CN101147669A - Single-fiber endoscopy system integrating optical coherence tomography and laser-induced fluorescence spectroscopy - Google Patents

Abstract

Translated fromChinese

本发明公开了一种集成光学相干层析成像(OCT)与激光诱导荧光光谱(LIF)的单光纤内窥系统。采用光纤的波分复用技术，利用OCT与LIF两个诊断模式的工作波段不一致以及双包层光纤的双模式特性，实现OCT与LIF的单光纤内窥系统的整合。纤芯模式在为OCT诊断模式提供单模单模传输通道的同时，也作为荧光激发光的传输通道，而内包层模式则为荧光信号提供传输通道。双包层光纤耦合器将荧光信号从双包层光纤的内包层中分离出来，从而实现荧光光谱测量。本发明具有尺寸特别小，稳定性和可靠性高，成本低，以及背景干扰小的优点。

The invention discloses a single-fiber endoscopic system integrating optical coherence tomography (OCT) and laser-induced fluorescence spectroscopy (LIF). Using optical fiber wavelength division multiplexing technology, using the inconsistency of the working bands of the two diagnostic modes of OCT and LIF and the dual-mode characteristics of the double-clad optical fiber, the integration of the single-fiber endoscopic system of OCT and LIF is realized. While the core mode provides a single-mode single-mode transmission channel for the OCT diagnostic mode, it also serves as a transmission channel for the fluorescence excitation light, while the inner cladding mode provides a transmission channel for the fluorescence signal. Double-clad fiber couplers separate the fluorescence signal from the inner cladding of the double-clad fiber, enabling fluorescence spectroscopy measurements. The invention has the advantages of particularly small size, high stability and reliability, low cost, and little background interference.

Description

The single fiber endoscope system of integrated optical coherence chromatographic imaging and laser-induced fluorescence spectroscopy

Technical field

The present invention relates to optical coherent chromatographic imaging and laser-induced fluorescence spectroscopy diagnostic techniques, especially relate to the single fiber endoscope system of a kind of integrated optical coherence chromatographic imaging and laser-induced fluorescence spectroscopy.

Background technology

Developed recently gets up, and is used to diagnose the optical biopsy method of tissue pathological changes to become the general orientation that Modern Optics Technology is used.The practical technique of optical biopsy comprises spectral diagnosis of tissue and image-forming diagnose, is compared to traditional diagnosis method, and its superiority mainly shows as: (1) is reduced even is abandoned biopsy to doubtful tissue, thereby reduces patient's misery; (2) under the unusual unconspicuous situation of organizational structure, can effectively instruct the biopsy operation; (3) during clinical operation, the pathological tissues border is judged.

Optical coherent chromatographic imaging (Optical Coherence Tomography, be called for short OCT) be the chromatography imaging technique that developed recently gets up, can realize the organizational structure and the physiological function of nontransparent high scattering medium inside are carried out noncontact, not damaged, high-resolution imaging.In biomedical sector and clinical diagnosis, be used widely, can be used on the early diagnosis of diseases such as ophthalmology, skin.

Laser-induced fluorescence (LIF) (Laser Induced Fluorescence, be called for short LIF) spectrum becomes a key areas in the optical biopsy technical research with advantages such as its high resolution, sensitivity and degree of accuracy.At present, utilize laser-induced fluorescence spectroscopy to diagnose the research of various lesion tissues to carry out more deeply, comprise the pathological changes of digestive tract disease, dermatosis, angiopathy and other position tissue etc.Fluorescent radiation excites generation down by bio-tissue at the incident illumination of certain wavelength, and the fluorescent radiation band is the information of biochemical composition in a organized way.The fluorescence substrate that produces fluorescence comprise that bio-tissue carries as aminoacid, elastin laminin, keratin, vitamin and porphyrin etc. also comprise outside chemical staining agent of adding such as rhodamine etc.

