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Speckle patterns are produced by random interference when coherent lights scattered by a diffuse surface pass through an optical system, and their statistical properties are controlled with the change of the optical system. Using this property, a speckle random pattern with some desired statistical characteristics can be obtained, and applied to now optical techniques.

A method is shown to obtain a real image with a large image field and high resolution from an image hologram, which is produced by a large aperture lens with large amount of aberration. The resolution of the reconstructed serial image is estimated to be within the range from 450 to 500 lines/mm in 2 inch diameter image field.

Nowadays, mirrors and lenses are used that have surfaces with a deep asphericity of rotational symmetry, and there is a strong need for the precise shape measurement of these surfaces. It is not easy to measure this kind of surface by using the common interferometric method becatm the fringes are too dense to be observed. For decreasing the fringe number, a radial shear method1 is adopted.© (1987) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A multiplex hologram is synthesized by using a special optical system from an original film composed of a series of conventional photographs taken from different horizontal directions. An automatic apparatus for synthesizing multiplex holograms is built and fundamental properties of reconstructed images such as distortion and resolution are studied for both ordinary and medical objects. Some techniques to compensate the distortion are developed.© (1985) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A cylindrical holographic stereogram (CHS) is synthesized by using a series of photographs which have only the horizontal parallax, and the reconstructed image has distortions. Images reconstructed from a CHS of laser reconstruction (LCHS) and a CHS of white light re-construction (WCHS) are calculated under various conditions, and the optimum conditions for making and viewing the LCHS and WCHS are studied.

A machine for making multiplex holograms has been constructed, and optimum conditions for making and reconstructing the holograms are studied by analysing the distortion and resolution of the reconstructed images.

As one of the ultrasonic imaging techniques, a sonar system is widely used in oceanography to measure the depth of bottom and to locate schools of fish or other submerged objects. In the conventional sonar system which uses the ultrasonic pulse-echo method, the resolution limit of the object in range, the longitudinal resolution, is determined by VT/2; where V is the sound velocity in the water, and T is the duration of ultrasonic pulse, and the improvement of longitudinal resolution can be brought about by shortening the duration of pulse. But the resolution limit in angle, the lateral resolution, is λ/D; where λ is the ultrasonic wavelength and D is the dimension of the receiver; so the improvement is to be made by the increase of the dimension of the receiver by use of a special shape of the receiver, or by the choice of a shorter wavelength. This seems very difficult to realize.

An approximate treatment of partially coherent image formation is applied to projection systems, and it is concluded by both theoretical and experimental studies that the image-forming performance in this case can be treated as a special case of incoherent imagery characterized by the “stopping effect” of the effective source. The practical definition of effective source and the influence of the condenser's aberration on the image are also considered.