Method for designing roller mold, method for manufacturing optical sheet material, and optical sheet material

Abstract

The invention relates to the technical field of optical plate manufacturing, in particular to a design method of a roller mold, a manufacturing method of an optical plate and the optical plate. In the design method of the roller mold, the roller mold is provided with a peripheral surface and a plurality of first microstructures arranged on the peripheral surface, and is used for extruding a second microstructure corresponding to the shape of the first microstructure on the surface of resin in a molten state, and manufacturing a target optical plate with a plurality of target microstructures on the surface based on the second microstructure. One of the first microstructure and the second microstructure is convex, the other of the first microstructure and the second microstructure is concave, the target microstructure is limited by the second microstructure, and the design method comprises the following steps: determining the value of k and the value of a according to the material of a target optical plate, the thickness of the target optical plate and the period of the target microstructure; and determining the depth or height X1 of the first microstructure based on a relational expression X1 = k * Y1 + a, and Y1 is the height or depth of the target microstructure.

Description

Technical Field

[0001] The present application relates to the technical field of optical plate manufacturing, and in particular to a roller mold design method, an optical plate manufacturing method and an optical plate. Background Art

[0002] Optical sheet refers to a plate-like material with excellent optical properties, which is widely used in various optical devices and electronic products. The types of materials used to form optical sheets mainly include optical grade PC (Polycarbonate), optical grade PMMA (Polymethyl Methacrylate) board, and MS resin (styrene-methyl methacrylate copolymer) board. The structure of the optical sheet is different in different usage scenarios. For example, when used in the backlight system of electronic products, a micro-nano structure can be processed on at least one of the two main surfaces of the optical sheet to make a light guide plate that controls the transmission of light and changes the light propagation path. In order to adapt to new optical requirements and improve the utilization of light, when the optical sheet is produced and formed, a microstructure is often formed on one surface of the optical sheet by transfer using a roller mold.

[0003] When a microstructure is transferred onto one surface of an optical plate using a roller mold with a microstructure, it is usually not possible to make the microstructure on the optical plate and the microstructure on the roller mold 100% complementary in shape and size, and the size of the microstructure on the optical plate will be smaller than the size of the microstructure on the roller mold. Therefore, in order to achieve the microstructure size (for example, height or depth) required for the optical plate, the depth or height of the microstructure on the roller mold needs to be appropriately increased. In the past, technicians usually relied entirely on experience to select the initial increase in the depth or height of the microstructure on the roller mold, and then repeatedly reduced or increased the aforementioned increase according to the size of the microstructure on the manufactured optical plate, which increased the product development cost and was highly dependent on technicians. Summary of the invention

[0004] In view of this, the present application proposes a roller mold design method, an optical plate manufacturing method and an optical plate.

[0005] In a first aspect, a design method (200) of a roller mold (3) is provided, wherein the roller mold (3) has a peripheral surface (3a) and a plurality of first microstructures (301) disposed on the peripheral surface (3a), and is used to extrude a second microstructure (RE1) corresponding to the shape of the first microstructure (301) on the surface of a molten resin (RE), and based on this, manufacture a target optical plate (1) having a plurality of target microstructures (101) on the surface, wherein one of the first microstructure (301) and the second microstructure (RE1) is a protrusion and the other is a depression, and the target microstructure (101) is defined by the second microstructure (RE1), and the design method (200) comprises: Determining the value of k and the value of a according to the material of the target optical plate (1), the thickness (DD) of the target optical plate (1) and the period (Pitch) of the target microstructure (101); Based on the relationship X1=k*Y1+a, the depth or height X1 of the first microstructure (301) is determined, wherein Y1 is the height or depth of the target microstructure (101).

[0006] The method of determining the value of k and the value of a according to the material of the target optical plate (1), the thickness (DD) of the target optical plate (1), and the period (DD) of the target microstructure (101) comprises: Providing a second resin corresponding to the material of the target optical plate (1), a second roller mold having a second peripheral surface and a plurality of third microstructures arranged on the second peripheral surface, and a third roller mold having a third peripheral surface and a plurality of fourth microstructures arranged on the third peripheral surface, wherein the third microstructure, the fourth microstructure and the first microstructure (301) are all protrusions or are all depressions, the period of the third microstructure and the period of the fourth microstructure correspond to the period of the target microstructure (101), the depth or height of the third microstructure is X2, the depth or height of the fourth microstructure is X3, and X2≠X3; Using the second roller mold, a fifth microstructure corresponding to the shape of the third microstructure is pressed out on the surface of the second resin in a molten state, and based on this, a second optical plate having a plurality of sixth microstructures on the surface is manufactured, wherein the sixth microstructures are defined by the fifth microstructures, and the thickness of the second optical plate is the same as the thickness (DD) of the target optical plate (1); Using the third roller mold, a seventh microstructure corresponding to the shape of the fourth microstructure is pressed out on the surface of the second resin in a molten state, and based on this, a third optical plate having a plurality of eighth microstructures on the surface is manufactured, wherein the eighth microstructure is defined by the seventh microstructure, and the thickness of the third optical plate is the same as the thickness (DD) of the target optical plate (1); The height or depth of the sixth microstructure is measured to be Y2, and the height or depth of the eighth microstructure is measured to be Y3; Based on the relationships X2=k*Y2+a and X3=k*Y3+a, determine the value of k and the value of a.

[0007] In some possible implementations, the method of determining the value of k and the value of a according to the material of the target optical plate (1), the thickness (DD) of the target optical plate (1), and the period (Pitch) of the target microstructure (101) comprises: If the thickness (DD) of the target optical plate (1) is less than 0.7 mm, the value of a is determined to be 0.

[0008] If the thickness of the target optical plate (1) is less than 0.7 mm, the value of a is determined to be 0, including: In some possible implementations, if the thickness of the target optical plate (1) is less than 0.6 mm, the value of a is determined to be 0.

