Spectrometer employing pump light source and fluorescent radiation

Abstract

A spectrometer apparatus (110) and method of obtaining spectroscopy information about at least one object (112) are disclosed. The spectrometer device (110) comprises: i. At least one light source (114) for generating illumination light (116) for illuminating the object (112), the light source (114) comprising at least one light emitting diode (118) and at least one luminescent material (120) for converting primary light generated by the light emitting diode (118) into secondary light, the illumination light (116) comprises, at least in part, the primary light and the secondary light; ii. At least one broadband detector (128) for detecting detection light (130) from the object (112) within a spectral range comprising, at least in part, a spectral range of the primary light and the secondary light, the broadband detector (128) is configured to generate at least one primary detector signal upon detection of the detection light (130) within the spectral range of the primary light, where the broadband detector (128) is further configured to generate at least one secondary detector signal upon detection of the detection light (130) within the spectral range of the secondary light; and iii. At least one evaluation unit (136) for evaluating at least one of the primary detector signal and the secondary detector signal generated by the broadband detector (128) and for determining spectroscopy information about the object (112) from the at least one of the primary detector signal and the secondary detector signal.

Description

Technical Field

[0001] This invention relates to a spectrometer apparatus and method for obtaining spectroscopic information about at least one object. The invention further relates to a computer program and a computer-readable storage medium for performing the method. Such an apparatus and method can generally be used for research or monitoring purposes, particularly in the infrared (IR) spectral region, especially in the near-infrared (NIR) spectral region, and in the visible (VIS) spectral region, for example in a spectral region that allows for the simulation of human color vision. However, other applications are also possible. Background Technology

[0002] Spectrometers are known to be efficient tools for obtaining information about the spectral properties of an object when it emits, irradiates, reflects, and / or absorbs light. Therefore, spectrometers can aid in the analysis of samples or other tasks where information about the spectral properties of an object is of interest.

[0003] Typically, in spectrometer equipment, spectral information is obtained via one or more detectors and one or more wavelength-selective optical elements (such as one or more dispersive optical elements, filters (such as bandpass filters), prisms, gratings, interferometers, etc.). Detectors can include any type of photosensitive element, such as one or more single-pixel or multi-pixel detectors, line detectors, or array detectors with one-dimensional or two-dimensional pixel arrays. Furthermore, spectrometer equipment can include one or more light sources. Therefore, in spectroscopy, tunable light sources (such as lasers) and / or broadband emission light sources (such as halogen gas-filled bulbs and / or heated filaments) are commonly used. However, additionally or alternatively, other light sources, such as light-emitting diodes (LEDs), have been proposed for the visible and near-infrared spectral regions.

[0004] As an example, US 2010 / 208261 A1 describes an apparatus for determining at least one optical property of a sample. The apparatus includes a tunable excitation source for applying excitation light to the sample. The apparatus also includes a detector for detecting the detection light emitted from the sample. The excitation source includes an array of light-emitting diodes (LEDs), which is at least partially configured as a monolithic LED array. The monolithic LED array includes at least three LEDs, each having a different emission spectrum.

[0005] US 8,164,050 B2 describes a multichannel light source assembly for downhole spectroscopy, which has individual light sources that generate optical signals spanning wavelengths across a certain spectral range. A combining component optically combines the generated signals into a combined signal, while a routing component splits the combined signal into a reference channel and a measurement channel. A control circuitry system electrically coupled to the light sources modulates each of the light sources at a unique or independent frequency during operation.

[0006] Furthermore, US 7,061,618 B2 describes integrated spectroscopic systems in which, in some examples, an integrated tunable detector is provided using one or more Fabry-Perot tunable filters. Other examples use integrated tunable light sources that combine one or more diodes (such as superluminescent diodes (SLEDs)) with Fabry-Perot tunable filters or standard gauges.

[0007] Furthermore, US 5,475,221 A describes an optical device that uses an array of light-emitting diodes controlled by a multiplexing scheme to replace conventional broadband light sources in devices such as spectrometers.

[0008] Furthermore, US 2021 / 293620 A1 discloses a spectrometer comprising: an illumination device for illuminating a spectral measurement region; a detection unit for detecting electromagnetic radiation from the spectral measurement region; and a spectral element arranged in a beam path between the illumination device and the detection unit. The illumination device includes: a light-emitting diode having a first center wavelength, the light-emitting diode being designed to emit first electromagnetic radiation having a first spectrum; and a light-emitting element for converting a first component of the first electromagnetic radiation having the first spectrum into second electromagnetic radiation having a second spectrum. The first center wavelength is 550 nm or 3000 nm, or has a value between 550 nm and 3000 nm. The first spectrum and the second spectrum overlap.

[0009] Furthermore, EP 3 961 826 A1 discloses a light-emitting device comprising: a light source configured to emit primary light; a first phosphor that absorbs the primary light and converts it into first wavelength-converted light with a wavelength longer than the primary light; and a second phosphor that absorbs the primary light and converts it into second wavelength-converted light with a wavelength longer than the primary light. The first wavelength-converted light is fluorescence having a light component across the entire wavelength range of 700 nm (or greater) to 800 nm (or less). The second wavelength-converted light is fluorescence with a peak, wherein the fluorescence intensity exhibits a maximum value in the wavelength range of 380 nm (or greater) to less than 700 nm. The afterglow time of the first wavelength-converted light is 1 / 10 longer than the afterglow time of the second wavelength-converted light.

[0010] Despite the numerous advantages of known methods and devices, several technical challenges remain in the field of spectroscopy and spectroscopic equipment, particularly in the near-infrared range. Spectrometer systems using a combination of LEDs and phosphorescent coatings as light sources may suffer from low conversion efficiency in certain wavelength ranges (e.g., the infrared range), and thus may exhibit significant illumination outside the intended target wavelength range. Consequently, optical power in this wavelength range is often wasted because spectroscopic information cannot be obtained from these wavelengths. Furthermore, compared to industrial applications where dedicated hardware can be used for specific measurement settings, consumer-grade spectroscopy is expected to cover a wide range of applications, specifically to gain appeal in the mass market. Many of these applications may require the study of spatially heterogeneous materials, which typically possess different optical properties, such as varying penetration depths across different wavelength ranges. It is often necessary to obtain spectroscopic information about the depth of these samples, also known as their spatial distribution.

[0011] However, the technical challenges may stem from the fact that in the consumer spectroscopy field, compact integrated spectrometer devices (such as those integrated into wearable devices) can only be equipped with limited resources (e.g., a single emitter and detector type) to cover the desired range of applications. Known solutions use emission spectra defined for a single specific application, such as using a single-chip white LED, which specifically may include a mixture of blue pump light and the complementary color of the yellow fluorescence spectrum from a phosphor to generate white light. These systems may not be able to handle a wide range of spectroscopic applications. The problem to be solved

[0012] Therefore, it is desirable to provide methods and apparatus that at least partially address the aforementioned technical challenges and at least substantially avoid the drawbacks of known methods and apparatuses. In particular, an object of the present invention is to provide a spectrometer apparatus and method for obtaining spectroscopic information about at least one object, which is capable of handling spectroscopic applications in the consumer spectroscopy field. Summary of the Invention

[0013] This problem is solved by a spectrometer apparatus for obtaining spectroscopic information about at least one object, a method for obtaining spectroscopic information about at least one object, and a computer program and computer-readable storage medium for performing the method, having the features of the independent claims. Advantageous embodiments that can be implemented independently or in any arbitrary combination are set forth in the dependent claims and throughout the specification.

[0014] In a first aspect of the invention, a spectrometer apparatus for obtaining spectroscopic information about at least one object is disclosed.

[0015] As used herein, the term "spectrometer device" is a broad term and will be given its common and conventional meaning to those skilled in the art, and is not limited to a specific or custom meaning. Specifically, the term may refer to, but is not limited to, an optical device configured to acquire at least one spectral information item about at least one object. Specifically, at least one spectral information item may refer to at least one optical characteristic or optically measurable characteristic determined as a function of wavelength for one or more different wavelengths. More specifically, the optical characteristic or optically measurable characteristic and at least one spectral information item may relate to at least one characteristic characterizing at least one of transmission, absorption, reflection, and emission of at least one object itself or after exposure to external light. At least one optical characteristic may be determined for one or more wavelengths. The spectrometer device may specifically be configured to record signal strengths about corresponding wavelengths or partitions (e.g., wavelength intervals) of the spectrum, wherein the signal strength may specifically be provided as an electrical signal that can be used for further evaluation.

[0016] As an example, a spectrometer device may be, or may include, a device that allows the measurement of at least one spectrum (e.g., for measuring spectral flux, specifically as a function of wavelength or detection wavelength). As an example, the spectrum may be acquired in absolute or relative units (e.g., relative to at least one reference measurement). Thus, as an example, the acquisition of at least one spectrum may specifically be performed for the measurement of spectral flux (in W / nm) or spectrum (in 1) relative to at least one reference material, which may describe the material's properties (e.g., reflectance as a function of wavelength). Additionally or alternatively, the reference measurement may be based on a reference light source, an optical reference path, a calculated reference signal (e.g., a calculated reference signal from a document), and / or a reference device.

[0017] Specifically, at least one spectrometer device may be a diffuse reflectance spectrometer device configured to acquire spectral information from light diffusely reflected by at least one object (e.g., at least one sample). Additionally or alternatively, at least one spectrometer device may be or may include an absorption spectrometer and / or a transmission spectrometer. In particular, measuring the spectrum with the spectrometer device may include measuring absorption in a transmission configuration. Specifically, the spectrometer device may be configured to measure absorption in a transmission configuration. However, as outlined above, other types of spectrometer devices are also feasible.

[0018] Specifically, and as will be further detailed below, at least one spectrometer device may include at least one light source, which, as an example, may be at least one of a tunable light source, a light source having at least one fixed emission wavelength, and a broadband light source. As will be further detailed below, the spectrometer device further includes at least one detector device configured to detect light, such as at least one of light transmitted, reflected, or emitted from at least one object. As will be further detailed below, the spectrometer device may further include at least one wavelength selection element, such as at least one of a grating, a prism, or a filter (e.g., a length-variable filter having varying transmission characteristics on its lateral extension). The wavelength selection element can be used to separate the incident light into spectra comprising wavelength signals, the corresponding intensities of which are determined by employing a detector (e.g., a detector having a detector array described in more detail below).

[0019] The spectrometer device can specifically be a portable spectrometer device. As used herein, the term "portable" is a broad term and will be given its common and conventional meaning to those skilled in the art, and is not limited to a specific or customized meaning. The term can specifically refer to, but is not limited to, the characteristic that at least one object can be moved manually (e.g., by a single user). Specifically, the weight of an object characterized by the term "portable" may not exceed 10 kg, specifically 5 kg, more specifically 1 kg, or even 500 g. Additionally or alternatively, the dimensions of an object characterized by the term "portable" may allow the object to extend no more than 0.3 m in any dimension, specifically no more than 0.2 m in any dimension. Specifically, the volume of the object may not exceed 0.03 m³, specifically 0.01 m³, more specifically 0.001 m³, or even 500 mm. 3Specifically, as an example, a portable spectrometer device may have dimensions of, for example, 10 mm × 10 mm × 5 mm. Specifically, the portable spectrometer device may be part of or attachable to a mobile device, such as a laptop computer, tablet computer, mobile phone (e.g., smartphone), smartwatch, and / or wearable computer (also referred to as a "wearable device," such as a human-worn computer (e.g., a wristband or watch)). Specifically, the weight of the spectrometer device, specifically the portable spectrometer device, may be in the range of 1 g to 100 g, more specifically in the range of 1 g to 10 g.

[0020] As used herein, the term "spectral information" (also referred to as "spectral information" or "spectral information item") is a broad term and will be given its common and conventional meaning to those skilled in the art and is not limited to a specific or customary meaning. Specifically, the term may refer to, but is not limited to, information items relating to, at least one object and / or radiation emitted by, at least one object, characterizing at least one optical property of that object, and more specifically, characterizing, for example, at least one information item qualitatively and / or quantitatively representing, at least one of the transmission, absorption, reflection, and emission of that at least one object. As an example, at least one spectral information item may include at least one intensity information, such as information regarding the intensity of at least one type of light transmitted, absorbed, reflected, or emitted by the object, the intensity being, for example, a function of wavelength or a subrange of wavelength within one or more wavelengths (e.g., within a wavelength range). Specifically, the intensity information may correspond to, or be derived from, a signal intensity (specifically an electrical signal) recorded by a spectrometer device in relation to the wavelength or wavelength range of the spectrum.

