TW594224B - Light-guiding structure of light-guiding device and manufacturing method thereof - Google Patents

Abstract

A light-guiding structure of light-guiding device and manufacturing method thereof are disclosed, which is to dispose an etched substrate on a tilted stage for heating. When the photoresist layer is softened by the heat, it will flow downward due to the slope of the tilted stage, so as to form a asymmetric deformation structure. The top surface of the deformed structure forms a slant plane more steeply, and a slant plane less steeply than the said slant plane.

Description

594224 _ Case No. 91106262_ Modification of the month and month _ V. Description of the invention (1) [Technical Field] The present invention relates to a light guide structure of a light guide element and a method for manufacturing the same, especially when a light guide element is filled with plastic. The light guide structure is completely filled to ensure that the outer surface of the protruding portion of the light guide element is complete, and the angle formed by the outer surface of the protruding portion can guide the light emitted from the light source to a predetermined direction, thereby improving the light guide effect. [Previous technology] Please refer to FIG. 4 to explain the manufacturing method of the conventional light guide element, which is coated with a positive photoresist layer 7 2 on a substrate 7 1 and then on the substrate 7 1 A mask 7 3 is covered above the surface for exposure under the UV light source 7 9. The mask 7 3 has a plurality of holes 7 3 1, so that the photoresist layer forms a majority of exposed portions 7 2 1 and an unexposed portion 7 2 2. The exposed substrate 7 1 is immersed in a developing solution 7 4 so that the unexposed portion 7 2 2 is etched away. Then, the substrate 7 1 is taken out of the developing solution 7 4 for heat treatment to expose the exposed portion. The top of the portion 7 2 1 is softened by heat, and a deformed structure 7 2 3 is formed, which is almost circular and symmetrical. After depositing a metal layer 75 on the top surface of the photoresist layer 72, the substrate 7 1 is separated from the metal layer 75, and the bottom surface of the metal layer 75 is formed with a concave surface 7 5 1 which is complementary to the deformed structure. The layer 7 5 is made into a mold core, which is placed in a mold 76 and injected with plastic. After the plastic is hardened and opened, a light guide element 7 7 is obtained. However, after the photoresist layer 7 2 is softened by heat, it forms a uniform and symmetrical deformation structure 7 2 3, so that the concave surface 7 5 1 of the metal layer 7 5 is also a uniform and symmetrical shape. Therefore, when the plastic is injected, Air is easy

Page 5 594224 _Case No. 91106262_ Years and Months Revisions_ 5. Description of the Invention (2) Concentrated on the deepest part A and difficult to discharge, resulting in the plastic cannot be completely filled, so that the convex portion on the surface of the light guide element will have The undesired concave point 7 7 1 causes the light emitted by the light source 7 8 to hit the inner surface of the convex portion, and is affected by the inner surface of the irregular concave point, so that the light cannot be directed in a predetermined direction (Figure 5), so that The light element cannot effectively achieve its light guiding effect. In addition, as shown in FIG. 5, the arc surface formed by the photoresist layer 72 after being softened by heat is limited (that is, the angle r of the top surface of the light guide element 7 7 is too large), so the direction after light reflection is easily deviated. . Therefore, it is necessary to improve the above problems. [Objective and Effect] The main purpose of the present invention is to solve the above problems and provide a light guide structure of a light guide element and a manufacturing method thereof. By placing a glass substrate having a photoresist layer on an inclined table, When the photoresist layer is softened due to heat, it will flow slightly downward due to the inclined shape of the inclined table, so that the light guide element placed afterwards has most inclined convex portions, and is formed by the outer side of the convex portion The included angle allows the light emitted by the light source to be guided in a predetermined direction by the light guide element, so that when the light is reflected, it will not form an improper and deflected reflection and concentrate the light guide direction. Still another object of the present invention is to provide a light guide structure of a light guide element and a manufacturing method thereof. By placing a glass substrate having a photoresist layer on an inclined table, the photoresist layer will soften when heated due to heat. Due to the inclined shape of the inclined table, it flows slightly downward, so that the concave surface of the metal layer microstructure surface is asymmetrical. Therefore, when the plastic is injected, the plastic will force the air to flow out to the slower side of the concave surface. Make the outer side of the projection of the light guide element complete, and

