Red objective lens of an optical microscope
The red objective lens of optical microscope means 4 times magnification, yellow means 10 times, blue means 40 times, and white means 100 times. The total magnification of the microscope is obtained by multiplying the multiple of the eyepiece by the multiple of the objective lens.
The "10" and "4" in the upper numbers of the optical microscope indicate that the magnification of the objective lens is 10 times or 4 times. The magnification here is not the magnification of the area, but the magnification of the length or width of the image, and the total magnification of the microscope is equal to the product of the magnification of the objective lens and the eyepiece, and the magnification of the objective lens is proportional to its length. The greater the magnification of the objective lens, the longer the objective lens.
Parameter Links for Optical Microscopy
The working distance of the objective lens of an optical microscope is related to the focal length of the objective lens. The longer the focal length of the objective lens, the lower the magnification, and the longer the working distance. Example: 10x objective lens is marked with 10/0.25 and 160/0.17, where 10 is the magnification of the objective lens. 0.25 is the numerical aperture; 160 is the lens barrel length (in mm); 0.17 is the standard thickness of the cover glass (in mm).
The effective working distance of the 10x objective lens is 6.5mm, and the effective working distance of the 40x objective lens is 0.48mm. The role of the objective lens is to magnify the specimen for the first time, and it is the most important component that determines the performance of the microscope.
When the objective lens has clearly resolved the fine structure, if it is not re-magnified by the eyepiece and cannot reach the size that the human eye can distinguish, then it will not be seen clearly; but the fine structure that the objective lens cannot distinguish can still be seen clearly even though it is re-magnified by the high-power eyepiece, so the eyepiece can only be used for magnification, and will not improve the resolution of the microscope.
