CN100376977C

CN100376977C - Area Light source

Info

Publication number: CN100376977C
Application number: CNB021497133A
Authority: CN
Inventors: 吕昌岳; 陈杰良
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: 2002-12-20
Filing date: 2002-12-20
Publication date: 2008-03-26
Anticipated expiration: 2022-12-20
Also published as: CN1508603A

Abstract

The present invention relates to a surface source applied to liquid crystal displays, which comprises a plurality of point light sources, a light conducting plate and a plurality of scattering points, wherein the light conducting plate comprises a light incidence face and a light emergence face crossed with the light incidence face; the point light sources are positioned at one side of the light incidence face of the light conducting plate; the scattering points are integrally formed on the light incidence face of the light conducting plate in an inward recessed mode; at least every three scattering points corresponds to one point source; the scattering points can couple gauss light beams which have certain scattering angles and are emerged by the point light sources into light beams of which the light intensity is uniformly distributed, and the light beams with the lighting intensity uniformly distributed irradiate into the light conducting plate.

Description

Area source

[technical field]

The present invention is about a kind of light supply apparatus, especially about a kind of area source that is applied to LCD as even face light.

[background technology]

Present stage, LCD is fast because of its reaction time, display quality is preferable, radiationless, be applicable to advantages such as large-scale animation display, be widely used in notebook, desk-top computer monitor, workstation, industry monitoring device, Global Positioning System (GPS) (GPS), personal data processing, game machine, videophone, portable V CD, DVD and some other mancarried devices.Yet liquid crystal itself is not luminous, must have an area source to provide display image required light for it.And display panels is made up of a plurality of liquid crystal cells, and each liquid crystal cells is to the same requirement of having obtained of light, so this surface source luminescence briliancy must evenly distribute.Usually the light source in the area source has two kinds of line source and pointolites, the difference of light source character and position setting thereof, and the structural design thought of this area source is also with regard to corresponding difference.

Please see Figure 1, a kind of commonly used be that the area source 10 of light source includes the prism plate and diffuser plate (scheming not show) that a plurality of pointolites 13, a light guide plate 15, are attached at the reflecting plate (figure does not show) of light guide plate 15 bottom surfaces and are arranged at light guide plate 15 exiting surfaces with the pointolite.These a plurality of pointolites 13 are three light emitting diodes, evenly are spaced incidence surface one side in light guide plate 15 each other.The light that light guide plate 15 is sent pointolite 13 is converted into the area source outgoing.

In area source 10, because the emergent light as the light emitting diode of pointolite 13 is the Gaussian beam (Gauss Beam) with certain dispersion angle, its output intensity changes along with the change of emergent light angle, light intensity reaches maximum value near the outgoing zero angle, zero angle both sides light intensity diminishes gradually, then not having light beam in light guide plate 15 near the zone outside the LED source angle of divergence passes through, the zone that light beam intersects go out light intensity a little less than, make D among the figure, E, F, G zone briliancy deficiency, thus cause light guide plate 15 and area source 10 whole bright dipping luminance nonuniformities to be spared.

[summary of the invention]

The even defective of light guide plate bright dipping luminance nonuniformity when solving that area source utilizes pointolite as light source in the background technology the invention provides a kind of area source that light guide plate bright dipping briliancy is evenly distributed when utilizing pointolite as light source.

The technical scheme of technical solution problem of the present invention provides a kind of area source, and it comprises a plurality of pointolites, a light guide plate and a plurality of scattering point.This light guide plate comprises a light entrance face and one and the light-emitting face that intersects of light entrance face, these a plurality of pointolites are positioned light guide plate light entrance face one side, these a plurality of scattering points cave inward and are shaped in the light entrance face of light guide plate, and per at least three scattering points are corresponding to a pointolite, and the Gaussian beam of the certain dispersion angle of tool of this pointolite outgoing that is coupled becomes the equally distributed light beam of light intensity to go into to inject this light guide plate.