594224 _ Case No. 91106262_ 年月 日 __ V. Description of the invention (3) It can form a smooth surface with a large arc, and ensure the light guide effect. [Technical content] The present invention provides a method for manufacturing a light-guiding structure of a light-guiding element, which comprises coating a photoresist layer on the top surface of a substrate, and placing the substrate under a photomask. The photomask has A plurality of holes of a predetermined shape are exposed by a UV light source provided above the mask, so that the UV light emitted by the UV light source passes through the holes of the mask and is irradiated on the photoresist layer, so that the photoresist layer Form most exposed portions and most unexposed portions, and then immerse the substrate and the photoresist layer in a developing solution, so that most exposed or unexposed portions of the photoresist layer are etched to form a concave portion, respectively. The etched portions respectively form a convex portion that is more convex than the concave portion; and then the etched photoresist layer and the substrate are placed in a heating box and heated, so that most of the remaining portions of the photoresist layer are softened by heat and formed separately. A deformed structure, and a metal layer is electroformed on the side of the photoresist layer away from the base material, so that the metal layer forms a microstructure surface that is complementary to most of the deformed structure of the photoresist layer. And inject plastic, while plastic is hard After the mold is opened, the light guide element is formed. The light guide element has a light guide surface that is complementary to the microstructure surface. The light guide element is characterized in that when the substrate is heated, the substrate is placed on an inclined table. When the tops of the majority of the retained parts are softened, they will flow downwards by gravity due to the inclination of the inclined platform, so that the deformed structure has an asymmetrical shape, and the deformed structure has a most convex point. The bumps extend obliquely to the surroundings, and the tangents on the top surface of the deformed structure do not overlap each other. The side of the most bumped point forms a steeper steep surface, and the side opposite to the steep surface is formed by downward flow. A relatively flat

594224 _Case No. 91106262_ Years and months Amendment _ V. Description of the invention (4) The angle between the tangent of the steep surface and the top surface of the substrate is greater than the central angle between the tangent of the surface and the top surface of the substrate. The above and other objects and advantages of the present invention can be easily understood from the detailed description and accompanying drawings of the selected embodiments below. Of course, the present invention allows some differences in the arrangement or arrangement of other parts, but the selected embodiment is described in detail in this specification and its structure is shown in the drawings. [Detailed description of the embodiment] Please refer to FIG. 1 to FIG. 3, which are the structure of the embodiment of the present invention, which is used for illustration only, and is not subject to such structure in patent applications. limit. The present invention relates to a light guiding structure of a light guiding element and a manufacturing method thereof. The manufacturing method is performed by: coating a photoresist: coating a photoresist layer 2 on a glass substrate 1 top surface 1, the photoresist layer 2 The viscosity is between 100 and 1600 centipoise (cp s), and the coating method can be a method familiar to those skilled in the art, such as spraying, rollers, etc. The photoresist layer 2 can be positive Type photoresist (such as C lariant Α ζ ρ462 Ό) or negative type photoresist. Exposure: The glass substrate 1 coated with the photoresist layer 2 is placed under a photomask 3 1. The photomask 3 1 has a plurality of holes 3 1 1 of a predetermined shape.

A U V light source 3 2 is provided above the cover 31, so that the photoresist layer 2 is irradiated by the U V light source 32 to form most exposed portions 21 and most unexposed portions 22. Etching: dipping the photoresist layer 2 and glass substrate 1 after exposure

594224 _Case No. 91106262_ Revised Year_ of the Invention_5. Description of the Invention (5) In the etched groove 3 3, a developing solution 3 4 is stored in the etched groove 3 3 to etch the photoresist layer 2. Material 1 is coated with a positive-type photoresist. Therefore, the exposed portion 2 1 exposed to the UV light source 3 2 will not be etched, and a reserved portion 2 3 is formed, and the unexposed portion is not exposed to the UV light source 3 2. 2 2 is etched to make it thinner downward to form a recessed portion 2 4 which is recessed more than the remaining portion 2 3. Heating: The etched photoresist layer 2 is placed on a tilting table 4, which is arranged in a heating box 81, and a driving motor 4 1 is combined at the bottom end of the tilting table 4 Driven by the driving motor 41, the photoresist layer 2 and the glass substrate are heated to 110 ° -250 ° C by a heating box 81. The angle between the top surface 41 of the inclined table 4 and the horizontal plane is 1 ° ~ 40 °. When the top of the retaining portion 23 is softened by heating with the inclined form of the inclined platform 4, the softened top will flow downward due to gravity, forming an asymmetrical shape. Deformed structure 25, the deformed structure 25 has a most convex point 2 5 1, and is inclined to extend from the most convex point to the surroundings, and the tangents on the top surface of the deformed structure 25 do not overlap each other, the most convex point 2 5 1 —A relatively steep surface 2 1 1 is formed on one side, and a gentle surface 2 1 2 is formed as a result of downward flow on one side opposite to the steep surface 2 1 1. The steep surface 2 1 1 is gentle The included angle between the tangent of the surface 2 12 and the top surface of the glass substrate 1 is an included angle α and an included angle / 3, respectively, wherein the included angle α is greater than the included angle / 5. Electroforming: A metal layer 5 of a predetermined thickness is electroformed on the top surface of the photoresist layer 2 having a large number of deformed structures. Separation: the metal layer 5 is separated from the glass substrate 1 and separated from the metal layer

