JP2015027531A - Optical measurement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical measurement device suitable for measuring the distribution of lipids in a blood vessel.SOLUTION: Illumination light outputted from an optical branch part 32 is made incident on a proximal end 11a of an optical fiber 11 and emitted from a distal end 11b to irradiate an object 3 with the illumination light, back reflection light generated in the object 3 following the irradiation is made incident on the distal end of the optical fiber 11 and emitted from the proximal end to guide the back reflection light to an optical detector 33 and guide reference light outputted from the optical branch part 32 to the optical detector 33, interference light by the back reflection light and the reference light are detected by the optical detector 33, a spectrum of the back reflection light is analyzed by an analyzer 36 to generate tomographic structure information of the object and distribution information of material inside the object, and the tomographic structure information and the distribution information of the material are analyzed in combination to calculate a tomographic image in which the distribution of the material inside the object is displayed.

Description

  The present invention relates to an optical measurement apparatus that performs measurement using an optical coherence tomography (OCT) technique.

  Optical coherence tomography (OCT) is known as a technique for measuring the tomographic structure of the lumen of a luminal object such as a blood vessel, and is inserted into the lumen of the object for this OCT measurement. An optical probe to be used is also known (see Patent Document 1). For OCT measurement, a graded index optical fiber connected to the tip (distal end) of a single-mode optical fiber is made to function as a lens so that the working distance is longer than 1 mm and the spot size is smaller than 100 μm. Thus, an object having an inner radius larger than 1 mm can be optically measured with a spatial resolution finer than 100 μm.

  OCT measurement is used when diagnosing a lesion in a blood vessel and selecting a treatment method. When the lesion is subjected to OCT measurement, a tomographic image of the lesion is obtained. In the tomographic image, a site that strongly scatters light within the lesion is bright, and a site that scatters light only weakly is displayed in a single tone with a dark gradation. Since the pattern of the light / dark distribution of this image varies depending on the lesion, it is known that the type of lesion can be estimated to some extent from the light / dark pattern of the image (see Non-Patent Document 1).

US Pat. No. 6,445,939 US Patent Application Publication No. 2002/0151823

W. M. Suh, Circ CardiovascImaging. 2011; 4: 169-178

  In an OCT apparatus using a conventional optical probe, it may be difficult to identify the type of lesion. For example, it is difficult to identify a lipid lesion (lipid-rich plaque) and a calcified lesion (fibrocalcificplaque). The inventor found.

  As described in Non-Patent Document 1, lipid lesions are characterized by dark gradations and unclear outlines, and calcified lesions are characterized by dark gradations and clear outlines. However, since the gradation of the gradation is relative, it is difficult to make a judgment if there are variations due to individual differences or measurement conditions. Also, regarding the clarity of the outline, since there are various patterns of actual lesions, it is often difficult to judge this.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide an optical measurement device suitable for measuring the distribution of lipids in blood vessels.

  The optical measurement device of the present invention includes (1) an optical fiber that transmits light between a proximal end and a distal end, an optical connector connected to the optical fiber at the proximal end, and the far end. A condensing optical system for condensing light emitted from the distal end of the optical fiber, connected to the optical fiber at the distal end, and connected to the optical fiber at the distal end; A deflecting optical system for deflecting light emitted from the distal end; and extending along the optical fiber so as to surround the optical fiber; and to the optical fiber, the optical connector, the condensing optical system, and the deflecting optical system. An optical probe including a jacket tube that is rotatable with respect to the light source; (2) a light source that generates light in a wavelength band of 1.6 μm to 1.8 μm; and (3) a light that is emitted from the light source is split into two. Output as illumination light and reference light And (4) a photodetector that detects light in the wavelength band, and (5) an analysis unit that analyzes a light attenuation spectrum in the wavelength band and acquires the analysis result as image information. (6) Illumination light output from the light branching unit is incident on the proximal end of the optical fiber and emitted from the distal end to irradiate the object, and the object is generated along with the irradiation. Back-reflected light is incident on the distal end of the optical fiber, is emitted from the proximal end, is guided to the photodetector, and the reference light output from the optical branching unit is also guided to the photodetector. The interference light caused by the back reflected light and the reference light is detected by the light detector, and the spectrum of the back reflected light is analyzed by the analyzing unit, so that the tomographic structure information of the object and the inside of the object are detected. And distribution information of substances in Then, the tomographic image displaying the distribution of the substance in the object is calculated by analyzing the tomographic structure information and the distribution information of the substance together.

