and shaped before being incident on the light modulator 201. The light homogenizing element 202 may be a light pipe or a compound eye lens group, etc., which is not limited here.

[0177] The projection device provided in the embodiment of the present invention may adopt a digital light processing (DLP) system. In a specific implementation, the light modulation device 201 may adopt a digital micromirror (DMD). The surface of the DMD includes many tiny mirrors, each of which can be driven to deflect individually. By controlling the deflection angle of the DMD, the brightness of the reflected light of each tiny mirror is controlled, thereby generating a display image. In addition, the light modulation device 201 may also adopt a liquid crystal on silicon (LCoS) device or a liquid crystal display (LCD). The embodiment of the present invention takes the light modulation device 201 adopting DMD as an example for illustration.

[0178] The projection lens 30 is used to image the output light of the light modulation component 201, so that the audience can see a larger size display image. In the ultra-short-throw projection system, the projection lens 30 usually adopts an ultra-short-throw projection lens, which includes multiple lenses. Depending on the actual application scenario, these lenses may have different numbers and surface shapes, which are not specifically limited here.

[0179] The projection screen 1 can receive the imaging light emitted by the projection lens 30 and reflect the light toward the audience, so that the audience can watch the display screen. In the projection screen manufactured by the method for manufacturing a projection screen provided by the embodiment of the present invention, a reflective layer is only provided on the lens surface of the lens structure. By improving the setting position and structure of the evaporation source, the formation of a reflective layer on the non-lens surface of the lens structure can be avoided. Only minor improvements to the evaporation source are required to maintain the original design of the projection screen, which will not cause an increase in cost and is conducive to improving production efficiency.

[0180] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0181] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for manufacturing a projection screen, characterized in that: include: A Fresnel structure layer is manufactured; a surface of one side of the Fresnel structure layer has a plurality of arc-shaped lens structures, and each arc-shaped lens structure is concentrically arranged; each of the lens structures comprises a lens surface and a non-lens surface connected to each other, the lens surface is inclined relative to the plane where the projection screen is located, and the non-lens surface is used to connect the lens surface; An evaporation source is arranged at a set position of the Fresnel structure layer to form a reflective layer on the lens surface of the plurality of lens structures; the evaporation source is located on one side of the Fresnel structure layer having the plurality of lens structures, and a set distance is provided between the evaporation source and the plurality of lens structures; A surface functional layer is manufactured on the side of the Fresnel structure layer opposite to the reflective layer.

2. The method according to claim 1, characterized in that: The evaporation source is arranged at a set position of the Fresnel structure layer, comprising: The arc-shaped evaporation source is arranged at a set position of the Fresnel structure layer.

3. The method according to claim 2, characterized in that: The number of the evaporation source is one, and the shape of the evaporation source is a circular arc.

4. The method according to claim 2, characterized in that: There are multiple evaporation sources, and the multiple evaporation sources are arranged in an arc.

5. The method according to claim 2, characterized in that: There are multiple evaporation sources, and each of the evaporation sources is in the shape of an arc; The multiple arcs formed by the evaporation sources are concentrically arranged, and a set distance is set between two adjacent arcs.

6. The method according to claim 2, characterized in that: There are multiple evaporation sources, each of which is arranged into multiple arcs, and each arc is formed by arranging multiple evaporation sources; The multiple arcs are concentrically arranged, and a set distance is set between two adjacent arcs.

7. The production method according to claim 5 or 6, characterized in that: The width of the arc-shaped evaporation source is 20 mm to 300 mm, and the distance between adjacent evaporation sources is within 300 mm; the distance between the evaporation source and the Fresnel structure layer is 100 mm to 1000 mm.

8. The production method according to any one of claims 3 to 6, characterized in that: The center of the evaporation source arranged in an arc shape coincides with the center of the lens structure in its orthographic projection on the plane where the projection screen is located; the radius of the evaporation source arranged in an arc shape is greater than the radius of any lens structure in the Fresnel structure layer; The radius of the arc-shaped evaporation source satisfies, relative to all lens structures in the Fresnel structure layer: Among them, α i represents the inclination angle of the non-lens surface of the i-th lens structure relative to the normal line of the plane where the projection screen is located in a cross section along any radial direction of the Fresnel structure layer, θ i represents the inclination angle of the line connecting the innermost point of the vapor deposition source and the vertex of the i-th lens structure with respect to the normal line in the cross section, S i represents the distance from the innermost point of the evaporation source in the cross section to the normal line passing through the vertex of the i-th lens structure, and h represents the distance from the plane including the innermost point of the evaporation source to the vertex of the i-th lens structure; The innermost point of the evaporation source is the point in the cross section that is closest to the center of a circle, and the center of a circle is the center of the evaporation source arranged in an arc shape; the vertex of the lens structure is the intersection of the lens surface and the non-lens surface of the lens structure in the cross section that are close to the evaporation source; the plane including the innermost point of the evaporation source is parallel to the plane where the projection screen is located; i is any positive integer that is less than or equal to the number of lens structures in the Fresnel structure layer.

