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
G02B5/08
Mirrors
G02B5/08
Mirrors
G02B5/0883
with a refractive index gradient
G02B5/0883
with a refractive index gradient