[0009] In some possible implementations, the method of determining the value of k and the value of a according to the material of the target optical plate (1), the thickness (DD) of the target optical plate (1), and the period (Pitch) of the target microstructure (101) comprises: Providing a third resin corresponding to the material of the target optical plate (1), and a fourth roller mold having a fourth peripheral surface and a plurality of ninth microstructures arranged on the fourth peripheral surface, wherein the ninth microstructure and the first microstructure (301) are both the protrusions or the depressions, and the period of the ninth microstructure corresponds to the period (Pitch) of the target microstructure (101), and the depth or height of the ninth microstructure is X4; Using the fourth roller mold, a tenth microstructure corresponding to the shape of the ninth microstructure is pressed out on the surface of the third resin in a molten state, and based on this, a fourth optical plate having a plurality of eleventh microstructures on the surface is manufactured, wherein the eleventh microstructure is defined by the tenth microstructure, and the fourth optical plate has the same thickness (DD) as the target optical plate (1); The height or depth of the eleventh microstructure is measured to be Y4; Based on the relationship X4=k*Y4, determine the value of k.

[0010] In some possible implementations, the material of the target optical plate (1) is selected from PMMA resin, MS resin or PC resin.

[0011] In some possible embodiments, the first microstructure (301) is configured to extend along the circumferential direction (DR3) of the roller mold (3), and the plurality of first microstructures (301) are arranged in sequence in the axial direction (DR4) of the roller mold (3); or, The first microstructure (301) is configured to extend along the axial direction (DR4) of the roller mold (3), and the plurality of first microstructures (301) are arranged in sequence in the circumferential direction (DR3) of the roller mold (3); or, The plurality of first microstructures (301) are configured as island-shaped depressions or island-shaped protrusions that are separated from one another on the peripheral surface (3a) of the roller mold (3).

[0012] In a second aspect, a method (300) for manufacturing a target optical plate (1) is provided, comprising: Designing a roller mold (3) according to the design method (200) described in the first aspect; Manufacturing the roller mold (3); The target optical plate (1) is manufactured using the roller mold (3).

[0013] In some possible implementations, the method of manufacturing the target optical plate (1) using the roller mold (3) comprises: bringing the resin (RE) into a molten state; The second microstructure (RE1) is pressed out on the surface (S1) of the resin (RE) in a molten state by using the cooperation between the roller mold (3) and the pressing rollers (4, 5); Cooling the resin (RE) from which the second microstructure (RE1) is pressed, so that the resin (RE) becomes a solidified state; affixing a protective film (PF) to a surface (S1) of the cured resin (RE) on which the second microstructure (RE1) is pressed; The resin (RE) to which the protection film (PF) is attached is cut.

[0014] In some possible implementations, the method of manufacturing the target optical plate (1) using the roller mold (3) comprises: The target optical plate (1) is manufactured using an optical plate manufacturing device (100) comprising the roller mold (3), wherein the optical plate manufacturing device (100) comprises: A first pressing roller (4) forms a first roller pair (RP1) with the roller mold (3), wherein the first roller pair (RP1) is configured to allow a molten resin (RE) to pass through a first space (SP1) between the first pressing roller (4) and the roller mold (3), and to extrude the resin (RE) at the first space (SP1) to extrude the second microstructure (RE1) on a surface (S1) of the resin (RE); The cooling roller (6, 7, 8) is arranged on the downstream side of the roller mold (3) and is constructed to cool the resin (RE) by contacting the other surface (S2) of the resin (RE) on which the second microstructure (RE1) is pressed, wherein the other surface (S2) is the surface of the resin (RE) opposite to the second microstructure (RE1).

[0015] In some possible implementations, the optical plate manufacturing device (100) further includes: The second pressing roller (5) is arranged on the side of the roller mold (3) opposite to the first pressing roller (4) and on the upstream side of the cooling rollers (6, 7, 8), and forms a second roller pair (RP2) with the roller mold (3). The second roller pair (RP2) is constructed to allow the resin (RE) drawn out through the first roller pair (RP1) to pass through a second space (SP2) between the second pressing roller 5 (5) and the roller mold (3), and to support the resin (RE) in the second space (SP2) to optimize the shape of the second microstructure (RE1).

[0016] In a second aspect, a target optical plate (1) is provided. The target optical plate (1) is manufactured by the manufacturing method (300) as described in the second aspect.

[0017] In some possible implementations, the target optical plate (1) has a first main surface (1a) and a second main surface (1b) that are arranged opposite to each other in the thickness direction thereof, and the plurality of target microstructures (101) are formed on the first main surface (1a).

[0018] In some possible embodiments, the target microstructure (101) is constructed in the shape of a long strip extending along a first direction (DR1), and the plurality of target microstructures (101) are arranged in sequence in a second direction (DR2) intersecting the first direction (DR1), and the first main surface (1a) is defined by the first direction (DR1) and the second direction (DR2); or, The plurality of target microstructures (101) are configured as island-shaped protrusions or island-shaped depressions separated from each other on the first main surface (1a).

[0019] According to the roller mold design method provided in the present application, the structural parameters of the corresponding roller mold, especially the dimensional parameters of the microstructure on the roller mold, can be quickly and accurately determined according to the material, thickness, microstructure period and microstructure size of the target optical plate, thereby helping to reduce the development cost of the optical plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings in the following description only relate to some embodiments of the present application, rather than limiting the present application.

[0021] Figure 1 It is a schematic diagram of the structure of the optical plate manufacturing equipment provided in the embodiment of the present application.

[0022] Figure 2 yes Figure 1 Enlarged schematic view at the first roller pair.

[0023] Figure 3 yes Figure 1 FIG. 1 is a schematic side view of the roller mold when viewed from its radial direction.

[0024] Figure 4 yes Figure 1 Partial schematic diagram of the middle roller mold.

[0025] Figure 5 It is a partial schematic diagram of the optical plate provided in the embodiment of the present application.

[0026] Figure 6 It is a partial schematic diagram of a roller mold provided in another embodiment of the present application.

