Abstract: A vector impedance measurement system (100) includes a first radio frequency (RF) source (101) for providing energy to a test circuit. A measurement device (111) is used for providing a first network measurement based upon the voltage and current at the terminals of the test circuit. A second RF source (103) is used for down converting the first network measurement to a second network measurement that is lower in frequency. The vector impedance system (100) operates to calculate a complex impedance using both the magnitude and phase angle of the second network measurement as determined by a processor (133). In that the lower frequency at which signal processing is performed is a fixed frequency, many sensitive parameters of the band pass filters, such as gain and phase shift, can be easily calibrated and do not change during operation, resulting in a simpler calibration process and very accurate data measurements.

Abstract: A vector impedance measurement system (100) includes a first radio frequency (RF) source (101) for providing energy to a test circuit. A measurement device (111) is used for providing a first network measurement based upon the voltage and current at the terminals of the test circuit. A second RF source (103) is used for down converting the first network measurement to a second network measurement that is lower in frequency. The vector impedance system (100) operates to calculate a complex impedance using both the magnitude and phase angle of the second network measurement are determined by a processor (133). In that the lower frequency at which signal processing is performed is a fixed frequency, many sensitive parameters of the band pass filters, such as gain and phase shift, can be easily calibrated and do not chance during operation, resulting in a simpler calibration process and very accurate data measurements.

Abstract: An inspection system utilizes an image doubler design that includes a plurality of mirrors that effectively folds the object distance by reflecting the image along a folded path. Strobed illumination is used in conjunction with a shutterless camera. Increased image resolution results from an optional anamorphic lens with vertical magnification. The lens assembly includes concentric toroidal lens that are produced from a single piece of machineable optical material.

Abstract: An apparatus and method for locating a pattern within a digital representation of an image. A video camera scans an image of light reflected from the surface of an object. The analog output of the video camera is digitized to form the digital representation. In order to digitize the analog output a threshold signal is provided. A comparator receives both the threshold signal and the analog output. When the difference between the threshold signal and analog exceeds a certain value the comparator changes its output from one digital level to another until the difference is less than the certain value. The threshold signal is produced by an adaptive threshold circuit which integrates the analog output over one scan of the image to form an integrated signal. This integrated signal is the normalized and stored into a sample and hold circuit for use in a subsequent scan as the threshold signal.