Fincham\'s test differentiates cataract from –
The coloured halos in primary angle closure glaucoma must be differentiated from those found in acute purulent conjunctivitis and early cataractous changes :-


In conjunctivitis, the halos can be eliminated by irrigating the discharge.
The halos of glaucoma and immature cataract may be differentiated by Fincham's test in which a stenopaeic slit is passed across the pupil. During this test glaucomatous halo remains intact, while a halo due to cataract is broken up into segments.
Conjunctivitis
Iridocyclitis
Open angle Glaucoma
Ac. Congestive Glaucoma