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6 terms
Photonics Dictionary: F
Clear All Filters x
luminance x
F x
Fechner ratio
The differential luminance threshold divided by the luminance.
Ferry-Porter law
The law stating that the critical fusion frequency is approximately proportional to the logarithm of the luminance and the area.
flicker photometry
Heterochromatic photometry that depends on the elimination of chromatic flicker at a lower frequency than luminance flicker.
footcandle
Unit of illuminance equal to one lumen per square foot. (fc).
footlambert
Unit of luminance equal to 1/p candela per square foot. (fl).
foveal vision
->
photopic vision
Vision by means of retinal cones; color vision. Relatively high levels of luminance are required for photopic vision.
Photonics Dictionary
F
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