Spectrometer device for acquiring spectral information about at least one object

Abstract

A spectrometer device (110) and a method for acquiring spectral information relating to at least one object (112) are disclosed. The spectrometer device (110) includes: i. At least one light source (114) that generates illumination light (116) for illuminating an object (112), wherein the light source (114) includes 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; ii. At least one broadband detector (128) for detecting detection light (130) in a spectral range that at least partially includes the spectral range of primary light and the spectral range of secondary light, wherein the broadband detector (128) is configured to generate at least one primary detector signal when it detects detection light (130) in the spectral range of primary light, and the broadband detector (128) is configured to generate at least one secondary detector signal when it detects detection light (130) in the spectral range of secondary light; and iii. At least one evaluation unit (136) that evaluates the primary and secondary detector signals generated by the broadband detector (128), determines responsiveness information (137) regarding the broadband detector (128) from either the primary or secondary detector signal, and derives spectral information regarding the object (112) from the other of the primary or secondary detector signal, taking into account the responsiveness information (137) regarding the broadband detector (128).

Description

[Technical Field]

[0001] The present invention relates to a spectrometer apparatus and method for acquiring spectral information relating to at least one object. Furthermore, the present invention relates to a computer program and a computer-readable storage medium for performing the method. Such apparatus and method can generally be used for investigation or surveillance purposes. In particular, they can be used in the infrared (IR) spectral region, especially the near-infrared (NIR) spectral region, and the visible (VIS) spectral region, for example, the spectral region that allows for the imitation of human color vision. However, further applications are possible. [Background technology]

[0002] Spectrometers are known as efficient tools for obtaining information about the spectral properties of an object as it emits, irradiates, reflects, and / or absorbs light. Therefore, spectrometers can assist in sample analysis and other tasks where information about the spectral properties of an object is crucial.

[0003] Typically, in a spectrometer, spectral information is acquired via one or more detectors and one or more wavelength-selective optical elements (e.g., one or more dispersive optical elements, filters such as bandpass filters, prisms, diffraction gratings, interferometers, etc.). Detectors can consist of any type of photosensitive element, such as single or multiple pixel detectors, line detectors, or array detectors with one-dimensional or two-dimensional pixel arrays. Furthermore, a spectrometer may include one or more light sources. Therefore, spectroscopy typically uses tunable light sources such as lasers, and / or broadband light sources such as halogen-filled lamps or high-temperature filaments. However, additionally or alternatively, other light sources such as light-emitting diodes have been proposed for the visible and near-infrared spectral regions.

[0004] As an example, Patent Document 1 (US 2010 / 208261 A1) describes an apparatus for measuring at least one optical property of a sample. The apparatus comprises a variable excitation light source for irradiating the sample with excitation light. The apparatus further comprises a detector for detecting detection light emitted from the sample. The excitation light source includes a light-emitting diode array, at least a portion of which is configured as a monolithic light-emitting diode array. The monolithic light-emitting diode array includes at least three light-emitting diodes, each having a different emission spectrum.

[0005] Patent document 2 (U.S. No. 8,164,050 B2) describes a multi-channel light source assembly for underground spectroscopy, which has individual light sources that generate optical signals at wavelengths across a spectral range. A coupling assembly optically combines the generated signals into a composite signal, and a routing assembly splits the composite signal into a reference channel and a measurement channel. A control circuit electrically connected to the light sources modulates each light source at its own or independent frequency during operation.

[0006] Furthermore, Patent Document 3 (U.S. No. 7,061,618 B2) describes an integrated spectroscopic system, and in some examples, an integrated variable detector using one or more Fabry-Perot variable filters is provided. In other examples, an integrated variable light source is used, which combines one or more diodes, such as superluminescent light-emitting diodes (SLEDs), with a Fabry-Perot variable filter or etalon.

[0007] Furthermore, Patent Document 4 (U.S. Patent No. 5,475,221A) describes an optical device using a light-emitting diode array controlled by a multiplexing method, which replaces conventional broadband light sources in devices such as spectrometers.

