The production of holograms by a single axial mode ruby laser

Thesis (M.S.)--University of Rochester. College of Engineering and Applied Science. Institute of Optics, 1967. Appendix, "High intensity reciprocity failure in Kodak 649-F plates at 6934A," co-authored by Michael Hercher.A ruby laser, operating in a single axial mode, has been successfully used to obtain holograms by the wavefront reconstruction process. The narrow spectral bandwidth of the laser emission, which single mode operation implies, has permitted holograms to be produced in an experimental arrangement having a 50 cm path difference between the two interfering beams. Two experimental results indicate that the single axial mode ruby laser operating in the conventional pulsed configuration is better suited to the production of holograms of stationary objects than is the laser operated in the Q-switched configuration. First, holograms of comparable quality were produced by the laser operating in both configurations. Secondly, severe high intensity reciprocity failure was detected in the Kodak 649-F Spectroscopic Plates which were used to record the holograms. This effect, which was present in plates exposed by emission from the laser in both configurations, was far more pronounced in exposures made by the extremely short pulse-width radiation from the Q-switched laser. Moreover, vibration of the apparatus used in making a hologram has not restricted the production of holograms of stationary objects with the laser in the conventional pulsed configuration. An analytic technique for estimating the effects of equipment motion during a holographic exposure was developed in this study, but it was not tested. The quality of images reconstructed from holograms produced in this study was limited by interference effects in the diffuse coherent radiation used to illuminate the object, and by wavefront aberrations. These aberrations were due to the fact that the reference beam used in obtaining the holograms, and the reconstructing beam used to view the holographic images, differed both in wavelength and transverse structure. Holographic techniques were found to be very useful in investigating the transverse, or angular nature of the ruby laser emission. Preliminary attempts at producing holograms of diffusely reflecting subjects were only marginally successful. Additional efforts in this area should bring better results