Patent ID: 7858873

Claim:
A photovoltaic cell, comprising: a photo-electric conversion layer having a front surface and a rear surface; and a reflection layer provided on the rear surface of the photo-electric conversion layer, wherein the reflection layer includes transparent layers of a first material having a refractive index substantially ranging from 1.45 to 1.65 and of a second material having a refractive index substantially ranging from 1.70 to 1.90 which are alternately stacked in a total number substantially ranging between 50 and 500, each of the transparent layers having a thickness substantially ranging between 50 nm and 160 nm, wherein the transparent layers are formed from an organic polymer material, and wherein the reflection layer has a reflectivity of 95% or higher for light wavelengths substantially ranging between 400 nm and 1100 nm, so that when light is incident from the front surface of the photo-electric conversion layer, the reflection layer reflects a part of the incident light having wavelengths substantially ranging between 400 and 1100 nm back into the photo-electric conversion layer.