Results 181 to 190 of about 26,265 (227)

Holographic acoustical lens

The Journal of the Acoustical Society of America, 1978
The theory of an acoustical lens is presented and the construction of such a lens is described. In the present work three experiments are described, in which images of acoustical objects are formed. With the acosutical lens the intermediate step of the conventional acoustical holography of transfering the acoustical hologram to an optical system is ...
C. G. Stephanis, G. D. Hampsas
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Photometrically corrected holographic lens

SPIE Proceedings, 2009
Optical detectors for illumination measurements have the known photopic response V(λ), which is implemented with the help of colored glass filters attached to silicon detectors. In the case of high precision photometry the filter of each detector is hand prepared and the spectral response measured until it is matched to the function V(λ). This method
J. G. Suarez-Romero, R. Salas-Zuñiga
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Use Of A Holographic Lens For Producing Cylindrical Holographic Stereograms

Optical Engineering, 1981
The production of cylindrical holographic stereograms, or multiplex holograms, requires the use of a large, low f/number cylindrical lens to form a line image on the holographic film. To have an image of reasonable size for display purposes, the f/number of the lens must be quite small, on the order of f/1, and the dimensions of the lens must be ...
Richard L. Fusek, Lloyd Huff
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Design and fabrication of transmission phase holographic lens for solar application holographic lens for solar application

2015 2nd International Conference on Opto-Electronics and Applied Optics (IEM OPTRONIX), 2015
Holography has been utilized for fabrication of optical elements in Silver halide photosensitive emulsion. The main drawback of transmission phase holograms in silver halide emulsion is getting darkens or discolor over the period of time, whenexposed to the ambient light, known as print-out effect. Hence this is unsuitable for out-door applications. In
Vadivelan Varadarajan, Chandar Shekar Bellan   +1 more
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Laser Machining with a Holographic Lens

Applied Optics, 1971
A holographic lens is used in conjunction with a pulsed ruby laser for machining single and multiple spots on a 0.12-microm thin film of tantalum deposited on glass. Spot sizes as small as 14 microm have been obtained with hologram diffraction efficiencies as great as 30%.
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Demonstration holograph for comparing an image lens and a real lens

American Journal of Physics, 1977
By making a holograph of a holograph, one can produce a picture in which the virtual image of a lens appears in front of a photographic plate while the images of various objects appear in or behind the plate. This virtual image of the lens has all the properties of an acutal lens when viewing these objects.
Mac Rugheimer, Larry D. Kirkpatrick
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Theory of a Holographic Lens With a High Efficiency

Journal of Optics, 2004
A two element holographic lens is proposed for obtaining high efficiency in a holographic lens. The two element holographic lens is made up of an off-axis holographic lens and a plane holographic grating. The proposed holographic lens can be used for the correction of chromatic aberration in an achromatic doublet. The theory of the holographic lens and
D. V. Udupa, R. P. Shukla, N. C. Das, Murty V. Mantravadi   +3 more
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Holographic projector using one lens

Optics Letters, 2010
It is shown that the lens count in a Fourier holographic projector can be reduced by encoding the equivalent lens power in sets of Fresnel holograms. By using appropriately calculated Fresnel holograms in a reflective configuration to effectively share a lens between the beam-expansion and demagnification stages of a holographic projector, a reduction ...
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Does a Fourier holographic lens exist?

SPIE Proceedings, 1991
A quadratic phase holographic lens can perform Fourier transformation on a two-dimensional input, but the transform is multiplied by a detrimental parasitic phase that is caused by the off-axis configuration. Fortunately, with the proper geometry, and for a limited spatial frequency, this parasitic phase can be considered as a constant, so it need ...
R. Blank, Asher A. Friesem
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Compact lens-less holographic memory

1997 Optical Data Storage Topical Meeting ODS Conference Digest, 2002
A common problem of many holographic memory systems is that they must occupy relatively large areas in order to accommodate the various imaging optics necessary for system operation. A typical memory system requires an imaging lens system between the input and output devices, such as a spatial light modulator (SLM) and charge-coupled device (CCD).
E. Chuang, J.-J. Drolet, G. Barbastathis, D. Psaltis   +3 more
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