Area source of the present invention is provided with a plurality of scattering points of the light entrance face that is shaped in light guide plate of caving inward between light guide plate light entrance face and pointolite, the non-light guide plate that directly enters of the emergent light of pointolite, enter light guide plate but earlier the Gaussian beam of outgoing is converted into the even distribution light beam of light intensity from light entrance face through a plurality of scattering points, and each pointolite is all corresponding at least three scattering points on the light entrance face, these at least three scattering points are effectively for the dark space D that may occur in the background technology, E, F, the not enough problem of light intensity in the G zone compensates, and makes light guide plate and area source outgoing briliancy be evenly distributed.

[description of drawings]

Fig. 1 is the stereographic map of area source in the background technology.

Fig. 2 is the schematic perspective view of area source first embodiment of the present invention.

Fig. 3 is the vertical view of area source shown in Figure 2.

Fig. 4 is the vertical view of area source second embodiment of the present invention.

Fig. 5 is the diagrammatic cross-section of area source the 3rd embodiment of the present invention.

Fig. 6 is the diagrammatic cross-section of area source the 4th embodiment of the present invention.

[embodiment]

Please see Figure 2, it is first embodiment of area source of the present invention, this area source 20 includes a plurality of light emitting diodes 21 and a light guide plate 22, a plurality of scattering points 23 are arranged between these a plurality of light emitting diodes 21 and the light guide plate 22, and the diverging light of these a plurality of light emitting diode 21 outgoing that are coupled is injected in the light guide plate 22.

Light guide plate 22 roughly becomes the dull and stereotyped entity of a rectangular parallelepiped, its include a light entrance face 221, with the vertical light-emitting face 222 of light entrance face 221, bottom surface 223, first side 224, and first side, 224 second side surface opposite 225 and three side 226 relative with the plane of incidence 221.For making light from light-emitting face 222 even outgoing; usually be provided with a plurality of sites (figure does not show) in this bottom surface 223; this site can variformly distribute; and for improving the light utilization ratio; in this bottom surface 223 and this each side 224,225 and 226 also be coated with reflectance coating usually or attach one deck reflecting plate (figure do not show) again; return light guide plate 22 and, be coated with anti-reflective film to reduce the absorption loss of luminous energy with the light beam of reflection in this light entrance face 221 and light-emitting face 222 from light-emitting face 222 outgoing from light guide plate 22 bottom surfaces 223 or side outgoing.

Please see Fig. 3 in the lump, these a plurality of scattering points 23 are wire mark or the light entrance face 221 that is shaped in this light guide plate 22, and are outwards outstanding ball cross section body, certainly, these a plurality of scattering points 23 also can be the three-dimensional shape of the similar optical function of other tool, as right cylinder, four sides cylinder or Rotary-table etc.Per three scattering points are corresponding to a light emitting diode 21 in these a plurality of scattering points 23, and these three scattering point sizes are consistent, and corresponding with it light emitting diode 21 emergent lights of coupled in common are injected light guide plate 22 from light entrance face 221.

Please see Figure 4, it is the area source 40 of second embodiment of the invention, area source 20 compared to first embodiment, volume size distribution and light emitting diode 21 emergent ray intensity curves that its difference is wherein to correspond respectively to three scattering points 43 of a light emitting diode 21 distribute complementary, scattering point volume near corresponding light emitting diode 21 is less, and both sides are bigger away from the scattering point volume of corresponding light emitting diode 21.

Please see Figure 5, it is the area source 30 of third embodiment of the invention, these area source 30 basic structures are consistent with area source 20, and difference is that wherein a plurality of scattering points 33 are a plurality of ball cross section body, right cylinder, four sides cylinder or Rotary-table shrinkage pool or grooves that cave inward from light guide plate 32 planes of incidence 321.These a plurality of shrinkage pools or groove are the light entrance faces 321 that is shaped in light guide plate 32.Per three shrinkage pools or groove are corresponding to a light emitting diode 31 in these a plurality of scattering points 33, and these three scattering point sizes are consistent, and corresponding with it light emitting diode 31 emergent lights of coupled in common are injected light guide plate 32 from light entrance face 321.