Conventional OCT technology can only sampling morphologic information, and fluorescence spectrum can only be surveyed the variation of the biochemical component of tissue and can't provide the three dimensional structure image intuitively.Therefore, the integration of OCT and LIF technology will greatly promote the accuracy and the efficient of medical diagnosis on disease, especially will have higher sensitivity to primary lesion tissues such as infantile tumours.To play immeasurable impetus for prevention and treatment of diseases.

Fibre-optical probe is the critical component of endoscope system, and the miniaturization of probe then is a precondition of implementing to peep in vivo diagnosis, and imaging probe has only the miniaturization of satisfying requirement, just can enter the human intracavity, is implemented in bulk optics biopsy.The integrated of multiple optical diagnostics pattern will increase the probe optical system, the complexity of aspects such as frame for movement, thus increase probe size, and may reduce the stability and the reliability of system.In addition, the design of probe and cost of manufacture also can increase greatly.Therefore, how to integrate a plurality of diagnostic modes under the least possible optics condition is to reduce probe size, the effective way that reduces cost.The isolating design realization OCT of difunctional probe employing optical fiber of people such as A.R.Tumlinson report and LIF's is integrated.(A.R.Tumlinson，L.P.Hariri，U.Utzinger，and?J.K.Barton，“Miniature?endoscope?for?simultaneousoptical?coherence?tomography?and?laser-induced?fluorescence?measurement”，AppliedOptics，43(1)：113-121，(2004))。In their probe, a single-mode fiber is used for conducting the light source and the flashlight of OCT imaging, and a root multimode fiber is used to conduct exciting light, and other two root multimode fibers are used to conduct fluorescence signal.This design only is that two kinds of probes are being merged, and does structural integration.Because fiber count does not reduce, thereby can't be from essence system being simplified.

Summary of the invention

The object of the present invention is to provide the single fiber endoscope system of a kind of integrated optical coherence chromatographic imaging and laser-induced fluorescence spectroscopy, by adopting a kind of doubly clad optical fiber and doubly clad optical fiber bonder, make the light of OCT and two diagnostic modes of LIF all only need be incorporated into a system through a fiber-optic transfer.

The technical solution adopted in the present invention is:

Comprise light source cell, fibre optic interferometer, doubly clad optical fiber coupling unit, in spy upon head unit, LIF signals collecting and processing unit, OCT signals collecting and processing unit and computer unit; First port of second single-mode optical-fibre coupler of first single-mode optical-fibre coupler in the light source cell in single-mode fiber and fibre optic interferometer is connected, welding point in the doubly clad optical fiber coupling unit is connected with second single-mode optical-fibre coupler, second port in the fibre optic interferometer through single-mode fiber, first port of the doubly clad optical fiber bonder in the doubly clad optical fiber coupling unit is spied upon head unit in doubly clad optical fiber connects, second port of doubly clad optical fiber bonder connects the long wave pass of LIF signals collecting and processing unit through doubly clad optical fiber, band filter in OCT signals collecting and the processing unit is connected with the 3rd port in the fibre optic interferometer through single-mode fiber, and the LIF signals collecting is connected with computer unit with processing unit with the OCT signals collecting with processing unit.

Described light source cell comprises OCT light source, optoisolator, LIF light source and first single-mode optical-fibre coupler; The low-coherent light that the OCT light source sends connects second port of first single-mode optical-fibre coupler through single-mode fiber behind optoisolator, the light that the LIF light source sends connects the 3rd port of first single-mode optical-fibre coupler through single-mode fiber.

Described fibre optic interferometer comprises second single-mode optical-fibre coupler and reference arm; The collimating mirror of the 4th port of second single-mode optical-fibre coupler in single-mode fiber access reference arm, the collimating mirror in the reference arm sets gradually dispersion compensator, light-balancing filter and reflecting mirror with optical axis.

Described doubly clad optical fiber coupling unit comprises welding point, mould detacher and doubly clad optical fiber bonder; Welding point connects the mould detacher through doubly clad optical fiber, and the mould detacher connects the 3rd port of doubly clad optical fiber bonder.

