1, used for observing paper and printing outlets of banknotes, tickets, postal services, coins and cards in finance, taxation, philatelic and electronic industries. Can accurately and quickly identify counterfeit banknotes, with high resolution, but violet light detection is not accurate, so use this instrument.

2. Used in jewelry industry, we can observe the internal structure and cross-section molecular arrangement of gems, and also analyze and identify ore specimens and cultural relics.

3. Used in printing industry, it can be used for fine correction, color correction, dot and edge extension observation, and can accurately measure screen mesh, dot size, overprint error and so on.

4. It can be used to observe and analyze fabric fiber and warp and weft density in textile industry.

5. Used in electronic industry, we can observe the traces, stripes and quality of copper and platinum plates on printed circuit boards.

6, used in agriculture, forestry, food and other departments to observe and study germs and insects.

7. It can also be used for animal and plant specimens, identification and analysis of evidence by public security departments, and scientific experimental research.

Second, a magnifying glass has two functions:

1, achromatic lens, can clearly observe the picture, identify gems, with a packaging box, light and easy to carry.

2. It can also be used for jewelry identification and detection, substrate surface quality and color correction, etc.

Extended data:

First of all, the magnifying glass principle

In order to see the tiny object or the details of the object clearly, it is necessary to move the object closer to the eye, which can increase the viewing angle and form a larger real image on the retina. But when the object is too close to the eye, it is not clear. In other words, to be good at observation, we should not only make the object have a large enough opening angle to the eyes, but also take a suitable distance.

Obviously, for the eyes, these two requirements are mutually restrictive. If you put a convex lens in front of your eyes, this problem can be solved. The convex lens is the simplest magnifying glass and a simple optical instrument to help the eyes observe tiny objects or details.

Second, the method of use

Observation method 1: make the magnifying glass close to the observed object, keep the observed object motionless and the distance between the human eye and the observed object unchanged, and then move the hand-held magnifying glass back and forth between the object and the human eye until the image is large and clear.

Observation method 2: the magnifying glass is as close to the eyes as possible. Keep the magnifying glass still and move the object until the image becomes bigger and clearer.

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