Centering a Laser Beam received from multiple directions

[Dohmer]

Is it possible to set mirrors up in such a way that if you hit any area of any of the mirrors, the laser would be brought to a central location in the middle of the mirrors? I'm thinking of a way to transmit data in space via laser where you would want a large target for the laser to hit when sending information back and forth between satelites. The laser would hit the array from up to a wide angle (say <90°).

thank you so much. i have already put a fair amount of thought into this.

 

[DoItForYourself]

What about a big paraboloid mirror?

 

[Dohmer]

What about a big paraboloid mirror?

Right, I was trying to think of a configuration. Maybe it is just a matter of coming up with an algorithm so that any area of a 'target' that you hit would allow the laser to be centered. A paraboloid mirror by itself would only have a very small region where the laser would hit the center, plus we have to remember the laser is moving a lot as well (assume the laser is in a higher Earth orbit).

 

[berkeman]

Is it possible to set mirrors up in such a way that if you hit any area of any of the mirrors, the laser would be brought to a central location in the middle of the mirrors? I'm thinking of a way to transmit data in space via laser where you would want a large target for the laser to hit when sending information back and forth between satelites. The laser would hit the array from up to a wide angle (say <90°).

thank you so much. i have already put a fair amount of thought into this.

Right, I was trying to think of a configuration. Maybe it is just a matter of coming up with an algorithm so that any area of a 'target' that you hit would allow the laser to be centered. A paraboloid mirror by itself would only have a very small region where the laser would hit the center, plus we have to remember the laser is moving a lot as well (assume the laser is in a higher Earth orbit).

I don't think the parabolic antenna is a solution to what you are asking about. It sounds like you are wanting a way to aim fairly collimated lasers between several satellites and having good TX/RX gain between them. Parabolic antennas are not for receiving off-axis signals.

I think you will need to use a TX/RX pair for each communication path if they are not coaxial with the other paths. There may be a way to receive laser signals from multiple directions at once, but the signal-to-noise ratio will be pretty bad if you are receiving light from all around, just in order to be able to receive signals from a few discrete directions.

 

[Dohmer]

I don't think the parabolic antenna is a solution to what you are asking about. It sounds like you are wanting a way to aim fairly collimated lasers between several satellites and having good TX/RX gain between them. Parabolic antennas are not for receiving off-axis signals.

I think you will need to use a TX/RX pair for each communication path if they are not coaxial with the other paths. There may be a way to receive laser signals from multiple directions at once, but the signal-to-noise ratio will be pretty bad if you are receiving light from all around, just in order to be able to receive signals from a few discrete directions.

The question is what kind of Rx can you set up to receive the laser transmission. it would be incredibly difficult to center this light on a Rx

 

[berkeman]

The question is what kind of Rx can you set up to receive the laser transmission. it would be incredibly difficult to center this light on a Rx

To have good optical receive gain, you use something that looks like telescope optics. Those optics can either be made up of lenses or parabolic mirrors, or a combination. But telescope optics have a very finite entrance pupil, and do not receive optical signals that are off-axis. So as long as the Tx laser beam source is enough on-axis to be received by the Rx optics, you get a good Rx signal. But if your Tx beam is way off axis (even a few degrees, depending on your optical gain), you will not see that beam.

http://www.a-levelphysicstutor.com/images/optics/tels-Newtonian.jpg

 

[Dohmer]

I believe what I will try to do is have 2-3 (or more) convex lenses where rapid adjustment of the middle lense will need to occur. I wonder if the temperature or level of radiation of the laser will affect all types of lenses. Also, if I were to have a say 20 meter lens, I wonder what the lightest weight lense I could have would be...