How to calculate the magnification of microscope?
1. Optical magnification. It refers to the magnification of the object we observe from the microscope eyepiece. The calculation method of optical magnification is relatively simple, that is, objective lens multiple * eyepiece multiple. For example: the calculation of the magnification of a stereo microscope, the objective lens of a continuous zoom stereo microscope is usually 0.7-4.5 times, then in the case of 10 times the eyepiece, the total magnification of this microscope is 7-45 times; biological microscope, The calculation of the metallographic microscope is simpler. The general objective lens configuration is 4 times, 10 times, 40 times, 100 times, the conventional eyepiece configuration is 10 times, and there are 16 times, 20 times, etc., as long as the eyepiece and objective lens The multiples are multiplied separately to obtain the total magnification.
2. Digital magnification. Digital magnification refers to the magnification of the image displayed on the image after the external device is connected. At present, there are more trinocular microscopes on the market, which are connected to a computer, monitor or TV through a CCD device for imaging observation, so as to reduce eye fatigue. It is also easy to share with others.
(1) Measure the image directly. Put the micrometer under the microscope, then take a ruler to directly measure the length of the micrometer on the display, and compare the measurement result of one grid on the display/the actual length of each grid of the micrometer (usually it will be directly marked on the micrometer has the length of each grid) = the multiple by which the object is enlarged. The multiple of the object being magnified / the multiple of the current objective lens = digital magnification. Usually, a scale is added to the image to indicate the magnification of the object. Note: If there is no micrometer, you can use a ruler instead, and you can measure a few more grids during calculation to reduce errors.
(2) Calculate the actual magnification through the formula. Digital magnification = objective lens magnification * {25.4 * screen size (inch) / CCD diagonal length} * adapter magnification, if the system magnification, it needs to be multiplied by the system magnification.
1: The multiple of the objective lens refers to the multiple of the objective lens of the microscope you are using now, such as 20 times;
2: The magnification of the adapter: refers to the magnification of the connecting part of the microscope and the imaging device, usually 1 times, but also 0.35, 0.5, 0.63 times;
3: 25.4*screen size (inches): Here is the calculation of converting the screen size into millimeters, 1 inch=25.4mm;
4: The length of the CCD diagonal: refers to the chip size of the CCD, often 1/3 inch, 1/2 inch, 2/3 inch, the corresponding lengths are 6mm; 8mm; 11mm, this is the industry internally unified.
