JPH075107A - Spectroscopic fiber scope - Google Patents

Abstract

PURPOSE:To provide a spectroscopic fiber scope which can produce a two-dimensional image by measuring the geometric information and the spectroscopic information of a specimen temporally and spatially with high efficiency. CONSTITUTION:The spectroscopic fiber scope comprises a light source 21 emitting a pulse laser light (a), a single mode image optical fiber 24 having light dispersing properties, and a circuit 31 for controlling the output from a two-dimensional optical detector 33 such that the output signal therefrom is split in time series. Fluorescent light (b) having a spectral width lambda1-lambdan, emitted from a specimen 10, impinges on the optical fiber 24 which outputs a light (c) having time shifts among respective spectra lambda1, lambda2,..., lambdan. The control circuit 31 subjects the output signals from the two-dimensional optical detector 33 to time sharing thus obtaining the intensity of individual spectrum from the light (c).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a split optical fiber scope, and more particularly to a split optical fiber scope for measuring shape information and spectral information of a sample.

[0002]

2. Description of the Related Art Conventionally, as a means for simply measuring spectral information, a spectrum of light from a point light source is spread on one axis of space by a dispersive element such as a prism or a diffraction grating, and the spread axis of this spectrum is spread. There is one that detects the intensity of each spectrum by a photodetector such as a linear sensor arranged along the line.

However, in the fields of medicine and biology, not only spectral information is obtained, but also morphological information is simultaneously measured, and image information in which spectral information and morphological information are organically combined is required. This is because it is very useful for elucidating the function of the structure, which is its morphological information.

A microscope using an interference filter is one that simultaneously measures spectral information and morphological information in this way. This microscope is to obtain an image of light in a specific wavelength range by injecting light (for example, fluorescence) emitted from a specimen into an image sensor or an eyepiece lens through an interference filter,
The obtained image has both spectral information and morphological information. However, the spectral information obtained by this method is the spectral information of only the wavelength range of the interference filter set in advance, and in order to obtain the spectral information of the light of the unknown wavelength range, a plurality of types of interference filters are used as described above. Is performed multiple times, and spectral information is obtained based on the obtained multiple spectral information and pre-recognized a priori information (for example, the constraint condition that the spectrum of any substance does not become negative at any wavelength). It is necessary to match with morphological information (“Optics”, Vol. 18, No. 1 (January 1989), Pattern analysis by imaging spectroscopy).

Further, the light emitted from the specimen is split into two lights by an optical path splitting means such as a beam splitter, the morphological information is obtained from one of the split lights using the image pickup device, and the other is split using the spectroscope. There is a method of obtaining spectral information from the light of the above ("Optical Alliance" (August 1991) Cancer diagnosis using fluorescence from substances having tumor affinity).

[0006]

However, the measuring method for linking the spectral information and the morphological information based on a plurality of filters and a priori information needs to be measured for each filter in different wavelength bands, The problem is that it takes a lot of time.

Further, the spectral information obtained by the method of obtaining the morphological information and the spectral information using the image pickup device and the spectroscope is:
Since it is the averaged spectral information of the entire image, it does not organically combine the spectral information and the morphological information.

Further, since a general spectroscopic measurement device develops a spectrum of light on one axis of space, it is impossible to capture a two-dimensional image by a two-dimensional multi-channel detector.
It is necessary to develop the image data on the time axis using a scanning optical system. Therefore, it is necessary to secure a scanning time and a scanning space for imaging.

The split optical fiber scope of the present invention has been made in view of the above circumstances, and is a split optical fiber for efficiently measuring the morphological information and the spectral information temporally and spatially and converting these information into a two-dimensional image. It is intended to provide a scope.

[0010]

In the split optical fiber scope of the present invention, light emitted from a specimen, that is, light in which a plurality of spectra are temporally superposed, is incident on a single mode image optical fiber having a light dispersive property. In this case, since the propagation modes of each spectrum in the optical fiber are different from each other, the time required to emit from the optical fiber depends on the wavelength of each spectrum, and these multiple spectra emitted from the optical fiber are detected. It is characterized in that the means measures the spectral information by temporally dividing by means.

