Abstract: A method for improving the performance of an image sensor array includes performing an electrical test on the image sensor array, generating a test image from the electrical test to detect an open circuit in a data line of the image sensor array, performing a laser-weld operation the data line to weld a portion of the data line to ground, re-testing the image sensor array to confirm a successful laser-weld operation, performing a laser-cut on a readout portion of the data line, and re-testing the image sensor array to confirm a successful laser-cut operation.

Abstract: A method for improving the performance of an image sensor array includes performing an electrical test on the image sensor array, generating a test image from the electrical test to detect an open circuit in a data line of the image sensor array, performing a laser-weld operation the data line to weld a portion of the data line to ground, re-testing the image sensor array to confirm a successful laser-weld operation, performing a laser-cut on a readout portion of the data line, and re-testing the image sensor array to confirm a successful laser-cut operation.

Abstract: A mask for use in making a planar PN junction in a semiconductor device includes a central mask opening and a plurality of spaced apart concentric mask openings surrounding the central mask opening. The concentric mask openings each have a width less than a maximum dimension of the central mask opening. The central mask opening can be circular and the concentric mask openings can have a ring-shape. The mask can be used to form openings in a wafer layer for introducing an impurity to dope that wafer layer.

Abstract: A method and apparatus for providing non-linear, passive quenching of avalanche currents in Geiger-mode avalanche photodiodes (APDs) is provided. A non-linear, passive, current-limiting device is connected in series with the APD and a bias source. The non-linear, passive, current-limiting device rapidly quenches avalanche currents generated by the APD in response to an input photon and resets the APD for detecting additional photons, using a minimal number of components. The non-linear, passive, current-limiting device could comprise a field-effect transistor (FET), as well as a junction FET (JFET) a metal-oxide semiconductor FET (MOSFET), or a current-limiting diode (CLD) connected in series with the APD and the bias source.

Abstract: Methods for detecting the presence or absence of ice or liquid water on surfaces are provided. In a first embodiment of the invention, a reflectance spectrum from a surface to be tested is measured using any suitable near-infrared optical system. The midpoint wavelength of the transition or step of the measured reflectance spectrum near 1.4 microns is calculated, and compared to a decision threshold wavelength. If the midpoint wavelength is less than the decision threshold wavelength, the presence of liquid water on the surface is indicated. If the midpoint wavelength is greater than the decision threshold wavelength, the presence of ice is indicated on the surface. In a second embodiment of the invention, at least three reflectance levels are measured at three wavelengths, and a dimensionless decision function is applied to the measured reflectance levels. Output of the decision function is compared to at least two pre-defined ranges.