The LI-193 Spherical Quantum Sensor measures PAR in air or underwater from all directions at depths up to 350 meters. This sensor is useful for studies of phytoplankton, which uses radiation from all directions. The measurement is referred to as Photosynthetic Photon Flux Fluence Rate (PPFFR) or Quantum Scalar Irradiance.Request a Quote Download Brochure
The LI-193 uses a diffusive sphere to direct light through glass optical filters to the silicon photodiode. The filters create uniform sensitivity to light between 400 and 700 nm, which closely corresponds to light used by most terrestrial and aquatic plants and algae. The angular response of a typical LI-193 is slightly lower in the direction of the cable connection. When mounted, the low response is usually not significant due to the small proportion of upwelling radiation compared to the total.
LI-193 cables are available in lengths from 3 meters to 100 meters.
We recommend the 2009S Lowering Frame to lower the sensor into water.
Back to Light Measurement Products