[0021] Specifically, a spectrometer device can be configured to acquire at least one spectrum or at least a portion of a spectrum of the detection light propagating from an object to the spectrometer. The spectrum can be given in radiometric units describing the spectral flux, for example, in watts per nanometer (W / nm), or in other units, such as as a function of the wavelength of the detection light. Thus, a spectrum can describe the optical power of light, for example, within a specific wavelength band in the NIR spectral range. A spectrum can include one or more optical variables that vary with wavelength, such as power spectral density, electrical signals obtained through optical measurements, etc. As an example, a spectrum can indicate the power spectral density and / or spectral flux of an object (e.g., a sample), for example, relative to a reference sample, such as the transmittance and / or reflectance of the object (specifically, the sample).

[0022] As an example, a spectrum may include at least one measurable optical variable or characteristic of the detection light and / or object, which specifically varies with the illumination light and / or detection light. As an example, at least one measurable optical variable or characteristic may include at least one radiometric quantity, such as at least one of spectral density, power spectral density, spectral flux, radiant flux, radiant intensity, spectral radiant intensity, irradiance, and spectral irradiance. Specifically, as an example, a spectrometer device (specifically a detector) may measure in watts per square meter (W / m²). 2 Irradiance is measured in units of watts per square meter per nanometer (W / m²). 2 Spectral irradiance is measured in watts per nanometer (W / nm). Based on the measured quantities, the spectral flux in watts per nanometer (W / nm) and / or the radiative flux in watts (W) can be determined (e.g., calculated) by taking into account the area of ​​the detector.

[0023] As used herein, the term "object" is a broad term and will be given its common and conventional meaning to those skilled in the art, and is not limited to a particular or customary meaning. The term may specifically refer to, but is not limited to, any body selected from living and inanimate objects. Thus, by way of example, at least one object may include one or more articles and / or one or more parts of articles, wherein at least one article or at least one part thereof may include at least one component that can provide a spectrum suitable for study. Additionally or alternatively, an object may be or may include one or more organisms and / or one or more parts thereof, such as one or more body parts of a human (e.g., a user) and / or an animal. Specifically, an object may include at least one sample that can be fully or partially analyzed by spectroscopic methods. By way of example, an object may be or may include at least one of the following: human or animal skin; edible matter, such as fruit; plastics and textiles.

[0024] The spectrometer equipment includes:

[0025] i. At least one light source for generating illumination light for illuminating the object, the light source comprising at least one light-emitting diode and at least one light-emitting material for converting primary light generated by the light-emitting diode into secondary light, wherein the illumination light comprises at least partially the primary light and the secondary light;

[0026] ii. At least one broadband detector for detecting detection light from the object in a spectral range that at least partially includes the spectral ranges of the primary light and the secondary light, wherein the broadband detector is configured to generate at least one primary detector signal when the detection light is detected in the spectral range of the primary light, and wherein the broadband detector is further configured to generate at least one secondary detector signal when the detection light is detected in the spectral range of the secondary light; and

[0027] iii. At least one evaluation unit, the at least one evaluation unit being used to evaluate at least one of the primary detector signal and the secondary detector signal generated by the broadband detector, and to determine spectroscopic information about the object based on at least one of the primary detector signal and the secondary detector signal.

[0028] As used herein, the term "light" is a broad term and will be given its common and conventional meaning to those skilled in the art and is not limited to a particular or customary meaning. Specifically, the term may refer to, but is not limited to, electromagnetic radiation in one or more of the infrared, visible, and ultraviolet spectral ranges. In this document, the term "ultraviolet spectral range" generally refers to electromagnetic radiation with wavelengths from 1 nm to 380 nm, preferably from 100 nm to 380 nm. Further, in part according to the standard ISO-21348, the effective version of this document as of the date of this document, the term "visible spectral range" generally refers to the spectral range from 380 nm to 760 nm. The term "infrared spectral range" (IR) generally refers to electromagnetic radiation from 760 nm to 1000 µm, wherein the range from 760 nm to 1.5 µm is generally referred to as the "near-infrared spectral range" (NIR), the range from 1.5 µm to 15 µm is referred to as the "mid-infrared spectral range" (MidIR), and the range from 15 µm to 1000 µm is referred to as the "far-infrared spectral range" (FIR). Preferably, the light used for the typical purposes of this invention is light in the infrared (IR) spectral range, more preferably light in the near-infrared (NIR) and / or mid-infrared (MidIR) spectral range, especially light with wavelengths of 1 µm to 5 µm, preferably 1 µm to 3 µm. This is because many material properties or properties relating to the chemical composition of many objects can be obtained from the near-infrared spectral range. However, it should be noted that spectral analysis in other spectral ranges is also applicable and within the scope of this invention.

[0029] As used herein, the term "light source" is a broad term and will be given its common and conventional meaning to those skilled in the art, and is not limited to any particular or custom meaning. Specifically, the term may refer to, but is not limited to, any device configured to generate or provide light in the sense defined above. A light source may specifically be or may include at least one electric light source, such as an electrically driven light source. The light source may be part of a spectrometer device within its housing. Alternatively or additionally, the at least one light source may also be arranged externally to the housing, for example, as a separate light source. The light source may be arranged separately from the object and illuminate the object from a distance.

[0030] In spectroscopy, it is important to distinguish between various light sources and optical paths. In the context of this invention, the nomenclature used here refers firstly to light propagating from a light source to an object as "illuminating light" (or "illumination light"). Secondly, light propagating from the object to a detector is referred to as "detection light." Detection light can include at least one of the following: illuminating light reflected by the object, illuminating light scattered by the object, illuminating light transmitted by the object, and luminescent light generated by the object (e.g., phosphorescence or fluorescence generated by the object after optical, electrical, or acoustic excitation by illuminating light). Therefore, detection light can be generated directly or indirectly by illuminating the object with illuminating light.

[0031] As used herein, the term "irradiation" is a broad term and will be given its common and conventional meaning to those skilled in the art, and is not limited to a specific or customary meaning. Specifically, the term may refer to, but is not limited to, the process of exposing at least one element to light.

[0032] Furthermore, as will be detailed below, a distinction can be made between various light sources (such as primary and secondary light sources) within the light source itself. Therefore, as will be further detailed below, "primary light" (also called "pump light") can be generated by a primary light source (such as at least one light-emitting diode) and subsequently transformed into "secondary light," for example, through light conversion (e.g., through a luminescent material, such as one or more phosphor materials). As outlined above, illumination light comprises at least part of primary and secondary light. Specifically, illumination light can include those portions of the primary light generated by the light-emitting diode that are not converted into secondary light by the luminescent material (e.g., due to the low conversion efficiency of the luminescent material) as well as the secondary light.

[0033] As outlined above, the light source includes at least one light-emitting diode and at least one light-emitting material for converting primary light generated by the light-emitting diode into secondary light.

[0034] As used herein, the term "light-emitting diode" or simply "LED" is a broad term and will be given its common and conventional meaning to those skilled in the art, and is not limited to any particular or custom meaning. Specifically, the term may refer to, but is not limited to, optoelectronic semiconductor devices capable of emitting light when an electric current flows through them. Optoelectronic semiconductor devices can be configured to generate light due to one or more of various physical processes, including spontaneous emission, induced emission, decay of metastable excited states, etc. Thus, by way of example, a light-emitting diode may include one or more of the following: a light-emitting diode based on spontaneous emission (particularly an organic light-emitting diode), a superluminescent light-emitting diode (sLED), or a laser diode (LD). Hereinafter, without reducing possible embodiments of a light-emitting diode to any of the foregoing physical principles or setups, the abbreviation "LED" will be used for any type of light-emitting diode. Specifically, an LED may include at least two layers of semiconductor material, wherein light can be generated at at least one interface between the at least two semiconductor material layers, specifically due to the recombination of positive and negative charges (e.g., electron-hole recombination). The at least two semiconductor material layers can have different electrical properties; for example, at least one of these layers may be an n-doped semiconductor material, and at least one of these layers may be a p-doped semiconductor material. Therefore, as an example, an LED may include at least one pn junction and / or at least one pin structure. However, it should be noted that other device structures are also feasible. The at least one semiconductor material may specifically be or may include at least one inorganic semiconductor material. However, it should be noted that organic semiconductor materials may be used additionally or alternatively.

[0035] Typically, as will be further elaborated below, an LED converts electric current into light, specifically into primary light, and more specifically into blue primary light. Therefore, an LED can specifically be a blue LED. An LED can be configured to generate primary light, also known as "pump light." Therefore, an LED can also be referred to as a "pumped LED." An LED can specifically include at least one LED chip and / or at least one LED die. Therefore, the semiconductor elements of an LED can include bare LED chips.

[0036] Various types of LEDs suitable for generating primary light are known to those skilled in the art and can also be used in this invention. Specifically, pn junction diodes can be used. As an example, one or more LEDs selected from the group consisting of indium gallium nitride (InGaN)-based LEDs, GaN-based LEDs, InGaN / GaN alloy-based LEDs, or combinations thereof, and / or other LEDs can be used. Additionally or alternatively, quantum well LEDs, such as one or more InGaN-based quantum well LEDs, can also be used. Additionally or alternatively, superradiative LEDs (sLEDs) and / or quantum cascade lasers can be used.

[0037] As used herein, the term "luminescence" is a broad term and will be given its common and conventional meaning to those skilled in the art, and is not limited to a specific or customary meaning. Specifically, the term may refer to, but is not limited to, the process by which a substance spontaneously emits light not caused by heat. Specifically, luminescence may refer to cold body radiation. More specifically, luminescence can be initiated or excited by irradiation with light, in which case it is also referred to as "photoluminescence." In the context of this invention, the property of a material capable of luminescence is referred to by the adjective "luminescent." At least one luminescent material may specifically be a photoluminescent material, i.e., a material capable of emitting light after absorbing photons or excitation light. Specifically, the luminescent material may have a positive Stokes shift, which generally refers to the fact that the secondary light is redshifted relative to the primary light.

[0038] Therefore, at least one luminescent material can form at least one transducer (also called a light transducer) that converts primary light into secondary light with different spectral characteristics compared to the primary light. Specifically, the spectral width of the secondary light can be greater than that of the primary light, and / or the emission center of the secondary light can be shifted (specifically, redshifted). Specifically, at least one luminescent material can be absorbent in the ultraviolet and / or blue spectral range and emissive in the near-infrared and / or infrared spectral range. Therefore, typically, the luminescent material or transducer can form at least one component of an LED (specifically a phosphor LED) that converts primary light or pump light, specifically in the blue spectral range, into light with a longer wavelength, for example, in the near-infrared or infrared spectral range.

[0039] Various types of conversion and / or luminescence are known and can be used in the context of this invention. Thus, specifically, conversion can occur via dipole-allowed transitions (also known as fluorescence) in the luminescent material, and / or via dipole-forbidden, and therefore longer-lived transitions (also commonly known as phosphorescence) in the luminescent material.

[0040] Therefore, the luminescent material can specifically form at least one transducer or light converter. The luminescent material can form at least one of a conversion sheet, a luminescent coating (specifically a phosphor coating) on ​​an LED, and a phosphor coating on an LED. As an example, the luminescent material may include one or more of the following materials: cerium-doped YAG (YAG:Ce3+ or Y3Al5O12:Ce3+); rare-earth-doped Sialon; copper-aluminum co-doped zinc sulfide (ZnS:Cu,Al).

[0041] The light source may include a phosphor light-emitting diode. Specifically, the LED and the luminescent material together can form a so-called "phosphor LED". Therefore, as used herein, the term "phosphor light-emitting diode" or simply "phosphor LED" is a broad term and will be given its common and conventional meaning to those skilled in the art and is not limited to a specific or custom meaning. The term may specifically refer to, but is not limited to, a combination of at least one light-emitting diode configured to generate primary light or pump light and at least one luminescent material (also referred to as "phosphor") configured to perform light conversion of the primary light generated by the light-emitting diode. Phosphor LEDs can form encapsulated LED light sources, including an LED die (e.g., a blue LED emitting blue pump light) and a phosphor, for example, which is wholly or partially coated on the LED and, by way of example, configured to convert primary light or blue light into light with different spectral characteristics (specifically, into near-infrared light). Typically, phosphor LEDs may be encapsulated in a housing or may be unencapsulated. Therefore, the LED and the at least one luminescent material for performing light conversion of the primary light generated by the light-emitting diode can be specifically housed in a common housing. However, alternatively, LEDs can also be unencapsulated or bare LEDs, which can be completely or partially covered with light-emitting material, for example, by setting one or more layers of light-emitting material on the LED die. Phosphor LEDs can typically form the emitter or light source themselves.

