WO2019044410A1 - Light observation device - Google Patents

Abstract

A light observation device according to an embodiment of the present disclosure comprises: a first light reception unit for, if irradiation light has been irradiated onto a portion or more of an object, receiving first light including ambient light and at least one type of light selected from the group consisting of reflected light that has returned from the portion or more of the object and fluorescence emitted from the portion or more of the object and outputting a first output signal expressing the received light intensity of the first light; a second light reception unit that is provided in a position that does not overlap with the optical path of said at least one type of light and is for receiving second light including the ambient light and outputting a second output signal expressing the received light intensity of the second light; and a signal processing circuit. The signal processing circuit attenuates a first signal component of the first output signal that corresponds to the ambient light on the basis of computation carried out on the first output signal and second output signal.

Description

Optical observation device

The present disclosure relates to a light observation device.

Heretofore, methods for analyzing an object using fluorescence characteristics have been developed. For example, Patent Documents 1 to 4 disclose that an object is analyzed by acquiring Excitation Emission Matrix (EEM) information. EEM information is also referred to as "fluorescent fingerprint" and means three-dimensional data obtained by measuring a fluorescence spectrum while continuously changing the wavelength of excitation light to be applied to a sample. In addition, a technology has been conventionally developed to obtain information on an object by irradiating the object with light and measuring the reflected light from the object.

Unexamined-Japanese-Patent No. 2010-185719 Patent No. 3706914 JP, 2010-266380, A Patent No. 5985709

However, in the above-mentioned conventional technique for measuring a fluorescent fingerprint, conditions under which analysis of an object is possible are limited to limited conditions such as in a dark room or a turned-off laboratory or in a measuring apparatus. In addition, it is not possible to detect an object that does not emit fluorescence. Thus, the prior art can only be used under limited use conditions and has low versatility.

Thus, the present disclosure provides a highly versatile light observation apparatus.

A light observation apparatus according to an aspect of the present disclosure is a group of reflected light returned from at least a part and fluorescence generated from the at least part when irradiated light is irradiated to at least part of an object. A first light receiving unit that receives a first light including at least one selected light and an ambient light, and outputs a first output signal representing a light receiving intensity of the first light; A second light receiving unit provided at a position not overlapping the optical path of one light, receiving a second light including the ambient light, and outputting a second output signal representing a light receiving intensity of the second light , Signal processing circuit. The signal processing circuit attenuates a first signal component corresponding to the ambient light from the first output signal by calculation of the first output signal and the second output signal.

In the light observation device according to another aspect of the present disclosure, fluorescence generated from the object when irradiation light having an excitation wavelength selected from a plurality of different excitation wavelengths is irradiated to the object, And a signal processing circuit that receives a first light including ambient light and outputs a first output signal representing a received light intensity of the first light. The signal processing circuit is a signal component included in the first output signal, and a signal component whose correlation between the signal intensity of the signal component and the excitation wavelength is smaller than a reference value corresponds to the ambient light. The first output signal is attenuated as a signal component of one.

Further, a computer readable recording medium according to an aspect of the present disclosure is a computer readable recording medium storing a program, and when the program is executed by the computer, the first light receiving unit includes: At least one light selected from the group consisting of the reflected light returned from the at least one part and the fluorescence generated from the at least one when the irradiation light is irradiated to at least one part of the object, and the ambient light , And outputting a first output signal representing the received light intensity of the first light, and receiving a second light including the ambient light in a second light receiving unit Outputting a second output signal representing the received light intensity of the second light, and the signal processing circuit calculating the first output signal and the second output signal. A step of the first output signal attenuating a first signal component corresponding to the ambient light, is executed.

A computer readable recording medium according to another aspect of the present disclosure is a computer readable recording medium storing a program, wherein the first light receiving unit when the program is executed by the computer. The first light including the fluorescent light generated from the target and the ambient light when the target is irradiated with illumination light having an excitation wavelength selected from a plurality of different excitation wavelengths, Outputting a first output signal representing the received light intensity of the first light, and the signal processing circuit including a signal component included in the first output signal, the signal intensity of the signal component and the excitation wavelength Attenuating from the first output signal a signal component whose correlation with is smaller than a reference value as a first signal component corresponding to the ambient light.

According to the present disclosure, a highly versatile light observation apparatus can be provided.

FIG. 1 is a block diagram showing the configuration of the light observation apparatus according to the first embodiment. FIG. 2 is a diagram showing a specific configuration of the light source unit and the first light receiving unit of the light observation device according to the first embodiment. FIG. 3 is a diagram showing an example of an ideal fluorescent fingerprint when there is no ambient light. FIG. 4 is a flowchart showing the operation of the light observation apparatus according to the first embodiment. FIG. 5 is a diagram showing an example of the spectrum of ambient light. FIG. 6 is a diagram showing an example of a fluorescent fingerprint based on an output signal output from the first light receiving unit of the light observation device according to the first embodiment. FIG. 7 is a diagram showing an output signal output from the first light receiving unit of the light observation device according to the first embodiment. FIG. 8 is a view showing an example of a fluorescent fingerprint based on a signal generated by the signal processing circuit of the light observation apparatus according to the first embodiment, in which a signal component corresponding to ambient light is attenuated. FIG. 9 is a diagram showing a signal generated by the signal processing circuit of the light observation apparatus according to the first embodiment, in which a signal component corresponding to ambient light is attenuated. FIG. 10 is a block diagram showing the configuration of the light observation apparatus according to the second embodiment. FIG. 11 is a flowchart showing an operation of the light observation device according to the second embodiment. FIG. 12 is a diagram illustrating an example of a fluorescent fingerprint based on light received by the first light receiving unit of the light observation device according to the second embodiment when the excitation light is not irradiated to the object. FIG. 13 is a block diagram showing the configuration of the light observation apparatus according to the third embodiment. FIG. 14 is a block diagram showing a configuration of a light observation apparatus according to a modification of the third embodiment. FIG. 15 is a block diagram showing the configuration of the light observation apparatus according to the fourth embodiment. FIG. 16 is a diagram schematically showing the principle of the light observation device according to the fourth embodiment. FIG. 17 is a diagram showing time change of a signal output from the first light receiving unit of the light observation device according to the fourth embodiment. FIG. 18 is a diagram showing time change of a signal output from the second light receiving unit of the light observation device according to the fourth embodiment. FIG. 19 is a diagram illustrating a signal generated by the signal processing circuit of the light observation device according to the fourth embodiment, in which a signal component corresponding to ambient light is attenuated from the first output signal.

(Summary of this disclosure)
A light observation apparatus according to an aspect of the present disclosure is a group of reflected light returned from at least a part and fluorescence generated from the at least part when irradiated light is irradiated to at least part of an object. A first light receiving unit that receives a first light including at least one selected light and an ambient light, and outputs a first output signal representing a light receiving intensity of the first light; A second light receiving unit provided at a position not overlapping the optical path of one light, receiving a second light including the ambient light, and outputting a second output signal representing a light receiving intensity of the second light , Signal processing circuit. The signal processing circuit attenuates a first signal component corresponding to the ambient light from the first output signal by calculation of the first output signal and the second output signal.

Thereby, even when environmental light is irradiated to the object, the influence of the environmental light can be suppressed by attenuating the signal component corresponding to the environmental light from the first output signal. Therefore, the light observation device according to this aspect is not limited to limited conditions such as a dark room, and can be used, for example, for component analysis of an object located in a space illuminated by indoor illumination light. Thus, according to this aspect, it is possible to provide a highly versatile light observation apparatus.

In addition, since the light observation device includes the second light receiving unit, the light including at least one light selected from the group consisting of the reflected light returned from the object by the first light receiving unit and the fluorescence generated from the object At the same time as receiving light, the second light receiving unit can receive light not including the at least one light. For example, since the second light receiving unit can be used exclusively for receiving the ambient light, the received light intensity of the ambient light can be accurately obtained without being affected by the disturbance light. Therefore, since the accuracy of light observation is enhanced, the detection accuracy of the object can also be enhanced.

Also, for example, the irradiation light may have an excitation wavelength selected from a plurality of different excitation wavelengths, and the first light may include the fluorescence.

Thereby, an organic substance or the like that emits fluorescence can be detected. For example, human vomit and pollen can be detected.

Also, for example, the first light may include the reflected light.

Thereby, particulate matter such as PM 2.5 which does not emit fluorescence can be detected.

Also, for example, in the light observation device according to an aspect of the present disclosure, each of the first light receiving unit and the second light receiving unit includes a plurality of pixels, and the first light receiving unit and the second light receiving unit The light receiving unit may constitute an image sensor.

Thus, one image sensor can be shared as the first light receiving unit and the second light receiving unit, so that the configuration of the light observation apparatus can be simplified.

In the light observation device according to another aspect of the present disclosure, fluorescence generated from the object when irradiation light having an excitation wavelength selected from a plurality of different excitation wavelengths is irradiated to the object, And a signal processing circuit that receives a first light including ambient light and outputs a first output signal representing a received light intensity of the first light. The signal processing circuit is a signal component included in the first output signal, and a signal component whose correlation between the signal intensity of the signal component and the excitation wavelength is smaller than a reference value corresponds to the ambient light. The first output signal is attenuated as a signal component of one.

