Not only glass, any other transparent material that is shaped appropriately can converge or diverge parallel rays from a point. A transparent material such as glass in that shape is called a lens. The piece of material is carefully molded or ground so that it reflects light rays. These reflected rays form an image. You can see a lens as a series of refracting prisms. Each tiny prism produces its own image by refracting light. All these tiny prisms work together to create a bright image.
Types of Lenses
There are the double concave lens, double convex lenses, and many other types of lenses used for different applications. Different materials are used for making a double concave lensand other types of lenses in different shapes. Some lenses are symmetrical across their principal axis/horizontal axis.
In this article, we will cover two categories of lenses including diverging lenses and converging lenses.
This type of lens covers parallelly traveling light rays to its horizontal axis/principal axis. The lower and upper edges of a converging lens are thin. The middle of the lens is thick.
This type of lens diverges parallelly traveling light rays to its horizontal axis/principal axis. The lower and upper edges of a diverging lens are thick. The middle of the lens is thin. You can easily identify both types of lenses simply with their appearance.
Double Convex Lens
A lens of this type is symmetrical across both the vertical and horizontal axis. The lens has two faces. Originally, each face of the lens is thought to be a part of a sphere. As the middle of a double convex lens is thicker, it indicates that parallelly traveling light rays are converged to its horizontal axis/principal axis. It is a converging lens.
Double Concave Lens
Both double concave lens and double convex lens are symmetrical across their vertical axis and horizontal axis. A double concave lens has two faces and both faces are originally thought to be a part of a sphere. As the middle of the lens is thinner, this indicates that the lens diverges parallelly traveling light rays to its horizontal axis/principal axis. It is a diverging lens.
Language of Lenses
Now you know that a lens refracts light rays to create an image. Whether you are buying a double concave lens, the double convex lens, or any other type of lens for a school lab, college lab, medical facility, or R&D facility, you need to be aware of some terms. If you are not familiar with these terms, you need to spend some time to review them to make the right purchase. These terms are also important to understand how a lens works.
A symmetrical lens is a slice of a sphere. This sphere has a line passing through it. This line is called the principal axis. A vertical axis is a lens that bisects this lens into two halves. Focal point is another important term associated with lenses. A converging lens converges light rays to a focal point. The light rays diverged by a diverging lens intersect at a point called the focal point. If you see diagrams in physics books, the letter ‘F’ is used for a focal point. Each side of a lens has a focal point. Mirrors reflect light. On the other hand, a lens reflects light rays. The focal length is the distance between the focal point and the mirror. The letter ‘f’ is used for focal length.
Lenses are used in school labs, college labs, clinics, research and development facilities, and many industries for different applications. You must be familiar with different types of lenses and the terms associated with them.