WO2023233561A1

WO2023233561A1 - Optically integrated spectroscopic sensor, measurement system, and measurement method

Info

Publication number: WO2023233561A1
Application number: PCT/JP2022/022240
Authority: WO
Inventors: 彰裕藤江; 裕之河野; 康人橋場; 浩志大塚; 俊行安藤
Original assignee: 三菱電機株式会社
Priority date: 2022-06-01
Filing date: 2022-06-01
Publication date: 2023-12-07
Also published as: JPWO2023233561A1

Abstract

This optically integrated spectroscopic sensor comprises: a sensor chip that is provided with a light-emitting unit (101; 101A) having at least one light source which emits a light beam, and a light-receiving unit (102; 102A) having at least one light-receiving element which receives scattered reflection light of the emitted light beam; and a light-blocking unit (13) that is disposed on the surface of the sensor chip, that has at least one window (12) which transmits the emitted light beam and the scattered reflection light, and that blocks light around the at least one window.

Description

Optical integrated spectroscopic sensor, measurement system, and measurement method

The present disclosure relates to optical sensing technology.

In recent years, techniques for non-destructively measuring the state of a test object or chemically analyzing a reagent have become widespread. For example, Patent Document 1 describes a sensor that non-destructively performs chemical analysis of a test object. This sensor includes a light source, a grating waveguide, and a light receiving section. Multi-wavelength light such as white light outputted from a light source is coupled to a grating waveguide via a spatial optical system, and is guided within the grating waveguide while undergoing repeated total reflection. Evanescent light generated in the process of total reflection is absorbed by the test object according to the characteristics of the test object, and the output light from the grating waveguide is output to the light receiving section via the spatial optical system.

Special Publication No. 06-502012

When measuring by placing the sensor described in Patent Document 1 in close contact with the object to be inspected, there is a problem that stray light in addition to the measurement light enters the light receiving section because the distance between the sensor and the object to be inspected is short.

The present disclosure has been made based on the recognition of the above-mentioned problems, and one aspect of the present disclosure aims to provide an optical integrated spectroscopic sensor that can suppress stray light.

An optical integrated spectroscopic sensor according to an aspect of an embodiment of the present disclosure includes a light emitting section having at least one light source that emits a light beam, and a light receiving section having at least one light receiving element that receives scattered reflected light of the emitted light beam. a light shielding section provided on the surface of the sensor chip, having at least one window that transmits the emitted light beam and the scattered reflected light, and shielding light around the at least one window; Equipped with.

According to the optical integrated spectroscopic sensor according to one aspect of the embodiment of the present disclosure, stray light can be suppressed.

1 is a configuration diagram showing an optical integrated spectroscopic sensor and a measurement system according to Embodiment 1. FIG. 3 is a configuration diagram showing an example of an internal structure of a light receiving section according to Embodiment 1. FIG. 3 is a flowchart showing the flow of measurement according to Embodiment 1. FIG. 3 is a flowchart showing the operation of the optical integrated spectroscopic sensor according to the first embodiment. 3 is a flowchart showing a measurement method according to Embodiment 1. FIG. 3 is a graph showing the relationship between the wavelength and light intensity of an optical signal before and after placement of an inspection target according to Embodiment 1. FIG. 1 is a diagram showing an example of how to use the optical integrated spectroscopic sensor according to Embodiment 1. FIG. 1 is a diagram showing an example of how to use the optical integrated spectroscopic sensor according to Embodiment 1. FIG. FIG. 2 is a configuration diagram showing an optical integrated spectroscopic sensor and a measurement system according to a second embodiment. FIG. 7 is a diagram showing a modification of the multiplexing waveguide according to the second embodiment. FIG. 7 is a configuration diagram showing a modification of the optical integrated spectroscopic sensor according to the second embodiment.

Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Note that components given the same or similar symbols in the drawings have the same or similar configurations or functions, and overlapping explanations of such components will be omitted.

Embodiment 1.
<Configuration>
An integrated optical spectroscopic sensor, a measurement system, and a measurement method according to Embodiment 1 of the present disclosure will be described with reference to FIGS. 1 to 8. FIG. 1 is a configuration diagram showing an optical integrated spectroscopic sensor and a measurement system according to the first embodiment. As shown in FIG. 1, the measurement system includes an optical integrated spectroscopic sensor 1 and an analysis device 4, and uses the measurement system to optically measure an object 3 to be inspected. The optical integrated spectroscopic sensor 1 is used to optically measure the internal or surface state of the inspection object 3, and the optical integrated spectroscopic sensor 1 transmits the measurement results to the analysis device 4. At the time of measurement, the optical integrated spectroscopic sensor 1 is placed close to the inspection object 3, for example, via the thin film sheet 2, and the measurement is performed. That is, by bringing the optical integrated spectroscopic sensor 1 and the thin film sheet 2 into close contact, and by bringing the thin film sheet 2 and the test object 3 into close contact, the optical integrated spectroscopic sensor 1 and the test object 3 are placed close to each other.

