CN100395605C

CN100395605C - Light transmitting board for display

Info

Publication number: CN100395605C
Application number: CNB021520194A
Authority: CN
Inventors: 林明辉; 李青谚
Original assignee: Hongfujin Precision Industry Shenzhen Co Ltd; Hon Hai Precision Industry Co Ltd
Current assignee: Hongfujin Precision Industry Shenzhen Co Ltd; Hon Hai Precision Industry Co Ltd
Priority date: 2002-11-18
Filing date: 2002-11-18
Publication date: 2008-06-18
Anticipated expiration: 2022-11-18
Also published as: CN1501139A

Abstract

The present invention relates to a light guiding board for a display, which comprises a base body which further comprises an incident surface for receiving light, an emergent surface for leading out the light in the light guiding board and at least one side surface connected with the emergent surface, wherein the incident surface and the emergent surface are plated with antireflective films, and at least one side surface is plated with a reflecting film; the light guiding board solves the problem of the lower light utilization ratio of a light guiding board in the prior art.

Description

The light guide plate that is used for display

[technical field]

The present invention relates to a kind of light guide plate, refer to a kind of light guide plate that is used for display especially.

[background technology]

Light guide plate is an important optical module of LCD light-source system, and it and other optical module such as light source, reflecting plate, diffuser plate and prism plate constitute back light system, for the liquid crystal display displays pattern provides required light.Light guide plate mainly comprises light entrance face, exit facet, bottom surface and a plurality of side, and its effect is that the light that guiding point light source or line source send penetrates from exit facet, improves the homogeneity of panel glorious degrees and luminosity thereof simultaneously.

A kind of prior art light guide plate can be consulted the United States Patent (USP) the 5th of bulletin on September 7th, 1999,947, No. 578 (with reference to Fig. 1), this light guide plate 1 comprises an optical waveguide matrix 10, this matrix 10 further comprises first surface 11, second surface 12 and side 15,16,19, matrix 10 1 ends are provided with two grooves 13 and are used to insert luminescent device (figure does not show), each groove 13 has sidewall 14, the luminescent device issued light can be injected in the matrix 10 from this sidewall 14, one specular reflective material 17 is coated on the second surface 12 of this matrix 10, one scattering material 18 is coated in the first surface 11 of this matrix 10, this specular reflective material 17 is used for and will arrives the light reflection of second surface 12, it is penetrated from first surface 11, and this scattering material 18 is used to spread the light that penetrates from matrix 10.But, this light guide plate 1 only applies specular reflective material 17 at second surface 12, make enter light guide plate 1 light some penetrate from the side 15,16,19 of light guide plate; And light has part light reflection to take place and can not enter matrix 10 at sidewall 14 when entering light guide plate 1, by first surface 11 time, also has part light to reflect at first surface 11, returns matrix 10.Therefore, the light that sends from luminescent device has major part to be depleted and the usefulness that can't penetrate for demonstration from first surface 11, so the loss of the prior art light guide plate is bigger, light utilization efficiency is lower.

Certainly, industry is also sticked sealing strip and is penetrated to prevent light through the light guide plate side of being everlasting, but the sealing bar combines with light guide plate in the adhesion mode, easy impaired coming off in carrying or other operation; And the sealing bar is difficult to cover the light guide plate side fully, also has never sealed side that is covered of part light to penetrate, and light utilization efficiency is still lower.

Therefore, need provide a kind of light utilization efficiency higher light guide plate.

[summary of the invention]

The technical problem to be solved in the present invention is to provide a kind of light guide plate that is used for display of high light utilization efficiency.

The technical problem to be solved in the present invention is achieved in that provides a kind of light guide plate that is used for display, this light guide plate comprises a matrix, this matrix further comprises the plane of incidence in order to reception light, an exit facet and an at least one side that links to each other with exit facet in order to the light outgoing in the guiding light guide plate, wherein, the plane of incidence and exit facet are coated with anti-reflective film, and at least one side is coated with reflectance coating.

