Laser confocal microscopy uses laser light as the light source
The traditional optical microscope uses a field light source, and the image of each point on the specimen will be interfered by the diffraction or scattered light of adjacent points; the laser confocal microscope uses the laser beam to form a point light source through the illumination pinhole to scan each point of the focal plane of the specimen, and the irradiated point on the specimen is imaged at the detection pinhole, which is received point by point or line by point or line by the point multiplier tube (PMT) or cold coupled device (cCCD) behind the detection pinhole, and quickly forms a fluorescent image on the computer monitor screen. The illuminating pinhole and detecting pinhole are conjugate with respect to the focal plane of the objective lens. Points on the focal plane focus on the illuminating pinhole and emitting pinhole at the same time. Points outside the focal plane will not be imaged at the detecting pinhole. The confocal image obtained in this way is the optical cross section of the specimen, which overcomes the shortcomings of ordinary microscope image blur.
Laser confocal microscope is a set of observation, analysis and output system that uses laser as light source, adopts conjugate focusing principle and device on the basis of traditional optical microscope, and uses computer to process digital image of the observed object. The resolution of optical imaging is increased by 30%~40%, and ultraviolet or visible light is used to excite fluorescent probes to obtain fluorescent images of fine structures inside cells or tissues, and to observe physiological signals and changes in cell morphology at the subcellular level, becoming a new generation of research tools in the fields of morphology, molecular biology, neuroscience, pharmacology, genetics, etc.
