Tomohiko Oishi

Quick and easy measurement of particle size of Brownian particles and plankton in water using a self-mixing laser

We describe a method for quickly and easily measuring the size of small particles in suspensions. This method uses a self-mixing laser Doppler measurement with a laser-diode-pumped, thin-slice LiNdP(4)O(12) laser with extremely high optical sensitivity. The average size of the particles in Brownian motion is determined by a Lorentz fitting of the measured power spectrum of the modulated self-mixing laser light resulting from the motion. The dependence of the measured power spectra on particle size and concentration was quantitatively identified from the results of a systematic investigation of small polystyrene latex particles with different diameters and concentrations. The sizes and ratios of particles with different diameters mixed in water were accurately measured. An application of this self-mixing laser method for estimation of the average size of plankton in seawater showed that it is a practical method for characterizing biological species.

In-Water Algorithms for ADEOS/OCTS

AbstractIn-water algorithms for OCTS standard products were developed using in situ data and installed for operationally processing at NASDA/EOC. This paper describes the in-water algorithms Version 1.0 for chlorophylla concentration, pigment concentration, and attenuation coefficient at a wavelength of 490 nm. The selected OCTS standard algorithms (Ver. 1.0) are as follows:

A new approach to measure the volume scattering function

Chl = 0.2818 \left( {\frac{{L4 + L5}}{{L3}}} \right)^{3.497 }

Application of neural network method to case II water

Pig = 1.568 \left( {\frac{{L2}}{{L4}}} \right)^{ - 2.079 } \left( {\frac{{L3}}{{L4}}} \right)^{ - 3.498 }