Principles of confocal microscopy and the field
1, confocal microscope in the reflected light on the optical path plus a half-reflective half-lens, will have passed through the lens of the reflected light folded in the other direction, in the focus of a baffle with a pinhole, the hole is located in the focal point, the baffle is a photomultiplier tube behind. It can be imagined that the reflected light before and after the focal point of the detector light through this set of confocal system, will not be able to focus on the small hole, will be blocked by the baffle. So the photometer measures the intensity of the reflected light at the focal point.
2, principle: the traditional optical microscope uses a field light source, the image of each point on the specimen will be interfered by the diffraction or scattering of light from the neighbouring points; laser scanning confocal microscope uses a laser beam through the illuminating pinhole to form a point source of light on the specimen in the focal plane of the scanning of each point on the specimen, the specimen is irradiated, in the detection of the pinhole at the imaging, by the detection of the pinhole after the photomultiplier tube (PMT) or the cold electrocoupling device (cCCD) point by point or point by point or point by point, the light intensity is measured by a photometer. cCCD) receives point by point or line by line, and rapidly forms a fluorescent image on the computer monitor screen. The illumination pinhole and detection pinhole are conjugate with respect to the focal plane of the objective lens, the point on the focal plane is focused on the illumination pinhole and the emission pinhole at the same time, and the point outside the focal plane will not be imaged at the detection pinhole, so that the confocal image is an optical cross-section of the specimen, which overcomes the drawbacks of the fuzzy image of the ordinary microscope.
3,Application fields: medicine, animal and plant research, biochemistry, bacteriology, cell biology, tissue embryo, food science, genetics, pharmacology, physiology, optics, pathology, botany, neuroscience, marine biology, materials science, electronic science, mechanics, petroleum geology, mineralogy.
