THREE MIRROR TELESCOPE DESIGN (URGENT)

CAN ANYONE TELL ME HOW TO CALCULATE

1. DISTANCE BETWEEN MIRRORS
2. OPTICAL PATH DIFFERENCE OF A TELESCOPE

WHAT IS DIFFERENTIAL RAY TRACING TECHNIQUE AND HOW TO OPTIMIZE THREE MIRROR TELESCOPE USING THIS TECHNIQUE

Very difficult answer quickly.

I work from 20 y. in a Cassegrain radiotelescope, i think to have a little experience about.

1. For my opinion the distance between mirrors is choosed from mechanical considerations, maintenance comfort, and horn feasibility. As large is the main mirror as small F/D became practical.

Ray tracing tecnhique is widely used by cad like Grasp. Ray tracing is merely staight lines and don't take in account the beam deformations due to "lens effects".

Dr. Goldsmith of Millitech has wrote many papers about the deformations, the "waist" concept is widely by Goldsmith to describe waveguide beams and curved, multifocal mirrors.