CN202182339U

CN202182339U - Infrared transmission light source

Info

Publication number: CN202182339U
Application number: CN2011202352401U
Authority: CN
Inventors: 胡学娟; 阮双琛; 杨锦辉; 刘承香
Original assignee: Shenzhen University
Current assignee: Shenzhen University
Priority date: 2011-07-05
Filing date: 2011-07-05
Publication date: 2012-04-04
Anticipated expiration: 2021-07-05

Abstract

The utility model belongs to the field of optics and discloses a structure of an infrared transmission light source. The infrared transmission light source comprises a light guide plate and an infrared light source, wherein diffusion dots are printed on the light guide plate, the infrared light source is arranged on the side edge of the light guide plate, the position of the upper surface of the light guide plate, corresponding to the infrared light source, is adhered with an upper total reflection film, and a diffusion film is adhered to the position of the upper surface of the light guide plate, which is not occupied by the upper total reflection film; and a lower total reflection film is adhered to the lower surface of the light guide plate. The infrared transmission light source makes use of the infrared light source, the light guide plate on which the diffusion dots are printed, and the total reflection films to realize a light source structure with higher uniformity and simpler structure, the infrared transmission light source can be applicable to infrared imaging authentic identification of banknotes, the problem of non-uniform illumination of a conventional infrared light source is solved, and the infrared transmission light source also can be applicable to the transmission light source structures of other wavebands.

Description

A kind of infrared transmission light source

Technical field

The utility model relates to optical field, more particularly, relates to a kind of infrared transmission light-source structure.

Background technology

At present, the application of infrared transmission imaging is very extensive, like medical, shooting, false distinguishing etc.; But imaging effect is not ideal enough; With the bank note false distinguishing is example, because infrared transmission light source distance bank note is nearer, directly selects infrared LED array for use and does not add under the situation of other diffusion barriers; Be difficult to accomplish that illumination is even, this will have a strong impact on the quality of imaging.Thereby, the general now novel preferably area source of the uniformity---the LGP that adopts.

The major function of LGP is according to light principle at random, and the light that the spot light that concentrates on the edge or linear light source are sent is evenly distributed on the output face of LGP through the guiding of some special constructions, makes it to become area source.The design of LGP generally has wedges method, micro-structural method, adds diffusion point method and volume scattering effect method, and division is following:

Wedges method is to upset the reflection direction of light through the angle of inclination that changes the LGP surface, thereby light is transmitted from LGP;

The micro-structural method is that the upper and lower surfaces at LGP has added the direction of propagation that changes light like micro-structurals such as microprism, hemispheres, and light is transmitted from the LGP surface;

Add diffusion point method and be the form of high reflectance ink through the site is printed on bottom surface of light guide plate, forms diffusion point not of uniform size, that density unevenness is spared, light beam is propagated in the light guide plate mesh point all directions through scattering process;

Volume scattering effect method is the particulate that utilizes the LGP special material to be had, and in the space, is certain distributed, changes the light propagation trajectories.

The utility model content

The utility model technical problem to be solved is to provide a kind of infrared transmission light-source structure, is intended to make the bright dipping of light source more even, improves the infrared transmission imaging effect.

For solving the problems of the technologies described above; The technical scheme of the utility model is: a kind of infrared transmission light-source structure is provided; Comprise one be printed on the diffusion site LGP, be arranged on the infrared light supply on the side of said LGP; Be pasted with total reflection film at the upper surface of said LGP corresponding to the position of said infrared light supply, the upper surface of the said LGP position except that last total reflection film at least is pasted with diffusion barrier; Lower surface at said LGP is pasted with total reflection film down.

Further, said upward total reflection film is the aluminium film, and the part that following total reflection film is corresponding with said infrared light supply at least is the aluminium film.

Further, on said LGP, near the size of the diffusion site of said infrared light supply less than size away from the diffusion site of said infrared light supply.

Further, on said LGP, near the density of the diffusion site of said infrared light supply less than density away from the diffusion site of said infrared light supply.

Further, said infrared light supply comprises some infrared LED lamps; The side of said LGP is provided with some depressed parts; Said some infrared LED lamps correspondence one by one are located in said some depressed parts.

The utility model makes light propagate to all directions of LGP through printing diffusion site on the LGP of infrared light supply, and the upper surface of adding LGP posts diffusion barrier; Can make the emergent ray atomizing that becomes, it is poor to have reduced light and shade, has improved the uniformity of emergent light; Simultaneously, because the interreflection effect of total reflection film (like the aluminium film), its overwhelming majority to the light of LGP upper and lower surface scattering finally can be imported LGP from the side; Can improve the utilization rate of luminous energy, in addition, the effect of following total reflection film is with the light that penetrates from LGP lower surface reflected back LGP again; Improve the utilization rate of luminous energy, make output intensity bigger.Further, also can the density of the diffusion site on the LGP be designed according to the distance apart from infrared light supply with size, can make emergent light more be evenly distributed in the LGP surface.Above-mentioned infrared transmission light-source structure has been realized the higher and simpler light-source structure of structure of the uniformity, can be used for the false distinguishing of bank note infrared imaging, has solved the even problem of uneven illumination in general infrared transmission source, also can be applied to the transmitted light source structure of its all band.

Description of drawings

Fig. 1 is the sketch map of the infrared transmission light-source structure that provides of the utility model.

