TW201710054A - Manufacturing method of optical microstructure, processing machine table and its light guide plate mold having excellent structural strength for prolonging service life of the convex portion as the mold - Google Patents

Abstract

This invention provides a manufacturing method of an optical microstructure, a processing machine table and its light guide plate mold. The manufacturing method comprises the following steps: irradiating a base material with a melting point temperature by using a laser beam and making a processing temperature of the laser beam conform to a condition of C1 ≤ C2 ≤ (1.1×X), so that when the laser beam is irradiated onto the base material, the base material is melted and cooled to form at least one convex portion on the surface of the base material and a recessed portion on the peripheral side of the convex portion. By controlling the processing temperature, convex portion can be formed on the base material through laser processing, and further utilizing the base material as a manufacturing mold of a light guide plate. The base material is wrapped around the outer side of a roller to emboss the light guide plate so that the surface of the light guide plate corresponding to the convex portion forms a recessed microstructure. The convex portion is not easily cracked during the embossing process, and has excellent structural strength for prolonging service life of the convex portion as the mold.

Description

Optical microstructure manufacturing method, processing machine and light guide plate mold thereof

The invention relates to the field of light guide plate processing, in particular to the field of processing light guide plates for manufacturing optical microstructures.

The light guide plate is a component of the backlight module for guiding light to form a uniform light output, and the light incident from the light guide surface of the light guide plate is transmitted to the distal end of the light guide plate by using the principle of total reflection, and the light guide plate is utilized. The complex optical microstructure destroys total reflection to adjust the amount of light and the uniformity of light emission to form a uniform surface source.

Traditionally, the way to form an optical microstructure on a light guide plate is a multi-printing method. The optical microstructure pattern is designed to be printed on the light guide plate by using a high-scattering light source material to form a dot, and the dots are destroyed by the full reflection of the light to control the light. However, the dot structure formed on the light guide plate by printing is difficult to control because the viscosity of the printing ink is easily affected by environmental factors, so that the uniformity of the dot structure and the individual dimensions are difficult to control, thereby reducing the yield of the product and consuming the overall process time. .

In view of the inconvenience of printing optical microstructures, subsequent fabrication methods for a variety of non-printed optical microstructures have been derived. For the purpose of forming the light guide plate into the optical microstructure together, the light guide plate mold can be machined, or the optical microstructure pattern can be formed on the surface of the mold by etching. Machining, for example, directly cutting the desired optical microstructure pattern through the cutter to form an optical microstructure pattern corresponding to the light guide plate formed by the mold core And has multiple outlets. However, with the tool cutting method, the minimum size of the optical microstructure is limited by the tool and cannot be extremely miniaturized, which is inconsistent with the demand of the current market, and the microstructure of the process is extremely time consuming and easy to have errors. The etching method requires a complicated process such as coating, exposure and electroforming, and also increases the manufacturing cost and difficulty of the mold.

Therefore, in order to solve the problem of the efficiency of manufacturing the optical microstructure of the mold core, the light guide plate structure of the Republic of China Patent Application No. 93113610 and the manufacturing method thereof disclose a method for manufacturing a light guide plate, the steps of which include providing a substrate; using at least one laser Irradiating at different positions on the substrate to form a wrinkle dot at each position to form a mold core; and forming a light guide plate by using the mold core. The method utilizes laser processing to form a wrinkle dot on the mold core, and then uses the mold to form the light guide plate by injection, hot pressing, casting, die casting or pouring. In addition to directly forming the light guide plate by the above method, there is also a method of using the roller to imprint the light guide plate to form an optical microstructure on the light guide plate, which is similar to the above method, except that the substrate forms a wrinkle dot. The film is coated on the outer surface of the roller, and the optical microstructure is formed by embossing the surface of the light guide plate with a roller.

However, regardless of the process used to fabricate the light guide plate, the wrinkle dots formed on the substrate or the mold by laser processing are affected by the high temperature irradiation of the laser to cause slag splashing and form wrinkles of the recess. The dots, and one or more protrusions are formed around the wrinkled dots, which is commonly known as the crater. Especially when performing the imprint process, since the roller has to apply a certain pressure to the light guide plate, after a long time of pressing, the wrinkle dots are easily broken by the force, for example, the protrusion on the circumference may be bent. Folded or collapsed and fell into the wrinkle dot, resulting in a reduction in the processing life of the substrate or mold. Moreover, the optical microstructure of the surface of the light guide plate embossed by the substrate is affected, resulting in a decrease in the optical microstructure processing yield of the light guide plate.