(Target for inspection)
The inspection object 3 is an object to be optically measured using the optical integrated spectroscopic sensor 1, and examples of the inspection object 3 include solids and powders made of materials that emit scattered reflected light by scattering or reflection. More specific examples of the inspection object 3 include food, building walls, metal objects, and turbine blades. As the state of the inspection object 3, for example, the state such as temperature, water concentration, or pressure is measured.

(Thin film sheet)
The thin film sheet 2 is a flat, thin insulating sheet made of polyethylene, for example. In the following description, the thin film sheet 2 is assumed to be a thin and soft member that can be placed over the inspection object 3, but the thin film sheet 2 may be a rigid plate-shaped member. The thin film sheet 2 is made of, for example, a material that transmits light having the wavelength emitted from the light emitting section 101.

(Optical integrated spectroscopic sensor)
The optical integrated spectroscopic sensor 1 is an optical sensor that optically measures the internal state of the inspection object 3. The optical integrated spectroscopic sensor 1 includes a sensor chip 1C and a light shielding section 13 provided on the surface of the sensor chip 1C. The light shielding part 13 has a window 12. The sensor chip 1C includes a substrate 10, optical or electrical elements provided on the substrate 10, and all or part of a protective layer 11 for protecting the elements on the substrate 10. The light shielding section 13 having the substrate 10, the mold section 11, and the window section 12 is configured as one package. The optical integrated spectroscopic sensor 1 converts a measurement result indicating the state of the inspection object 3 into a wireless signal and transmits the wireless signal.

(substrate)
The substrate 10 is a substrate on which a light emitting section 101, a light receiving section 102, a wireless signal converter 103, and a power source 104 are mounted. All or part of the light emitting section 101, the light receiving section 102, the wireless signal converter 103, and the power source 104 may be integrated, and a chip obtained by the integration may be mounted on the substrate 10. Elements such as the light emitting section 101 may be mounted on the substrate 10 by forming all or part of the section 102, the wireless signal converter 103, and the power source 104 on the substrate 10 using silicon photonics technology. A light emitting unit 101 on the substrate 10 emits a light beam for acquiring information on the inspection object 3, a light receiving section 102 on the substrate 10 receives the scattered reflected light from the inspection object 3, and a wireless signal conversion on the substrate 10 is performed. The device 103 generates a wireless signal to be transmitted to the analysis device 4. Further, a wireless signal converter 103 on the substrate 10 receives a power supply signal from the analysis device 4, and a power supply 104 on the substrate 10 supplies power for driving the optical integrated spectroscopic sensor 1.

(protective layer)
The protective layer 11 is a member for protecting components or elements mounted on the substrate 10, and is formed on the substrate 10. The protective layer 11 is formed of, for example, a resin molding material. In the following description, it is assumed that the protective layer 11 is a mold layer formed of a resin mold resin, but the protective layer 11 does not need to be a mold layer. Since the protective layer 11 only needs to be able to transmit light having the wavelength emitted from the light emitting section 101, the protective layer 11 may be formed of, for example, a transparent plate. By providing the protective layer 11, components or elements placed on the substrate 10 can be protected. Further, by providing the protective layer 11, the optical path length from the light emitting section 101 to the light receiving section 102 can be kept constant without being affected by the surrounding environment.

(light shielding part)
The light shielding part 13 is a light shielding part that blocks light rays. The light shielding part 13 is formed with a window 12 that transmits light rays, and among the light rays traveling from the light emitting part 101 to the light shielding part 13 , the light rays directed toward the window 12 are transmitted through the window 12 , and the light rays directed to the window 12 pass through the window 12 . Light rays directed toward the part are blocked. Further, scattered reflected light from the inspection object 3 passes through the window 12, and stray light unnecessary for measurement is blocked. Examples of stray light include stray light that occurs between the light shielding section 13 and the substrate 10 on which the light emitting section 101 is mounted, and stray light that occurs between the light shielding section 13 and the inspection object 3. In this way, the light shielding section 13 is a light shielding section that has the window 12 that transmits the light rays emitted from the light emitting section 101 and the scattered reflected light, and blocks light around the window 12. The light-shielding portion 13 can be formed, for example, by printing a light-shielding ink having light-shielding properties such as black ink on the surface of the protective layer 11 (the surface opposite to the substrate 10). As another example, the light shielding part 13 may be a plate-like member in which the window 12 is formed. As yet another example, the light shielding portion 13 may be formed of a film or masking tape having light shielding properties. Further, a light shielding portion 13 may be formed on the side surface of the protective layer 11. The window 12 is an opening formed in the light shielding part 13 and has a finite opening diameter or opening width. The size of the aperture is formed to be larger than the beam diameter of the light beam in order to transmit the light beam, but the upper limit of the size depends on the specific application. The shape of the window 12 may be any shape, for example, round, square, or slit. A transparent plate may be fitted into the opening formed in the window 12. By providing such a light shielding part 13, stray light unnecessary for measurement can be suppressed.