That is, the split optical fiber scope of the present invention, as described in claim 1, has a first excitation light source for emitting pulsed excitation light for irradiating the specimen, and a first light emitted from the specimen by the irradiation of the pulsed excitation light. A first image forming optical system for forming an image on an image forming surface, and an incident end on the first image forming surface,
A single mode image optical fiber having a light dispersive property, which guides the light from the specimen imaged by the first imaging optical system from the incident end to the emission end, and the emission end of the optical fiber. A second image forming optical system for forming an image of the emitted light on a second image forming surface, a two-dimensional photodetector provided on the second image forming surface, and an output signal of the two-dimensional photodetector. And a two-dimensional spectroscopic detection unit that is a detection unit that detects and is divided in time series.

Accordingly, in the optical fiber scope, the detecting means includes a photodetector driving means for time-sequentially dividing the output signal of the two-dimensional photodetector and an output signal of the two-dimensional photodetector obtained by the division. It is possible to use a storage means for storing. It is also possible to employ a configuration including a waveform measuring unit that measures the waveform of the output signal of the two-dimensional photodetector and a signal processing unit that divides the output signal measured by the waveform measuring unit in time series. Further, it is provided between the second image forming optical system and the second image forming surface, and the light from the sample formed by the second image forming optical system is imaged based on a predetermined signal. Openable and closable shutter means for allowing or blocking passage to the two-dimensional photodetector;
It is also possible to adopt a configuration including a shutter opening / closing means for outputting the predetermined signal to the shutter means, and a storage means for storing the output signal detected by the photodetector when the shutter means is in the open position.

It is preferable that the single mode image optical fiber has a large dispersibility in order to more appropriately time-divide a plurality of temporally superposed spectra and further facilitate detection.

[0014]

According to the optical fiber scope of the present invention, the pulsed excitation light emitted from the excitation light source irradiates the entire specimen, and the specimen is excited by the pulsed excitation light and has a certain wavelength width than the entire specimen. It emits light (for example, fluorescence). The light emitted from this sample consists of a plurality of spectra in this wavelength band and is temporally superimposed. This light is imaged on a predetermined image forming surface by the first image forming optical system, and the light imaged on this image forming surface has an incident end on the image forming surface and is guided to an emitting end. It is incident on a single mode image optical fiber having a light dispersive property. The light emitted from the sample incident on this optical fiber is
Propagation modes are different for each wavelength of each spectrum in the optical fiber, and thus a plurality of spectra forming the light are emitted from the emission end of the optical fiber with a time shift for each wavelength.

The light composed of a plurality of spectra that is emitted with a temporal shift is imaged on a predetermined image forming plane by the second image forming optical system. The intensity of the imaged light is detected by a two-dimensional photodetector arranged on the predetermined imaging plane.

Here, since the detection means detects the output of the two-dimensional photodetector by dividing it in time series, a plurality of spectra emitted from the optical fiber with a time lag are detected for each spectrum. It becomes possible. By performing this action in each optical fiber forming the single-mode image optical fiber and each photodetecting element forming the two-dimensional photodetector, spectral image information can be obtained.

Further, morphological image information can be obtained by optically superimposing spectral image information for each spectrum.

In order to detect the output of the two-dimensional photodetector by dividing it in time series, the waveform of the output signal of the two-dimensional photodetector is measured, and then the measured waveform is divided in time series. Alternatively, the light emitted from the optical fiber (the light having the plurality of spectra) may be sequentially divided in time series for each spectrum by the shutter means, and the light may be detected.
The light may be incident on the three-dimensional photodetector.

The output waveform of the two-dimensional photodetector may be temporarily stored in a storage means such as a memory, and then each spectrum may be divided from the storage means in time series and detected.

As described above, according to the optical fiber scope of the present invention, the morphological information and the spectral information can be efficiently measured in time and space, and these information can be easily converted into a two-dimensional image. it can.

[0021]

Embodiments of the split optical fiber scope of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a schematic block diagram showing a first embodiment of the optical fiber scope according to the present invention. The illustrated fiber optic scope emits a pulsed laser light a by a driver 32 that drives a laser light source 21 that emits a laser light so as to emit a pulsed laser (pulse laser) light a. , Spectral width λ
An excitation laser light source 21 for irradiating the specimen 10 having a fluorescent substance (not shown) that emits fluorescence b of 1 to λn with the pulsed laser light a, and a fluorescence b emitted by the specimen 10 upon being irradiated with the pulsed laser light a. A first condensing lens 22 for forming an image on the first image forming surface K and an incident end on the image forming surface K, and guides the fluorescent light b incident from the incident end to the emitting end. Is provided on the image forming surface L, and a single-mode image optical fiber 24 having the following: a second condensing lens 23 for forming an image of the fluorescence c emitted from the emitting end of the optical fiber 24 on the second image forming surface L; The two-dimensional photodetector 33 and the detecting means 30 for detecting the output signal of the two-dimensional photodetector 33 by time-sequentially dividing it.