In addition, the wrinkle dots formed on the mold core or the substrate by laser processing are in the form of depressions, and the shape of the optical microstructure of the light guide plate after being molded by the above-mentioned mold core or substrate is limited. With the application of the light guide plate, the single-state structure can not meet the more diverse light-conducting performance requirements, so how to adjust and improve the shape and processing process of the wrinkle dots on the mold or the substrate used for manufacturing the light guide plate And the service life of the mold or the substrate is one of the topics that need to be improved.

Therefore, the inventor conceived an optical microstructure manufacturing method, a processing machine and a light guide plate mold thereof, and the invention can effectively solve the defects of the microstructures such as the wrinkle dots of the light guide plate mold, so as to have better structural strength. With variability and further increase the imprint yield.

An object of the present invention is to provide an optical microstructure manufacturing method, a processing machine, and a light guide plate mold thereof, which are formed by laser processing on a substrate to form a convex micro-structure, and the substrate can be used as a substrate. The light guide plate mold forms a corresponding concave microstructure on the light guide plate.

In order to achieve the above object, an embodiment of the present invention discloses an optical microstructure manufacturing method comprising the steps of: providing a substrate having a melting point temperature C ₁ ; and irradiating at least one laser beam to the substrate Material, and the laser beam has a processing temperature C ₂ and conforms to C ₁ C ₂ a condition of (1.1 × C ₁ ) such that when the laser beam is bombarded to the substrate, the substrate is in a molten state, and after cooling, at least one convex portion is formed on the surface of the substrate and located at the convex portion a depression on the side of the circumference. By controlling the processing temperature, the substrate is formed into a molten state by being bombarded by the laser beam to facilitate deposition of the molten material to form the convex portion.

Another embodiment of the present invention discloses a laser processing machine for performing the optical microstructure manufacturing method as described above, the laser processing machine comprising: a carrying platform for Placing the substrate; a laser cavity for emitting the laser beam; a processing state monitor for instantly monitoring the change of the protrusion and generating a status signal; and a processing temperature controller for The processing temperature of the laser beam is adjusted according to the status signal. The laser processing machine can instantly monitor the forming state of the convex portion, and adjust the processing temperature through the processing temperature controller at any time to improve the processing yield.

In order to enable the convex portion to be smoothly stacked, in addition to controlling the processing temperature, the energy state of the laser beam can be adjusted. Therefore, the present invention further enables the substrate to be located in the laser beam based on the above embodiments. Outside the focal length, the laser beam is bombarded against the substrate in a defocused manner.

Further, when the substrate is a metal plate, after the plurality of the convex portions are formed, the substrate is coated with a roller to form a plurality of microstructures on the surface of a light guide plate by pressure pressing. Thereby, the substrate of the present invention can be used as a mold for manufacturing a light guide plate, and the light guide plate can form the microstructures corresponding to the convex portions.

In another embodiment, the transverse mode image of the laser beam is rotationally symmetric, such that the molten region formed by the laser beam bombarding the substrate is more conducive to the accumulation of the convex portion.

In yet another embodiment, the present invention discloses a light guide plate mold which is processed by the optical microstructure manufacturing method described above. The light guide plate mold comprises: a substrate having a transfer surface for transliteration a light guide plate; and a plurality of optical microstructures on the transfer surface, any of the optical microstructures being composed of a convex portion and a concave portion on a circumferential side of the convex portion; wherein the convex portion is It consists of the substance originally located in the depression.

Based on the above embodiments, the present invention discloses one application of the light guide plate mold. Even if the substrate is a metal plate, and a roller is coated to transfer the light guide plate by compression.

In summary, the optical microstructure manufacturing method of the present invention is to form the convex portion by laser processing by controlling the parameters of the laser beam, and the requirement of the convex portion in the present invention. The parameter adjustment of the laser beam can also make the formed convex portion have better structural rigidity. In addition, after the plurality of the convex portions are formed, the substrate can be used as a mold of the light guide plate, and can be coated with the roller on the roller to perform imprint processing on the light guide plate. The light guide plate forms a plurality of microstructures corresponding to the convex portions to facilitate the dimming and light guiding performance of the light guide plate in subsequent applications.

