Search for crossword answers and clues
The luminous flux incident on a unit area
Answer for the clue "The luminous flux incident on a unit area ", 11 letters:
illuminance
Alternative clues for the word illuminance
Word definitions for illuminance in dictionaries
Wikipedia
Word definitions in Wikipedia
In photometry , illuminance is the total luminous flux incident on a surface, per unit area . It is a measure of how much the incident light illuminates the surface, wavelength-weighted by the luminosity function to correlate with human brightness perception. ...
Wiktionary
Word definitions in Wiktionary
n. (context physics English) The luminous flux incident on unit area of a surface; measured in lux or lumens
WordNet
Word definitions in WordNet
n. the luminous flux incident on a unit area [syn: illumination ]
Usage examples of illuminance.
Thus a reflectance change shows itself as step edge in an image, while illuminance changes gradually over space.
By this argument one can separate reflectance change from illuminance change by taking spatial derivatives: High derivatives are due to reflectance and low ones are due to illuminance.
The luminance image can be considered to be the product of two other images‚ the reflectance image and the illuminance image.
This must mean that illuminance and reflectance images are not arbitrary functions.
The vertical spine appears to be a dihedral with different illuminance on the two sides.
Again, the configuration and gray levels suggest that illuminance is the cause.
Then, under a given illuminance, one would observe a distribution of luminance samples such as that shown in figure 24.