Spying upon head unit in described is coaxial successively axial cone mirror, corner cube prism and the micro motor of being provided with in transparent sheath, and the axial cone mirror is connected with doubly clad optical fiber bonder first port in the doubly clad optical fiber coupling unit through doubly clad optical fiber.

In described LIF signals collecting and the processing unit, long wave pass is connected with fluorescence spectrophotometer.

In described OCT signals collecting and the processing unit, band filter is connected with the OCT signal sensor.

Compare with background technology, the present invention has following advantage:

1, spy upon head in the optical fiber of the present invention design and only adopt root optical fiber to realize the integration of optical coherent chromatographic imaging and two kinds of medical diagnosis patterns of laser-induced fluorescence spectroscopy, in spy upon the diameter that area of bed can be as small as a general single mode fiber.Can carry out optical biopsy to the cavity organization of minor diameter more, as fallopian tube, deferent duct, cerebrovascular etc.

2, single fiber structure is simplified the design and the production of contact unit optical system optics and frame for movement greatly, improves the stability and the reliability of system, reduces cost.

3, the doubly clad optical fiber bonder is realized separating of fluorescent exciting and flashlight, effectively reduces the interference of the fluorescence background of optical fiber to the histofluorescence signal itself.

Description of drawings

Fig. 1 is a structure of block diagram principle schematic of the present invention;

Fig. 2 is a system structure principle schematic of the present invention;

Fig. 3 is the structural representation of the doubly clad optical fiber among the present invention;

Fig. 4 is the light path sketch map of the reference arm that adopts among the present invention;

Fig. 5 spies upon the header structure sketch map in adopting among the present invention.

Among the figure: 1. light source cell, 2. fibre optic interferometer, 3. doubly clad optical fiber coupling unit; 4. spy upon head unit in; 5.LIF signals collecting and processing unit; 6.OCT signals collecting and processing unit; 7. computer unit; 8. single-mode fiber; 9. doubly clad optical fiber; 10.OCT light source; 11. optoisolator; 12.LIF light source; 13. single-mode optical-fibre coupler; 14. reference arm; 15. welding point; 16. mould detacher; 17. doubly clad optical fiber bonder; 18. long wave pass; 19. fluorescence spectrophotometer; 20. band filter; 21.OCT signal sensor; 22. fibre core; 23. inner cladding; 24. surrounding layer; 25. collimating mirror; 26. dispersion compensator; 27. light-balancing filter; 28. reflecting mirror; 29. axial cone mirror; 30. corner cube prism; 31. micro motor; 32. transparent sheath.

The specific embodiment

The present invention is further illustrated below in conjunction with drawings and Examples:

In Fig. 1, Fig. 2, the present invention includeslight source cell 1, fibreoptic interferometer 2, doubly clad opticalfiber coupling unit 3, in spy uponhead unit 4, LIF signals collecting andprocessing unit 5, OCT signals collecting andprocessing unit 6 andcomputer unit 7; First port of second single-mode optical-fibre coupler 13 of first single-mode optical-fibre coupler 13 in thelight source cell 1 in single-mode fiber 8 and fibreoptic interferometer 2 is connected,welding point 15 in the doubly clad opticalfiber coupling unit 3 is connected with second single-mode optical-fibre coupler, 13 second ports in the fibreoptic interferometer 2 through single-mode fiber 8, first port of the doubly cladoptical fiber bonder 17 in the doubly clad opticalfiber coupling unit 3 is spied uponhead unit 4 in doubly clad optical fiber 9 connects, second port of doubly cladoptical fiber bonder 17 connects thelong wave pass 18 of LIF signals collecting andprocessing unit 5 through doubly clad optical fiber 9,band filter 20 in OCT signals collecting and theprocessing unit 6 is connected with the 3rd port in the fibreoptic interferometer 2 through single-mode fiber 8, and the LIF signals collecting is connected withcomputer unit 7 withprocessing unit 6 with the OCT signals collecting withprocessing unit 5.