10‧‧‧Substrate

101‧‧‧ convex

102‧‧‧Depression

11‧‧‧Laser beam

2‧‧‧Light guide plate

20‧‧‧Microstructure

3‧‧‧Rollers

4‧‧‧Laser processing machine

40‧‧‧Loading platform

41‧‧‧Laser Resonator

42‧‧‧Processing condition monitor

43‧‧‧Processing temperature controller

5‧‧‧Light guide plate mould

50‧‧‧Substrate

501‧‧‧Transfer surface

51‧‧‧Optical microstructure

511‧‧‧ convex

512‧‧‧Depression

S101~S102‧‧‧Steps

A‧‧‧defocused state

B‧‧‧ Focus state

C‧‧‧ defocused state

Fig. 1 is a flow chart showing the steps of the first embodiment of the present invention.

Fig. 2 is a perspective view showing the substrate of the first embodiment of the present invention after processing.

Fig. 3 is a schematic view (1) of the processing of the first embodiment of the present invention.

Fig. 4 is a schematic view (2) of the processing of the first embodiment of the present invention.

Fig. 5 is a schematic view showing the application of the substrate after processing according to the first embodiment of the present invention.

Figure 6 is a schematic view showing the processing of the second embodiment of the present invention.

Figure 7 is a perspective view of a third embodiment of the present invention.

In order for your review board to have a clear understanding of the contents of the present invention, please refer to the following description for matching drawings.

Please refer to Figures 1, 2 and 3 to 4, which are steps of the first embodiment of the present invention. The schematic diagram of the process, the schematic diagram of the substrate after processing and the schematic diagram of each processing. The present invention discloses an optical microstructure manufacturing method comprising the following steps.

First, a substrate 10 is provided, which is step S101. Wherein, the substrate 10 has a melting point temperature C ₁ . Next, as shown in step S102, at least one laser beam 11 is irradiated to the substrate 10 to bombard the laser beam 11 to the substrate 10, so that the substrate 10 is in a molten state, and then after cooling The surface of the substrate 10 is formed with at least one convex portion 101 and one concave portion 102 on the circumferential side of the convex portion 101. Wherein, the laser beam 11 has a processing temperature C ₂ and conforms to C ₁ C ₂ The condition of (1.1× C ₁ ), by the constraint condition to ensure that the laser beam 11 bombards the substrate 10, the substrate 10 can be maintained in a molten state, avoiding the processing temperature C _{2 being} too high, thereby causing the The substrate 10 is turned into a vaporized state, and after the bombardment of the laser beam 11, the depressed portion 102 or even the perforations are formed only on the surface of the substrate 10. For example, in the case of a general steel sheet as the substrate 10, the melting point temperature C ₁ is 1200 ° C, and the processing temperature C ₂ can be allowed to be in a temperature range between 1200 ° C and 1320 ° C to avoid the processing temperature C. _{2 is} too low to melt the substrate 10 smoothly, or the processing temperature C _{2 is} too high to cause the substrate 10 to be vaporized. The processing temperature C ₂ of the laser beam 11 can be controlled by the frequency and/or power of the laser beam 11 . In general, after the laser beam 11 is irradiated onto the substrate 10 and is in a molten state, the molten substrate 10 is gradually cooled and gradually formed, thereby forming the convex portion 101, and the region melted on the circumferential side of the convex portion 101 is formed. The concave portion 102 is formed with respect to the convex portion 101.

