Samsung patent application US20160054172 "Image sensor for producing vivid colors and method of manufacturing the same" by Sookyoung Roh, Sunghyun Nam, Seokho Yun, and Hongkyu Park proposes a color splitter to improve sensitivity of image sensor:
"Although organic dye color filters are widely used in color image sensors, such organic dye color filters absorb light in all but one certain wavelength band. Therefore, using such color image sensors may cause a relatively large amount of light energy loss and a low light efficiency."
So, a color separating beam splitter is proposed. The splitter is made of high refractive material diagonal stripe located inside a low refracting material layer:
Apparently, the simulation show quite high efficiency of the proposed color division scheme comparing with the traditional die based CFA: