more,
the sensistivity of photodetectors is a function of the frequency of the
light impinging on it. i have no idea which detector you are using but they
have specs that tell you this. the total signal out of the photodetector
adds up the signal generated by the entire spectrum of the light impinging on
it. the voltage (or current for a photomultiplier tube) produced is a sum
over all of the light from a flashlight and since this is essentially white
light it probably covers the entire response function of the sensor. on the
other hand integrating (or suming) over the laser output results in output at
the very few frequencys produced by the laser. take an example of light from
say 4500 angstroms to 9000 angstroms, for flashlights (these are really black
body radiators and have a spectrum of their own) you have a "multiplier" of
4500, assuming a flat response. for the laser the spectrum is probably a few
angstroms wide say 10. the difference in output signal just from this is 450.
does this help?
pmc