Photometrics Flashcards
What are the 5 terms commonly used in the quantification of light?
Luminous Intensity
Luminous Flux
Illuminance
Luminance
Luminous Exitance
What is the abbreviation of candela?
cd
One ___ represents the luminous intensity from a source point in a specific direction, on a solid angle called the steradian
Candela
“__” abbreviation for luminous intensity
l
This represents ____ ____
indicates the total amount of illumination emitted by a source
“F” is the abbreviation
Measured in lumens (lm)
Luminous Flux
“F” is the abbreviation for?
Luminous Flux
These all represent ______
used to determine the total amount of light on a surface
Abbreviation for illuminance is “E”
measured in lux (lx) or footcandles (fc)
typically assumed to be at workplane height
true illuminannce values vary with variety of task and age and other variables
Thus the recommendations are only a start
Illuminance
These represent ____
indicatest the amount of light in the eyes of users after reflection or transmission from a surface
Illuminance and reflectance affect luminance
the unit of measurement is candela per square meter (cd/m^2)
“L” is the abreviation
Lumiance
How high should a footcandle be?
30”
____ ___ represents these
indicates the toal quantity of light that is reflected and emitted in all directions from a surface or material
Measured in lumens per square foot (lm/ft^2)
Luminance exitance
____ is the location of a light source
Nadir
____ ____ indicate intensity expressed in candelas
Concentric
_____ _____ are the angles of ditribution
Radiating lines
_____ is the science that measures light
Photometry
the quantitative aspect of lighting is considered through recommended ______ values and standards
illuminance