[0042] In a light source (specifically a phosphor LED), at least one luminescent material may be positioned relative to a light-emitting diode (LED) such that heat transfer can occur from the LED to the luminescent material. More specifically, the luminescent material may be positioned such that heat transfer can occur via either or both of thermal radiation and thermal conduction (more preferably thermal conduction). Thus, as an example, the luminescent material may be in thermal and / or physical contact with the LED. As an example, the luminescent material may form one or more coatings or layers that are in contact with or closely adjacent to the LED, such as with one or more of the semiconductor materials of the LED. Consequently, typically, the temperature of the luminescent material and the temperature of the LED can be coupled.

[0043] At least one luminescent material can specifically form at least one layer. Various alternatives for positioning the luminescent material relative to the light-emitting diode are generally feasible, and these alternatives can be used individually or in combination. First, the luminescent material (e.g., at least one layer of the luminescent material, such as a phosphor) can be directly positioned on the light-emitting diode, also known as "direct attachment," for example, with no material between the LED and the luminescent material, or with one or more transparent materials between them, such as one or more transparent materials (particularly transparent to primary light) between the LED and the luminescent material. Thus, as an example, a coating of the luminescent material can be placed directly or indirectly on the LED. Additionally or alternatively, as an example, the luminescent material can form at least one transducer, such as at least one transducer disk, which can be placed on top of the LED, for example, by attaching the transducer to the LED with an adhesive. Additionally or alternatively, the luminescent material can also be placed remotely, such that primary light from the LED must pass through an intermediate optical path before reaching the luminescent material. This placement can also be referred to as "remote placement" or "remote phosphor." Again, as an example, remotely placed luminescent material can form a solid or transducer, such as a disk or transducer disk. Furthermore, in the case of remote placement, the luminescent material can also be a coating. Specifically, the object transmitting light (e.g., a thin glass substrate, a module window) can be coated with a phosphor, and this object includes glass or plastic and / or is made of glass or plastic. Alternatively, the reflective surface can be coated with a phosphor. This can be a flat or rough mirror, which may include a substrate of a highly reflective material (e.g., silicon) and / or be made of a highly reflective material substrate, or a flat or rough surface (e.g., glass or plastic) coated with gold, silver, aluminum, or chromium. One or more optical elements, such as lenses, prisms, gratings, mirrors, apertures, or combinations thereof, can be placed in the intermediate optical path. Therefore, specifically, an optical system with imaging characteristics can be placed in the intermediate optical path, between the LED and the luminescent material. Thus, as an example, the primary light can be focused or converged onto the converter.

[0044] The primary light may be at least partially located in the spectral range of 380 nm to 1000 nm, specifically in the spectral range of 420 nm to 940 nm, more specifically in the spectral range of 420 nm to 830 nm, and more specifically in the spectral range of 440 nm to 830 nm. For example, the primary light may be located in the spectral range between a first wavelength and a second wavelength, wherein the first wavelength is selected from 380 nm, 420 nm, and 440 nm, and the second wavelength is selected from 1000 nm, 940 nm, 830 nm, 460 nm, and 455 nm. For example, the LED may include a blue LED having a primary emission range at least partially located in the spectral range of 420 nm to 460 nm, specifically in the spectral range of 440 nm to 455 nm, and more specifically at 440 nm.

[0045] The primary light generated by the light-emitting diode, which can be non-converted into secondary light by the light-emitting material, is at least partially located in the spectral range of 420 nm to 940 nm, more specifically in the spectral range of 420 nm to 830 nm, and even more specifically in the spectral range of 440 nm to 830 nm. For example, the primary light may be located in the spectral range between a first wavelength and a second wavelength, wherein the first wavelength may be selected from 380 nm, 420 nm, and 440 nm, and wherein the second wavelength may be selected from 1000 nm, 940 nm, 830 nm, 460 nm, and 455 nm.

[0046] Secondary light may be at least partially located in the spectral range of 1 µm to 5 µm, specifically in the spectral range of 1.5 μm to 3 μm, and more specifically in the spectral range of 1.5 μm to 2.5 μm. For example, secondary light may be located in the spectral range between a first wavelength and a second wavelength, wherein the first wavelength includes at least one of 1 μm or 1.5 μm, and wherein the second wavelength is selected from 5 μm, 3 μm, and 1.5 μm.

[0047] As outlined above, the spectrometer device includes at least one broadband detector for detecting detection light from an object within a spectral range that at least partially includes primary and secondary light. As used herein, the verb “detect” is a broad term and will be given its common and conventional meaning to those skilled in the art, and is not limited to a specific or customary meaning. Specifically, the term may refer to, but is not limited to, the process of qualitatively and / or quantitatively determining, measuring, and monitoring at least one parameter (e.g., at least one of physical, chemical, and biological parameters). Specifically, physical parameters may be or may include electrical parameters. Therefore, as used herein, the term “detector” is a broad term and will be given its common and conventional meaning to those skilled in the art, and is not limited to a specific or customary meaning. Specifically, the term may refer to, but is not limited to, any device configured for detecting, i.e., qualitatively and / or quantitatively determining, measuring, and monitoring at least one parameter (e.g., at least one of physical, chemical, and biological parameters). The detector can be configured to generate at least one detector signal, more specifically at least one electrical detector signal, such as an analog and / or digital detector signal, which provides information about at least one parameter measured by the detector. The detector signal can be provided directly or indirectly to the evaluation unit, allowing the detector and the evaluation unit to be directly or indirectly connected. The detector signal can be used as a "raw" detector signal and / or can be processed or preprocessed (e.g., by filtering) before further use. Therefore, the detector can include at least one processing device and / or at least one preprocessing device, such as at least one of an amplifier, an analog-to-digital converter, an electrical filter, and a Fourier transform.

[0048] As used herein, the term "broadband detector" is a broad term and will be given its common and conventional meaning to those skilled in the art, and is not limited to a specific or custom meaning. Specifically, the term may refer to, but is not limited to, at least one detector configured to detect light in more than one spectral range of the infrared, visible, and ultraviolet spectral ranges. Specifically, a broadband detector may be configured to detect detection light in at least a first portion of the visible spectral range and a second portion of the infrared spectral range, wherein the second portion may preferably be adjacent to the first portion; however, it may also be feasible to use a second portion that is separable from the first portion. A broadband detector may be configured to detect detection light from an object in a spectral range of 200 nm to 5 µm, preferably 300 nm to 3 µm, more preferably 400 nm to 2.5 µm.

[0049] A broadband detector can be configured to detect light propagating from an object to a spectrometer device, or more specifically, to a detector within the spectrometer device; this light is referred to as "detection light" according to the aforementioned nomenclature. Therefore, specifically, a broadband detector can be, or may include, at least one optical detector. The optical detector can be configured to determine at least one optical parameter, such as the intensity and / or power of light irradiating at least one sensitive region of the broadband detector. More specifically, the optical detector may include at least one photosensitive element and / or at least one optical sensor, such as at least one of a photodiode, photovoltaic cell, photoresistor, phototransistor, thermopile sensor, photoacoustic sensor, pyroelectric sensor, photomultiplier, and calorimeter. Therefore, a broadband detector can be configured to generate at least one detector signal, more specifically, at least one electrical detector signal in the aforementioned sense, which provides information about at least one optical parameter (such as the power and / or intensity of light irradiating the broadband detector or a sensitive region of the broadband detector).

[0050] A broadband detector may include a single optical sensing element or region or multiple optical sensing elements or regions. Specifically, a broadband detector may be or may include at least one detector array (more specifically, an array of photosensitive elements), as will be further detailed below. Each photosensitive element may include at least a photosensitive region adapted to generate an electrical signal based on the intensity of the incident light, wherein the electrical signal may be specifically provided to an evaluation unit, as will be further detailed below.

[0051] The photosensitive region comprised of each optical sensing element can be, in particular, a single, uniform photosensitive region configured to receive incident light illuminating the individual optical sensing element. However, other arrangements of the optical sensing elements are also conceivable.

[0052] An array of optical sensing elements can be designed to generate detector signals, preferably electronic signals, associated with the intensity of incident light illuminating each optical sensing element. The detector signals can be analog and / or digital signals. Accordingly, electronic signals from adjacent pixelated sensors can be generated simultaneously or sequentially over time. For example, during line or row scanning, a series of electronic signals corresponding to a series of individual optical sensing elements arranged in a row can be generated. Furthermore, these individual optical sensing elements can preferably be active pixel sensors, adapted to amplify the electronic signals before providing them to the evaluation unit. For this purpose, the broadband detector may include one or more signal processing devices, such as one or more filters and / or analog-to-digital converters, for processing and / or preprocessing the electronic signals.

[0053] In cases where the broadband detector comprises an array of optical sensing elements, as an example, the broadband detector can be selected from any known pixel sensor, particularly from pixelated organic camera elements, preferably pixelated organic camera chips, or from pixelated inorganic camera elements, preferably pixelated inorganic camera chips, more preferably from CCD chips or CMOS chips, which are types commonly used in various types of cameras. Alternatively, the broadband detector can typically be or include a photoconductor, particularly an inorganic photoconductor, especially PbS, PbSe, InSb, or HgCdTe. As another alternative, the broadband detector can be or include a photodiode, particularly a photodiode comprising at least one of Si, Ge, InGaAs, or epitaxial InGaAs. As yet another alternative, the broadband detector can be or include at least one of a pyroelectric element, a radiation calorimeter element, or a thermopile detector element. Therefore, camera chips with a matrix of 1 × N pixels or M × N pixels can be used here, where, as an example, M can be <10, and N can be in the range of 1 to 50, preferably from 2 to 20, more preferably from 5 to 10. Furthermore, monochrome camera elements, preferably monochrome camera chips, can be used, wherein the monochrome camera elements can be selected differently for each optical sensor, particularly based on varying wavelengths on a series of optical sensors.

[0054] Therefore, the array can be adapted to provide multiple electrical signals, which can be generated by the photosensitive regions of the optically sensitive elements included in the array. The electrical signals provided by the array of the spectrometer device can be forwarded to the evaluation unit.

[0055] As used herein, the term "primary detector signal" is a broad term and will be given its common and conventional meaning to those skilled in the art and is not limited to a specific or custom meaning. Specifically, the term may refer to, but is not limited to, at least one detector signal generated by a broadband detector when detecting detection light within the spectral range of the primary light.

[0056] Similarly, as used herein, the term "secondary detector signal" is a broad term and will be given its common and conventional meaning to those skilled in the art and is not limited to a specific or custom meaning. Specifically, the term may refer to, but is not limited to, at least one detector signal in the foregoing sense, generated by a broadband detector when detecting detection light within the spectral range of the secondary light.

[0057] A broadband detector may include multiple detector elements, such as multiple optically sensitive elements as outlined above, for detecting detection light within the spectral range of primary and secondary light. For example, a broadband detector may include a pixelated broadband detector comprising multiple optically sensitive pixels or elements, as described in detail above. For instance, a broadband detector may include at least one first detector element for detecting detection light within the spectral range of primary light, and at least one second detector element for detecting detection light within the spectral range of secondary light. Specifically, the first detector element may be configured to generate a primary detector signal upon detection of detection light within the spectral range of primary light. The second detector element may be configured to generate a secondary detector signal upon detection of detection light within the spectral range of secondary light. Each detector element may include at least one photosensitive material selected from PbS, PbSe, InSb, or HgCdTe. The detector elements among the multiple detector elements may include the same photosensitive material, or alternatively, different photosensitive materials. Different materials for the detector elements may be specifically used where different sensitivities are envisioned in different wavelength ranges and / or different use cases are envisioned.

[0058] Alternatively, the broadband detector may be a single detector comprising at least one photosensitive material selected from PbS, PbSe, InSb, or HgCdTe. As another alternative, the broadband detector may be a single detector comprising a photodiode (especially a photodiode having at least one of Si, Ge, InGaAs, or epitaxial InGaAs).