In one embodiment, the substrate 10 can be positioned outside the focal length of the laser beam 11 to cause the laser beam 11 to be bombarded against the substrate 10 in a defocusing manner, thereby enabling the laser to be used. The energy distribution of the light beam 11 is in an optimum state, and the energy of the laser beam 11 is prevented from being excessively concentrated or dispersed, so that the substrate 10 cannot be cooled by the molten state and the temperature is formed to form the convex portion. 101. The laser beam is modulated by the electromagnetic wave through the gain medium to adjust the characteristics of the output laser beam. The gain medium can be enclosed in the optical resonant cavity to further generate electromagnetic waves in the optical resonant cavity, and the electromagnetic wave continuously flows back and forth. After the gain medium, the laser beam is output when the critical state is reached. When the laser beam 11 is output, the energy accumulation state can be further adjusted, that is, generally referred to as out-of-focus, focus and defocus state, and the resonance cavity from the output of the laser beam 11 is respectively from near to far. The defocus state a of the laser beam, the focus state b, and the defocus state c. When the laser beam 11 is out of focus state a, its energy is dispersed and gradually gathers, so that after the laser beam 11 continues to travel, it is turned into a focus state b, and the laser beam 11 in this state is irradiated to the laser beam 11 When the substrate 10 is used, the substrate 10 is easy to form a wide and shallow depth groove; when the laser beam 11 continues to advance to the in-focus state b, its energy is concentrated at a little closer, and the laser beam in this state When the substrate 10 is irradiated onto the substrate 10, the substrate 10 is easily vaporized to form a deep groove or even a perforated state; the laser beam 11 is converted from the in-focus state b to the defocused state c. When the energy is concentrated, it is gradually dispersed, that is, the energy is diffused and distributed, and the energy of the laser beam 11 is gradually increased from the center. The laser beam 11 in this state is irradiated to the state. After the substrate 10, the area of the molten region formed in the substrate 10 is larger than that of the laser beam 11 in the non-defocused state c, and the temperature of the substrate 10 corresponding to the edge adjacent to the laser beam 11 is relatively high. The central region has a lower temperature relative to the edge region, and the substrate 10 in a molten state is available The bulk of the cooling is formed at the lower portion of the projection 101, the laser beam 11 adjacent the edge region of the recessed portion 102 is formed. Therefore, as shown in FIG. 3, in the present embodiment, the laser beam 11 is bombarded with the substrate 10 in an out-of-focus state to form the substrate 10 in a molten state by being irradiated by the laser beam 11, wherein The laser beam 11 of Fig. 3 is shown in an enlarged state to facilitate the description of the various states of the laser beam 11. Then, as shown in FIG. 4, the molten substrate 10 is gradually deposited to form the convex portion 101. And the recessed portion 102.

Moreover, when electromagnetic waves are transmitted in the optical resonant cavity, they are affected by the boundary of the optical resonant cavity and affect the electromagnetic field state, which is generally referred to as the mode of the laser beam, and can be further divided into a longitudinal mode and a transverse mode. (Transverse Mode), different modes of laser beam, in addition to the difference in light intensity, also have a difference in frequency. The horizontal mode light intensity distribution can be observed by the naked eye to see the image of the laser beam, and the longitudinal mode can not be seen by the naked eye. Common transverse mode images come in two forms, one is Hermite-Gaussian Modes and the other is Laguerre-Gaussian Modes. Since the transverse mode image of the laser beam 11 can be effectively adjusted by the boundary condition, and the structural strength and the morphology of the convex portion 101 are considered, the present invention is used to make the transverse mode of the laser beam 11 in one embodiment. The image is in a rotationally symmetrical state, for example, a circular transverse mode image, whereby after the laser beam 11 bombards the substrate 10, the substrate 10 is formed into a ring-shaped molten region, that is, In the substrate 10, the temperature of the portion irradiated by the laser beam 11 in an annular portion is higher than a central region surrounded by the state, and the substrate 10 in the molten state can be cooled due to the low temperature in the central region, so that the substrate 10 can be cooled. The convex portion 101 is formed to be stacked toward the center, and the concave portion 102 is annular on the circumferential side of the convex portion 101. However, the corresponding rotationally symmetric transverse mode image can be selected according to the aspect in which the convex portion 101 is required to be formed, and the present invention is not limited thereto.

