Designed for portable laser measurement and calibration, Renishaw's XL-80 laser measurement system features a compact laser head and an independent compensator system. The system uses interferometry as the basis for all its measurement options, and its integrated USB eliminates the need for a separate laser-to-PC interface. Laser frequency stability is ±0.05 ppm over 1 year and ±0.02 ppm over 1 hour. This performance is achieved by dynamic thermal control of the laser tube length to within a few nanometers. The system maintains ±0.5-ppm linear measurement accuracy from 32º to 104ºF over the full air pressure range. Maximum travel velocity is 4 m per second, and linear resolution is 1 nm at maximum velocity.
The system's XC-80 compensator features “intelligent sensors” that process readings at source. After measuring air temperature, air pressure and relative humidity, the compensator modifies the nominal value of the laser wavelength to give a true value. According to the company, this can reduce measurement errors. This operation can be performed automatically every 7 seconds. Each sensor shuts down between readings to minimize heat dissipation. In addition, both the air and material temperature sensors are “intelligent.” Integral microprocessors analyze and process the sensors’ before sending digital temperature values to the compensator, allowing the overall system to have a more compact design.