(light emitting part)
The light emitting unit 101 is a light emitting unit having at least one light source that emits a light beam. The light emitting unit 101 is arranged so that the light beam emitted from the light emitting unit 101 is directed toward the window 12. A laser light source or an LED light source can be used as the light source. The number of emission wavelengths may be a single wavelength or multiple wavelengths. However, the emission wavelength needs to include a wavelength that has characteristic optical properties such as reflection or absorption with respect to the information (for example, water content) of the inspection object 3 that is desired to be acquired. For example, when acquiring the amount of moisture contained inside the inspection object 3, the emission wavelength from the light emitting section 101 needs to include the 1450 nm band, which is the absorption wavelength of moisture. In the following description, it is assumed that the light emitting unit 101 emits light beams with multiple wavelengths, and that the optical integrated spectroscopic sensor 1 acquires information regarding a plurality of items related to internal information of the inspection object 3.

(Light receiving section)
The light receiving section 102 is a light receiving section having at least one light receiving element that receives scattered reflected light. The light receiving section 102 includes a grating waveguide 1021, a linear waveguide 1022, a wavelength selective switch 1023, and a photoelectric conversion section 1024. The grating waveguide 1021 receives scattered reflected light that is measurement light, and couples the received scattered reflected light to the linear waveguide 1022 as received light. The linear waveguide 1022 guides the received light to the wavelength selective switch 1023. The wavelength selective switch 1023 switches the optical path of the received light for each wavelength and separates the received light into optical signals for each wavelength. The photoelectric conversion unit 1024 converts optical signals of each wavelength into electrical signals.

(Grating waveguide)
The grating waveguide 1021 is a waveguide in which a diffraction grating is formed. The grating waveguide 1021 has a function of diffracting measurement light having different arrival angles for each wavelength and coupling it to the linear waveguide 1022. Diffraction gratings with a plurality of types of grating periods are formed in the grating waveguide 1021 according to the number of wavelengths of measurement light. When the measurement light has a single wavelength, the grating period may be uniform.

(linear waveguide)
The linear waveguide 1022 is a linear waveguide that propagates the received light from the grating waveguide 1021 to the wavelength selective switch 1023.

(wavelength selection switch)
The wavelength selective switch 1023 is a waveguide that has the function of switching paths for each wavelength. The path is switched for each wavelength in accordance with the operating wavelength of the photoelectric conversion unit 1024. FIG. 2 is an example of a waveguide configuration of the wavelength selective switch 1023. For example, it is possible to arrange ring resonators for the number of wavelengths and switch the optical path depending on the resonance wavelength of the ring resonators. In the example of FIG. 2, the wavelength selective switch 1023 includes three ring resonators in order to separate optical signals of three mutually different wavelengths λ ₁ , λ ₂ , and λ ₃ . The wavelength selective switch 1023 branches the received light into a plurality of optical signals with different wavelengths by switching paths, and guides the branched optical signal to the photoelectric conversion unit 1024 .

(Photoelectric conversion section)
The photoelectric conversion unit 1024 converts the received optical signal into an electrical signal, and outputs the converted electrical signal to the wireless signal converter 103. The photoelectric conversion unit 1024 is a light receiving element, and is realized by a photodiode. In order to receive the entire wavelength range of the optical signal to be analyzed, a plurality of photoelectric conversion units 1024 may be arranged, or a single photoelectric conversion unit 1024 that operates in a wide band may be arranged.

(Wireless signal converter)
The wireless signal converter 103 converts the electrical signal output from the photoelectric conversion unit 1024 into a wireless signal, and transmits the wireless signal to the analysis device 4.

(Analysis device)
The analysis device 4 is a device that receives a wireless signal transmitted from the optical integrated spectroscopic sensor 1, analyzes the received wireless signal, and displays the analysis result of the test object 3 to the user. The analysis device 4 is a device that generates a power supply signal for the optical integrated spectroscopic sensor 1, converts it into a wireless signal in the wireless signal converter 405, and then transmits the power supply signal to the optical integrated spectroscopic sensor 1. . In order to realize these functions, the analysis device 4 includes a wireless signal converter 401 that receives a wireless signal transmitted from the optical integrated spectroscopic sensor 1 and converts the wireless signal into an electrical signal, and an output from the wireless signal converter 401. The present invention includes an analysis unit 402 that analyzes the generated electrical signal, a display device 403 that displays the analysis results, a power supply unit 404 that generates a power supply signal, and a wireless signal converter 405 that converts the generated power supply signal into a wireless signal. The analysis unit 402 is realized by a dedicated processing circuit or by a combination of a memory that stores a program and a processor that reads and executes the program stored in the memory.

