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We experimentally made the high-speed drum camera which had the motor of 80,000 rounds per minutes (rpm) at rotating mirror on object beam. This paper describes results of the experiments about its basic optics, the subjects in the future and plans for improvement of the performance. The experimental monochromatic CCD image showed that the optical system employed in present study is proper basically. Additionally, this camera enable to the high-speed photography at about 520,000 frames per second, and we could show the specific policy to realize 1,000,000 frames per second in the near future

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The designs of the elastic two-dimensional plate structure are optimized for the minimal weight structures of the characteristic shapes. Structures composed of finite elements are modified discretely by attaching and detaching of elements at external boundary of shapes. In the modifications, the steepest descent method is actualized using the sensitivity function that is evaluated from the strain energy of the structure by Finite Element Method. The sensitivity value of each element is calculated by the element stiffness matrix and the nodal displacements. The two structures “A” and “B” are modified by the above mention technique. The structure “A” with vertical and horizontal displacement restraining planes is converged into a hanging bar with a uniform cross-sectional area of the minimal weight shape. The structure “B” with only vertical displacement restraining plane is converged into a V-shaped structure supported by two forked ends.