UDT Instruments autocollimators operate on the same principle as classical models — except that a position-sensing photodiode replaces the human eye.
A high-power infrared LED operating at 865 nm (±45 nm) inside the instrument generates a beam of light. It is reflected through a beamsplitter, and then lens-collimated. When this beam reflects off a reference mirror on an object under test, it then travels back through the lens and beamsplitter to the position sensing-detector.
Changes in the position of the incident beam on the photodiode are directly proportional to changes in the angle of the reference mirror. The focal length of the lens determines the angle of coverage. An internal blocking filter for visible light less than 780 nm prevents ambient light from interfering with the measurement.
Our vacuum-compatible models (V series) are ideal for testing satellite optical systems in a simulated space environment.
Autocollimator System Applications
- Mirror Alignment
- Optical Component Testing
- Testing of Machine Surfaces
- Structural Flexure Measurements
- Vibration/Stability Measurements
- Servo Control
uSENS-A Electronic Autocollimator System
This bundle combines a standard electronic autocollimator with with an analog position indicator to provide non-contact measurement of the angular position of a reference surface. This enables highly-accurate measurement of flatness, parallelism, and surface orientation.
Measurement results are displayed by the position indicator, and analog data can be monitored via the indicator’s BNC and TTL outputs. Gain and offset adjustment for each channel enables application-specific user calibration based on a NIST-traceable standard optical wedge.
- Model 431 Position Indicator: 2-axis, Analog; direct readout; 7 kHz sampling rate; BNC and TTL output
- Model 1010 Autocollimator: Wide angular coverage; 1 arc-second resolution; internal LED source (865 nm); bandpass filter
- Calibration Standard: NIST-traceable optical wedge to support simple, accurate user calibration
UDT Instruments Autocollimators
|Beam Diameter||25 mm||25 mm||25 mm||25 mm||25 mm||25 mm||Overall Length||140 mm||140 mm||140 mm||140 mm||140 mm||140 mm|
|Barrel Diameter||38.1 mm||38.1 mm||38.1 mm||38.1 mm||38.1 mm||38.1 mm||Weight||1.52 kg||1.52 kg||1.52 kg||1.52 kg||0.59 kg||0.59 kg|
|Max Working Distance||9 m||9 m||9 m||9 m||1 m||1 m||Max Angular Coverage|
|Full Angle at 1 Meter||300 arc-sec||80 arc-sec||300 arc-sec||80 arc-sec||300 arc-sec||60 arc-sec||Full Angle at 3 Meters||300 arc-sec||30 arc-sec||300 arc-sec||30 arc-sec||N/A||N/A|
|Full Angle at 9 Meters||150 arc-sec||10 arc-sec||150 arc-sec||10 arc-sec||N/A||N/A||Accuracy with Model 531|
|Accuracy at < 10 arc-sec||0.001 arc-sec||N/A||0.01 arc-sec||N/A||0.1 arc-sec||N/A||Accuracy at > 10 arc-sec||0.1 arc-sec||N/A||0.1 arc-sec||N/A||0.1 arc-sec||N/A|
|Accuracy at < 600 arc-sec||N/A||0.06 arc-sec||N/A||0.06 arc-sec||N/A||1.0 arc-sec||Accuracy at > 600 arc-sec||N/A||6.0 arc-sec||N/A||6.0 arc-sec||N/A||6.0 arc-sec|
|Linearity in Angular Coverage||Central 10% of Coverage||< 5%||–||< 5%||–||< 10%||–|
|Entire Angular Coverage||< 20%||< 10%||< 20%||< 10%||< 30%||< 10%||Axial Beam Concentricity||< 5 arc-min||< 5 arc-min||< 5 arc-min||< 5 arc-min||N/A||N/A|
|Temperature Coefficient of Drift (10°C < T < 35°C)||< 0.5 arc-sec/C°||< 0.5 arc-sec/C°||< 0.5 arc-sec/C°||< 0.5 arc-sec/C°||N/A||N/A||Outgassing Test Performance: Molecular Contamination < 0.7 x 10-7 g/cm3 for 24 hrs at 1.0 x 10-5 mBar; (10°C < T < 35°C)||N/A||N/A||Yes||Yes||N/A||N/A|
|Calibration Wedge||Model 1359-2, 30 arc-sec||Model 1359-1, 15 arc-min||Model 1359-2, 30 arc-sec||Model 1359-1, 15 arc-min||Model 1359-2, 30 arc-sec||Model 1359-1, 15 arc-min||Select 531 Detector Mode||Quadrant||Duo Lateral||Quadrant||Duo Lateral||Quadrant||Duo Lateral|