Newtonian-Cassegrain telescope [nü`tō·nē·ǝn `kas´gran `tel·ǝ´skōp] OPTICS A modification of a Cassegrain telescope in which the light reflected from the hyperboloidal secondary mirror is again reflected from a diagonal plane mirror and focused at a point on the side of the telescope, avoiding the need to pierce the primary mirror and making the eyepiece more accessible. Also known as Cassegrain- Newtonian telescope. |