Grating structure for dividing light

Patent metadata

Field	Value
Publication number	US-9500785-B2
Application number	US-201414169656-A
Country	US
Kind code	B2
Filing date	Jan 31, 2014
Priority date	Dec 15, 2009
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

A grating structure and a solar cell assembly. In one aspect, the grating structure suppresses the zero order transmission to near 0%. In another aspect, the solar cell assembly has improved absorption due to coupling with a grating structure.

First claim

We claim:

1. A solar cell assembly comprising:
an absorption layer for absorbing light and converting the light into electrical energy;
a first grating layer formed by alternating portions of a first lossless dielectric formed directly on the absorption layer and a second lossless dielectric formed directly on the absorption layer, the first grating layer having a thickness of about 0.12λ and a period of about 0.32λ; and
a second grating layer disposed on a second side of the absorption layer, the second side being opposite the first side, the second grating layer having a thickness of about 0.12λ and a period of about 0.32λ;
wherein the first grating layer, the second grating layer, and the absorption layer form a sandwich structure, the absorption layer being located between the first layer and the second layer.

2. The solar cell assembly according to claim 1 , wherein the second grating layer comprises lossless dielectrics.

3. The solar cell assembly according to claim 1 , wherein the second grating layer is formed by alternating portions of the first lossless dielectric and the second lossless dielectric.

4. The solar cell assembly according to claim 3 , wherein the first lossless dielectric has a different permittivity than the second lossless dielectric.

5. The solar cell assembly according to claim 4 , wherein the first lossless dielectric has a permittivity of about 2.25 and the second lossless dielectric has a permittivity of about 6.25.

6. The solar cell assembly according to claim 1 , wherein the absorption layer has a thickness of less than ⅛ a wavelength range of light (λ).

7. The solar cell assembly according to claim 6 , wherein the absorption layer has a thickness of about 3/32λ.

8. The solar cell assembly according to claim 3 , wherein the first portion comprises fused silica and the second portion comprises titanium dioxide.

Assignees

• Toyota Motor Eng And Mfg North America Inc
• Univ Pennsylvania
• Toyota Central Res And Dev Laboratories Inc
• Toyota Motor Eng & Mfg North America Inc

Inventors

• Iizuka Hideo
• Engheta Nader
• Takeda Yasuhiko

Classifications

• G02B5/18 Primary

  Diffraction gratings {(holographic optical elements G02B5/32, G03H; integrally combined with optical fibres G02B6/02057; for coupling light guides G02B6/34; integrally combined with optical integrated light guides G02B6/12; grating systems G02B27/44)} · CPC title

• G02B5/1833 Primary

  comprising birefringent materials (birefringent elements per se G02B5/3083) · CPC title

• G02B5/1857

  using exposure or etching means, e.g. holography, photolithography, exposure to electron or ion beams · CPC title

• H01L31/02168

  Electricity · mapped topic

• H01L31/0236

  Electricity · mapped topic