CN105403949A - Thin-type light guiding plate and preparation method thereof - Google Patents

Abstract

The invention provides a thinner light guide plate, which includes a base plate, a transparent adhesive layer is laid on the top surface of the base plate, total reflection microstructure dots are hot-printed on the bottom surface of the base plate, and convex points are formed on the incident end of the transparent adhesive layer. The height of the top surface of the boss is adapted to the upper optical path of the incident light source. The present invention also provides a method for preparing a thinner light guide plate, using acrylic sheet extrusion, cutting, UV glue embossing, drying, cutting into small plates, dot embossing, and final molding, wherein the UV glue embossing is The UV glue is coated on the embossing mold, and then the embossing mold is embossed with the board, and the UV glue is transferred to the board. In the present invention, the incident end of the transparent adhesive layer on the top surface of the light guide plate is designed as a boss, and the height of the top surface of the boss is adapted to the upper optical path of the incident light source. While achieving thinness, it matches the thickness of the LED lamp to achieve brightness. requirements.

Description

A kind of thin light guide plate and its preparation method

technical field

The invention relates to the technical field of liquid crystal display backlight sources, in particular to a thinned light guide plate and a preparation method thereof.

Background technique

For the side-type backlight module, it includes light source, light guide plate, various optical films and other components. The light guide plate is the most critical part. Its main function is to guide the scattering direction of light, convert the point light source incident from the side into a uniform surface light source emitted from the front, and improve the brightness and uniformity of the backlight module. With the development trend of thinner flat panel display devices, small size (3~10") backlights are becoming thinner and thinner, and the key components of the light guide plate and LED lights are also thinner. The thickness of the light guide plate is also required to reach 0.2 ~0.6mm, while the commonly used thickness of LED lamps is 0.4mm and above, which is not enough to meet the development requirements of thinning.

Contents of the invention

The invention provides a thinner light guide plate, which is applied to a small-size backlight module to realize thinner backlight.

In order to solve the problems of the technologies described above, the present invention adopts the following technical solutions:

A thin light guide plate, comprising a substrate, the top surface of the substrate is laid with a transparent adhesive layer, the bottom surface of the substrate is thermally embossed with microstructure dots for breaking the total reflection of the optical path, and the incident end of the transparent adhesive layer is formed with The boss, the height of the top surface of the boss is adapted to the upper light path of the incident light source.

Preferably, the microstructure dots are ring-shaped structures imprinted along the bottom surface of the substrate.

Preferably, the boss is a right-angled trapezoid, and the right-angled waist of the right-angled trapezoid is perpendicular to the light path of the incident light source.

Preferably, the substrate is made of acrylic or polycarbonate.

The present invention also provides a method for preparing a thinned light guide plate, comprising the following steps:

1) Raw materials are produced into plates through extrusion equipment;

2) The plate is polished by the polishing roller and then cut to become a large plate that meets the specification requirements;

3) Emboss the transparent adhesive layer with a right-angled trapezoidal boss onto the coating surface of the large plate through the embossing mold;

4) Light-cure the adhesive layer on the large board, and then perform precision die-cutting to become a small board that meets the size specifications;

5) Transfer printing of microstructure dots on the non-coated surface of the small plate by hot embossing equipment;

6) Use a laminating machine to cover both sides of the small plate with a protective film, and the thin light guide plate is completed.

Further, in step 3), the transparent adhesive layer is formed by applying UV glue to an embossing mold with an inverted right-angled trapezoidal notch at one end through coating equipment.

Preferably, in step 5), the thermal embossing device includes an upper photoconductive wheel and a lower embossing wheel, and the embossing wheel is provided with a plurality of protrusions for transferring microstructure dots.

Further, a destaticizing step is included between step 5) and step 6), and an ion fan is used to destaticize the coated surface of the small plate.

It can be seen from the above technical solutions that the invention designs the incident end of the transparent adhesive layer on the top surface of the light guide plate as a boss, and the height of the top surface of the boss is adapted to the upper optical path of the incident light source. The thickness of the lamp is matched to meet the brightness requirement.

Description of drawings

Fig. 1 is a structural schematic diagram of a thinned light guide plate of the present invention, and shows the position of the LED light source;

Fig. 2 is the production line flowchart of preparation method of the present invention;

Fig. 3 is the schematic diagram of the preparation step of transparent adhesive layer among the present invention;

Fig. 4 is a schematic diagram of the microstructure imprinting step in the present invention.

In the figure: 10. Substrate, 20. Transparent adhesive layer, 21. Boss, 30. Microstructure dots, 40. LED light source, 51. Coating equipment, 52. Embossing mold, 61. Light guide wheel, 62. Embossing wheel.

detailed description

A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in Figure 1, the thinned light guide plate includes a substrate 10. In this embodiment, an acrylic plate is used with a thickness of 0.2-0.6 mm. A transparent adhesive layer 20, preferably a UV adhesive layer, is laid on the top surface of the substrate. The thickness is 0.003~0.02mm, and the hardness is as high as 2H, which has a good wear-resistant and scratch-resistant function. The bottom surface of the substrate 10 is thermally embossed with microstructure dots 30. The microstructure dots are preferably a ring-shaped structure embossed along the bottom surface of the substrate, which is used to break the total reflection of the optical path and play the role of scattering dots. effect.

