The aberrations are synthesized by arranging three computer-generated holograms (CGHs) in serial geometry which generate coma, astismatism and spherical aberration, respectively. The diffraction patterns suffering form third-order combined aberration are reconstructed and compared with the numerical ones. There is good agreement between experimental and theoretical results. The relation between the maximum amount of aberration to be reconstructed and the required sample number of CGH is discussed.

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The distortion of the reconstructed image from a cylindrical holographic-stereogram is due to the geometrical arrangements in making of the stereogram and observing the reconstructed image.
We derived the equations which determine the 3-D shape of the reconstructed images, and as an example We calculated the 3-D distortion of a cubic frame by computer. Then we investigated the relations between the geometrical arrangements and the characteristics of the distortion, and discussed the conditions which decrease the distortion.
We compared the experimentally reconstructed image from a stereogram with the calculated result, and ascertained that both results agree well.

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In order to examine the deflection of light due to phase objects, the moire fringes generated by superposing the Fourier image of the first grating and the second one in the Talbot interferometer are studied experimentally.
The phase object is placed in front of the first grating.
The light deflected by the object yields the shifted Fourier image, and the resultant moire fringes show the deflection mapping, depending on the distribution of the refractive index of the phase object. The experiments demonstrate the deflection mappings of a piece of flat glass and a candle flame.

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The temporal autocorrelation function of the dynamic speckle intensity detected by a multiple aperture positioned in the Fresnel diffraction field of a diffuse object moving in its own plane under a Gaussian beam illumination is investigated in connection with the translational motion of speckles. The width of the autocorrelation function is related to the correlation distance of speckles and the separation between elementary apertures. The multiple detecting apertures of the two types, in which elementary apertures are distributed in regular and random fashions, are especially taken into consideration and examined in detail by experiments and computer simulation. While the autocorrelation functions of the detected intensity oscillate peculiarly for the regularly distributed multiple apertures, they are found to vary regularly for the randomly distributed multiple apertures if the number of elementary apertures increases. The condition is also quantitatively studied that the speckle intensities detected from different elementary apertures become uncorrelated with each other.

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The light scattering patterns are analyzed for polydispersed nonspherical particles with internal structures, with a view toward the optical studies of bacterial species. When the particles are size-distributed and randomly oriented, the extrema of the scattering pattern are smoothed out, the valid range of Rayleigh-Debye approximation is extended, and the scattering model of complex scatterers can be simplified considerably. The smoothed scattering pattern provides information about average sizes, common shapes and common structures of the scatterers, but it does not clearly provide the information about their refractive indices. Outer and inner structures of bacteria affect the forward and backward scattering respectively. Experimental results with latex spheres and nonspherical bacteria show close agreement with the theoretical calculations based on the scattering pattern analysis presented here.

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Several optical methods are presented to recognize randomly oriented microscopic patterns. By rotating a spatial filter in the Fourier transform plane of the input patterns, the objects of interest are recognized in the output plane, one by one, via correlation spots or reproduced images. Some applications are discussed for the study of microbiological patterns and asbestos fibers.

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