Side illuminated multi point multi parameter

• US 8,909,004 B2
• Filed: 05/11/2013
• Issued: 12/09/2014
• Est. Priority Date: 01/30/2009
• Status: Active Grant

• Current Assignee: Claudio Oliveira Egalon
• Original Assignee: Claudio Oliveira Egalon
• Inventors: Egalon, Claudio Oliveira
• Primary Examiner(s): PAK, SUNG H
• Application Number:
  US13/892,274
• Publication Number:
  US 20130248697A1
• Time in Patent Office: 577 Days
• Field of Search: None
• US Class Current: 385/12
• CPC Class Codes: G01D 5/353 influencing the transmission properties of an optical fibre
• CPC Class Codes: G01D 5/35345 using Amplitude variations to detect the measured quantity
• CPC Class Codes: G01D 5/35387 using wavelength division multiplexing
• CPC Class Codes: G01F 23/2927 for several discrete levels, e.g. with more than one light-conducting sensing element
• CPC Class Codes: G01N 2021/635 Photosynthetic material analysis, e.g. chrorophyll
• CPC Class Codes: G01N 2021/6484 Optical fibres
• CPC Class Codes: G01N 2021/7736 exposed, cladding free
• CPC Class Codes: G01N 21/17 Systems in which incident light is modified in accordance with the properties of the material investigated where the material investigated is optically excited causing a change in wavelength of the incident light G01N21/63
• CPC Class Codes: G01N 21/251 Colorimeters; Construction thereof
• CPC Class Codes: G01N 21/64 Fluorescence; Phosphorescence
• CPC Class Codes: G01N 21/645 Specially adapted constructive features of fluorimeters
• CPC Class Codes: G01N 21/648 using evanescent coupling or surface plasmon coupling for the excitation of fluorescence
• CPC Class Codes: G01N 21/76 Chemiluminescence; Bioluminescence
• 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 2201/06193 Secundary in-situ sources, e.g. fluorescent particles
• CPC Class Codes: G01N 2201/062 LED's
• CPC Class Codes: G01N 2201/088 Using a sensor fibre
• CPC Class Codes: G02B 6/00 Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings

Abstract

A side illuminated multi point multi parameter optical fiber sensor that requires no sensitive coating is provided. This sensor comprises an optical fiber having at least one removed cladding section as the sensitive region, at least one probing light source that side illuminates the fiber, a power supply, a detector, a signal processor and a display. The sensitive optical fiber is optically affected by the presence of a measurand medium that can fluoresce, phosphoresce, absorb and/or scatter the probing light. This probing light is guided by the fiber core towards a detector which measures the light intensity and this light intensity is correlated with a measurand.

Claims

1. An optical analytic subsystem comprising:

a sensing optical fiber having at least one exposed core region free of cladding and free of sensitive coating or other sensitive, reactive chemical preparation;

at least one light source, each having a respective, predetermined output spectrum, the at least one light sources respectively associated with one of the at least one exposed core regions such that energizing the light source engenders a probing light to be transversely directed to side-illuminate the associated exposed core region from outside of the sensing fiber;

at least one location, the at least one locations respectively associated with one of the at least one exposed core regions, and at least one of the light sources, the location being adapted to accept inclusion of an analyte, and where the location is positioned relative to the associated exposed core region and to the associated light source'"'"'s probing light path that, where the analyte has at least one of the properties of the list;

chemiluminescence, phosphorescence, fluorescence, scattering, refraction, reflection and absorption, of light at the associated light source'"'"'s spectrum, the probing light is modified such that a resultant light signal is coupled into the sensing fiber'"'"'s core and is detectable at a terminus of the sensing fiber such as to identify a measurand of the analyte.

2. The optical analytic subsystem of claim 1 where the at least one exposed core region, the at least one location, and the at least one light source are at least two exposed core regions, at least two locations, and at least two respective light sources;

and further comprises a circuit configured to energize the light sources in a predetermined sequence.

3. The optical analytic subsystem of claim 2 where the light source energization sequencing is serial.

4. The optical analytic subsystem of claim 2 where the light source energization sequencing is substantially simultaneous.

5. The optical analytic subsystem of claim 2 where the fiber'"'"'s core is tapered.

6. The optical analytic subsystem of claim 1 where at least one of the at least one light sources emits light in the far infrared spectrum.

7. The optical analytic subsystem of claim 1 where at least one of the at least one light sources is an UV LED.

8. The optical analytic subsystem of claim 1 where the fiber is plastic.

9. The optical analytic subsystem of claim 1 further comprising a photodiode, a photodiode amplifier, and a light source power supply.

10. The optical analytic subsystem of claim 9 further comprising a display and a signal processor in mutual communication, and the signal processor in operative communication with the photodiode;

the display and signal processor configured to provide indication of the degree of a measurand of a substance that is disposed at one of the at least one locations.

11. The optical analytic subsystem of claim 10 in which the measurand comprises the identity of at least a portion of the composition of the substance.

12. The optical analytic subsystem of claim 10 in which the measurand comprises at least one of color, turbidity, and refractive index.

13. The optical analytic subsystem of claim 10 in which the at least one exposed core region is at least two distinct exposed core regions.

14. The optical analytic subsystem of claim 13 where the subsystem is configured such that the at least two exposed core regions are individually illuminated.

15. The optical analytic subsystem of claim 13 where the subsystem is configured such that the at least two exposed core regions are simultaneously illuminated.

16. The optical analytic subsystem of claim 13 where the at least two exposed core regions are at least three exposed core regions and where the subsystem is configured such that the at least three exposed core regions are illuminated sequentially in the order the regions occur along the fiber.

17. The optical analytic subsystem of claim 10 where the fiber optic, including both core and any cladding, are tapered.

19. The optical analytic subsystem of claim 1 where the optical sensing fiber is free of any core region comprising sensitive coating or other sensitive, reactive chemical preparation attached to the sensing fiber at an operational position.

18. An optical analytic subsystem comprising:

a fiber optic configured to receive light that side illuminates the fiber at least at one exposed core region free of cladding and free of sensitive coating or other sensitive, reactive chemical preparation and configured to guide said light to at least one of its termini;

at least one light source positioned and oriented to illuminate the side of said fiber optic at the at least one exposed core region and where the fiber optic is tapered proximate to at least one of the at least one exposed core regions.