[0027] Figure 7 It is a partial schematic diagram of an optical plate provided in another embodiment of the present application.

[0028] Figure 8 It is a partial schematic diagram of a roller mold provided in another embodiment of the present application.

[0029] Fig. 9 It is a partial schematic diagram of an optical plate provided in another embodiment of the present application.

[0030] Fig.10 It is a schematic side view of a roller mold provided by another embodiment of the present application when observed from its radial direction.

[0031] Fig.11 It is a partial schematic diagram of a roller mold provided in another embodiment of the present application.

[0032] Fig.12 It is a partial schematic diagram of an optical plate provided in another embodiment of the present application.

[0033] Fig.13 It is a partial schematic diagram of a roller mold provided in another embodiment of the present application.

[0034] Fig.14 It is a partial schematic diagram of an optical plate provided in another embodiment of the present application.

[0035] Fig.15 It is a schematic diagram of fitting data in multiple experimental examples provided in the embodiments of the present application.

[0036] Fig.16 It is a schematic diagram of fitting data in multiple experimental examples provided in the embodiments of the present application.

[0037] Fig.17 It is a schematic diagram of fitting data in multiple experimental examples provided in the embodiments of the present application.

[0038] Fig.18 It is a flow chart of the design method of the roller mold provided in the embodiment of the present application.

[0039] Fig.19 It is a flow chart of the design method of the roller mold provided in the embodiment of the present application.

[0040] Fig. 20 It is a flow chart of the design method of the roller mold provided in the embodiment of the present application.

[0042] Fig.21 It is a flow chart of the manufacturing method of the optical plate provided in the embodiment of the present application.

[0043] Fig. 22 It is a flow chart of the manufacturing method of the optical plate provided in the embodiment of the present application.

[0044] Description of reference numerals: 100- Optical sheet manufacturing equipment; 200- Design methods; 300- Manufacturing method; DR1 - first direction; DR2 - second direction; DR3 - circumferential direction; DR4-axial direction; 1-optical plate, 101-microstructure, 1a-first main surface, 1b-second main surface; 2- Extrusion die; 3-roller mold, 301-first microstructure, 3a-circumferential surface; 4-first pressing roller; 5- second pressing roller; 6, 7, 8-cooling rollers; 9, 10, 11, 12, 13 - conveyor rollers; 14-protective film unwinding roller; 15, 16-film laminating roller; RE-resin, RE1-second microstructure, S1-first surface, S2-second surface; PF-protective film; SP1-first space, SP2-second space; RP1 - first roller pair, RP2 - second roller pair. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme of the embodiment of the present application will be clearly and completely described below in conjunction with the drawings of the embodiment of the present application. Obviously, the described embodiment is a part of the embodiment of the present application, rather than all the embodiments. Based on the described embodiment of the present application, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of this application. It can be understood that, in the absence of conflict, some technical means of the various embodiments described herein can be replaced or combined with each other.

[0046] In the description of this application, if there are terms such as "first", "second", etc., they are only used to distinguish the objects described and do not have any order or technical meaning. Therefore, an object defined as "first", "second", etc. may explicitly or implicitly include one or more of the objects, and, for example, the term "first element" itself does not mean the existence of the "second element", and the term "second element" itself does not mean the existence of the "first element". In addition, "one" or "a" and similar words do not indicate a quantity limitation, but rather indicate the existence of at least one, and "multiple" means not less than two.

[0047] In the description of the present application, the terms “including”, “having” indicate the existence of the described features, numbers, operations, elements and / or their combinations, but do not exclude the existence or addition of one or more other features, numbers, operations, elements and / or their combinations.

[0048] In the description of the present application, if there are similar terms such as "configured to" or "structured to", they can generally be interchanged with "having the ability to", "designed to", "for" or "capable of", depending on the context.

[0049] In the description of the present application, reference to "one embodiment" or "some embodiments" etc. means that one or more embodiments of the present application include a particular feature, structure or characteristic described in conjunction with the embodiment. Thus, the phrases "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. appearing in different places in the present specification do not necessarily all refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways.

[0050] Before introducing the design method of the roller mold provided in the embodiment of the present application, an optical plate manufacturing device including such a roller mold (hereinafter, sometimes referred to as the device 100) and related findings of the inventor are first introduced.

[0051] See also Figure 1 , Figure 1 A portion of an optical plate manufacturing apparatus 100 is shown, and the portion shown includes an extrusion die 2 , a roller die 3 , a first pressing roller 4 , a second pressing roller 5 , a plurality of cooling rollers 6 , 7 , 8 , an unwinding roller, and two film laminating rollers 15 , 16 .

[0052] As another part of the optical plate manufacturing equipment 100 (in Figure 1 The extruder 2 may include a screw extruder connected to the extrusion die head 2 and a temperature control device coupled to the screw extruder, wherein the screw extruder is, for example, a twin-screw extruder or a single-screw extruder. During operation, the granular solid resin RE is supplied to the screw extruder and moves forward under the drive of the screw extruder, and during the movement, the temperature control device controls the temperature of the resin RE in the screw extruder, thereby making the resin RE molten. Since the screw extruder and the corresponding temperature control device are well known to those skilled in the art, they are not described in detail herein. Obviously, the resin RE can also be made molten by other means.

[0053] The extrusion die head 2 receives the resin RE in a molten state and supplies the resin RE in a molten state to the roller die 3 .

[0054] The roller mold 3 has a circumferential surface and a plurality of first microstructures 301 arranged on the circumferential surface 3a. The first microstructures 301 may be depressions recessed into the circumferential surface or protrusions protruding from the circumferential surface. In implementation, the device 100 may use the roller mold 3 to press out a second microstructure RE1 corresponding to the shape of the first microstructure 301 on the surface of the molten resin RE, and based on this, manufacture an optical plate 1 having a plurality of microstructures 101 on the surface, wherein the microstructure 101 of the optical plate 1 is defined by the second microstructure RE1. Figure 4 and Figure 5As shown, when the first microstructure 301 is concave, the second microstructure RE1 and the microstructure 101 of the optical plate 1 are convex corresponding to the shape of the concave; Figure 8 and Fig. 9 As shown, when the first microstructure 301 is a protrusion, the second microstructure RE1 and the microstructure 101 of the optical plate 1 are concave corresponding to the shape of the protrusion.

