Photopic vision
- Photopic vision
Photopic vision is the vision of the
eye under well-lit conditions. In humans and many animals, photopic vision allows color perception, mediated bycone cells .The human eye uses three types of cones to sense light in three respective bands of color. The
biological pigment s of the cones have maximum absorption values at wavelengths of about 420 nm (blue), 534 nm (Bluish-Green), resp. 564 nm (Yellowish-Green). Their sensitivity ranges overlap to provide vision throughout thevisible spectrum . The maximum efficacy is 683 lumens/W at a wavelength of 555 nm (green). [cite book|url=http://books.google.com/books?id=CU7-2ZLGFpYC&pg=PA467&dq=683+luminous+efficacy&ei=n3yvR_mrCJGgygSI2-ydBg&ie=ISO-8859-1&sig=cn1Fw0s76sQo2H7BhMyhuzmEc8E#PPA467,M1| title=The Focal Encyclopedia of Photography|editor=Leslie D. Stroebel, Richard D. Zakia|publisher=Focal Press |first=J.|last=Pelz|isbn=0240514173|edition=3E|year=1993|page=467]The human eye uses
scotopic vision under low-light conditions, andmesopic vision in intermediate conditions.ee also
*
Candela
*Purkinje effect
*Photometry
*Photosensitive ganglion cell References
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Look at other dictionaries:
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