Near-infrared light-emitting device and biological information detection device provided with same

Abstract

This near-infrared light-emitting device (10) is provided with a solid-state light-emitting element (1) and a wavelength conversion body (2) containing a phosphor, and emits two or more fluorescent components from one light output surface. The two or more fluorescent components include a first fluorescent component and a second fluorescent component arranged side by side in order from the short wavelength side. For the spectral shape of the first fluorescent component, the slope of a long-wavelength region from the fluorescence peak of the first fluorescent component is steeper than the slope of a short-wavelength region, and for the spectral shape of the second fluorescent component, the slope of a short-wavelength region from the fluorescence peak of the second fluorescent component is steeper than the slope of the long-wavelength region. The second fluorescent component has the fluorescence peak in the wavelength range of 780 nm or more and 1000 nm or less.

Description

Technical Field

[0001] This invention relates to near-infrared emitting devices and biological information detection devices having the same. Background Technology

[0002] Previously, in fields such as biochemistry, medicine, agronomy, and nutrition, dual-wavelength methods (dual-wavelength spectrophotometry) were used to detect specified substances even when it was difficult to completely separate the sample. Additionally, dual-wavelength methods are also used to identify substances added to various foods, spoilage products, and substances added to various pharmaceuticals.

[0003] The dual-wavelength method involves measuring the absorbance at a first wavelength (the wavelength of maximum absorption) and a second wavelength (set to a longer wavelength range), and then quantifying the concentration of a target substance based on the difference in absorbance between the dominant and secondary wavelengths. For example, pulse oximeters use both red and infrared light to determine the proportion of oxygen-bound hemoglobin in the blood.

[0004] As a device for detecting biological information using such a dual-wavelength method, the device described in Patent Document 1 is known. Patent Document 1 discloses a biological information detection device for detecting blood-related biological information such as blood oxygen saturation or hemoglobin concentration in a non-contact manner. This biological information detection device includes: a light source that irradiates the biological subject with measuring light based on multiple different wavelengths; and an irradiation angle adjustment unit as an irradiation position adjustment unit that adjusts the irradiation position of the multiple different wavelengths of light according to the measurement distance to the biological subject. The biological information detection device also includes: an imaging unit as a light receiving unit that receives reflected light from the biological subject; and a processing unit that calculates biological information based on the intensity of the reflected light. According to this biological information detection device, the subject is irradiated with multiple different wavelengths of measuring light at the same irradiation position, and blood oxygen saturation or hemoglobin concentration is calculated based on the intensity of the reflected light at the irradiation position, thereby detecting biological information in a non-contact manner.

[0005] Existing technical documents Patent documents Patent Document 1: Japanese Patent No. 6832512 Summary of the Invention

[0006] In the dual-wavelength method, two or more light sources are typically used to illuminate two different wavelengths of light. However, when multiple light sources of different wavelengths are arranged, the light illuminating the object being measured becomes uneven due to the different optical axes of each source. Sometimes, the intensity balance varies depending on the irradiation location. Moreover, uneven illumination of the light illuminating the object can adversely affect the measurement results.

[0007] The present invention was made in view of the problems existing in the prior art. Moreover, the object of the present invention is to provide a near-infrared emitting device that can suppress uneven illumination of the light illuminating the object being measured even when irradiated with two different wavelengths of light, and a biological information detection device equipped with the near-infrared emitting device.

[0008] To address the aforementioned problems, the first aspect of the present invention relates to a near-infrared emitting device comprising a solid-state emitting element and a wavelength converter including a phosphor, and is a near-infrared emitting device emitting two or more fluorescent components from a single light output surface. The two or more fluorescent components include a first fluorescent component and a second fluorescent component arranged side-by-side sequentially from the short wavelength side, wherein the first and second fluorescent components are fluorescence based on electronic energy transitions of transition metal ions. The spectral shape of the first fluorescent component is such that the slope of the long-wavelength region from the fluorescence peak of the first fluorescent component is steeper than the slope of the short-wavelength region. The spectral shape of the second fluorescent component is such that the slope of the short-wavelength region from the fluorescence peak of the second fluorescent component is steeper than the slope of the long-wavelength region. The luminescence intensity at the long wavelength end of the first fluorescent component is 10% of the maximum luminescence intensity of the fluorescence peak of the first and second fluorescent components, and the luminescence intensity at the short wavelength end of the second fluorescent component is 10% of the maximum luminescence intensity. The second fluorescent component has the fluorescence peak in a wavelength range of 780 nm to 1000 nm.

[0009] The second aspect of the present invention relates to a near-infrared emitting device comprising a solid-state light-emitting element and a wavelength converter including a phosphor, and is a near-infrared emitting device emitting two or more fluorescent components from a single light output surface. The near-infrared emitting device further comprises a notch filter for controlling the wavelength-converted light obtained by the wavelength converter. The fluorescent components, separated by a blocking region controlled by the notch filter, have a first fluorescent component on the short wavelength side and a second fluorescent component on the long wavelength side. The first and second fluorescent components are fluorescence based on electronic energy transitions of transition metal ions. The second fluorescent component has a fluorescence peak in the wavelength range of 780 nm to 1000 nm.

[0010] The biological information detection device according to the third aspect of the present invention includes a near-infrared emitting device. Attached Figure Description

[0011] [ Figure 1 ] Figure 1 This is a graph showing the relationship between the irradiation position of the object being measured and the emission spectrum of the irradiated light when two light-emitting diodes with different wavelengths of irradiated light are used as the light source for the dual-wavelength method.

[0012] [ Figure 2 ] Figure 2 This is a graph showing the relationship between the irradiation position of the object being measured and the emission spectrum of the irradiated light when using a light-emitting device equipped with a near-infrared phosphor as the light source for the dual-wavelength method.

[0013] [ Figure 3 ] Figure 3 (a) is a schematic diagram showing an example of the configuration of the near-infrared emitting device of this embodiment. Figure 3 (b) is a diagram showing an example of the spectral distribution of the output light emitted from the near-infrared emitting device of this embodiment. Figure 3 (c) is a diagram showing an example of the spectral distribution of wavelength-converted light emitted from the wavelength converter and transmitted through a notch filter in the near-infrared light-emitting device of this embodiment.

[0014] [ Figure 4 ] Figure 4 This is a diagram showing an example of the spectral distribution of the output light emitted from the near-infrared emitting device of this embodiment.

[0015] [ Figure 5 ] Figure 5 This is a schematic diagram illustrating an example of the biological information detection device of this embodiment. Detailed Implementation

[0016] Hereinafter, the near-infrared emitting device of this embodiment and the biological information detection device equipped with the near-infrared emitting device will be described in detail with the help of the accompanying drawings. In addition, for ease of explanation, the scale of the drawings is exaggerated and sometimes differs from the actual scale.

[0017] [Near-infrared emitting device] In the dual-wavelength method, at least two light sources are generally used when illuminating two different wavelengths of light. For example, Figure 1 As shown, a light-emitting device is used, in which two light-emitting diodes (LEDs) with different output light wavelengths are arranged side-by-side relative to the object being measured. Furthermore, a camera is positioned between the two LEDs to detect reflected light from the object being measured. In this light-emitting device, one LED is a near-infrared LED with an output light emission peak wavelength of 780 nm. The other LED is also a near-infrared LED with an output light emission peak wavelength of 850 nm. Both LEDs emit sharp output light with narrow half-peak widths (HWHM).

[0018] Furthermore, in use Figure 1When the light-emitting device shown illuminates near-infrared light onto the face of a person being measured, both near-infrared light with a wavelength of 780 nm and near-infrared light with a wavelength of 850 nm are emitted. Here, in the light illuminating the left half of the person's face, the intensity of the 780 nm near-infrared light is greater than that of the 850 nm near-infrared light. Conversely, in the light illuminating the right half of the person's face, the intensity of the 850 nm near-infrared light is greater than that of the 780 nm near-infrared light. Thus, with multiple light sources of different wavelengths arranged, the near-infrared light illuminating the person's face is uneven due to the different optical axes of each light source, resulting in an intensity balance that varies depending on the illuminating environment. Furthermore, the temperature characteristics of the two types of light-emitting diodes are also different, therefore, the intensity balance also changes depending on the ambient temperature.