[0008] Furthermore, Patent Document 5 (US 2021 / 293620 A1) discloses a spectrometer having the following components: an illumination device for illuminating a spectroscopic measurement area; a detection unit for detecting electromagnetic radiation coming from the spectroscopic measurement area; and a spectroscopic element positioned in the optical path between the illumination device and the detection unit. The illumination device includes: a light-emitting diode designed to emit a first electromagnetic radiation having a first center wavelength and a first spectrum; and a light-emitting element that converts a first component of the first electromagnetic radiation having a first spectrum into a second electromagnetic radiation having a second spectrum. The first center wavelength is 550 nm or 3000 nm, or between 550 nm and 3000 nm. The first spectrum and the second spectrum overlap.

[0009] Furthermore, Patent Document 6 (WO 2018 / 203831 A1) discloses a calibration method for a spectrometer module, including a spectrometer module, which includes performing measurements using the spectrometer module to generate wavelength-to-operating parameter calibration data for the spectrometer module. This method includes performing measurements using a spectrometer module to generate optical crosstalk and dark noise calibration data for the spectrometer module, and performing measurements using the spectrometer module to generate full system response calibration data for the spectrometer module against a known reflectance standard. Furthermore, this method includes storing a calibration record in a memory connected to the spectrometer module, which includes wavelength-to-operating parameter calibration data, optical crosstalk and dark noise calibration data, and full system response calibration data, and applying this calibration record to measurements using the spectrometer module.

[0010] Furthermore, Patent Document 7 (WO 2023 / 052608 A1) discloses a spectroscopic measuring device for measuring light emission provided by at least one object to be measured in at least one classification-based spectroscopic measurement. The spectroscopic measuring device includes: - at least one radiation source configured to emit light radiation at least partially toward an object to be measured, wherein the light radiation is in at least a portion of the spectral range of interest in classification-based spectroscopy; - at least two photodetectors, each photodetector including at least one pixel, each pixel being an active or darkening pixel, the spectroscopic measuring device including at least two active pixels, the spectroscopic measuring device including at least one darkening pixel, each active pixel configured to generate at least one photodetector signal depending on the light incident on the active pixel, at least two active pixels configured to detect light radiation in at least partially different spectral ranges, and each darkening pixel configured to generate at least one photodetector signal independently of illumination to the darkening pixel; and - at least one readout device configured to measure the photodetector signals and generate at least one spectral data item; and - An evaluation device comprising at least one processor and at least one storage device, wherein the storage device is configured to store at least one classification model comprising a set of different classes, each class referring to at least one spectral characteristic, and the classification model is configured to classify at least one input data item into a class; and at least one conversion function configured to convert a spectral data item into an input data item applicable to the classification model. The evaluation device is configured to generate at least one measurement information item by applying the classification model and the conversion function to the spectral data item.

[0011] Furthermore, Patent Document 8 (EP 3 961 826 A1) discloses a light irradiation device comprising a light source configured to emit primary light, a first phosphor that absorbs the primary light and converts it into a first wavelength-converted light having a longer wavelength than the primary light, and a second phosphor that absorbs the first light and converts it into a second wavelength-converted light having a longer wavelength than the first light. The first wavelength-converted light is fluorescence having light components across the entire wavelength range from 700 nm to 800 nm. The second wavelength-converted light is fluorescence in which the wavelength range where the fluorescence intensity shows its maximum value is from 380 nm to less than 700 nm. The first wavelength-converted light has an afterglow time that is 1 / 10 longer than that of the second wavelength-converted light. [Prior art documents] [Patent Documents]

[0012] [Patent Document 1] US 2010 / 208261 A1 [Patent Document 2] U.S. Patent No. 8,164,050 B2 [Patent Document 3] US Patent No. 7,061,618 B2 [Patent Document 4] U.S. Patent No. 5,475,221A [Patent Document 5] US 2021 / 293620 A1 [Patent Document 6] WO 2018 / 203831 A1 [Patent Document 7] WO 2023 / 052608 A1 [Patent Document 8] EP 3 961 826 A1

