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Several participants work with or have experience with LEDs. Not surprisingly, they are one of the “hottest” topics around. Because LEDs are directional emitters (as opposed to blackbody radiators) their output measurements must be conducted differently. There has been some discussion here about the correct way to account for output as a function of angle. How do we account for the total output? And what quantity might we be measuring?
Design, or elaborate upon, a test setup for LEDs that will allow total output (including the name of the relevant radiometric or photometric quantity) and directional output. Can you estimate the uncertainty in your results? What kind of signal magnitude do you expect for a particular LED or LED type? Visual aids such as graphs and drawings are appreciated.
http://www.nist.gov/pml/div685/grp03/spectroradiometry_spectral.cfm
http://www.ledsmagazine.com/index.html