  It is preferred that the optical fiber has a cut-off wavelength shorter than 1.53 μm. The analysis unit extracts a spectrum component having an absorption peak in a wavelength range of 1.70 to 1.75 μm from the spectrum of the back reflected light, and generates lipid distribution information and tomographic structure information based on the spectrum component. It is preferable to calculate a tomographic image displaying lipid distribution by analyzing the lipid distribution information and the tomographic structure information together. In the analysis unit, the information on the scattering intensity of the predetermined substance in the object is held, and a solution that most closely matches the information on the scattering intensity is selected from a plurality of solutions related to the distribution of the predetermined substance. It is preferable to select.

  According to the present invention, it is possible to measure the distribution of lipids in blood vessels, which was difficult to measure with the prior art.

It is a figure which shows the structure of the OCT apparatus 1 provided with the optical probe 10 of this embodiment. It is a figure which shows the spectrum of the transmittance | permeability of each of a lipid lesion, a normal blood vessel, and lard.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a diagram illustrating a configuration of an OCT apparatus (optical measurement apparatus) 1 including an optical probe 10 according to the present embodiment. The OCT apparatus 1 includes an optical probe 10 and a measurement unit 30 and acquires an optical coherence tomographic image of the object 3.

  The optical probe 10 includes an optical fiber 11 that transmits light between a proximal end 11a and a distal end 11b, an optical connector 12 that is connected to the optical fiber 11 at the proximal end 11a, and a distal end 11b. Condensing optical system 13 and deflecting optical system 14 optically connected to optical fiber 11, support tube 15 and jacket tube 16 surrounding optical fiber 11 and extending along the optical fiber, and lumen of the jacket tube And a buffer fluid 17 filled in the container. The optical connector 12 is optically connected to the measurement unit 30. The optical fiber 11 has a cutoff wavelength shorter than 1.53 μm. The optical fiber 11, the condensing optical system 13, the deflecting optical system 14, and the buffer fluid 17 and the jacket tube 16 on the optical path coupled to the fundamental mode of the optical fiber 11 are − in the wavelength band of 1.6 μm to 1.8 μm. It has a light transmittance of 2 dB to 0 dB.

  The optical fiber 11 has a length of 1 to 2 m and is made of quartz glass. The optical fiber 11 has a transmission loss of 2 dB or less, preferably 1 dB or less in the wavelength range of 1.6 μm to 1.8 μm, has a cutoff wavelength of 1.53 μm or less, and operates in a single mode in the wavelength range. . As such an optical fiber, an optical fiber based on ITU-TG.652, G.654, and G.657 is preferable. In particular, an optical fiber compliant with ITU-TG.654A or C has a transmission loss as low as 0.22 dB / km or less at a wavelength of 1.55 μm, typically has a pure silica glass core, and has a low nonlinear optical coefficient. This is particularly preferable because noise due to nonlinear optical effects such as self-phase modulation can be reduced.

  At the distal end 11b of the optical fiber 11, a graded index (GRIN) lens as the condensing optical system 13 and a mirror as the deflecting optical system 14 are fusion-connected in series. The condensing optical system 13 condenses light emitted from the distal end 11 b of the optical fiber 11. The deflection optical system 14 deflects light emitted from the distal end 11 b of the optical fiber 11 in the radial direction.

  The lens (condensing optical system 13) and mirror (deflection optical system 14) are made of quartz glass or borosilicate glass, and have a transmission loss of 2 dB or less in the wavelength range of 1.6 μm to 1.8 μm. The mirror has a structure in which a flat reflecting surface forming an angle of 35 to 55 degrees with respect to an axis is formed on a cylindrical glass. Although this flat reflective surface can reflect light as it is, it is preferable to increase the reflectance at a wavelength of 1.6 to 1.8 μm by further depositing aluminum or gold on the reflective surface.

  The optical fiber 11 is accommodated in the lumen of the support tube 15. The support tube 15 is fixed to at least a part of the optical fiber 11 and the optical connector 12. As a result, when the optical connector 12 is rotated, the support tube 15 is also rotated with it, and the rotational torque is transmitted to the optical fiber 11, so that the optical fiber 11, the condensing optical system 13, the deflection optical system 14 and the support tube 15 are Rotate together. Thereby, compared with the case where only the optical fiber 11 is rotated, the torque loaded on the optical fiber 21 is reduced, and the optical fiber 11 can be prevented from being broken by the torque.

