Autofocus distance-measuring optical system

摘要

An autofocus distance-measuring optical system includes a sighting telescope having an objective lens for sighting an object; an optical distance meter which includes a light-transmitting optical system for transmitting a measuring light via the, and a light-receiving optical system for receiving light reflected by the object; a focus detecting device for detecting a focus state of the sighting telescope; and a controller for controlling the sighting telescope to automatically focus on the object in accordance with the focus state detected by the focus detecting device. The focus detecting device is a phase-difference detection type which detects an in-focus state from a pair of images respectively formed by two light bundles which are passed through two different pupil areas. The two different pupil areas are positioned so as not to interfere with any optical elements of the optical distance meter.