max. depth 560m
The LI-192 Underwater Quantum Sensor measures photosynthetically active radiation (PAR) from all angles in one hemisphere. The LI-192 works underwater at depths up to 560 meters. The measurements are cosine corrected and typically expressed as Photosynthetic Photon Flux Density (PPFD).
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 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.
Technical data:
- Pressure resistance: 560 dbar
- Absolute calibration: 5 % in air
- Sensitivity: typ. 4 μA per 1,000 μmol/s m² in water
- Linearity: max. deviation of 1% up to 10,000 μmol/s m²
- Response time: 10 μs
- Temperature dependence: ± 0.15% per °C maximum
- Azimuth: < ± 1 % error over 360° at 45° elevation
- Operating temperature: -40°C…65°C
- Principle: Quantum sensor
- Used for: CTD75M, CTD90, CTD90M, CTD115M
