Assertion: reflecting telescope's mirror | /r/HasProperty | reflector
Facets:
Source sentences:
text: Telescopes of a given aperture that use lenses (refractors) are typically more expensive than those using mirrors (reflectors) because both sides of a lens must be polished to great accuracy.
text: Before flocking, you will need to remove all optical components, such as the objective lens (refractors), primary and secondary mirror (reflectors), eyepieces, focuser, finder, etc.