(Wireless signal converter)
The radio signal converter 401 of the analysis device 4 converts the radio signal transmitted from the radio signal converter 103 into an electrical signal, and transmits the electrical signal to the analysis unit 402.

(Analysis Department)
The analysis unit 402 analyzes the signal characteristics of the received signal, such as intensity, phase, and frequency, received by the optical integrated spectroscopic sensor 1, and specifies the internal state of the inspection object 3. FIG. 6 is a graph showing the relationship between the wavelength and intensity of the optical signal before and after placement of the inspection object 3 according to the first embodiment. For example, the analysis unit 402 can identify the internal information of the inspection object 3 by detecting a change in the intensity of the received signal before and after the inspection object is placed. FIG. 6 shows that the light intensity at wavelengths λ ₁ , λ ₂ , λ _N-1 , and λ _N decreases after placing the test object 3 than before placing the test object 3. There is.

(display device)
The display device 403 is a display that displays the analysis results by the analysis unit 402.

(Power supply part)
The power supply unit 404 is a power supply that generates a power supply signal for driving the optical integrated spectroscopic sensor 1 .

(Wireless signal converter)
The wireless signal converter 405 converts the power feeding signal generated by the power feeding unit 404 into a wireless signal, and emits the wireless signal toward the optical integrated spectroscopic sensor 1 .

The analysis device 4 only needs to have a function of receiving and analyzing wireless signals, a function of displaying analysis results, and a function of generating and transmitting a power supply signal, and can be realized using a portable device such as a smartphone, for example. It's okay.

<Processing flow>
(signal flow)

Next, with reference to FIG. 3, the flow of measurements performed using the optical integrated spectroscopic sensor 1 and the analysis device 4 will be described. FIG. 3 is an example of a processing flow mainly for showing the flow of signals. As an example, a case will be explained in which the amount of water and the amount of protein contained inside the test object 3 are measured. Note that when performing measurements, typically, the optical integrated spectroscopic sensor 1 is placed close to the inspection object 3 via the thin film sheet 2, and the measurement is performed. The thin film sheet 2 is a sheet to ensure insulation of the optical integrated spectroscopic sensor 1, so if there is no risk of electrical conduction, the optical integrated spectroscopic sensor 1 can be placed on the inspection target 3 without using the thin film sheet 2. It may also be in direct contact.

In step S1, the light emitting unit 101 emits a light beam. In order to measure the amount of water and protein, the light emitted by the light emitting unit 101 includes a light beam with a wavelength that has an absorption characteristic (also referred to as a reflection characteristic) in water, and a beam with a wavelength that has an absorption characteristic in protein. rays of light.

The light beam emitted from the light emitting section 101 passes through the protective layer 11 and reaches the light shielding section 13 having the window 12 (Step S2).

Among the light rays that have reached the light shielding part 13, those within the aperture diameter of the window 12 are transmitted through the window 12, and the other light rays are irradiated onto the light shielding part 13, and the optical path is blocked (step S3, step S17). . When the window 12 is slit-shaped, light rays within the opening width of the slit are transmitted through the window 12.

The light beam that has passed through the window 12 passes through the thin film sheet 2 and enters the inspection object 3 (steps S4 to S5).

A light beam having a wavelength that has absorption characteristics in water is absorbed by the test object 3 in proportion to the moisture content of the test object 3, and a light beam with an intensity proportional to the moisture content of the test object 3 is emitted from the test object 3 as internally scattered light. be done. Similarly, a light beam with a wavelength that has absorption characteristics in proteins is absorbed by the test object 3 in proportion to the amount of protein in the test object 3, and a light beam with an intensity proportional to the amount of protein in the test object 3 is absorbed by the test object 3 as internally scattered light. 3 (step S6).

The internally scattered light generated in step S6 propagates in the reverse order of steps S1 to S5 and enters the grating waveguide 1021 (steps S7 to S9). Among the internally scattered lights generated in step S6, the light path of those that are not within the aperture diameter or the aperture width of the window 12 is blocked by the light shielding part 13 (step S17).

The propagation angle of the light beam incident on the grating waveguide 1021 is changed according to the incident angle and exit angle determined by the shape of the diffraction grating in the grating waveguide 1021, and the light beams of each wavelength are coupled to the same linear waveguide 1022. (Step S10).

The light beam coupled to the linear waveguide 1022 is branched into respective optical paths by the wavelength selection switch 1023 in accordance with the operating wavelength of the photoelectric conversion unit 1024, and converted into an electrical signal by the photoelectric conversion unit 1024 (step S11~ Step S12).

The electrical signal converted by the photoelectric conversion unit 1024 is converted into a wireless signal by the wireless signal converter 103 and transmitted wirelessly, and the wireless signal enters the analysis device 4 and is converted back to an electric signal by the wireless signal converter 401. (Steps S13 to S14).

