Third party instrument calibration and measurement center provides inspection and calibration services

Third party instrument calibration and measurement center provides inspection and calibration services

The following are the general procedures for calibrating laser interferometers:

Pre-calibration preparation

Environmental condition control: The temperature should be controlled within the range of 20 ℃± 2 ℃, and the fluctuation during calibration should be small. Air conditioning or constant temperature equipment can be used; Maintain humidity between 40% -60% and adjust it through dehumidification or ventilation equipment; Place the instrument on an isolation platform that is level and away from the vibration source.

• Instrument preheating: Preheat according to the instructions of the instrument, usually by turning on the machine and preheating for more than 20 minutes to reach a stable working state.

• Cleaning of optical components: Gently wipe the optical windows and mirror surfaces of the laser emitter and receiver with anhydrous ethanol and lens paper.

Third party instrument calibration and measurement center provides inspection and calibration services

Calibration items and methods

Laser wavelength calibration: Using a standard or reference ruler of known length as a reference, such as a high-precision gauge block. Start the instrument, let the laser pass through the standard fixture, measure the number of interference fringes of the laser at the standard length, and calculate the actual wavelength through multiple sets of data. If there is a deviation from the theoretical value, adjust it through the adjusting device.

Third party instrument calibration and measurement center provides inspection and calibration services

• Straightness calibration: Install the device under test on a linear guide, fix the reflector at the end, and adjust the laser emitter to make the laser beam parallel to the guide. Move the device under test, the reflector moves back and forth along the guide rail, the interferometer collects interference fringe data and converts it into displacement data, analyzes the straightness error, and adjusts the device installation position or mechanical structure if it exceeds the range.

Optical path calibration: Check the laser path to ensure that the interferometer and reflector are installed correctly and aligned accurately. By adjusting the relevant components, the laser beam can accurately propagate and reflect, ensuring that the optical path deviation is within the allowable range. For some laser interferometers, specific steps need to be taken to adjust the optical path. For example, for the American optical laser interferometer, it is necessary to adjust it from near to far first, so that the reflected light can be recombined and enter the return hole to ensure that the light intensity indicator light is fully on.

Post calibration processing

After the calibration is completed, fill in the calibration record, which includes the calibration date, personnel, instrument model and number, calibration items, results, etc. According to the calibration results, attach corresponding labels to the instrument. If it is qualified, attach a qualified label. If it is unqualified, it needs to be repaired and recalibrated.