Please see Figure 6, it is the area source 50 of four embodiment of the invention, area source 30 compared to the 3rd embodiment, its difference is that wherein three shrinkage pools that this corresponds respectively to a light emitting diode 31 or the volume size distribution and the light emitting diode 31 outgoing intensity curves of groove 53 distribute complementary, shrinkage pool or groove volume near corresponding light emitting diode 31 are less, and both sides are bigger away from the shrinkage pool or the groove volume of corresponding light emitting diode 31.

In the embodiment of the present invention, in light guide plate 22,32 light entrance face 221,321 with light emitting diode 21, be provided with a plurality of scattering points 23 between 31,33,

light emitting diode

21,31 emergent light is not directly to enter light guide plate 22,32, but earlier through a plurality of scattering points 23,33 Gaussian beams with outgoing are converted into the equally distributed light beam of light intensity from light entrance face 221,321 enter light guide plate 22,32, and each pointolite is all corresponding to three scattering points on the light entrance face, particularly second, in the 4th embodiment, scattering point 23, proper and the light emitting diode 21 of 33 volume size distribution, the Gaussian distribution complementation of 31 smooth outgoing intensity, these three scattering points are for the dark space D that may occur in the background technology, E, F, the not enough problem of light intensity in the G zone effectively compensates, thereby makes light guide plate 22,32 outgoing briliancy are evenly distributed.

Certainly, also available other pointolite of the light emitting diode among the present invention substitutes, and light guide plate also can be a wedge shape, and it is crossing that this wedge shape light guide plate and this rectangular parallelepiped tabular light guide plate difference are that its bottom surface and light entrance face acutangulate; Being somebody's turn to do can be more than three corresponding to the scattering point number of every bit light source, and its big or small deploying also is not limited to above-mentioned distribution, can decide according to the light-emitting characteristic curve of difference light source.This area source also can be in its at least one side further one-body molded or a plurality of scattering points of wire mark, and further be provided with a plurality of pointolites in side one side that light guide plate is provided with scattering point, consistent with first, second embodiment design, at least three scattering points of each pointolite correspondence, so, improving the light guide plate outgoing inhomogeneity while of briliancy, further improving the bright dipping briliancy of area source.

Claims

1. area source, it comprises a plurality of pointolites and a light guide plate, this light guide plate comprises a light entrance face and one and the light-emitting face that intersects of light entrance face, these a plurality of pointolites are positioned light guide plate light entrance face one side, it is characterized in that: this area source also includes and a plurality ofly caves inward and be and the integrated scattering point of light guide plate from this light guide plate light entrance face, and per at least three scattering points are corresponding to a pointolite, the Gaussian beam of the certain dispersion angle of tool of at least three scattering points coupling respective point light sources outgoing whenever becomes the equally distributed light beam of light intensity to go into to inject this light guide plate, and this volume size distribution and pointolite outgoing intensity curve of corresponding respectively at least three scattering points of same point light source distribute complementary, scattering point volume near the respective point light source is less, and both sides are bigger away from the scattering point volume of respective point light source.

2. area source as claimed in claim 1 is characterized in that these a plurality of scattering points are ball cross section body, right cylinder, four sides cylinder, Rotary-table shape shrinkage pool or groove.

3. area source as claimed in claim 1 or 2 is characterized in that this light guide plate further comprises vertical with light entrance face or acutangulates crossing bottom surface, and this bottom surface is provided with a plurality of sites.

4. area source as claimed in claim 3, it comprises that further one reflects the reflecting plate that returns light guide plate from light guide plate bottom surface emergent light.

5. area source as claimed in claim 3, this bottom surface further is coated with a reflectance coating.

6. area source as claimed in claim 1 or 2 is characterized in that this light guide plate further comprises another light entrance face, and one-body molded or wire mark has a plurality of scattering points on it, and whenever at least three scattering point correspondences are provided with a pointolite.

7. area source as claimed in claim 1 or 2 is characterized in that these a plurality of pointolites are light emitting diode.