What is the principle function of the shading ring?
The shading ring plays a role of shading, such as the shading ring of the mobile phone lens and the lens shading ring of the camera lens. It is a piece of Mylar sheet that is stamped with SOMA shading material and embedded in the lens. Because of the shading function, everyone calls it Shading ring, shading gasket.
Its principle is based on the principle of physical phenomena (small hole imaging), and the processing requirements are relatively strict. Therefore, the requirements for materials are also higher-level requirements. The Japanese SOMA shading material is basically used in the market. It is a double matte black PET.
The shading ring on the shading device can be large or small. Rotating the shading device can adjust the intensity of light. The large diaphragm transmits more light to make the field of view bright, and the small diaphragm transmits less light and darkens the field of view; rotate the collimator screw to adjust the lens barrel Lifting.
The main function of the shading ring
1: In the microscope structure, the adjustment of the lens barrel up and down is the coarse collimation screw, not the shutter, so this option does not meet the meaning of the question;
2: During the use of the microscope, the image can be made clearer by adjusting the fine focus screw, so this option does not meet the meaning of the question;
3: In the use of the microscope, the light can be reflected into the light hole by adjusting the reverse mirror. If the light is weak, use a concave mirror, when the light is strong, use a flat mirror, so this option does not meet the meaning of the question;
4: In the microscope structure, the light intensity can be adjusted by adjusting the aperture size of the shutter; when aiming the light, turn the shutter so that the larger aperture is aligned with the light hole. If the aperture is smaller, the field of view is dark. Therefore, this option meets the meaning of the question;