Use the magnifying glass to make it close to the eyes and put things within its focus to become a positive image.The role of magnifying glass is to magnify the perspective.Some elderly people use magnifying glass, so what is the role of magnifying glass?What is the principle of magnifying glass?What are the uses of magnifying glass?Lets take a look with Xiaobian.
The role of a magnifying glass
1. The image of magnifying objects -the most important feature of magnifying glass
Putting the magnifying glass in front of the object can watch the enlarged image from the lens, notice that the object is actually not enlarged.
2. Focus on the fire -secondary function
Under strong light, the focus of the lens will be particularly light, and the focus part will be zoomed or ignited.
Principles of magnifying glass
1. In order to see the details of the tiny objects or objects, you need to move the object close to your eyes. This can increase the perspective and form a large image on the retina.But when the object is too close to the eye is too close, it cannot be seen clearly.In other words, you must inspect the autumn, not only to make the object have a large corner of the eyes, but also take the right distance.Obviously for the eyes, these two requirements are restricted by each other. If a convex lens is configured in front of the eyes, this problem can be solved.The convex lens is the simplest magnifying glass, which is a simple optical instrument that helps the eyes to observe small objects or details.
2. Taking convex lens as an example, calculate its amplification skills.Put the object PQ between the focus of the lens L and the lens and get it close to the focus, as shown in Figure 2-20 (a), so the object is an enlarged virtual p -Q ′ through the lens.If the square focal length of the convex lens is 10cm, the amplifier of the magnifying glass made of the lens is 2.5 times, and it is written as 2.5 ×.If you consider only the amplification skills, the focal length should be shorter, and it seems that this can get the ability to make any Antimony.However, due to the existence of the aberration, the zoom -in -the -base contract is generally adopted by 3 ×.If a duplex amplifier (such as a eyepiece) is adopted, the aberration can be reduced and the amplifier can reach 20 ×.
Break the use of mirror
1. The inspection, processing, installation and repair of various operations in the electronic industry;
2. Observation of facial skin and pores in the beauty industry, repair armor, ears, etc.;
3. Sculpture and appreciation of artworks;
4. Check and repair of cameras, clocks, etc.
5. Usually people use it when reading, especially suitable for the reading of the elderly and students under the dim light;
6, dentist, tailor, embroidery, etc.;
7. Finance, finance and taxation, philatelic, jewelry, printing, agriculture and other product characteristics.