In Fig. 2, describedlight source cell 1 comprisesOCT light source 10, optoisolator 11, LIF light source and first single-mode optical-fibre coupler 13; The low-coherent light that OCTlight source 10 sends is coupled behind optoisolator 11, connects second port of first single-mode optical-fibre coupler 13 through single-mode fiber 8, and the light thatLIF light source 12 sends connects the 3rd port of first single-mode optical-fibre coupler 13 through single-mode fiber 8.OCTlight source 10 is coupled in the same single-mode fiber through single-mode optical-fibre coupler 13 with the light that LIFlight source 12 sends.

In Fig. 2, Fig. 4, described fibreoptic interferometer 2 comprises second single-mode fiber, 13reference arms 14 that are coupled; The collimating mirror 25 that the 4th port of second single-mode optical-fibre coupler 13 inserts in thereference arm 14 through single-mode fiber 8, the collimating mirror 25 in thereference arm 14 sets gradually dispersion compensator 26, light-balancing filter 27 and reflecting mirror 28 with optical axis.

In Fig. 2, described doubly clad opticalfiber coupling unit 3 compriseswelding point 15, mould detacher 16 and doubly cladoptical fiber bonder 17; Weldingpoint 15 connects mould detacher 16 through doubly clad optical fiber 9, mould detacher 16 connects the 3rd port of doubly cladoptical fiber bonder 17, at fusedfiber splice point 15, single-mode fiber 8 that core diameter is identical and doubly clad optical fiber 9 are realized coaxial welding, and mould detacher 16 guarantees that the light of transmission in described doubly clad optical fiber 9 inner claddings 23 interrupts at this place.

In Fig. 5, spying uponhead unit 4 in described is coaxial successively axial cone mirror 29, corner cube prism 30 and micro motors 31 of being provided with in transparent sheath 32, and axial cone mirror 29 is connected with doubly cladoptical fiber bonder 17 first ports in the doubly clad opticalfiber coupling unit 3 through doubly clad optical fiber 9.The imaging optical system ofcontact unit 4 is a lens imaging system, or the optical fiber lens imaging system, or the GRIN Lens imaging system.The scan pattern ofcontact unit 4 is front translation scan pattern, side translation scan pattern or side rotation sweep pattern.

In Fig. 2, in described LIF signals collecting and theprocessing unit 5,long wave pass 18 is connected with fluorescence spectrophotometer 19, andlong wave pass 18 stops that the light ofLIF light source 12 enters fluorescence spectrophotometer 19, realizes the measurement and the analysis of fluorescence spectrum, and fluorescence imaging.

In Fig. 2, in described OCT signals collecting and theprocessing unit 6,band filter 20 is connected with OCT acquisition ofsignal 21, andband filter 20 only allows the light of OCTlight source 10 wavelength to enterOCT signal sensor 21, realizes the measurement and the analysis of OCT signal.The mode of operation of OCT signal and collectingunit 6 is the time domain OCT pattern, or Fourier domain OCT pattern.

In Fig. 3, doubly cladoptical fiber bonder 17 and in spy upon between thehead unit 4 and to adopt doubly clad optical fiber 9, that is: the centre is a fibre core 22, inner cladding 23 and surrounding layer 24.In Fig. 2, doubly clad optical fiber 9 betweenwelding point 15 and the mould detacher 16 and doubleclad bonder 17 andlong wave pass 18 adopt same spline structure.Described doubly clad optical fiber 9 is the fused optic fiber of double clad or the photonic crystal fiber of double clad.