While the intensity of fluorescence depends on the excitation wavelength, the intensity of ambient light does not depend on the excitation wavelength. That is, it is assumed that the component having a small correlation between the signal intensity and the excitation wavelength is a component containing a large amount of ambient light. Therefore, by attenuating the component whose correlation between the signal intensity and the excitation wavelength is smaller than the reference value, the signal component corresponding to the ambient light can be attenuated accurately. Thereby, the light observation device according to the present aspect is not limited to limited conditions such as a dark room, and can be used, for example, for component analysis of an object located in a space illuminated by indoor illumination light. Thus, according to this aspect, it is possible to provide a highly versatile light observation apparatus. In addition, since the accuracy of the fluorescence observation is enhanced, the analysis accuracy of the component of the object can also be enhanced.

Also, for example, the first light receiving unit receives the first light at a plurality of observation wavelengths different from one another, and the signal processing circuit performs the plurality of excitations on each of the plurality of observation wavelengths. The signal strength of the first output signal corresponding to the first excitation wavelength selected from the wavelengths and the signal strength of the first output signal corresponding to the second excitation wavelength selected from the plurality of excitation wavelengths Calculating a difference absolute value of the signal component, and the signal component at the observation wavelength corresponding to the difference absolute value, the signal component being a signal component included in the first output signal when the The first output signal may be attenuated as the first signal component.

As a result, a component having a small correlation between the signal intensity and the excitation wavelength can be appropriately determined, so that the signal component corresponding to the ambient light can be attenuated accurately. Therefore, since the accuracy of fluorescence observation is enhanced, the analysis accuracy of the component of the object can also be enhanced.

Also, for example, when the excitation light is not irradiated to the object, the first light receiving unit further receives the second light incident on the first light receiving unit, and A second output signal representing the light reception intensity for each observed wavelength of the light of No. 2; and the signal processing circuit generates a signal component corresponding to the ambient light from the first output signal to the second output signal It may be attenuated as

As a result, since light is received when excitation light is not emitted and almost no fluorescence is generated, the received light substantially becomes a component resulting from ambient light. Therefore, since the light reception intensity | strength of environmental light can be acquired accurately, the precision of fluorescence observation can be raised and the analysis precision of the component of a target object can also be raised.

Also, for example, the signal processing circuit may further specify the component included in the object based on the signal strength of the first output signal in which the first signal component is attenuated.

This allows component analysis of the object. For this reason, since the light observation apparatus according to this aspect can grasp what substance is present at the place, it is possible to promptly take measures according to the substance. For example, when a virus is detected, the virus can be rapidly cleaned and can be used for the prevention of infection and the like.

Also, for example, the first light receiving unit receives the first light at a plurality of observation wavelengths different from one another, and the signal processing circuit outputs the first output in which the first signal component is attenuated. The component included in the object may be identified by evaluating the signal strength of the signal for each combination of the plurality of excitation wavelengths and the plurality of observation wavelengths.

Thereby, component analysis of the object can be performed with high accuracy based on so-called fluorescent fingerprints.

Also, for example, the light observation apparatus according to one aspect or the other aspect of the present disclosure may further include a light source that emits the irradiation light toward the target.

Thereby, since the light observation device includes the light source, the irradiation light of the intensity sufficient to generate at least one light selected from the group consisting of the reflected light returned from the object and the fluorescence generated from the object is targeted It is possible to irradiate the object. Therefore, the light observation apparatus according to the present aspect can be used, for example, for component analysis of an object even if there is no light source that emits illumination light around the object, and the versatility is extremely high.

Also, for example, the ambient light may be indoor illumination light.

Thus, for example, at least one light selected from the group consisting of reflected light returned from an object and fluorescence generated from an object even in a room illuminated with illumination light such as a LED (Light Emitting Diode) or a fluorescent lamp It can be observed. For this reason, the light observation apparatus according to this aspect can be used for component analysis of not only an object disposed in a dark room or a measuring apparatus but also an object present in daily living space, for example. Extremely high.

Specifically, the light observation device can be used to confirm the position of a virus or fungus existing in a room by using a virus or fungus as an example of the object. The light observation device can detect, for example, attached norovirus when a person infected with the norovirus touches the doorknob or the table.

Also, for example, the object may be human vomit.

For example, when a person vomits on the floor, a part of the vomiting material is scattered, and it can not be confirmed with the naked eye to which range it splattered. When vomits that can not be cleaned up remain, there is a risk that viruses etc. will multiply. According to the light observation apparatus according to this aspect, for example, since the fluorescence of the organic substance contained in the remaining vomit can be observed, it is possible to confirm the position of part of the scattered vomit. Moreover, when the light observation apparatus according to this aspect is used after cleaning the vomiting substance, it is possible to confirm that the vomiting substance remains. Therefore, the effect of cleaning can be confirmed.

Also, for example, the object may be fine particles scattered in a space.

Thereby, fine particles such as pollen or dust can be detected.

In the light observation method according to one aspect of the present disclosure, when at least a part of the object is irradiated with the irradiation light, the light observation method includes the reflected light returned from the at least a part and the fluorescence generated from the at least a part Obtaining a first output signal representing the received light intensity of the first light including at least one light selected from the group and the ambient light; and receiving the received light intensity of the second light including the ambient light Attenuating a first signal component corresponding to the ambient light from the first output signal by obtaining a second output signal representing the signal and calculating the first output signal and the second output signal And b.

Thus, it is possible to realize a highly versatile light observation method as in the light observation device described above.

In the fluorescence observation method according to one aspect of the present disclosure, fluorescence generated from the target when environment is irradiated with irradiation light having excitation wavelengths selected from a plurality of different excitation wavelengths, and environment Obtaining a first output signal representing the intensity of the first light including light; and a signal component included in the first output signal, wherein the signal intensity of the signal component is correlated with the excitation wavelength Attenuating a signal component smaller than a reference value from the first output signal as a first signal component corresponding to the ambient light.

Thus, it is possible to realize a highly versatile light observation method as in the light observation device described above.

Further, a program according to an aspect of the present disclosure is a program executed by a computer, and when at least a part of the target is irradiated with the irradiation light in the first light receiving unit, the at least a part The first light including at least one light selected from the group consisting of the reflected light that has returned and the fluorescence generated from the at least a part, and the ambient light is received, and the received light intensity of the first light is represented Outputting the first output signal; and causing the second light receiving unit to receive the second light including the ambient light and outputting a second output signal representing the received light intensity of the second light And attenuating a first signal component corresponding to the ambient light from the first output signal by computing the first output signal and the second output signal in the signal processing circuit. Including.

In addition, a program according to another aspect of the present disclosure is a program executed by a computer, and an irradiation light having an excitation wavelength selected from a plurality of different excitation wavelengths is an object in the first light receiving unit. And a step of causing the first light including the fluorescence and the ambient light generated from the object to be received, and outputting a first output signal representing the received light intensity of the first light, and a signal In the processing circuit, the signal processing circuit is a signal component included in the first output signal, and the ambient light is a signal component whose correlation between the signal intensity of the signal component and the excitation wavelength is smaller than a reference value. And Attenuating from the first output signal as a first signal component corresponding to

Further, a computer readable recording medium according to an aspect of the present disclosure is a computer readable recording medium storing a program, and when the program is executed by the computer, the first light receiving unit includes: At least one light selected from the group consisting of the reflected light returned from the at least one part and the fluorescence generated from the at least one when the irradiation light is irradiated to at least one part of the object, and the ambient light , And outputting a first output signal representing the received light intensity of the first light, and receiving a second light including the ambient light in a second light receiving unit Outputting a second output signal representing the received light intensity of the second light, and the signal processing circuit calculating the first output signal and the second output signal. A step of the first output signal attenuating a first signal component corresponding to the ambient light, is executed.

A computer readable recording medium according to another aspect of the present disclosure is a computer readable recording medium storing a program, wherein the first light receiving unit when the program is executed by the computer. The first light including the fluorescent light generated from the target and the ambient light when the target is irradiated with illumination light having an excitation wavelength selected from a plurality of different excitation wavelengths, Outputting a first output signal representing the received light intensity of the first light, and the signal processing circuit including a signal component included in the first output signal, the signal intensity of the signal component and the excitation wavelength Attenuating from the first output signal a signal component whose correlation with is smaller than a reference value as a first signal component corresponding to the ambient light.

In the present disclosure, all or part of a circuit, unit, device, member or part, or all or part of a functional block in a block diagram represents a semiconductor device, a semiconductor integrated circuit (IC), or a large scale integration (LSI). It may be implemented by one or more electronic circuits, including: The LSI or IC may be integrated on one chip or may be configured by combining a plurality of chips. For example, functional blocks other than storage elements may be integrated on one chip. Although the term “LSI” or “IC” is used here, the term is changed depending on the degree of integration, and may be called system LSI, VLSI (very large scale integration), or ULSI (ultra large scale integration). A Field Programmable Gate Array (FPGA) programmed after the manufacture of the LSI, or a reconfigurable logic device capable of reconfiguring junctions inside the LSI or setting up circuit sections inside the LSI can also be used for the same purpose.

