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Portable Laser Pointers - Industry Insight

My purpose is ONLY focused upon the visual efficiencies of these portable laser diode pointers. The theory of operation can be obtained from a common Internet Search Engine such as BING.

Out of the many laser pointers on the market; only the
GREEN @ 532nm laser pointer is the most effective for live presentations before an audience. These are the properties that make them the most appropriate choice:

Diode Laser Pointer @ 532nm wavelength:

The 532nm wavelength has the greater absorption by the eye's retina.
Less laser luminous energy is required to produce an effective laser pointer.
Most utilize 2 or 3 AAA or AA battery cells.
Possess a LONG operating lifetime under normal use.
Are robust, durable and economical for commercial presentation use.
A 20mW output power is MORE that sufficient for large auditoriums and conference rooms.
Safety recommendations call for a maximum output limit of only 5mW (see reference 3).

Advisory CAUTION Notes:

These are NOT toys! They must NOT be handled by minors.
NEVER point the device into the eyes of ANY living being.
Using these for illuminating aircraft is a serious CRIMINAL offense.
Users MUST be thoroughly familiar with the PROPER utilization of this device.
These devices MUST NOT be utilized beyond their INTENDED and SPECIFIED purpose.
DO NOT hinder, modify nor defeat any safety nor regulated operational feature.

References:

1. FDA Guidelines for Laser Pointer Manufacturers
2. Laser Pointers - Laser Institute of America (LIA)
3. Safety Recommendations for Laser Pointers - Rockwell Laser Institute (RLI)
These are NOT toys!
Laser Pointers are
DANGEROUS
21 CFR 1040.10
The GREEN Laser wavelength @ 532nm is absorbed more readily by the retina than any other visible laser wavelength as shown by this Cone Response Graph.
532nm (GREEN) Diode Laser wavelength has the greater Photopic Luminous Efficiency.