[0055] exist Figures 1 to 7 In the illustrated embodiments, the first microstructures 301 of the roller mold 3 are configured as depressions extending along the circumferential direction DR3 of the roller mold 3, and the first microstructures 301 are sequentially arranged in parallel with each other in the axial direction DR4 of the roller mold 3. More specifically, the first microstructures 301 are depressions extending in a circular ring shape around the entire circumference of the roller mold 3, and the cross section of the depressions can be an arch or a polygon, such as a triangle or a trapezoid. Figure 6 In the embodiment shown, the first microstructures 301 are arranged in a spaced relationship in the axial direction DR4 of the roller mold 3, so as to be used to manufacture the following Figure 7 The optical plate 1 shown, but in Figure 4 In the embodiment shown, the first microstructures 301 are arranged continuously in the axial direction DR4 of the roller mold 3, so as to be used for manufacturing the roller mold 3. Figure 5 The optical plate 1 is shown.

[0056] exist Figure 8 In another embodiment shown, the first microstructures 301 of the roller mold 3 are configured as protrusions extending along the circumferential direction DR3 of the roller mold 3, and these first microstructures 301 are arranged in parallel and spaced apart from each other in the axial direction DR4 of the roller mold 3, which can be used to manufacture the following Fig. 9 The optical plate 1 shown. More specifically, the first microstructure 301 is a protrusion extending in a circular shape around the entire circumference of the roller mold 3, and the cross section of the protrusion can be an arch or a polygon, for example, a triangle or a trapezoid.

[0057] In other embodiments, Fig.10 As shown, the first microstructures 301 of the roller mold 3 are configured as long strip-shaped depressions extending along the axial direction DR4 of the roller mold 3, and these first microstructures 301 are continuously arranged in parallel with each other in the circumferential direction DR3 of the roller mold 3. Such a roller mold 3 can also be used to manufacture Figure 5 The optical plate 1 shown. More specifically, Fig.10 In the embodiment, the first microstructure 301 extends over the entire length of the roller mold 3 and extends from one end surface of the roller mold 3 to the other end surface of the roller mold 3. Figure 4 and Figure 6 Similar to the embodiment, Fig.10The cross section of the first microstructure 301 can be polygonal or arched.

[0058] also, Fig.10 The first microstructures 301 on the middle roller mold 3 can also be arranged in parallel and spaced apart from each other in the circumferential direction DR3 of the roller mold 3, so as to be used for manufacturing the following example: Figure 7 The optical plate 1 is shown.

[0059] In some other embodiments, Fig.11 As shown, each first microstructure 301 of the roller mold 3 is constructed as island-shaped depressions separated from each other on the peripheral surface 3a of the roller mold 3. Such a roller mold 3 can be used to manufacture Fig.12 The optical plate 1 shown in FIG. 1 can be configured as a pyramid, a prism, a truncated sphere, a truncated cone, or the like. Fig.13 As shown, each first microstructure 301 of the roller mold 3 can also be constructed as island-shaped protrusions separated from each other on the peripheral surface 3a of the roller mold 3, so as to manufacture Fig.14 The optical plate 1 shown in FIG. 1 can be configured in the shape of a pyramid, a prism, a truncated sphere, a truncated cone or the like.

[0060] The first pressing roller 4 and the roller mold 3 form a first roller pair RP1. The first roller pair RP1 is configured to allow the molten resin RE to pass through a first space SP1 between the first pressing roller 4 and the roller mold 3, and to extrude the resin RE at the first space SP1 to extrude a second microstructure RE1 on one side surface of the resin RE, i.e., the first surface S1.

[0061] The second pressing roller 5 is arranged on the side of the roller mold 3 opposite to the first pressing roller 4, and the second pressing roller 5 forms a second roller pair RP2 with the roller mold 3. The second roller pair RP2 is configured to allow the resin RE drawn out through the first pressing roller 4 to pass through the second space SP2 between the second pressing roller 5 and the roller mold 3, and to support the resin RE at the second space SP2, so as to prolong the contact time between the resin RE and the roller mold 3, thereby optimizing the shape of the second microstructure RE1, thereby seeking to obtain a microstructure 101 of an ideal shape on the optical plate 1. In other embodiments, the second pressing roller 5 can be omitted, or a third pressing roller having the same function as the second pressing roller 5 can be added.

[0062] The plurality of cooling rollers 6, 7, 8 are arranged on the downstream side of the second roller pair RP2, and are configured to cool the resin RE to solidify the resin RE by contacting the other side surface of the resin RE on which the second microstructure RE1 is pressed, that is, the second surface S2, wherein the second surface S2 is the surface of the resin RE opposite to the second microstructure RE1. It can be understood that, compared with the scheme in which the cooling rollers 6, 7, 8 contact the first surface S1 of the resin RE to cool the resin RE, the cooling rollers 6, 7, 8 cool the resin RE by contacting the second surface S2 of the resin RE, which can prevent damage to the second microstructure RE1.

[0063] The protective film PF is wound on the protective film unwinding roller 14. During the operation, the protective film PF is unwound so that the protective film PF is supplied between the two film-laminating rollers 15 and 16. In addition, the resin RE cooled by the cooling rollers 6, 7, and 8 is also supplied between the two film-laminating rollers 15 and 16. Specifically, the protective film PF is supplied between the upper film-laminating roller 15 and the first surface S1 of the resin RE on which the second microstructure RE1 is pressed. Based on this, the protective film PF is attached to the first surface S1 of the resin RE on which the second microstructure RE1 is pressed, thereby protecting the first surface S1, especially the second microstructure RE1 on the first surface S1.