Furthermore, all or part of the functions or operations of the circuits, units, devices, members or parts can be performed by software processing. In this case, the software is recorded on a non-transitory recording medium such as one or more ROMs, optical disks, hard disk drives, etc., and the software is identified by the software when it is executed by a processor. The functions are performed by a processor and peripherals. System or apparatus, one or more non-transitory recording medium software has been recorded, the processing device (processor), and The required hardware devices, for example interface may comprise a.

Embodiments will be specifically described below with reference to the drawings.

Note that all the embodiments described below show general or specific examples. Numerical values, shapes, materials, components, arrangement positions and connection forms of components, steps, order of steps, and the like shown in the following embodiments are merely examples, and are not intended to limit the present disclosure. Further, among the components in the following embodiments, components not described in the independent claim indicating the highest concept are described as arbitrary components.

Further, each drawing is a schematic view, and is not necessarily illustrated exactly. Therefore, for example, the scale and the like do not necessarily match in each figure. Further, in each of the drawings, substantially the same configuration is given the same reference numeral, and overlapping description will be omitted or simplified.

Embodiment 1
[1-1. Overview]
First, an outline of the light observation apparatus according to the first embodiment will be described with reference to FIG. FIG. 1 is a block diagram showing a configuration of a light observation apparatus 10 according to the present embodiment.

The light observation device 10 receives light including at least one light selected from the group consisting of reflected light returned from the object 11 and fluorescence generated from the object 11 when the object 11 is irradiated with irradiation light. And detecting the object 11 based on the intensity of the at least one light included in the received light. Specifically, the light observation device 10 is a fluorescence observation device, and as shown in FIG. 1, the first light 14 containing fluorescence generated from the object 11 when the object 11 is irradiated with the excitation light 13. Is received, and a fluorescent fingerprint is generated based on the intensity of the fluorescence contained in the received first light 14 (hereinafter referred to as observation light). The light observation device 10 further performs component analysis of the object 11 based on the fluorescent fingerprint.

In the present embodiment, ambient light 12 is irradiated to the object 11. For this reason, the observation light includes not only fluorescence but also ambient light 12. Therefore, the light observation device 10 according to the present embodiment attenuates the signal component corresponding to the environmental light 12 from the output signal representing the light reception intensity of the observation light received by the first light reception unit 30 to obtain a fluorescence component. Generates a signal corresponding to The light observation device 10 generates a fluorescent fingerprint based on the signal in which the signal component corresponding to the ambient light 12 is attenuated.

The ambient light 12 is, for example, indoor illumination light. The indoor illumination light is specifically white light emitted from a fluorescent lamp or an LED lamp.

The object 11 is, for example, a human vomit. The vomit contains an organic substance that emits fluorescence when irradiated with the excitation light 13. Examples of the organic substance include, but are not limited to, tryptophan, tyrosine, vitamin A, vitamin B2, and NADH (nicotinamide adenine dinucleotide).

Tryptophan generates fluorescence having a peak at 310 nm when irradiated with excitation light 13 having an excitation wavelength of 280 nm. Furthermore, tryptophan produces fluorescence having a peak at 310 nm even when the excitation light 13 having an excitation wavelength of 270 nm is irradiated.

Tyrosine generates fluorescence having a peak at 300 nm when the excitation light 13 having an excitation wavelength of 275 nm is irradiated. Vitamin A generates fluorescence having a peak at 425 nm when irradiated with excitation light 13 whose excitation wavelength is 325 nm. Vitamin B2 generates fluorescence having a peak at 520 nm when the excitation light 13 having an excitation wavelength of 450 nm is irradiated. NADH generates fluorescence having a peak at 460 nm when the excitation light 13 having an excitation wavelength of 350 nm is irradiated.

The object 11 may be fine particles scattered in the space. Specifically, the object 11 may be organic matter such as pollen scattered in space or house dust. For example, by irradiating excitation light 13 to a protein that constitutes pollen, the protein is excited to generate fluorescence.

Thus, the combination of the effective excitation wavelength and the wavelength of the fluorescence by the excitation light 13 having the excitation wavelength is determined for each substance. Therefore, the light observation device 10 can specify the component of the object 11 by specifying the combination of the wavelength of the emitted excitation light 13 (that is, the excitation wavelength) and the wavelength of the observed fluorescence. .

[1-2. Constitution]
Next, the configuration of the light observation apparatus 10 will be described with reference to FIGS. 1 and 2. FIG. 2 is a diagram showing a specific configuration of the light source unit 20 and the first light receiving unit 30 of the light observation device 10 according to the present embodiment.

As shown in FIGS. 1 and 2, the light observation device 10 includes a light source unit 20, a first light receiving unit 30, and a signal processing circuit 40. The signal processing circuit 40 is not shown in FIG.

[1-2-1. Light source section]
The light source unit 20 is an example of a light source that irradiates the irradiation light toward the object 11. The light source unit 20 irradiates the target object 11 with excitation light 13 which is an example of irradiation light. In the present embodiment, the light source unit 20 irradiates the object 11 with a plurality of excitation lights 13 having different excitation wavelengths. Specifically, as shown in FIG. 2, the light source unit 20 includes a plurality of excitation light sources 21, a plurality of filters 22, a plurality of optical fibers 23, and a light emitting lens 24.

Each of the plurality of excitation light sources 21 is a light source that emits light (for example, white light) having a wide wavelength band. Each of the plurality of excitation light sources 21 is, for example, a discharge lamp such as a halogen lamp or a solid light emitting element such as an LED, but is not limited thereto.

The plurality of filters 22 are provided in one-to-one correspondence with the plurality of excitation light sources 21. Each of the plurality of filters 22 is provided in an optical path formed by an optical fiber 23 connecting the corresponding excitation light source 21 and the light emission lens 24.

Each of the plurality of filters 22 is a band pass filter having a corresponding excitation wavelength as a central wavelength. The bandwidth of each of the plurality of filters 22 is, for example, 10 nm or more and 50 nm or less. The pass bands of each of the plurality of filters 22 do not overlap each other, for example. Each of the plurality of filters 22 passes light of the corresponding excitation wavelength among the light emitted from the corresponding excitation light source 21.

For example, the light source unit 20 includes six excitation light sources 21 and six filters 22 respectively corresponding to six excitation wavelengths. The six excitation wavelengths are, for example, 270 nm, 275 nm, 280 nm, 325 nm, 350 nm and 450 nm. These wavelengths are wavelengths selected in advance according to the type of the object 11. Here, an effective excitation wavelength is used as the excitation light 13 for tryptophan, tyrosine, vitamin A, vitamin B2 and NADH described above, but the invention is not limited thereto. The number of excitation light sources 21 included in the light source unit 20 is not limited to six, and may be two, ten, or a large number of ten or more.

The plurality of optical fibers 23 are provided, for example, in one-to-one correspondence with the plurality of excitation light sources 21. The plurality of optical fibers 23 respectively connect the corresponding excitation light source 21 and the light emission lens 24 to form an optical path for guiding the excitation light 13 emitted from the excitation light source 21 to the light emission lens 24.

The light emitting lens 24 is a light transmitting lens for emitting the excitation light 13 toward the object 11.

The light source unit 20 may include only one excitation light source 21 emitting an excitation wavelength having a sufficient intensity in a wide range including a plurality of excitation wavelengths. In this case, by switching the plurality of filters 22 for each excitation wavelength, the light source unit 20 can irradiate the object 11 with the excitation light 13 for each excitation wavelength. Moreover, the light source part 20 may be provided with the several excitation light source 21 which radiate | emits the light which has a peak in a mutually different wavelength.

The light source unit 20 may irradiate the excitation light 13 to the object 11 while continuously changing the excitation wavelength. For example, the light source unit 20 may sequentially irradiate the object 11 with a plurality of excitation lights 13 having different excitation wavelengths while changing the excitation wavelength in steps of 10 nm in a range of 220 nm to 550 nm.

Further, the configuration of the light source unit 20 shown in FIG. 2 is merely an example, and the light source unit 20 may not include the optical fiber 23 and the light emitting lens 24.

1-2-2. First light receiving unit]
The first light receiving unit 30 is at least one selected from the group consisting of reflected light returned from the object 11 and fluorescence generated from the object 11 when the irradiation light from the light source unit 20 is irradiated to the object 11. It receives a first light 14 including one light and an ambient light 12 and outputs a first output signal representing the received light intensity of the first light 14. In the present embodiment, the irradiation light is excitation light 13 having an excitation wavelength selected from a plurality of different excitation wavelengths. At least one light included in the first light 14 is fluorescence generated from the object 11 by being excited by the irradiation light. That is, in the present embodiment, the observation light which is the first light 14 includes the fluorescence generated from the object 11 and the ambient light 12.

