Handbook of Biomedical Optics

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25.1 Introduction to Confocal Imaging

A confocal imaging system creates a high-contrast image of a

single plane within an optically transparent or translucent mate-

rial by blocking most of the out-of-focus light that degrades the

quality of the image with conventional microscopy techniques.

Reducing out-of-focus light provides the ability to image indi-

vidual planes (optical sections) within the sample without hav-

ing to disturb the natural morphology by freezing and cutting the

sample into thin slices, as is the current procedure for histology. A

confocal microscope uses a point source of light, such as a focused

laser beam, to illum ...