A unique dynamic laser feedback loop allows accurate measurement without regard to speed, ambient light changes, color, and temperature of material or general plant environmental conditions. This characteristic allows the sensor to make virtually error-free measurement with total reliability and repeatability up to 16,000 times a second within a small, defined spot using very little power. The sensors are easy to maintain, install or interface with most computer and PLC systems without time consuming and costly integration. LMI Technologies Inc.