Specifically, the first light receiving unit 30 is excited by the excitation light 13 and emits fluorescence emitted from the object 11 when the excitation light 13 having the excitation wavelength selected from a plurality of different excitation wavelengths is irradiated. And outputs a first output signal representing the received light intensity for each observed wavelength of the first light 14. As described above, the first light 14 includes not only fluorescence but also ambient light 12. Further, since the environmental light 12 is irradiated to the object 11, the first light 14 includes the environmental light 12 reflected by the object 11.

In the present embodiment, the first output signal includes a plurality of output signals for each excitation wavelength. That is, the first light receiving unit 30 outputs an output signal corresponding to each of the plurality of excitation wavelengths. The signal intensity of the output signal for each excitation wavelength represents the light reception intensity for each observation wavelength.

As shown in FIG. 2, the first light receiving unit 30 includes a plurality of light detectors 31, a plurality of filters 32, a plurality of optical fibers 33, and a light receiving lens 34.

Each of the plurality of photodetectors 31 receives light from the object 11 and outputs an electrical signal representing the intensity of the received light. Specifically, each of the plurality of photodetectors 31 is a photoelectric conversion element such as a photodiode. Each of the plurality of photodetectors 31 receives the light that has passed through the corresponding filter 32, and thus outputs a signal representing the light reception intensity for each wavelength of the light transmitted by the filter 32.

The plurality of filters 32 are provided in one-to-one correspondence with the plurality of photodetectors 31. Each of the plurality of filters 32 is a band pass filter having a bandwidth of 10 nm or more and 50 nm or less, each having a different wavelength as a central wavelength. The transmission bands of each of the plurality of filters 32 do not overlap each other, for example.

For example, the first light receiving unit 30 includes five light detectors 31 and five filters 32. The wavelengths of light transmitted by each of the five filters 32 (that is, the observation wavelengths) are, for example, 300 nm, 310 nm, 425 nm, 460 nm, and 520 nm. These wavelengths are wavelengths selected in advance according to the type of the object 11. Here, although the wavelength of fluorescence emitted by tryptophan, tyrosine, vitamin A, vitamin B2 and NADH described above is used, the present invention is not limited thereto. The number of photodetectors 31 and filters 32 provided in the first light receiving unit 30 is not limited to five, and may be two, ten, or a large number of ten or more.

The plurality of optical fibers 33 are provided in one-to-one correspondence with the plurality of light detectors 31. Each of the plurality of optical fibers 33 connects the corresponding photodetector 31 and the light receiving lens 34, and guides the light (that is, observation light) incident on the light receiving lens 34 to each of the plurality of light detectors 31. It is formed.

The light receiving lens 34 is a light transmitting lens on which the light reached from the object 11 is incident.

The first light receiving unit 30 may include only one photodetector 31 having sufficient sensitivity in a wide range including a plurality of observation wavelengths. In this case, for example, the photodetector 31 sequentially receives the light of each observation wavelength by sequentially functioning the plurality of filters 32 (specifically, sequentially transmitting the observation light to the plurality of optical fibers 33) be able to.

For example, the first light receiving unit 30 may receive the observation light while continuously changing the wavelength to be received. For example, the first light receiving unit 30 may receive observation light while changing the target wavelength in steps of 1 nm in a range of 230 nm to 700 nm. Thereby, the first light receiving unit 30 can generate and output the first output signal with high wavelength resolution.

The configuration of the first light receiving unit 30 illustrated in FIG. 2 is merely an example, and the first light receiving unit 30 may not include the optical fiber 33 and the light receiving lens 34.

[1-2-3. Signal processing circuit]
The signal processing circuit 40 processes the first output signal output from the first light receiving unit 30. The signal processing circuit 40 is realized by, for example, an integrated circuit including a processor and the like.

Specifically, as shown in FIG. 1, the signal processing circuit 40 includes an attenuation unit 41, an evaluation unit 42, and a specifying unit 43.

The attenuator 41 attenuates, from the first output signal, a signal component that is included in the first output signal and whose correlation between the signal intensity of the signal component and the excitation wavelength is smaller than the reference value. Specifically, a signal component that is included in the first output signal and whose correlation between the signal intensity of the signal component and the excitation wavelength is smaller than the reference value is a signal component corresponding to the ambient light 12 . That is, the attenuator 41 attenuates the signal component corresponding to the ambient light 12 from the first output signal to generate a signal in which the signal component corresponding to the ambient light 12 is attenuated.

Specifically, for each observation wavelength, the attenuation unit 41 corresponds to the signal intensity corresponding to the first excitation wavelength selected from the plurality of excitation wavelengths and the second excitation wavelength selected from the plurality of excitation wavelengths. The difference absolute value with the signal strength to be calculated is calculated. Furthermore, when the calculated difference absolute value is equal to or less than the threshold, the attenuation unit 41 attenuates the signal component at the observation wavelength corresponding to the difference absolute value.

For example, the attenuation unit 41 attenuates the intensity of the signal component at the observation wavelength corresponding to the difference absolute value which is equal to or less than the threshold value to 1/10. The degree of attenuation is not limited to this, and may be 1/2 to 1/100. Furthermore, the attenuation unit 41 may set the intensity of the signal component at the wavelength to be attenuated to zero.

The evaluation unit 42 evaluates the signal strength of the first output signal whose signal component is attenuated for each combination of the excitation wavelength and the observation wavelength. Specifically, the evaluation unit 42 generates a fluorescent fingerprint based on the signal in which the signal component corresponding to the ambient light 12 is attenuated.

FIG. 3 is a view showing an example of an ideal fluorescent fingerprint when there is no ambient light 12. The fluorescent fingerprint is three-dimensional data represented by signal intensity (specifically, intensity of fluorescence) with respect to a combination of the wavelength of excitation light 13 and the wavelength of observation light (specifically, fluorescence).

In FIG. 3, the vertical axis indicates the wavelength of the excitation light 13 (that is, the excitation wavelength), and the horizontal axis indicates the coordinates of the same signal intensity continuously in two-dimensional coordinates indicating the wavelength of the observation light (that is, the observation wavelength). Fig. 6 illustrates connecting isointensity lines. Further, in FIG. 3, the area where the signal intensity is the highest is indicated by hatching of dots. Although not clearly represented in FIG. 3, the example shown in the same figure shows an example of a fluorescent fingerprint having a large signal intensity when the excitation wavelength is 280 nm and the observation wavelength is 340 nm. . Moreover, FIG. 3 has shown the result of having observed all of excitation wavelength and observation wavelength by 5 nm intervals.

As shown in FIG. 3, the fluorescence emitted from the object 11 has wavelength dependence (that is, excitation wavelength dependence) to the excitation light 13.

The identifying unit 43 identifies the component of the object 11 based on the signal strength of the first output signal obtained by attenuating the signal component. Specifically, the specifying unit 43 specifies the component of the object 11 based on the signal strength for each combination of the excitation wavelength and the observation wavelength. The identifying unit 43 identifies the substance included in the object 11 by referring to the correspondence table between the substance and the wavelength.

The correspondence table is, for example, a combination of an effective excitation wavelength and a wavelength of fluorescence emitted when the excitation light 13 having the excitation wavelength is irradiated to a plurality of substances such as an organic substance (hereinafter referred to as a fluorescence wavelength). Are associated. For example, when the substance is tryptophan, it is correlated that the excitation wavelengths are 270 nm and 280 nm, and the fluorescence wavelength is 310 nm. The same applies to tyrosine, vitamin A, vitamin B2 and NADH, and other organic substances.

Although the correspondence table is stored in a memory or the like included in the specifying unit 43, the present invention is not limited to this. The correspondence table may be stored, for example, in another device such as a server device, and the identification unit 43 may refer to the correspondence table by communicating with the other device.

In the present embodiment, the specifying unit 43 specifies, for example, a combination having a large signal intensity among a plurality of combinations of the excitation wavelength and the observation wavelength based on the fluorescent fingerprint. For example, the identifying unit 43 identifies the combination of the excitation wavelength and the observation wavelength at which the signal intensity is maximum in the fluorescent fingerprint, and refers to the correspondence table based on the identified combination to thereby select the substance corresponding to the identified combination. Identify. For example, when the combination of the excitation wavelength and the observation wavelength that maximizes the signal intensity is 270 nm and 280 nm and the fluorescence wavelength is 310 nm, the identification unit 43 includes tryptophan in the object 11. Identify what you The result specified by the identification unit 43 is output to the outside together with, for example, the fluorescent fingerprint.

[1-3. Operation]
Subsequently, the operation of the light observation device 10 according to the present embodiment will be described with reference to FIG. FIG. 4 is a flowchart showing the operation of the light observation device 10 according to the present embodiment.

Here, as the object 11, a human vomit will be described as an example. For example, when a sick person or a care recipient vomits in a hospital or a nursing home or the like, the staff wipes off the vomiting material. After that, the presence or absence of the remaining vomit is detected by using the light observation device 10 according to the present embodiment with the area where the wiping is performed and the vicinity thereof as a range.