Small size (3~10") backlight is thin design, the thickness of the light guide plate should reach 0.2~0.6mm, it needs to match the LED light source 40 (thickness is 0.4mm and above), and can be formed on the incident end of the transparent adhesive layer 20. Boss 21, the top surface height of this boss is adapted to the upper end light path of LED light source 40.Described boss 21 is designed as a right-angled trapezoid, and the right-angled waist of this right-angled trapezoid is perpendicular to the light path of LED light source 40, so design can The incident light source is completely guided into the light guide plate, and can meet the thinning requirements. It is applied to the small-size backlight module to realize the thinning of the backlight.

The present invention also provides a method for preparing a thin new type of light guide plate, using acrylic sheet (PMMA) to extrude, cut, UV glue embossing, drying, cutting into small plates, dot embossing, and finally forming, wherein UV Glue imprinting is that UV glue is coated on the embossing mold, and then the imprinting mold is embossed with the plate, and the UV glue is transferred to the plate.

In conjunction with accompanying drawing 2, the preparation method of the present invention is specifically described as follows:

001: PMMA particles are produced into acrylic sheets through extrusion equipment;

002: The plate is polished by the polishing roller and then cut to become a large plate that meets the specification requirements;

003: Emboss a transparent adhesive layer with a right-angled trapezoidal boss onto the coating surface of the slab through the embossing mold. The transparent adhesive layer is applied to the embossing mold 52 with an inverted right-angled trapezoidal notch at one end through the coating equipment 51. Formed by UV glue coating, referring to Figure 3, the imprint mold 52 needs to be turned over before embossing;

004: Light-cure the adhesive layer on the large board, generally irradiated by UV light, dry and cure to make the hardness above 2H, with anti-scratch function, and then carry out precision die-cutting to become a small board that meets the size and specification requirements ;

005: Transfer the microstructure dots on the non-coated surface of the small board through the thermal embossing equipment, wherein the thermal embossing equipment includes the upper light guide wheel 61 and the lower embossing wheel 62, and the embossing wheel is equipped with multiple A bump for transferring the microstructure dots, referring to Figure 4;

006: Use an ion fan to destaticize the coated surface of the small plate;

007: Then use a laminating machine to cover both sides of the small plate with a protective film;

008: The finished thin light guide plate is finished.

The above-mentioned embodiments are only descriptions of the preferred embodiments of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, those skilled in the art may make various modifications to the technical solutions of the present invention. and improvements, all should fall within the scope of protection determined by the claims of the present invention.

Claims (8)

1. A thin light guide plate, characterized in that it comprises a substrate, the top surface of the substrate is laid with a transparent adhesive layer, and the bottom surface of the substrate is hot-printed with microstructure dots for breaking the total reflection of the optical path, and the transparent adhesive A boss is formed at the incident end of the layer, and the height of the top surface of the boss is adapted to the upper optical path of the incident light source. 2 . The thinned light guide plate according to claim 1 , wherein the microstructure dots are ring-shaped structures embossed along the bottom surface of the substrate. 3 . 3 . The thinned light guide plate according to claim 1 , wherein the boss is a right-angled trapezoid, and the right-angled waist of the right-angled trapezoid is perpendicular to the light path of the incident light source. 4 . 4. The thinned light guide plate according to claim 1, wherein the substrate is made of acrylic or polycarbonate. 5. A method for preparing a thin light guide plate, comprising the steps of: 1) Raw materials are produced into plates through extrusion equipment; 2) The plate is polished by the polishing roller and then cut to become a large plate that meets the specification requirements; 3) Emboss the transparent adhesive layer with a right-angled trapezoidal boss onto the coating surface of the large plate through the embossing mold; 4) Light-cure the adhesive layer on the large board, and then perform precision die-cutting to become a small board that meets the size specifications; 5) Transfer printing of microstructure dots on the non-coated surface of the small plate by hot embossing equipment; 6) Use a laminating machine to cover both sides of the small plate with a protective film, and the thin light guide plate is completed. 6. The preparation method according to claim 5, characterized in that, in step 3), the transparent adhesive layer is formed by applying UV glue to an imprinting mold with an inverted right-angled trapezoidal notch at one end by coating equipment . 7. The preparation method according to claim 5, characterized in that, in step 5), the thermal embossing equipment includes a light guide wheel at the upper end and an embossing wheel at the lower end, and the embossing wheel is provided with a plurality of Transfers raised microstructured dots. 8 . The preparation method according to claim 5 , wherein a destaticizing step is further included between step 5) and step 6), and an ion fan is used to destaticize the coated surface of the small plate.