Hsuan Chen

Spatial filtered pseudocolor holographic imaging

A technique of spatial filtered pseudocolor holographic imaging is described. The encoding process takes place at the spatial frequency plane together with the one-step rainbow holographic process. The pseudocolor hologram imaging is obtained by the white light reconstruction of the multiplexed rainbow hologram. This technique provides a simple encoding procedure and offers a wide range of pseudocolor holographic images. The potential applications of this pseudocolor holographic imaging can range from aerial photography for remote sensing to X-ray transparencies for medical diagnosis. Experimental setup of this pseudocolor encoding process is illustrated. Some experimental demonstrations of the pseudocolor encoding hologram images are also provided.

White-light pseudocolor density encoder

A simple technique utilizing a white-light processing system for the pseudocolor encoding of photographic materials by density is presented. Pseudocolored output of many different color codes is obtained by selectively spatial filtering the dispersed colors of the various high-diffraction orders of a halftone input. Besides permitting a large variety of color codes, this white-light technique would also eliminate all coherent artifact noises that plague coherent systems. Experimental results are presented, and comparison with the coherent technique is provided.

One-Step Rainbow Holography: Recent Development And Application

A one-step rainbow holographic process implemented with an imaging lens is presented. The generation of color hologram images by this one-step technique is illustrated. The applications of this one-step technique for the archival storage of color films and the generation of pseudocolor holographic imaging are presented. One of the most interesting and important applications of the one-step process is in holographic interferometry. Demonstrations of double exposure, time averaging, and contour generation by this one-step process are included. As compared with the conventional holographic interferometry, the one-step rainbow holographic process is a very simple and versatile technique which yields the advantages of white light readout. The one-step process offers a brighter image, less speckle noise, and better fringe visibility. For multiwavelength and multislit rainbow holographic interferometry, the techniques enable different physical holographic fringe patterns to be displayed in different colors.

Archival storage of color films by rainbow holographic technique

Abstract A technique of generating color holographic images with a one-step rainbow holographic process is described. This technique offers the capability of archival storage of color materials on a single black and white photographic film. The process is very simple to implement and it allows the reconstruction of the color image with a white light source. Although some degree of color blur is inherent with the rainbow holographic process, it can be minimized by the proper design of the optical system. A simple experimental result is also presented.

Multiwavelength rainbow holographic interferometry

Although the two-step rainbow holographic process of Benton [S. A. Benton, J. Opt. Soc. Am. 50, (1969)] offers a significant improvement in holographic displays, its scientific applications are somewhat limited. It is primarily due to the awkardness of the two-step process. We have demonstrated [H. and F. T. S. Yu, Opt. Lett. 2, 85 (1978)] a one-step process which greatly simplifies the procedure in making rainbow holograms. In this paper, the applications of the one-step process to holographic interferometry is demonstrated. A unique multiwavelength holographic interferometric technique is also introduced. This multiwavelength process enables the study and comparison of more than one physical effect. The holographic interference fringe patterns due to different effects can be displayed individually, or together different colors. This capability further extends the usefulness and versatility of holographic interferometry.

One-Step Rainbow Holographic Interferometry

A one-step rainbow holographic process by using an imaging lens is presented. Results of both the pseudoscopic and orthoscopic rainbow holographic imagings are discussed. One of the most interesting and important applications of the one-step rainbow process is the holographic interferometry. Demonstrations of double exposure, time averaging, and contour generation by this one-step holographic interferometric process are provided. Extension of the one-step process to multiwavelength and multislit holographic interferometry is also included. As compared with the conventional holographic interferometry, the one-step rainbow holograph-ic process is a very simple and versatile technique, which yields the advantages of white light readout. The one-step process offers a brighter image, a lesser speckle noise, and a better fringe visibility. For multi-wavelength and multislit rainbow holographic interferometry, the techniques enable different physical holographic fringe patterns to be displayed in different colors. For multiwavelength technique, they are fringe patterns due to different physical effects, and for multislit technique, they are fringe patterns from different perspectives.