Here, the single-mode optical fiber having the light dispersive property, as shown in FIG. 2, has different wavelengths as a result of the passage of a fluorescence pulse formed by temporally superimposing a plurality of spectra having different wavelengths. Single-mode optical fiber 24 that emits multiple spectra dispersed in time
It means an optical fiber formed by bundling a plurality of i, and one having a larger dispersibility is preferable in order to increase dispersion between spectra.

Further, in detail, the detecting means 30 is arranged so as to divide the output signal of the two-dimensional photodetector 33 in time series.
The control circuit 31 controls the output of the two-dimensional photodetector 33, and the memory 34 stores the output signal of the two-dimensional photodetector 33 obtained by division.

Further, the two-dimensional photodetector 33 has a number of photodetecting elements corresponding to each optical fiber 24i forming the image optical fiber 24 in a one-to-one relationship.

Next, the operation of this embodiment will be described.

Based on the control signal from the control circuit 31, the driver 32 outputs the pulse drive signal shown in FIG. 3 (a) to the laser light source 32, whereby the pulsed laser light a is emitted from the laser light source 32, The sample 10 is uniformly irradiated with the pulsed laser light a through the mirror. The fluorescent substance in the specimen 10 is excited by the pulsed laser light a, and a pulsed fluorescence b having a time width τ1 shown in FIG.
Is emitted. This fluorescence b is light having a spectral width of λ1 to λn, and is light in which a plurality of spectra λ1, λ2, ..., λn are temporally superposed.

Fluorescence b emitted from a certain point of the specimen 10 is imaged on the first image plane K by the first condenser lens 22, and the fluorescence b imaged on the image plane K is single. It is incident on the mode optical fiber 24i. The fluorescence b incident on the optical fiber 24i has a different propagation mode for each spectrum λ1, λ2, ..., λn in the optical fiber 24i, so that a time shift (delay) occurs for each spectrum λ1, λ2 ,. ) Is generated and emitted from the emitting end of the optical fiber 24i as light c having a time width τ2 (τ2> τ1) (FIG. 3 (c)).
).

The light c having a time width τ2 consisting of a plurality of spectra λ1, λ2, ..., λn is imaged on the second image plane L by the second condenser lens 23. The light c imaged on the image plane L is generated by the two-dimensional photodetector 33 arranged along the image plane L.
The intensity is detected by the photodetector element corresponding to the optical fiber 24i.

Here, the control circuit 31 outputs a photodetector drive signal shown in FIG. 3 (d), which is synchronized with the pulse of the pulsed laser light a, whereby the output signal of the two-dimensional photodetector 33 (time width τ2 , Signals of a plurality of spectra λ1, λ2, ..., λn included in the output signal are time-divided and specially input to the memory 34.

The above-described operation is performed for each optical fiber 24i that constitutes the image optical fiber 24 and the photodetector element that constitutes each pixel of the two-dimensional photodetector, so that the spectrum of fluorescence from each point of the specimen 10 is obtained. The information is stored in the memory 34 as two-dimensional image information. This allows the memory 34
The two-dimensional spectral image information of the sample 10 is stored in. Further, two-dimensional morphological image information of the sample 10 can be obtained by synthesizing the intensity signals of all the spectra λ1, λ2, ..., λn for each pixel in the memory 34.

The two-dimensional spectroscopic image information and the two-dimensional morphological image information thus obtained are output to the CRT 41 as a visible image.

As described above, according to the optical fiber scope of the present embodiment, the morphological information and the spectral information can be efficiently measured temporally and spatially, and these information can be easily converted into a two-dimensional image. can do.

FIG. 4 is a schematic block diagram showing a second embodiment of the optical fiber scope according to the present invention. The illustrated optical fiber scope has the same configuration as that of the first embodiment except that the detecting means 50 is different. Detection means 50
Is a waveform measuring unit 36 that measures the waveform of the output signal of the two-dimensional photodetector 33 shown in FIG. 3C, and a control circuit that outputs a control signal synchronized with the control signal to the driver 32 to the waveform measuring unit 36. 35
And a signal processing unit 37 that divides the output signal measured by the waveform measuring unit 36 in time series.

