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Expert has designed and developed for manufacture linear photodiode array, line-scan CCD and CCD area array-based cameras--either cryogenic or thermoelectric (Peltier) cooled, or uncooled. He helps clients by reviewing their application or existing designs and then recommends optical sensors and electronic designs to meet their performance and cost goals. Acting as a vendor liaison on behalf of clients, he can specify and negotiate custom modifications to standard optical sensors. Expert has designed the camera analog circuits including video preamplifiers, video signal processing chain, sensor clock pulse generators, analog-to-digital conversion, and digital circuits controlling timing and interfacing to microprocessors or host computers. His camera designs have up to 18-bit dynamic range and can detect as few as 10 photons. Expert has designed with image intensifier tubes, serving as either high-speed optical shutters to control exposure time or as high-gain light amplifiers. He is also familiar with mechanical camera shutter design. Camera photoresponses cover the visible spectrum and extend into the ultraviolet and near infrared. Some of Expert's imaging applications include machine vision or inspection, law enforcement, forensics, medical diagnostic, photography, remote sensing, night vision, and spectroscopy.


Expert has designed analog circuits in the frequency range of DC to 360 MHz with input/output capabilities ranging from microvolts and picoamps to amps. He designs front-end signal preamplifiers with discrete components to amplify sensor or detector voltage; current or charge signals; broadband analog signal chains exhibiting good DC performance; high-speed, high-resolution analog-to-digital (A/D) conversion circuits; regulated switched-mode high voltage power supply circuits, under 10 watts, having outputs up to 20 kilovolts; and linear direct current (DC) power supplies up to 200 watts.

Many of Expert's electronic instrument designs measure analog signals and provide digital outputs of the measured quantities. These systems make high-speed or high-resolution measurements. He has designed circuits employing commercially available A/D converters ranging from high-speed flash to medium-speed, high-resolution converters. Expert has a patent (5198816) that describes a new A/D conversion technique as well as circuits used in a currently manufactured light measuring instrument. As implemented, that A/D converter has 18 bits of dynamic range and 10 microsecond conversion time.

Expert has designed and developed light measuring and imaging equipment employing optical sensing charge-coupled devices. He has experience applying front- and back-side illuminated, multi-phase pinned (MPP), frame transfer, interline transfer, and charge injection device types of linear or line-scan, and area array or 2D, CCD optical sensors to his designs. He has direct experience with the standard products of US and overseas manufactures and can act as a vendor liaison on behalf of clients to specify and negotiate custom design modifications. He also designs and develops electronic circuits to support those sensors in applications.


Another of Expert's areas of expertise involves the design and development for manufacture of solid-state high voltage pulse generators. These generators have an output of up to 350 volt peak pulses with rise and fall times faster than 2.5 nanoseconds, have fixed or adjustable pulse widths ranging from less that 5 nanoseconds to DC, and pulse repetition rates up to 1 MHz. Alternatively, some can be configured to provide current pulses of up to several amps and some are based on avalanche transistor techniques.


Expert has experience using tubes of various sizes, photocathode formulations, and dynode configurations and has designed and developed for manufacture low-light-level and photon counting instrumentation employing photomultiplier tubes (PMTs). He designs precision regulated switched-mode high voltage power supplies to bias the tube dynode string, low-noise current pulse amplifier-discriminators to provide ECL-, TTL-, and NIM-compatible output pulses for photon counting, and current-to-voltage converting preamplifiers for scanning and high-dynamic range applications.


In the area of night-vision technology, Expert has worked with generation 1.5, 2, and 3 type wafer tubes with single, dual-chevron, triple-Z and high-linearity hot microchannel plates; various photocathode types covering the X-ray, ultraviolet, visible, and infrared portions of the spectrum; and various phosphor types. His experience with the standard products of US and overseas manufacturers enables him to act as a vendor liaison to specify and negotiate custom modifications. He also designs electronic circuits to support image intensifier applications including switched-mode high-voltage power supplies, high-voltage pulse and impulse generators for gating or shuttering, and related digital control circuitry.


Expert has designed and developed electronic circuits for light measuring and imaging equipment using linear and area photodiode arrays. His experience with the standard products of US and overseas manufacturers enables him to act as a vendor liaison to specify and negotiate custom photodiode modifications.


Expert has designed front-end sensor signal-preamplifiers from discrete components such as transistors, field effect transistors, and operational amplifiers (opamps). His designs range from low-noise voltage, current, and charge types--high and low input impedance. Their operational bandwidth falls within the DC to 360 MHz region.


Expert has designed and developed Peltier cooler subsystems used with optical sensors and related components. These systems utilize off-the-shelf and custom configured plates and range from single to multi-stage assemblies and employ ambient air, forced-air, or liquid heat exchange medium for waste heat removal. He also designs temperature regulation circuits and thermoelectric cooler power supplies.