[0019] To suppress such uneven irradiation of the test subject, instead of Figure 1 LED method, Figure 2 The fluorescent method has attracted attention. Figure 2 The light-emitting device comprises a solid-state light-emitting element and a wavelength converter containing a near-infrared phosphor. It emits near-infrared light from a light output surface after wavelength conversion of primary light emitted from the solid-state light-emitting element using the near-infrared phosphor. Furthermore, a camera is positioned near the light-emitting device to detect reflected light from the target object. The near-infrared light emitted from this device is a broad fluorescence with a large half-width at half-maximum (HWHM). Moreover, by using two fluorescent components of the broad fluorescence, the target substance can be quantified. For example, in… Figure 2 In the light-emitting device, fluorescent components with wavelengths around 780 nm and around 850 nm are used to quantify the target substance.

[0020] Here, in use Figure 2 When the light-emitting device shown illuminates near-infrared light onto the face of a person being measured, both the left and right halves of the person's face are illuminated with near-infrared light of constant and balanced intensity. That is, in Figure 2 In the light-emitting device, since near-infrared light is emitted from a single light output surface, there is only one optical axis. Furthermore, even if there are multiple solid-state light-emitting elements and wavelength converters, the optical axis remains the same because the light output surface emitting near-infrared light is singular. Therefore, since the intensity balance of near-infrared light is constant at any location on the target object, high-precision quantification of the target substance can be achieved by detecting the dual-wavelength reflected light from the target object. Additionally, Figure 2 The light-emitting device uses a wavelength converter containing a near-infrared phosphor. The wavelength converter has constant temperature characteristics, so the intensity balance of the irradiated light is difficult to change even if the ambient temperature changes.

[0021] Thus, with Figure 1 The light-emitting devices are different from those using LEDs. Figure 2 The phosphor-based luminescent device has the following characteristics: the optical axis of the near-infrared light irradiating the object being measured is the same, and the intensity balance is constant at any location on the object being measured.

[0022] Here, in Figure 1 LED-based light-emitting devices and Figure 2 In phosphor-based light-emitting devices, light with wavelengths around 780 nm and around 850 nm is emitted, for example. Additionally, in... Figure 2 The light-emitting device also emits fluorescence with wavelengths between 780 nm and 850 nm, specifically fluorescence in the wavelength range of 790 nm to 840 nm. Furthermore, from... Figure 2 The near-infrared light emitted by the light-emitting device has a fluorescence peak in the wavelength range of 790-840nm, therefore the fluorescence intensity is high in the wavelength range of 790nm-840nm.

[0023] When near-infrared light, which is not used in such dual-wavelength quantification but has high intensity, is irradiated onto the person being measured, it may cause discomfort such as eye irritation and / or thermal discomfort. Therefore, when irradiating the person being measured with near-infrared fluorescence, it is preferable to remove light of unwanted wavelengths other than the dual wavelengths used in the quantitative determination.

[0024] The light-emitting device of this embodiment is capable of suppressing uneven illumination of the light illuminating the object to be measured and suppressing unwanted fluorescence even when irradiated with two different wavelengths of light.

[0025] like Figure 3 As shown in (a), the near-infrared emitting device 10 of this embodiment includes: a solid-state emitting element 1 that emits primary light; and a wavelength converter 2 that includes a phosphor that has the property of absorbing primary light and converting it into a light component with a wavelength longer than the primary light. The near-infrared emitting device 10 also includes an optical component 3 that has the property of attenuating a portion of the fluorescence emitted by the phosphor included in the wavelength converter 2 but allowing the remaining fluorescence to be transmitted.

[0026] A solid-state light-emitting element 1 is mounted on the surface (main surface) 4a of the substrate 4. The solid-state light-emitting element 1 can be, for example, a light-emitting diode (LED) or a laser diode. Furthermore, by using an LED module or laser diode that emits high-energy light of 1W or more, a near-infrared light-emitting device capable of expecting light output in the hundreds of mW range can be achieved. Additionally, by using an LED module that emits high-energy light of 3W or more or 10W or more, a near-infrared light-emitting device capable of expecting light output in the several W range can be achieved. Furthermore, by using an LED module that emits high-energy light of 30W or more, a near-infrared light-emitting device capable of expecting light output exceeding 10W can be achieved. Moreover, by using an LED module that emits high-energy light of 100W or more, a near-infrared light-emitting device capable of expecting light output exceeding 30W can be achieved.

[0027] If a laser diode is used as the solid-state light-emitting element 1 to convert primary light into laser light, it becomes a form that irradiates the wavelength converter 2 with high-density point light. Therefore, the resulting near-infrared light-emitting device can serve as a high-output point light source, thus expanding the industrial applications of solid-state lighting. Examples of such laser diodes include edge-emitting lasers (EELs) and vertical-cavity surface-emitting lasers (VCSELs).

[0028] The primary light emitted by the solid-state light-emitting element 1 is preferably blue light with a maximum intensity in the wavelength region of 435 nm or higher and less than 480 nm. Solid-state light-emitting elements that emit high-output and high-efficiency blue light are readily available, thus facilitating the realization of high-output and high-efficiency near-infrared light-emitting devices, which in turn benefits the industrial production of near-infrared light-emitting devices.

[0029] Furthermore, the number of solid-state light-emitting elements 1 mounted on the substrate 4 is not particularly limited; it can be a single element or multiple elements. Having multiple solid-state light-emitting elements 1 makes it easier to increase the output of primary light, thus making it a near-infrared light-emitting device that facilitates high output. The number of solid-state light-emitting elements 1 is not particularly limited; for example, it can be appropriately selected from 9 or more, 16 or more, 25 or more, 36 or more, 49 or more, 64 or more, 81 or more, or 100 or more. Additionally, there is no particular upper limit to the number; for example, it can be appropriately selected from 9 or less, 16 or less, 25 or less, 36 or less, 49 or less, 64 or less, 81 or less, or 100 or less.

[0030] In the near-infrared light-emitting device 10, the solid-state light-emitting element 1 is preferably a surface-emitting light source of the surface-emitting type. As a result, deviations in the intensity distribution and unevenness in the color tone of the primary light irradiating the wavelength converter 2 can be suppressed, thus making it a near-infrared light-emitting device that is advantageous for suppressing uneven intensity distribution of the output light.

[0031] The material of substrate 4 is not particularly limited. For example, a substrate made of metal can be used, specifically, a substrate made of aluminum can be used. Alternatively, substrate 4 can be made of ceramic, specifically, a substrate made of alumina.

[0032] Wavelength converter 2 is stacked on the upper surface of solid-state light-emitting element 1. Furthermore, wavelength converter 2 preferably contains a near-infrared phosphor. A near-infrared phosphor is a phosphor that absorbs primary light emitted by solid-state light-emitting element 1 and converts it into wavelength-converted light containing near-infrared light. Preferably, such a near-infrared phosphor emits near-infrared light with a fluorescence peak in a wavelength range of 730 nm or more and less than 2500 nm; more preferably, it emits near-infrared light with a fluorescence peak in a wavelength range of 780 nm or more and less than 2500 nm. Additionally, a near-infrared phosphor that emits near-infrared light with a fluorescence peak in a wavelength range of 730 nm or more and less than 1000 nm is preferred; more preferably, it emits near-infrared light with a maximum intensity in a wavelength range of 780 nm or more and less than 1000 nm. This allows for easy conversion of the primary light wavelength emitted by the solid-state light-emitting element into near-infrared light components, and is therefore suitable, for example, in obtaining the near-infrared light components required for measurement.

[0033] As a near-infrared phosphor, various inorganic phosphors known as near-infrared light sources can be used, for example. Specifically, as a near-infrared phosphor, a phosphor that is activated by at least one of transition metal ions and rare earth ions and emits fluorescence containing a near-infrared light component can be used. The transition metal ion is preferably selected from Ti. 3+ V 4+ Cr 4+ V 3+ Cr 3+ V 2+ Mn 4+ Fe 3+ Co 3+ Co 2+ and Ni 2+ At least one of the group consisting of rare earth ions. Rare earth ions are preferably selected from Nd. 3+ Eu 2+ Ho 3+ Er 3+ Tm 3+ and Yb 3+At least one of the groups. Moreover, the near-infrared phosphor is preferably an oxide, sulfide, nitride, halide, oxysulfide, oxynitride, or oxyhalide containing the fluorescent ion.

