A lens is a type of optical instrument. Which works on the principle of refraction of light.
Lenses are used in almost all light illuminator devices. For example, lenses are used in cameras, projectors, telescopes, microscopes etc. Lanes are mainly made of glass but some lenses are also made of plastic etc.
Type Of Lens
- Convex lens or (Converging lens)
- Concave lens or (Diverging lens)
Convex lens or (Converging lens)
The convex lens is thick in the middle and thin at the edges. When a light beam passes through a convex lens, a space is collected. A lens can have both spherical or one-page spherical and the second page flat.
Convex lens has positive focus distance.
There are three types of convex lenses –
1) Biconvex lens
2) Plano convex lens Biconvex Lens
3) Concavo-convex lens.
Concave lens or (Diverging lens)
The concave lens is thin at the middle and thick at the edges. A ray of light passes through a concave lens. Then she spreads. This is why it is used in the headlights of trains to see more distances. Biconvex Lens
The focus distance of a concave lens is negative.
Similarly, concave lenses are also of three types –
1) Biconcave lens
2) Plano-concave lens
3) Convexo-concave lens.
Refraction in Lens
When a ray of light passes through a lens. Then there is refraction of the light beam twice. The first refraction occurs when the beam enters the lens. And the second refraction occurs when the beam comes out of the lens Biconvex Lens
Each surface of the lens is part of a sphere. The center of this sphere is called the center of curvature of the surface. Because each lens has two surfaces, each lens has two curvature centers. And there are also two curvature radii. There is no need to have both radii equal. Biconvex Lens
What is the focus distance of the lens?
The focus distance of the lens is the distance between the optical center and the main focus, often represented by f. The focus distance of a curved lens with a higher curvature is shorter than the focus distance for a thin lens with a lower curvature. Biconvex Lens
Focus distance of lens (f) = 1 / P,
When f is measured in meters, the p unit diopter (D or m ^ -2) is called. Its S.I unit is diopter.
What is the capacity of lens
The brightness of the lens is expressed by the distortion of its focus distance. If the power and focus of the P and F lenses are different,
• Lensivity (P) = 1 / f,
Prism Biconvex Lens
A prism is called a transparent medium that lies between two plane planes inclined at an angle, ie a prism is a transparent medium between plane planes inclined at an angle. The angle between the refractive surfaces is called the prism angle and the line joining the two cells is called the refractive core. Biconvex Lens
The rays incident on the prism deviate from their path. Thus, the angle formed between the incident ray and the output ray is called the deviation angle of the light ray. Biconvex Lens
The value of the angle of deviation depends on the incidence angle, the substance of the prism, the wavelength of heat and light.
If the prism of a prism is A and the minimum deviation is delta M, then the refractive index of the prism substance
When white light passes through an opaque medium, it splits into its element colors, this phenomenon is called character deflection.
This is due to the difference in the wavelength of the colored dyes. Seven colors of white light are obtained when it comes out of the prism. Which are purple, sky, blue, green, yellow, orange, and red respectively.
The purple color has the lowest wavelength and the red wavelength is the highest in the spectrum obtained by prism, which leads to purple color at the top and red color at the bottom of the spectrum.
|Color||Wavelength Angstog (Å)|
Color of Objects
The color of an object refers to its tendency to absorb or transmit the component colors of light. The color of the object seen in sunlight is called the natural color of that object. The color of the object depends on the wavelength of light incident on it. Does.
Transparent Object’s colors
The color of which the rays get refracted from the transparent object is the color of the object
Opaque Object’s colors
When white light is incident on a colored opaque object, it absorbs some part of the object light and reflects some part of the object, the color of the object being reflected is the color of the object.
For example, when you see a green object in green light, it appears green because it has reflected the green color and absorbed all the colors. The green color absorbs all the light in the light of red and hence appears to be black.
Primary color and Secondary color
Basic colors are those colors which are not obtained with the help of any other colors. These are the Primary colors. Other colors are obtained by mixing the Primary colors in different proportions. Blue, green and red have been labeled as the Primary colors,
- Red + green = yellow
- Red + blue = purple
- Blue + Green =
Secondary colors are obtained by mixing two or more primary dyes.
Complementary colors are those colors, which we get white color by mixing together.