phase microscope

WordReference Random House Unabridged Dictionary of American English © 2026

phase′ mi′croscope, 

a microscope that utilizes the phase differences of light rays transmitted by different portions of an object to create an image in which the details of the object are distinct despite their near-uniformity of refractive index. Also called phase′-con′trast mi′croscope  (fāz′kon′trast). 
• 1945–50