Compare with the existing light guide plate that is used for display, the invention has the beneficial effects as follows: because this light guide plate is coated with anti-reflective film at the plane of incidence and exit facet, be coated with reflectance coating at least one side, do not reflect when making light through the plane of incidence and exit facet, also can not penetrate and leak, thereby effectively improve the utilization factor of light from the light guide plate side.

[description of drawings]

Fig. 1 is the stereographic map of prior art light guide plate.

Fig. 2 is the stereographic map that the present invention is used for light guide plate first embodiment of display.

Fig. 3 is the stereographic map that the present invention is used for light guide plate second embodiment of display.

Fig. 4 is the stereographic map that the present invention is used for light guide plate second another angle of embodiment of display.

Fig. 5 adopts the present invention to be used for the three-dimensional exploded view of light-source system of the light guide plate of display.

[embodiment]

Please refer to Fig. 2, the light guide plate 2 that the present invention is used for display comprises matrix 20 and setting reflectance coating 27 and anti-reflective film 28 thereon.Wherein, matrix 20 further comprise the plane of incidence 21, the exit facet 22 adjacent with the plane of incidence 21, with exit facet 22 opposed bottom surface 23 and

other side

24,25,26.Wherein, the plane of incidence 21 is provided with anti-reflective film 28 with exit facet 22, bottom surface 23 is provided with reflectance coating 27 with

other side

24,25,26, this light guide plate 2 generally can be used for the back light system in the liquid crystal display device, light source (figure does not show) preferably adopts line source, as electroluminescent lamp, cold cathode fluorescent lamp etc.The light source issued light enters in the light guide plate 2 from the plane of incidence 21 of light guide plate 2, part light directly penetrates light guide plate 2 from exit facet 22, part light also penetrates light guide plate 2 from exit facet 22 after the reflection of bottom surface 23, other small part light after 24,25,26 reflections of side finally from exit facet 22 outgoing.Therefore, in the bottom surface 23,

side

24,25,26 is provided with reflectance coating 27, can make most light arrive bottom surface 23 and side reflection can take place in 24,25,26 o'clock and can not penetrate from this face, at the plane of incidence 21, exit facet 22 anti-reflective film 38 is set, most light will be transmitted when the plane of incidence 21 and exit facet 22 and can not reflects.In addition, also can be 23 a plurality of grooves or a plurality of projection (figure does not show) be set, thereby can reduce the chance of light, can make that again light guide plate 2 emergent lights are more even from light guide plate 2 bottom surfaces, 23 outgoing in the bottom surface.

The second embodiment of the present invention please refer to Fig. 3 and Fig. 4, and the difference of itself and first embodiment only is that the light guide plate that is used for display 3 of this embodiment adopts the plane of incidence 31 that matches with a plurality of pointolites (as light emitting diode, figure does not show).This light guide plate 3 that is used for display comprises matrix 30 and setting reflectance coating 37 and anti-reflective film 38 thereon.Wherein, matrix 30 further comprise the plane of incidence 31, the exit facet 32 adjacent with the plane of incidence 31, with exit facet 32 opposed bottom surface 33 and

other side

34,35,36.The plane of incidence 31 1 sides of its matrix 30 form a plurality of grooves 313, to accommodate a plurality of pointolites, so, the plane of incidence 31 comprise a plurality of planes 311 and respectively with a plurality of planes 311 staggered adjacent concave surfaces 312, at concave surface 312, the exit facet 32 coating anti reflection films 38 of these light guide plate matrix 30 planes of incidence 31, in the bottom surface 33, plane 311 and

other side

34,35,36 plating reflectance coatings 37.In addition, also can be 33 a plurality of grooves or a plurality of projection (figure does not show) be set in the bottom surface.