[0034] The near-infrared phosphor included in wavelength converter 2 can be at least one selected from the group consisting of halophosphates, phosphates, halosilicates, silicates, aluminates, aluminosilicates, borates, germanates, silicates nitrides, aluminum silicates nitrides, oxonides, and aluminum silicates nitrides activated by the aforementioned activator. Therefore, the phosphor can be selected appropriately from these sources to suit the lighting design.

[0035] Here, the activator of the near-infrared phosphor contained in the wavelength converter 2, i.e., the fluorescent ion, is preferably Cr. 3+ Through Cr 3+ By utilizing [the technology], phosphors with the property of absorbing visible light, especially blue or red light, and converting it into a deep red to near-infrared light component can be obtained. Furthermore, depending on the type of parent compound containing the activator, the wavelength of the phosphor's absorption peak or fluorescence peak can be easily altered, which is advantageous in changing the shape of the excitation and fluorescence spectra. Moreover, many phosphors that absorb blue or red light and convert it into a near-infrared fluorescent component are known to be derived from Cr [the phosphor / phosphor]. 3+ Activated phosphor. Therefore, not only is the range of solid-state light-emitting elements 1 that emit primary light wider, but the peak wavelength of the fluorescence emitted by the phosphor can also be easily changed, thus making it a near-infrared light-emitting device 10 that is advantageous for controlling the spectral distribution of the output light.

[0036] In addition, the fluorescent ion is Cr 3+ Any phosphor can absorb excitation light (primary light) and convert it into fluorescence with a wavelength longer than that excitation light; there are no particular limitations. From known Cr... 3+ Appropriate selection of activators is sufficient. However, Cr 3+ The activated phosphor is preferably a phosphor based on an easily manufactured composite metal oxide.

[0037] Cr 3+ The activating phosphor is preferably a composite oxide phosphor with a garnet-type crystal structure, which has achieved various practical applications. 3+ Activating garnet fluorophores can be achieved by selecting Y3Al2(AlO4)3:Cr 3+ La3Al2(AlO4)3:Cr 3+ Gd3Al2(AlO4)3:Cr 3+ Y3Ga2(AlO4)3:Cr 3+ La3Ga2(AlO4)3:Cr 3+ Gd3Ga2(AlO4)3:Cr 3+ Y3Sc2(AlO4)3:Cr 3+ La3Sc2(AlO4)3:Cr 3+ Gd3Sc2(AlO4)3:Cr 3+ Y3Ga2(GaO4)3:Cr 3+ La3Ga2(GaO4)3:Cr 3+ (Gd,La)3Ga2(GaO4)3:Cr 3+ Gd3Ga2(GaO4)3:Cr 3+ Y3Sc2(GaO4)3:Cr 3+ La3Sc2(GaO4)3:Cr 3+ Gd3Sc2(GaO4)3:Cr 3+ and (Gd,La)3(Ga,Sc)2(GaO4)3:Cr 3+ At least one of the groups. Additionally, Cr 3+ Activated garnet fluorophores can also be solid solutions with these fluorophores as end components.

[0038] In addition, the near-infrared phosphor contained in wavelength converter 2 can also be selected from Y4CdMo3O 16 Yb 3+ K3LuSi2O7:Eu 2+ CaO: Eu 2+ 、Sr 2-y Ca y InSbO6:Fe 3+ La3Ga5GeO 14 Cr 3+ ScBO3:Cr 3+ and Ga 2-x Sc x O3:Cr 3+ At least one of the groups.

[0039] Here, the spectral distribution of near-infrared light emitted from the near-infrared phosphor, when displayed as a histogram showing the intensity per 10 nm wavelength, is preferably unimodal. In this specification, "unimodal" refers to a distribution where the histogram has only one peak. By making this spectral distribution unimodal, the near-infrared light component is concentrated within a specific wavelength range, thus creating a near-infrared light-emitting device that facilitates high output and high efficiency of near-infrared light.

[0040] The wavelength converter 2 can be fabricated by sealing the phosphor with a sealing material. The sealing material is preferably at least one of an organic material and an inorganic material, and particularly preferably at least one of a transparent (transparent) organic material and a transparent (transparent) inorganic material. Examples of organic sealing materials include transparent organic materials such as silicone resin. Examples of inorganic sealing materials include transparent inorganic materials such as low-melting-point glass.

[0041] Furthermore, as the wavelength converter 2, a sintered body with multiple pores formed by sintering a phosphor can be used. Alternatively, a ceramic body without multiple pores can also be used as the wavelength converter 2. By making the wavelength converter 2 a sintered body or a ceramic body in this way, its manufacturing and processing become easier, thus making it suitable for industrial production. In addition, by using such a sintered body or ceramic body, fluorescent ions are distributed at a high density in the thickness direction, which makes it easier to achieve a higher light absorption rate of the wavelength converter, further improving the fluorescence output ratio.

[0042] The near-infrared emitting device 10 includes an optical component 3, which is disposed on the surface (upper surface) of the wavelength converter 2 opposite to the solid-state emitting element 1. Additionally, as... Figure 3 As shown in (a), the optical component 3 covers the entire upper surface of the wavelength converter 2. Moreover, the optical component 3 has the property of attenuating a portion of the fluorescence emitted by the near-infrared phosphor contained in the wavelength converter 2, but allowing the remaining fluorescence to pass through.

[0043] In the near-infrared emitting device 10, the optical component 3 is preferably a component made of only inorganic materials. The optical component 3 made of only inorganic materials has excellent heat resistance and durability, thus enabling a near-infrared emitting device with improved heat resistance and durability.

[0044] Furthermore, the optical component 3 preferably has a dielectric multilayer film structure. Thus, by utilizing the optical interference effect observed in the multilayer structure of dielectrics with different dielectric constants, it is possible to obtain optical properties that attenuate a portion of the fluorescence emitted by the near-infrared phosphor, but allow the remaining fluorescence to pass through.

[0045] Optical component 3 is preferably an optical interference filter. An optical interference filter is a component formed by forming a dielectric thin film on the surface of a substrate. Furthermore, the dielectric thin film alters the light transmission characteristics by utilizing interference generated through reflections at interfaces between air and the dielectric, between the dielectric and the substrate, and between different dielectrics. By using such an optical interference filter, the transmittance of a portion of the fluorescence emitted by the near-infrared phosphor can be reduced, while the transmittance of other fluorescence can be relatively increased. Moreover, the design and acquisition of optical interference filters are relatively easy, thus allowing for the relatively easy construction of the desired light-emitting device.

[0046] Optical component 3 is more preferably a notch filter. Notch filters are also known as bandstop filters. Notch filters have the characteristic of attenuating light in a specific wavelength band (stopband, blocking region) to a very low level, while allowing light of most other wavelengths to be transmitted with minimal intensity loss. By using a notch filter as optical component 3, unwanted wavelengths of light other than the two wavelengths can be removed when near-infrared fluorescence is irradiated onto the object being measured.

[0047] The operation of the near-infrared emitting device 10 of this embodiment, having such a configuration, will be explained. For example... Figure 3 As shown in (a), in the near-infrared light-emitting device 10, firstly, when power is applied to the solid-state light-emitting element 1 of the near-infrared light-emitting device 10, primary light is emitted upward from the solid-state light-emitting element 1. The emitted primary light is transmitted through the wavelength converter 2, at which time a portion of the primary light is absorbed by the fluorescent ions of the near-infrared phosphor contained in the wavelength converter 2. Furthermore, the fluorescent ions are converted into near-infrared light as wavelength-converted light through electron energy transitions, and emitted from the phosphor.

[0048] Near-infrared fluorescence emitted by a near-infrared phosphor, such as Figure 3 As shown in (c), it becomes a broad spectroscopic distribution with a large half-width, and is therefore preferably a single-peak type.

[0049] Then, the near-infrared light emitted from the wavelength converter 2 reaches the optical component 3. As described above, the optical component 3 has the property of attenuating a portion of the near-infrared light and allowing the remaining fluorescence to pass through. Therefore, near-infrared fluorescence incident from one surface 3a of the optical component 3 is attenuated by the optical component 3, while the remaining fluorescence is transmitted. Then, the fluorescence is output from the other surface 3b of the optical component 3. Figure 3 (b) shows the near-infrared light with a spectral distribution. In this way, the near-infrared emitting device 10 can output a portion of the attenuated near-infrared fluorescence emitted from the wavelength converter 2.

