Optical fiber distribution system for an optical fiber sensor in a luminescent sensor system

• US 5,311,013 A
• Filed: 10/15/1992
• Issued: 05/10/1994
• Est. Priority Date: 10/15/1992
• Status: Expired due to Fees

• Current Assignee: Abbott Laboratories Incorporated
• Original Assignee: Abbott Laboratories Incorporated
• Inventors: Lindberg, John M., Gutcheck, Robert A., Vurek, Gerald G.
• Primary Examiner(s): Messinger, Michael
• Application Number:
  US07/961,559
• Time in Patent Office: 572 Days
• Field of Search: 250/227.23, 250/226, 250/227.21, 356/39-41, 385/12, 128/633, 128/634
• US Class Current: 250/227.23
• CPC Class Codes: G01D 5/268 using optical fibres G01D5/28 - G01D5/38 take precedence
• CPC Class Codes: G01N 2021/772 Tip coated light guide
• CPC Class Codes: G01N 2021/7786 Fluorescence
• CPC Class Codes: G01N 21/7703 using reagent-clad optical fibres or optical waveguides using measurement of total internal reflection or attenuated total reflection G01N21/552; optical fibres or waveguides per se G02B
• CPC Class Codes: G01N 2201/062 LED's
• CPC Class Codes: G02B 6/4202 for coupling an active element with fibres without intermediate optical elements, e.g. fibres with plane ends, fibres with shaped ends, bundles
• CPC Class Codes: G02B 6/4204 the coupling comprising intermediate optical elements, e.g. lenses, holograms encapsulated active devices H01S5/02208, H01L33/52
• CPC Class Codes: H01S 5/02415 by using a thermo-electric cooler [TEC], e.g. Peltier element

Abstract

An optical distribution system incorporating an improved luminescent based optical fiber sensor incorporating a signal generating component for generating a first optical signal, a signal separating component for delivering said first optical signal to the sensor, delivering said second returned optical signal to an associated signal detector, and including signal interference means to separate said first and second signals and minimize cross-talk therebetween. A sensor optical fiber connects a sensor tip to the signal separating component. The signal detector receives a returned signal from the signal separating component and transmits it to a signal-measuring component of the distribution system.

Claims

1. A distribution system for a sensor that utilizes an analyte-sensitive indicator module to monitor the concentration of an analyte, the sensor having:

a temperature stabilized signal generating component for generating a first optical signal of a precise first wavelength, an indicator molecule for producing a second returned optical signal of a precise second wavelength, the first signal wavelength being such that the intensity and temporal behavior of the signal is predictably altered by the indicator molecule so that the wavelength temporal behavior of the returned signal is predictable;

a single-fiber sensor tip that includes the indicator molecule; and

a signal-measuring compound for receiving signals from the distribution system, the distribution system comprising;

a temperature stabilized, signal generating component for generating said first optical signal of a precise first wavelength;

a signal detector;

a signal separating component for delivering said first optical signal of a precise first wavelength to the sensor, delivering said second returned optical signal of a precise second wavelength to said signal detector, and including signal interference means to separate said first and second signals and minimize cross-talk therebetween;

at least one discrete spectral interference microfilter for eliminating side bands of the wavelength of the second returned optical signal from the first optical signal and at least another discrete spectral interference microfilter for eliminating the wavelength of the first optical signal from the second returned optical signal to the signal detector; and

a sensor optical fiber for connecting a sensor tip to the signal separating component to transmit said first optical signal to the sensor tip, and to return the resulting indicator signal from the sensor tip to the signal separating component, said

signal detector receiving said second returned signal from the signal separating component and transmitting it to the signal-measuring component, the signal output is substantially smaller than the signal input and whereby the intensity of said first signal is maximized such that the intensity of the indicator signal of a wavelength corresponding to the wavelength of the signal received by the signal-measuring component is suitable for monitoring the signal input to the distribution system.

2. A distribution system for a sensor as claimed in claim 1 wherein the temperature stabilized signal generating component comprises an LED assembly for generating said first optical signal of a precise first wavelength.

3. A distribution system for a sensor as claimed in claim 1 wherein the temperature stabilized signal generating component comprises a laser for generating said first optical signal of a precise first wavelength.

4. A distribution system for a sensor as claimed in claim 1 wherein the signal separating component comprises a wavelength division multiplexer including a first signal separator element and a second signal separator element, with light returning from the sensor fiber first striking the first signal separator element which reflects the first signal onto a first fiber end associated with the signal indicating component, with the light that is not reflected off of the first signal separator element traveling to the second signal separator element and is reflected onto a second fiber end associated with the signal detector, thus separating the components of incoming multi-colored light and directing each component to a respective filter.

5. A distribution system for a sensor as claimed in claim 1 wherein the signal detector for receiving said second returned optical signal comprises an avalanche photo diode (APD).

6. A distribution system for a sensor as claimed in claim 1 wherein the signal detector for receiving said second returned optical signal comprises a p*material-intrinsic material-n*material (PIN) device.

