G
PHYSICS
G
PHYSICS
G02
OPTICS
G02
OPTICS
G02B
OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
G02B
OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
G02B5/00
Optical elements other than lenses
G02B5/00
Optical elements other than lenses
G02B5/20
Filters
G02B5/20
Filters
G02B5/28
Interference filters
G02B5/28
Interference filters
G02B5/284
of etalon type comprising a resonant cavity other than a thin solid film, e.g. gas, air, solid plates
G02B5/284
of etalon type comprising a resonant cavity other than a thin solid film, e.g. gas, air, solid plates