[0050] Here, the output light emitted from the near-infrared emitting device 10 of this embodiment will be described in detail.

[0051] The near-infrared emitting device 10 emits light from the other side 3b of the optical component 3, thus emitting a fluorescent component from a single light output surface. As a result, in the near-infrared emitting device 10, the fluorescent component has only one optical axis.

[0052] Furthermore, as described above, a portion of the near-infrared light emitted from the wavelength converter 2 is blocked by the optical component 3, therefore, as Figure 4 As shown, the output light has at least two fluorescent components. The two fluorescent components are a first fluorescent component and a second fluorescent component arranged side-by-side from the short wavelength side. In addition, the near-infrared phosphor contains a transition metal as an activator, so the first and second fluorescent components are fluorescence based on the electronic energy transitions of transition metal ions.

[0053] exist Figure 4 In the spectroscopic distribution shown, the fluorescence peak wavelength of the first fluorescent component is 804 nm, and the fluorescence peak wavelength of the second fluorescent component is 857 nm.

[0054] Furthermore, in the spectral shape of the first fluorescent component, the slope of the long-wavelength region starting from the fluorescence peak of the first fluorescent component is steeper than the slope of the short-wavelength region. Specifically, firstly, the short-wavelength end of the first fluorescent component is set to the wavelength of 10% of the maximum luminescence intensity of the fluorescence peak of the first and second fluorescent components, and the long-wavelength end of the first fluorescent component is set to the wavelength of 10% of that maximum luminescence intensity. More specifically, the short-wavelength end of the first fluorescent component is set to the wavelength of 10% of the intensity of the fluorescence peak of the first fluorescent component, i.e., wavelength 713 nm, and the long-wavelength end of the first fluorescent component is set to the wavelength of 10% of the intensity of the fluorescence peak of the first fluorescent component, i.e., wavelength 813 nm. Moreover, as... Figure 4 As shown, on the short wavelength side, which is shorter than the fluorescence peak of the first fluorescent component, the luminescence intensity continuously increases from 713 nm to 804 nm, but the slope is gentle. In contrast, on the long wavelength side, which is longer than the fluorescence peak of the first fluorescent component, the luminescence intensity continuously decreases from 804 nm to 813 nm, but the slope is steep.

[0055] In contrast, in the spectral shape of the second fluorescent component, the slope of the short-wavelength region starting from the fluorescence peak of the second fluorescent component is steeper than the slope of the long-wavelength region. Specifically, firstly, the short-wavelength end of the second fluorescent component is set to the wavelength of 10% of the maximum luminescence intensity of the fluorescence peaks of the first and second fluorescent components, and the long-wavelength end of the second fluorescent component is set to the wavelength of 10% of that maximum luminescence intensity. More specifically, the short-wavelength end of the second fluorescent component is set to the wavelength of 10% of the intensity of the fluorescence peak of the first fluorescent component, i.e., 847 nm, and the long-wavelength end of the second fluorescent component is set to the wavelength of 10% of the intensity of the fluorescence peak of the first fluorescent component, i.e., 1011 nm. Moreover, as... Figure 4 As shown, on the short wavelength side, which is shorter than the fluorescence peak of the second fluorescent component, the luminescence intensity continuously increases from 847 nm to 857 nm, but the slope is steep. In contrast, on the long wavelength side, which is longer than the fluorescence peak of the second fluorescent component, the luminescence intensity continuously decreases from 857 nm to 1011 nm, but the slope is gentle.

[0056] Furthermore, the luminescence intensity between the long-wavelength end of the first fluorescent component and the short-wavelength end of the second fluorescent component is less than 10% of the maximum luminescence intensity of the fluorescence peak of the first fluorescent component and the fluorescence peak of the second fluorescent component.

[0057] Thus, in the near-infrared luminescent device 10 of this embodiment, the first fluorescent component and the second fluorescent component are clearly separated. Furthermore, the luminescence intensity between the first and second fluorescent components is less than 10% of the maximum luminescence intensity of the fluorescence peaks of the first and second fluorescent components. Therefore, for example, by using a dual-wavelength method employing a fluorescent component with a wavelength around 770 nm and a fluorescent component with a wavelength around 880 nm, quantification of the target substance is possible. Moreover, the fluorescent component between the first and second fluorescent components, which is not used in dual-wavelength-based quantification, is significantly suppressed, thereby suppressing adverse effects such as discomfort to the analyte.

[0058] The first fluorescent component emitted by the near-infrared luminescent device 10 will be described in more detail. In the spectral shape of the first fluorescent component, when the maximum luminescence intensity of the fluorescence peaks of the first and second fluorescent components is set to 100%, the maximum value of the slope of the long-wavelength region from the fluorescence peak of the first fluorescent component is preferably 8% / nm or more. That is, when the maximum luminescence intensity is set to 100%, the maximum value of the slope of the long-wavelength region from the fluorescence peak of the first fluorescent component is preferably 8% or more per 1nm wavelength. In contrast, when the maximum luminescence intensity is set to 100%, the maximum value of the slope of the short-wavelength region from the fluorescence peak of the first fluorescent component is preferably less than 8% / nm. That is, when the maximum luminescence intensity is set to 100%, the maximum value of the slope of the short-wavelength region from the fluorescence peak of the first fluorescent component is preferably less than 8% per 1nm wavelength. With such a spectroscopic distribution, while cutting off the fluorescent component between the first and second fluorescent components, the intensity of the measurement light on the short-wavelength side in the dual-wavelength method is increased, thus improving the measurement accuracy of the target substance while suppressing adverse effects on the analyte.

[0059] Furthermore, in the spectroscopic distribution of the first fluorescent component, when the maximum luminescence intensity of the fluorescence peaks of the first and second fluorescent components is set to 100%, the maximum value of the slope of the long-wavelength region starting from the fluorescence peak of the first fluorescent component is preferably 10% / nm or more. Additionally, when this maximum luminescence intensity is set to 100%, the maximum value of the slope of the short-wavelength region starting from the fluorescence peak of the first fluorescent component is preferably less than 5% / nm.

[0060] The second fluorescent component emitted by the near-infrared luminescent device 10 will be described in more detail. In the spectral shape of the second fluorescent component, when the maximum luminescence intensity of the fluorescence peaks of the first and second fluorescent components is set to 100%, the maximum value of the slope of the short-wavelength region starting from the fluorescence peak of the second fluorescent component is preferably 8% / nm or more. That is, when this maximum luminescence intensity is set to 100%, the maximum value of the slope of the short-wavelength region starting from the fluorescence peak of the second fluorescent component is preferably 8% or more per 1nm wavelength. In contrast, when this maximum luminescence intensity is set to 100%, the maximum value of the slope of the long-wavelength region starting from the fluorescence peak of the second fluorescent component is preferably less than 8% / nm. That is, when this maximum luminescence intensity is set to 100%, the maximum value of the slope of the long-wavelength region starting from the fluorescence peak of the second fluorescent component is preferably less than 8% per 1nm wavelength. With such a spectroscopic distribution, while cutting off the fluorescent component between the first and second fluorescent components, the intensity of the measurement light on the long-wavelength side in the dual-wavelength method is increased, thus improving the measurement accuracy of the target substance while suppressing adverse effects on the analyte.

[0061] Furthermore, in the spectroscopic distribution of the second fluorescent component, when the maximum luminescence intensity of the fluorescence peaks of the first and second fluorescent components is set to 100%, the maximum value of the slope of the short-wavelength region starting from the fluorescence peak of the second fluorescent component is preferably 10% / nm or more. Additionally, when this maximum luminescence intensity is set to 100%, the maximum value of the slope of the long-wavelength region starting from the fluorescence peak of the second fluorescent component is preferably less than 5% / nm.

