Assertion: telescope's tube | /r/CapableOf | focus light
Facets:
value: back along the optical axis
type: OTHER
value: to a secondary mirror
type: TRANSITIVE-OBJECT
Source sentences:
text: A telescope designed with a spherical or parabolic primary mirror at one end of the tube that reflects and focuses light back along the optical axis to a secondary mirror, which, in turn, redirects the light at a right angle to the optical axis and into an eyepiece.