The analysis unit 402 analyzes the amount of change in the intensity of the received signal, and specifies the amount of water and protein inside the test object 3 (step S15).

FIG. 6 is an example of a spectrum diagram of a received signal analyzed by the analysis section 402. For example, assuming that λ ₁ is the absorption wavelength of moisture and λ ₂ is the absorption wavelength of protein, by analyzing the intensity changes of the spectra of λ ₁ and λ ₂ before and after placing the inspection object 3, the internal The amount of water and protein contained in the product can be determined.

The display device 403 displays the analysis results indicating the internal information of the inspection object 3 to the user (step S16).

(Operation flow of optical integrated spectroscopic sensor)
Next, the operation of the optical integrated spectroscopic sensor 1 will be explained with reference to FIG. 4. Note that the assumed situation is the same as in the case of FIG.

In step T1, the light emitting unit 101 emits a light beam. This light ray includes a light ray with a wavelength that is absorbed by water and a light ray of a wavelength that is absorbed by protein.

In step T2, the grating waveguide 1021 of the light receiving unit 102 receives the internally scattered light that is the measurement light. The light received by the grating waveguide 1021 is guided to the wavelength selective switch 1023 via the linear waveguide 1022 as received light.

In step T3, the wavelength selection switch 1023 of the light receiving section 102 separates the received light according to wavelength.

In step T4, the photoelectric conversion unit 1024 of the light receiving unit 102 converts the separated optical signal into an electrical signal.

In step T5, the wireless signal converter 103 converts the electrical signal into a wireless signal and transmits the wireless signal.

(Measurement method flow)
Next, the flow of the measurement method will be explained with reference to FIG.

In step U1, a person or a robot places the optical integrated spectroscopic sensor 1 in close proximity to the inspection object 3. A thin film sheet 2 may be placed between the optical integrated spectroscopic sensor 1 and the inspection object 3. If there is no risk of electrical conduction, it is not necessary to arrange the thin film sheet 2.

In step U2, a person or a robot brings the analysis device 4 close to the optical integrated spectroscopic sensor 1 and wirelessly supplies power to operate the optical integrated spectroscopic sensor 1, and the inspection target 3 acquired by the optical integrated spectroscopic sensor 1 A signal based on the measurement light from the optical integrated spectroscopic sensor 1 is acquired using the analyzer 4.

In step U3, the acquired signal is analyzed using the analysis device 4, and the analysis result is displayed on the display device 403.

<Effect>
Embodiment 1 has the following effects compared to the conventional technology. By providing the light shielding part 13 with the window 12, the optical path of light other than the light used for measurement is blocked, so the optical path of the light used for measurement can be limited and the beam can be irradiated to a specific location without using a spatial optical system. It becomes possible to do so. Furthermore, since a spatial optical system is not used, it is possible to downsize the sensor system that transmits and receives light as the optical integrated spectroscopic sensor 1. Further, by providing the light shielding section 13, it is possible to prevent stray light unnecessary for measurement from entering the light receiving section 102. Furthermore, with conventional technology that uses evanescent light as probe light to acquire internal information of the inspection target, the interface between the optical sensor and the inspection target must satisfy total internal reflection conditions, and it is not possible to directly print a blocking section on the interface. However, in the present disclosure, since information is acquired using scattered reflected light as probe light, it becomes possible to directly print a blocking section on the boundary surface, which contributes to miniaturization of the measurement system.

<Application example>
7 and 8 are configuration diagrams showing an application example of the optical integrated spectroscopic sensor 1 according to the first embodiment. As an example, as shown in FIG. 7, the integrated optical spectroscopic sensor 1 may be placed on the food tray 6 to analyze the freshness of the food 31 accommodated on the food tray 6. Further, as another example, as shown in FIG. 8, an optical integrated spectroscopic sensor 1 may be placed on the blade 32 of the turbine to detect damage to the blade 32 of the turbine.

Embodiment 2.
<Configuration>
Next, with reference to FIGS. 9 to 11, an optical integrated spectroscopic sensor 1A and a measurement system according to a second embodiment of the present disclosure will be described. FIG. 9 is a configuration diagram showing an optical integrated spectroscopic sensor 1A and a measurement system according to the second embodiment. The optical integrated spectroscopic sensor 1A includes a sensor chip 1CA and a light shielding part 13 provided on the surface of the sensor chip 1CA. The sensor chip 1CA includes a substrate 10, optical or electrical elements provided on the substrate 10, and all or part of a protective layer 11 for protecting the elements on the substrate 10. In Embodiment 2, compared to Embodiment 1, the configuration of the light receiving section of Embodiment 1 is adopted as the configuration of the light emitting section, and the temperature is adjusted for the grating waveguide located at the output end of the light emitting section. parts are connected. With this configuration, a function of varying the emission angle of the light beam emitted from the light emitting section is provided.

