CHAPTER 2
INTRODUCTION
2
2
Introduction
The Spherical Micro Quantum Sensor US-SQS is designed to
measure photosynthetically active radiation (PAR) in suspension cu-
vettes, and specifically the photosynthetic photon fluence rate (PPFR,
see
chapter 7). The sensor consists of a 3.7 mm Ø highly scattering
plastic sphere, which detects light from all directions. It is connected
to a 2 mm Ø plastic fiber, which guides the light to a blue enhanced
silicon photodiode equipped with a special filter set for the selection
of photosynthetically active radiation between 380 nm and 710 nm.
The US-SQS/L basic sensor comes with a 3 m coaxial cable and a
BNC connector. It is connectable to any data logger with micro-
Ampere current measuring function. WALZ offers the ULM-500
(Universal Light Meter 500) for data acquisition.
In conjunction with various mechanical and electrical accessories
the US-SQS is suitable for different applications and instruments.