[0064] The inventor is using Figure 1 The device 100 shown and the Figure 1 When a similar optical plate manufacturing device is used to manufacture an optical plate 1, it is found that when the material, thickness DD, and microstructure period Pitch of the optical plate 1 remain unchanged, the height or depth Y of the microstructure 101 on the optical plate 1 and the depth or height X of the first microstructure 301 have the following mathematical relationship: X=k*Y+a. That is, the values ​​of k and a in the relationship X=k*Y+a are determined by the material, thickness DD, and period Pitch of the microstructure 101 on the optical plate 1. When the material, thickness DD, and microstructure period Pitch of the optical plate 1 remain unchanged, if the depth or height X of the first microstructure 301 is changed, the height or depth Y of the microstructure 101 on the optical plate 1 obtained will change accordingly according to the mathematical relationship X=k*Y+a.

[0065] Next, the inventors illustrate the above findings through several experimental examples.

[0066] First, the inventor selected Figure 4Four roller molds 3 with the configuration shown but different depths of the first microstructure 301 (a depression) respectively manufactured four optical plates 1, all of which were made of PMMA, with a thickness of 2.0 mm, and the periodic Pitch of the microstructure 101 on the four optical plates 1 was 200 μm. Since the technology of controlling the thickness and periodic Pitch of the microstructure of the manufactured optical plate 1 is well known, it will not be described in detail in this article.

[0067] The inventors obtained the following Table 1 by testing the height Y (average value) of the microstructures 101 (protrusions) on the four optical plates 1 .

[0068] Table 1: The data in Table 1 are linearly fitted, as shown in Fig.15 As shown. Fig.15 It can be obtained that X=2.72*Y-24, that is, k=2.72, a= -24. That is, for the optical plate 1 made of PMMA, with a thickness of 2.0 mm and a microstructure period Pitch of 200 μm, the height Y (average value) of the microstructure 101 on the optical plate 1 and the depth X of the first microstructure 301 on the roller mold 3 have a mathematical relationship of X=2.72*Y-24.

[0069] Furthermore, the inventors also selected Figure 4 Four other roller molds 3 with the same configuration as shown but with different depths of the first microstructure 301 (depression) were used to manufacture four other optical plates 1. The materials of the four optical plates 1 were all MS resin, the thickness was all 1.5 mm, and the period Pitch of the microstructure 101 on the four optical plates 1 was all 155 μm. The inventor obtained the following Table 2 by testing the height Y of the microstructure 101 (protrusion) on the four optical plates 1.

[0070] Table 2: The data in Table 2 are linearly fitted, as shown in Fig.16 As shown. Fig.16 It can be obtained that X=2.29*Y+ 33, that is, k=2.29, a=33. That is, for the optical plate 1 made of PMMA, with a thickness of 1.5 mm and a microstructure period Pitch of 155 μm, the height Y (average value) of the microstructure 101 on the optical plate 1 and the depth X of the first microstructure 301 on the roller mold 3 have a mathematical relationship of X=2.29*Y+ 33.

[0071] In addition, the inventor also selected Figure 4Three other roller molds 3 with the same configuration as shown but with different depths of the first microstructure 301 (depression) were used to manufacture three other optical plates 1. The materials of the three optical plates 1 were all PMMA, with a thickness of 0.7 mm, and the period Pitch of the microstructure 101 on the three optical plates 1 was 30 μm. The inventor obtained the following Table 3 by testing the height Y of the microstructure 101 (protrusion) on the four optical plates 1.

[0072] Table 3: The data in Table 3 are linearly fitted, as shown in Fig.17 As shown. Fig.17 It can be obtained that X=2.24*Y-6.5, that is, k=2.24, a= -6.5. That is, for the optical plate 1 made of PMMA, with a thickness of 0.7 mm and a microstructure period Pitch of 30 μm, the height Y (average value) of the microstructure 101 on the optical plate 1 and the depth X of the first microstructure 301 on the roller mold 3 have a mathematical relationship of X=2.24*Y-6.5.

[0073] In addition, the inventor also selected Figure 4 The other twelve roller molds 3 with the same configuration as shown but with different depths of the first microstructure 301 (which is a depression) respectively manufactured another twelve types of optical plates 1. These twelve types of optical plates 1 can be divided into four groups, with three types in each group. In addition, the three types of optical plates 1 in each group are made of the same material and have the same thickness and the same microstructure period Pitch (see the table below). The inventor obtained the following Table 4 by testing the height Y of the microstructure 101 on the four groups of twelve types of optical plates 1.

[0074] Table 4: It can be seen from Table 4 that when the thickness DD of the optical plate 1 is less than 0.7 mm, especially not more than 0.6 mm, when the material, thickness DD and microstructure period Pitch of the optical plate 1 remain unchanged, a=0 in the above relationship, and the height Y of the microstructure 101 on the optical plate 1 and the depth X of the first microstructure 301 on the roller mold 3 satisfy the mathematical relationship of X=k*Y. Specifically: For the optical plate 1 made of PMMA, with a thickness DD of 0.4 mm and a microstructure period Pitch of 30 μm, the height Y of the microstructure 101 on the optical plate 1 and the depth X of the first microstructure 301 on the roller mold 3 satisfy the relationship X=0.87*Y.

[0075] For the optical plate 1 made of PMMA, with a thickness DD of 0.5 mm and a microstructure period Pitch of 30 μm, the height Y of the microstructure 101 on the optical plate 1 and the depth X of the first microstructure 301 on the roller mold 3 satisfy the relationship X=0.83*Y.

[0076] For the optical plate 1 made of PMMA, with a thickness DD of 0.55 mm and a microstructure period Pitch of 30 μm, the height Y of the microstructure 101 on the optical plate 1 and the depth X of the first microstructure 301 on the roller mold 3 satisfy the relationship X=0.82*Y.

