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A laser radar system that is capable of remotely detecting oil spills, in the daytime and at night, in sea water has been developed. The system employs the second harmonic and fourth harmonic of a repetitively Q-switched Nd:YAG laser as the light sources and a gated optical multichannel analyzer as a high speed detection device. The results show that the comparison of backscattering spectra obtained from different samples enables us to detect and characterize oil spills in sea water. Raman backscattering and backscattered fluorescence of kerosene, light oil, heavy oil, and sea water have been investigated both in the laboratory and in the harbor of Seto Inland Sea of Japan by using the laser radar system described above. The SNR of this laser radar system for the detection of Raman backscattering of kerosene and fluorescence of oil is also described.

The fundamental procedure involved in the two‐monochromator method for determining the spectral radiance factors of fluorescent materials is described, and some measured results are presented. The colorimetric accuracy of the method was confirmed by comparing two sets of tristimulus values: (1) those based on the two‐monochromator method and calculated from the reflected and the fluorescent spectral radiance factors and the spectral power distributions of a tungsten‐halogen lamp and a xenon lamp (which were determined separately); and (2) those calculated from the total radiance factors obtained from the measurement under polychromatic illumination, where the fluorescent materials were irradiated with the tungsten and the xenon lamp. The color differences between these sets of tristimulus values in CIE‐LUV color space were estimated to be less than 1.0 unit, irrespective of the illuminant or the source.

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This article describes a method for the prediction of the reflected and the fluorescent spectral radiance factor which are expected to be measured by use of a measuring system with polarizing properties, and a method for the estimation of the spectrophotometric errors in the predicted radiance factors. Polarization properties are described for the measuring system, the white standard surface, and the two kinds of fluorescent samples used in the two‐monochromator method of the present study. In this method, the spectrophotometric errors in the reflected spectral radiance factor are estimated to be not less than 1% at some wavelengths. However, the error of the fluorescent spectral radiance factor is relatively small. Colorimetric errors of fluorescent samples due to polarization are estimated for the one‐ and two‐monochromator methods. The errors expressed as CIELUV color differences are estimated to be less than 1.0 unit and are negligibly small.