Optical lens manufacturer - How to identify the type of lens!
Lens is an optical element made of transparent glass, crystal and other materials. It is a refractor, and its refracting surface is a transparent body with two spheres, or one sphere and one plane. Generally, lenses can be divided into two categories: convex lens and concave lens. The central part thicker than the edge part is called convex lens, which has three kinds of biconvex, flat convex and concave convex; the central part thinner than the edge part is called concave lens, which has three kinds of biconvex, flat concave and convex concave.
Optical lens manufacturer - In order to distinguish a convex lens from a concave lens, we usually use the method of "touching the thickness of the lens by hand, looking at the image by the eye, and light over focusing and scattering"
Optical lens manufacturer - 1. Feel the thickness by hand.
This is based on the shape characteristics of the two kinds of lenses and distinguished by comparing the thickness of the center and edge of the lens. The lens with thick middle and thin edge is convex, and the lens with thin middle and thick edge is concave;
Optical lens manufacturer - 2. Visual signs.
This is distinguished from the different imaging features of the lens.
(1) When a lens is used to observe a nearby object, a convex lens forms an upright and enlarged image, and a concave lens forms an upright and reduced image.
(2) The inverted image is convex lens, while the upright image is concave lens;
Optical lens manufacturer - 3. Light gathers and disperses.
This is from the lens of light convergence or divergence to start to identify. Put a piece of white paper under the lens and adjust the distance between the lens and the white paper. If you can find the smallest and brightest light spot (focus) on the paper, it is a convex lens, and you can see a concave lens on the paper to enlarge the aperture.
