CS310 Quantum (PAR) Sensor

Radiation that drives photosynthesis is called photosynthetically active radiation (PAR) and is typically defined as total radiation across a range of 400 to 700 nm. PAR is often expressed as photosynthetic photon flux density (PPFD): photon flux in units of micromoles per square meter per second (µmol m-2 s-1, equal to microEinsteins per square meter per second) summed from 400 to 700 nm (total number of photons from 400 to 700 nm). While Einsteins and micromoles are equal (one Einstein = one mole of photons), the Einstein is not an SI unit, so expressing PPFD as µmol m-2 s-1 is preferred. 

Sensors that measure PPFD are often called quantum sensors due to the quantized nature of radiation. A quantum refers to the minimum quantity of radiation (one photon) involved in physical interactions (for example, absorption by photosynthetic pigments). In other words, one photon is a single quantum of radiation. 

Typical applications of quantum sensors include incoming PPFD measurement over plant canopies in outdoor environments or in greenhouses and growth chambers, and reflected or under-canopy (transmitted) PPFD measurement in the same environments. 

The CS310 quantum sensor consists of a cast acrylic diffuser (filter), photodiode, and signal processing circuitry mounted in an anodized aluminum housing with a cable to connect the sensor to a measurement device. The CS310 quantum sensor is designed for continuous PPFD measurement in indoor or outdoor environments. It outputs an analog signal that is directly proportional to PPFD. The analog signal from the sensor is directly proportional to radiation incident on a planar surface (does not have to be horizontal), where the radiation emanates from all angles of a hemisphere. 

Benefits and Features 

• • Full-spectrum quantum sensor with a spectral range of 389 to 692 nm (±5 nm) 
  • Accurate measurements under all light sources including Light Emitting Diodes (LEDs) 
  • Dome-shaped anodized aluminum body designed to be rugged and self-cleaning for a longer life and lower maintenance 
  • IP68 rated connector provides extra assurance in wet and harsh environments 
  • Sensor head detachable from the cable with a marine-grade 316-L stainless-steel connector for fast, easy servicing 
  • Factory calibration data stored in the sensor so no sensor-specific calibration coefficients required for an accurate measurement 
  • Each sensor carefully calibrated in controlled conditions and traceable to NIST reference standards 
  • Four-year manufacturer warranty