Favorite Assumptions Of Lens Maker Formula

To derive lens makers formula we make the following assumptions and adopt new cartesian sign conventions.

Assumptions of lens maker formula. The formula is used to construct lenses with desired focal lengths. Only the point objects are considered. Write the basic assumptions used in the derivation of lens makers formula and hence derive this expression.

It is so called because it is used by lens manufacturers to make lenses of particular power from the glass of given refractive index. The equations are also correct when the lens are immersed in any medium provided that n is interpreted as the relative index of the material of the lens with respect to the medium. Asked Oct 18 2019 in Physics by KumarManish 577k points cbse.

The Lens Makers Formula is an expression used to find the focal length of a lens for which the refractive index as well as the radii of curvature are known. A lens maker formula may be defined as the formula which gives the relationship for calc. This is done to make ray optics calculations simpler but the first step would be to identify what constitutes thin and thick lenses.

The lens needs to be thin. The lenses whose thickness is too less to be considered as negligible as compared to the radius of curvature can be referred to as thin lenses. Ii The aperture of the lens is small.

Iv The object is a small object placed on the principal axis. Limitations of Lens Makers Formula. I The lens is thin and all the distances are measured from the optical centre of the lens.

It is a relation between the focal length of a lens to the refractive index of its material and the radii of curvature of its two surfaces. Ii The aperture of the lens is small. Basic assumptions in derivation of Lens-makers formula.