The SGF Laser Ranging 50cm CassegrainTelescope

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The Cassegrain Reflector, probably
invented by Laurent Cassegrain.

The optical pathway of the SGR telescope.

The main laser ranging telescope at SGF is a 50cm Cassegrain type. This kind of telescope uses a convex secondary mirror to bounce the light back through a hole in the main mirror letting the light to reach an eyepiece at the rear of the telescope, as oposed to the similar Newtonian type which has an angled mirror sending the light to a side mounted eyepiece.

There are four main areas of inrerest, roll over the green boxes to find out more:

  1. The low light wide angle camera
  2. The emitter telescope
  3. The Day time camera
  4. The C-SPAD photon detector.
SLR laser transmission optics C-SPAD