How To Use An Optical Scanner Optical scanners are considered one of the most accurate and reliable methods of counting votes, and they're fairly easy to use.

Discover what an OBD2 scanner is and how to use it to diagnose and fix car problems before they escalate into major repairs.

Optical scanners may struggle when reading wet, oily, or dirty fingers, but ultrasonic scanners, like those from Goodix, work consistently in these conditions.