The configuration according to the second embodiment shown in FIG. 9 will be explained in more detail. The thin film sheet 2, the inspection object 3, the analysis device 4, the protective layer 11, the light shielding part 13 having the window 12, the wireless signal converter 103, and the power supply 104 are the same as those in Embodiment 1; Explanation will be omitted.

The substrate 10 is a substrate on which a light emitting section 101A, a light receiving section 102A, a wireless signal converter 103, and a power source 104 are mounted. All or part of the light emitting section 101A, the light receiving section 102A, the wireless signal converter 103, and the power source 104 may be integrated, and a chip obtained by the integration may be mounted on the substrate 10. Elements such as the light emitting section 101A may be mounted on the substrate 10 by forming all or part of the section 102A, the wireless signal converter 103, and the power source 104 on the substrate 10 using silicon photonics technology. The light emitting section 101A on the substrate 10 emits a light beam for acquiring information on the inspection object 3, the light receiving section 102A on the substrate 10 receives the scattered reflected light from the inspection object 3, and the wireless signal conversion on the substrate 10 is performed. The device 103 generates a wireless signal to be transmitted to the analysis device 4. Further, a wireless signal converter 103 on the substrate 10 receives a power supply signal from the analysis device 4, and a power supply 104 on the substrate 10 supplies power for driving the optical integrated spectroscopic sensor 1A.

The light emitting unit 101A is a light emitting unit that has at least one light source that emits a light beam. The light emitting unit 101A is composed of a light source 101A1, a multiplexing waveguide 101A2, a linear waveguide 101A3, a grating waveguide 101A4, and a temperature adjustment unit 1015, and is a mechanism that generates light for acquiring information on the inspection object 3. .

The light source 101A1 is a light source that emits a light beam. A laser light source or an LED light source can be used as the light source. The number of emission wavelengths may be a single wavelength or multiple wavelengths. However, the emission wavelength needs to include a wavelength that has characteristic optical properties such as reflection or absorption with respect to the information (for example, water content) of the inspection object 3 that is desired to be acquired. For example, when acquiring the amount of moisture contained inside the inspection object 3, the emission wavelength from the light emitting section 101 needs to include the 1450 nm band, which is the absorption wavelength of moisture. The following description will be made assuming a mode in which a plurality of light sources 101A1 with single wavelength outputs having different wavelengths are arranged and a plurality of items related to internal information of the inspection object 3 are acquired.

The multiplexing waveguide 101A2 multiplexes the light emitted from a plurality of parallelly arranged single-wavelength output light sources 101A1, and propagates the multiplexed light to the linear waveguide 1033.

FIG. 10 is a diagram showing an example of a modification of the multiplexing waveguide 101A2. As shown in FIG. 10, the light source 101A1 may be placed on the substrate 10. In this case, a prism 101A6 is arranged as shown in FIG. 10, the optical path of the emitted light from the light source 101A1 is bent toward the substrate by the prism 101A6, and the emitted light is linearly guided by the coupling waveguide 101A7 formed by the grating waveguide. It may also be coupled to wavepath 1013.

The linear waveguide 101A3 is a waveguide that propagates the multiplexed light from the multiplexing waveguide 101A2 to the grating waveguide 101A4.

The grating waveguide 101A4 emits a light beam to a desired measurement location on the inspection object 3. The output angle is determined based on the shape of the diffraction grating formed in the grating waveguide 101A4. A diffraction grating is formed in the grating waveguide 101A4 so that light beams with different wavelengths are emitted toward the same window 12.

The temperature adjustment unit 1015 has a function of controlling the temperature of the grating waveguide 101A4, changing the optical constant of the diffraction grating, and changing the output angle in a desired direction. The temperature adjustment unit 1015 is realized using a Peltier element and a microcomputer, for example.

The light receiving unit 102A is a light receiving unit that has at least one light receiving element that receives scattered reflected light. Like the light receiving section 102 of Embodiment 1, the light receiving section 102A includes a grating waveguide, a linear waveguide, a wavelength selective switch, and a photoelectric conversion section. As in the first embodiment, the wavelength selective switch switches the optical path of the received light for each wavelength to separate the received light into optical signals for each wavelength, and the photoelectric conversion section photoelectrically converts the separated optical signals.

<Effect>
In the second embodiment, compared to the first embodiment, the emission direction of the measurement light can be varied by the grating constant of the grating waveguide 101A4, so that the beam can be irradiated to a desired location on the inspection object 3.

