What is the difference between a convex lens and a concave lens? Convex lens imaging rules

Contents of this article

1. Distinguishing between convex lens and concave lens

2. What is the imaging law of convex lens?

3. What happens when a convex lens and a concave lens are placed together?

Distinguishing between convex lens and concave lens

In fact, convex lenses and concave lenses can be distinguished by their different compositions, applications, and effects. Convex lenses are a refraction phenomenon. The lens is thick in the middle and thin on both sides. The image formed is inverted and reduced, and it has a focusing effect on light. Hyperopia glasses are convex lenses, while concave lenses are thin in the middle and thick on both sides. Myopia glasses are concave lenses.

Convex lens

Generally speaking, the main difference between convex lens and concave lens is their composition, and their principles are opposite. Convex lens is called positive spherical lens, which is very thick in the middle and very thin on both sides, and is mainly convex in shape, and has the effect of converging light, while concave lens is very thin in the middle and very thick on both sides, and is concave in shape.

concave lens

A convex lens is an image formed by the actual light produced by the reflection or refraction of an object. The image formed in the convex lens is inverted and reduced. Hyperopia glasses are convex lenses, while concave lenses are images formed by the reverse extension of light. They are mainly used in solar cookers, table lamps, etc. Myopia glasses are also concave lenses.

Convex lens

A convex lens is a refractive image. The image it forms can actually be viewed directly with the naked eye or received on a light screen. It can generally be tested with a light bulb. A convex lens can produce parallel light rays, while a concave lens cannot. A concave lens is a reflective image, and the image it forms is a virtual image.

What is the imaging law of convex lens?

The imaging law of a convex lens is that when an object is placed outside the focus, an inverted real image is formed on the other side of the convex lens. Real images can be divided into three types: reduced, equal-sized, and enlarged. It has a converging effect on light and is an optical law. The image that can be presented on the light screen is called a real image.

The imaging law of a convex lens is that when an object is placed outside the focus, an inverted real image is formed on the other side of the convex lens. Real images can be divided into three types: reduced, equal-sized, and enlarged. It is an optical law. The image formed by the convergence of actual light and that can be presented on a light screen is called a real image.

When distinguishing between real and virtual images, you can check whether the image is upright or inverted. Real images are inverted, while virtual images are upright. Lenses can be divided into convex lenses and concave lenses. Convex lenses are thinner at the edges and thicker in the middle. At least one surface must be made into a spherical surface.

A concave lens is thick at the edges and thin in the middle. At least one of its surfaces is made of a spherical surface. It mainly has a diverging effect on light and can only form a positive, reduced virtual image. The convex lens mainly has a converging effect on light.

What happens when you put a convex lens and a concave lens together?

Convex lenses and concave lenses can be put together to make a telescope, thereby increasing the visual angle of an object to the human eye. The real image formed by the refraction of light through the telescope objective lens will be at a focus behind the eyepiece, which is a virtual image for the eyepiece. After refraction, it will become an upright virtual image.

We all know that convex lenses and concave lenses are two different things. They have their own characteristics. For example, convex lenses use refraction to form images and have a converging effect on light, while concave lenses use reflection to form images and have a emitting effect on light.

If convex lenses or concave lenses with different focal lengths are put together, a telescope can be made to increase the visual angle of objects for the human eye. The famous Galileo telescope is composed of these two, and its objective lens is made up of a combination of convex lenses and concave lenses.

The combination principle of this telescope is extremely reasonable. The real image formed by the refraction of light through the objective lens will be at a focus behind the eyepiece, which is a virtual image for the eyepiece. After refraction, it will become an upright virtual image.