System and Method of Compensating for System Delay in Analyte Analyzation

• US 20080044922A1
• Filed: 08/13/2007
• Published: 02/21/2008
• Est. Priority Date: 08/18/2006
• Status: Active Grant

• Current Assignee: RIC INVESTMENTS LLC (Respironics Incorporated)
• Original Assignee: RIC INVESTMENTS LLC (Respironics Incorporated)
• Inventors: Mueller, Cord
• Granted Patent: US 7,781,221 B2
• Time in Patent Office: Days
• US Class Current: 436/127
• CPC Class Codes: A61B 5/0833 Measuring rate of oxygen consumption
• CPC Class Codes: A61B 5/097 Devices for facilitating collection of breath or for directing breath into or through measuring devices
• CPC Class Codes: G01N 21/6408 with measurement of decay time, time resolved fluorescence
• CPC Class Codes: Y10T 436/20 Oxygen containing

Abstract

A system configured to determine information related to one or more gaseous analytes in a body of gas comprises a luminescable material, one or more emitters, one or more photosensitive detectors, and a processor. The emitters emit amplitude modulated electromagnetic radiation onto the luminescable medium in communication with a body of gas causing luminescence in the luminescable medium. The photosensitive detectors receive the amplitude modulated electromagnetic radiation generated by the luminescence of the luminescable medium and generate one or more output signals, at least one of the output signals indicating the intensity of the received electromagnetic radiation. The processor receives the output signals and determines information related to one or more gaseous analytes in the body of gas. The determination of information related to the one or more gaseous analytes may comprise compensating for a delay that varies as a function of the intensity of the received electromagnetic radiation.

Claims

1. A system configured to determine information related to one or more gaseous analytes in a body of gas, the system comprising:

a luminescable medium in communication with a body of gas;

one or more emitters configured to emit amplitude modulated electromagnetic radiation onto the luminescable medium, wherein the emitted amplitude modulated electromagnetic radiation causes luminescence in the luminescable medium;

a photosensitive detector configured to receive amplitude modulated electromagnetic radiation that is generated by luminescence of the luminescable medium, wherein the photosensitive detector generates one or more output signals in response to the received amplitude modulated electromagnetic radiation, the output signals indicating an intensity of the received amplitude modulated electromagnetic radiation; and

a processor adapted to receive the one or more output signals generated by the photosensitive detector and adapted to determine information related to one or more gaseous analytes in the body of gas based on a phase difference between a modulation of the amplitude of the emitted amplitude modulated electromagnetic radiation and a modulation of the amplitude of the received amplitude modulated electromagnetic radiation,

wherein the processor is adapted to compensate for a delay, by the photosensitive detector in the generation of the one or more output signals, while determining the information related to the one or more gaseous analytes the compensation varying as a function of the intensity of the received amplitude modulated electromagnetic radiation.

2. The system of claim 1, wherein the one or more gaseous analytes comprises oxygen.

3. The system of claim 1, wherein the information related to the one or more gaseous analytes comprises concentrations of the one or more gaseous analytes in the body of gas.

4. The system of claim 1, wherein the processor comprises a phase difference module adapted to determine the phase difference between the modulation of the amplitude of the emitted amplitude modulated electromagnetic radiation and the modulation of the amplitude of the received amplitude modulated electromagnetic radiation.

5. The system of claim 4, wherein the phase difference module comprises a lock-in amplifier.

6. The system of claim 4, wherein the processor is adapted to (i) determine the delay of the photosensitive detector in the generation of the one or more output signals based on the intensity of the received amplitude modulated electromagnetic radiation as indicated by the one or more output signals, and (ii) compensate, based on the determined delay, for the delay of the photosensitive detector in the generation of the one or more output signals by adjusting the phase difference determined by the phase difference module.

7. The system of claim 1, wherein the processor is adapted to control the one or more emitters.

8. A method of determining information related to one or more gaseous analytes in a body of gas, the method comprising:

providing an emitted amplitude modulated electromagnetic radiation onto a luminescable medium in communication with a body of gas so as to cause luminescence in the luminescable medium;

receiving an amplitude modulated electromagnetic radiation, wherein the received amplitude modulated electromagnetic radiation is generated by the luminescence of the luminescable medium;

generating one or more output signals indicating an intensity of the received amplitude modulated electromagnetic radiation received from the luminescable medium;

determining information related to one or more gaseous analytes in the body of gas based on a phase difference between a modulation of the amplitude of the emitted amplitude modulated electromagnetic radiation and a modulation of the amplitude of the received amplitude modulated electromagnetic radiation; and

providing a compensation for a delay between the receipt of the received amplitude modulated electromagnetic radiation and generation of the one or more output signals, the compensation varying as a function of the intensity of the received amplitude modulated electromagnetic radiation.

