Surface light source unit and device using the unit

Abstract

Glaring and uneven luminance on a screen is limited when used for image displaying for a liquid crystal display unit or the like. A surface light source unit comprising a light emitting unit (22) using an LED or the like, and a light guide plate (23) for guiding light emitted from the light emitting unit (22) to spread it over the entire light output surface, wherein many deflection patterns (34) are provided on the rear surface of the light guide plate (23), and the deflection patterns (34) are used for reflecting a light in the light guide plate (23) to enable the light to be outputted from the light outputting surface of the light guide plate (23). When a polar coordinate using as the origin the center point set in the vicinity of one corner of the light guide plate is assumed, a location point (Rm, thetam) of a deflection pattern (34) is expressed in the following expressions (Ro > 0). Rm= Rm-1 + (1 / Rm-1) thetam= thetam-1 + 137.5 DEG.

Description

technical field [0001] The present invention relates to a surface light source device and an apparatus using the same, and more particularly to a surface light source device used as a backlight or a front light, an illumination device, etc. in an image display unit. Also, the present invention relates to an apparatus using the surface light source device. Background technique [0002] figure 1 and figure 2 are an exploded perspective view and a sectional view showing a surface light source device having a general structure. The surface light source device 1 is used as a backlight, and includes a light guide plate 2 that confines light, a light emitting part 3 and a reflection plate 4 . The light guide plate 2 is formed of a transparent resin such as polycarbonate resin, methacrylic resin, etc., and has a high refractive index. The diffusion pattern 5 is formed on the lower surface of the light guide plate 2 by letterpress processing, dot printing of diffusion and reflec...

AI Technical Summary

Problems solved by technology

[0012] However, using the Figure 8 The layout shown, creates gaps in the peripheral area in the circle, and the space is wasted

Also, using the Figure 9 With the layout shown, the light emitting components 20 are made entirely at uniform angles in a particular direction, so that the emission of light in a particular direction is pronounced, not uniform and visually unsightly

In this way, with conventional lighting lamps and pilot lights, it is difficult to uniformly arrange the light emitting parts 20 such as on a circle and to manufacture a lamp in which the light emitting points are uniformly aligned and looks good.

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