In addition, the plane of incidence that the present invention is used for the light guide plate of display also can be oppositely arranged with exit facet, and at the plane of incidence and exit facet coating anti reflection film, in other face plating reflectance coating.The light guide plate that the present invention is used for display also can be provided with two planes of incidence, and this two plane of incidence is the coating anti reflection film all.

The matrix that the present invention is used for the light guide plate of display can adopt acrylic resin, also can use transparent resin material such as polycarbonate resinoid and glass etc., and its refractive index is preferably between 1.488 to 1.492.Reflectance coating, anti-reflective film can adopt the plated film mode with Ta ₂O ₅With SiO ₂Be deposited on the matrix and form, its plated film mode can be physical vaporous deposition, as hot vapour deposition method, electricity slurry sputtering method and ion beam sputtering method; Also can adopt chemical vapour deposition technique and other film growth method, in visible-range (500nm to 700nm), this reflectance coating can make the specific wavelength reflection more than 98%, and anti-reflective film then can make light transmission rate be promoted to more than 94% by 89%.And a plurality of grooves or protruding dot matrix are set in bottom surface of light guide plate, and both can adopt non-printing-type processing procedure, as chemical etching texture method, laser direct-writing method, precision optical machinery delineation method and light lithography method, also can adopt the dot matrix printing process to handle.

Fig. 5 adopts the present invention to be used for the three-dimensional exploded view of light-source system of the light guide plate of display, this light-source system 4 comprises light guide plate 2, be positioned at the light source 41 of light guide plate 2 planes of incidence 21 1 sides, place the diffuser plate 43 and the prism plate 44 of light guide plate 2 exit facets 22 1 sides, wherein, diffuser plate 43 is between light guide plate 2 and prism plate 44.Diffuser plate 43 is to stamp tiny glass beads in substrate two bottom surfaces 431,432 and make, and is used for and will be incident to the light scattering of diffuser plate 43.Prism plate 44 is to form the bar shaped microprisms that a series of circular rules change and make on substrate, thus the brightness that its optical convergence that is used for dispersing improves light.When light source 41 issued lights when the plane of incidence 21 enters light guide plate 2, penetrate from exit facet 22, after diffuser plate 43 diffusions, assemble through prism plate 44 again, arrive liquid crystal display (figure does not show) at last.

Claims

1. light guide plate that is used for LCD, this light guide plate comprises a matrix and is arranged on reflectance coating on this matrix, this matrix further comprises a plane of incidence that receives light, guide lights exit facet and at least one side that links to each other with exit facet from the light guide plate outgoing, it is characterized in that: the plane of incidence and exit facet are coated with anti-reflective film, and at least one side is coated with reflectance coating.

2. the light guide plate that is used for LCD according to claim 1 is characterized in that: this plane of incidence and this exit facet are oppositely arranged.

3. the light guide plate that is used for LCD according to claim 1 is characterized in that: this plane of incidence is adjacent with this exit facet, and this light guide plate further comprises a bottom surface relative with this exit facet.

4. the light guide plate that is used for LCD according to claim 3 is characterized in that: this bottom surface of light guide plate further is provided with a plurality of grooves.

5. the light guide plate that is used for LCD according to claim 3 is characterized in that: this bottom surface of light guide plate further is provided with a plurality of projectioies.

6. the light guide plate that is used for LCD according to claim 1 is characterized in that: this reflectance coating and anti-reflective film are by Ta ₂O ₅With SiO ₂Intersecting forms.

7. light guide plate that is used for LCD, this light guide plate comprises a matrix and is arranged on reflectance coating on this matrix, this matrix further comprises a plane of incidence that receives light, guide lights exit facet and at least one side that links to each other with exit facet from the light guide plate outgoing, it is characterized in that: this plane of incidence further comprise a plurality of planes and respectively with the staggered adjacent and concave surface that caves inward in a plurality of planes, the concave surface and the exit facet of the plane of incidence are coated with anti-reflective film, and the plane of the plane of incidence or at least one side are coated with reflectance coating.