As shown in Figure 2, the low-coherent light that OCT light source 10 sends (near infrared band) is coupled into single-mode fiber 8 behind optoisolator 11, and the light that guarantees the OCT light source is with the single mode mode transfer; Simultaneously, the light (UV or bluish-green wave band) that sends of LIF light source 12 is coupled into single-mode fiber 8.Two-way light is coupled to the 3rd single-mode fiber through single-mode optical-fibre coupler 13 bindings, be divided into two-way by second single-mode optical-fibre coupler 13 again, one the road returns as with reference to light to reference arm 14 and by former road, and one the tunnel joins through fused fiber splice point 15 and a doubly clad optical fiber 9.The fibre core 22 of doubly clad optical fiber is identical with the single-mode fiber core diameter, thereby the light that guarantees the OCT light source is still with the single mode mode propagation, mould detacher 16 is used for removing the light energy that leaks to inner cladding 23,17 internal cladding modes of doubly clad optical fiber bonder carry out beam split, and the fibre core pattern is not had influence.Process fused fiber splice point 15, mould detacher 16, doubly clad optical fiber bonder 17 backs are to contact unit 4 successively for the two-way light of binding, and contact unit 4 is realized the illumination of sample, the reception and the mechanical scanning of signal.The fibre core 22 that an OCT signal that contact unit 4 receives and a fluorescence signal part enter doubly clad optical fiber, a part enters inner cladding 23.The flashlight of part inner cladding enters LIF signals collecting and processing unit 5 behind doubly clad optical fiber bonder 17, after long wave pass 18 filters out the exciting light of LIF light source, have fluorescence spectrophotometer 19 to record the fluorescence spectrum of sample, spectroscopic data is transferred to computer analysis again and is handled.The flashlight of fibre core is through double clad bonder 17, mould detacher 16, fused fiber splice point 15 is back to the light that returns at single-mode optical-fibre coupler 13 places and reference arm 14 and converges and interfere, and the interference signal of generation converts the signal of telecommunication to by OCT signal sensor 21 after band filter 20 filters; Machine is handled as calculated at last, realizes the OCT imaging.

Described reference arm comprises collimating mirror 25, dispersion compensator 26, light-balancing filter 27, reflecting mirror 28.The light that comes out from reference arm single-mode fiber 8 is behind collimating mirror 25 collimations, by inciding on the reflecting mirror 28 behind dispersion compensator 26 and the light-balancing filter 27.The effect of dispersion compensator 26 and light-balancing filter 27 is respectively in order to mate two chromatic dispersion and light intensity between the arm, to guarantee the optimal imaging quality.The reference light that returns from reflecting mirror 28 is again by be coupled the back optical fiber of reference arm of original optical path.

Spy upon head unit in described and comprise axial cone mirror 29; Corner cube prism 30; Micro motor 31; Transparent sheath 32.The light that comes out from doubly clad optical fiber 9 fibre cores 22 sections incides on the corner cube prism 30 after axial cone mirror 29 converges, the inclined-plane of corner cube prism 30 reflexes to the side with light 90 degree and shines on the sample, micro motor 31 drives corner cube prisms 30 rotations and realizes circular scannings, and the flashlight that returns from sample is again by be coupled the back optical fiber of sample arm of original optical path.

The present invention adopts the wavelength-division multiplex technique of optical fiber, utilizes the dual-mode nature of the inconsistent and doubly clad optical fiber of the service band of OCT and two diagnostic modes of LIF, realizes the integration of the single fiber endoscope system of optical coherent chromatographic imaging and laser-induced fluorescence spectroscopy.The diameter minimum of spying upon head in its optical fiber can be controlled at the size (100-200 μ m) of a general single mode fiber diameter, loses diagnostic field and have application potential in nothing/Wicresoft.

Described doubly clad optical fiber has fibre core and two transmission modes of inner cladding, and when optical wavelength during greater than the cutoff wavelength of fibre core pattern, the fibre core pattern will keep single mode transport, and inner cladding will keep multimode to transmit because diameter is bigger.In addition, because core diameter is more much smaller than inner cladding, the influence of its internal cladding mode can be ignored, and therefore, the inner cladding pattern is equal to common multimode fibre pattern.The doubly clad optical fiber probe that proposes is realized the integration of optical coherent chromatographic imaging and laser-induced fluorescence spectroscopy with an optical fiber, the single mode transport characteristic of fibre core pattern provides transmission line for OCT and fluorescent exciting, and the inner cladding pattern provides transmission line for fluorescence signal.