9. The method of claim 8, wherein the one or more gaseous analytes comprises oxygen.

10. The method of claim 8, wherein determining information related to the one or more gaseous analytes comprises determining concentrations of the one or more gaseous analytes in the body of gas.

11. The method of claim 8, wherein determining information related to the one or more gaseous analytes further comprises determining the phase difference between the modulation of the amplitude of the emitted amplitude modulated electromagnetic radiation and the modulation of the amplitude of the received amplitude modulated electromagnetic radiation.

12. The method of claim 11, wherein determining information related to the one or more gaseous analytes further comprises (i) determining the delay between receipt of the received amplitude modulated electromagnetic radiation and the generation of the one or more output signals indicating the intensity of the received amplitude modulated electromagnetic radiation, and (ii) providing the compensation for the delay by adjusting, based on the determined delay, the determined phase difference between the modulation of the amplitude of the emitted amplitude modulated electromagnetic radiation and the modulation of the amplitude of the received amplitude modulated electromagnetic radiation.

13. The method of claim 8, further comprising emitting the emitted amplitude modulated electromagnetic radiation.

14. A processor configured to determine information related to one or more gaseous analytes in a body of gas, the processor comprising:

a phase difference module adapted to determine a phase difference between (i) a modulation of the amplitude of an emitted amplitude modulated electromagnetic radiation that has been provided to a luminescable medium in communication with a body of gas and (ii) a modulation of the amplitude of a received electromagnetic radiation generated by luminescence of the luminescable medium in response to the emitted amplitude modulated electromagnetic radiation provided thereon,

wherein the phase difference module is adapted to determine the phase difference based on one or more output signals generated by a photosensitive detector, wherein the photosensitive detector is structured to receive at least a portion of the received amplitude modulated electromagnetic radiation generated by the luminescence of the luminescable medium and structured to generate the one or more output signals, and wherein at least some of the output signals indicate at least the intensity of the received amplitude modulated electromagnetic radiation generated by the luminescence of the luminescable medium;

a delay compensation module adapted to provide a compensation for a delay of the photosensitive detector in generating the one or more output signals, wherein the compensation varies as a function of the intensity of the received amplitude modulated electromagnetic radiation generated by the luminescence of the luminescable medium; and

an analyte information module adapted to determine information related to one or more gaseous analytes in the body of gas based on the phase difference.

15. The processor of claim 14, wherein the one or more gaseous analytes comprises oxygen.

16. The processor of claim 14, wherein the information related to the one or more gaseous analytes determined by the processor comprises concentrations of the one or more gaseous analytes in the body of gas.

17. The processor of claim 14, wherein the phase difference module comprises a lock-in amplifier.

18. The processor of claim 14, wherein the delay compensation module is further adapted to (i) determine the delay of the photosensitive detector in the generation of the one or more output signals based on the intensity of the received amplitude modulated electromagnetic radiation, wherein the intensity is indicated by the one or more output signals, and (ii) compensate for the delay of the photosensitive detector in the generation of the one or more output signals by adjusting the phase difference determined by the phase difference module based on the determined delay.

19. The processor of claim 14, wherein the delay compensation module is further adapted to (i) determine the delay of the photosensitive detector in the generation of the one or more output signals based on the intensity of the received amplitude modulated electromagnetic radiation, wherein the intensity is indicated by the one or more output signals, and (ii) compensate for the delay of the photosensitive detector in the generation of the one or more output signals by adjusting the one or more output signals to account for the delay, and wherein the phase difference module is further adapted to determine the phase difference based on the output signals that have been adjusted by the delay compensation module.

20. A method of determining information on a gaseous analyte in a body of gas, comprising:

determining a phase difference between (i) a modulation of the amplitude of an emitted amplitude modulated electromagnetic radiation provided to a luminescable medium in communication with a body of gas and (ii) a modulation of the amplitude of a received amplitude modulated electromagnetic radiation generated by the luminescence of the luminescable medium,

wherein the phase difference is determined, at least in part, based on output signals generated as a function of the intensity of the received amplitude modulated electromagnetic radiation generated by the luminescence of the luminescable medium;

compensating for a delay in generation of the output signals as a function of the intensity of the received amplitude modulated electromagnetic radiation generated by the luminescence of the luminescable medium; and

determining information related to the gaseous analyte based upon the determining and the compensating.