Methods of Reducing Spherical Aberration

How to Reduce Spherical Aberration The following 5 methods are usually used to reduce the spherical aberration. By Stop Method. By using plano-convex lenses. By using two convergent lenses separated by a finite distance. By using crossed lens. By using the combination of suitable concave and convex lens. By Stop Method Since spherical aberration of … Read more

Aberration in Optics and Types of Aberration

Aberration in Optics In the simple theory of image formation by lenses, it is assumed that an object is situated very close to the principal axis and each point object produces a corresponding point image. In other words, a lens produces a perfect or an ideal image of an object. But in reality, a lens … Read more

Combination of Lenses

Combination of Lenses

Suppose we have two lenses of focal lengths f1 and f2 separated by a distance x as shown in fig below. L1, L2 correspond to the position of two lenses while the transverse planes through L1 and L2 will serve as input and output planes respectively. AB is the incident ray and CD is the … Read more

Translation Matrix

Translation Matrix

The matrix Tm is called Translation Matrix. The matrices can be used to find the position of the final image. The method of writing linear equations for the coordinates of the paraxial rays and then transforming them into the matrices for the purpose of optical analysis is called Matrix method in optics. When a ray … Read more

Fermat’s Principle of Least Time

Fermat's Principle of Least Time

What is fermat’s principle? This principle states that the light always travels that path in a medium from one point to another point which takes the minimum (i.e least) time. Fermat’s Principle of Least Time Consider a medium of refractive index n. The time taken by light ray to travel a distance dS in the … Read more

Optical Path and Geometrical Path

The branch of physics which deals with the study of optical phenomenon like reflection, refraction, dispersion, interference, diffraction, polarization etc. is known as optics. Optics is classified into two categories: the geometrical optics and physical optics. Geometrical optics is a branch of optics which deals with the study of optical phenomenon without considering the nature … Read more