9. The method according to claim 1, characterized in that: The evaporation source is arranged at a set position of the Fresnel structure layer, comprising: Disposing an arc-shaped evaporation source at a set position of the Fresnel structure layer; A plurality of spaced baffles are provided between the evaporation source and the plurality of lens structures, and the baffles are used to block the evaporation material emitted from the evaporation source from being formed on the non-lens surface of the lens structure.

10. The manufacturing method according to claim 9, characterized in that: The baffle is in the shape of a partial surface of a cone; the orthographic projection of the vertex of the cone where the baffle is located on the plane where the projection screen is located coincides with the center of the lens structure.

11. The method according to claim 10, characterized in that: The number of the evaporation source is one, and the evaporation source is arranged corresponding to a plurality of the baffles; Alternatively, there are a plurality of the evaporation sources, and a baffle is disposed between every two adjacent evaporation sources.

12. The method according to claim 10, characterized in that: The baffle meets the following requirements: Among them, α max represents the maximum inclination angle of the non-lens surface of the lens structure relative to the normal of the plane where the projection screen is located in a cross section along any radial direction of the Fresnel structure layer, θ represents the minimum inclination angle of the connecting line between the innermost point of the evaporation source in the cross section and the edge of the baffle plate close to the Fresnel structure layer relative to the normal, S1 represents the minimum distance from the innermost point of the evaporation source in the cross section to the normal passing through the edge of the baffle plate close to the Fresnel structure layer, and h1 represents the distance from the plane including the innermost point of the evaporation source to the edge of the baffle plate close to the Fresnel structure layer; The innermost point of the evaporation source is the point in the cross section that is closest to the center of a circle, and the center of a circle is the center of the evaporation source arranged in an arc shape; the plane including the innermost point of the evaporation source is parallel to the plane where the projection screen is located.

13. The manufacturing method according to claim 10, characterized in that: The width of the baffle is 100 mm to 500 mm, the spacing between adjacent baffles is 50 mm to 200 mm, and the distance between the evaporation source and the Fresnel structure layer is 20 mm to 200 mm.

14. The method according to claim 1, characterized in that: The evaporation source is arranged at a set position of the Fresnel structure layer, comprising: Disposing a strip-shaped evaporation source at a set position of the Fresnel structure layer; A plurality of spaced baffles are provided between the evaporation source and the plurality of lens structures, and the baffles are used to block the evaporation material emitted from the evaporation source from being formed on the non-lens surface of the lens structure.

15. The manufacturing method according to claim 14, characterized in that: The strip-shaped evaporation source extends along a first direction, the first direction is parallel to the plane where the projection screen is located, and the first direction is perpendicular to the symmetry axis of the projection screen along the vertical direction; The baffle is in the shape of a strip extending along the first direction, the baffle is a plane, and the baffle is arranged obliquely relative to the plane where the projection screen is located.

16. The method of claim 15, wherein: The baffle meets the following requirements: Among them, α max ' represents the maximum inclination angle of the non-lens surface of the lens structure relative to the normal of the plane where the projection screen is located in any cross section of the projection screen along the first direction, θ' represents the minimum inclination angle of the connecting line between the innermost point of the evaporation source and the edge of the baffle plate close to the Fresnel structure layer in the cross section relative to the normal, S1' represents the minimum distance from the innermost point of the evaporation source in the cross section to the normal of the edge passing through the baffle plate close to the Fresnel structure layer, and h1' represents the distance from the plane including the innermost point of the evaporation source to the edge of the baffle plate close to the Fresnel structure layer; The innermost point of the evaporation source is the point in the cross section that is farthest from the corresponding side of the baffle; the plane including the innermost point of the evaporation source is parallel to the plane where the projection screen is located.

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