Photonics Dictionary

A superposition of many zone plates, each reconstructing a real and virtual point image at the appropriate locations upon illumination by a reference beam.

Coded image obtained optically with a nonredundant pinhole array imaging aperture.

Essentially, a hologram of a hologram, in which the first-generation hologram is masked with a narrow slit. During image reconstruction, the slit operates as the exit pupil in image space. The...

An image that appears when a hologram is illuminated by a suitable light source, generally a laser beam.

The coherent wave used to play back a recorded hologram. It is identical to the reference wave used in the generation of the original hologram; part of it is diffracted by the recording medium and...

In holography, the beam of light that is directed from the beamsplitter to the recording medium, where it interferes with the object beam to generate the hologram.

A hologram that is illuminated by a source from the viewer's side.

A disc composed of a series of holographic optical elements that diffract light at various angles. When spinning, a raster scan may be generated.

The superimposing of holographic pages in a thick, erasable storage material by changing the reference and object beams. This extends the capacity of holographic memories.

A term referring to the pre-exposed hologram of the subject used in holographic interferometry.

An imaging technique in which an object moving through an interference field formed in space scatters light and is spatially recorded on a photographic film as a hologram. If the interference field...

A technique used to suppress extreme noise amplification during digital image reconstruction that relies on smoothing and differentiation of the data by simplified least squared procedures.

A two-dimensional hologram.

Multiple exposures of holograms, one for each position of a vibrating image, that are used for vibration analysis and that yield a record of the time-averaged irradiance distribution at the hologram...

A hologram that is illuminated by a source opposite the viewer.

Illumination of hologram facets with a beam that covers only a small portion of the hologram in order to optimize laser energy use. See overillumination.

Short-distance scattering of light in holography caused by random index inhomogeneities and the developing index that interferes with the incident beam, thus recording a hologram of the scattered...

A three-dimensional hologram.

The theorem stating that, when the sampling period in a recorded sample hologram is matched to the object spectrum, the resulting image does not suffer any loss of information content.