LPF Donation via Stripe | LPF Donation - Other Methods
Links below open in new window
ArcticMyst Security by Avery
The Trail of a Newcomer (475 mW and Questions)
- Thread starter Swesent
- Start date
- Joined
- Oct 25, 2008
- Messages
- 128
- Points
- 0
Since nobody answered your question #4, I'll take a stab.
Basically air (normal air) transmits visible light very good - soo good, in fact, that it makes it from the sun to here! As shown here: http://en.wikipedia.org/wiki/Image:Solar_Spectrum.png there are some wavelengths that air (actually the moisture in air) will absorb light. But, aside from these, basically the transmission is 99.99% or better! Because the beam diverges, the power density gets less and less, though. So, at 3 miles, the power is basically the same. Optics (like mirrors, etc) have wavelength dependent transmission/reflection due to the material properties. Even plain glass reflects about 10% of the light.
K
Basically air (normal air) transmits visible light very good - soo good, in fact, that it makes it from the sun to here! As shown here: http://en.wikipedia.org/wiki/Image:Solar_Spectrum.png there are some wavelengths that air (actually the moisture in air) will absorb light. But, aside from these, basically the transmission is 99.99% or better! Because the beam diverges, the power density gets less and less, though. So, at 3 miles, the power is basically the same. Optics (like mirrors, etc) have wavelength dependent transmission/reflection due to the material properties. Even plain glass reflects about 10% of the light.
K
