Introduction to the structure of each part of the optical microscope
◆Mechanical part
(1) Mirror base: It is the base of the microscope to support the entire mirror body.
(2) Mirror column: It is the upright part on the mirror base, which is used to connect the mirror base and the mirror arm.
(3) Mirror arm: one end is connected to the mirror column, and the other end is connected to the lens barrel, which is the hand-holding part when taking and placing the microscope.
(4) Lens barrel: connected to the upper front of the lens arm, the upper end of the lens barrel is equipped with an eyepiece, and the lower end is equipped with an objective lens converter.
(5) Objective lens converter (rotator): It is connected to the bottom of the prism shell and can rotate freely. There are 4-5 round holes on the disk, which are the parts for installing the objective lens. Turning the converter can change the objective lens of different multiples. Observation can only be carried out when there is a knocking sound. At this time, the optical axis of the objective lens is just aligned with the center of the light hole, and the optical path is connected.
(6) Mirror stage (stage): under the lens barrel, there are two shapes, square and round, for placing slide specimens. There is a light hole in the center. The stage of the microscope we use is equipped with a slide specimen pusher ( Pusher), there is a spring clip on the left side of the pusher, which is used to hold the slide specimen, and there is a pusher adjustment wheel under the stage, which can make the slide specimen move left and right, front and back.
(7) Regulator: It is a screw of two sizes installed on the mirror column. When adjusting, the mirror table moves up and down.
①Coarse adjuster (coarse screw): The large screw is called a coarse adjuster, which can make the mirror stage move up and down quickly and greatly, so it can quickly adjust the distance between the objective lens and the specimen to make the object appear in the field of view, usually in the When using a low magnification lens, first use the coarse adjuster to quickly find the object.
②Fine adjuster (fine spiral): The small spiral is called a fine adjuster, which can make the mirror stage rise and fall slowly when moving, and is mostly used when using a high-power mirror, so as to obtain a clearer object image, and to observe different layers and different depths of the specimen Structure.
(8) Converter: The objective lens of different multiples can be converted during use. After the objective lens is converted, the coarse adjuster is not allowed, only the fine adjuster can be used, so that the image is clear.
◆Illumination part
Installed under the mirror stage, including reflector and light collector.
(1) Reflective mirror: it is installed on the mirror base and can be rotated in any direction. It has two sides, flat and concave. Its function is to reflect the light from the light source to the condenser, and then illuminate the specimen through the light hole, and the concave mirror concentrates the light. The effect is strong, suitable for use when the light is weak, and the light concentrating effect of the flat mirror is weak, suitable for use when the light is strong.
(2) The light collector (light collector) is located on the light collector frame under the mirror stage, which is composed of a condenser lens and an aperture, and its function is to concentrate the light on the specimen to be observed.
① Condenser: It is composed of one or several lenses, which can gather light, strengthen the illumination of the specimen, and let the light enter the objective lens. There is an adjustment screw next to the mirror column. Turning it can lift the condenser to adjust the field of view. The strength of brightness.
②Aperture (iridescent aperture): Under the condenser, it is composed of more than a dozen metal sheets, and a handle protrudes from the outside of it. Pushing it can adjust the size of its opening to adjust the amount of light.
◆Optical part
(1) Eyepiece: Installed on the upper end of the lens barrel, there are usually 2-3 pieces, with 5×, 10× or 15× symbols engraved on it to indicate its magnification, and the 10× eyepiece is generally installed.
(2) Objective lens: Installed on the rotator at the lower end of the lens barrel, generally there are 3-4 objective lenses, the shortest one engraved with the symbol "10×" is a low-magnification lens, and the longer one is engraved with the symbol "40×" It is a high-power lens, and the longest one engraved with the "100×(oil)" symbol is an oil lens. In addition, there is often a circle of lines of different colors on the high-power lens and the oil lens to show the difference.
The magnification of the metallographic microscope is the product of the magnification of the objective lens and the magnification of the eyepiece. For example, if the objective lens is 10× and the eyepiece is 10×, the magnification is 10×10=100.