In hospitals or nursing homes, lighting devices such as fluorescent lights are installed. The light emitted from the lighting device is emitted as environmental light 12 to the area where the vomit was wiped off and the vicinity thereof.

FIG. 5 is a view showing an example of the spectrum of the ambient light 12. Specifically, FIG. 5 shows the spectrum of white light emitted from a fluorescent lamp. As shown in FIG. 5, the ambient light 12 contains a wavelength component in the visible light band, and has a peak at a predetermined wavelength. In the example illustrated in FIG. 5, the wavelengths of the peaks included in the ambient light 12 (that is, peak wavelengths) are 400 nm, 430 nm, 480 nm, 540 nm, and 610 nm.

As shown in FIG. 4, first, the light source unit 20 irradiates the object 11 with the excitation light 13 (S10). Specifically, the light source unit 20 sequentially illuminates the plurality of excitation lights 13 having different excitation wavelengths onto the object 11 by sequentially turning on the plurality of excitation light sources 21. For example, the excitation light 13 is irradiated to the object 11 in the order of 270 nm, 275 nm, 280 nm, 325 nm, 350 nm, and 450 nm.

The first light receiving unit 30 receives the light from the object 11 each time the excitation light 13 having different excitation wavelength is irradiated, and generates an output signal representing the received light intensity of the received light (S12). That is, the first light receiving unit 30 generates an output signal for each excitation wavelength.

Specifically, when the excitation light 13 of one excitation wavelength (for example, 270 nm) is received, all the photodetectors 31 receive observation light emitted from the object 11 for each observation wavelength. Each of the photodetectors 31 performs photoelectric conversion of the received light to generate an output signal representing the light reception intensity of the observation wavelength. By putting together the output signals from the light detector 31, an output signal representing the light reception intensity for each observation wavelength with respect to the irradiated excitation light 13 is obtained. The first light receiving unit 30 generates an output signal each time the excitation light 13 is irradiated, thereby generating an output signal for each excitation wavelength and outputting the output signal to the signal processing circuit 40. Thereby, the first light receiving unit 30 outputs a first output signal including an output signal for each excitation wavelength.

FIG. 6 is a view showing an example of a fluorescent fingerprint based on an output signal output from the first light receiving unit 30 of the light observation device 10 according to the present embodiment. In FIG. 6, the vertical axis indicates the excitation wavelength, and the horizontal axis indicates the isointensity lines that continuously connect the coordinates having the same signal intensity in two-dimensional coordinates indicating the observation wavelength. Further, in FIG. 6, the area where the signal strength is the highest is indicated by hatching of dots.

FIG. 7 is a diagram showing an output signal output from the first light receiving unit 30 of the light observation device 10 according to the present embodiment. In FIG. 7, the horizontal axis indicates the observation wavelength, and the vertical axis indicates the signal strength of the output signal. Each of a plurality of graphs in FIG. 7 shows an output signal for each excitation wavelength. Here, the excitation wavelength is 10 types of wavelengths selected in 10 nm steps from the range of 220 nm or more and 310 nm or less.

Specifically, in FIG. 7, the graph with the lowest signal strength at the observation wavelength of 350 nm is the output signal with the excitation wavelength of 220 nm, and the graph with the highest signal strength is the output signal with the excitation wavelength of 310 nm. is there. The excitation wavelength increases in this order from the graph with the lowest signal intensity to the highest graph at an observation wavelength of 350 nm.

6 and FIG. 7 show the same first output signal except for the illustrated method.

As can be seen from FIG. 6, when the observation wavelengths are 430 nm, 480 nm, 540 nm and 610 nm, regions of vertical streaks with high signal strength are generated. That is, when the observation wavelengths are 430 nm, 480 nm, 540 nm and 610 nm, it means that observation light of high intensity is received regardless of the excitation wavelength. These observation wavelengths correspond to the peak wavelength of the ambient light 12 shown in FIG.

Also in FIG. 7, the signal intensity is increased regardless of the excitation wavelength at the peak wavelength of the ambient light 12, specifically, 430 nm, 480 nm, 540 nm and 610 nm. That is, the ambient light 12 has no excitation wavelength dependency. By attenuating the component of the ambient light 12, the fluorescence intensity from the object 11 can be acquired.

Returning to FIG. 4, in the present embodiment, the attenuator 41 of the signal processing circuit 40 attenuates the signal component of the ambient light 12 from the first output signal (S14). Specifically, the attenuation unit 41 first selects arbitrary two excitation wavelengths from a plurality of excitation wavelengths of the excitation light 13 irradiated to the object 11. Here, as an example, the attenuation unit 41 selects 240 nm as the first excitation wavelength and 270 nm as the second excitation wavelength.

Next, the attenuation unit 41 calculates, for each observation wavelength, the difference absolute value between the signal strength of the output signal corresponding to the selected first excitation wavelength and the signal strength of the output signal corresponding to the selected second excitation wavelength. Calculate Furthermore, the attenuation unit 41 determines, for each observation wavelength, whether the calculated difference absolute value is equal to or less than a predetermined threshold.

The attenuation unit 41 estimates that the observation wavelength at which the absolute difference value is equal to or less than the threshold is a wavelength component included in the ambient light 12, and attenuates the signal component at the observation wavelength. In the example shown in FIG. 6 and FIG. 7, the attenuator 41 attenuates the signal components having observation wavelengths of 430 nm, 480 nm, 540 nm and 610 nm. For example, the attenuation unit 41 reduces the signal strength of the first output signal to 1/10 at observation wavelengths of 430 nm, 480 nm, 540 nm, and 610 nm. Specifically, the attenuation unit 41 reduces the signal strength of each of the output signals for each excitation wavelength constituting the first output signal to 1/10. A signal obtained by attenuating the signal component corresponding to the ambient light 12 is shown in FIG. 8 and FIG.

FIG. 8 is a view showing an example of a fluorescent fingerprint based on a signal generated by the signal processing circuit 40 of the light observation apparatus 10 according to the present embodiment and having the signal component corresponding to the ambient light 12 attenuated. FIG. 9 is a diagram showing a signal generated by the signal processing circuit 40 of the light observation device 10 according to the present embodiment, in which the signal component corresponding to the ambient light 12 is attenuated. 8 and 9 correspond to FIGS. 6 and 7, respectively.

The signals shown in FIGS. 8 and 9 are signal components corresponding to the ambient light 12, that is, signals from which the signal components having no excitation wavelength dependency have been removed from the first output signal. As can be seen by comparing FIG. 4, FIG. 6 and FIG. 8, the fluorescent fingerprint generated based on the signal in which the signal component corresponding to the ambient light 12 is attenuated has the same excitation as the fluorescent fingerprint shown in FIG. The dependency between the wavelength and the observed wavelength is more clearly identified than the fluorescent fingerprint shown in FIG. Therefore, the component of the object 11 can be identified by using the fluorescent fingerprint. The fluorescent fingerprint shown in FIG. 8 is generated by the evaluation unit 42.

Returning to FIG. 4, in the present embodiment, the identification unit 43 of the signal processing circuit 40 identifies the component of the object 11 based on the signal in which the signal component corresponding to the ambient light 12 is attenuated (S16). Specifically, the identification unit 43 identifies the combination of the excitation wavelength and the observation wavelength with high signal strength based on the fluorescent fingerprint generated from the signal in which the signal component corresponding to the ambient light 12 is attenuated. By referring to the table, the substance corresponding to the combination is identified.

As described above, according to the light observation device 10 according to the present embodiment, a signal component corresponding to the ambient light 12 is selected from the first output signal based on the light from the object 11 irradiated with the ambient light 12. Attenuate. The fluorescent fingerprint generated based on the signal in which the signal component corresponding to the ambient light 12 is attenuated is fluorescence similar to the fluorescent fingerprint generated based on the light from the object 11 to which the ambient light 12 is not irradiated. The excitation wavelength dependency of is confirmed. Therefore, the component of the object 11 can be identified with high accuracy based on the fluorescent fingerprint generated based on the signal in which the signal component corresponding to the ambient light 12 is attenuated.

Thus, the light observation device 10 according to the present embodiment can specify the component of the object 11 even when the object 11 is irradiated with the ambient light 12. Therefore, according to the present embodiment, it is possible to provide the light observation device 10 with high versatility.

Second Embodiment
Subsequently, the second embodiment will be described.

The light observation apparatus according to the second embodiment is different from the light observation apparatus 10 according to the first embodiment in the method of attenuating the first output signal. Specifically, in the present embodiment, the ambient light 12 is a second output signal representing the light receiving intensity for each observed wavelength of the second light incident on the light receiving unit when the excitation light 13 is not irradiated. Attenuate the first output signal as a corresponding signal component.

[2-1. Constitution]
First, the configuration of the light observation apparatus according to the present embodiment will be described with reference to FIG. FIG. 10 is a block diagram showing a configuration of the light observation device 110 according to the present embodiment.