[0059] The spectrometer device may further include at least one driving unit for electrically driving a light source. As used herein, the term "driving" is a broad term and will be given its common and conventional meaning to those skilled in the art and is not limited to a specific or custom meaning. The term may specifically refer to, but is not limited to, the process of providing at least one or more of a control parameter and / or electrical power to another device. Therefore, as used herein, the term "driving unit" is a broad term and will be given its common and conventional meaning to those skilled in the art and is not limited to a specific or custom meaning. The term may specifically refer to, but is not limited to, any device or combination of devices configured to provide at least one or more of a control parameter and / or electrical power to another device (e.g., in this example, to at least one light source). For example, the driving unit may specifically be configured to perform at least one operation of measuring and controlling one or more electrical parameters of the electrical power supplied to the light source (specifically, to at least one light-emitting diode). As an example, the driving unit may be configured to supply current to the LED, specifically to control the current through the LED. Wherein, as an example, the driving unit may be configured to adapt and measure the voltage supplied to the LED, which is required to achieve a specific current through the LED. The driving unit may specifically include one or more of the following: a current source, a voltage source, a current measuring device (e.g., an ammeter), a voltage measuring device (e.g., a voltmeter), and a power measuring device. Specifically, the driving unit may include at least one current source for providing at least one predetermined current to the LED, wherein the current source may be specifically configured to adjust or control the voltage applied to the LED to generate the predetermined current. As an example, the driving unit may include one or more electrical components (e.g., integrated circuits) for driving the light source. The driving unit may be wholly or partially integrated into the light source, or it may be separate from the light source.

[0060] The driving unit can be configured to drive a light-emitting diode at at least one driving frequency. As used herein, the term "driving frequency" is a broad term and will be given its common and conventional meaning to those skilled in the art and is not limited to a specific or custom meaning. Specifically, the term may refer to, but is not limited to, a quantitative measure of the number of driving repetitions of a light source per unit time. Specifically, the driving frequency may indicate the number of driving repetitions of the light source per second. Driving a light source (i.e., the process of providing the light source with at least one or both of a control parameter and / or electrical power, wherein a first value causes the light source to emit light and a second value causes the light source not to emit light) can be referred to as a single driving repetition.

[0061] Furthermore, the driving frequency can exceed the time constant of the luminescent material. The reciprocal of. As used herein, the term "time constant" is a broad term and will be given its common and conventional meaning to those skilled in the art and is not limited to a specific or custom-defined meaning. Specifically, the term may refer to, but is not limited to, a typical time interval describing the reorganization of equilibrium states (particularly the equilibrium state of luminescent materials) when at least one operating parameter is changed. Time constant The time delay can be described as the time interval between the absorption of at least one primary photon by a luminescent material and the emission of at least one secondary photon. This time delay can be represented by the so-called "characteristic time constant". The time constant is used to characterize a process where the rate or probability of a process (such as photon emission) is proportional to the population of one or more states or process states. In these processes, the population typically changes exponentially. The process can be determined Time. For luminescent materials or converters, particularly phosphors, two distinct time constants can exist. First, a first time constant describes the typical time it takes for the emission of the converted light to reach saturation, such as a "growth constant," which can depend on the intensity of the pump light. Second, a second time constant describes the typical time for the afterglow of the luminescent material or converter, such as a "decay constant" or "attenuation." The driving frequency can specifically exceed the reciprocal of the attenuation constant of the luminescent material. Furthermore, the evaluation unit can be configured to distinguish the primary detector signal from the secondary detector signal by demodulation (e.g., using Fourier transform, particularly fast Fourier transform). Therefore, the spectrometer device can be configured to modulate the pulse duration of the light source using the driving unit.

[0062] As outlined above, the spectrometer device includes at least one evaluation unit for evaluating at least one of a primary detector signal and a secondary detector signal. As used herein, the term "evaluation" is a broad term and will be given its common and conventional meaning to those skilled in the art, and is not limited to a specific or custom meaning. Specifically, the term may refer to, but is not limited to, the process of processing at least one first information item to generate at least one second information item. Therefore, as used herein, the term "evaluation unit" is a broad term and will be given its common and conventional meaning to those skilled in the art, and is not limited to a specific or custom meaning. Specifically, the term may refer to, but is not limited to, any device or combination of devices configured to evaluate or process at least one first information item to generate at least one second information item thereof. Therefore, specifically, the evaluation unit may be configured to process at least one input signal and generate at least one output signal thereof. As an example, the at least one input signal may include at least one primary detector signal and at least one secondary detector signal provided directly or indirectly by a broadband detector.

[0063] As an example, the evaluation unit may be or may include one or more integrated circuits (such as one or more application-specific integrated circuits (ASICs)) and / or one or more data processing devices (such as one or more of a computer, digital signal processor (DSP), or field-programmable gate array (FPGA), preferably one or more microcomputers and / or microcontrollers. Additional components may be included, such as one or more preprocessing devices and / or data acquisition devices, such as one or more devices for receiving and / or preprocessing detector signals, such as one or more AD converters and / or one or more filters. Further, the evaluation unit may include one or more data storage devices. Further, the evaluation unit may include one or more interfaces, such as one or more wireless interfaces and / or one or more wired interfaces.

[0064] The evaluation unit may be adapted to execute at least one computer program, such as at least one computer program that performs or supports the information item generation step. As an example, one or more algorithms may be implemented that, by using primary detector signals and secondary detector signals as input variables, can perform a predetermined transformation to obtain spectroscopic information about an object, such as at least one piece of spectroscopic information describing at least one characteristic of the object. For this purpose, the evaluation unit may specifically include at least one data processing device (also called a processor, particularly an electronic data processing device) designed to generate desired information by evaluating the primary detector signals and secondary detector signals. The evaluation unit may use any process to generate the desired information, such as by calculating and / or using at least one stored and / or known relation. Specifically, the evaluation unit may be configured to perform at least one digital signal processing (DSP) technique on the primary detector signals or any secondary detector signals derived therefrom, particularly at least one Fourier transform. Additionally or alternatively, the evaluation unit may be configured to perform one or more other digital signal processing techniques on the primary detector signals or any secondary detector signals derived therefrom, such as windowing, filtering, the Goertzel algorithm, cross-correlation, and autocorrelation. In addition to the primary and secondary detector signals, one or more additional parameters and / or information items may also affect the relationship. This relationship can be determined or determined by empirical, analytical, or semi-empirical methods. As an example, the relationship may include at least one of a model or calibration curve, at least one set of calibration curves, at least one function, or a combination of the mentioned possibilities. One or more calibration curves may be stored, for example, in a data storage device and / or a table as a set of values ​​and their associated function values. However, alternatively or additionally, at least one calibration curve may also be stored, for example, in a parametric form and / or as a functional equation. A separate relationship can be used to process the primary and secondary detector signals into information items. Alternatively, at least one combined relationship for processing the primary and secondary detector signals is feasible. Various possibilities are conceivable, and these possibilities can also be combined.

[0065] The evaluation unit can be specifically configured to evaluate the primary detector signal generated by the broadband detector and to obtain first applied spectroscopic information about the object from the primary detector signal. The first applied spectroscopic information about the object may include at least one of volumetric spectroscopic information about the object and surface spectroscopic information about the object. Additionally or alternatively, the evaluation unit can be configured to evaluate the secondary detector signal generated by the broadband detector and to obtain second applied spectroscopic information about the object from the secondary detector signal. The second applied spectroscopic information about the object may include at least one of volumetric spectroscopic information about the object and surface spectroscopic information about the object. Specifically, the penetration depth of the illumination light into the object may depend on the object itself and / or on the spectral ranges of the primary and secondary light. For example, the object to be analyzed by the spectrometer device may include a user's skin. In this example, the evaluation unit can be specifically configured to evaluate the primary detector signal generated by the broadband detector and to obtain volumetric spectroscopic information about the object. Further, the evaluation unit can be configured to evaluate the secondary detector signal generated by the broadband detector and to obtain surface spectroscopic information about the object.

[0066] For example, the object may contain water, which has strong absorption in the NIR spectral range (e.g., in the spectral range of 1300 nm and higher). Therefore, by positioning the secondary light within this spectral range, surface spectroscopic information about the object can be obtained by evaluating the secondary detector signal, where, specifically, volumetric spectroscopic information may not be available in this wavelength range. Furthermore, the penetration depth of primary light located in a spectral range including wavelengths of 900 nm or smaller may be greater than that of secondary light. Therefore, in this example, volumetric spectroscopic information can be obtained by evaluating the primary detector signal. Volumetric spectroscopic information can provide information about other effects, such as the effect on melanin concentration or skin color in the example analyzing the skin layer.

[0067] As another example, the spectrometer device can be used to employ NIR spectroscopy across different wavelength ranges to address the variability in human skin physiology. The light source can include an LED emitting primary light between 600 nm and 940 nm, specifically between 600 nm and 830 nm. The primary light can be used to pump a luminescent material to convert the primary light into secondary light in a spectral range of 1500 nm or greater, specifically for the measurement of water and / or lipids. Additionally, the primary light can be used to perform pulse oximetry measurements. Primary and secondary detector signals in these wavelength ranges can be generated by using multiple detector elements, for example, using at least one detector element comprising Si for a wavelength of approximately 940 nm, and at least one additional detector element comprising PbS for wavelengths from 1500 nm to 2500 nm. Alternatively, a single broadband detector (specifically a single broadband detector comprising PbS) can be used to detect the light in both wavelength ranges. As an alternative, Si photodiodes can be used as a single broadband detector, specifically for detecting primary light at approximately 440 nm and secondary light at approximately 1100 nm. Since the pump LED can be faster than the luminescent material, pulses applied to the pump LED can be used, allowing the frequency domain information obtained from the Fast Fourier Transform to be simultaneously provided with spectroscopic information from both the primary and second detector signals using a single broadband detector.

[0068] The spectrometer device may further include at least one wavelength-selective element. As used herein, the term "wavelength-selective element" is a broad term and will be given its common and conventional meaning to those skilled in the art and is not limited to a specific or customary meaning. Specifically, the term may refer to, but is not limited to, any optical element that interacts with different spectral portions of incident light in various ways, for example by having at least one wavelength-dependent optical property (such as at least one wavelength-dependent optical property selected from a list consisting of reflectivity, direction of reflection, refractivity, direction of refraction, absorption, transmission, and refractive index).

[0069] The wavelength selection element can be arranged such that the broadband detector generates at least one primary detector signal when detecting detection light within the spectral range of the primary light, and generates at least one secondary detector signal when detecting detection light within the spectral range of the secondary light.

[0070] Wavelength selection by at least one wavelength selection element can be performed in at least one beam path of the illumination light, thereby selecting and / or modifying the illumination wavelength of the object, and / or in the detection beam path of the detection light, thereby selecting and / or modifying the detection wavelength, for example, typically for broadband detectors and / or for each detector element. The wavelength selection element may include at least one of a wavelength selection element disposed in the beam path of the illumination light or a wavelength selection element disposed in the beam path of the detection light.

[0071] The wavelength selection element can be selected from at least one of a tunable wavelength selection element or a wavelength selection element with a fixed transmission spectrum. A wavelength selection element with a fixed transmission spectrum can include at least one filter element, specifically at least one absorption filter element, more specifically a bandpass filter element. A tunable wavelength selection element can include at least one tunable interferometer, specifically at least one of a MEMS Fabry-Perot interferometer and a MEMS Michelson interferometer.

[0072] For example, a wavelength selection element can be arranged in the detection beam path of the detection light. The wavelength selection element can be configured to direct the detection light within the spectral range of the primary light to a first detector element included in the broadband detector, such that the broadband detector detects the detection light within the spectral range of the primary light and thus generates a primary detector signal. The wavelength selection element can be further configured to direct the detection light within the spectral range of the secondary light to a second detector element included in the broadband detector, such that the broadband detector detects the detection light within the spectral range of the secondary light and thus generates a secondary detector signal. Alternatively, the broadband detector can be a single detector as outlined above, and the wavelength selection element can be a tunable wavelength selection element, allowing adjustment of the spectral range to be detected by the broadband detector.

[0073] In another aspect of the invention, a method for obtaining spectroscopic information about at least one object is disclosed.

