What is camera autofocus?

Lead: With the development of digital technology, digital technology has appeared among us. What is autofocus? Auto-focus, also known as auto-focus and auto-focus, refers to a focusing method that is not recognized by the naked eye. For example, it is controlled by photoelectric imaging system, or focused by infrared and ultrasonic ranging.

What is camera autofocus? Since the advent of 1977 Konica C35 autofocus (AF) camera, various camera companies have announced various autofocus mechanisms. The contrast detection method of Hanay Houyel Company in the United States is based on the continuous test of image contrast, which uses the output of photoelectric system to control the camera lens to focus on the best contrast of the image.

Canon's near-infrared method and Polaroid's sonar autofocus method are autofocus methods that emit infrared (the former) and ultrasonic (the latter), and reflect after shooting the object. Time is measured by a synchronous oscillator, and then converted into a distance signal, which is connected with the lens. Near infrared and sonar (ultrasonic) methods can automatically focus in dark places, such as complete darkness.

Before the above automatic focusing (AF) method came out, the focusing method of rangefinder linkage camera or dual-lens reflex camera with rangefinder linkage camera and photographic lens was once called autofocus, but it was actually manually operated, which should be different from the autofocus of modern AF cameras.