  It is desirable that the support tube 15 has a thickness of 0.15 mm or more and a Young's modulus of 100 to 300 GPa equivalent to that of stainless steel. The support tube 15 does not necessarily have to be connected in the circumferential direction, and may have a structure in which about 5 to 20 wires are twisted to adjust flexibility. Such a support tube is disclosed in Patent Document 2.

  The optical fiber 11, the condensing optical system 13, the deflecting optical system 14, and the support tube 15 are accommodated in the inner cavity of the jacket tube 16, and can be rotated therein. Thereby, it is prevented that the rotating part contacts the target object 3 and the target object 3 is damaged. The illumination light is emitted from the deflection optical system 14, passes through the jacket tube 16, and is irradiated onto the object 3. The jacket tube 16 is made of FEP, PFA, PTFE, PET, or nylon, has a thickness of 10 to 50 μm, and has a transparency such that a transmission loss at a wavelength of 1.6 to 1.8 μm is 2 dB or less.

  The lumen of the jacket tube 16 is filled with a buffer fluid 17. The buffer fluid 17 reduces the friction between the outer surface of the rotating support tube 15 and the inner surface of the jacket tube 16 and adjusts the amount of change in the refractive index in the optical path between the deflection optical system 14 and the jacket tube 16. The buffer fluid 17 is physiological saline, dextran aqueous solution, or silicone oil, and has a transmission loss of 2 dB or less at a wavelength of 1.6 to 1.8 μm.

  The measuring unit 30 detects a light source 31 that generates light, a light branching unit 32 that bifurcates the light emitted from the light source 31 and outputs it as illumination light and reference light, and light that has arrived from the light branching unit 32. Detected by the photodetector 33, the optical terminal 34 that outputs the reference light that has arrived from the optical branching unit 32, the reflecting mirror 35 that reflects the reference light output from the optical terminal 34 to the optical terminal 34, and the photodetector 33 And an output port 37 for outputting the result of the analysis by the analysis unit 36.

  The light output from the light source 31 in the measurement unit 30 is branched into two by the light branching unit 32 and output as illumination light and reference light. The illumination light output from the optical branching unit 32 is incident on the proximal end 11a of the optical fiber 11 through the optical connector 12, guided by the optical fiber 11, emitted from the distal end 11b, and the condensing optical system. 13 and the deflection optical system 14 irradiate the object 3. Back reflected light generated in response to the illumination light irradiation on the object 3 is incident on the distal end 11 b of the optical fiber 11 through the deflection optical system 14 and the condensing optical system 13, and is guided by the optical fiber 11. Then, the light is emitted from the proximal end 11 a and is coupled to the photodetector 33 through the optical connector 12 and the optical branching section 32.

  The reference light output from the optical branching unit 32 is emitted from the optical terminal 34, reflected by the reflecting mirror 35, and coupled to the detector 33 through the optical terminal 34 and the optical branching unit 32. The back-reflected light from the object 3 and the reference light interfere with each other at the photodetector 33, and the interference light is detected by the photodetector 33. The spectrum of the interference light is input to the analysis unit 36. In the analysis unit 36, the spectrum of the interference light is analyzed, and the distribution of the back reflection efficiency at each point inside the object 3 is calculated. A tomographic image of the object 3 is calculated based on the calculation result, and is output from the signal output port 37 as an image signal.

  Strictly speaking, the illumination light emitted from the distal end 11b of the optical fiber 11 returns to the distal end 11b of the optical fiber 11 again via the object 3 includes reflection, refraction, and scattering. However, since these differences are not essential to the present invention, these are collectively referred to as back reflection in this specification for the sake of brevity.

  In the present embodiment, in the measurement unit 30, the light source 31 generates broadband light whose spectrum is continuously spread over a wavelength range of 1.6 μm to 1.8 μm. In this wavelength range, as shown in FIG. 2, the lipid lesion has an absorption peak at a wavelength of 1.70 to 1.75 μm, and is different from a normal blood vessel in this respect. Since lard, which is a pure lipid, also has a similar absorption peak, it can be said that this absorption peak is due to lipid. Therefore, when the target 3 containing lipid is measured, the spectrum of the interference light is affected by absorption by the lipid, and shows a large attenuation at wavelengths of 1.70 to 1.75 μm compared to the adjacent wavelength band.