As shown in FIG. 10, the light observation device 110 includes a light source unit 120, a first light receiving unit 130, and a signal processing circuit 140. The light source unit 120, the first light receiving unit 130, and the signal processing circuit 140 correspond to the light source unit 20, the first light receiving unit 30, and the signal processing circuit 40 according to the first embodiment, respectively. In the following, differences from the first embodiment will be mainly described, and the description of the common points will be omitted or simplified.

The light source unit 120 can switch on / off of the irradiation of the excitation light 13 to the object 11. Specifically, the light source unit 120 switches on / off of the irradiation of the excitation light 13 based on an external input such as a user operation and a light reception result by the first light receiver 130. The light source unit 120 is connected to, for example, a controller that switches on / off of the irradiation of the excitation light 13.

For example, when the light source unit 120 receives an operation to start fluorescence observation from the user, the light source unit 120 emits the excitation light 13, and the first light receiving unit 130 outputs the first output signal, and then emits the excitation light 13. Stop. Alternatively, the light source unit 120 may start the irradiation of the excitation light 13 after the first light receiving unit 130 outputs the second output signal when the user receives an operation to start fluorescence observation. .

The first light receiving unit 130 receives the second light incident on the first light receiving unit 130 when the excitation light 13 is not irradiated to the object 11, and the second light is observed for each observation wavelength of the second light. A second output signal representing the received light intensity is output. The second light does not include the fluorescence emitted from the object 11 due to the irradiation of the excitation light 13.

The signal processing circuit 140 includes an attenuation unit 141 instead of the attenuation unit 41. The attenuator 141 attenuates the first output signal to the second output signal as signal components corresponding to the ambient light 12. Specifically, the attenuation unit 141 attenuates the signal component corresponding to the environmental light 12 by subtracting the signal intensity of the second output signal from the signal intensity of the first output signal for each observation wavelength. Generate a signal.

[2-2. Operation]
Subsequently, the operation of the light observation device 110 according to the present embodiment will be described using FIG. FIG. 11 is a flowchart showing the operation of the light observation device 110 according to the present embodiment.

As shown in FIG. 11, the irradiation of the excitation light 13 (S10) and the acquisition of the first output signal (S12) are the same as the processing shown in FIG. Specifically, the signal processing circuit 40 obtains the first output signal shown in FIGS. 6 and 7.

Next, the light source unit 120 stops the irradiation of the excitation light 13 (S23). Specifically, the light source unit 120 stops the emission of the excitation light 13 after the first light receiving unit 130 outputs the first output signal. The first output signal is stored, for example, in a storage unit (not shown) or the like included in the signal processing circuit 140.

Next, the first light receiving unit 130 receives the light (that is, the second light) from the object 11, and outputs a second output signal representing the light receiving intensity for each observation wavelength of the light (S24). .

FIG. 12 is a view showing an example of a fluorescent fingerprint based on light received by the first light receiving unit 130 of the light observation apparatus 110 according to the present embodiment when the excitation light 13 is not irradiated to the object 11. is there. In addition, FIG. 12 is not what was actually measured but is created by simulation. Therefore, the spectrum of the ambient light 12 shown in FIG. 5 is strictly different.

As shown in FIG. 12, in the wavelength band corresponding to the peak wavelength of the ambient light 12, vertical streaks with large signal strength can be seen. In the fluorescent fingerprint shown in FIG. 12, since the excitation light 13 is not irradiated to the object 11, the component depending on the excitation wavelength is not included.

Next, the attenuator 141 attenuates the first output signal to the second output signal as a signal component corresponding to the ambient light 12 (S25). Specifically, since the fluorescent fingerprint shown in FIG. 12 is removed from the fluorescent fingerprint shown in FIG. 6, a signal corresponding to the fluorescent fingerprint shown in FIG. 8 is generated.

Finally, the identifying unit 43 identifies the component of the object 11 based on the signal in which the signal component corresponding to the ambient light 12 is attenuated (S16). The specific process is the same as that of the first embodiment.

As described above, according to the optical observation device 110 according to the present embodiment, there is no need to specify a signal component having no excitation wavelength dependency, and the second output signal is simply subtracted from the first output signal. By doing this, a signal component corresponding to the ambient light 12 is attenuated. Therefore, the amount of processing related to signal processing can be reduced.

In addition, since light is received when little fluorescence is generated from the object 11 without being irradiated with the excitation light 13, most of the received light is a component caused by the ambient light 12. Therefore, since the light observation apparatus 110 can acquire the light reception intensity | strength of the environmental light 12 precisely, the precision of fluorescence observation can be raised and the analysis precision of a target object can also be raised.

Third Embodiment
Subsequently, the third embodiment will be described.

The light observation apparatus according to the third embodiment differs from the light observation apparatus 110 according to the second embodiment in the method of generating the second output signal. Specifically, in the present embodiment, the light observation apparatus includes a second light receiving unit that generates and outputs a second output signal.

FIG. 13 is a block diagram showing a configuration of the light observation device 210 according to the present embodiment.

As shown in FIG. 13, the light observation device 210 includes a light source unit 20 and a signal processing circuit 240 instead of the light source unit 120 and the signal processing circuit 140 as compared to the light observation device 110 according to the second embodiment. And the second light receiving unit 230 is newly provided. In the following, differences from the second embodiment will be mainly described, and the description of the common points will be omitted or simplified.

The second light receiving unit 230 is provided at a position not overlapping the optical path of the fluorescence generated by the object 11. For example, the second light receiving unit 230 is disposed such that the light receiving surface of the first light receiving unit 30 and the light receiving surface of the second light receiving unit 230 face in different directions. Specifically, for example, the light receiving surface of the first light receiving unit 30 is disposed on the first surface of the housing of the light observation apparatus 210, and the second surface on the second surface facing the first surface is used. The light receiving surface of the light receiving unit 230 is disposed. By providing the second light receiving unit 230 in this manner, the fluorescence generated in the object 11 does not enter the second light receiving unit 230.

The second light receiving unit 230 receives the second light 15 corresponding to the ambient light 12 and outputs a second output signal representing the light receiving intensity of the second light 15. In the present embodiment, the second light receiving unit 230 receives the second light 15 and outputs a second output signal representing the light reception intensity of the second light 15 for each observed wavelength. Specifically, the second light receiving unit 230 is a component of the environmental light 12 that is reflected by a region different from the region irradiated with the irradiation light emitted from the light source unit 20 and the environmental light 12. And a component directly incident on the second light receiving unit 230 are received as the second light 15. The configuration of the second light receiving unit 230 is, for example, the same as that of the first light receiving unit 30 shown in FIG.

The first light receiving unit 30 and the second light receiving unit 230 may be different portions in one light receiving device. For example, the light observation device 210 may include an image sensor including the first light receiving unit 30 and the second light receiving unit 230.

For example, the light observation device 211 illustrated in FIG. 14 includes the image sensor 250 including the first light receiving unit 30 and the second light receiving unit 230. FIG. 14 is a block diagram showing a configuration of a light observation apparatus 211 according to a modification of the third embodiment.

The image sensor 250 is an image sensor having a light receiving area in which a plurality of pixels are arranged. In this case, the first light receiving unit 30 and the second light receiving unit 230 are respectively different areas in the light receiving area. Specifically, for example, in the light receiving area of the image sensor 250, the distance between the first area corresponding to the first light receiving unit 30 and the second area corresponding to the second light receiving unit 230 is the object 11 Larger than the spot size of the fluorescence generated by.

The second light 15 hardly contains the excitation light 13 and the fluorescence excited by the excitation light 13 but contains the ambient light 12. Therefore, the second output signal is considered to be equivalent to the second output signal in the second embodiment.

The signal processing circuit 240 includes an attenuation unit 241 instead of the attenuation unit 141. The attenuation unit 241 attenuates the signal component corresponding to the ambient light 12 from the first output signal by calculation of the first output signal and the second output signal. Specifically, the attenuation unit 241 attenuates the first output signal to the second output signal as a signal component corresponding to the ambient light 12. More specifically, the attenuation unit 241 attenuates the signal component corresponding to the environmental light 12 by subtracting the signal intensity of the second output signal from the signal intensity of the first output signal for each observation wavelength. Generate a signal.

As described above, since the light observation device 210 according to the present embodiment includes the second light receiving unit 230, while the first light receiving unit 30 receives light including fluorescence from the object 11 at the same time, The second light receiving unit 230 can receive light containing no fluorescence by the excitation light 13. For example, since the second light receiving unit 230 can be used exclusively for receiving the ambient light 12, the light receiving intensity of the ambient light 12 can be accurately obtained without being affected by disturbance light such as fluorescence. Therefore, the accuracy of the fluorescence observation is enhanced, so that the analysis accuracy of the component of the object 11 can also be enhanced.

Embodiment 4
Subsequently, the fourth embodiment will be described.

The light observation apparatus according to the fourth embodiment is different from the light observation apparatus according to the first to third embodiments in an object to be detected. Further, in the light observation apparatus according to the present embodiment, not the fluorescence emitted by the object but the reflected light (specifically, the backscattered light) from the object is received.

