Lens Introduction And Application Analysis

Brief introduction to lens concept

A lens is an optical element made of a transparent material whose surface is part of a spherical surface. The lens is composed of several lenses, including plastic and glass. Glass lenses are more expensive than plastic. Generally, the lens structures used for cameras are: 1P, 2P, 1G1P, 1G2P, 2G2P, 4G, etc. The more lenses, the higher the cost. Therefore, a high-quality camera should use a glass lens, and its imaging effect is better than a plastic lens. It plays an important role in astronomy, military, transportation, medicine, art and other fields.

Lens classification

Convex lens

A convex lens is a lens with a thicker center and thinner edges. Convex lens has the function of condensing light, so it is also called "converging lens" and "positive lens" (which can be used for hyperopia and reading glasses). Such lenses can be divided into:

a. Bi-Convex Len-is a two-sided convex lens;

b. Plano-convex lens-a lens with a convex side and a flat side;

c. Concave-convex lens-a lens with one convex side and concave side.

concave lens

Concave lens is also called negative spherical lens. The center of the lens is thin, the periphery is thick, and it is concave, so it is also called concave lens. The image formed by the concave lens is always smaller than the upright virtual image of the object. The concave lens is mainly used to correct myopia. Concave lens has the function of diverging light, so it is also called divergent lens and negative lens (which can be used for myopia glasses). Such lenses can be divided into:

a. Biconcave lens-is a lens with concave on both sides

b. Plano-Concave Lens-a lens with a concave side and a flat side

c. Convex-concave lens-a lens with one convex and one concave

Plano-Concave Lens

Lens function 

1; Because the lens has a strong light-gathering ability, it is used to illuminate the road, not only the road is bright, but also clear.

2; Since the light dispersion is very small, its light range is far and clearer than ordinary halogen lamps. Therefore, you can see far away things in the first time, avoid crossing the intersection or miss the target.

3; Compared with the headlights with traditional lamp holders, the headlights with lens-type lamp caps have uniform brightness and strong penetrating power, so they have stronger penetrating power no matter in rainy or foggy weather. In this way, oncoming vehicles can receive light information as soon as possible and avoid accidents.

4; The lifespan of the HID bulb in the lens is 8 to 10 times that of ordinary bulbs, so as to reduce the unnecessary trouble of changing the lamp.

The difference between lenses

Different structure

The convex lens is composed of a transparent lens body ground into a spherical surface on both sides, thin on both sides and thick in the middle

The concave lens is composed of a transparent lens body that is ground into a concave spherical surface on both sides, thick on both sides and thin in the middle

Different effects on light

The convex lens mainly converges the light, but it also diverges when the object distance is less than the focal length.

The concave lens mainly diverges the light

Different imaging properties

Convex lens is refractive image

The concave lens is after the light passes through the concave lens, it becomes an erect virtual image, while the convex lens becomes an inverted real image. The real image can appear on the screen, but the virtual image cannot.