A kind of led secondary catadioptric lens for direct type backlight source

Abstract

The invention discloses an LED secondary catadioptric lens used for a direct-type backlight source. The LED secondary catadioptric lens is an axisymmetric entity made of transparent materials, and is characterized in that the LED secondary catadioptric lens is an axisymmetric entity made of a transparent material. The lens is composed of an incident refraction surface, a central reflection surface, a side exit surface, and a bottom reflection surface. The incident refraction surface, the central reflection surface, the side exit surface, and the bottom reflection surface are all curved surfaces. In the lower part of the reflective lens, the central reflective surface is connected to the side exit surface to form an upper surface, the central reflective surface is located above the incident refraction surface, and the side exit surface is a curved surface connecting the bottom reflective surface and the central reflective surface. The curved surfaces in the present invention can be characterized by quadratic polynomials. The invention has simple structure, reduces diffusion distance and has no dispersion phenomenon while realizing large-angle illumination and not increasing the number of LED particles. The invention is simple in installation and configuration, and can effectively save energy.

Description

Technical field [0001] The invention relates to an LED double catadioptric lens used for a direct type backlight light source, which is mainly suitable for the backlight source of a direct type backlight light source, an LED backlight advertising board and the like. Background technique [0002] The backlight light source has a large number of applications in traditional liquid crystal displays (LCD) and large advertising boards. The traditional cold cathode tube (CCFL) backlight has been gradually replaced by the light emitting diode (LED) backlight. The original backlight is realized by a light guide plate with a carved pattern on the back. The light source (CCFL for line light source or LED for point light source) leads light from the side of the light guide plate. This method is not efficient due to the limitation of the light guide plate technology. The direct-lit LCD backlight effectively improves the problem of light efficiency. LEDs are point light sources with limited-...

AI Technical Summary

Problems solved by technology

However, due to the dispersion factor of the lens material itself in this solution, when the refraction angle is too large, the difference in refraction angle between different wavelengths is also greater, thus causing a rainbow phenomenon, that is, the generation of color spots affects the white chromaticity of the light source, making this backlight The solution cannot meet the requirement of further reducing the light mixing height without increasing the number of LED particles

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