LI-190 Quantum Sensor, LI-COR Biosciences (CAT#: STEM-LE-0216-LC)

Because the LI-190's spectral response is tailored by the computer, accurate measurement results can be obtained under all natural and artificial lighting conditions. Colored glass filters are used to adapt the silicon photodiode response to the required quantum response. An interference filter provides a steep cutoff at 700 nm, which is critical for measurements under vegetation where the ratio of infrared to visible light may be high. A small response in the infrared region can lead to significant measurement error. This sensor was developed according to the early work, first developed by LI-COR, and has become the standard for PPFD measurement in most research related to photosynthesis.
In the field of oceanography, forestry, and marine science, LI-190 is also used as a reference sensor for comparison with the underwater PAR measured by the LI-192 Underwater Quantum Sensor and LI-193 Spherical Underwater Quantum Sensor.

Sensitivity: Typically 5 µA per 1000 µmol s-1 m-2 in water
Detector(s): High Stability Silicon Photovoltaic
Response Time: 10 usec
Linearity: Max. Dev. 1% up to 10,000 µmol s-1 m-2