[0074] The method includes the following steps, which can be performed in a given order. However, different orders are also possible. In particular, one, more than one, or even all method steps may be performed once or repeatedly. Furthermore, these method steps may be performed sequentially, or alternatively, one or more method steps may be performed in a timely overlapping manner or even in a parallel and / or combined manner. The method may further include additional method steps not listed.

[0075] The method includes:

[0076] a) Provide at least one spectrometer device according to the present invention, such as any of the embodiments disclosed above and / or any of the embodiments further detailed below;

[0077] b) Illuminate the object with illumination light generated by the light source, the light source comprising at least one light-emitting diode and at least one light-emitting material for converting primary light generated by the light-emitting diode into secondary light, wherein the illumination light comprises at least partially the primary light and the secondary light;

[0078] c) Detecting detection light from the object within a spectral range that at least partially includes the spectral range of the primary light and the secondary light by using at least one broadband detector, wherein the broadband detector is configured to generate at least one primary detector signal when the detection light is detected within the spectral range of the primary light, and wherein the broadband detector is configured to generate at least one secondary detector signal when the detection light is detected within the spectral range of the secondary light; and

[0079] d) By using the evaluation unit, at least one of the primary detector signal and the secondary detector signal generated by the broadband detector is evaluated, and spectroscopic information about the object is obtained from at least one of the primary detector signal and the secondary detector signal.

[0080] Specifically, the method may include using a spectrometer apparatus according to the present invention (such as any of the embodiments disclosed above and / or any of the embodiments disclosed in further detail below). Therefore, for possible embodiments of the spectrometer apparatus and / or definitions of terms, refer to the description of the spectrometer apparatus as outlined above.

[0081] Step d) may include evaluating the primary detector signal generated by the broadband detector, and obtaining first applied spectroscopic information about the object from the primary detector signal. Specifically, the first applied spectroscopic information about the object may include at least one of volumetric spectroscopic information about the object and surface spectroscopic information about the object.

[0082] Step d) may include evaluating the secondary detector signal generated by the broadband detector, and obtaining second applied spectroscopic information about the object from the secondary detector signal. The second applied spectroscopic information about the object may include at least one of volumetric spectroscopic information about the object and surface spectroscopic information about the object. Specifically, this operating mode of the light source may also be referred to as pulse duration modulation.

[0083] The spectrometer device may further include at least one driving unit for electrically driven light sources. The method may specifically include, in step b), driving a light-emitting diode at at least one driving frequency using the driving unit. The driving frequency may be higher than the time constant of the luminescent material. The reciprocal of the value. The evaluation in step d) may include distinguishing the primary detector signal from the secondary detector signal by demodulation (e.g., by using Fourier transform, especially fast Fourier transform).

[0084] This method can be at least partially computer-implemented, specifically at least step d). Referring to the computer-implemented aspects of the invention, one or more, or even all, of the method steps in one or more of the methods disclosed in the embodiments herein can be performed, supported, or assisted using a computer or computer network. Therefore, typically, any of the method steps involving the provision and / or manipulation of data can be performed using a computer or computer network. Generally, these method steps can include any method steps except those that typically require manual work, such as providing spectrometer equipment, and / or providing an object and / or performing certain aspects of the actual measurement.

[0085] In another aspect of the invention, a computer program is disclosed that includes instructions, when executed by a spectrometer device according to the invention (e.g., according to any of the embodiments disclosed above and / or according to any of the embodiments further detailed below), causing the spectrometer device to perform at least steps b) to d) of the method according to the invention (e.g., according to any of the embodiments disclosed above and / or according to any of the embodiments further detailed below).

[0086] In another aspect of the invention, a computer-readable storage medium is disclosed, specifically a non-transitory computer-readable medium comprising instructions that, when executed by a spectrometer device according to the invention (e.g., according to any of the embodiments disclosed above and / or according to any of the embodiments further detailed below), cause the spectrometer device to perform at least steps b) to d) of the method according to the invention (e.g., according to any of the embodiments disclosed above and / or according to any of the embodiments further detailed below).

[0087] As used herein, the term "computer-readable storage medium" can specifically refer to a non-transitory data storage device, such as a hardware storage medium on which computer-executable instructions are stored. Computer-readable storage media can specifically be or can include storage media such as random access memory (RAM) and / or read-only memory (ROM).

[0088] In one or more of the above embodiments and / or in one or more of the embodiments further described in detail below, the spectrometer apparatus and method according to the invention offer numerous advantages over known apparatuses and methods of similar types. The spectrometer apparatus including a broadband detector provides the possibility of obtaining spectroscopic information about an object using both primary and secondary light, specifically by selecting and / or extending the spectral emission range through the use of a pump LED having a shorter emission wavelength and a luminescent material having an emission spectrum at a longer wavelength. For a particular application, the emission spectra of the pump LED and the luminescent material may not be used complementaryly, and therefore, the spectral portions of the primary and secondary light can be used to address different applications.

[0089] In the field of consumer-grade spectroscopy, the spatial distribution of an object's depth and / or volume may be known for many use cases. For example, the spatial distribution of objects including painted wood (e.g., with a coating on its surface), skin (e.g., different skin layers), or laminated materials may be known. Therefore, the spectral ranges of primary and secondary light with different penetration depths within the object can be used to obtain both spectroscopic information about the object, specifically volumetric spectroscopic information about the object, and surface spectroscopic information about the object. Specifically, it may be advantageous to simultaneously study different parts of the object, such as the object's surface and volume, by using both primary and secondary light, specifically by using different portions of the total emission spectrum produced by pumping LEDs and luminescent materials, using both primary and secondary light. Combining spectral measurements using primary and secondary light can provide better context for applications where the relationship between the measured data and the characteristic under investigation may not be very strong and / or where this relationship varies greatly for different objects. As an example, this may be applicable to health applications, where conditions vary greatly for different people and / or even throughout the day.

[0090] To detect radiation in two wavelength ranges, the spectrometer apparatus includes a broadband detector, specifically implemented by two or more individual detector elements or a single broadband detector, sensitive to both wavelength ranges of primary and secondary light, specifically sensitive to both the pump wavelength range of the LED and the conversion wavelength range of the luminescent material. When using a single broadband detector to detect both types of radiation, pulse duration modulation of the light source allows for differentiation between the primary and secondary detector signals. Furthermore, the spectrometer apparatus and method according to the invention allow for the simultaneous study of two different use cases that can be addressed using primary and secondary light (specifically, the radiation pumping the LED and the radiation from the luminescent material).

[0091] As used herein, the terms “have,” “include,” or “contain,” or any of their grammatical variations, are used in a non-exclusive manner. Thus, these terms can refer either to a situation where no other features exist in the entity described in the context besides those introduced by these terms, or to a situation where one or more other features exist. For example, the statements “A has B,” “A includes B,” and “A contains B” can refer either to a situation where no other elements exist in A besides B (i.e., A consists solely of B), or to a situation where entity A contains one or more other elements besides B (such as element C, elements C and D, or even other elements).

[0092] Furthermore, it should be noted that the terms "at least one," "one or more," or similar expressions indicating a feature or element may appear once or more, but are typically used only once when describing the corresponding feature or element. In most cases, the expressions "at least one" or "one or more" are not repeated when referring to the corresponding feature or element, but in fact, the corresponding feature or element may appear once or more.

[0093] Furthermore, as used herein, the terms “preferredly,” “more preferably,” “particularly,” “more particularly,” “specifically,” “more specifically,” or similar terms are used in combination with optional features without limiting the possibility of alternatives. Therefore, the features introduced by these terms are optional features and are not intended to limit the scope of the claims in any way. As those skilled in the art will recognize, the invention can be practiced by using alternative features. Similarly, features introduced by phrases such as “in embodiments of the invention” are intended to be optional features and do not limit any alternative embodiments of the invention, the scope of the invention, or the possibility of combining features introduced in this way with other optional or non-optional features of the invention.

[0094] In summary, and without excluding other possible embodiments, the following embodiments are conceivable:

[0095] Example 1: A spectrometer device for obtaining spectroscopic information about at least one object, the spectrometer device comprising:

[0096] i. At least one light source for generating illumination light for illuminating the object, the light source comprising at least one light-emitting diode and at least one light-emitting material for converting primary light generated by the light-emitting diode into secondary light, wherein the illumination light comprises at least partially the primary light and the secondary light;

[0097] ii. At least one broadband detector for detecting detection light from the object in a spectral range that at least partially includes the spectral ranges of the primary light and the secondary light, wherein the broadband detector is configured to generate at least one primary detector signal when the detection light is detected in the spectral range of the primary light, and wherein the broadband detector is further configured to generate at least one secondary detector signal when the detection light is detected in the spectral range of the secondary light; and

[0098] iii. At least one evaluation unit, the at least one evaluation unit being used to evaluate at least one of the primary detector signal and the secondary detector signal generated by the broadband detector, and to determine spectroscopic information about the object based on at least one of the primary detector signal and the secondary detector signal.

[0099] Example 2: According to the spectrometer device of the previous embodiment, the evaluation unit is configured to evaluate the primary detector signal generated by the broadband detector and to obtain first applied spectroscopic information about the object from the primary detector signal.

[0100] Example 3: According to the spectrometer device of the previous embodiment, the first applied spectroscopic information about the object includes at least one of volume spectroscopic information about the object and surface spectroscopic information about the object.

[0101] Example 4: A spectrometer device according to any one of the foregoing embodiments, wherein the evaluation unit is configured to evaluate the secondary detector signal generated by the broadband detector and to obtain second applied spectroscopic information about the object from the secondary detector signal.

[0102] Example 5: According to the spectrometer device of the previous embodiment, the second applied spectroscopic information about the object includes at least one of volume spectroscopic information about the object and surface spectroscopic information about the object.

[0103] Example 6: A spectrometer device according to any one of the foregoing embodiments, wherein the broadband detector is configured to detect light from the object in a spectral range of 200 nm to 5 µm, preferably 300 nm to 3 µm, more preferably 400 nm to 2.5 µm.

[0104] Example 7: The spectrometer device according to any one of the foregoing embodiments, wherein the broadband detector includes a plurality of detector elements for detecting detection light within the spectral range of the primary light and the secondary light.

[0105] Example 8: The spectrometer device according to the previous embodiment, wherein each detector element includes at least one photosensitive material selected from PbS, PbSe, InSb, or HgCdTe.

[0106] Example 9: A spectrometer device according to any one of the preceding two examples, wherein each detector element includes a photodiode, particularly a photodiode including at least one of Si, Ge, InGaAs, or epitaxial InGaAs.

[0107] Example 10: The spectrometer device according to any one of the foregoing embodiments, wherein the broadband detector is a single detector, the single detector comprising at least one photosensitive material selected from PbS, PbSe, InSb, or HgCdTe.

[0108] Example 11: The spectrometer device according to any one of the foregoing embodiments, wherein the broadband detector is a single detector, the single detector comprising a photodiode, particularly a photodiode comprising at least one of Si, Ge, InGaAs, or epitaxial InGaAs.

[0109] Example 12: The spectrometer device according to the previous embodiment further includes at least one driving unit for electrically driving the light source, wherein the driving unit is configured to drive the light-emitting diode at at least one driving frequency, wherein the driving frequency exceeds the time constant of the light-emitting material. The reciprocal of.

[0110] Example 13: According to the spectrometer device of the previous embodiment, the evaluation unit is configured to distinguish the primary detector signal from the secondary detector signal by demodulation, for example by using Fourier transform, particularly fast Fourier transform.

[0111] Example 14: The spectrometer device according to any one of the foregoing embodiments, wherein the illumination light includes the portion of the primary light generated by the light-emitting diode that is not converted into the secondary light by the light-emitting material, and the secondary light.

[0112] Example 15: The spectrometer device according to any one of the preceding embodiments, wherein the primary light is at least partially located in the spectral range of 380 nm to 1000 nm, specifically in the spectral range of 420 nm to 940 nm, more specifically in the spectral range of 420 nm to 830 nm, and more specifically in the spectral range of 440 nm to 830 nm.

[0113] Example 16: According to the spectrometer device of the previous embodiment, the primary light that is not converted into secondary light by the luminescent material is at least partially located in the spectral range of 380 nm to 1000 nm, specifically in the spectral range of 420 nm to 940 nm, more specifically in the spectral range of 420 nm to 830 nm, and more specifically in the spectral range of 440 nm to 830 nm.

