MKS Instruments, Inc., a global provider of technologies that enable advanced processes and improve productivity, has announced the Ophir® Wide Beam Imager SWIR (WB-I SWIR), a compact, calibrated optical system for measuring the size and power distribution of large and divergent beams of VCSELs and LEDs in the SWIR range (900 - 1700 nm).
Image Credit: MKS Instruments, Inc.
Current methods of profiling wide and divergent SWIR wavelength beams provide inaccurate results due to the high angle dependence of the sensor, or require bulky and expensive laboratory equipment that is not suitable for field operation or production environments.
The WB-I SWIR profiler, when combined with Ophir BeamGage software and an InGaAs camera, is capable of imaging any beam shape (round, line, square, or doughnut) that is too large for a camera sensor. It features a 45 mm diameter aperture and can accurately measure beams with an angle of incidence up to 70 degrees (compare with 15 degrees for standard beam profilers). Beams are captured on a translucent diffusive screen and then re-imaged to produce a complete and accurate mapping of the light's intensity distribution. The WB-I SWIR profiler is designed for use with camera-based beam profiling systems in such areas as eye-safe applications using IR VCSELs or diodes, automotive LIDAR, facial and gesture recognition, and remote sensing.
"Large or diverging beams present special challenges because the apertures of conventional beam profilers are too small to collect the entire spot," said Reuven Silverman, General Manager, Ophir Photonics. "In addition, the quantum efficiency of traditional beam detectors is highly affected by the angle of incidence. The quantum efficiency recedes dramatically with angles of incidence as high as 20 degrees, causing significant measurement errors. The WB-I SWIR is a calibrated device that can handle beam angles up to 70 degrees. It captures the beam and images its power distribution onto the camera with an accuracy of better than ±5%."
Similar to it's sister product, the WB-I device, which measures UV, VIS, and NIR beams in the 350 - 1100 nm range, the WB-I SWIR profiler is a compact device that is quick to install, easy-to-use, and dust-proof. Unlike low accuracy, do-it-yourself devices or slow and expensive goniometers, the WB-I SWIR produces images with reduced speckle and high accuracy measurements of power distribution.
The WB-I SWIR profiler is supported by Ophir BeamGage Professional software, the industry's most advanced beam analysis system. BeamGage is based on Ultracal, Ophir's patented, baseline correction algorithm that helped establish the ISO 11146-3 standard for beam measurement accuracy. BeamGage software includes all the calculations needed to make accurate, ISO approved laser beam measurements, including total power, peak fluence, ellipticity, goodness of fit, and more. The software provides advanced image processing features, NIST-traceable power measurements, trend charting, data logging, pass/fail production testing, and multilingual support for English, Japanese, and Chinese. Advanced features include partitioning of the camera output for separate analysis of multiple laser beams from sources such as fiber, a .NET interface for full remote control when integrating beam analysis into an automated application, and camera sharing.
When used together, the WB-I SWIR profiler, BeamGage software, and the Ophir SP1203 InGaAs camera can provide real-time beam shape analysis and visualization. That means changes of the beam shape due to different applied currents can easily be detected.