On 30 Jun 2005 13:24:55 -0500, wrote:

When you superpose two 100w coherent laser beams, the resultant
power is indeed 400w

This is correct if the two beams are coherent and have the
same polarization. Very hard to do at optical frequencies, much
easier at lower frequencies.

Hi Tor,

We've seen the math pencil-whipped both ways now to cover all the
available answers. The devil's in the details that are not found in:
Itot = I1 + I2 + 2*Sqrt(I1*I2)cos(theta)
not to mention the glaring mistakes of the first posting of this
formula.

This is like quoting Einstein's E = MC² (anyone with a Xerox can do
that) and not knowing how much energy it takes to get 100 joules of
green illumination out of a bare lightbulb.

73's
Richard Clark, KB7QHC