[0114] Example 17: The spectrometer device according to any one of the preceding embodiments, wherein the secondary light is at least partially located in the spectral range of 1 µm to 5 µm, specifically in the spectral range of 1.5 μm to 3 μm, and more specifically in the spectral range of 1.5 μm to 2.5 μm.

[0115] Example 18: The spectrometer device according to any one of the foregoing embodiments, wherein the light source includes a phosphor light-emitting diode.

[0116] Example 19: A spectrometer device according to any one of the foregoing embodiments, wherein the spectrometer device further includes at least one wavelength selection element, wherein the wavelength selection element is arranged such that the broadband detector generates the at least one primary detector signal when detecting the detection light within the spectral range of the primary light, and generates the at least one secondary detector signal when detecting the detection light within the spectral range of the secondary light.

[0117] Example 20: According to the spectrometer device of the previous embodiment, the wavelength selection element includes at least one of a wavelength selection element disposed in the beam path of the illumination light or a wavelength selection element disposed in the beam path of the detection light.

[0118] Example 21: A spectrometer device according to any one of the preceding two examples, wherein the wavelength selection element is selected from at least one of a tunable wavelength selection element or a wavelength selection element having a fixed transmission spectrum.

[0119] Example 22: According to the spectrometer device of the previous embodiment, the wavelength selection element having a fixed transmission spectrum includes at least one filter element, specifically at least one absorption filter element, and more specifically a bandpass filter element.

[0120] Example 23: A spectrometer device according to any one of the preceding two examples, wherein the tunable wavelength selection element includes at least one tunable interferometer, specifically at least one of a MEMS Fabry-Perot interferometer and a MEMS Michelson interferometer.

[0121] Example 24: A method for obtaining spectroscopic information about at least one object, the method comprising:

[0122] a) Provide at least one spectrometer device according to any one of the foregoing embodiments;

[0123] b) Illuminate the object with illumination light generated by the light source, the light source comprising at least one light-emitting diode and at least one light-emitting material for converting primary light generated by the light-emitting diode into secondary light, wherein the illumination light comprises at least partially the primary light and the secondary light;

[0124] c) Detecting detection light from the object within a spectral range that at least partially includes the spectral range of the primary light and the secondary light by using at least one broadband detector, wherein the broadband detector is configured to generate at least one primary detector signal when the detection light is detected within the spectral range of the primary light, and wherein the broadband detector is configured to generate at least one secondary detector signal when the detection light is detected within the spectral range of the secondary light; and

[0125] d) By using the evaluation unit, at least one of the primary detector signal and the secondary detector signal generated by the broadband detector is evaluated, and spectroscopic information about the object is obtained from at least one of the primary detector signal and the secondary detector signal.

[0126] Example 25: The method according to the previous embodiment, wherein step d) includes evaluating the primary detector signal generated by the broadband detector, and obtaining first applied spectroscopic information about the object from the primary detector signal.

[0127] Example 26: According to the method described in the previous embodiment, the first applied spectroscopic information about the object includes at least one of volume spectroscopic information about the object and surface spectroscopic information about the object.

[0128] Example 27: The method according to any one of the foregoing method embodiments, wherein step d) includes evaluating the secondary detector signal generated by the broadband detector, and obtaining second applied spectroscopic information about the object from the secondary detector signal.

[0129] Example 28: According to the method described in the previous embodiment, the second applied spectroscopic information about the object includes at least one of volume spectroscopic information about the object and surface spectroscopic information about the object.

[0130] Example 29: According to any one of the foregoing method embodiments, the spectrometer device further includes at least one driving unit for electrically driving the light source, wherein the method includes: specifically, in step b), driving the light-emitting diode at at least one driving frequency using the driving unit, wherein the driving frequency is higher than the time constant of the light-emitting material. The reciprocal of.

[0131] Example 30: According to the method described in the previous embodiment, the evaluation in step d) includes distinguishing the primary detector signal from the secondary detector signal by demodulation, such as by using Fourier transform, particularly fast Fourier transform.

[0132] Example 31: The method according to any one of the foregoing method embodiments, wherein the method is at least partially implemented by a computer, specifically at least step d).

[0133] Example 32: A computer program comprising instructions, which, when executed by a spectrometer device according to any of the foregoing embodiments relating to a spectrometer device, cause the spectrometer device to perform at least steps b) to d) of the method according to any of the foregoing embodiments relating to a method.

[0134] Example 33: A computer-readable storage medium, specifically a non-transitory computer-readable medium, includes instructions that, when executed by a spectrometer device according to any of the foregoing embodiments relating to a spectrometer device, cause the spectrometer device to perform at least steps b) to d) of the method according to any of the foregoing embodiments relating to a method. Attached Figure Description

[0135] Further optional features and embodiments will be disclosed in more detail, preferably in conjunction with the dependent claims, in the following embodiments. As those skilled in the art will recognize, the corresponding optional features can be implemented independently and in any feasible combination. The scope of the invention is not limited to the preferred embodiments. Embodiments are schematically depicted in the accompanying drawings. The same reference numerals in these drawings denote the same or functionally equivalent elements.

[0136] In the attached diagram:

[0137] Figure 1 A schematic overview of an embodiment of the spectrometer apparatus is shown;

[0138] Figure 2 A schematic cross-sectional view of an embodiment of the light source is shown;

[0139] Figure 3 A flowchart illustrating an embodiment of a method for obtaining spectroscopic information about at least one object is shown;

[0140] Figure 4 A graph showing the spectral response of the broadband detector is presented;

[0141] Figure 5 A graph showing absorbance as a function of wavelength is shown; and

[0142] Figure 6 A diagram showing pulse duration modulation is presented. Detailed Implementation

[0143] exist Figure 1 The diagram illustrates a schematic overview of a spectrometer apparatus 110 for obtaining spectroscopic information about at least one object 112. The spectrometer apparatus 110 may include, for example... Figure 1 The following section will refer to the various components shown. Figure 1 The possible components of the spectrometer device 110 and their interactions are described. The spectrometer device 110 includes at least one light source 114 for generating illumination light 116 for illuminating an object 112. The light source 114 may be at least one of a tunable light source, a light source having at least one fixed emission wavelength, and a broadband light source. Specifically, the light source 114 may be or may include at least one electric light source. The light source 114 includes at least one light-emitting diode 118 and at least one light-emitting material 120 for converting the primary light generated by the light-emitting diode 118 into secondary light. As an example, the light-emitting diode 118 may include one or more of the following: a spontaneous emission-based light-emitting diode (LED), a superluminescent light-emitting diode (sLED), and a laser diode (LLED).

[0144] LED 118 may specifically include at least two semiconductor material layers 121, wherein light can be generated at at least one interface between the at least two semiconductor material layers 121, specifically due to the recombination of positive and negative charges. The at least two semiconductor material layers 121 may have different electrical properties; for example, at least one of these layers may be an n-doped semiconductor material 121, and at least one of these layers may be a p-doped semiconductor material 121. Therefore, by way of example, LED 118 may include at least one pn junction and / or at least one pin structure. However, it should be noted that other device structures are also feasible.

[0145] The light-emitting diode 118 can generate primary light, which may also be referred to as "pump light". The primary light can then be converted into "secondary light", for example, by using a light conversion (e.g., by one or more light-emitting materials 120, such as phosphors)). Thus, at least one light-emitting material 120 can form at least one converter (also called a light converter) that converts the primary light into secondary light with different spectral characteristics compared to the primary light. Specifically, the spectral width of the secondary light may be greater than that of the primary light, and / or the emission center of the secondary light may be shifted (specifically, redshifted). Specifically, at least one light-emitting material 120 may be absorptive in the ultraviolet and / or blue spectral range, and emissive in the near-infrared and / or infrared spectral range. The illumination light 116 at least partially comprises the primary light and the secondary light. Specifically, the illumination light 116 may include those portions of the primary light generated by the light-emitting diode 118 that are not converted into secondary light by the light-emitting material 120 (e.g., due to the low conversion efficiency of the light-emitting material 120), as well as the secondary light.

[0146] like Figure 1 As indicated, the light source 114 may specifically include a phosphor light-emitting diode 122, also referred to as a phosphor LED 122. The phosphor LED 122 may be a combination of at least one light-emitting diode 118 configured to generate primary light or pump light and at least one light-emitting material 120 (also referred to as a "phosphor") configured to convert the primary light generated by the light-emitting diode 118. The phosphor LED 122 may form an encapsulated LED light source including an LED die 124 (e.g., a blue LED emitting blue pump light) and a phosphor, for example, which is wholly or partially coated on the LED 118 and, by way of example, configured to convert primary light or blue light into light with different spectral characteristics (specifically, into near-infrared light). Figure 2 A more detailed view of the light source 114, which is implemented as a phosphor LED 122, is shown.

[0147] Typically, the light source 114 can be implemented in various ways. Therefore, the light source 114 can, for example, be part of the spectrometer device 110 within the housing 126 of the spectrometer device 110, such as... Figure 1 As shown. However, alternatively or additionally, at least one light source 114 may also be arranged outside the housing 126, for example as a separate light source 114 (not shown). The light source 114 may be arranged separately from the object 112 and illuminate the object 112 from a distance, such as Figure 1 As indicated.

[0148] For example, illumination light 116 generated by light source 114 can propagate from light source 114 to object 112. Figure 1In the diagram, the illumination light 116 generated by the light source 114 and propagating to the object 112 is indicated by arrows. Specifically, the object 112 may include at least one sample, which can be fully or partially analyzed by spectroscopic methods.

[0149] As from Figure 1 As is evident, the spectrometer device 110 further includes at least one broadband detector 128 configured to detect detection light 130 from the object 112 within a spectral range that at least partially includes primary and secondary light. Light propagating from the light source 114 to the object 112 may be referred to as illumination light 116, while light propagating from the object 112 to the broadband detector 128 may be referred to as detection light 130. Figure 1 In the diagram, detection light 130 is indicated by an arrow. Detection light 130 may include at least one of the following: illumination light 116 reflected by object 112, illumination light 116 scattered by object 112, illumination light 116 transmitted by object 112, and luminous light generated by object 112 (e.g., phosphorescence or fluorescence generated by object 112 after optical, electrical, or acoustic excitation by illumination light 116). Therefore, detection light 130 can be generated directly or indirectly by irradiating object 112 with illumination light 116.

[0150] A broadband detector 128 is configured to generate at least one primary detector signal when detection light 130 within the spectral range of primary light is detected. The broadband detector 128 is further configured to generate at least one secondary detector signal when detection light 130 within the spectral range of secondary light is detected. For example, the broadband detector 128 may include a plurality of detector elements 132, such as a photosensitive element array, for detecting detection light 130 within the spectral ranges of both primary and secondary light. The broadband detector 128 may include a pixelated broadband detector comprising a plurality of optically sensitive pixels or elements, as described in detail above. For example, the broadband detector 128 may include at least one first detector element 131 for detecting detection light 130 within the spectral range of primary light, and at least one second detector element 133 for detecting detection light 130 within the spectral range of secondary light. Specifically, the first detector element 131 may be configured to generate a primary detector signal when detection light 130 within the spectral range of primary light is detected. The second detector element 133 can be configured to generate a secondary detector signal when detection light 130 is detected within the spectral range of the secondary light. Each detector element 131, 133 may include at least one photosensitive material selected from PbS, PbSe, InSb, or HgCdTe. Alternatively, the broadband detector 128 may be a single detector 134 comprising at least one photosensitive material selected from PbS, PbSe, InSb, or HgCdTe. As another alternative, the broadband detector 128 may be a single detector 134 having a photodiode (especially a photodiode comprising at least one material selected from Si, Ge, InGaAs, or epitaxial InGaAs). Figure 1 In the accompanying drawings, reference numerals 132 and 134 together are used to indicate the arrangement of a plurality of detector elements 132 and a single detector 134 in the spectrometer device 110, although in one embodiment the spectrometer device 110 may include a plurality of detector elements 132, while in an alternative embodiment it may include a single detector 134.

[0151] The broadband detector 128 can be adapted to generate an electrical signal based on the intensity of the incident light, wherein the electrical signal can be specifically provided to the evaluation unit 136 of the spectrometer device 110, as will be further described in detail below.

