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This article describes a new monochromatic x‐ray CT system using synchrotron radiation with applications in biomedical diagnosis which is currently under development. The system is designed to provide clear images and to detect contrast materials at low concentration for the quantitative functional evaluation of organs in correspondence with their anatomical structures. In this system, with x‐ray energy changing from 30 to 52 keV, images can be obtained to detect various contrast materials (iodine, barium, and gadolinium), and K‐edge energy subtraction is applied. Herein, the features of the new system designed to enhance the advantages of SR are reported. With the introduction of a double‐crystal monochromator, the high‐order x‐ray contamination is eliminated. The newly designed CCD detector with a wide dynamic range of 60 000:1 has a spatial resolution of 200 μm. The resulting image quality, which is expected to show improved contrast and spatial resolution, is currently under investigation.

Fluorescent scanning (FS) x‐ray tomography was developed to detect nonradioactive tracer materials (iodine and gadolinium) in a living object. FS x‐ray tomography consists of a silicon (111) channel cut monochromator, an x‐ray shutter, an x‐ray slit system and a collimator for detection, a scanning table for the target organ, and an x‐ray detector with pure germanium. The minimal detectable dose of iodine in this experiment was 100 ng in a volume of 2 mm3 and a linear relationship was shown between the photon counts of a fluorescent x ray and the concentration of iodine contrast material. A FS x‐ray tomographic image was clearly obtained with a phantom.

An optical scanner using the principle of light reflection has been designed for determining directional slope distributions of the wind‐disturbed water surface. The instrument has been tested successfully in the laboratory and could be used in the field. Some sample results along with procedures for data analysis are also presented.

An optical instrument, utilizing a light reflection principle, has been designed which is capable of determining not only surface slope, but also surface curvature distribution. This instrument has been successfully tested in laboratory studies of wind generated waves. Some sample results are included to illustrate the applicability of the instrument.