[4-1. Constitution]
FIG. 15 is a block diagram showing a configuration of the light observation device 310 according to the present embodiment. FIG. 16 is a diagram schematically showing the principle of the light observation device 310 according to the present embodiment.

As shown in FIG. 15, the light observation device 310 is different from the light observation device 210 according to the third embodiment in the light source unit 320 instead of the light source unit 20, the first light receiving unit 30, and the signal processing circuit 240. , And the first light receiving unit 330 and the signal processing circuit 340 are different. In the following, differences from the third embodiment will be mainly described, and the description of the common points will be omitted or simplified.

In the present embodiment, the object 311 is a fine particle that does not emit fluorescence among the fine particles (so-called aerosol) scattered in the space. For example, the object 311 is a particulate matter such as PM 2.5 or PM 10, yellow sand, or dust. The target object 311 is, for example, an inorganic substance containing no organic substance, but may be an organic substance such as pollen. As schematically shown in FIG. 16, the object 311 is localized and floated within a range of, for example, 50 cm 3.

The light source unit 320 is an example of a light source that emits the irradiation light 16 toward the object 311. The irradiation light 16 emitted from the light source unit 320 does not have to excite the object 311, and thus light of a wavelength selected from a wide wavelength band can be used. For example, the light source unit 320 includes a laser diode or an LED having a wavelength in the range of 300 nm to 1400 nm. The wavelength of the light source unit 320 is, for example, near infrared light or infrared light of 780 nm or more. For example, a laser diode or LED emits pulsed light.

The light source unit 320 may include, for example, the light emitting lens 24 as in the first embodiment. The light emitting lens 24 is, for example, a collimating lens. The light emitted from the laser diode or the LED is converted into parallel light by the light emitting lens 24, and is output as the irradiation light 16.

In the first light receiving unit 330, when the irradiation light 16 from the light source unit 320 is irradiated to the object 311, the reflected light in which at least a part of the irradiation light 16 is reflected by the object 311, and the environmental light 12 , And outputs a first output signal representing the received light intensity of the first light 14. Specifically, in the present embodiment, the reflected light is backscattered light by Mie scattering from the object 311. For the first light receiver 330, for example, a photodiode or a photomultiplier tube (PMT) can be used.

In the present embodiment, since the irradiation light 16 is not wavelength-converted by the object 311, the wavelength of the reflected light and the wavelength of the irradiation light 16 are substantially the same. For this reason, the observation wavelength by the first light receiving unit 330 is, for example, the same as the wavelength of the irradiation light 16 emitted by the light source unit 320.

For example, as shown in FIG. 16, the first light receiving unit 330 is provided at a 90 ° side position with respect to the emission direction of the irradiation light 16 from the light source unit 320. A half mirror 332 is provided on the path of the irradiation light 16. The half mirror 332 transmits the irradiation light 16 emitted from the light source unit 320 and reflects the reflection light from the object 311. The reflected light thus reflected is received by the first light receiver 330.

As in the third embodiment, the second light receiving unit 230 receives the second light 15 corresponding to the ambient light 12 and outputs a second output signal representing the light receiving intensity of the second light 15. Do. For example, the second light receiving unit 230 is provided so that the light receiving range does not overlap with the first light receiving unit 330.

The signal processing circuit 340 does not include the evaluation unit 42 and the identification unit 43, and includes an attenuation unit 341. The attenuator 341 attenuates the signal component corresponding to the ambient light 12 from the first output signal by calculation of the first output signal and the second output signal. For example, the attenuator 341 attenuates the first output signal to the second output signal as a signal component corresponding to the ambient light 12.

[4-2. Operation]
Subsequently, the operation of the light observation device 310 according to the present embodiment will be described using FIGS. 16 to 19.

In the present embodiment, first, the light source unit 320 emits the irradiation light 16. As shown in FIG. 16, when the object 311 is present, at least a part of the irradiation light 16 emitted from the light source unit 320 is reflected by the object 311. At this time, light reflected backward, that is, backscattered light 382 is reflected by the half mirror 332 and received by the first light receiving unit 330.

In addition, the rest of the irradiation light 16 emitted from the light source unit 320 is reflected by the wall surface 390 or the like. The reflected light 392 is also received by the first light receiver 330 in the same manner as the backscattered light 382.

FIG. 17 is a diagram showing a time change of a signal output from the first light receiving unit 330 of the light observation device 310 according to the present embodiment. In FIG. 17, the horizontal axis indicates the elapsed time from the point of time when the irradiation light 16 which is pulse light is emitted. The vertical axis represents the signal strength of the first output signal output from the first light receiving unit 330. The same applies to FIGS. 18 and 19 described later.

As shown in FIG. 17, after the irradiation light 16 is emitted, a peak 384 corresponding to the backscattered light 382 appears. The time when the peak 384 appears corresponds to the distance from the light source unit 320 and the first light receiving unit 330 to the object 311. The size of peak 384 corresponds, for example, to the size or concentration of particles of object 311.

Since ambient light 12 also enters the first light receiving unit 330, the first output signal includes a signal component corresponding to the ambient light 12 as shown in FIG. As shown in FIG. 18, when the intensity of the ambient light 12 varies, as shown in FIG. 17, it becomes difficult to detect the peak 384 mixed with the variation of the intensity of the ambient light 12.

Here, FIG. 18 is a diagram showing a time change of a signal output from the second light receiving unit 230 of the light observation device 310 according to the present embodiment. In the second light receiving unit 230, none of the irradiation light 16, the back scattered light 382 and the reflected light 392 is received, and the ambient light 12 around the light observation device 310 is received. Therefore, the second output signal output from the second light receiving unit 230 corresponds to a signal component corresponding to the ambient light 12.

In the present embodiment, the attenuator 341 of the signal processing circuit 340 attenuates the signal component corresponding to the ambient light 12 from the first output signal shown in FIG. Specifically, the attenuation unit 341 attenuates the second output signal shown in FIG. 18 from the first output signal shown in FIG. This generates the signal shown in FIG.

FIG. 19 is a diagram showing a signal generated by the signal processing circuit 340 of the light observation device 310 according to the present embodiment, from which the signal component corresponding to the ambient light 12 is attenuated from the first output signal. As shown in FIG. 19, since the signal component corresponding to the ambient light 12 is attenuated, it is possible to detect the peak 384 corresponding to the back scattered light 382 which is the reflected light from the object 311 with high accuracy. The signal processing circuit 340 specifies the type and position of the object 311 based on, for example, the time and size of the peak 384.

In addition, after the peak 384 appears, a peak 394 corresponding to the reflected light 392 by the wall surface 390 appears. The time at which the peak 394 appears corresponds to the distance from the light source unit 320 and the first light receiving unit 330 to the wall surface 390. The magnitude of peak 394 is greater than the magnitude of peak 384.

When the object 311 is not present, the peak 394 appears without the peak 384 appearing. Thus, it can be seen that the object 311 does not exist between the light source unit 320 and the wall surface 390.

In the present embodiment, the light source unit 320 may emit the excitation light 13 as the irradiation light. In this case, when the object 311 is an organic substance, the fluorescence is received by the first light receiver 330. When the object 311 is an inorganic substance that does not emit fluorescence, the backscattered light by Mie scattering is received by the first light receiving unit 330. Since the wavelengths are different between the fluorescence and the backscattered light, the wavelength separation by the first light receiving unit 330 makes it possible to determine which wavelength component light is received. Thereby, it can be determined whether the object 311 is an organic substance or an inorganic substance.

(Other embodiments)
As mentioned above, although the light observation device concerning one or a plurality of modes was explained based on an embodiment, this indication is not limited to these embodiments. As long as various modifications that can occur to those skilled in the art are made to the present embodiment, and forms configured by combining components in different embodiments are included within the scope of the present disclosure, without departing from the gist of the present disclosure. Be

For example, the light detector 31 may be an image sensor in which pixels, which are a plurality of photoelectric conversion elements, are arranged in a matrix. Thereby, since two-dimensional fluorescence observation can be performed, component analysis of a plurality of objects 11 present in a predetermined region can be performed simultaneously. Specifically, since a fluorescent fingerprint is obtained for each pixel of the image sensor, component analysis of the object 11 can be performed for each pixel.

In addition, for example, the light observation device 10 may not include the light source unit 20. For example, another excitation light source may irradiate the excitation light 13 to the object 11, and the light observation device 10 may receive fluorescence generated by the excitation light 13 irradiated to the object 11. Alternatively, the light observation device 10 may use a wavelength component included in the ambient light 12 as the excitation light 13.

In addition, for example, the signal processing circuit 40 of the light observation device 10 may not include the specifying unit 43. For example, the signal processing circuit 40 may be provided with an output terminal for outputting fluorescence fingerprint data, a communication interface, or the like, instead of the identification unit 43. The signal processing circuit 40 may output the fluorescent fingerprint data to the server device.

Also, for example, in the above-described embodiment, although the example in which the object 11 is human vomit, pollen, house dust, or the like has been described, the present invention is not limited thereto. The object 11 is not particularly limited as long as it contains a substance that emits fluorescence when irradiated with the excitation light 13. In addition, as described in the fourth embodiment, the object 11 may be an object that does not emit fluorescence.

