Practical test of a point-source integrating-cavity absorption meter (PSICAM): the performance of different collector assemblies

Abstract

A prototype point-source integrating-cavity absorption meter is presented and compared to spectrophotometric absorption,measurements. Different light collector assemblies of the PSICAM,were tested regarding their capability to determine the absorption of,water constituents accurately over a wide range of concentrations and,scattering properties. The PSICAM setup with a radiance-type sensor showed the best performance. It was,compared with a photometric absorption determination using,non-scattering dye solutions. The mean difference between both methods was less than 2.4 \% in the spectral range of 400 to 700 nm.,The absorption determination with the PSICAM, when equipped with a radiance sensor as a light collector, was only little affected by scattering and temperature.,We conclude that the PSICAM can be used operational for determining,the absorption of natural sea water samples at ambient temperatures.