An optical instrument which operates with an incident optical beam scanned at high rates and with correspondingly small sized scanning devices, has a double-scanning optical system. The output reflected beam that is detected overfills the first-stage scanning element, yet the instrument attains a relatively high-contrast image. The instrument provides for astigmatism correction, graphic generation in the scanned beam, and the use of infrared wavelength laser beams as well as visible wavelength laser beams. It also provides for generating system timing pulses from a rotating scanning element.