  Furthermore, since the spectrum of the interference light also has information on the tomographic structure of the object 3, the tomographic analysis of the object 3 is performed by selecting a wavelength band that is less affected by substance absorption and performing Fourier analysis of the spectrum. Structural information is obtained. By analyzing the tomographic structure information and the lipid absorption information together, it is possible to calculate a tomographic image displaying lipid distribution.

  In this calculation, since both the absorption of the lipid itself and the lipid distribution affect the spectrum, there can be a plurality of lipid distributions corresponding to one spectrum. However, as described in Non-Patent Document 1, it is known that lipids have a characteristic that the scattering intensity is lower than that of normal blood vessels. Therefore, a solution that best matches this known information is selected. Thus, the lipid distribution can be determined.

  Since the optical fiber 11, the condensing optical system 13, the deflecting optical system 14, the buffer fluid 17 and the jacket tube 16 are not all the same material, their refractive indexes are not necessarily equal and light can be reflected at the interface between them. . Since the reflected light generated at the interface of the optical probe 10 is detected by being mixed with the back-reflected light from the object 3, it can be a noise. However, in the present embodiment, the reflected light generated at the interface of the optical probe 10 is used for calibration of the measurement system.

  In the OCT measurement, the back reflected light from the object 3 and the reference light pass through different optical paths, so that the chromatic dispersion on the optical path may be different from each other. When the chromatic dispersion is different, the group delay time of light differs depending on the wavelength. In OCT measurement, a spectrum that is a function of wavelength is Fourier-analyzed to calculate an autocorrelation function as a function of group delay time, and a tomographic image is generated based on the calculated function. It is known that the spatial resolution decreases. This problem is that before measuring the object 3, the reference object such as a mirror is measured instead of the object 3 to measure the influence of chromatic dispersion, and data processing for compensating the dispersion based on the result is performed. It is known that this can be solved.

  However, in the present embodiment, spectral information is used not only for acquisition of tomographic images but also for estimation of material distribution, so that it is more sensitive to the influence of chromatic dispersion than conventional OCT. Therefore, in the conventional method in which the dispersion compensation process is performed before measuring the object 3, the estimation of the material distribution may be affected by the mechanical fluctuation of the measurement system that may occur during the measurement or the chromatic dispersion fluctuation due to the temperature fluctuation. . Therefore, during the measurement, it is preferable to perform the dispersion compensation processing by measuring the reflection at the interface of the optical probe 10 at the distal end 11b immediately before the measurement or immediately after the measurement.

  Specifically, the reflected light generated at the interface of the optical probe 10 at the distal end 11b and the reference light are caused to interfere with each other and detected by the photodetector 33, and the wavelength spectrum is detected by the analysis unit 36 in a plurality of limited wavelength bands. Fourier analysis is performed to calculate the autocorrelation function, the value of the chromatic dispersion is estimated so that the position of the reflection peak on the autocorrelation function does not change depending on the wavelength band used for the analysis, and the estimated chromatic dispersion is canceled out. Thus, it is preferable to perform dispersion compensation processing by numerically adding dispersion.

  In order to achieve this object, it is desirable that reflected light having an intensity that can be observed and does not saturate the photodetector 33 is generated at one interface of the optical probe 10 at the distal end 11b. In the OCT measurement, it is possible to measure a reflectance in a range of −100 to −50 dB typically. Therefore, the interface between the optical fiber 11 and the condensing optical system 13, the interface between the condensing optical system 13 and the deflecting optical system 14, the interface between the deflecting optical system 14 and the buffer fluid 17, and the buffer fluid 17 and the jacket tube 16. In any one of the interface and the interface between the jacket tube 16 and the external medium, it is desirable that the reflection is −100 to −50 dB and higher by 10 dB or more than the other interfaces.

  Here, the reflectance at the interface is the optical power reflected from the interface and recombined with the core of the optical fiber 11 with respect to the optical power emitted from the core of the optical fiber 11 at the distal end 11b and incident on the interface. It is a ratio. Therefore, the reflectance at the interface depends not only on the refractive index change at the interface but also on the shape of the interface. Since the interface between the deflection optical system 14 and the buffer fluid 17, the interface between the buffer fluid 17 and the jacket tube 16, and the interface between the jacket tube 16 and the external medium are all cylindrical, they are reflected by the effect of the shape. The rate is reduced by about 0 to 30 dB. When the object 3 is a blood vessel, the external medium existing outside the jacket tube 16 is typically blood or physiological saline, and has a refractive index (wavelength 589 nm, which is a typical refractive index evaluation wavelength). Is the same as in the following).