[0062] Furthermore, the short-wavelength end of the first fluorescent component is set to the wavelength that is 10% of the maximum luminescence intensity of the fluorescence peak of the first fluorescent component and the fluorescence peak of the second fluorescent component, and the long-wavelength end of the first fluorescent component is set to the wavelength that is 10% of the maximum luminescence intensity. Moreover, on the short-wavelength side of the first fluorescent component, the wavelength range from the short-wavelength end of the first fluorescent component to the fluorescence peak of the first fluorescent component is preferably 40 nm or more. Furthermore, on the long-wavelength side of the first fluorescent component, the wavelength range from the fluorescence peak of the first fluorescent component to the long-wavelength end of the first fluorescent component is preferably 15 nm or less. With this spectroscopic distribution, the fluorescence component between the first and second fluorescent components can be cut off, and the intensity of the measurement light on the short-wavelength side in the dual-wavelength method can be increased. Therefore, adverse effects on the analyte can be suppressed, and the measurement accuracy of the target substance can be improved.

[0063] Furthermore, the short-wavelength end of the second fluorescent component is set to the wavelength that is 10% of the maximum luminescence intensity of the fluorescence peak of the first and second fluorescent components, and the long-wavelength end of the second fluorescent component is set to the wavelength that is 10% of the maximum luminescence intensity. Moreover, on the short-wavelength side of the second fluorescent component, the wavelength range from the short-wavelength end to the fluorescence peak is preferably 15 nm or less. Furthermore, on the long-wavelength side of the second fluorescent component, the wavelength range from the fluorescence peak to the long-wavelength end is preferably 40 nm or more. This spectroscopic distribution also cuts off the fluorescence component between the first and second fluorescent components and increases the intensity of the measurement light on the long-wavelength side in the dual-wavelength method, thus suppressing adverse effects on the analyte and improving the measurement accuracy of the target substance.

[0064] In the near-infrared emitting device 10, the second fluorescent component preferably has a fluorescence peak in a wavelength range of 780 nm or higher and 1000 nm or lower. By ensuring that the fluorescence peak of the second fluorescent component is within this wavelength range, the measurement light on the longer wavelength side can be near-infrared light.

[0065] In the near-infrared emitting device 10, the first fluorescent component is located on the shorter wavelength side compared to the second fluorescent component, and therefore includes at least one of red light and near-infrared light. Therefore, the first fluorescent component preferably has a fluorescence peak in a wavelength range of 600 nm to 900 nm. By ensuring that the fluorescence peak of the first fluorescent component is within this wavelength range, the measurement light on the shorter wavelength side can be made to be at least one of red light and near-infrared light.

[0066] In the near-infrared luminescent device 10, the first and second fluorescent components are fluorescence based on the electronic energy transition of the same transition metal ion, preferably fluorescence based on dd or fd transitions. As described above, the near-infrared fluorescence emitted from the near-infrared phosphor of the wavelength converter 2 has a broad spectroscopic distribution with a large half-width, and is more preferably a single-peak type. Therefore, the near-infrared phosphor contains a transition metal ion as an activator, and the fluorescence emitted from the near-infrared phosphor is fluorescence based on the electronic energy transition of this transition metal ion, preferably fluorescence based on dd or fd transitions. Furthermore, when the fluorescence emitted from the transition metal ion is based on an ff transition, the fluorescence has a narrow half-width, resulting in a sharp spectroscopic distribution. Therefore, the fluorescence emitted from the transition metal ion is preferably not based on an ff transition.

[0067] In the near-infrared emitting device 10, the wavelength difference between the long-wavelength end of the first fluorescent component and the short-wavelength end of the second fluorescent component is preferably 20 nm or more and 100 nm or less. The long-wavelength end of the first fluorescent component is set to the wavelength of 10% of the maximum luminescence intensity of the fluorescence peaks of the first and second fluorescent components. The short-wavelength end of the second fluorescent component is set to the wavelength of 10% of this maximum luminescence intensity. Furthermore, it is preferable that the wavelength difference between the long-wavelength end of the first fluorescent component and the short-wavelength end of the second fluorescent component is within the above-mentioned range. As a result, the first and second fluorescent components are clearly separated, thus enabling the application of a dual-wavelength method.

[0068] In the near-infrared emitting device 10, two or more fluorescent components preferably originate from the emission of the same phosphor. That is, the first fluorescent component and the second fluorescent component preferably originate from the emission of the same phosphor. Therefore, it is easy to obtain... Figure 4 The fluorescence with the spectral distribution shown is therefore applicable to the dual-wavelength method.

[0069] In the near-infrared emitting device 10, the first fluorescent component preferably includes light components in the wavelength range of 600 nm or more and less than 900 nm. By including fluorescent components in this range in the first fluorescent component, it is possible to make the measurement light on the short wavelength side at least one of red light and near-infrared light.

[0070] In the near-infrared emitting device 10, the first and second fluorescent components are preferably fluorescence based on the electronic energy transition of transition metal ions, which are selected from Cr. 3+ Cr 4+ Fe 3+ and Eu 2+ At least one of the groups. In this case, the near-infrared fluorescence emitted from the near-infrared phosphor of wavelength converter 2 becomes a broad spectroscopic distribution with a large half-width, and thus easily becomes a single-peak type. Therefore, it is easy to obtain Figure 4 The fluorescence with the spectral distribution shown is therefore suitable for use in dual-wavelength methods.

[0071] Furthermore, in the above description, the luminescence intensity at the long wavelength end of the first fluorescent component is set to 10% of the maximum luminescence intensity of the fluorescence peaks of the first and second fluorescent components, and the luminescence intensity at the short wavelength end of the first fluorescent component is also set to 10% of this maximum luminescence intensity. Similarly, the luminescence intensity at the long wavelength end of the second fluorescent component is 10% of this maximum luminescence intensity, and the luminescence intensity at the short wavelength end of the second fluorescent component is also 10% of this maximum luminescence intensity. However, it is also possible to set the luminescence intensity at the long wavelength end of the first fluorescent component to 5% of the maximum luminescence intensity of the fluorescence peaks of the first and second fluorescent components, and the luminescence intensity at the short wavelength end of the first fluorescent component is also set to 5% of this maximum luminescence intensity. Similarly, it is also possible to set the luminescence intensity at the long wavelength end of the second fluorescent component to 5% of this maximum luminescence intensity, and the luminescence intensity at the short wavelength end of the second fluorescent component is also set to 5% of this maximum luminescence intensity. Alternatively, the luminescence intensity at the long wavelength end of the first fluorescent component can be set to 3% of the maximum luminescence intensity between the fluorescence peaks of the first and second fluorescent components, and the luminescence intensity at the short wavelength end of the first fluorescent component can also be set to 3% of this maximum luminescence intensity. Similarly, the luminescence intensity at the long wavelength end of the second fluorescent component can also be set to 3% of this maximum luminescence intensity, and the luminescence intensity at the short wavelength end of the second fluorescent component can also be set to 3% of this maximum luminescence intensity.

[0072] Furthermore, the overall luminescence intensity between the long-wavelength end of the first fluorescent component and the short-wavelength end of the second fluorescent component is generally less than 10% of the maximum luminescence intensity of the fluorescence peak of the first fluorescent component and the fluorescence peak of the second fluorescent component. However, the overall luminescence intensity between the long-wavelength end of the first fluorescent component and the short-wavelength end of the second fluorescent component can be less than 5% of this maximum luminescence intensity, or it can be less than 3%.

[0073] In the fluorescent components emitted by the near-infrared luminescent device 10, the luminescence intensity of the fluorescence peak of the first fluorescent component can be greater than that of the fluorescence peak of the second fluorescent component. Conversely, the luminescence intensity of the fluorescence peak of the first fluorescent component can also be less than that of the fluorescence peak of the second fluorescent component. Furthermore, the difference between the luminescence intensities of the first and second fluorescent components is preferably 50% or less, more preferably 30% or less, and even more preferably 10% or less. By minimizing the difference in luminescence intensities between the first and second fluorescent components, the intensity difference between the two measuring lights used in the two-component method is easily reduced, thereby improving the accuracy of the target substance measurement.

[0074] When performing quantitative analysis of a target substance using the near-infrared luminescence device 10 via a dual-wavelength method, the wavelengths of the measuring light used can be set, for example, to around 770 nm and 880 nm. However, this is not a limitation; the wavelengths of the measuring light can be set to around 610 nm and 880 nm. Furthermore, the wavelengths of the measuring light can be around 675 nm and 840 nm. Additionally, the wavelengths of the measuring light can be around 630 nm and 850 nm. The wavelengths of the measuring light can be around 660 nm and 850 nm. Furthermore, the wavelengths of the measuring light can be around 780 nm and 905 nm.

