Photo IC has spectral response close to human eye sensitivity. Two photosensitive areas are made on a single chip. Almost only the visible range can be measured by finding the difference between the two output signals in the internal current amplifier circuit. Compared to the previous type it offers lower output fluctuations for light sources producing the same illuminance at different colour temperatures. Encapsulated in a plastic package having the same shape as a metal package.

Spectral response close to human eye sensitivity is attained without using visual-compensated filter.
Operation just as easy to use as a photodiode
Lower output-current fluctuations compared with phototransistors and CdS photoconductive cells.
Excellent linearity
Low output fluctuations for light sources producing the same illuminance at different colour temperatures