Defects in the light transfer rate of the light guide plate are caused by the following technical deficiencies. The light guide plate (1) both sides are smooth, light intensity and both sides of the transmission such as large amount of exposure to light on the value of the brand theory is only half of the incident light, and with increasing distance away from the light source, the brightness decreases obviously; (2) the light inlet is provided with an ejector rod position so, the incident surface, the formation of diffuse reflection of light, resulting in substantial amount of incident light into the guide plate decreased; (3) without reflex arc light transmission and frosted surface, due to repeated light reflection and refraction phenomenon, and greatly increases the enters into the light guide plate loss of light; (4) the mold parting surface, and disposed on the front end of the incident light, the incident light into the light guide plate is like a wall. (5) inconsistent with the direction of optical fiber cable transmission. As a result, the overall light guiding performance of the utility model is much lower than that of imported similar parts, so that when the instrument is illuminated, one side of the lamp is bright and dark, or the brightness of the illuminating bulb can not be increased, and the brightness can not be increased.
Through the process of comparison of the above two kinds of typical LGP parts of the analysis, the design process of this kind of parts should note the following points: (1) pay attention to open mold gate location and the incident light mouth positions, the fiber direction formed the material flow and optical transmission direction; (2) notice as far as possible to reduce the light reflection times, transition with 45 degrees right angle reflector, such as arc should be frosted on both sides; (3) the mold parting surface design does not affect the light transmission principle; (4) to reduce the light emission, the light guide plate on the back grinding processing, the formation of diffuse reflection, ensure soft light lighting for the traditional instrument side light illumination, due to lack of the congenital, so through the way of lighting a launch, which was quickly eliminated. But through the lighting mode, due to the lack of knowledge of improved optical design and structure, only pay attention to increase the design work of the light guide plate, the light not only from the table behind the brand through for lighting, but also from the side of the table plate leaking into the gap, forming the soft glare effect, seriously affect the instrument through the advantages of soft light lighting itself.