Object distance measuring system with dual viewing system - with alternate viewing of bright and dark images

摘要

A bright scene is viewed with one eye e.g. through a telescope and is then faded out by means of a diaphragm. The other eye then views a darker image of the same scene on a screen through a second optical system. Pref. the darker image is produced by illuminating the scene with a pulsed laser, whereby the natural light is eliminated by means of an interference filter and only the reflected light is brought to the screen by the gated viewing technique. An image intensifier is pref. used to produce the darker image.