Light directing and collecting fiber optic probe

• US 5,835,649 A
• Filed: 06/02/1997
• Issued: 11/10/1998
• Est. Priority Date: 06/02/1997
• Status: Expired due to Fees

• Current Assignee: University of British Columbia
• Original Assignee: University of British Columbia
• Inventors: Blades, Michael Walter, Schulze, Hans Georg, Greek, Lloyd Shane, Turner, Robin Fredrick Bruce
• Primary Examiner(s): Lee, John D.
• Application Number:
  US08/867,621
• Time in Patent Office: 526 Days
• Field of Search: 385/12, 385/15, 385/31, 250/227.28, 250/227.29, 250/575, 250/577
• US Class Current: 385/31
• CPC Class Codes: G01N 2021/6484 Optical fibres
• CPC Class Codes: G01N 21/645 Specially adapted constructive features of fluorimeters
• CPC Class Codes: G01N 21/65 Raman scattering
• CPC Class Codes: G01N 21/8507 Probe photometers, i.e. with optical measuring part dipped into fluid sample
• CPC Class Codes: G01N 2201/0846 Fibre interface with sample, e.g. for spatial resolution
• CPC Class Codes: G02B 6/241 Light guide terminations

Abstract

A fiber-optic probe is formed by a pair of optical fibers one of which delivers light to a target zone and the other collects light from a field of view in the target zone. One of these fibers is provided with a window that opens substantially perpendicular to the longitudinal axis of the fiber and with a transverse surface oriented at an angle to the longitudinal axis of the fiber to reflect light through the window or from the window longitudinally of the axis of this fiber. Two fibers are physically interconnected to position the window on one side of and immediately adjacent to the target zone and the axial end of other fiber to deliver or receive light from another side of the target zone preferably substantially perpendicular to the one side.

Claims

1. A fiber-optic probe comprising a first optical fiber for delivering light directly into a target zone, a second optical fiber for collecting light from said target zone, a window in one of said first and second optical fibers, said window facing in a direction substantially perpendicular to a longitudinal axis of said one of said first and second optical fibers, said window being positioned adjacent to one axial end of said one fiber and defining a first side of said target zone, a reflecting surface at said one axial end of said one fiber and extending across said one fiber at an acute angle to a longitudinal axis of said one fiber to reflect light passing through said one fiber to pass through or be received from said window directly into or from said target zone and said first and second fibers are interconnected in fixed relationship with said first and second fibers in intimate side by side relationship with said window defining said first side of said target zone and an axial end of the other of said first and second optical fibers defining a second side of said target zone extending from said first side so that said light passes directly to or from said target zone through said axial end of said other fiber.

2. A fiber-optic probe as defined in claim 1 wherein said window and said axial end are substantially perpendicular so that said first and second sides of said target zone are substantially perpendicular.

3. A fiber-optic probe as defined in claim 2 wherein said window is formed in said second fiber.

4. A fiber-optic probe as defined in claim 3 wherein, said first and said second fibers have their longitudinal axes substantially parallel in that portion of said first and second optical fibers immediately adjacent to said target zone.

5. A fiber-optic probe as defined in claim 4 wherein said acute angle is 45°

.

6. A fiber-optic probe as defined in claim 3 wherein said reflecting surface on said second fiber is curved to deflect more light substantially along said longitudinal axis of said second fiber.

7. A fiber-optic probe as defined in claim 2 wherein said window has a field of view determined by the size, shape and position of said reflecting surface and corresponds with an area of said target zone to or from which said light passing longitudinally of said one fiber of said first and second fibers is directed or received.

8. A fiber-optic probe as defined in claim 7 wherein said other fiber is said first fiber and said first and second fibers are interconnected so that said axial end of said first fiber does not extend into said field of view farther than one half the length of said field of view measured parallel to said longitudinal axis of said first fiber.

9. A fiber-optic probe as defined in claim 8 wherein said reflecting surface on said second fiber is shaped to deflect more light substantially along said longitudinal axis of said second fiber.

10. A fiber-optic probe as defined in claim 2 wherein said second optical fiber has a cross-sectional area greater than that of said first fiber.

11. A fiber-optic probe as defined in claim 2 wherein a pair of said second fibers are arranged to be diametrically opposed relative to said first optical fiber.

12. A fiber-optic probe as defined in claim 11 wherein an anti-reflection coating, suitable for wavelength(s) being used, to reduce losses of light caused by scattering from fiber surfaces is applied to said window and said axial end.

13. A fiber-optic probe as defined in claim 11 wherein a filter optical coating suitable for the wavelength(s) being used to permit the selective transmission of light of desired wavelength(s) by into said target zone and reduce transmission of light of undesired wavelengths into the target volume and with filter coating, suitable for the wavelength(s) being used, to permit the transmission of light of desired wavelength(s) from the target volume into said second optical fiber and to reduce collection of light of undesired wavelengths from the said target volume.

14. A fiber-optic probe as defined in claim 2 wherein an anti-reflection coating, suitable for wavelength(s) being used, to reduce losses of light caused by scattering from fiber surfaces is applied to said window and said axial end.

15. A fiber-optic probe as defined in claim 2 wherein a filter optical coating suitable for the wavelength(s) being used to permit the selective transmission of light of desired wavelength(s) by into said target zone and reduce transmission of light of undesired wavelengths into the target volume and with filter coating, suitable for the wavelength(s) being used, to permit the transmission of light of desired wavelength(s) from the target volume into said second optical fiber and to reduce collection of light of undesired wavelengths from the said target volume.

16. A fiber-optic probe as defined in claim 1 wherein said window is formed in said second fiber.

17. A fiber-optic probe as defined in claim 16 wherein, said first and said second fibers have their longitudinal axes substantially parallel in that portion of said first and second optical fibers immediately adjacent to said target zone.

18. A fiber-optic probe as defined in claim 17 wherein said acute angle is 45°

.

19. A fiber-optic probe as defined in claim 16 wherein said reflecting surface on said second fiber is curved to deflect more light substantially along said longitudinal axis of said second fiber.

20. A fiber-optic probe as defined in claim 1 wherein said window has a field of view determined by the size, shape and position of said reflecting surface on said window and corresponds with an area of said target zone to or from which said light passing longitudinally of said one fiber of said first and second fibers is directed or received.

21. A fiber-optic probe as defined in claim 20 wherein said other fiber is said first fiber and said first and second fibers are interconnected so that said axial end of said first fiber does not extend into said field of view farther than one half the length of said field of view measured parallel to said longitudinal axis of said first fiber.

22. A fiber-optic probe as defined in claim 21 wherein said reflecting surface on said second fiber is curved to deflect more light substantially along said longitudinal axis of said second fiber.

23. A fiber-optic probe as defined in claim 1 wherein said first fiber further includes a lens at its axial end adjacent to said target zone for directing light into said target zone.

24. A fiber-optic probe as defined in claim 1 wherein said light is deep ultraviolet light and said first fiber is a high efficiency, solarization-resistant ultraviolet light transmitting optical fiber.

25. A fiber-optic probe as defined in claim 1 wherein said second optical fiber has a cross-sectional area greater than that of said first fiber.