[0077] For the optical plate 1 made of PMMA, with a thickness DD of 0.6 mm and a microstructure period Pitch of 30 μm, the height Y of the microstructure 101 on the optical plate 1 and the depth X of the first microstructure 301 on the roller mold 3 satisfy the relationship X=0.79*Y.

[0078] From Tables 1 to 4 above, it can be seen intuitively that when using Figure 4 and Figure 6 When the roller mold 3 of this configuration is used to manufacture the optical plate 1, the height Y of the microstructure 101 on the manufactured optical plate 1 and the depth X of the first microstructure 301 on the roller mold 3 satisfy the mathematical relationship of X=k*Y+a, and when the material, thickness DD, and period Pitch of the microstructure 101 on the optical plate 1 are constant, the values ​​of k and a in the above relationship are constant. Therefore, when it is desired to manufacture an optical plate 1 with a microstructure 101 of a target height, the target height Y of the microstructure 101 can be substituted into the relationship X=k*Y+a, and the target depth X of the first microstructure 301 on the roller mold 3 that matches it can be determined, and then the roller mold 3 can be designed and manufactured according to the determined target depth X, and the manufactured roller mold 3 can be used to easily manufacture the optical plate 1 with the microstructure 101 of the above target height.

[0079] It is also necessary to point out that although the data in Tables 1 to 4 above are directly from Figure 4 and Figure 6 This configuration of the roller mold 3, but the inventor found that in the use of Figure 8 , Figure 10 to Figure 11 When the roller mold 3 shown is used to manufacture the optical plate 1, the depth or height X of the first microstructure 301 on the roller mold 3 and the height or depth Y of the microstructure 101 on the manufactured optical plate 1 also satisfy the relationship X=k*Y+a, and when the thickness of the optical plate 1 is less than 0.7 mm, especially not more than 0.6 mm, a=0. In addition, when the manufactured optical plate 1 is not PMMA resin RE or MS resin RE but other materials, such as PC resin RE, the relationship X=k*Y+a is also satisfied.

[0080] Based on the above explanation and Figures 1 to 14 The embodiment of the present application proposes a design method 200 for a roller mold 3. The roller mold 3 to be designed has a peripheral surface 3a and a plurality of first microstructures 301 arranged on the peripheral surface 3a, and is used to extrude a second microstructure RE1 corresponding to the shape of the first microstructure 301 on the surface of the molten resin RE, and based on this, a target optical plate 1 having a plurality of target microstructures 101 on the surface is manufactured, wherein one of the first microstructure 301 and the second microstructure RE1 is a protrusion and the other is a depression, and the target microstructure 101 is defined by the second microstructure RE1. The design method 200 utilizes the above discovery of the inventor. Fig.18 As shown, the design method 200 includes: S181, determining the value of k and the value of a according to the material of the target optical plate 1, the thickness of the target optical plate 1 and the period of the target microstructure 101; S182 , determining the depth or height X1 of the first microstructure 301 based on the relationship X1=k*Y1+a, wherein Y1 is the height or depth of the target microstructure 101 .

[0081] In some embodiments, Fig.19 As shown, the aforementioned step S182 may specifically include: S191, providing a second resin corresponding to the material of the target optical plate 1, a second roller mold having a second peripheral surface and a plurality of third microstructures disposed on the second peripheral surface, and a third roller mold having a third peripheral surface and a plurality of fourth microstructures disposed on the third peripheral surface, wherein the third microstructure, the fourth microstructure and the first microstructure 301 are all convex or concave, the period of the third microstructure and the period of the fourth microstructure correspond to the period Pitch of the target microstructure 101, the depth or height of the third microstructure is X2, the depth or height of the fourth microstructure is X3, and X2≠X3; S192, using a second roller mold to extrude a fifth microstructure corresponding to the shape of the third microstructure on the surface of the second resin in a molten state, and based on this, a second optical plate having a plurality of sixth microstructures on the surface is manufactured, wherein the sixth microstructure is defined by the fifth microstructure, and the second optical plate has the same thickness DD as the target optical plate 1; S193, using a third roller mold to extrude a seventh microstructure corresponding to the shape of the fourth microstructure on the surface of the second resin in a molten state, and based on this, a third optical plate having a plurality of eighth microstructures on the surface is manufactured, wherein the eighth microstructure is defined by the seventh microstructure, and the third optical plate has the same thickness DD as the target optical plate 1; S194, measuring the height or depth of the seventh microstructure to be Y2, and measuring the height or depth of the eighth microstructure to be Y3; S195, based on the relationship X2=k*Y2+a and X3=k*Y3+a, determine the value of k and the value of a.

[0082] As mentioned above, the inventors have found that when the roller mold 3 is used to manufacture the optical plate 1, the height Y of the microstructure 101 on the manufactured optical plate 1 and the depth X of the first microstructure 301 on the roller mold 3 satisfy the mathematical relationship of X=k*Y+a, and when the material, thickness, and period Pitch of the microstructure 101 on the optical plate 1 are constant, the values ​​of k and a in the relationship are fixed. Therefore, if the values ​​of k and a in the relationship are known, the depth or height X1 of the first microstructure 301 on the roller mold 3 used to manufacture the target optical plate 1 can be determined according to the relationship X1=k*Y1+a, based on the height or depth Y1 (known quantity) of the target microstructure 101 on the target optical plate 1 to be manufactured. Based on this idea, the embodiment of the present application provides a second roller mold and a third roller mold corresponding to the target microstructure period Pitch on the target optical plate 1 through well-known techniques (for example, the period of the third microstructure on the second roller mold is designed to correspond to the period of the target microstructure 101 on the target optical plate 1, and the period of the fourth microstructure on the third roller mold is also designed to correspond to the period of the target microstructure 101 on the target optical plate 1), and provides a second resin corresponding to the material of the target optical plate. At the same time, the third microstructure on the second roller mold and the fourth microstructure on the third roller mold are designed to be different in depth or height, and then through well-known techniques (for example, by adjusting The gap between the roller mold and the first pressing roller 4 and the second pressing roller 5), the second roller mold and the third roller mold are used to manufacture the second optical plate and the third optical plate with the same thickness (and the same microstructure period Pitch) as the target optical plate 1, and then the height or depth of the sixth microstructure on the second optical plate is measured as Y2 and the height or depth of the eighth microstructure on the third optical plate is measured as Y3, and then combined with the known depth or height of the third microstructure on the second roller mold as X2 and the known depth or height of the fourth microstructure on the third roller mold as X3, the values ​​of k and a can be calculated according to the equation group composed of the relationship X2=k*Y2+a and X3=k*Y3+a.