7. An improved modular optical sensor for decoding phosphorescent base sensor signals where the signal output is substantially smaller than the signal input, said sensor comprising:

a temperature stabilized signal generating component for generating a first optical signal of a precise first wavelength;

an indicator molecule for producing a second returned signal of a precise second wavelength;

the first signal wavelength being such that the intensity and temporal behavior of the signal is predictably altered by the indicator molecule so that the wavelength temporal behavior of the returned signal is predictable;

a single-fiber sensor tip that includes the indicator molecule;

a signal detector;

a signal separating component for delivering said first optical signal of a precise first wavelength to the sensor, delivering said second returned optical signal of a precise second wavelength to said signal detector, and including signal interference means to separate said first and second signals and minimize cross-talk therebetween; and

at least one discrete spectral interference microfilter for eliminating side bands of the wavelength of the second returned optical signal from the first optical signal and at least one discrete spectral interference microfilter for eliminating wavelengths of the first optical signal from the second returned optical signal to the signal detector; and

signal detector receiving said second returned signal, the signal separating component operative to separate said first optical signal from said second returned signal thus to minimize cross-talk and prevent light of the first signal wavelength from entering to the signal detector.

8. An improved optical sensor as claimed in claim 7 wherein the temperature stabilized signal generating component comprises an LED assembly for generating said first optical signal of a precise first wavelength.

9. An improved optical sensor as claimed in claim 7 wherein the temperature stabilized signal generating component comprises a laser for generating said first optical signal of a precise first wavelength.

10. An improved optical sensor as claimed in claim 7 wherein the signal separating component comprises a wavelength division multiplexer including a first signal separator element and a second signal separator element, with light returning from the sensor tip first striking the first signal separator element which reflects the first signal onto a first fiber end associated with the signal indicating component, with the light that is not reflected off of the first signal separator element traveling to the second signal separator element and is reflected onto a second fiber end associated with the signal detector, thus separating the components of incoming multi-colored light and directing each component to a respective fiber.

11. A distribution system for a sensor as claimed in claim 7 wherein the signal detector for receiving said second returned optical signal comprises an avalanche photo diode (APD).

12. A distribution system for a sensor as claimed in claim 7 wherein the signal detector for receiving said second returned optical signal comprises a p*material-intrinsic material-n*material (PIN) device.

13. A distribution system for a sensor that utilizes an analyte-sensitive indicator module to monitor the concentration of an analyte, the sensor having:

a signal-generating component for producing a first optical signal of a distinct first wavelength, an indicator molecule for producing a second returned optical signal of a distinct second wavelength, the first signal wavelength being such that the intensity and temporal behavior of the signal is predictably altered by the indicator molecule so that the wavelength temporal behavior of the returned signal is predictable;

a single-fiber sensor tip that includes the indicator molecule; and

a signal-measuring compound for receiving signals from the distribution system, the distribution system comprising;

a temperature stabilized LED assembly for generating said first optical signal of a precise first wavelength;

an avalanche photodiode output signal detector;

a wavelength division multiplexer for delivering said first optical signal of a precise first wavelength to the sensor, delivering said second returned optical signal of a precise second wavelength to said output signal detector, the wavelength division multiplexer to separate said first and second signals and minimize cross-talk therebetween;

said output signal detector for receiving said second return signal from the wavelength division multiplexer and transmitting it to the signal measuring component; and

at least one discrete spectral interface micro filter for eliminating side bands of the wavelength of the second returned optical signal from the first optical signal and at least another discrete spectral interference microfilter for eliminating stray side bands of the wavelength of the first optical signal from the second returned optical signal to the avalanche photo diode,

said output signal detector receiving said second returned signal from the signal separating component and transmitting it to the signal-measuring component, the signal output is substantially smaller than the signal input, and whereby the intensity of said first signal is maximized such that the intensity of the indicator signal of a wavelength corresponding to the wavelength of the signal received by the signal-measuring component is suitable for monitoring the signal input to the distribution system.

14. A method to monitor the concentration of an analyte with a sensor that utilizes an analyte-sensitive indicator molecule wherein the signal output of the sensor is substantially smaller than the signal input, the method including the steps of:

producing a first optical signal of a precise first wavelength with a temperature stabilized signal generating component;

producing a second returned optical signal of a precise second wavelength with an indicator molecule;

predictably altering the intensity and temporal behavior of the first signal wavelength with the indicator molecule so that the wavelength and temporal behavior of the returned signal is predictable;

providing a single-fiber sensor tip that includes the indicator molecule; and

receiving signals from the distribution system with a signal-measuring component, the method further including the steps of;

generating said first optical signal of a precise first wavelength with a temperature stabilized signal generating component;

providing a signal detector;

delivering said first optical signal of a precise first wavelength to the sensor with a signal separating component, delivering said second returned optical signal of a precise second wavelength to said signal detector, and separating said first and second signals with signal interference means to minimize cross-talk therebetween;

eliminating side bands of the wavelength of the second returned optical signal from the first optical signal with at least one discrete spectral interference microfilter and eliminating the wavelength of the first optical signal from the second returned optical signal to the signal detector with at least another discrete spectral interference microfilter;

connecting a sensor tip to the signal separating component by a sensor optical fiber to transmit said first optical signal to the sensor tip, and returning the resulting indicator signal from the sensor tip to the signal separating component; and

receiving said second returned signal from said signal separating component and transmitting it to the signal-measuring component with said signal detector, maximizing the intensity of said first signal of a precise first wavelength such that the intensity of the indicator signal of a wavelength corresponding to the wavelength of the signal received by the signal-measuring component is suitable for monitoring signal input to the distribution system.