Comparison between Photo Interrupter and Giant Magnetoresistive Sensor for Auto Focusing System in the Digital Camera
Photo interrupter (PI) sensors are used to focus the lens in the optical devices such as digital camera, close circuit camera etc. It is cheap and easy to control. Despite of the advantages it has some limitations such as it is difficult to assemble, needs small tolerance and lacks high speed and accuracy. Magnetoresistive (MR) especially giant magnetoresistive (GMR) sensor provides the solution of PI sensor’s weak points. Furthermore, using GMR sensor shows better performances than PI sensor for the focusing system.
Keywordsphoto interrupter giant magnetoresistive sensor auto focus digital camera
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