[0083] It is also mentioned above that when the thickness of the optical plate 1 is less than 0.7 mm, especially not more than 0.6 mm, the value of a in the relationship X=k*Y+a is 0, that is, the height Y of the microstructure 101 on the optical plate 1 and the depth X of the first microstructure 301 on the roller mold 3 satisfy the mathematical relationship X=k*Y. Therefore, in the design method 200, if the thickness of the target optical plate 1 is less than 0.7 mm, especially not more than 0.6 mm, the value of a in X1=k*Y1+a can be directly determined as 0, and the value of k in X1=k*Y1 can be further determined by relevant means. Specifically, Fig. 20 As shown, the aforementioned step S182 may include the following designs: S201, if the thickness of the target optical plate 1 is less than 0.7 mm, especially not more than 0.6 mm, the value of a in X1=k*Y1+a is determined to be 0; S202, providing a third resin corresponding to the material of the target optical plate 1, and a fourth roller mold having a fourth peripheral surface and a plurality of ninth microstructures disposed on the fourth peripheral surface, wherein the ninth microstructure and the first microstructure 301 are both convex or concave, the period of the ninth microstructure corresponds to the period of the target microstructure 101, and the depth or height of the ninth microstructure is X4; S203, using a fourth roller mold to extrude a tenth microstructure corresponding to the shape of the ninth microstructure on the surface of the molten third resin, and based on this, a fourth optical plate having a plurality of eleventh microstructures on the surface is manufactured, wherein the eleventh microstructure is defined by the tenth microstructure, and the fourth optical plate corresponds to the thickness DD of the target optical plate 1; S204, measuring the height or depth of the eleventh microstructure as Y4; S205, based on the relationship X4=k*Y4, determine the value of k.

[0084] Thus, the values ​​of a and k in X1=k*Y1+a are known.

[0085] See also Fig.21 The present application also provides a method 300 for manufacturing an optical plate 1, the method 300 comprising: S211, designing a roller mold 3 according to the aforementioned design method 200; S212, manufacturing the designed roller mold 3; S213 , manufacturing an optical plate 1 (target optical plate) using the roller mold 3 manufactured in step S212 .

[0086] Combined with the previous Figure 1 In some embodiments, as Fig. 22 As shown, step S213 can be used Figure 1The optical plate manufacturing device 100 is performed and may specifically include: S221, making the resin RE into a molten state; S222, using the cooperation between the roller mold 3 and the first pressing roller 4 and the second pressing roller 5, a second microstructure RE1 is pressed out on the first surface S1 of the resin RE in a molten state; S223, cooling the resin RE that has been pressed out to form the second microstructure RE1, so that the resin RE becomes a solidified state; S224, attaching a protective film PF on the first surface S1 of the cured resin RE corresponding to the second microstructure RE1; S225 , cutting the resin RE to which the protective film PF is attached, thereby obtaining a plurality of optical plates 1 .

[0087] Combined with the above introduction and review Figure 5 , Figure 7 , Figure 8 , Fig.12 and Fig.14 The embodiment of the present application further provides an optical plate 1, which is manufactured by the manufacturing method 300. The optical plate 1 has a first main surface 1a and a second main surface 1b arranged opposite to each other in the thickness direction thereof, and a plurality of microstructures 101 formed by a roller mold 3 are formed on the first main surface 1a.

[0088] exist Figure 5 , Figure 7 and Figure 8 In the embodiment, the microstructure 101 on the optical plate 1 is in the shape of a long strip extending along the first direction DR1, and a plurality of microstructures 101 are arranged in sequence in the second direction DR2 perpendicular to the first direction DR1, and the first main surface 1a is defined by the first direction DR1 and the second direction DR2, that is, the first main surface 1a extends in the first direction DR1 and the second direction DR2 perpendicular to each other. The optical plate 1 can be made into a light guide plate or a light diffusion plate, for example.

[0089] exist Fig.12 In the embodiment, the microstructures 101 on the optical plate 1 are configured as island-shaped protrusions separated from each other on the first major surface 1 a.

[0090] exist Fig.14 In the embodiment, the microstructures 101 on the optical plate 1 are configured as island-shaped depressions separated from each other on the first major surface 1 a.

Claims

1. A method for designing a roller mold, wherein the roller mold has a peripheral surface and a plurality of first microstructures arranged on the peripheral surface, and is used to extrude a second microstructure corresponding to the shape of the first microstructure on the surface of a molten resin, and based on this, a target optical plate having a plurality of target microstructures on the surface is manufactured, wherein: One of the first microstructure and the second microstructure is a protrusion, and the other is a depression, and the target microstructure is defined by the second microstructure, wherein the design method comprises: Determine the value of k and the value of a according to the material of the target optical plate, the thickness of the target optical plate and the period of the target microstructure; Based on the relationship X1=k*Y1+a, the depth or height X1 of the first microstructure is determined, wherein Y1 is the height or depth of the target microstructure.

