Search NASA⌕ Search

SEARCH · Search NASA

Results for “holography”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6

Two-color holography

Two holograms, made simultaneously, one with a red light component and one with the harmonic UV component to give two fringes in the UV construction due to shortened wavelength. The reconstruction, obtained with a He-Ne laser, could be photographed separately, giving quality interferograms.

Heflinger, L. O.↗

Holography and spacecraft attitude

Holographic device for satellite attitude determination, providing three axis reference information in analog or digital form from single star field sampling

Hallock, J. N.↗

Vibration analysis by time-average holography

Method photographs vibration modes as high as 100 kHz. Technique also measures vibration decay and damping characteristics. Compensation techniques for structural size limitations and for background noise excitations are discussed.

Aprahamian, R.↗

The surface plasmon resonance effect in holography.

A hologram has been made using a surface plasmon resonance wave as the reference beam. The surface wave was stimulated on a 1200-line/mm aluminum reflection grating that was coated with a thin layer of high-resolution photographic emulsion. Experimental results are presented.

Cowan, J. J.↗

Image formation in microwave holography

Microwave holograms are made without offset reference beam, but it has been found that Van der Lugt filter can be used to produce image offset. Also, filter permits "decoding" of holograms in contrast with usual practice of reconstructing visible-light analogs of original micro-wave wave fronts.

Cribbs, R. W.↗

Microwave holography for nondestructive testing

Holographic methods permit use of very large effective apertures so that weak signals can be collected over wide area and integrated to form image. Technique, modification of side-looking radar principle, can be used at very short ranges needed for nondestructive inspection of test specimens.

Cribbs, R. W.↗

Correction of perceived first-order distortions in holography.

Consideration of the problem of distortion posed by a long-wavelength hologram as a three-dimensional display to be viewed by an observer who is included in the distortion problem. The effects of holographic distortion upon the observer's image perception are examined. The inclusion of the visual perception process into the description of holographic imagery necessarily complicates the analysis, but at the same time increases the degrees of freedom by which the image can be altered. It is shown that these additional degrees of freedom make it possible to overcome the problem of unequal longitudinal and lateral magnification.

Winter, D. C.↗

Image enhancement by holography.

The speed of the holographic image deblurring method has recently been further enhanced by a new speed in the realization of the powerful holographic image-deblurring filter. The filter makes it possible to carry out the deblurring, in the optical computer used, in times of the order of one second. The experimental achievements using the holographic image-enhancement method are illustrated with examples ranging from out-of-focus or motion-blurred photographs, including 'amateur' photos recorded on Polaroid film, to the sharpening of the best available electron micrographs of viruses. Images recorded with X-rays, notably from rocket-borne photos of the sun, and out-of-focus photographs from cameras in NASA satellites have been similarly deblurred.

Stroke, G. W.↗