594224 _Case No. 91106262_ 年月 日 __ V. Description of the invention (6) 5 A microstructured surface 5 1 is formed near one surface of the base material 1, and the microstructured surface 5 1 has a concave surface 5 1 which is mostly complementary to the deformed structure. 1, and then combine the metal layer 5 with a mold steel 9 to form a mold core 90. Molding: The mold core 90 is placed in a mold 3 5, and a space 3 5 1 is defined between the mold core 90 and the mold 3 5, and then a plastic 60 is injected into the space 3 5 1 to make the plastic 6 0 completely fills the entire space 3 5 1. After the plastic 60 is hardened, the mold is opened to form the hardened plastic 60 to form a light guide element 6. The top surface of the light guide element 6 forms a light guide surface 6 1 corresponding to the microstructure surface 51, and the light guide surface 6 1 has a plurality of convex portions 6 1 1 corresponding to the microstructure surface 51. The outer mask of the part 6 1 1 has a most convex point 6 1 5, and the oblique extension from the most convex point to the surroundings, and the tangent lines on the outer surface of the protruding part 6 1 1 do not overlap each other, the most convex point 6 1 A side of the steep surface 6 1 2 is formed on the 5 side, and a gentle surface 6 1 3 is formed on the side opposite the steep surface 6 1 2 due to the downward flow. The tangent and guide of the steep surface 6 1 2 The included angle of the smooth surface 6 1 is an included angle α, and the tangent of the slow surface 6 1 3 and the inflammation angle of the light guide surface 61 is an included angle / ?, the included angle / 3 is greater than the included angle α, and the protruding portion 6 1 1 The tangents on the outside surface do not overlap each other. It can be known from the above description that the present invention, by placing the glass substrate 1 having the photoresist layer 2 on the inclined table 4, most of the exposed portions 2 1 of the photoresist layer 2 are softened by heat due to the The oblique shape and the downward flow of gravity cause the deformed structure 2 5 to form a steep surface 2 1 1 and a gentle surface 2 1 2 at both ends of the top surface. Therefore, the concave surface 5 1 1 of the metal layer 5 is also formed on one side. Steep, asymmetrical shape on the other side, so when the plastic is injected into the mold 35, the air will be forced to flow out towards the slower side, so that the plastic can finish

Page 10 594224 _Case No. 91106262_ Year Month Date__ V. Description of the invention (7) The full filling space 3 5 1 enables the outer side of the protruding portion 6 1 1 of the light guide element 6 to be completed. In addition, as shown in FIG. 3, since the outer surface of the protruding portion 6 1 1 of the light guide element 6 has no uneven structure, and by forming the gentle surface 6 1 3, the outer surface of the protruding portion 6 1 1 The radian of the side becomes larger, that is, the characteristic that the included angle of the slow surface 6 1 3/3 is smaller than the included angle r of the top surface of the prior art light guide element 7 7 enables the light guide element 6 of the present invention to direct the light emitted by the light source 8 2 to a predetermined Direction without the problem that the light is easily deflected as described in the prior art. It should be particularly reminded that the photoresist layer of the present invention is not limited to using a positive type photoresist, but a negative type photoresist may also be used. When a glass substrate coated with a negative type photoresist is placed under a photomask and exposed, When immersed in a specific developer, most of the exposed parts will be engraved with money, while the unexposed parts will not be engraved with money. In summary, in the present invention, by placing a glass substrate with a photoresist layer on an inclined table, when the photoresist layer is softened by heat, it will flow slightly downward due to the inclined form of the inclined table, thereby making all The concave surface of the microstructure surface of the prepared metal layer is asymmetrical, so when plastic is injected, the plastic will force the air to flow out to the slower side of the concave surface, so that the outer side of the convex portion of the light guide element can be completed, and The shape of the slow surface allows the light guide element to effectively guide light to a predetermined direction, and reduces the light loss caused by light inside the light guide plate, ensuring the light guide effect. Of course, there are still many examples of the present invention, in which only the details have changed

