On Fri, 16 Dec 2005 11:38:05 -0700 Tom Reynolds <[EMAIL PROTECTED]> wrote:
> I know that in aircraft a "night light" is usually a red light. I'm not > going to get into wavelengths or anything, other than to note that I > think red light has a very short wavelength and blue is long-er than > red. How much longer, if it makes any difference, why (or why not) is > something I'll leave up to an optometrist, physicist (if someone studies > physics, why isn't that person a "physician...?") and the like. I'm a physicist; my Dad's a physician... Red light has a longer wavelength than blue light. The wavelength of red light is nearly twice as long as the wavelength of blue light. Red light affects your night vision less than blue light. Astronomers have flashlights with red filters. Craig