<Modified example>
FIG. 11 is a configuration diagram showing a modification of the optical integrated spectroscopic sensor 1A of the second embodiment. By changing the dimensions of the diffraction grating for each area of the grating waveguide, the emission direction can be changed for each area of the diffraction grating. Therefore, by configuring the grating waveguide 101A8 to have a waveguide structure in which the diffraction direction differs for each wavelength, it becomes possible to emit light rays in a plurality of directions from the light emitting section 101A. As in the example shown in FIG. 11, by forming the light blocking part 13 so that the light blocking part 13 has two windows 12 and providing two light receiving parts 102A, light rays from the light emitting part 101 are directed toward the two windows 12. It is possible to emit internal information at two locations on the inspection object 3 at once. For example, a waveguide structure may be formed in the grating waveguide 101A8 so that a light beam with a wavelength λ ₁ is emitted toward one window 12 and a light beam with a wavelength λ ₂ is emitted toward the other window 12. Three or more windows 12 may be provided to acquire internal information of three or more locations of the inspection object 3 at once. In this way, the optical integrated spectroscopic sensor 1A is modified so that the grating waveguide 101A8 has a waveguide structure with different diffraction directions for each wavelength, and the light shielding part 13 has a plurality of windows 12 according to the number of diffraction directions. You may.

<Additional notes>
Some aspects of the various embodiments described above are summarized as follows.

(Additional note 1)
The optical integrated spectroscopic sensor of Appendix 1 includes a light emitting unit (101; 101A) having at least one light source that emits a light beam, and a light receiving unit (101; 101A) having at least one light receiving element that receives scattered reflected light of the emitted light beam. 102; 102A); and at least one window (12) provided on the surface of the sensor chip and transmitting the emitted light beam and the scattered reflected light, and the area around the at least one window. A light shielding part (13) that shields light.

(Additional note 2)
The optically integrated spectroscopic sensor of Appendix 2 is the optically integrated spectroscopic sensor described in Appendix 1, in which the sensor chip further includes a protective layer (11) that protects the light emitting section and the light receiving section, and the light shielding layer portion is provided on the surface of the protective layer.

(Additional note 3)
The optical integrated spectroscopic sensor of Appendix 3 is the optical integrated spectroscopic sensor described in Appendix 2, in which the protective layer is a mold layer formed of a resin molding material.

(Additional note 4)
The optically integrated spectral sensor of Appendix 4 is the optically integrated spectral sensor described in any one of Supplementary Notes 1 to 3, in which the light-shielding portion is formed of light-shielding ink.

(Appendix 5)
The optical integrated spectroscopic sensor of Appendix 5 is the optical integrated spectroscopic sensor described in any one of Appendixes 1 to 4, in which the light receiving section (102) converts light of different wavelengths into optical signals for each wavelength. a wavelength selective switch (1023) that branches the optical signal into an electrical signal, and at least one photoelectric conversion unit (1024) that converts the optical signal guided by the wavelength selective switch into an electrical signal; The light emitting section (101) is configured to be able to emit light beams of a plurality of wavelengths.

(Appendix 6)
The optical integrated spectroscopic sensor of Appendix 6 is the optical integrated spectroscopic sensor described in Appendix 5, which converts the electrical signal converted by the photoelectric conversion unit into a wireless signal and transmits the converted wireless signal. The wireless signal converter (103) further includes a wireless signal converter (103).

(Appendix 7)
The optically integrated spectroscopic sensor of Appendix 7 is the optically integrated spectroscopic sensor described in Appendix 1, in which the light emitting section (101A) includes a plurality of light sources (101A1) that emit light beams with different wavelengths, and a plurality of light sources that emit light beams having different wavelengths. It includes a multiplexing waveguide (101A2) that multiplexes a plurality of light beams, and a grating waveguide (101A4) that outputs the multiplexed light beams.

(Appendix 8)
The optical integrated spectroscopic sensor according to appendix 8 is the optical integrated spectroscopic sensor described in appendix 7, in which the grating waveguide has a waveguide structure in which the diffraction direction differs for each wavelength, and the at least one window is A plurality of windows are provided according to the number of diffraction directions.

(Appendix 9)
The optical integrated spectroscopic sensor according to appendix 9 is the optical integrated spectroscopic sensor described in appendix 7 or 8, wherein the sensor chip further includes a protective layer (11) that protects the light emitting part and the light receiving part, The light shielding layer is provided on the surface of the protective layer.

(Appendix 10)
The optical integrated spectroscopic sensor of Appendix 10 is the optical integrated spectroscopic sensor described in Appendix 9, in which the protective layer is a mold layer formed of a resin molding material.

(Appendix 11)
The optical integrated spectroscopic sensor of Appendix 11 is the optical integrated spectroscopic sensor described in Appendix 7, in which the light-shielding layer is formed of a light-shielding ink.

(Appendix 12)
The optical integrated spectroscopic sensor of Appendix 12 is the optical integrated spectroscopic sensor described in any one of Appendixes 7 to 11, which converts the electrical signal converted by the photoelectric conversion unit into a wireless signal, It further includes a wireless signal converter (103) that transmits the converted wireless signal.

(Appendix 13)
The measurement system set forth in Appendix 13 includes the light-integrating spectral sensor described in any one of Supplementary notes 1 to 12, and an analysis unit that performs analysis based on the reflected light acquired by the light-integrating spectral sensor. An analysis device (4).