Therefore, one suitable combination is that the jacket tube 16 is made of FEP or PFA (refractive index 1.34), the buffer fluid 17 is physiological saline (refractive index 1.33), the optical fiber 11, and the condensing optics. This is a combination in which the system 13 and the deflection optical system 14 are made of quartz glass. At this time, the relative refractive index difference at the interface between the optical fiber 11 and the condensing optical system 13 is 0%, the relative refractive index difference at the interface between the condensing optical system 13 and the deflecting optical system 14 is 0%, The relative refractive index difference at the interface between the deflection optical system 14 and the buffer fluid 17 is 8.9%, and the relative refractive index difference at the interface between the buffer fluid 17 and the jacket tube 16 is 0.82%. The relative refractive index difference at the interface with the external medium is 0.82%. When the refractive indexes of the medium on both sides of the interface are n ₁ and n ₂ , the relative refractive index difference at the interface is defined by the formula 2 (n ₁ −n ₂ ) / (n ₁ + n ₂ ). .

  In this case, the relative refractive index difference of 8.9% at the interface between the deflection optical system 14 and the buffer fluid 17 is 11 times that of the other interfaces. Since the reflectance at the interface is proportional to the square of the relative refractive index difference, the reflectance at the interface between the deflection optical system 14 and the buffer fluid 17 is 21 dB or more higher than the reflectance at the other interfaces. Since the refractive indexes of the optical fiber 11, the condensing optical system 13, and the deflecting optical system 14 are the same, the reflectance at the interface between them can be ignored. As a result, reflections at a plurality of interfaces do not overlap on the OCT tomographic image, and the reflection peak at the interface between the deflection optical system 14 and the buffer fluid 17 can be clearly observed, and this reflection peak is used. It becomes possible to calibrate chromatic dispersion.

  DESCRIPTION OF SYMBOLS 1 ... OCT apparatus (optical measuring device), 3 ... Object, 10 ... Optical probe, 11 ... Optical fiber, 11a ... Proximal end, 11b ... Distal end, 12 ... Optical connector, 13 ... Condensing optical system, DESCRIPTION OF SYMBOLS 14 ... Deflection optical system, 15 ... Support tube, 16 ... Jacket tube, 17 ... Buffer fluid, 30 ... Measurement part, 31 ... Light source, 32 ... Light branching part, 33 ... Photo detector, 34 ... Optical terminal, 35 ... Reflection Mirror, 36 ... analyzer, 37 ... output port.

The optical measurement device of the present invention includes (1) an optical fiber that transmits light between a proximal end and a distal end, an optical connector connected to the optical fiber at the proximal end, and the far end. A condensing optical system for condensing light emitted from the distal end of the optical fiber, connected to the optical fiber at the distal end, and connected to the optical fiber at the distal end; A deflecting optical system for deflecting light emitted from the distal end; and extending along the optical fiber so as to surround the optical fiber; and to the optical fiber, the optical connector, the condensing optical system, and the deflecting optical system. An optical probe including a jacket tube that is rotatable with respect to the optical axis; (2) a light source that generates light in a wavelength band of 1.6 μm to 1.8 μm; Output as illumination light and reference light An optical branching unit, (4) a photodetector for detecting light in the wavelength band, and (5) an analysis unit for analyzing a light attenuation spectrum in the wavelength band and acquiring the analysis result as image information. (6) Illumination light output from the light branching unit is incident on the proximal end of the optical fiber and emitted from the distal end to irradiate the object, and the object is generated along with the irradiation. Back-reflected light is incident on the distal end of the optical fiber, is emitted from the proximal end, is guided to the photodetector, and the reference light output from the optical branching unit is also guided to the photodetector. The interference light caused by the back reflected light and the reference light is detected by the photodetector, and the spectrum of the interference light is analyzed by the analysis unit, so that the tomographic structure information of the object and the inside of the object are detected. to generate and distribution information of lipid The fault structure information and the By together with distribution information of lipid analysis, calculates a tomographic image displaying the distribution of the lipid inside the object.