[0013] Despite the advantages achieved by known methods and devices, in the field of spectroscopy and spectroscopic devices, particularly spectroscopy in the near-infrared region, several technical problems remain. A spectrometer system that combines an LED and a phosphor emission coating as a light source may have a reduced conversion efficiency in a specific wavelength range such as the infrared wavelength range, and as a result, a significant amount of illumination may occur outside the intended target wavelength. Therefore, since spectroscopic information cannot be obtained from these wavelengths, the optical power in this wavelength range is generally wasted. Furthermore, generally, changing environmental conditions and / or operating conditions can cause measurement problems in a spectroscopic system. For example, changes in the environmental temperature and / or operating temperature of a detector can cause signal drift because the spectroscopic sensitivity of most detectors strongly depends on the detector temperature. Without correction, the measurement can be affected by detector drift. Detector drift can cause a shift in the measured spectrum during a single measurement and / or between multiple consecutive measurements, particularly in the near-infrared spectral region. Summary of the Invention Problems to be Solved by the Invention

[0014] Therefore, it is desirable to provide a method and device that at least partially solve the above technical problems and at least substantially avoid the disadvantages of known methods and devices. In particular, an object of the present invention is to provide a spectroscopic device that can at least partially compensate for varying environmental conditions and / or operating conditions and a method for obtaining spectroscopic information regarding at least one object.

[0015] This problem is addressed by a spectrometer device for obtaining spectroscopic information regarding at least one object, a method for obtaining spectroscopic information regarding at least one object, and a computer program and a computer-readable storage medium for executing the method with the features of the independent claims. Advantageous embodiments that can be realized alone or in any combination are described in the dependent claims and throughout the specification.

[0016] In a first aspect of the present invention, a spectrometer device for acquiring spectral information relating to at least one object is disclosed.

[0017] As used herein, the term “spectrometer” is a broad term, given in the ordinary sense as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. Specifically, the term may refer to, but is not limited to, an optical device configured to acquire at least one spectral piece of information for at least one object. Specifically, the at least one spectral piece of information may refer to at least one optical property or optically measurable property determined as a function of wavelength at one or more different wavelengths. More specifically, the optical property or optically measurable property, and the at least one spectral piece of information, may relate to at least one property characterizing at least one of transmission, absorption, reflection, or emission of at least one object itself, or after external light irradiation. The at least one optical property may be determined for one or more wavelengths. A spectrometer device may, in particular, form a device capable of recording signal intensity with respect to wavelengths corresponding to a spectrum or its divisions (e.g., wavelength intervals). Here, the signal intensity may, in particular, be provided as an electrical signal usable for further evaluation.

[0018] The spectrometer apparatus may be, or may include, an apparatus capable of measuring, for example, at least one spectrum (e.g., for measuring spectral flux), particularly as a function of wavelength or detection wavelength. The spectrum may be acquired, for example, in absolute units or relative units (e.g., in relation to at least one reference measurement). Thus, for example, the acquisition of at least one spectrum may be performed, in particular, for measuring spectral flux (unit: W / nm) or for measuring the spectrum of at least one reference material (unit: 1), which may describe the properties of the material, such as reflectance with respect to 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 literature), and / or a reference apparatus.

[0019] 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 an absorption spectrometer and / or a transmission spectrometer, or may include both. In particular, spectral measurement by the spectrometer device may include absorption measurement in a transmission configuration. Specifically, the spectrometer device may be configured for absorption measurement in a transmission configuration. However, as described above, other types of spectrometer devices are also feasible.

[0020] At least one spectrometer device may, in particular, include at least one light source, as described below, which may be, for example, at least one of at least one tunable light source, a light source having at least one fixed emission wavelength, and a broadband light source. The spectrometer device further comprises at least one detector device, as outlined in more detail below, which is configured to detect light such as light transmitted, reflected, or emitted from at least one object, and / or light guided from the light source to the detector device without interacting with the object. The interaction of light with the object may include at least one of transmitted light, reflected light, or light emitted from at least one object. The spectrometer device may further include at least one wavelength-selective element, for example, at least one diffraction grating, prism, or filter (for example, a variable-length filter whose transmission characteristics change over its lateral extension), as outlined in more detail below. This wavelength-selective element may be used to separate incident light into spectra of constituent wavelength signals, the intensity of which can be determined using a detector such as a detector having a detector array, as outlined below.

