In 1981 Dr Ting-I Wang, working at the NOAA ERL Wave Propagation Laboratory, published a seminal paper: Wind Measurements By Temporal Cross-Correlation Of Optical Scintillations, showing how this method could be used to measure changes in air flow by analysing the movement of air through a beam of light. Other papers refining this approach soon followed, along with grant of original US patents using this approach for atmospheric data collection.
In 1985, with other venturesome individuals, Dr Wang incorporated Scientific Technology, Inc. to develop this technology – resulting in the ground-breaking LEDWI (Light-Emitting Diode Weather Indicator). Further research and development followed with a corporate name change to Optical Scientific, Inc. (OSI) in 2000, to more accurately convey the broader scope of product offerings. Since then, OSI has further expanded operations to include full-scale AWOS AV, MAWOS, and portable systems. Today, OSI produces weather sensors and systems for scientific, industrial, aerospace, military, and commercial customers worldwide.
Despite the growing technical sophistication and interconnectedness of today’s infrastructure, the challenge of predicting and coping with changing weather patterns and extreme events remains formidable. The increasing advent of unprecedented weather phenomena makes the need more critical than ever. Expanding travel and commerce by air and sea, the trend of population shifting to coastal and flood plain areas, and the accelerating dependence on intensive farming methods to feed the world’s population means a growing need for and dependence on reliable, precise data for weather model calculations and forecasting. OSI’s optical scintillation-based present weather sensors still remain the best tools for the job.
“the APG-815 (All-Precipitation Gauge) is the latest offering in a long line of advanced sensors”


APG-815 not only overcomes the inherent limitations of conventional rain gauges, it reports differing types of precipitation and operates in conditions where others cannot.
OSI Continues Advancements In Atmospheric Sensing The APG-815 samples the atmosphere directly using a modulated infrared light beam. The scintillations in the sample volume are detected, amplified, and averaged using an intelligent algorithm developed and refined using over 25 years of direct observation data. The result? Unsurpassed accuracy in precipitation measurement.
APG-815 features:
- Enhanced measurement of instantaneous precipitation: rainfall from 0.1mm/hour to >500mm/hour
- Calibrated water equivalent snow rate and accumulation output • No overflow or mechanical limits
- Automatic correction and continuous internal monitoring
- No moving parts – operates unattended 24/7/365
- Wind and slant path rain errors are negligible
- Functions in all weather
- No antifreeze required
- Flexible mounting, even on moving platforms (buoys / shipboard)
- AC line, battery or solar powered
- Ultra-low maintenance
- Multiple data interfaces to match user requirements
APG-815 can function as a stand-alone unit, or can be easily integrated with an existing array, or as part of a complete OSI – provided AWOS system.
OSI was founded with the intention of putting our unique methodology to work in providing our customers with the best possible instruments – whatever the task. We are proud to contribute our expertise to the welfare of the global community.
+01 301 963 3630 [email protected] opticalscientific.com