[0075] Thus, the near-infrared emitting device 10 of this embodiment has a solid-state emitting element 1 and a wavelength converter 2 containing a phosphor, and is a near-infrared emitting device that emits two or more fluorescent components from a single light output surface. Furthermore, the two or more fluorescent components include a first fluorescent component and a second fluorescent component arranged side-by-side sequentially from the short wavelength side. The first and second fluorescent components are fluorescence based on the electronic energy transition of transition metal ions. Regarding the spectral shape of the first fluorescent component, the slope of the long-wavelength region from the fluorescence peak of the first fluorescent component is steeper than the slope of the short-wavelength region; regarding the spectral shape of the second fluorescent component, the slope of the short-wavelength region from the fluorescence peak of the second fluorescent component is steeper than the slope of the long-wavelength region. Additionally, the luminescence intensity at the long-wavelength end of the first fluorescent component is 10% of the maximum luminescence intensity of the fluorescence peak of the first and second fluorescent components, and the luminescence intensity at the short-wavelength end of the second fluorescent component is 10% of this maximum luminescence intensity. Moreover, the second fluorescent component has a fluorescence peak in the wavelength range of 780 nm to 1000 nm.

[0076] Furthermore, the near-infrared light-emitting device 10 of this embodiment includes a solid-state light-emitting element 1 and a wavelength converter 2 containing a phosphor, and is a near-infrared light-emitting device that emits two or more fluorescent components from a single light output surface. The near-infrared light-emitting device 10 also includes a notch filter for controlling the wavelength-converted light after conversion by the wavelength converter. Moreover, the fluorescent components, separated by a blocking region controlled by the notch filter, have a first fluorescent component on the short wavelength side and a second fluorescent component on the long wavelength side. The first and second fluorescent components are fluorescence based on the electronic energy transition of transition metal ions. Furthermore, the second fluorescent component has the aforementioned fluorescence peak in a wavelength range of 780 nm to 1000 nm.

[0077] The near-infrared emitting device 10 emits a fluorescent component from a single light output surface; therefore, the optical axis of the fluorescent component is singular, resulting in a constant intensity balance at any location on the object being measured. Furthermore, the output light emitted from the near-infrared emitting device 10 has two fluorescent components, and the spectral distribution of these fluorescent components exhibits… Figure 4 The characteristic shape shown is thus achieved. Therefore, by using a dual-wavelength method, the target substance can be quantified with high precision, thereby significantly blocking the fluorescence component between the first and second fluorescent components, thus suppressing adverse effects such as discomfort to the analyte.

[0078] Furthermore, the near-infrared emitting device 10 in this embodiment is not limited to having Figure 3 The optical component shown in (a) can be configured in any way as long as it emits output light with the aforementioned characteristic spectral distribution. Furthermore, the spectral distribution of the output light emitted from the near-infrared light-emitting device 10 of this embodiment is not limited to... Figure 4 The spectroscopic distribution is shown.

[0079] [Biobiotechnology Information Detection Device] Next, the biological information detection device of this embodiment will be described. The biological information detection device of this embodiment includes the near-infrared emitting device 10 described above. Figure 5 The diagram below schematically illustrates an example of the biological information detection device of this embodiment. The biological information detection device 20 includes at least a power supply circuit 21, a conductor 22, and a near-infrared light-emitting device 10. The power supply circuit 21 supplies power to the solid-state light-emitting element 1 in the near-infrared light-emitting device 10 through the conductor 22.

[0080] As described above, the near-infrared emitting device 10 converts electrical energy into light energy. The near-infrared emitting device 10 converts at least a portion of the electrical energy supplied from the power supply circuit 21 into light energy, which becomes the output light 23, and outputs it. Furthermore, Figure 5The near-infrared emitting device 10 is configured to emit output light 23 containing at least near-infrared light. Alternatively, the near-infrared emitting device 10 may also be configured to emit output light 23 containing both red light and near-infrared light.

[0081] Figure 5 The biological information detection device 20 also includes a first detector 27A and a second detector 27B. The first detector 27A detects the transmitted light component 25 of the output light 23 emitted from the near-infrared emitting device 10 and illuminating the irradiated body 24. Specifically, the first detector 27A detects the near-infrared light in the transmitted light component 25 that has been transmitted through the irradiated body 24. The second detector 27B detects the reflected light component 26 in the output light 23 emitted from the near-infrared emitting device 10 and illuminating the irradiated body 24. Specifically, the second detector 27B detects the near-infrared light in the reflected light component 26 reflected by the irradiated body 24. Furthermore, the first detector 27A and the second detector 27B can also detect red light in addition to near-infrared light.

[0082] In the biological information detection device 20 configured in this way, output light 23 containing near-infrared light is irradiated onto the irradiated object 24, which is the object of measurement. The transmitted light component 25 that is transmitted through the irradiated object 24 and the reflected light component 26 that is reflected by the irradiated object 24 are detected by the first detector 27A and the second detector 27B. Therefore, the biological information detection device 20 can detect the characteristic information of the irradiated object 24 in which the near-infrared light component is involved.

[0083] Here, the near-infrared emitting device 10 of this embodiment includes at least near-infrared light and is capable of emitting convenient output light 23 to the detector. Therefore, by combining this emitting device and the near-infrared detector, a biological information detection device suitable for industrial use is obtained.

[0084] The first detector 27A and the second detector 27B can use various photodetectors. Specifically, depending on the method of use of the bio-information detection device, quantum photodetectors (photodiodes, phototransistors, photoelectric ICs, CCD image sensors, CMOS image sensors, etc.) that detect the charge generated when light is incident on the PN junction of a semiconductor can be used. In addition, thermal photodetectors (thermoelectric stacks, thermoelectric elements, etc. that utilize the thermoelectric effect) that detect changes in electrical properties caused by the temperature rise due to the heat generated when receiving light, or infrared thin films that are photosensitive, can also be used as photodetectors.

[0085] As the first detector 27A and the second detector 27B, individual elements utilizing photoelectric conversion elements can be used, or imaging elements integrating photoelectric conversion elements can be used. The imaging element can be a one-dimensional linear arrangement or a two-dimensional planar arrangement. A camera can also be used as the first detector 27A and the second detector 27B.

[0086] also, Figure 5 The biological information detection device 20 has both a first detector 27A and a second detector 27B, but the biological information detection device only needs to have at least one of the first detector 27A and the second detector 27B.

[0087] Furthermore, the bio-information detection device of this embodiment can be used for medical purposes, animal medical purposes, and biotechnology purposes. Additionally, the bio-information detection device of this embodiment can be used with any of the following: human, animal, or plant organisms; and it can also be used with any of the following: gas, liquid, or solid.

[0088] Furthermore, the biological information detection device of this embodiment is preferably used as a medical device, treatment device, beauty device, health device, nursing-related device, analysis device, measurement device, or evaluation device.

[0089] For example, for medical and biotechnology development purposes, the biological information detection device of this embodiment can be used for the examination, detection, measurement, evaluation, analysis, interpretation, observation, monitoring, separation, diagnosis, treatment, and purification of 1) blood / body fluids / their components, 2) excretions (urine / feces), 3) proteins / amino acids, 4) cells (including cancer cells), 5) genes / chromosomes / nucleic acids, 6) biological samples / bacteria / specimens / antibodies, 7) biological tissues / organs / blood vessels, and 8) skin diseases / hair loss.

[0090] In addition, for example, for cosmetic and health purposes, the biological information detection device of this embodiment can be used for 1) skin, 2) hair, body hair, 3) oral cavity, teeth, periodontium, 4) ears, nose, 5) vital signs for examination, detection, measurement, evaluation, analysis, interpretation, observation, monitoring, beautification, hygiene, development promotion, health enhancement, diagnosis, etc.

[0091] For example, in nursing purposes, the biological information detection device of this embodiment can be used for excretion confirmation, health status identification, management, monitoring, etc.

[0092] (Supplementary Explanation) The following technology has been disclosed through the above description of the embodiments.

