Photoconduction and semiconduction in dried receptors of sheep eyes

Abstract

Both photoconduction and semiconduction have been measured in dried sheep rods. The semiconduction activation energy is 2.3 e.v. The photocurrent decreases under prolonged irradiation and shows a slight recovery in the dark. This is related to the photoisomerization of rhodopsin. The photoconduction excitation spectrum was roughly determined to correspond to absorption in the α and β bands of rhodopsin. These results are in good agreement with the photoconductive theory of the visual receptor process.