[Laser] range of pointer?

[Charles Pooley]

  Chuck Hast <wchast at gmail.com> wrote:
   
 >On 1/24/07, ridwan arifin wrote:
>> i'm using a laser pointer ~670nm 4.5V for sinding
>> serial data. i wanna know the maximum distance that
>> ican reach with the laser. and the beam pattern....
>>
>At what data rate?
  -------------------------
   
  Across the inner Solar System if you can settle for a low data rate 
and use photon counting (geiger mode APD or PMT).
   
  30 mw at 650 mn is just about 10e17 photons/sec, and if confined to 2 
arc-sec (10e-5 radian) the signal from 1 AU can be over 10e4 per sec 
depending on telescope size.
   
  From lunar distance much higher data rates are possible.  The system 
for 
this is part of the Microlauncher system I am trying to get started.
   
      Charles Pooley
    ckpooley at sbcglobal.net
    661 824-4095
    www(dot)microlaunchers(dot)com