how does camera auto focus work?
In: 126
A guy I used to know worked on one of the weirdest auto focus schemes for Polaroid. When you press the button the shutter doesn’t immediately open. It simultaneously sends an ultrasonic ping and a solenoid flips a curved rectangular lens up. The lens has a gradient focal length, and once the lens starts falling, the shutter opens when the reflected ultrasonic ping is detected. The whole thing was designed so that the focal length where the lens is falling corresponds to the distance determined by the ping. There is also a correction lens because the top of the picture will have a different focal length than the bottom due to the gradient lens. Whole thing takes a small fraction of a second so it seems instantaneous. So that’s a mechanical engineering approach to it…
Latest Answers