Imation Corporation

William A Challener

William A Tolbert

James M DePuydt

Richard R Ollmann, Jr

An optical assaying method and system having a movable sensor is described. In one aspect, the present invention is a sensing system having a rotating sensor disk coated with indicator dyes sensitized to a variety of substances. In this configuration the sensing system further includes a detector for sensing spectral changes in light received from one or more of the indicator dyes. In another aspect, the present invention is a sensing system having a surface plasmon resonance sensor disk having grooves extending radially from a center of the disk. In yet another aspect, the present invention is a sensing system including a diffraction anomaly sensor disk having a dielectric layer that varies in thickness. The present invention allows for construction of an inexpensive sensing system that is capable of easily detecting a variety of substances either in a sample or a surrounding environment. Furthermore, the present invention provides a sensing system capable of sensing multiple substances without requiring multiple sensors.

Sensor disk having radial grooves and optical assaying method using same

A method and apparatus for optically assaying a targeted substance in a sample using a sensor comprising a dielectric film stack having a plurality of dielectric layers. For at least one angle of incidence the dielectric layers operate as a waveguide for light incident upon the sensor. In one configuration, each dielectric layer comprises a dielectric material selected from a first dielectric material having a first index of refraction and a second dielectric material having a second index of refraction. The dielectric film stack is formed such that the dielectric material of the dielectric layers alternates between the first dielectric material and the second dielectric material. The dielectric film stack is either formed as a dielectric mirror such that light incident upon the sensor reflects from the sensor or as an anti-reflection film stack such that light incident upon the light beam propagates through the sensor. The inventive sensor exhibits a resonance that is comparable in magnitude with resonances commonly exhibited by conventional SPR sensors. However, unlike grating-based SPR sensors, the inventive sensor allows a sample to be assayed with substrate-incident light such that the incident light need not propagate through the sample. In addition, because the sensor does not rely on the use of conductive metals, the sensor enables sharp resonances at shorter wavelengths than conventional SPR sensors.

Optical sensor having dielectric film stack

A method and apparatus for optically assaying a targeted substance in a sample using a diffraction anomaly grating sensor. The optical sensor has a diffraction grating coated with at least one dielectric layer such that the sensor is sensitized to interact with the targeted substance. Upon interaction, light incident upon the sensor at a particular angle propagates through the dielectric, thereby exhibiting a dip in zero-order reflectance. Advantages of the present invention include facilitating increased sensitivity while protecting the metal grating from tarnishing and degradation. The present invention also allows for the construction of sensors that are sensitized to a plurality of substances, thus eliminating the need for an operator to reconfigure the sensing system in order to assay different substances.

Diffraction anomaly sensor having grating coated with protective dielectric layer

Optical assaying method and system having movable sensor with multiple sensing regions

A method and system for optically assaying a substance in a sample using a sensing system having a diffraction grating sensor. A system and method are described that expose the sensor with a light beam at near normal angles of incidence and quantitatively measure the concentration of targeted substance by determining the angular separation between resulting anomaly angles. The present invention also contemplates a system and method that quantitatively measure the concentration of targeted substance by determining the wavelength separation between resulting anomaly wavelengths. Advantages of the present invention include increased sensitivity and less susceptibility to system drifts due to mechanical motion and thermal changes than conventional diffraction grating sensors.

Near normal incidence optical assaying method and system having

Optical assaying method and system having rotatable sensor disk with

A method and apparatus for optically assaying a targeted substance in a sample using a sensor having an optimized groove profile. The optical sensor has a grooved surface defined by a first sinusoidal component superposed with one or more additional sinusoidal components such that a reflectance anomaly occurs at multiple resonance angles. A measure of the targeted substance in the sample can more precisely calculated as a function of a change in angular distance between the resonance angles. Advantages of the present invention include increased sensitivity and less susceptibility to system drifts due to mechanical motion and thermal changes than conventional diffraction grating sensors.

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Grant, MN, United States of America

William A Challener