Please refer to FIG. 5, which is a schematic diagram of the application of the substrate after processing according to the first embodiment of the present invention. In addition, the substrate 10 can be a metal plate or a metal mold to facilitate the formation of the plurality of microstructures 20 on the light guide plate 2 through various processing methods after the plurality of the convex portions 101 are formed. When the substrate 10 is a metal mold, the light guide plate 2 can be formed by injection molding or pouring, and the convex portion 101 corresponding to the light guide plate 2 has the microstructures 20. And when the substrate 10 is In the case of a metal plate, after the convex portions 101 are formed, the substrate 10 can be coated with a roller 3 to form a plurality of microstructures 20 on the surface of the light guide plate 2 by compression. After the base material 10 is processed by the laser beam 11 to form the convex portions 101, the light guide plate 2 can be embossed through the roller 3 to match at least one surface of the light guide plate 2, etc. The protrusions 101 form the microstructures 20 in a recessed manner, so that the light guide plate 2 can adjust the state of light by the microstructures 20 when applied. In addition, since each of the convex portions 101 is formed by cooling and stacking the molten substrate 10, and has a certain contact area with the light guide plate 2 at the time of imprinting, even if it is coated on the roller 3 and pressed, it is directed against The light guide plate 2 is processed to form the microstructures 20. The convex portions 101 are also less likely to be cracked by force, and have better structural strength, in addition to ensuring the shape and size of the microstructures 20 and the like. In addition to increasing the production yield of the light guide plate 2, the service life of the substrate 10 can also be extended.

Please refer to Fig. 6, which is a schematic view of the processing of the second embodiment of the present invention. In the present embodiment, the present invention discloses a laser processing machine 4 for performing the optical microstructure manufacturing method as described above, and the technical features of the first embodiment are not described herein. The laser processing machine 4 includes a carrying platform 40, a laser resonant cavity 41, a processing state monitor 42 and a processing temperature controller 43.

The carrying platform 40 is configured to place the substrate 10, and the laser cavity 41 is configured to emit the laser beam 11 to process the substrate 10 to form at least one of the protrusions 101 and the recesses 102. The processing state monitor 42 is configured to monitor the change of the convex portion 101 in real time, and generate a state signal according to the changed state of the convex portion 101. The processing state monitor 42 can be connected to the side of the carrying platform 40 or It can be erected independently, and only the processing state monitor 42 can smoothly and accurately monitor the convex portion 101. The processing temperature controller 43 is in telecommunication connection with the processing state monitor 42 to control the processing temperature C _{2 by} adjusting the power or frequency of the laser beam 11 according to the state signal. The processing temperature controller 43 and the processing state monitor 42 can be connected by wireless or wired mode. In the embodiment, the processing temperature controller 43 is integrated with the laser cavity 41 and is transparent. The wireless mode is electrically connected to the processing state monitor 42 as an example. The change state of the convex portion 101 is such that after the laser beam 11 bombards the substrate 10, the substrate 10 cannot be smoothly formed into a molten state, thereby causing the substrate 10 to be formed in a sufficiently molten state. In the convex portion 101, the processing state monitor 42 generates and transmits the status signal to the processing temperature controller 43 so that the processing temperature C ₂ can be increased according to the status signal. Alternatively, the substrate 10 is in a molten state after being irradiated by the laser beam 11, but the convex portion 101 cannot be formed by cooling or even forms a vaporized state. In this case, the processing temperature C ₂ may be Therefore, the processing status monitor 42 generates and transmits the status signal to the processing temperature controller 43 according to the condition to lower the processing temperature C ₂ . Thereby, the laser processing machine 4 of the present invention can monitor the processing state at any time, and adjust the processing temperature C ₂ in time to improve the processing yield and ensure that the convex portion 101 can be formed according to the desired state. .

In the same manner as described above, in order to maintain the forming yield of the convex portion 101, the substrate 10 can be positioned outside the focal length of the laser beam 11 by adjusting the distance between the carrying platform 40 and the laser resonant cavity 41. The laser beam 11 is subjected to bombardment in a defocusing manner for the substrate 10, and the transverse mode image of the laser beam 11 can be rotationally symmetric. In addition, the substrate 10 can be a metal plate or a metal mold to facilitate subsequent fabrication of a light guide plate and a plurality of microstructures thereon by various processing methods. When the substrate 10 is a metal plate, the plurality of the convex portions 101 are formed and coated with a roller 3 to form the microstructures 20 on the surface of the light guide plate 2 by compression. can As shown in Figure 5. The detailed technical features have been described in the previous embodiment, and thus will not be further described herein.

Please refer to FIG. 7, which is a perspective view of a third embodiment of the present invention. In the present embodiment, the present invention discloses a light guide plate mold 5 which is processed by the optical microstructure manufacturing method according to the first embodiment. The light guide plate mold 5 includes a substrate 50 and a plurality of opticals. Microstructure 51.

