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Fiber-optic fluorescence correlation spectrometer
Applied Optics, 2006Fluorescence correlation spectroscopy (FCS) is a sensitive technique used to probe size, concentration, flow velocity, and reaction kinetics in a dilute solution. Conventional FCS spectrometers achieve this sensitivity at the cost of using bulky optics.
Kanchan, Garai +2 more
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Optical correlator using partial diffusers
Applied Optics, 1980A simple real-time optical correlator based on two contacting correlated partial diffusers is described. The illumination of such diffusers by coherent light produces Young's fringes with the spacing of the fringes determined by the lateral separation of the diffusers.
J F, Young, H M, van Driel
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Optical Correlation Techniques
1974Abstract : The design of a radiometric experiment is described which provides a laboratory model for implementation of the optical correlation technique. The radiometer has provision for alternately viewing the source directly and through a gas absorption cell.
Andrew Tomlinson, Arthur Engelman
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Real-time optical scanning correlator
Applied Optics, 1984A real-time large-capacity rapid-scanning optical correlator utilizing a rotating grating concept is described. We have shown that the proposed optical scanning correlator (OSC) is capable of processing large-capacity optical memories with rapid spectrum scanning.
F T, Yu, X, Lu
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Unconventional optical correlators
SPIE Proceedings, 1990Optical inforriation processing has received much attention since the sixties. The parallel nature of optical systens, their inherently large spacebandwidth product and real-time processing capacity has led to the development of meny syst&me and techniques for opt ical inforntion processing and optical computing.
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, 1974 A survey is given of the most common types of coherent optical correlators, which are classified as spatial plane correlators, frequency plane correlators and special reference correlators. Only the spatial plane correlators are dealt with rather thoroughly.
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Quadratic correlation filters for optical correlators
SPIE Proceedings, 2003Linear correlation filters have been implemented in optical correlators and successfully used for a variety of applications. The output of an optical correlator is usually sensed using a square law device (such as a CCD array) which forces the output to be the squared magnitude of the desired correlation.
Abhijit Mahalanobis +2 more
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Light utilization in optical correlators
Applied Optics, 1982An analysis is made of the overall light efficiency in a coherent optical correlator. The results are applied to a matched filter and an inverse filter. Kogelnik's coupled wave theory is applied to analyze the diffraction efficiency of a filter recorded on a high-efficiency phase medium such as dichromated gelatin.
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Minimum noise and correlation energy optical correlation filter
Applied Optics, 1992A new distortion-invariant optical correlation filter to produce easily detectable correlation peaks in the presence of noise and clutter and to provide better intraclass recognition is presented. The basic ideas of the minimum variance synthetic discriminant function correlation filter (which minimizes noise variance in the output correlation peak ...
G, Ravichandran, D, Casasent
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Optical Correlation Using Diffuse Objectsf
Applied Optics, 1973A technique is discussed whereby one can optically obtain either the autocorrelation or cross-correlation for real, diffuse object arrays using a single lensless Fresnel hologram. The use of diffuse objects yields, with some loss of resolution, an increase in the effective dynamic range of the process. Theoretical analysis of the process indicates that
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