Phase Contrast Microscopy
(Optical Components, Working Principle and Applications of Phase Contrast Microscope)
Working Principle of an Ordinary Microscope:
In an ordinary microscope, the object is viewed due to differences in colour intensities of the specimen. To create the colour intensities, the specimen is first stained with suitable dyes which will impart specific colour. In an ordinary microscope, the contrast is obtained when the light rays pass through a stained specimen because different stains absorb different amounts of light. These differential absorption properties of stained specimen modify the intensity or amplitude of the light waves transmitted by different regions of the cells and this ultimately creates contrast in the image. Thus, staining is essential to create contrast in an ordinary microscope. Moreover, the unstained specimen cannot be observed through an ordinary microscope.
Why Phase Contrast Microscope?
The Phase Contrast Microscope is used to visualize unstained living cells. Most of the stains or staining procedures will kill the cells. Phase contrast microscopy enables the visualization of living cells and life events.