Lens Maker Formula
The lens maker’s formula is an equation used to relate the focal length (f) of a lens to its refractive index (n) and the radii of curvature (R1 and R2) of its two surfaces. It helps us understand how the shape and material of a lens affect its ability to focus light.
1/f = (n – 1)×(1/R1 – 1/R2)
where,
- f is the focal length of the lens (in meters)
- n is the refractive index of the lens material (a dimensionless quantity)
- R1 is the radius of curvature of the first surface (in meters) (positive for a convex surface, negative for a concave surface)
- R2 is the radius of curvature of the second surface (in meters) (positive for a convex surface, negative for a concave surface)
Ray Optics – Definition, Formula, Applications
Ray Optics is the study of properties of light and optical instruments by assuming that light travels in a straight line. It is also known as geometrical optics, which deals with the geometry of light. Light always travels in a straight line, and the direction in which the light rays propagate is called the ray of light. It studies the principles and laws governing the propagation of light, particularly in the absence of wave effects such as interference and diffraction.
In this article, we will learn about ray optics, reflection, refraction, concave and convex mirrors, lenses, and formulas related to them.