What is the auto-focus auxiliary light of digital camera?

Introduction: Many manufacturers of digital cameras will install a small round lamp next to or above the lens barrel of their digital cameras. What is the function of this round lamp? In fact, this is an auto-focus auxiliary lamp, which is responsible for illuminating the subject for the camera's focusing system in a poor light environment, so that the focusing system can focus accurately. The power of the autofocus auxiliary light is relatively small, and it usually only works in a short range (generally not more than 4 meters). Some advanced autofocus auxiliary lights even use infrared lamp instead of traditional auxiliary lights that emit visible light. Because the infrared lamp emits invisible infrared rays, the subject can't notice its existence, so it brings great convenience for candid shots and snapshots. It is worth noting that the autofocus auxiliary lights used in some high-end external flash systems are usually of high power and can work in a wider range. What is the autofocus auxiliary light of digital camera

The autofocus auxiliary light of Canon Power Shot S5 is placed above the lens and next to the flash. Placed in this position has a dual role. First of all, the auxiliary lamp can emit a special white light to help the autofocus system lock the focus on the subject in a dim environment; Secondly, when the camera turns on the anti-red eye function of the flash, as long as the user presses the shutter half to focus, the auxiliary light will emit light at the same time to illuminate the pupil of the subject to prevent the occurrence of red eye.

Some Sony digital cameras are equipped with holographic autofocus system. In this system, the auxiliary light will project a cross laser beam on the subject to help the camera detect and determine whether the focus is successfully locked on the subject. As long as the subject is large enough (can be detected by the system), this system can play a powerful role.