-
Anonymous users2024-01-241.The common name of the door mirror is cat's eye. Why is it called a cat's eye? Because the light is refracted through it and looks like the light emitted by the Persian cat's eyes at night, it is nicknamed the cat's eye.
2. Function: Looking out through the door mirror from the door, you can see all the scenes within the range of about 120 degrees outside the door, but you can't see anything in the room through the door mirror from outside the door If you install this mirror on the door of a public house or private apartment, it can play a certain role in the anti-theft and security of the family.
3 principle: the door mirror is composed of two lenses When we look out from the door, the objective lens L1 is a concave lens, and the eyepiece L2 is a convex lens The focal length of the objective lens L1 is extremely short, and it will AB the person or thing outside the door into a very small upright virtual image A B, this image just falls in the first focus of the eyepiece L2, L2 plays the role of a magnifying glass, and finally obtains a more magnified upright virtual image, which is just near the bright vision distance of the human eye, and the situation outside the door can be seen clearly.
-
Anonymous users2024-01-23No,,, a cat's eye is made up of a convex lens and a concave lens,,, all cat's eyes are made up of two mirrors like this.
The convex lens outside the door, the concave lens inside the door, you can find a door to touch.
This is a combination lens.
Have you noticed that this cat's eye can only see clearly from the inside out, and you can't see things clearly from the outside to the inside? The reason for this is that this is a combination lens, a device that combines a convex lens and a concave lens. >>>More
The safety hazards of cat's eye are still relatively large, and now the high-end anti-theft doors on the market generally use explosion-proof pins.
Yes You can do it constantly, and you can have everything.
The security door at home is very important, it is an important guarantee of our home security. When buying an security door, some people will have questions:What is the difference between an security door with a peephole and an anti-theft door without a peephole? >>>More