Characteristics and measurements of an aperture-limited in-line hologram image.

The intensity distribution in the neighborhood of the real image reconstructed from an in-line Fraunhofer hologram was investigated. Assuming a finite amount of information recorded on the hologram in terms of a limiting aperture, the image is shown to possess intensity variations that are dependent on the argument of a first-order Bessel function recorded on the hologram. The theoretical results are presented on isophote diagrams and are verified experimentally. Three measurements of the image width are presented, and the inherent errors are found. The focal tolerance of the aperture-limited image relative to the recording parameters is discussed.

Holographic techniques for the study of dynamic particle fields.

The techniques of small particle holography are extended in an elementary way to show that multiple exposure holography can be used to study the dynamic properties of particle fields. Experimental techniques for performing such a study are then described. Finally, as a typical example, a multiple exposure hologram of an aerosol is presented with a portion of the data extracted from it. The hologram exhibits a vast amount of information including the determination of the velocity and density field, size distribution, flow structure, and diffusion rate.