Principle and maintenance of optical microscope
The magnification of the specimen is mainly done by the objective lens, the greater the magnification of the objective lens, the shorter its focal length. The smaller the focal length, the smaller the distance between the lens of the objective lens and the slide. The working distance of the oil mirror is very short, and extra attention is needed when using it. The eyepiece only acts as a magnifier and does not improve resolution; the standard eyepiece has a magnification of ten times. The spotting scope enables light to enter the objective lens after irradiating the specimen, forming a large-angle conical column of light, and thus is important for improving the resolution of the objective lens. The condenser lens can be moved up and down to adjust the brightness of the light and the variable diaphragm can adjust the size of the incident beam.
Microscope light source, natural light and light can be, to light is better, because the light colour and intensity are easy to control. General microscope available ordinary light, high quality microscope to use the microscope lamp, in order to give full play to its performance. Some need very strong illumination, such as dark field illumination, photography, etc., often use halogen lamps as a light source. Optical microscope is composed of two parts: optical magnification system and mechanical device.
Principle:
The magnification efficiency of the microscope is determined by the length of the light wave used and the numerical aperture of the objective lens, shorten the wavelength of the light wave used or increase the numerical aperture can improve the resolution, the amplitude of the light wave of the visible light is narrower, and the wavelength of the UV light is shorter can improve the resolution, but it can not be used to observe directly with the naked eye. So the use of reduced light wavelength to improve the resolution of the optical microscope is limited, increase the numerical aperture is the ideal measure to improve the resolution. The total magnification of the microscope is the product of the magnification of the eyepiece and objective lens, and the higher the magnification of the objective lens, the higher the resolution.