[0093] (Technology 1) A near-infrared emitting device comprising a solid-state emitting element and a wavelength converter including a phosphor, emitting two or more fluorescent components from a light output surface, wherein the two or more fluorescent components include a first fluorescent component and a second fluorescent component arranged side-by-side in sequence from the short wavelength side, the first fluorescent component and the second fluorescent component being fluorescence based on electronic energy transitions of transition metal ions, wherein in the spectral shape of the first fluorescent component, the slope of the long wavelength region from the fluorescence peak of the first fluorescent component is steeper than the slope of the short wavelength region, and in the spectral shape of the second fluorescent component, the slope of the short wavelength region from the fluorescence peak of the second fluorescent component is steeper than the slope of the long wavelength region, the luminescence intensity at the long wavelength end of the first fluorescent component is 10% of the maximum luminescence intensity of the fluorescence peak of the first fluorescent component and the fluorescence peak of the second fluorescent component, the luminescence intensity at the short wavelength end of the second fluorescent component is 10% of the maximum luminescence intensity, and the second fluorescent component has the fluorescence peak in a wavelength range of 780 nm or higher and 1000 nm or lower.

[0094] Based on this configuration, the intensity balance of the measuring light remains constant regardless of the location of the measured object. Furthermore, the dual-wavelength method enables high-precision quantification of the target substance, thereby significantly blocking the fluorescence components between the first and second fluorescent components, thus suppressing adverse effects such as discomfort to the measured object.

[0095] (Technology 2) A near-infrared light-emitting device having a solid-state light-emitting element and a wavelength converter containing a phosphor, emitting two or more fluorescent components from a light output surface, wherein the near-infrared light-emitting device further has a notch filter that controls the wavelength-converted light converted by the wavelength converter, the fluorescent components having a first fluorescent component on the short wavelength side and a second fluorescent component on the long wavelength side separated by a blocking region controlled by the notch filter, the first fluorescent component and the second fluorescent component being fluorescence based on the electronic energy transition of transition metal ions, the second fluorescent component having a fluorescence peak in the wavelength range of 780 nm and below 1000 nm.

[0096] Based on this configuration, the intensity balance of the measuring light remains constant regardless of the location of the measured object. Furthermore, the dual-wavelength method enables high-precision quantification of the target substance, thereby significantly blocking the fluorescence components between the first and second fluorescent components, thus suppressing adverse effects such as discomfort to the measured object.

[0097] (Technology 3) The near-infrared emitting device according to Technology 1 or 2, wherein, in the spectral shape of the first fluorescent component, when the maximum luminescence intensity is set to 100%, the maximum value of the slope of the long wavelength region from the fluorescence peak of the first fluorescent component is 8% / nm or more, and when the maximum luminescence intensity is set to 100%, the maximum value of the slope of the short wavelength region from the fluorescence peak of the first fluorescent component is less than 8% / nm; in the spectral shape of the second fluorescent component, when the maximum luminescence intensity is set to 100%, the maximum value of the slope of the short wavelength region from the fluorescence peak of the second fluorescent component is 8% / nm or more, and when the maximum luminescence intensity is set to 100%, the maximum value of the slope of the long wavelength region from the fluorescence peak of the second fluorescent component is less than 8% / nm.

[0098] According to this configuration, although the fluorescence component between the first and second fluorescent components is cut off, the intensity of the two measuring lights is increased, thus suppressing adverse effects on the analyte and improving the accuracy of the target substance measurement.

[0099] (Technology 4) The near-infrared emitting device according to any one of Techniques 1 to 3, wherein the first fluorescent component and the second fluorescent component are fluorescence based on electronic energy transitions of the same transition metal ion, and are fluorescence based on dd transitions or fd transitions.

[0100] According to this configuration, the near-infrared fluorescence emitted from the wavelength converter becomes a broad spectral distribution with a large half-width, thus making it easy to obtain the first and second fluorescent components with characteristic spectral distributions.

[0101] (Technology 5) A near-infrared emitting device according to any one of technologies 1 to 4, wherein the wavelength difference between the long wavelength end of the first fluorescent component and the short wavelength end of the second fluorescent component is more than 20 nm and less than 100 nm.

[0102] Based on this composition, the first and second fluorescent components are clearly separated, thus further improving the accuracy of target substance determination based on the dual-wavelength method.

[0103] (Technology 6) A near-infrared emitting device according to any one of Technologies 1 to 5, wherein the two or more fluorescent components are emitted from the same phosphor.

[0104] Based on this configuration, it is easy to obtain fluorescence with a characteristic spectroscopic distribution containing a first fluorescent component and a second fluorescent component, thus making it applicable to the dual-wavelength method.

[0105] (Technology 7) The near-infrared emitting device according to any one of Technologies 1 to 6, wherein the first fluorescent component comprises light components in a wavelength range of 600 nm or more and less than 900 nm.

[0106] According to this configuration, the measuring light on the short wavelength side can be at least one of red light and near-infrared light.

[0107] (Technology 8) The near-infrared emitting device according to any one of Technologies 1 to 7, wherein the transition metal ion is selected from Cr 3+ Cr 4+ Fe 3+ and Eu 2+ At least one of the groups.

[0108] Based on this configuration, it is easy to obtain fluorescence with a characteristic spectroscopic distribution containing a first fluorescent component and a second fluorescent component, thus making it applicable to the dual-wavelength method.

[0109] (Technology 9) A biological information detection device comprising the near-infrared emitting device described in any one of Technologies 1 to 8.

[0110] Based on this configuration, a biological information detection device capable of obtaining biological information with high precision through a dual-wavelength method can be obtained.

[0111] Example The following embodiments will be described in more detail, but the embodiments are not limited to these embodiments.

[0112] [The creation of a light-emitting device] First, fluorescent ceramics were synthesized using a solid-state reaction-based preparation method. Specifically, (Ga) 0.69 ,Sc 0.3 ,Cr 0.01 The fluorescent ceramic with the composition shown in Gd₂O₃ was then synthesized. Furthermore, a fluorescent ceramic composed of Gd₃(Ga₂O₃) was synthesized. 0.97 ,Cr 0.03 )2Ga3O 12 Fluorescent ceramics represented by the composition formula.

[0113] Furthermore, the following compound powders are used as the main raw materials in the synthesis of various fluorescent ceramics.

[0114] Gallium oxide (Ga2O3): Purity 4N, manufactured by Asia Physical Properties Co., Ltd. Scandium oxide (Sc2O3): Purity 3N, manufactured by High Purity Chemical Research Institute, Ltd. Chromium oxide (Cr2O3): Purity 3N, manufactured by High Purity Chemical Research Institute, Ltd. Boric acid (H3BO3): Purity 2N, manufactured by Fujifilm and Koujun Chemical Co., Ltd. Gadolinium oxide (Gd₂O₃): Purity 4N, manufactured by Yttrium Corporation of Japan. First, the raw materials for the fluorescent ceramics were weighed according to the mixing conditions shown in Table 1. Next, the weighed raw materials were placed in the jar of a planetary ball mill, and water and φ3mm alumina balls were added. The raw materials were then wet-mixed using the planetary ball mill. The resulting slurry was then thoroughly dried in a constant temperature bath at 125°C, and then gently pulverized using a mortar and pestle to obtain the raw material mixture powder.

[0115] Next, 1g of the raw material mixture powder obtained in each example was filled into a mold (φ13mm), and then pressed using a manual press at a pressure of 10MPa to form a molded body. Then, each molded body was fired under the firing conditions shown in Table 2 to obtain a sintered body.

[0116] Each sintered body was ground using an automatic grinding machine (model: DAG810, manufactured by DISCO Co., Ltd.) to a film thickness of 100 μm, thereby obtaining each fluorescent ceramic. Finally, each fluorescent ceramic was processed into a size of 3.2 mm × 2.6 mm using an automatic cutting saw (product number: DAD3350, manufactured by DISCO Co., Ltd.).

[0117] Next, commercially available blue LEDs were prepared. The LEB P2MQ, product code LEB P2MQ-GSHQ-23-0, manufactured by amsOSRAM, was used as the blue LED. The light-emitting module was obtained by stacking and mounting the aforementioned fluorescent ceramic on top of the blue LED.

