Advanced Coma-Free Optical System - Meade LX850 Instruction Manual

APPENDIX E:

ADVANCED COMA-FREE OPTICAL SYSTEM

(2)
(1)
Focal
Plane
Unlike Schmidt-Cassegrain
Advanced Coma-Free (ACF) optical system provides
razor-sharp pin-point star images all the way to the very
optical system brings the highest level of performance
to the amateur astronomer.
In the ACF design shown above, light enters from the
right, passes through a thin lens with 2-sided aspheric
correction ("correcting plate"), proceeds to a spherical
primary mirror, and then to a hyperbolic secondary
mirror. The hyperbolic secondary mirror multiplies the
effective focal length of the primary mirror and results
in a focus at the focal plane, with light passing through
a central perforation in the primary mirror.
(1)
Ray (1)
Primary Baffle Tube
Field Stops
Primary Mirror
systems, Meade's The Meade ACF optical system includes an oversized
this phenomenon which results in Meade ACF having
for-aperture, than other systems utilizing standard-size
primary mirrors. Field stops machined into the inside-
(2)
(1)
(2)
Ray (2)
Secondary
Mirror
Correcting
Plate
Secondary
Baffle
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