Author: R. Johnson
Institution: QUEST Integrated
EUCLID: A High Accuracy, Position Compensated Laser Alignment System
EUCLID is a precision laser alignment system that is insensitive to laser beam movement during alignment operations at distance up to 300 feet (91 m). It has demonstrated great accuracy and cost savings in industrial and aerospace environments. This NAS standard system employs two or more optical targets, each of which contains an embedded processor for position sensitive detector data linearization and communication with a host controller. The targets have a one sigma (1 s) position accuracy of 80 microinches (2 microns), and a target measurement range of +/- 0.200 inches (+/-5 mm) in two axes. In its minimum configuration, it employs one see-through target and a reference target situated at the end of the line of sight. Any movement of the laser beam due to thermal effects, initial operator alignment or vibration appear as common mode errors at both targets. A real-time, similar triangle, compensation technique is performed to produce alignment data based on the line of sight as the reference datum, not the laser beam. Using an additional see through target allows for compensation of laser beam pointing and deviation. The system can be operated with a laptop computer as the monitoring station, or a rugged, graphical pendant.