[0118] Next, a notch filter was prepared as an optical component. An OD4.0 notch filter, product code #86-703, manufactured by Edmond Optics, was used as the notch filter. This notch filter has a center wavelength of 830 nm in its blocking region and a full width at half maximum (FWHM) of 42 nm. Furthermore, the reflectivity of the blocking region is above 99%. Additionally, the transmission band outside the blocking region of the notch filter is 625–1100 nm, with a transmittance of above 90%.

[0119] Then, by placing the notch filter on the light-emitting module, the light-emitting device of this example is obtained.

[0120] [Evaluation of Spectroscopic Distribution] The operation of the light-emitting device of the embodiment obtained as described above was confirmed. Specifically, when power (11.37V, 500mA) is applied to the blue LED chip of the light-emitting device, blue light is emitted from the blue LED chip as primary light. Then, a portion of it is absorbed by the Cr contained in the fluorescent ceramic. 3+ Absorption, through Cr 3+ The electron energy transition is converted into light containing near-infrared rays as wavelength-converted light.

[0121] Then, the wavelength-converted light is transmitted through a notch filter, thereby cutting off light near 830nm, and the remaining light is output. The spectral distribution of the light output from the light-emitting device in this example is... Figure 4 The spectroscopic distribution is shown.

[0122] exist Figure 4 In the spectroscopic distribution shown, the fluorescence peak wavelength of the first fluorescent component is 804 nm, and the fluorescence peak wavelength of the second fluorescent component is 857 nm. Furthermore, the short wavelength end of the first fluorescent component is 10% of the intensity of its fluorescence peak, i.e., 713 nm, and the long wavelength end is 10% of the intensity of its fluorescence peak, i.e., 813 nm. Similarly, the short wavelength end of the second fluorescent component is 10% of the intensity of the fluorescence peak of the first fluorescent component, i.e., 847 nm, and the long wavelength end is 10% of the intensity of the fluorescence peak of the first fluorescent component, i.e., 1011 nm.

[0123] Furthermore, when the maximum luminescence intensity of the fluorescence peak of the first fluorescent component is set to 100%, the maximum slope of the long-wavelength region starting from the fluorescence peak of the first fluorescent component is 25.86% / nm. Additionally, when this maximum luminescence intensity is set to 100%, the maximum slope of the short-wavelength region starting from the fluorescence peak of the first fluorescent component is 1.70% / nm.

[0124] Furthermore, when the maximum luminescence intensity of the first fluorescent component is set to 100%, the maximum slope of the short-wavelength region starting from the fluorescence peak of the second fluorescent component is 13.00% / nm. When the maximum luminescence intensity is set to 100%, the maximum slope of the long-wavelength region starting from the fluorescence peak of the second fluorescent component is 2.11% / nm.

[0125] Furthermore, on the short-wavelength side of the first fluorescent component, the wavelength range from the short-wavelength end of the first fluorescent component to the fluorescence peak of the first fluorescent component is 91 nm. Moreover, on the long-wavelength side of the first fluorescent component, the wavelength range from the fluorescence peak of the first fluorescent component to the long-wavelength end of the first fluorescent component is 9 nm.

[0126] Furthermore, on the short-wavelength side of the second fluorescent component, the wavelength range from the short-wavelength end of the second fluorescent component to the fluorescence peak of the second fluorescent component is 10 nm. Furthermore, on the long-wavelength side of the second fluorescent component, the wavelength range from the fluorescence peak of the second fluorescent component to the long-wavelength end of the second fluorescent component is 154 nm.

[0127] Thus, in the output light emitted from the light-emitting device of the embodiment, the slope of the long-wavelength region starting from the fluorescence peak of the first fluorescent component is steeper than the slope of the short-wavelength region, and the slope of the short-wavelength region starting from the fluorescence peak of the second fluorescent component is steeper than the slope of the long-wavelength region. Therefore, by using the dual-wavelength method, the target substance can be quantified with high precision, and the fluorescence component between the first and second fluorescent components can be significantly blocked, thereby suppressing adverse effects such as discomfort to the analyte.

[0128] exist Figure 4 In this study, light with wavelengths above 930 nm is unnecessary light and should not be used for measurement. Therefore, a low-pass filter can be used, for example, to block light with wavelengths above 930 nm.

[0129] The above describes this embodiment, but this embodiment is not limited thereto, and various modifications can be made within the scope of the spirit of this embodiment.

[0130] This document quotes the full contents of Japanese Special Application No. 2023-119019 (application date: July 21, 2023).

[0131] Industrial applicability According to this disclosure, a near-infrared emitting device can be provided that can suppress uneven illumination of the light irradiating the object being measured, even when irradiated with light of two different wavelengths.

[0132] Figure Labels 1. Solid-state light-emitting element 2 Wavelength converter 3. Optical components (notch filter) 10 Near-infrared light-emitting devices

Claims

1. A near-infrared light-emitting device comprising a solid-state light-emitting element and a wavelength converter containing a phosphor, emitting two or more fluorescent components from a light output surface, wherein, The two or more fluorescent components include a first fluorescent component and a second fluorescent component arranged side by side in sequence from the short wavelength side, wherein the first fluorescent component and the second fluorescent component are fluorescence based on the electronic energy transition of transition metal ions. In the spectral shape of the first fluorescent component, the slope of the long-wavelength region starting from the fluorescence peak of the first fluorescent component is steeper than the slope of the short-wavelength region; in the spectral shape of the second fluorescent component, the slope of the short-wavelength region starting from the fluorescence peak of the second fluorescent component is steeper than the slope of the long-wavelength region. The luminescence intensity at the long wavelength end of the first fluorescent component is 10% of the maximum luminescence intensity of the fluorescence peak of the first fluorescent component and the fluorescence peak of the second fluorescent component, and the luminescence intensity at the short wavelength end of the second fluorescent component is 10% of the maximum luminescence intensity. The second fluorescent component has the fluorescence peak in the wavelength range of 780 nm and below 1000 nm.

2. A near-infrared emitting device, comprising a solid-state emitting element and a wavelength converter containing a phosphor, emitting two or more fluorescent components from a light output surface, wherein, The near-infrared emitting device also includes a notch filter for controlling the wavelength-converted light generated by the wavelength converter. The fluorescence component, separated by a blocking region controlled by the notch filter, has a first fluorescence component on the short wavelength side and a second fluorescence component on the long wavelength side. The first and second fluorescence components are fluorescence based on the electronic energy transitions of transition metal ions. The second fluorescent component has a fluorescence peak in the wavelength range of above 780 nm and below 1000 nm.

3. The near-infrared emitting device according to claim 1 or 2, wherein, In the spectral shape of the first fluorescent component, when the maximum luminescence intensity of the fluorescence peaks of the first and second fluorescent components is set to 100%, the maximum slope of the long-wavelength region starting from the fluorescence peak of the first fluorescent component is 8% / nm or more, and when the maximum luminescence intensity is set to 100%, the maximum slope of the short-wavelength region starting from the fluorescence peak of the first fluorescent component is less than 8% / nm. In the spectral shape of the second fluorescent component, when the maximum luminescence intensity is set to 100%, the maximum slope of the short-wavelength region starting from the fluorescence peak of the second fluorescent component is greater than 8% / nm, and when the maximum luminescence intensity is set to 100%, the maximum slope of the long-wavelength region starting from the fluorescence peak of the second fluorescent component is less than 8% / nm.

4. The near-infrared emitting device according to any one of claims 1 to 3, characterized in that: The first fluorescent component and the second fluorescent component are fluorescence based on the electronic energy transition of the same transition metal ion, that is, fluorescence based on dd transition or fd transition.

5. The near-infrared emitting device according to claim 1, wherein, The wavelength difference between the long wavelength end of the first fluorescent component and the short wavelength end of the second fluorescent component is greater than 20 nm and less than 100 nm.

6. The near-infrared emitting device according to any one of claims 1 to 5, wherein, The two or more fluorescent components are emitted from the same phosphor.

7. The near-infrared emitting device according to any one of claims 1 to 6, wherein, The first fluorescent component contains light components in the wavelength range of 600 nm and above and less than 900 nm.

8. The near-infrared emitting device according to any one of claims 1 to 7, wherein, The transition metal ion is selected from Cr. 3+ Cr 4+ Fe 3+ and Eu 2+ At least one of the groups.

9. A biological information detection device, comprising the near-infrared emitting device according to any one of claims 1 to 8.

Images