Page 11 594224 _Case No. 91106262_Year Month Date _ ^ _ V. Description of the Invention (8) The difference of the second embodiment of the present invention is that heating: place the etched glass substrate on a non-rotating glass substrate Tilt the table to achieve the effect described in the first embodiment. The disclosure of the embodiments described above is used to illustrate the present invention, and is not intended to limit the present invention. Therefore, any change in the value or replacement of equivalent components should still belong to the scope of the present invention. From the above detailed description, those skilled in the art can understand that the present invention can indeed achieve the aforementioned purpose, and it has indeed complied with the provisions of the Patent Law, and filed a patent application.

Page 12 594224 Case No. 91106262 Revised diagram Brief description Briefly, Figure 1 is a schematic flow chart of the light guide element manufacturing method of the present invention. Figure 2a is an enlarged schematic view of the projection of the light guide element of the present invention. Figure 2b is Top view of the projection of the light guide element of the present invention. FIG. 3 illustrates a case where the light guide element of the present invention has a good light guide effect. FIG. 4 illustrates a conventional light guide element. FIG. 5 illustrates a conventional light guide element, which causes light. Biased [Pictures and Numbers] (conventional part) Substrate 7 1 Photomask 7 Photoresist layer 7 2 Hole 7 Exposed part 7 2 1 Unexposed part of developer 7 2 2 Deformed structure of metal layer 7 2 3 Concave surface 7 Manufacturing method The process is not intended to be a situation where the light cannot be guided well 3 mold 7 6 3 1 light guide element 7 7 7 4 pit 7 7 1 7 5 light source 7 8 5 1 UV light source 7 9 (part of the present invention) substrate 1 Top surface 1 1 Photoresist layer 2 Exposed portion 2 1 Steep surface 2 1 1 Slow surface 2 1 2 Unexposed portion 2 2 Mask 3 1 Hole 3 1 1 UV light source 3 2 Etching tank 3 3 Developer 3 4Mold 3 5 Space 3 5 1 Plastic 6 0 Light guide element 6 Light guide surface 6 1 Projection 6 1 1 Steep surface 6 1 2 Slow surface 6 1 3 Most convex point 6 1 5

Page 13 594224 Case No. 91106262 Brief description of the revised diagram Reserved part 2 3 Inclined table 4 Concave part 2 4 Deformed structure of drive motor 2 5 Metal layer 5 Most convex point 2 5 1 Microstructure concave surface 5 1 Heating box 8 1 Light source 8 2 Mould steel 9 Mould core 9〇

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Claims (1)

594224; _Case No. 91106262_Amended in January of the year. 6. The angle between the scope of the patent application and the top surface of the substrate is greater than the angle between the tangent of the gentle surface and the top surface of the substrate. The manufacturing method of the light guide structure of the optical element, wherein the angle between the inclined table and the horizontal plane is between 1 degree and .40 degrees. 3. The manufacturing method of the light guide structure of the light guide element according to item 1 of the scope of the patent application, wherein the viscosity of the photoresist layer is between 100 and 600 centipoise, and the substrate and the photoresist layer Heating to 110 ° C ~ 250 ° C to soften the top of the majority of the retained parts. 4 According to the manufacturing method of the light guide structure of the light guide element described in item 1 of the patent application scope, wherein the tilt The table is combined with a driving motor, and the tilting table is rotated by the driving motor. 5 · A light-guiding structure made by any one of the methods of applying for a patent in the range of items 1 to 4, the light-guiding structure has a light-guiding surface, and the light-guiding surface has most asymmetric projections The protruding portion has a most protruding point, which extends obliquely from the most protruding point to the surroundings, and the tangent lines on the outer surface of the protruding portion do not overlap each other, and a steeper steepness is formed on one side of the most protruding point. Surface, an angle α is formed between the tangent of the steep surface and the light guide surface; a gentle surface with a steeper surface is formed opposite to one side of the steep surface, and an angle is formed between the tangent of the slow surface and the light guide surface The angle / 5 is greater than the angle of inflammation α. Page 16