[0021] In particular, the spectrometer apparatus may be a portable spectrometer apparatus. The term “portable” as used herein is a broad term, given in the ordinary sense as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. Specifically, this term may, but is not limited to, the characteristic that at least one object is movable by human power by a single user. Specifically, an object characterized by the term “portable” may weigh no more than 10 kg, specifically no more than 5 kg, more specifically no more than 1 kg, or no more than 500 g. Additionally or alternatively, the dimensions of an object characterized by the term “portable” may not exceed 0.3 m in any dimension, specifically no more than 0.2 m in any dimension. Specifically, the volume of the object may be 0.03 m³. 3 Specifically, 0.01m 3 More specifically, 0.001m 3 Below, or 500mm 3 The following are also possible. For example, the dimensions of a portable spectrometer may be, for instance, 10 mm x 10 mm x 5 mm. Specifically, the portable spectrometer may be part of a mobile device or be attachable to a mobile device such as a notebook computer, tablet, mobile phone (e.g., smartphone), smartwatch, and / or wearable computer (also referred to as "wearable," e.g., a computer worn on the body such as a wristband or watch). In particular, the weight of the spectrometer, specifically the portable spectrometer, may be in the range of 1 g to 100 g, and more specifically, in the range of 1 g to 10 g.

[0022] As used herein, the term “spectral information” (also referred to as “spectral information” or “item of spectral information”) is a broad term, given in the ordinary sense as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. Specifically, the term may represent, without limitation, a specific item of information relating to at least one object and / or radiation emitted from at least one object, i.e., information characterizing at least one optical property of the object. More specifically, the term may represent at least one item of information characterizing (e.g., modifying and / or quantifying) at least one of the transmission, absorption, reflection and emission of at least one object. As an example, at least one spectral information may include at least one intensity information, e.g., information relating to the intensity of light transmitted, absorbed, reflected, or emitted by the object, for example, as a function of one or more wavelengths, e.g., wavelength or wavelength subrange over a wavelength range. Specifically, the intensity information may correspond to, or be derived from, signal intensity, in particular electrical signal, recorded by a spectrometer with respect to the wavelength or wavelength range of the spectrum.

[0023] The spectrometer may be configured to acquire at least one spectrum or portion of a spectrum of detected light propagating from the object to the spectrometer. The spectrum may describe, for example, the spectral flux, which is a radiometric unit given in units of watts per nanometer (W / nm), or other units as a function of the wavelength of the detected light. Thus, the spectrum may describe, for example, the optical power of light in a specific wavelength band in the near-infrared (NIR) spectral range. The spectrum may include one or more optical variables as a function of wavelength, such as power spectral density, electrical signals derived by optical measurements, etc. As an example, the spectrum may show the power spectral density and / or spectral flux (transmittance and / or reflectance of the object (especially the sample), etc.) of the object (e.g., sample) as a relative value to a reference sample.

[0024] The spectrum may, for example, include at least one measurable optical variable or characteristic of the detected light and / or object (particularly as a function of the illumination light and / or detected light). For example, the at least one measurable optical variable or characteristic may include at least one radiometric quantity, which may include, for example, spectral density, power spectral density, spectral flux, radiant flux, radiant intensity, spectral radiant intensity, illuminance, spectral illuminance, etc. Specifically, for example, a spectrometer, particularly a detector, may measure watts per square meter (W / m²). 2 Irradiance in units of watts per square meter per nanometer (W / m²). More specifically, watts per square meter per nanometer. 2 The spectral irradiance can be measured in units of ( / nm). Based on the measured quantity, the spectral flux (W / nm) and / or radiant flux (W) can be determined (e.g., calculated), taking into account the detector area.

