 It proved successful among similar cameras from the competition and sold well; production reached 110,000 per month by the second half of 1981.It was partly supplanted by 1981's higher-specified AF35ML and wholly replaced by 1983's AF35M II.The active autofocus system used a near-infrared emitting diode and a pin photo diode to determine the subject position by triangulation in a manner similar to a coincident-image rangefinder.