Quick Review Cards for Medical Laboratory Science

Other Types of Microscopy Laboratory Operations Review 39

EXPLANATION APPLICATION IN CLINICAL LABORATORY

Light Microscopes
Darkfield

Fluorescent

Interference contrast

Phase contrast

Polarizing

Identification of live Treponema pallidum&

other microorganisms

Direct & indirect fluorescent antibody

stains in microbiology & immunology

Wet mounts

Manual platelet counts, urine sediments

(good for hyaline casts)

Identification of crystals in urine & synovial

fluid. Confirmation of fat or oval fat bodies

in urine sediment.

Brightfield microscope with special condenser. Objects appear

white against black background.

Brightfield microscope with 2 special filters. Fluorescent

dyes absorb light of 1 wavelength & emit light of longer

wavelength. Objects appear green, yellow, or orange against

black background.

Brightfield microscope with special slit aperture below con-

denser, polarizer, & special amplitude filter (modulator) in back

of each objective. Gives 3-D effect to unstained specimens.

Brightfield microscope with phase condenser & phase objec-

tives. Subtle differences in refractive index converted to

clear-cut variations of light intensity & contrast. Good for

living cells, unstained specimens.

Brightfield microscope with 2 crossing filters—polarizing

filter below condenser, analyzer between objective & eye-

piece. Objects that can refract light (birefringent) appear

white against black background.

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