Abstract: Super-resolution time delay and integrate (TDI) imaging processing and systems for providing same utilize imaging geometry configured such that a predictable sub-pixel component of the frame-to-frame image motion can be used to construct a high-resolution output image from multiple under-sampled low-resolution input images.

Abstract: Imaging devices and techniques that utilize multiple optical detectors are described and, in particular, imaging geometries for imaging devices that include three or more optical detectors with overlapping fields of regard. The imaging geometries are determined and provided in consideration of one or more performance criteria evaluated over multiple different operating conditions for a process of generating a reconstructed image from the captured images. Imaging systems and methods utilizing the imaging geometries are also described.

Abstract: Methods and systems for estimating peak location on a sampled surface (e.g., a correlation surface generated from pixilated images) utilize one or more processing techniques to determine multiple peak location estimates for at least one sampled data set at a resolution smaller than the spacing of the data elements. Estimates selected from the multiple peak location estimates are combined (e.g., a group of estimates is combined by determining a weighted average of the estimates selected for the group) to provide one or more refined estimates. In example embodiments, multiple refined estimates are combined to provide an estimate of overall displacement (e.g., of an image or other sampled data representation of an object).

Abstract: Imaging devices and techniques that utilize multiple optical detectors are described and, in particular, imaging geometries for imaging devices that include three or more optical detectors with overlapping fields of regard. The imaging geometries are determined and provided in consideration of one or more performance criteria evaluated over multiple different operating conditions for a process of generating a reconstructed image from the captured images. Imaging systems and methods utilizing the imaging geometries are also described.

Abstract: Methods and systems for estimating peak location on a sampled surface (e.g., a correlation surface generated from pixilated images) utilize one or more processing techniques to determine multiple peak location estimates for at least one sampled data set at a resolution smaller than the spacing of the data elements. Estimates selected from the multiple peak location estimates are combined (e.g., a group of estimates is combined by determining a weighted average of the estimates selected for the group) to provide one or more refined estimates. In example embodiments, multiple refined estimates are combined to provide an estimate of overall displacement (e.g., of an image or other sampled data representation of an object).

Abstract: Super-resolution time delay and integrate (TDI) imaging processing and systems for providing same utilize imaging geometry configured such that a predictable sub-pixel component of the frame-to-frame image motion can be used to construct a high-resolution output image from multiple under-sampled low-resolution input images.

Abstract: In a binary joint transform correlator, a Fourier plane binarization threshold is provided which alternates between even and odd rows and reduces noise in the output plane and improves discrimination between matched and unmatched prints. Periodically correlating with a known standard input and normalizing the output peak intensity prevents correlator performance drift from degrading fingerprint recognition performance. Experimental system performance is assessed statistically, in terms of the false pass rate seen when operating with a constant false alarm rate. By applying both techniques, a false pass improvement from 6.95% to 0.076% is experimentally demonstrated at a false alarm rate of 0.1 percent.

Abstract: A lensless joint transform correlator optically determines the relative position of two pinholes placed in parallel arms of a Mach-Zehnder interferometer. The Fraunhaufer diffraction patterns combine to form a joint power spectrum signal in the joint transform plane. Because of the interference of the two pinhole signals, an encoded lens comprising a Fresnel zone is formed in the joint Fraunhaufer diffraction pattern which is illuminated with a plane wave, and the output signal is taken in the focal plane of the Fresnel zone and magnifies the input pinhole displacement by a factor of ten, enhancing its use in precision positioning servo systems for mask alignment.

Abstract: An amplitude encoded lens function signal, similar to a zone plate, is formed in the transform plane of a chirp encoded joint transform correlator. CCD correlation spot light sensor is separated from the transform plane by the focal length of the encoded lens function, and generates the desired output correlation spot. As a result, no prior art inverse transform lens need be provided, which simplifies the design. Further simplification is attainable in a low noise commercial image matching environment by eliminating the CCD correlation spot sensor entirely, and verifying an input image/reference image close match by using the eye of an operator to check for the presence of the visible zone plate, indicative of such a match.

Abstract: A joint transform correlator has modulators for temporally modulating a first optical input signal at a first frequency and a second optical input signal at a second frequency. An image sensor in the Fourier plane forms a product signal modulated by temporal sum and difference frequencies of the first and second frequencies. The product signal is thereafter demodulated at the temporal sum or difference frequency and the resulting optical signal is inverse Fourier transformed to recover the desired cross correlation signals.

Abstract: The rapidly moving uniform surface being inspected is illuminated with either laser or wide-band light. The Fourier transform of the surface is produced upon the detector plane of an electronic camera. In the absence of defects, the transform light energy is produced only in the center of the detector plane but in the presence of defects light is produced in various non-centralized portions of the detector plane which can indicate the orientation and size of the defect.