What is "photopsin"

n. (context protein English) Any of a class of photoreceptor proteins present in the cones of the retina

Photopsins (also known as Cone opsins) are the photoreceptor proteins found in the cone cells of the retina that are the basis of color vision. Iodopsin, the cone pigment system in chicken retina, is a close analog of the visual purple rhodopsin that is used in night vision. Iodopsin consists of the protein component and a bound chromophore, retinal.