Most use red because it is the least expensive. A blue laser though will have 9.4 times as much scattering as a red though because of the shorter wavelength of the light (scattering varys inversely to the 4th power of the wavelength of the light. Also the scattering (tyndall effect) goes up to the 4th power of the particle size, or the square of the particle area.
A very good site on the math of Rayleigh Scattering is at http://hyperphysics.phy-astr.gsu.edu/hbase/atmos/blusky.html Marshall Pat wrote: > I just found out laser pointers come in different colors. Which > should I buy? Also, are the $3 ones the same as the $30 ones as far > as the light? > Thanks, Pat > > __________________________________________________ > Do You Yahoo!? > Tired of spam? Yahoo! Mail has the best spam protection around > http://mail.yahoo.com