The specific embodiment

In order to make the utility model technical problem to be solved, technical scheme and beneficial effect clearer,, the utility model is further elaborated below in conjunction with accompanying drawing and embodiment.Should be appreciated that specific embodiment described herein only in order to explanation the utility model, and be not used in qualification the utility model.

Please with reference to Fig. 1, the infrared transmission light-source structure that the utility model provides can be used for the bank note projection imaging.This light-source structure is made up of diffusion barrier 1, diffusion site 2, LGP 3, last total reflection film 4, infrared light supply 5 and following total reflection film 6; Wherein LGP 3 can be processed by acrylic glass; Diffusion site 2 is the high reflectance ink lattice point structure that is printed on the bottom surface of LGP 3; Last total reflection film 4 is pasted on the upper surface of LGP 3 and corresponding with the position of infrared light supply 5; The upper surface that diffusion barrier 1 then sticks on LGP 3 is the position except that last total reflection film 4 at least, also can diffusion barrier be covered to the position at total reflection film 4 places certainly, and following total reflection film 6 is pasted on the lower surface of LGP 3.

Infrared light supply 5 is that the LED lamp of 850nm is formed by several wavelength; They are evenly distributed on the side of LGP 3; It is the structure that example shows infrared light supply 5 that Fig. 1 is distributed in 3 two long limits of LGP with the LED lamp; Wherein, the side of LGP 3 is provided with some depressed parts, and some infrared LED lamps correspondence one by one are located in said some depressed parts.LGP 3 adopts and adds the design of diffusion point method; Be about to high reflectance ink and form diffusion site 2 with the bottom surface that the form of net-point printing is printed on LGP, diffusion site 2 contains some micro-structures, and the light that the LED lamp of the lateral parts in infrared light source 5 sends is got to 2 last times of diffusion site; Scattering process will take place in light beam; Propagate to all directions of LGP 3, when the angle of light during less than the cirtical angle of total reflection, light will transmit from LGP 3 surfaces.In the present embodiment, near the part of infrared light supply 5 since light than comparatively dense, diffusion site 2 is designed for a short time and thin; Part away from infrared light supply 5 is more sparse owing to light; Diffusion site 2 is designed greatly and close; Promptly near the size of the diffusion site of infrared light supply 5 less than size away from the diffusion site of infrared light supply 5; And near the density of the diffusion site of infrared light supply 5 less than density, so light can be evenly distributed in LGP 3 surfaces away from the diffusion site of infrared light supply 5.

The course of work is described below: the light that the LED lamp sends is to the four sides scattering; But because the interreflection effect of last total reflection film 4; The final most of light of its light to LGP 3 upper and lower surface scatterings is injected LGP 3 from the side, and light gets into LGP 3 and gets to 2 last times of diffusion site scattering process will take place, and it makes all directions propagation of light to LGP 3; When the angle of light during less than the critical angle of total reflection, light will be from LGP 3 upper surface outgoing.Owing to design for a short time and thin, away from designing greatly and close in the part diffusion site 2 of light source, so light can be evenly distributed in LGP 3 surfaces near the Lights section diffusion site 2.Simultaneously, because the effect of the diffusion barrier 1 of upper surface, the emergent ray atomizing that becomes, it is poor to have reduced light and shade, has improved the uniformity of emergent light.The effect of the following total reflection film 6 below the LGP 3 is with the light that penetrates from LGP 3 lower surfaces reflected back LGP 3 again, improves the utilization rate of luminous energy, makes output intensity bigger.

In the present embodiment; Consider total reflection film 4 and following total reflection film 6 roles; With adopting reflective qualities higher aluminum films to realize with infrared light supply 5 corresponding parts at least in last total reflection film 4 and the following total reflection film 6, the remainder of following total reflection film 6 then adopts the comparatively cheap total reflection film of other cost to realize getting final product.

The above is merely the preferred embodiment of the utility model; Not in order to restriction the utility model; Any modification of being done within all spirit and principles at the utility model, be equal to replacement and improvement etc., all should be included within the protection domain of the utility model.

Claims

1. infrared transmission light-source structure; Comprise one be printed on the diffusion site LGP, be arranged on the infrared light supply on the side of said LGP; It is characterized in that; Be pasted with total reflection film at the upper surface of said LGP corresponding to the position of said infrared light supply, the upper surface of the said LGP position except that last total reflection film at least is pasted with diffusion barrier; Lower surface at said LGP is pasted with total reflection film down.

2. infrared transmission light-source structure as claimed in claim 1 is characterized in that, said upward total reflection film is the aluminium film, and the part that following total reflection film is corresponding with said infrared light supply at least is the aluminium film.

3. infrared transmission light-source structure as claimed in claim 1 is characterized in that, on said LGP, near the size of the diffusion site of said infrared light supply less than size away from the diffusion site of said infrared light supply.

4. infrared transmission light-source structure as claimed in claim 1 is characterized in that, on said LGP, near the density of the diffusion site of said infrared light supply less than density away from the diffusion site of said infrared light supply.

5. infrared transmission light-source structure as claimed in claim 1 is characterized in that, said infrared light supply comprises some infrared LED lamps; The side of said LGP is provided with some depressed parts; Said some infrared LED lamps correspondence one by one are located in said some depressed parts.