It is preferred that the optical fiber has a cut-off wavelength shorter than 1.53 μm. The analysis unit extracts a spectrum component having an absorption peak in a wavelength range of 1.70 to 1.75 μm from the spectrum of the interference light , and generates lipid distribution information and tomographic structure information based on the spectrum component. It is preferable to calculate a tomographic image showing lipid distribution by analyzing the lipid distribution information and the tomographic structure information together. In the analysis unit, the information on the scattering intensity of the lipid inside the object is held, and a solution that most closely matches the information on the scattering intensity is selected from a plurality of solutions related to the lipid distribution. Is preferred.

The optical measurement device of the present invention includes (1) an optical fiber that transmits light between a proximal end and a distal end, an optical connector connected to the optical fiber at the proximal end, and the far end. A condensing optical system for condensing light emitted from the distal end of the optical fiber, connected to the optical fiber at the distal end, and connected to the optical fiber at the distal end; A deflecting optical system for deflecting light emitted from the distal end; and extending along the optical fiber so as to surround the optical fiber; and to the optical fiber, the optical connector, the condensing optical system, and the deflecting optical system. An optical probe including a jacket tube that is rotatable with respect to the optical axis; (2) a light source that generates light in a wavelength band of 1.6 μm to 1.8 μm; Output as illumination light and reference light An optical branching unit, (4) a photodetector for detecting light in the wavelength band, and (5) an analysis unit for analyzing a light attenuation spectrum in the wavelength band and acquiring the analysis result as image information. (6) Illumination light output from the light branching unit is incident on the proximal end of the optical fiber and emitted from the distal end to irradiate the object, and the object is generated along with the irradiation. Back-reflected light is incident on the distal end of the optical fiber, is emitted from the proximal end, is guided to the photodetector, and the reference light output from the optical branching unit is also guided to the photodetector. Detecting interference light caused by the backward reflected light and the reference light by the photodetector, and generating tomographic structure information of the object by Fourier-analyzing the spectrum of the interference light by the analysis unit ; Interference light spectrum Definitive by analyzing the absorption of light to generate distribution information of lipids in the interior of the object, the tomographic structure information and said by by combining the distribution information of the lipid analysis, the distribution of the lipid inside the object The tomographic image displaying is displayed.

Claims (4)

An optical fiber for transmitting light between a proximal end and a distal end; an optical connector connected to the optical fiber at the proximal end; and an optical fiber connected to the optical fiber at the distal end; A condensing optical system that collects light emitted from the distal end of the fiber, and a deflection that is connected to the optical fiber at the distal end and deflects light emitted from the distal end of the optical fiber Light comprising: an optical system; and a jacket tube that surrounds the optical fiber and extends along the optical fiber, and is rotatable with respect to the optical fiber, the optical connector, the condensing optical system, and the deflection optical system A probe,
A light source that generates light in a wavelength band of 1.6 μm to 1.8 μm;
A light branching unit that splits the light emitted from the light source into two to output as illumination light and reference light;
A photodetector for detecting light in the wavelength band;
An analysis unit that analyzes a light attenuation spectrum in the wavelength band and acquires the analysis result as image information,
Illumination light output from the light branching unit is incident on the proximal end of the optical fiber and emitted from the distal end to irradiate the object. The light is incident on the distal end of the optical fiber, is emitted from the proximal end, is guided to the photodetector, and the reference light output from the optical branching unit is also guided to the photodetector, and the back reflection is performed. The interference light by the light and the reference light is detected by the photodetector, and the tomographic structure information of the object and the distribution of the substance in the object are analyzed by analyzing the spectrum of the back reflected light by the analysis unit. Generating information and calculating the tomographic image displaying the distribution of the substance in the object by analyzing the tomographic structure information and the distribution information of the substance together,
Optical measuring device. The optical fiber has a cutoff wavelength shorter than 1.53 μm;
The optical measuring device according to claim 1. The analysis unit extracts a spectrum component having an absorption peak in a wavelength range of 1.70 to 1.75 μm from the spectrum of the back reflected light, and generates lipid distribution information and tomographic structure information based on the spectrum component. Then, by analyzing the lipid distribution information and the tomographic structure information together, the tomographic image displaying the lipid distribution is calculated.
The optical measuring device according to claim 1 or 2. In the analysis unit, information on the scattering intensity of the predetermined substance in the object is held, and a solution that most closely matches the information on the scattering intensity is selected from a plurality of solutions related to the distribution of the predetermined substance. ,
The optical measuring device according to claim 1 or 2.

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