University of California

The United States of America As Represented by the United States

The United States of America As Represented by the Department of Energy

Joseph R Kimbrough

Joseph W Balch

Nicholas J Colella

Laurence R Brewer

James Courtney Davidson

J Courtney Davidson

A system and method is disclosed for chromatography and electrophoresis using circular optical scanning. One or more rectangular microchannel plates or radial microchannel plates has a set of analysis channels for insertion of molecular samples. One or more scanning devices repeatedly pass over the analysis channels in one direction at a predetermined rotational velocity and with a predetermined rotational radius. The rotational radius may be dynamically varied so as to monitor the molecular sample at various positions along a analysis channel. Sample loading robots may also be used to input molecular samples into the analysis channels. Radial microchannel plates are built from a substrate whose analysis channels are disposed at a non-parallel angle with respect to each other. A first step in the method accesses either a rectangular or radial microchannel plate, having a set of analysis channels, and second step passes a scanning device repeatedly in one direction over the analysis channels. As a third step, the scanning device is passed over the analysis channels at dynamically varying distances from a centerpoint of the scanning device. As a fourth step, molecular samples are loaded into the analysis channels with a robot.

System and method for chromatography and electrophoresis using circular optical scanning

A system and method is disclosed for optically locating a microchannel position. A laser source generates a primary laser beam which is directed at a microchannel plate. The microchannel plates include microchannels at various locations. A back-reflectance beam detector receives a back-reflected beam from the plate. The back-reflected beam is generated when the primary beam reflects off of the plate. A photodiode circuit generates a trigger signal when the back-reflected beam exceeds a predetermined threshold, indicating a presence of the microchannel. The method of the present invention includes the steps of generating a primary beam, directing the primary beam to a plate containing a microchannel, receiving from the plate a back-reflected beam generated in response to the primary beam, and generating a trigger signal when the back-reflected beam exceeds a predetermined threshold which corresponds to a presence of the microchannel.

System and method for optically locating microchannel positions

A 'blink' technique, analogous to a person blinking at a flash of bright light, is provided for mitigating the effects of single event current latchup and prompt pulse destructive radiation on a micro-electronic circuit. The system includes event detection circuitry, power dump logic circuitry, and energy limiting measures with autonomous recovery. The event detection circuitry includes ionizing radiation pulse detection means for detecting a pulse of ionizing radiation and for providing at an output terminal thereof a detection signal indicative of the detection of a pulse of ionizing radiation. The current sensing circuitry is coupled to the power bus for determining an occurrence of excess current through the power bus caused by ionizing radiation or by ion-induced destructive latchup of a semiconductor device. The power dump circuitry includes power dump logic circuitry having a first input terminal connected to the output terminal of the ionizing radiation pulse detection circuitry and having a second input terminal connected to the output terminal of the current sensing circuitry. The power dump logic circuitry provides an output signal to the input terminal of the circuitry for opening the power bus and the circuitry for shorting the power bus to a ground potential to remove power from the power bus. The energy limiting circuitry with autonomous recovery includes circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential. The circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential includes a series FET and a shunt FET. The invention provides for self-contained sensing for latchup, first removal of power to protect latched components, and autonomous recovery to enable transparent operation of other system elements.

System level latchup mitigation for single event and transient radiation

A barrier at a uniform depth for an entire wafer is used to produce imaging devices less susceptible to noise pulses produced by the passage of ionizing radiation. The barrier prevents charge created in the bulk silicon of a CCD detector or a semiconductor logic or memory device from entering the collection volume of each pixel in the imaging device. The charge barrier is a physical barrier, a potential barrier, or a combination of both. The physical barrier is formed by an SiO.sub.2 insulator. The potential barrier is formed by increasing the concentration of majority carriers (holes) to combine with the electron's generated by the ionizing radiation. A manufacturer of CCD imaging devices can produce radiation-tolerant devices by merely changing the wafer type fed into his process stream from a standard wafer to one possessing a barrier beneath its surface, thus introducing a very small added cost to his production cost. An effective barrier type is an SiO.sub.2 layer.

Growing community of inventors

Pleasanton, CA, United States of America

Joseph R Kimbrough