Transmittance (Sea-Bird)
RBR standard instruments support the Sea-Bird transmissometers (C-Star).
Fig. 78. Transmissometers (Sea-Bird)
These sensors measure underwater light transmittance by projecting a collimated beam through an optical flow tube and quantifying its attenuation. As the loss of light occurs due to scattering and absorption, the resulting value reflects the concentration of organic matter suspended and dissolved in seawater.
| Parameter | Value |
|---|---|
Wavelengths |
410 / 465 / 520 / 650nm |
Bandwidth |
~10-12nm for 370nm |
Pathlength |
25 or 10cm |
Acceptance angle |
~1° |
Bandwidth |
~10-12nm for 370nm |
Linearity |
99% R2 |
Depth rating |
600m (plastic), 6000m (aluminium) |