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9. Auxiliary Optics for Telescopes
example, we choose p = 0.2, then m =
1.7762,
K^ = -1.4912, K2 = -26.905,
and k = 0.4338. From these results we see that the mirrors, especially the
secondary, are strongly hyperbolic and that the obscuration of the secondary is
larger than that of the typical RC telescope.
The next step in the design is simply one of substituting m, j?, and a choice of
g into Eq. (9.3.3) and finding a first-order solution for
b.
The telescope parameters
and the values of
b
and g are then the starting point for computer optimization of
the complete system, telescope plus corrector plate.
9.4. CASSEGRAIN FOCAL REDUCERS