2. The design method according to claim 1, characterized in that: The method of determining the value of k and the value of a according to the material of the target optical plate, the thickness of the target optical plate and the period of the target microstructure includes: Providing a second resin corresponding to the material of the target optical plate, a second roller mold having a second peripheral surface and a plurality of third microstructures disposed on the second peripheral surface, and a third roller mold having a third peripheral surface and a plurality of fourth microstructures disposed on the third peripheral surface, wherein the third microstructure, the fourth microstructure and the first microstructure are all the protrusions or are all the depressions, and the period of the third microstructure and the period of the fourth microstructure correspond to the period of the target microstructure respectively, the depth or height of the third microstructure is X2, the depth or height of the fourth microstructure is X3, and X2≠X3; Using the second roller mold, a fifth microstructure corresponding to the shape of the third microstructure is pressed out on the surface of the second resin in a molten state, and based on this, a second optical plate having a plurality of sixth microstructures on the surface is manufactured, wherein the sixth microstructure is defined by the fifth microstructure, and the second optical plate has the same thickness as the target optical plate; Using the third roller mold, a seventh microstructure corresponding to the shape of the fourth microstructure is pressed out on the surface of the second resin in a molten state, and based on this, a third optical plate having a plurality of eighth microstructures on the surface is manufactured, wherein the eighth microstructure is defined by the seventh microstructure, and the third optical plate has the same thickness as the target optical plate; The height or depth of the sixth microstructure is measured to be Y2, and the height or depth of the eighth microstructure is measured to be Y3; Based on the relationships X2=k*Y2+a and X3=k*Y3+a, determine the value of k and the value of a.

3. The design method according to claim 1, characterized in that: The method of determining the value of k and the value of a according to the material of the target optical plate, the thickness of the target optical plate and the period of the target microstructure includes: If the thickness of the target optical plate is less than 0.7 mm, the value of a is determined to be 0.

4. The design method according to claim 3, characterized in that: If the thickness of the target optical plate is less than 0.7 mm, the value of a is determined to be 0, including: If the thickness of the target optical plate is less than 0.6 mm, the value of a is determined to be 0.

5. The design method according to claim 3 or 4, characterized in that: The method of determining the value of k and the value of a according to the material of the target optical plate, the thickness of the target optical plate and the period of the target microstructure includes: Providing a third resin corresponding to the material of the target optical plate, and a fourth roller mold having a fourth peripheral surface and a plurality of ninth microstructures disposed on the fourth peripheral surface, wherein the ninth microstructure and the first microstructure are both the protrusions or both are the depressions, and the period of the ninth microstructure corresponds to the period of the target microstructure, and the depth or height of the ninth microstructure is X4; Using the fourth roller mold, a tenth microstructure corresponding to the shape of the ninth microstructure is pressed out on the surface of the third resin in a molten state, and based on this, a fourth optical plate having a plurality of eleventh microstructures on the surface is manufactured, wherein the eleventh microstructure is defined by the tenth microstructure, and the fourth optical plate has the same thickness as the target optical plate; The height or depth of the eleventh microstructure is measured to be Y4; Based on the relationship X4=k*Y4, determine the value of k.

6. The design method according to any one of claims 1 to 4, characterized in that: The material of the target optical plate is selected from PMMA resin, MS resin or PC resin.

7. The design method according to claim 1, characterized in that: The first microstructure is configured to extend along the circumferential direction of the roller mold, and the plurality of first microstructures are arranged in sequence in the axial direction of the roller mold; or, The first microstructure is configured to extend along the axial direction of the roller mold, and the plurality of first microstructures are sequentially arranged in the circumferential direction of the roller mold; or, The plurality of first microstructures are configured as island-type depressions or island-type protrusions spaced apart from each other on the peripheral surface of the roller mold.

8. A method for manufacturing a target optical plate, characterized in that: include: Designing a roller mold according to the design method according to any one of claims 1 to 7; manufacturing the roller mold; The target optical plate is manufactured using the roller mold.

9. The manufacturing method according to claim 8, characterized in that: The method of manufacturing the target optical plate by using the roller mold comprises: making the resin into a molten state; Using the cooperation between the roller mold and the pressing roller, the second microstructure is pressed out on the surface of the resin in a molten state; Cooling the resin with the second microstructure pressed out, so that the resin becomes a solidified state; Attaching a protective film to the surface of the cured resin on which the second microstructure is pressed; The resin to which the protective film is attached is cut.

10. The manufacturing method according to claim 8 or 9, characterized in that: The method of manufacturing the target optical plate by using the roller mold comprises: The target optical plate is manufactured using an optical plate manufacturing device including the roller mold, wherein the optical plate manufacturing device includes: a first pressing roller, forming a first roller pair with the roller mold, wherein the first roller pair is configured to allow molten resin to pass through a first space between the first pressing roller and the roller mold, and to extrude the resin in the first space to extrude the second microstructure on a surface of the resin; A cooling roller is disposed on the downstream side of the roller mold and is configured to cool the resin by contacting the other surface of the resin on which the second microstructure is pressed, wherein the other surface is a surface of the resin opposite to the second microstructure.

11. The manufacturing method according to claim 10, characterized in that: The optical plate manufacturing equipment also includes: A second pressing roller is arranged on the side of the roller mold opposite to the first pressing roller and on the upstream side of the cooling roller, and forms a second roller pair with the roller mold. The second roller pair is constructed to allow the resin drawn out through the first pressing roller pair to pass through a second space between the second pressing roller and the roller mold, and to support the resin in the second space to optimize the shape of the second microstructure.

12. A target optical plate, characterized in that: The target optical plate is manufactured by the manufacturing method according to any one of claims 8 to 11.

13. The target optical plate according to claim 12, characterized in that: The target optical plate has a first main surface and a second main surface that are oppositely disposed in a thickness direction thereof, and the plurality of target microstructures are formed on the first main surface.

14. The target optical plate according to claim 13, characterized in that: The target microstructure is configured as a strip extending along a first direction, and the plurality of target microstructures are sequentially arranged in a second direction intersecting the first direction, and the first main surface is defined by the first direction and the second direction; or, The plurality of target microstructures are configured as island-shaped protrusions or island-shaped depressions spaced apart from each other on the first major surface.

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