Mechanical components and description of the microscope
The mechanical parts of a microscope include the mirror holder, barrel, objective lens converter, stage, pusher, coarse adjustment handwheel, fine adjustment handwheel, and other components.
1) Mirror holder: The mirror holder is the basic support of a microscope, consisting of a base and a mirror arm. It is connected to a stage and a tube, and serves as the foundation for installing optical amplification system components. The base and mirror arm serve to stabilize and support the entire microscope.
2) Tube: The tube is connected to the eyepiece and the transducer, forming a darkroom between the eyepiece and the objective lens (installed under the transducer). The distance from the rear edge of the objective lens to the end of the barrel is called the mechanical barrel length. Because the magnification of the objective lens is dependent on a certain length of the lens barrel. The change in the length of the lens barrel not only affects the magnification, but also affects the imaging quality. Therefore, when using a microscope, the length of the lens barrel cannot be arbitrarily changed. Internationally, the standard cylinder length for microscopes is set at 160mm, which is usually marked on the outer shell of the objective lens. There are two types of tube barrels: single tube and double tube. Single tube tube barrels are divided into upright and inclined types, while double tube tube barrels are all inclined types.
3) Objective lens converter: Three to four objective lenses can be installed on the objective lens converter, usually three objective lenses (low magnification, high magnification, and oil lens). By rotating the converter, one of the lenses can be aligned with the lens barrel as needed (note that the conversion lens cannot be rotated while holding the objective lens), forming a magnifying system with the eyepiece lens.
4) Stage: There is a hole in the center of the stage that serves as a light channel. There are spring specimen clamps and pushers installed on the stage, which are used to fix and move the position of the specimen, so that the microscopic object is located exactly at the center of the field of view.
5) Pusher: It is a mechanical device for moving specimens. It is composed of a metal frame with two pushing gear axes, one horizontal and one vertical. A good microscope has a scale engraved on the vertical and horizontal frame rods, forming a very precise plane coordinate system. If we need to observe a certain part repeatedly, we can record the values of the vertical and horizontal scales, and move to the same value in the future to find it.
6) Coarse adjustment handwheel (coarse spiral): The coarse adjustment handwheel is a mechanism that quickly moves and adjusts the distance between the objective lens and the specimen.
7) Fine tuning handwheel (fine spiral): Using a coarse tuning handwheel can only roughly adjust the focal length. To obtain the clearest object image, it is necessary to use a macro spiral for fine tuning.
