Assertion: telescope's mirror | /r/HasProperty | flat
Facets:
value: in this design
type: OTHER
value: almost
type: DEGREE
Source sentences:
text: The fourth and fifth mirrors are (almost) flat, and provide adaptive optics correction for atmospheric distortions (mirror 4), and tip-tilt correction for image stabilisation (mirror 5).
text: In this design, the secondary mirror is flat and imparts no power as do those of the Mak-Cass and Schmidt-Cass telescopes.