[0152] The spectrometer device 110 includes at least one evaluation unit 136 for evaluating at least one of a primary detector signal and a secondary detector signal generated by a broadband detector 128, and for determining spectroscopic information about the object 112 based on at least one of the primary and secondary detector signals. The broadband detector 128 can provide detector signals directly or indirectly to the evaluation unit 136. Therefore, the broadband detector 128 and the evaluation unit 136 can be directly or indirectly connected, such as... Figure 1 As indicated by the arrow in the diagram. The detector signal can be used as the "raw" detector signal and / or can be processed or preprocessed (e.g., by filtering) before further use. Therefore, the broadband detector 128 may include at least one processing device and / or at least one preprocessing device, such as at least one of an amplifier, an analog-to-digital converter, an electrical filter, and a Fourier transform.

[0153] like Figure 1 As shown, the spectrometer device 110 may further include at least one driving unit 138 for electrically driving the light source 114. The driving unit 138 may be configured to supply current to the LED 118, specifically for controlling the current through the LED 118. As an example, the driving unit 138 may be configured to adapt and measure the voltage supplied to the LED 118, which is required to achieve a specific current through the LED 118. The driving unit 138 may specifically include one or more of the following: a current source 140, a voltage source, a current measuring device (e.g., an ammeter), a voltage measuring device 142 (e.g., a voltmeter), and a power measuring device. Specifically, the driving unit 138 may include at least one current source 140 for supplying at least one predetermined current to the LED 118, wherein the current source 140 may be specifically configured to adjust or control the voltage applied to the LED 118 to generate the predetermined current. As an example, the driving unit 138 may include one or more electrical components (e.g., integrated circuits) for driving the light source 114. The drive unit 138 can be fully or partially integrated into the light source 114, or it can be separated from the light source 114; the latter configuration is... Figure 1 It is displayed in the middle.

[0154] Where the broadband detector 128 can be a single detector 134, the driving unit 138 may specifically be included by the spectrometer device 110. However, the spectrometer device 110 may also include a driving unit 138 for other embodiments of the broadband detector 128. The driving unit 138 may be configured to drive the light-emitting diode 118 at at least one driving frequency. The driving frequency may specifically exceed the attenuation constant of the light-emitting material 120. The reciprocal of the first and second detector signals. Furthermore, the evaluation unit 136 can be configured to distinguish the primary detector signal from the secondary detector signal by demodulation (e.g., by using Fourier transform, particularly fast Fourier transform). Therefore, the spectrometer device 110 can be configured to modulate the pulse duration of the light source 114 using the drive unit 138.

[0155] As outlined above, and as... Figure 1 As shown, the spectrometer device 110 includes at least one evaluation unit 136, which is used to evaluate at least one of a primary detector signal and a secondary detector signal generated by the broadband detector 128, and to obtain spectroscopic information about the object 112 from the primary detector signal and the secondary detector signal. Specifically, the evaluation unit 136 may be configured to evaluate the primary detector signal generated by the broadband detector 128 and to obtain first applied spectroscopic information about the object 112 from the primary detector signal. The first applied spectroscopic information about the object 112 may include at least one of volumetric spectroscopic information about the object 112 and surface spectroscopic information about the object 112. Additionally or alternatively, the evaluation unit 136 may be configured to evaluate the secondary detector signal generated by the broadband detector 128 and to obtain second applied spectroscopic information about the object 112 from the secondary detector signal. The second applied spectroscopic information about the object 112 may include at least one of volumetric spectroscopic information about the object 112 and surface spectroscopic information about the object 112.

[0156] Evaluation unit 136 may be or may include one or more integrated circuits (such as one or more application-specific integrated circuits (ASICs)) and / or one or more data processing devices 144 (such as one or more of a computer, digital signal processor (DSP), field-programmable gate array (FPGA), etc.), preferably one or more microcomputers and / or microcontrollers. Additional components may be included, such as one or more preprocessing devices 146 and / or data acquisition devices, such as one or more devices for receiving and / or preprocessing detector signals, such as one or more AD converters and / or one or more filters. Further, evaluation unit 136 may include one or more data storage devices 148, such as... Figure 1 As shown. Furthermore, the evaluation unit 136 may include one or more interfaces, such as one or more wireless interfaces and / or one or more wired interfaces.

[0157] The spectrometer device 110 may further include one or more optical components 150, such as at least one mirror, at least one lens, at least one aperture, and at least one wavelength selection element 152. The wavelength selection element 152 may be arranged such that the broadband detector 128 generates at least one primary detector signal when detecting detection light 130 within the spectral range of primary light, and generates at least one secondary detector signal when detecting detection light 130 within the spectral range of secondary light. Figure 1 As shown, wavelength selection by at least one wavelength selection element 152 can be performed in at least one beam path of the illumination light 116, thereby selecting and / or modifying the illumination wavelength of the object 112, and / or in the detection beam path of the detection light 130, thereby selecting and / or modifying the detection wavelength, for example, generally for the broadband detector 128 and / or for each detector element 131, 133. The wavelength selection element 152 may include at least one of wavelength selection elements 152 disposed in the beam path of the illumination light 116 or wavelength selection elements 152 disposed in the beam path of the detection light 130. Specifically, the wavelength selection element 152 may be selected from at least one of tunable wavelength selection elements or wavelength selection elements having a fixed transmission spectrum.

[0158] For example, wavelength selection element 152 can be arranged in the detection beam path of detection light 130. Wavelength selection element 152 can be configured to direct the detection light 130 within the spectral range of the primary light to a first detector element 131 included in the broadband detector 128, such that the broadband detector 128 detects the detection light 130 within the spectral range of the primary light and thus generates a primary detector signal. Wavelength selection element 152 can be further configured to direct the detection light 130 within the spectral range of the secondary light to a second detector element 133 included in the broadband detector 128, such that the broadband detector 128 detects the detection light 130 within the spectral range of the secondary light and thus generates a secondary detector signal. Alternatively, broadband detector 128 can be a single detector 134 as outlined above, and wavelength selection element 152 can be a tunable wavelength selection element, allowing adjustment of the spectral range to be detected by broadband detector 128.

[0159] like Figure 1The spectrometer device 110, schematically represented, is configured to acquire spectroscopic information about at least one object 112. Specifically, the spectrometer device 110 may be configured to acquire, for example, information about at least one object 112 and / or radiation emitted by the object 112, characterizing at least one optical property of the object 112, and more specifically, characterizing, for example, at least one information about qualitatively and / or quantitatively representing at least one of transmission, absorption, reflection, and emission of the object 112. As an example, at least one spectral information item may include at least one intensity information, such as information about the intensity of at least one type of light transmitted, absorbed, reflected, or emitted by the object 112, the intensity being, for example, a function of wavelength or a subrange of wavelength within one or more wavelength ranges (e.g., within a wavelength range). Therefore, the spectrometer device 110 may be configured to acquire at least one spectrum or at least a portion of a spectrum of detection light 130 propagating from the object 112 to the broadband detector 128. The spectrum may be given in radiometric units describing spectral flux, for example, in watts per nanometer (W / nm), or in other units, for example, as a function of the wavelength of the detection light 130. Therefore, a spectrum can describe, for example, the optical power of light within a specific wavelength band in the NIR spectral range. A spectrum can include one or more optical variables that vary with wavelength, such as power spectral density, electrical signals obtained through optical measurements, etc. Specifically, a spectrum can include the spectral ranges of primary and secondary light. The spectrometer device 110 can specifically be a portable spectrometer device (e.g., as part of a mobile device), or can be attached to a mobile device such as a laptop computer, tablet computer, cellular phone (e.g., smartphone), smartwatch, and / or wearable computer. Figure 1 (Not shown in the image).

[0160] exist Figure 2 A schematic cross-sectional view of light source 114 is shown. At least one light source 114 of the spectrometer device 110 can be configured to generate or provide electromagnetic radiation in one or more of the infrared, visible, and ultraviolet spectral ranges. Because many material properties or chemical compositional properties of many objects 112 are available from the near-infrared spectral range, the light used for the typical purposes of the present invention is light in the infrared (IR) spectral range, more preferably in the near-infrared (NIR) and / or mid-infrared spectral range (MidIR), especially light with wavelengths of 1 to 5 µm, preferably 1 to 3 µm. Light source 114 includes at least one light-emitting diode 118 and at least one light-emitting material 120 for light conversion of the primary light generated by the light-emitting diode 118. As described above, the LED 118 and the light-emitting material 120 together can form a phosphor LED 122.

[0161] like Figure 2As shown, the phosphor LED 122 may include one or more functional components. Specifically, the phosphor LED 122 may include one or more substrates 154, specifically one or more electrically insulating substrates 154. More particularly, the phosphor LED 122 may include one or more ceramic substrates 156, such as... Figure 2 As shown. The substrate 154 can be configured to hold at least one LED die 124 and at least one light-emitting material 120. Further, at least one substrate 154 can hold or include one or more electrical connection components, such as... Figure 2 The diagram shows one or more contact pads 158 and / or one or more electrical leads, such as one or more metal contacts and / or one or more metal leads. The substrate 154 can be configured to serve as a heat sink. For example, during the conversion process, heat can be generated in the LED die 124 (e.g., due to the limited conversion of electrical energy to photonic energy) and in the light-emitting material 120. This heat can be dissipated in the substrate 154, for example, in a ceramic substrate.

[0162] like Figure 2 As shown, the phosphor LED 122 may include a light-emitting diode 118. The light-emitting diode 118 can be configured for use as... Figure 2 The at least one LED chip and / or at least one LED die 124 shown converts current into primary light, such as blue primary light. Specifically, a pn junction diode can be used. As an example, one or more LEDs 118 selected from the group consisting of indium gallium nitride (InGaN)-based LEDs 118, GaN-based LEDs 118, InGaN / GaN alloy-based LEDs 118, or combinations thereof, and / or other LEDs 118 can be used. Additionally or alternatively, quantum well LEDs 118, such as one or more InGaN-based quantum well LEDs 118, can also be used. Additionally or alternatively, superradiative LEDs (sLEDs) and / or quantum cascade lasers can be used. Figure 2 As is further apparent, the phosphor LED may include at least one luminescent material 120 configured to perform light conversion on the primary light generated by the light-emitting diode 118. Various types of conversion and / or light emission are known and may be used in the context of this invention. Specifically, the luminescent material 120 may include at least one of the following: cerium-doped YAG (YAG:Ce3+ or Y3Al5O12:Ce3+); rare-earth-doped Sialon; copper-aluminum co-doped zinc sulfide (ZnS:Cu,Al).

[0163] Specifically, the light-emitting material 120 can be formed into at least one layer. Various alternatives for positioning the light-emitting material 120 relative to the light-emitting diode 118 are generally feasible, and these alternatives can be used alone or in combination. Firstly, the light-emitting material 120 (e.g., at least one layer of the light-emitting material 120, such as a phosphor) can be directly positioned on the light-emitting diode 118, for example, without material between the LED 118 and the light-emitting material 120, or with one or more transparent materials between them, such as one or more transparent materials (specifically, transparent to primary light) between the LED and the light-emitting material 120. Therefore, as an example, a coating of the light-emitting material 120 can be placed directly or indirectly on the LED 118 (not shown). Additionally or alternatively, as an example, the light-emitting material 120 can form at least one conversion element 160, such as at least one conversion disk, which can also be referred to as a conversion sheet. The conversion element 160 can be placed on top of the LED 118, for example, as shown in the image. Figure 2 As shown, the transducer 160 is attached to the LED 118 with an adhesive. Additionally or alternatively, the light-emitting material 120 can also be placed remotely, such that primary light from the LED 118 must pass through an intermediate optical path before reaching the light-emitting material 120 (not shown). Again, by way of example, the remotely placed light-emitting material 120 can be formed as a solid or transducer 160, such as a disk or transducer disk. One or more optical elements, such as lenses, prisms, gratings, mirrors, apertures, or combinations thereof, can be placed in the intermediate optical path. Therefore, specifically, an optical system with imaging characteristics can be placed in the intermediate optical path, between the LED 118 and the light-emitting material 120. Thus, by way of example, primary light can be focused or converged onto the transducer 160.

[0164] In the light source 114 (specifically, phosphor LED 122), at least one light-emitting material 120 can be positioned relative to the light-emitting diode 118 such that heat transfer can occur from the light-emitting diode 118 to the light-emitting material 120. More specifically, the light-emitting material 120 can be positioned such that heat transfer can occur via one or both of thermal radiation and thermal conduction (more preferably via thermal conduction). Thus, as an example, the light-emitting material 120 can be in thermal and / or physical contact with the light-emitting diode 118, such as... Figure 2 As shown. Thus, typically, the temperature of the light-emitting material 120 and the temperature of the light-emitting diode 118 can be coupled.