Claims (7)

1. the single fiber endoscope system of integrated optical coherence chromatographic imaging and laser-induced fluorescence spectroscopy is characterized in that: comprise light source cell (1), fibre optic interferometer (2), doubly clad optical fiber coupling unit (3), in spy upon head unit (4), LIF signals collecting and processing unit (5), OCT signals collecting and processing unit (6) and computer unit (7); First port of second single-mode optical-fibre coupler (13) of first single-mode optical-fibre coupler (13) in the light source cell (1) in single-mode fiber (8) and fibre optic interferometer (2) is connected, welding point (15) in the doubly clad optical fiber coupling unit (3) is connected with second single-mode optical-fibre coupler (13) second ports in the fibre optic interferometer (2) through single-mode fiber (8), first port of the doubly clad optical fiber bonder (17) in the doubly clad optical fiber coupling unit (3) is spied upon head unit (4) in doubly clad optical fiber (9) connects, second port of doubly clad optical fiber bonder (17) connects the long wave pass (18) of LIF signals collecting and processing unit (5) through doubly clad optical fiber (9), band filter (20) in OCT signals collecting and the processing unit (6) is connected with the 3rd port in the fibre optic interferometer (2) through single-mode fiber (8), and the LIF signals collecting is connected with computer unit (7) with processing unit (6) with the OCT signals collecting with processing unit (5).

2. the single fiber endoscope system of a kind of integrated optical coherence chromatographic imaging according to claim 1 and laser-induced fluorescence spectroscopy is characterized in that: described light source cell (1) comprises OCT light source (10), optoisolator (11), LIF light source (12) and first single-mode optical-fibre coupler (13); The low-coherent light that OCT light source (10) sends is behind optoisolator (11), connect second port of first single-mode optical-fibre coupler (13) through single-mode fiber (8), the light that LIF light source (12) sends connects the 3rd port of first single-mode optical-fibre coupler (13) through single-mode fiber (8).

3. the single fiber endoscope system of a kind of integrated optical coherence chromatographic imaging according to claim 1 and laser-induced fluorescence spectroscopy is characterized in that: described fibre optic interferometer (2) comprises second single-mode optical-fibre coupler (13) and reference arm (14); The collimating mirror (25) of the 4th port of second single-mode optical-fibre coupler (13) in single-mode fiber (8) access reference arm (14), the collimating mirror (25) in the reference arm (14) sets gradually dispersion compensator (26), light-balancing filter (27) and reflecting mirror (28) with optical axis.

4. the single fiber endoscope system of a kind of integrated optical coherence chromatographic imaging according to claim 1 and laser-induced fluorescence spectroscopy is characterized in that: described doubly clad optical fiber coupling unit (3) comprises welding point (15), mould detacher (16) and doubly clad optical fiber bonder (17); Welding point (15) connects mould detacher (16) through doubly clad optical fiber (9), and mould detacher (16) connects the 3rd port of doubly clad optical fiber bonder (17).

5. the single fiber endoscope system of a kind of integrated optical coherence chromatographic imaging according to claim 1 and laser-induced fluorescence spectroscopy, it is characterized in that: spying upon head unit (4) in described is coaxial successively axial cone mirror (29), corner cube prism (30) and the micro motor (31) of being provided with in transparent sheath (32), and axial cone mirror (29) is connected with doubly clad optical fiber bonder (17) first ports in the doubly clad optical fiber coupling unit (3) through doubly clad optical fiber (9).

6. the single fiber endoscope system of a kind of integrated optical coherence chromatographic imaging according to claim 1 and laser-induced fluorescence spectroscopy, it is characterized in that: in described LIF signals collecting and the processing unit (5), long wave pass (18) is connected with fluorescence spectrophotometer (19).

7. the single fiber endoscope system of a kind of integrated optical coherence chromatographic imaging according to claim 1 and laser-induced fluorescence spectroscopy, it is characterized in that: in described OCT signals collecting and the processing unit (6), band filter (20) is connected with OCT signal sensor (21).

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