Abstract
Whenever a laser specialist or an engineer employs a spreadsheet and compare and plot laser MPEs with broad-band limits, they see apparent differences and disconnects that can be quite puzzling. This is a particular concern of those trying to assess the optical risks of viewing bright LEDs. The rationale behind the two sets of exposure limits necessarily differ. For a laser, only the hazards at a wavelength of interest are reflected in the MPE, and competing hazard mechanisms lead to, at most, two limits, or "dual limits." However, with broad-band lamp sources, at least five different potential hazards must be assessed. The default source size for lasers is a "point" source defined by alpha-min; whereas, the default source size for incoherent sources is a large source and alpha-max. Thus laser limits can be expressed as irradiance, and broad-band limits as radiance limits to protect the retina. A rapidly closing pupil is dealt with differently in the two different sets of limits, leading to what appear to be "discontinuities. " There may be some cases where laser limits are easier to apply to a nonlaser, monochromatic point-source, such as superluminescent diodes, and incoherent source limits to some large-source laser displays.
Original language | English (US) |
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Title of host publication | International Laser Safety Conference: The World's Leading Conference on Laser Safety, ILSC 2007 |
Pages | 273-280 |
Number of pages | 8 |
State | Published - 2007 |
Externally published | Yes |
Event | 2007 International Laser Safety Conference, ILSC 2007 - San Francisco, CA, United States Duration: Mar 19 2007 → Mar 22 2007 |
Other
Other | 2007 International Laser Safety Conference, ILSC 2007 |
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Country/Territory | United States |
City | San Francisco, CA |
Period | 3/19/07 → 3/22/07 |
ASJC Scopus subject areas
- Safety, Risk, Reliability and Quality