Assertion: telescope's mirror | /r/AtLocation | optical axis
Facets:
Source sentences:
text: A Schmidt-Cassegrain telescope (SCT) in its usual configuration consists of a short tube with a concave spherical primary mirror, a full-aperture corrector lens, and a smaller convex secondary mirror located on the optical axis near the center of the corrector plate.
text: In its classical configuration, a Schmidt-Cassegrain consists of a short tube with a spherical concave primary mirror, a full-aperture corrector lens, and a smaller convex secondary mirror located on the optical axis near the center of the corrector plate.