# Sensitivity of eye

In which color human eye is most sensitive?

• An additional question: what is the quantum efficiency of the eye? – nibot Jan 17 '11 at 16:27

## 2 Answers

Around 555nm wavelength - green color. That's why green lasers are soo cool even at 10 mW :-D

• you can put that link in a ![alt text](http://upload.wikimedia.org/wikipedia/commons/e/e9/Eyesensitivity.png) construct to have it shown here directly – Tobias Kienzler Jan 17 '11 at 15:40

Answer to the additional question: "what is the quantum efficiency of the eye?" I remember old studies reporting that eight photons reaching the photoreceptors can be detected by a human observer as a flash of light in certain laboratory conditions. The more normal range would certainly be lower than 0.125 say 0.05 - 0.01. Cooling down laboratory animals thus reducing thermal noise in the retina enhances sensitivity but means longer integration times and lower spatial and temporal resolution.