Next, the operation of this embodiment will be described.

The light c having the time width τ2 emitted from the optical fiber 24i by the same operation as in the first embodiment is imaged on the second image plane L by the second condenser lens 23. Image plane L
The intensity of the light c imaged on is detected by the photodetector element corresponding to the optical fiber 24i of the two-dimensional photodetector 33 arranged along the image formation plane L.

The signal of the light intensity detected by the two-dimensional photodetector 33 is converted into a plurality of spectra λ by the waveform measuring section 36.
Waveform in which 1, λ2, ..., λn are temporally superimposed (Fig. 3 (c)
See)). The waveform of the light intensity signal is converted into a plurality of spectra λ1, λ2, ... In the signal processing unit 37 by sampling signals according to the delay time of each spectrum λ1, λ2, ..., λn as shown in FIG. 3 (d). , Λn
Intensity signals are time-shared.

The above-described operation is performed for each optical fiber 24i forming the image optical fiber 24 and the photodetecting element forming each pixel of the two-dimensional photodetector, so that the spectrum of fluorescence from each point of the specimen 10 is obtained. Information can be obtained two-dimensionally, and all spectra λ1,
Two-dimensional morphological image information of the specimen 10 can be obtained by combining the intensity signals of λ2, ..., λn.

The two-dimensional spectral image information and the two-dimensional morphological image information thus obtained are output to the CRT 41 as a visible image.

As described above, according to the optical fiber scope of this embodiment, the morphological information and the spectral information can be efficiently measured in time and space, and these information can be easily two-dimensionally imaged. can do.

FIG. 5 is a schematic block diagram showing a third embodiment of the optical fiber scope according to the present invention. The illustrated optical fiber scope has the same configuration as that of the first and second embodiments except that the detecting means 60 is different. The detecting means 60 is arranged between the second condenser lens 23 and the two-dimensional photodetector 33, and comprises a plurality of spectra λ1, λ2, ..., λn formed by the second condenser lens 23. A shutter 61 that moves between an open position that allows passage of the light c to the two-dimensional photodetector 33 and a closed position that blocks passage of the light c based on a predetermined sampling signal, and the shutter 61 uses the predetermined sampling signal. And a memory 39 for storing the output signal detected by the two-dimensional photodetector 33 when the shutter 61 is at the open position.

Next, the operation of this embodiment will be described.

FIG. 6 (a) shows the waveform of the pulsed excitation light a output from the laser light source 21, and FIG. 6 (b) shows a plurality of spectra λ1, λ2, ..., λn emitted from the optical fiber 24i which are temporally superposed. Waveform of light c, (c) is shutter 61 from control circuit 38
The waveforms of the sampling signals output to are shown respectively.
According to the optical fiber scope of the present embodiment, the light c having the time width τ2 emitted from the optical fiber 24i by the same operation as that of the first embodiment is transmitted by the second condenser lens 23 to the second image plane. When the shutter 61 is in the open position, the light c passes through the shutter 61 and reaches the two-dimensional photodetector 33. On the other hand, when the shutter 61 is in the closed position, this light c is blocked by the shutter 61 and does not reach the two-dimensional photodetector 33.

The shutter 61 is normally in the closed position. First, the control circuit 38 outputs the sampling signal S1 based on the delay time t1 of the spectrum λ1 shown in FIG. 6 (c) to the shutter 61, and the shutter 61 outputs the delay time t1. Only move to the open position. By moving the shutter 61 to the open position, only the spectrum λ1 is detected by the two-dimensional photodetector 33, and the intensity signal of the detected spectrum λ1 is stored in the memory 39. Then, the control circuit 38 outputs the sampling signal S2 based on the delay time t2 of the spectrum λ2 to the shutter 61, and the shutter 61 moves to the open position for the delay time t2, and by moving the shutter 61 to the open position, the spectrum λ2. Only the two-dimensional photodetector 33 detects the intensity signal of the detected spectrum λ2 and stores it in the memory 39. The same effect applies to all spectra λ1, λ2, ..., λ
n for all spectra λ 1,
The intensities of λ2, ..., λn are stored separately to obtain spectral information.

