Instruments Manufacturing Corporation (IMC), based in Ambala Cantt, Haryana (India), produces a device known as the Perimeter Priestly Smith—a classic physiology lab instrument used to measure the peripheral limits of human vision (i.e., perimetry)
Purpose: A manual perimeter designed for physiology or anatomy departments. It assesses the peripheral (side) vision of a subject's eye by having the observer mark the points at which a stimulus is just visible.