Assertion: eyepiece's field lens | /r/HasProperty | placed sufficient distance
Facets:
value: to ensure
type: PURPOSE
value: in all modern eyepiece designs
type: OTHER
Source sentences:
text: In all modern eyepiece designs, the field lens is placed a sufficient distance away from the intermediate image plane to ensure that dust or other surface debris and defects on the lens surface are not visualized along with the specimen.