The substrate 50 has a transfer surface 501 for transducing a light guide plate. The optical microstructures 51 are located on the transfer surface 501, and any of the optical microstructures 51 is composed of a convex portion 511 and a concave portion 512 located on the circumferential side of the convex portion 511, wherein the convex portion 511 is composed of The material originally located in the recessed portion 512 is formed by the optical microstructure manufacturing method as described in the first embodiment, and after the laser beam is bombarded against the substrate 50, the substrate 50 is placed at the bombardment position. The convex portion 511 and the depressed portion 512 are formed by being melted and cooled, so that the convex portion 511 is deposited on the substrate 50 originally located in the molten region. Referring to FIG. 5, as described above, after the laser beam is irradiated, the substrate 50 is formed with the convex portion 511 and the concave portion 512 on the circumferential side thereof to form the optical microstructure 51. The optical microstructure 51 can be transferred to a light guide plate, for example, by the process of coating the roller and forming a corresponding microstructure on the light guide plate by imprinting.

The optical microstructure manufacturing method, the processing machine and the light guide plate mold thereof of the present invention control the processing temperature of the laser beam to irradiate the substrate to form a molten state, and Cooling and stacking the convex portion and the concave portion on the circumferential side thereof to transfer the light guide plate by using the substrate having the convex portion and the concave portion as a light guide plate, so that the surface of the light guide plate can be The convex portion is formed to form a microstructure. In order for the convex part to be stacked smoothly Forming, the present invention also defines the processing temperature and the energy state of the laser beam so that the formed convex portion has a more precise shape and size. Moreover, the convex portion prepared by the invention has excellent structural strength to avoid the phenomenon of cracking and destruction caused by long-time processing, and causes a large error in the shape and size of the microstructure formed by the light guide plate.

However, the above description is only for the preferred embodiment of the present invention and is not intended to limit the scope of the present invention; therefore, equivalent changes and modifications may be made without departing from the spirit and scope of the invention. Within the scope of the patent of the present invention.

S101~S102‧‧‧Steps

Claims (10)

An optical microstructure manufacturing method comprising the steps of: providing a substrate having a melting point temperature C ₁ ; and irradiating at least one laser beam to the substrate, and the laser beam has a processing temperature C ₂ And in accordance with C ₁ C ₂ a condition of (1.1 × C ₁ ) such that when the laser beam is bombarded to the substrate, the substrate is in a molten state, and after cooling, at least one convex portion is formed on the surface of the substrate and located at the convex portion a depression on the side of the circumference. The optical microstructure manufacturing method of claim 1, wherein the substrate is located outside a focal length of the laser beam, and the laser beam is bombarded against the substrate by a defocusing method. The optical microstructure manufacturing method according to claim 2, wherein the substrate is a metal plate, and after the plurality of the convex portions are formed, the substrate is coated with a roller to pass through the pressure. The method forms a plurality of microstructures on a surface of a light guide plate. The optical microstructure manufacturing method of claim 2, wherein the transverse mode image of the laser beam is rotationally symmetric. A laser processing machine for performing the optical microstructure manufacturing method according to claim 1, wherein the laser processing machine comprises: a carrying platform for placing the substrate; and a laser cavity And a processing state monitor for instantly monitoring the change of the convex portion and generating a state signal; and a processing temperature controller for adjusting the laser beam according to the state signal The plus Working temperature. The processing machine of claim 5, wherein the substrate is located outside a focal length of the laser beam, and the laser beam is bombarded against the substrate by a defocusing method. The processing machine of claim 6, wherein the substrate is a metal plate, and after the plurality of the convex portions are formed, the substrate is coated with a roller to pass through the compression method. A plurality of microstructures are formed on the surface of a light guide plate. The laser processing machine of claim 6 or 7, wherein the transverse mode image of the laser beam is rotationally symmetric. A light guide plate mold is processed by the optical microstructure manufacturing method according to claim 1, wherein the light guide plate mold comprises: a substrate having a transfer surface for transferring a light guide plate; And a plurality of optical microstructures on the transfer surface, any of the optical microstructures being composed of a convex portion and a concave portion on a circumferential side of the convex portion; wherein the convex portion is originally located The substance of the depression is composed of. The light guide plate mold according to claim 9, wherein the substrate is a metal plate for covering a roller, and the light guide plate is transferred by compression.