Manual Lensometer

An equipment called a manual lensometer is used to gauge a lenss optical strength. It is made up of a readout scale, a reticle, and a telescope. A sequence of lines with specified lengths serves as the reticle, which the user views via the telescope. The user then changes the readout scale until it appears that the scales lines and the reticles lines are of equal length. The optical power of the lens can be ascertained using the readout scale. An equipment used to confirm the prescription of eyeglasses or spectacles is called a manual lensometer.