Also, for example, the present disclosure can be realized as a light observation method including, as a step, processing performed by the signal processing circuit of the light observation apparatus according to each embodiment.

For example, in the light observation method, first, the signal processing circuit generates fluorescence from the object 11 when the object 11 is irradiated with excitation light 13 having excitation wavelengths selected from a plurality of different excitation wavelengths, and A first output signal representing the intensity of each of the plurality of observation wavelengths of the first light 14 including the ambient light 12 is obtained (Step S12 in FIG. 4). Next, the signal processing circuit attenuates the signal component corresponding to the environmental light 12 from the acquired first output signal, and attenuates the signal intensity of the first output signal corresponding to the environmental light 12, Evaluation is performed for each combination of excitation wavelength and observation wavelength (step S14 in FIG. 4). Further, the signal processing circuit may specify the component of the object 11 based on the signal obtained by attenuating the signal component corresponding to the ambient light 12 (step S16 in FIG. 4).

In another light observation method, first, the signal processing circuit is composed of the reflected light returned from the object 11 and the fluorescence generated from the object 11 when the irradiation light from the light source is irradiated to the object 11. A first output signal representing the received light intensity of the first light 14 including at least one light selected from the group and the ambient light 12 is obtained (step S12 in FIG. 11). Next, the signal processing circuit obtains a second output signal representing the received light intensity of the second light 15 including the ambient light 12 (step S24 in FIG. 11). The acquisition of the first output signal and the acquisition of the second output signal may be performed simultaneously, or either may be performed first. Next, the signal processing circuit attenuates the signal component corresponding to the ambient light 12 from the first output signal by calculation of the first output signal and the second output signal (step S25 in FIG. 11).

The present disclosure can not only be realized as a light observation method, but also as a program for causing a computer to execute each step included in the light observation method, and a recording medium such as a DVD (Digital Versatile Disc) recording the program. It can also be realized. Each step described above is realized by the computer reading and executing the program stored in the recording medium. The program may be pre-recorded on the recording medium, or may be supplied to the recording medium via a wide area communication network including the Internet.

In each of the above embodiments, each component of the signal processing circuit of the light observation apparatus may be configured by dedicated hardware, or realized by executing a software program suitable for each component. It may be done. Each component may be realized by a program execution unit such as a central processing unit (CPU) or processor reading and executing a software program recorded in a recording medium such as a hard disk or a semiconductor memory.

At this time, the type of processor is not limited as long as the function can be realized by executing a program. For example, the processor is configured of one or more electronic circuits including a semiconductor integrated circuit such as an integrated circuit (IC) or a large scale integration (LSI). The plurality of electronic circuits may be integrated on one chip or may be provided on a plurality of chips. The plurality of chips may be integrated into one device or may be distributed and provided to a plurality of devices.

As described above, the above-described general or specific aspects may be realized by a system, an apparatus, an integrated circuit, a computer program, or a computer readable recording medium, and the system, the apparatus, the integrated circuit, the computer program, and the recording It may be realized by any combination of media.

Further, various modifications, replacements, additions, omissions and the like can be made in the above-described embodiments within the scope of the claims or the equivalents thereof.

The present disclosure can be used as a highly versatile light observation device, and can be used, for example, as an analysis device of an object.

10, 110, 210, 211, 310 Light observation device 11, 311 Object 12 Environment light 13 Excitation light 14 First light 15 Second light 16 Irradiation light 20, 120, 320 Light source part 21 Excitation light source 22, 32 Filter 23, 33 optical fiber 24 light emitting lens 30, 130, 330 first light receiving unit 31 light detector 34 light receiving lens 40, 140, 240, 340 signal processing circuit 41, 141, 241, 341 attenuation unit 42 evaluation unit 43 identification Part 230 Second light receiving part 250 Image sensor 332 Half mirror 382 Backscattered light 384, 394 Peak 390 Wall 392 Reflected light

Claims (20)

1. At least one light selected from the group consisting of the reflected light returned from the at least one part and the fluorescence generated from the at least one when the irradiation light is irradiated to at least one part of the object, and the ambient light And a first light receiving unit that receives a first light including the first light and outputs a first output signal representing a light reception intensity of the first light.
   A second light reception provided at a position not overlapping the optical path of the at least one light, receiving a second light including the ambient light, and outputting a second output signal representing a light receiving intensity of the second light Department,
   A signal processing circuit;
   The signal processing circuit attenuates a first signal component corresponding to the ambient light from the first output signal by calculation of the first output signal and the second output signal.
   Light observation device.
2. The illumination light has an excitation wavelength selected from a plurality of different excitation wavelengths,
   The first light includes the fluorescence
   The light observation device according to claim 1.
3. The first light includes the reflected light,
   The light observation device according to claim 1.
4. Each of the first light receiving unit and the second light receiving unit includes a plurality of pixels,
   The first light receiving unit and the second light receiving unit constitute an image sensor.
   The light observation device according to claim 1.
5. The signal processing circuit further includes
   The component included in the object is identified based on the signal strength of the first output signal in which the first signal component is attenuated.
   The light observation device according to claim 2.
6. The first light receiving unit receives the first light at a plurality of different observation wavelengths.
   The signal processing circuit evaluates the signal strength of the first output signal, in which the first signal component is attenuated, for each combination of the plurality of excitation wavelengths and the plurality of observation wavelengths, to thereby obtain the object. Identify the components contained in
   The light observation device according to claim 5.
7. And a light source for irradiating the irradiation light toward the object.
   The light observation device according to claim 1.
8. The ambient light is indoor illumination light,
   The light observation device according to claim 1.
9. The object is a human vomit.
   The light observation device according to claim 1.
10. The object is a fine particle scattering in space,
    The light observation device according to claim 1.
11. When the object is irradiated with illumination light having an excitation wavelength selected from a plurality of different excitation wavelengths, the first light including the fluorescence and the ambient light generated from the object is received, and the first light is emitted. A first light receiving unit that outputs a first output signal representing the light receiving intensity of the light;
    A signal processing circuit;
    The signal processing circuit is a signal component included in the first output signal, and a signal component whose correlation between the signal intensity of the signal component and the excitation wavelength is smaller than a reference value corresponds to the ambient light. Attenuate the first output signal as a one signal component,
    Light observation device.
12. The first light receiving unit receives the first light at a plurality of different observation wavelengths.
    The signal processing circuit
    For each of the plurality of observation wavelengths, a signal strength of the first output signal corresponding to a first excitation wavelength selected from the plurality of excitation wavelengths and a second selected from the plurality of excitation wavelengths Calculating a difference absolute value from the signal intensity of the first output signal corresponding to the excitation wavelength;
    A signal component at an observation wavelength corresponding to the difference absolute value, which is a signal component included in the first output signal when the difference absolute value is equal to or less than a threshold, is the first signal component. Attenuate from the first output signal,
    The light observation device according to claim 11.
13. The signal processing circuit further includes
    The component included in the object is identified based on the signal strength of the first output signal in which the first signal component is attenuated.
    The light observation device according to claim 11.
14. The first light receiving unit receives the first light at a plurality of different observation wavelengths.
    The signal processing circuit evaluates the signal strength of the first output signal, in which the first signal component is attenuated, for each combination of the plurality of excitation wavelengths and the plurality of observation wavelengths, to thereby obtain the object. Identify the components contained in
    The light observation device according to claim 13.
15. And a light source for irradiating the irradiation light toward the object.
    The light observation device according to claim 11.
16. The ambient light is indoor illumination light,
    The light observation device according to claim 11.
17. The object is a human vomit.
    The light observation device according to claim 11.
18. The object is a fine particle scattering in space,
    The light observation device according to claim 11.
19. A computer readable recording medium storing a program, comprising:
    When the program is executed by the computer
    At least one selected from the group consisting of the reflected light returned from the at least one portion and the fluorescence generated from the at least one portion when at least a portion of the object is irradiated with the irradiation light in the first light receiving portion Receiving a first light comprising one light and an ambient light, and outputting a first output signal representing the received light intensity of the first light;
    Causing the second light receiving unit to receive the second light including the ambient light and outputting a second output signal representing the light receiving intensity of the second light;
    Attenuating a first signal component corresponding to the ambient light from the first output signal by computing the first output signal and the second output signal in the signal processing circuit;
    A computer readable recording medium on which is executed.
20. A computer readable recording medium storing a program, comprising:
    When the program is executed by the computer
    The first light including the fluorescence generated from the target and the ambient light when the target is irradiated with the irradiation light having the excitation wavelength selected from the plurality of different excitation wavelengths in the first light receiving unit. Outputting a first output signal representing the received light intensity of the first light;
    A signal processing circuit, a signal component included in the first output signal, the signal component whose correlation between the signal intensity of the signal component and the excitation wavelength is smaller than a reference value corresponds to the ambient light; Attenuating from said first output signal as a signal component of
    A computer readable recording medium on which is executed.

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