Lenses have been popular for ages for their multipurpose usages. They are applied for penetrating through minute objects to focus on the sun's rays. Moreover, Convex lenses have been a focal point and have been fascinating to everyone. Typically made of transparent plastic or glass, they have a minimum of one surface that curves outwards.
So, keep reading to learn about some convex lens uses.
Convex Lens Definition
Two spherical surfaces form an optical lens. When at least one of these surfaces or both the surfaces are bent outwards, they are called convex or biconvex lenses. The form of the convex lens is such that it is thinner at the edges and thicker at the centre.
The unique feature these lenses have is that the beam of light from outside is converged and focused on one point on the other side of the convex lens. Therefore it is also called a converging lens. A plano-convex lens has one flat surface and another convex surface.
Types Of Convex Lens
The convex lens can be segregated into three types depending upon their surface. The details about the three types of convex lens are mentioned below:
1. Plano Convex Lens
When the lens has one plain side and the other side is curved outwards, it is called the plano- convex lens. The positive focal length of the convex lens elements has a flat surface and a spherical surface. The design of the plano-convex lens is such that it can be used in non-critical applications. It can converge infinite parallel light and are typically used for multi-purpose focusing elements.
2. Double Convex Lens
The double convex lens has outward curves on both sides of the lens. Therefore they are often referred to as the biconvex lens. The focal length of these lenses is shorter than that of a plano- convex lens but has an equal surface radius and diameter.
The double convex lens is typically used in optical devices since it requires preferably longer focal lengths. They are also used in cameras, telescopes, monoculars, projectors and other such devices. The unique feature of these lenses is that it creates original images for photography and virtual images to be seen by the human eye.
3. Concave-Convex Lens
This lens type is unique as it curves outward from one side and inward from the other side. These lenses are used for balancing purposes where other lenses cause spherical aberrations. The laser beam is also controlled through the concave-convex lens. The concave-convex lens can be termed as a combination of the concave lens and convex lens.
Uses Of Convex Lens
A convex lens is popularly used in everyday routine and industrial purposes, experiments, laboratories and other commercial and household purposes. Some of the major convex lens uses can be summarized as under:
1. The most common and popular convex lens use is for human eyes lenses or optical uses. These lenses are designed to provide better visibility to human eyes.
2. The magnifying glass is also made out of a convex lens. With the use of magnifying glass, the object's distance seems to be shorter than the original focal length of the lens. The magnifying glass creates an erect and magnified image of the object towards the same side where the object is placed.
3. The long-sightedness or hypermetropia is treated effectively with the use of the convex lens.
4. The convex lens is known for creating crisp and clear images and focus lights. Therefore they are put to use in-camera also.
5. Several magnifying instruments such as camera lenses, telescopes, microscopes and other such instruments use compound lenses.
There are a number of such uses of convex lenses. The convex lenses focus light on the image, yet the quality of the image may not be at a standard. In such cases, it is advisable to use a combination of both lenses.
Functions Of Convex Lenses
The convex lens is often used in industrial purposes and high-end experiments. It has, therefore, a set of functions to be followed. Some of the major functions of the convex lens are mentioned below:
1. The convex lens forms a focused image of the object at infinity, which is real inverted.
2. The image is formed between an imaginary point and a focal point through a convex lens when the object is placed beyond an imaginary point. The image is diminished, inverted and real.
3. If the object is placed at the imaginary point, then the image formed at the imaginary point is of the same size, inverted and real.
4. When the object is placed between an imaginary point and a focal point, the image formed beyond the imaginary point is magnified, inverted and real.
5. If the object is placed at the focal point, then the image formed is magnified, inverted, and real and is at infinity.
6. If the object is placed between the centre of curvature and the focal point, then the image is formed beyond the imaginary point behind the object. This image is magnified and virtual.
Difference Between Concave Lens And Convex Lens
The concave lens is another kind of lens and is different from the convex lens. A straight beam of light is diverged by a concave lens, whereas a steam beam of light is converged by the convex lens. The convex lenses are thicker in form and thinner at the edges. But the concave lens is thinner in the middle and gets thicker towards the edges.
Final Words
A convex lens is rightly called a converging lens, as the refracted rays converge at a single point when the parallel rays pass through the convex lens. This is called the principal focal point. The distance between the object and the lens decides the angle through which light rays would enter the convex lens. The images formed by the convex lens are usually real.
However, the images may be real, imaginary, magnified, virtual, inverted or of the same size depending upon the object's placement. The distance of the object from the convex lens also impacts the size and form of the image.
