A catadioptric telescope that uses a thick spherical corrector lens and a spherical primary mirror incorporated in an all-spherical design to capture light and produce an image. The lens is deeply-dished so that it corrects for the spherical aberration of the mirror. Advantages of the design include little need for collimation.
Typically they have a high focal ratio and a small secondary obstruction that result in high contrast and resolution when compared with than other catadioptric designs or the reflecting telescopes the use only mirrors.
Referred to as a Mak.