Question

What are the unit planes?

Answer 1

unit planes in optical system including a plane-parallel plate.

Answer 2

Explanation:

2 the unit planes H1 and H1′ are those of the lens V1V2 which becomes a plane-parallel plate as R1=R2 increases to infinity. H2 and H2′ are the unit planes of another optical system of a finite f2. H and H′ are the unit planes of the compound system.

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