[0165] like Figure 2As shown, the light source 114 (specifically, phosphor LED 122) may include additional components, such as at least one side coating 162 covering at least one side (e.g., top surface, bottom surface, and / or one or more lateral sides) of at least one of the following: substrate 154, contact pads 158, light-emitting diode 118, and light-emitting material 120. Specifically, the side coating 162 may cover voids and / or gaps that may exist within the layered arrangement of the light source 114, such as... Figure 2 As shown. Other components of the light source 114 (specifically...) Figure 2 (Components not shown) are feasible. Typically, the light source 114 (especially the phosphor LED 122) can be encapsulated in a housing ( Figure 2 (Not shown in the image) or may be unencapsulated. Therefore, the LED 118 and at least one light-emitting material 120 for light conversion of the primary light generated by the LED 118 can be specifically housed in a common housing. However, alternatively, the LED 118 may also be a housing-less or bare LED 118, such as... Figure 2 What is shown.

[0166] Figure 3 A flowchart illustrating an exemplary embodiment of a method for obtaining spectroscopic information about at least one object 112 is shown. The method includes the following steps, which can be performed in a given order. However, different orders are also possible. In particular, one, more than one, or even all method steps may be performed once or repeatedly. Further, these method steps may be performed sequentially, or alternatively, one or more method steps may be performed in a timely overlapping manner or even in a parallel and / or combined manner. The method may further include additional method steps not listed.

[0167] The method includes:

[0168] a) (indicated by reference numeral 164) provides at least one invention according to (e.g., according to) Figure 1 Spectrometer apparatus 110 (an exemplary embodiment and / or any other embodiment disclosed herein);

[0169] b) (represented by reference numeral 166) Illuminate object 112 with illumination light 116 generated by light source 114, light source 114 including at least one light-emitting diode 118 and at least one light-emitting material 120 for converting primary light generated by light-emitting diode 118 into secondary light, wherein illumination light 116 includes at least part of primary light and secondary light.

[0170] c) (indicated by reference numeral 168) Detection of detection light 130 from object 112 in a spectral range that at least partially includes primary and secondary light by using at least one broadband detector 128, wherein the broadband detector 128 is configured to generate at least one primary detector signal when detection light 130 in the spectral range of primary light is detected, and wherein the broadband detector 128 is configured to generate at least one secondary detector signal when detection light 130 in the spectral range of secondary light is detected; and

[0171] d) (represented by reference numeral 170) At least one of the primary detector signal and the secondary detector signal generated by the broadband detector 128 is evaluated by using the evaluation unit 136, and spectroscopic information about the object 112 is obtained from the primary detector signal and the secondary detector signal.

[0172] Step d) may include evaluating the primary detector signal generated by the broadband detector 128, and obtaining first applied spectroscopic information about the object 112 from the primary detector signal. Specifically, the first applied spectroscopic information about the object 112 may include at least one of volumetric spectroscopic information about the object 112 and surface spectroscopic information about the object 112. Additionally, step d) may include evaluating the secondary detector signal generated by the broadband detector 128, and obtaining second applied spectroscopic information about the object 112 from the secondary detector signal. The second applied spectroscopic information about the object 112 may include at least one of volumetric spectroscopic information about the object 112 and surface spectroscopic information about the object 112.

[0173] As outlined above, the spectrometer device 110 may further include at least one driving unit 138 for electrically driving the light source 114. The method may include, specifically, in step b), driving the light-emitting diode 118 at at least one driving frequency using the driving unit 138. The driving frequency may be higher than the time constant of the luminescent material 120. The reciprocal of . Specifically, this operating mode of light source 114 can also be referred to as pulse duration modulation. The evaluation in step d) may include distinguishing the primary detector signal from the secondary detector signal by demodulation (e.g., by using Fourier transform, particularly fast Fourier transform).

[0174] exist Figure 4 The diagram shows a graph of the spectral response of an exemplary broadband detector 128. Specifically, Figure 4 The graph illustrates the spectral response, which includes the normalized signal intensity 172 (in arbitrary units) as a function of wavelength 174. (As shown in...) Figure 4As can be seen, the broadband detector 128 can be configured to detect the detection light 130 from the object 112 in the spectral range of 1000 nm to 3000 nm.

[0175] Figure 5 A graph showing absorbance 176 as a function of wavelength 174 is shown. Specifically, in Figure 5 In this figure, the absorbance of water (represented by reference numeral 178), the absorbance of hemoglobin (represented by reference numeral 180), the absorbance of oxidized hemoglobin (represented by reference numeral 182), and the absorbance of melanin (represented by reference numeral 184) are shown as varying with wavelength 174. In this example, the object 112 to be analyzed by the spectrometer device 110 may include the user's skin.

[0176] As in Figure 5 As can be seen, object 112 can be water, which exhibits strong absorption in the NIR spectral range (e.g., in the spectral range of 1300 nm and higher). Therefore, by positioning the secondary light within this spectral range, surface spectroscopic information about object 112 can be obtained by evaluating the secondary detector signal, where, specifically, volumetric spectroscopic information may not be available in this wavelength range. Furthermore, the penetration depth of primary light located in a spectral range including wavelengths of 900 nm or smaller can be greater than that of secondary light. Therefore, in this example, volumetric spectroscopic information can be obtained by evaluating the primary detector signal. Volumetric spectroscopic information can provide information about other effects, such as the effect on melanin concentration or skin color in the example analyzing the skin layer.

[0177] Furthermore, in the example of analyzing user skin, the evaluation unit 136 can be specifically configured to evaluate the primary detector signal generated by the broadband detector 128 and to obtain volumetric spectroscopic information about the object 112. Furthermore, the evaluation unit 136 can be configured to evaluate the secondary detector signal generated by the broadband detector 128 and to obtain surface spectroscopic information about the object 112.

[0178] Figure 6 A diagram of pulse duration modulation is shown. Specifically, in Figure 6 The figure shows, in the time domain, the driving pulse applied to the light-emitting diode 118 (denoted by reference numeral 186) and the resulting pulse of secondary light in the time domain (denoted by reference numeral 188). Figure 6 As can be seen, the pulse train 190 can be specifically applied to the light-emitting diode 118 using the driving unit 138, and the pulse train includes a time constant exceeding that of the light-emitting material 120. The reciprocal of the driving frequency. Since the pump LED 118 can be driven faster than the light-emitting material 120, the pulse of the secondary light may not be able to keep up with the fast driving of the LED 118, and therefore, the pulse form applied to the pump LED 118 can be used so that the frequency domain information obtained from the fast Fourier transform can be provided with spectroscopic information simultaneously from the primary detector signal and the second detector signal using a single detector 134.

[0179] List of reference numerals

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Claims

1. A spectrometer apparatus (110) for obtaining spectroscopic information about at least one object (112), the spectrometer apparatus (110) comprising: i. At least one light source (114) for generating illumination light (116) for illuminating the object (112), the light source (114) comprising at least one light-emitting diode (118) and at least one light-emitting material (120) for converting primary light generated by the light-emitting diode (118) into secondary light, wherein the illumination light (116) comprises at least partially the primary light and the secondary light; ii. At least one broadband detector (128) for detecting detection light (130) from the object (112) in a spectral range that at least partially includes the spectral range of the primary light and the secondary light, wherein the broadband detector (128) is configured to generate at least one primary detector signal when the detection light (130) in the spectral range of the primary light is detected, and wherein the broadband detector (128) is further configured to generate at least one secondary detector signal when the detection light (130) in the spectral range of the secondary light is detected; and iii. At least one evaluation unit (136) configured to evaluate at least one of the primary detector signal and the secondary detector signal generated by the broadband detector (128), and to determine spectroscopic information about the object (112) based on at least one of the primary detector signal and the secondary detector signal, wherein the evaluation unit (136) is configured to... - Evaluate the primary detector signal generated by the broadband detector (128) and use it to obtain first applied spectroscopic information about the object (112) from the primary detector signal; - Evaluate the secondary detector signal generated by the broadband detector (128) and obtain second applied spectroscopic information about the object (112) from the secondary detector signal.

2. The spectrometer apparatus (110) according to the preceding claim, wherein, The broadband detector (128) is configured to detect detection light (130) from the object (112) in the spectral range of 200 nm to 5 µm, preferably 300 nm to 3 µm, more preferably 400 nm to 2.5 µm.

3. The spectrometer apparatus (110) according to any one of the preceding claims, wherein, The broadband detector (128) - Includes a plurality of detector elements (132) for detecting detection light (130) within the spectral range of the primary light and the secondary light, each of the detector elements (132) including a photosensitive material or a photodiode; or - is a single detector (134), which includes the photosensitive material or the photodiode.

4. The spectrometer device (110) according to any one of the preceding claims further includes at least one driving unit (138) for electrically driving the light source (114), wherein, The driving unit (138) is configured to drive the light-emitting diode (118) at at least one driving frequency, wherein the driving frequency exceeds the time constant of the light-emitting material (120). The reciprocal of.

5. The spectrometer apparatus (110) according to any one of the preceding claims, wherein, The evaluation unit (136) is configured to distinguish the primary detector signal from the secondary detector signal by demodulation, for example by using Fourier transform, particularly fast Fourier transform.

6. The spectrometer apparatus (110) according to any one of the preceding claims, wherein, The illumination light (116) includes the portion of the primary light generated by the light-emitting diode (118) that is not converted into the secondary light by the light-emitting material (120), as well as the secondary light.

7. The spectrometer apparatus (110) according to any one of the preceding claims, wherein, The primary light is at least partially located in the spectral range of 380 nm to 1000 nm, and the secondary light is at least partially located in the spectral range of 1 µm to 5 µm.

8. The spectrometer apparatus (110) according to any one of the preceding claims, wherein, The light source (114) includes a phosphor light-emitting diode (122).

9. The spectrometer apparatus (110) according to any one of the preceding claims, wherein, The spectrometer device (110) further includes at least one wavelength selection element (152), wherein the wavelength selection element (152) is arranged such that the broadband detector (128) generates the at least one primary detector signal when the detection light (130) is detected in the spectral range of the primary light, and generates the at least one secondary detector signal when the detection light (130) is detected in the spectral range of the secondary light.

10. A method for obtaining spectroscopic information about at least one object (112), the method comprising: a) Provide at least one spectrometer device (110) according to any one of the preceding claims; b) Illuminate the object (112) with illumination light (116) generated by the light source (114), the light source (114) including at least one light-emitting diode (118) and at least one light-emitting material (120) for converting primary light generated by the light-emitting diode (118) into secondary light, wherein the illumination light (116) includes at least part of the primary light and the secondary light; c) Detecting detection light (130) from the object (112) in a spectral range that at least partially includes the spectral range of the primary light and the secondary light by using at least one broadband detector (128), wherein the broadband detector (128) is configured to generate at least one primary detector signal when the detection light (130) in the spectral range of the primary light is detected, and wherein the broadband detector (128) is configured to generate at least one secondary detector signal when the detection light (130) in the spectral range of the secondary light is detected; and d) By using the evaluation unit (136), at least one of the primary detector signal and the secondary detector signal generated by the broadband detector (128) is evaluated, and spectroscopic information about the object (112) is obtained from at least one of the primary detector signal and the secondary detector signal. Step d) includes - Evaluate the primary detector signal generated by the broadband detector (128), and obtain first applied spectroscopic information about the object (112) from the primary detector signal; - Evaluate the secondary detector signal generated by the broadband detector (128), and obtain second applied spectroscopic information about the object (112) from the secondary detector signal.

11. The method according to the preceding method claim, wherein the spectrometer device (110) further comprises at least one driving unit (138) for electrically driving the light source (114), wherein, The method includes, specifically, in step b), driving the light-emitting diode (118) at at least one driving frequency using the driving unit (138), wherein the driving frequency is higher than the time constant of the light-emitting material (120). The reciprocal of.

12. The method according to any one of the preceding claims, wherein, The evaluation in step d) includes distinguishing the primary detector signal from the secondary detector signal by demodulation, such as by using Fourier transform, especially fast Fourier transform.

13. A computer program comprising instructions, when executed by a spectrometer device (110) according to any one of the preceding claims relating to a spectrometer device (110), causing the spectrometer device (110) to perform at least steps b) to d) of the method according to any one of the preceding method claims.

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