(Appendix 14)
The measurement method of appendix 14 includes the step (U1) of bringing the optically integrated spectroscopic sensor described in any one of appendices 1 to 12 into contact with the test object directly or through a thin film sheet; a step (U2) of operating a spectroscopic sensor to acquire a signal based on the scattered reflected light of the inspection target acquired by the optical integrated spectroscopic sensor from the optical integrated spectroscopic sensor using an analysis device; and a step (U3) of analyzing the signal using the analysis device.

Note that it is possible to combine the embodiments, or to modify or omit each embodiment as appropriate.

The optical integrated spectroscopic sensor of the present disclosure can be used as an optical sensor for optically measuring an inspection target such as food.

1 (1A) Optical integrated spectroscopic sensor, 1C (1CA) sensor chip, 2 thin film sheet, 3 inspection object, 4 analysis device, 6 food tray, 10 substrate, 11 protective layer, 12 window, 13 light shielding part, 31 food, 32 Blade, 101 (101A) Light emitting part, 101A1 Light source, 101A2 Combined waveguide, 101A3 Linear waveguide, 101A4 Grating waveguide, 101A6 Prism, 101A7 Coupling waveguide, 101A8 Grating waveguide, 102 (102 A) Light receiving section, 103 Wireless signal converter, 104 Power source, 401 Wireless signal converter, 402 Analysis unit, 403 Display device, 404 Power supply unit, 405 Wireless signal converter, 1013 Linear waveguide, 1015 Temperature adjustment unit, 1017 Coupling waveguide, 1021 Grating Waveguide, 1022 Linear waveguide, 1023 Wavelength selective switch, 1024 Photoelectric conversion unit, 1033 Linear waveguide.

Claims

A sensor chip comprising: a light emitting section having at least one light source that emits a light beam; and a light receiving section having at least one light receiving element that receives scattered reflected light of the emitted light beam;
a light shielding section provided on the surface of the sensor chip, having at least one window that transmits the emitted light beam and the scattered reflected light, and shielding light around the at least one window;
A light-integrated spectroscopic sensor equipped with
The sensor chip further includes a protective layer that protects the light emitting part and the light receiving part,
The light shielding portion is provided on the surface of the protective layer.
The optical integrated spectroscopic sensor according to claim 1.
The protective layer is a mold layer formed of a resin mold material,
The optical integrated spectroscopic sensor according to claim 2.
The light shielding portion is formed of light shielding ink.
The optical integrated spectroscopic sensor according to any one of claims 1 to 3.
The light receiving section is
a wavelength selective switch that branches light of different wavelengths into optical signals of each wavelength and guides the branched optical signals;
at least one photoelectric conversion unit that converts an optical signal guided by the wavelength selective switch into an electrical signal;
Equipped with
The light emitting section is configured to be able to emit light beams of a plurality of wavelengths,
The optical integrated spectroscopic sensor according to any one of claims 1 to 4.
a wireless signal converter that converts the electrical signal converted by the photoelectric conversion unit into a wireless signal and transmits the converted wireless signal;
further comprising;
The optical integrated spectroscopic sensor according to claim 5.
The light emitting part is
multiple light sources that emit light rays with different wavelengths;
a combining waveguide that combines the plurality of emitted light beams;
a grating waveguide that emits the combined light beam;
Equipped with
The optical integrated spectroscopic sensor according to claim 1.
The grating waveguide has a waveguide structure with different diffraction directions for each wavelength,
The at least one window is a plurality of windows provided according to the number of diffraction directions,
The optical integrated spectroscopic sensor according to claim 7.
The sensor chip further includes a protective layer that protects the light emitting part and the light receiving part,
The light shielding portion is provided on the surface of the protective layer.
The optical integrated spectroscopic sensor according to claim 7 or 8.
The protective layer is a mold layer formed of a resin mold material,
The optical integrated spectroscopic sensor according to claim 9.
The light shielding portion is formed of light shielding ink.
The optical integrated spectroscopic sensor according to claim 7.
a wireless signal converter that converts the electrical signal converted by the photoelectric conversion unit into a wireless signal and transmits the converted wireless signal;
further comprising;
The optical integrated spectroscopic sensor according to any one of claims 7 to 11.
The optical integrated spectroscopic sensor according to any one of claims 1 to 12,
an analysis device including an analysis unit that performs analysis based on the reflected light acquired by the optical integrated spectroscopic sensor;
Equipped with
measurement system.
A step of bringing the optical integrated spectroscopic sensor according to any one of claims 1 to 12 into contact with an object to be inspected directly or through a thin film sheet;
operating the optical integrated spectroscopic sensor to obtain a signal based on the scattered reflected light of the inspection object acquired by the optical integrated spectroscopic sensor from the optical integrated spectroscopic sensor using an analysis device;
analyzing the acquired signal using the analysis device;
Equipped with
Measuring method.