Polarization white light LED based on fluorescent ceramic and double-layer nanometer grating structure

Abstract

The invention discloses a polarization white light LED based on fluorescent ceramic and a double-layer nanometer grating structure. A working wave band is modulated according to a structure parameter, wherein an extinction ratio is higher than 20dB and TM wave transmittance is higher than 60% in a visible light range of 450nm-650nm. According to the polarization white light LED, a low-refractivity transition layer is introduced on the surface of a fluorescent ceramic substrate. The transition layer improves effect of the device and furthermore prevents metal etching, so that higher convenience and higher speed in a manufacture process. Furthermore a composite structure which comprises a dielectric grating and double-layer metal is integrated on the surface of the transition layer. The composite structure is coupled with blue light GaN-based LED, and polarization white light emission is finally realized. The transition layer and a dielectric layer grating are made from semiconductor materials of magnesium fluoride, silicon dioxide, PMMA, etc. The nanometer grating is made from metal materials of aluminum, silver, gold, etc.

Description

technical field [0001] The invention relates to the preparation technology of optical elements, in particular to the design and preparation method of a GaN-based polarized white light LED based on fluorescent ceramics and a double-layer nano grating structure. Background technique [0002] With the continuous aggravation of global energy problems, energy conservation and environmental protection have gradually become the development theme of countries all over the world. LED (light emitting diode) has the characteristics of high luminous efficiency, less pollution, and energy saving, and has shown great advantages in many applications. As a light source, white light diode (LED) is widely used in the fields of solid-state lighting, liquid crystal display, and automobile headlights due to its high luminous efficiency and long life. The larger the value, the more promising the application prospect. [0003] While white LEDs are developing day by day, polarized white light sou...

AI Technical Summary

Problems solved by technology

(1) Doping magnetic elements into the material system can directly generate polarized light, but the difficulty of doping is relatively large, and it is difficult to realize; (2) It can be grown in semi-polar or non-polar GaN-based LEDs are directly grown on the surface to obtain polarized light, but the manufacturing process of this kind of polarized LED is complicated, the material growth is difficult, and the extinction ratio of polarized light is not very high; (3) The nano-optical structure is integrated on the surface of the LED chip to realize polarized light

The realization of polarized white light in the OLED field is mainly through the mixing of some organic substances. These organic substances have special properties under specific temperature conditions to produce polarized white light. Often this kind of polarized white light has a relatively low degree of polarization, and there are also certain problems in thermal stability. There is still a long way to go for practical industrial applications; and if the white light polarization of the OLED itself is not considered, the external design structure to achieve white light polarization output will greatly help the improvement of the degree of polarization, but it is still a little bit difficult for actual production applications. significantly complicated

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