LI-COR LI-192 Underwater PAR Sensor
Features
- Uses computer-tailored filter glass to achieve the desired quantum response
- Sensor is cosine corrected, and calibration is traceable to NIST
- Features corrosion-resistant, rugged construction for use in up to 560m depths
- Free ground shipping
- Expedited repair and warranty service
- Lifetime technical support
- More
Overview
The LI-192 Underwater Quantum Sensor measures PAR from all angles in one hemisphere. The LI-192 works in air or underwater at depths up to 560 meters. The measurements are cosine corrected and typically expressed as Photosynthetic Photon Flux Density (PPFD). For simultaneous measurements of downwelling and upwelling PAR, two sensors can be mounted on the 2009S Lowering Frame.
Measurement Principle
The LI-192 uses a silicon photodiode and a glass optical filter to create nearly uniform sensitivity to light between 400 and 700 nm, which closely corresponds to light used by most terrestrial and aquatic plants and algae. A precision optical filter blocks light with wavelengths beyond 700 nm, which is critical for measurements in a water column, where the ratio of infrared to visible light may be high.
- Absolute Calibration: +/-5% in air traceable to NBS
- Sensitivity: Typically 4 uA per 1000 umol s-1 m-2 in water
- Linearity: Maximum deviation of 1% up to 10,000 μmol s-1 m-2
- Stability:< +/-2% change over a 1 year period
- Response Time: 10 us
- Temperature Dependence: +/-0.15% per C maximum
- Cosine Correction: Optimized for both underwater and atmospheric use
- Azimuth:< +/-1% error over 360 degrees at 45 degree elevation
- Detector: High stability silicon photovoltaic detector (blue enhanced)
- Sensor Housing: Corrosion resistant metal with acrylic diffuser for both saltwater and freshwater applications
- Waterproof: Withstands 800 psi pressure (560 meter depths)
- Size: 3.18cm Dia. x 4.62cm H
- Weight: 227g
- Mounting: (3) 6-32 holes are tapped into the base for use with the 2009S Lowering Frame or other mounting devices
- Cable: Requires 2222UWB Underwater Cable
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