PHASE CONTRAST PHASE CONTRAST

MICROSCOPYMICROSCOPY

Phase contrast microscope is a Phase contrast microscope is a technique which makes highly technique which makes highly transparent objects more visible transparent objects more visible without killing them.without killing them.

Invented by the Dutch physicist Invented by the Dutch physicist Frederick Frederick

Zernike in 1930Zernike in 1930

PRINCIPLEPRINCIPLE

It converts the different degrees It converts the different degrees of retardation of light rays of retardation of light rays passing through a translucent passing through a translucent material into amplitude material into amplitude differences to create an image differences to create an image with increased contrast.with increased contrast.

COMPONENTSCOMPONENTS

Light sourceLight sourceAnnular diaphragmAnnular diaphragmCondenser lensCondenser lensSpecimen stageSpecimen stageObjective lensObjective lensPhase platePhase plateTelescopic lensTelescopic lensEye pieceEye piece

Cheek cellCheek cell

Clostridiumbotulinum, the bacterium responsible for botulism, with

subterminaloval endospores;

Spirillum volutans, a very large bacterium with

flagellar bundles

Parameciumstained to show a large central macronucleus with a

small sphericalmicronucleus at its side

APPLICATIONSAPPLICATIONS Objects with poor intensity can be resolved well.Objects with poor intensity can be resolved well.

Image of the unstained object can be obtainedImage of the unstained object can be obtained

It is widely used in microbiology and tissue It is widely used in microbiology and tissue culture research to detect bacteria, cellular culture research to detect bacteria, cellular organelles and other small entities in living organelles and other small entities in living specimensspecimens

It allows the visualization of living unstained cells It allows the visualization of living unstained cells and their organelles.and their organelles.

For the detection of bacterial components such For the detection of bacterial components such as endospores and inclusion bodies containing as endospores and inclusion bodies containing poly β hydroxy butyrate, polymetaphosphate, poly β hydroxy butyrate, polymetaphosphate, sulpher and other substances sulpher and other substances