
The design of optical instruments is renowned for requiring very high
precision calculations. The directory will hold a program that
experiments with the design of a catadioptric telescope using the high
precision library in cintcode/g/arith.h and arith.b.

The telescope has a convex lens objective with front and rear
spherical surfaces of radius R1 and R2. The thickness is of the
objective lens is held in T1.  A rear silvered concave glass mirror
whose front and rear surfaces have radii R3 and R4 is placed a roughly
half the focal length of the objective. The thickness of the mirror is
held in T2. The objective lens is of crown glass with refractive index
of between 1.50 and 1.54, and the concave mirror is made of flint
glass with refractive index of between 1.60 and 1.62. We assume the
refractive index of these two glasses for blue and red light is as
follow.

               crown        flint
blue 486 nm    1.51690      1.6321
red  640 nm    1.50917      1.6161

The program performs ray tracing thought the telescope for blue and
red at various small angle relative to the axis of the telescope.
These rays enters the objective at various positions. the result
is an image of the positionf these rays hit thr focus plane. With
perfect optics they would all hit the focus plane at the same point.

MR
16 Apr 2016