The above operation is performed for each optical fiber 24i forming the image optical fiber 24 and the photodetecting element forming each pixel of the two-dimensional photodetector, whereby the sample
The fluorescence spectrum information from each of the 10 points can be obtained two-dimensionally, and all the spectra λ1, λ for each pixel.
The two-dimensional morphological image information of the specimen 10 can be obtained by combining the intensity signals of 2, ..., λn.

The two-dimensional spectral image information and the two-dimensional morphological image information thus obtained are output to the CRT 41 as a visible image.

According to the optical fiber scope of the present embodiment, as described above, the morphological information and the spectral information can be efficiently measured temporally and spatially, and these information can be easily two-dimensionally imaged. can do.

The split optical fiber scope of the present invention is a single-mode optical fiber having the above-mentioned conical light dispersion.
Two-dimensional image information is obtained by using a single-mode image optical fiber 24 that bundles a plurality of 24i. However, when simply trying to obtain the spectral information at one point of the sample, the single-mode light having this light dispersibility is used. It is also possible to use only one fiber 24i and use it as a spectroscopic device.

[Brief description of drawings]

FIG. 1 is a first part of an optical fiber scope according to the present invention.
Block diagram showing an embodiment of

FIG. 2 is an explanatory diagram for explaining the action of a single-mode image optical fiber having a light dispersion property.

3A is a waveform diagram showing a waveform of a pulse drive signal output from a driver 32. FIG. 3B is a waveform diagram showing a waveform of pulsed fluorescence b having a time width τ1 emitted from the specimen 10. FIG. Waveform diagram showing the waveform of light c with time width τ2 emitted from 24i (d) Waveform diagram showing the waveform of the photodetector drive signal output from control circuit 31

FIG. 4 is a second part of the optical fiber scope according to the invention.
Block diagram showing an embodiment of

FIG. 5 is a third part of the optical fiber scope according to the invention.
Block diagram showing an embodiment of

FIG. 6 (a) is a waveform diagram showing the waveform of the pulsed excitation light a output from the laser light source 21. (b) A plurality of spectra λ emitted from the optical fiber 24i.
1, λ2, ..., λn Waveform diagram showing the waveform of light c temporally superimposed (c) Waveform diagram showing the waveform of the sampling signal output from the control circuit 38 to the shutter 61

[Explanation of symbols]

 10 Sample 21 Laser light source 22, 23 Condenser lens 24 Single mode image optical fiber 24i Single mode optical fiber 30, 50, 60 Detection means 31, 35, 38 Control circuit 32 Driver 33 Two-dimensional photodetector 34, 39 Memory 36 Waveform Measuring unit 37 Signal processing unit 41 CRT 61 Shutter

Claims (4)

[Claims] 1. An excitation light source that emits pulsed excitation light for irradiating a sample, and a first imaging optical system that forms an image of light emitted from the sample by irradiation of the pulsed excitation light on a first imaging surface. , Having an incident end on the first image forming surface and guiding light from the specimen imaged by the first image forming optical system from the incident end to the emitting end, and having light dispersibility A single-mode image optical fiber, a second image-forming optical system that forms an image of the light emitted from the emission end of the optical fiber on a second image-forming surface, and a second image-forming surface. Two-dimensional photodetector and the two
A two-dimensional spectroscopic detection unit including a detection unit configured to detect an output signal of a three-dimensional photodetector by time-divisionally dividing the optical fiber scope. 2. The photodetector driving means for dividing the output signal of the two-dimensional photodetector in time series, and the output signal of the two-dimensional photodetector obtained by the division. 2. The split optical fiber scope according to claim 1, further comprising a storage means. 3. The waveform measuring means for measuring the waveform of the output signal of the two-dimensional photodetector, and the signal processing means for dividing the output signal measured by the waveform measuring means in time series. The optical fiber scope according to claim 1, wherein the optical fiber scope comprises: 4. The detecting means is provided between the second image forming optical system and the second image forming surface, and is connected by the second image forming optical system based on a predetermined signal. Shutter means for moving between an open position that allows passage of the imaged light to the two-dimensional photodetector and a closed position that blocks passage of the light, and shutter opening and closing for outputting the predetermined signal to the shutter means. 2. The split optical fiber scope according to claim 1, comprising means and storage means for storing the output signal detected by the two-dimensional photodetector when the shutter means is in the open position.