[0025] As used herein, the term “subject matter” is a broad term, given in the ordinary sense as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. Specifically, the term may, without limitation, represent any object selected from living and non-living objects. Thus, as an example, at least one subject matter may include one or more articles and / or one or more parts of articles, where at least one article or at least one part thereof may include at least one component capable of providing a spectrum suitable for investigation. Additionally or alternatively, the subject matter may be, or include, one or more living organisms and / or one or more parts thereof, e.g., one or more body parts of humans (e.g., users) and / or animals. The subject matter may, in particular, include one or more samples that can be analyzed completely or partially by spectroscopy. As an example, the subject matter may be, or may include, one or more of the following: human or animal skin; food such as fruit; plastics and textile products.

[0026] The spectrometer equipment includes the following: i. At least one light source for generating illumination light for illuminating an object, 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; ii. At least one broadband detector for detecting detection light, specifically detection light from an object and / or detection light guided from a light source to a broadband detector without interaction with the object, wherein the detection light is detected in a spectral range that at least partially includes the spectral range of primary light and the spectral range of secondary light, and the broadband detector is configured to generate at least one primary detector signal when it detects detection light within the spectral range of primary light, and further configured to generate at least one secondary detector signal when it detects detection light within the spectral range of secondary light; iii. At least one evaluation unit for evaluating the primary and secondary detector signals generated by a broadband detector, determining the responsiveness information of the broadband detector from either the primary or secondary detector signal, and deriving spectral information of an object from the other of the primary or secondary detector signal, taking into account the responsiveness information of the broadband detector.

[0027] As used herein, the term “light” is a broad term, given in the ordinary sense as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. Specifically, the term may refer to, but is not limited to, electromagnetic radiation in one or more of the infrared, visible light, and ultraviolet spectral regions. In this specification, “ultraviolet spectral region” generally refers to electromagnetic radiation with wavelengths from 1 nm to 380 nm, preferably from 100 nm to 380 nm. Furthermore, in part in accordance with the standard ISO-21348 in effect as of the date of this specification, 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. Of this range, the 760 nm to 1.5 μm range is usually called the "near-infrared spectral range" (NIR), the 1.5 μm to 15 μm range is called the "mid-infrared spectral range" (MidIR), and the 15 μm to 1000 μm range is called the "far-infrared spectral range" (FIR). The light used for typical purposes of the present invention is preferably light in the infrared (IR) spectral range, more preferably near-infrared (NIR) and / or mid-infrared spectral range (MidIR), particularly light with wavelengths of 1 μm to 5 μm, preferably 1 μm to 3 μm. This is because many material properties and chemical compositional properties of objects can be derived from the near-infrared spectral region. However, it should be noted that spectroscopy in other spectral regions is also possible and falls within the scope of the present invention.

[0028] As used herein, the term “light source” is a broad term, given in the ordinary sense as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. The term may, in particular, refer to any device that generates or provides light in the sense defined above. Specifically, a light source may be an electric light source, such as an electrically driven light source, or may include at least one electric light source. The light source may be located within the housing of the spectrometer apparatus as part of the spectrometer apparatus. Alternatively, or additionally, at least one light source may be located outside the housing, for example, as a separate light source. The light source may be located away from the object and illuminate the object remotely.

[0029] In spectroscopy, it is necessary to distinguish between various sources and paths of light. In the context of this invention, first, the light propagating from the light source to the object is referred to as "irradiation light" or "illumination light." Next, the light propagating from the object to the broadband detector is referred to as "detection light." For example, detection light may include at least one of illumination light reflected by the object, illumination light scattered by the object, illumination light transmitted by the object, or emission light generated by the object (e.g., phosphorescence or fluorescence generated by the object after optical, electrical, or acoustic excitation of the object by illumination light, etc.). Therefore, in this example, detection light may be generated directly or indirectly through illumination of the object by illumination light. Additionally, or instead, detection light may include light generated by the light source, specifically primary light, secondary light, and / or a combination of primary and secondary light, which may be guided to the broadband detector via the first optical path without interacting with the object.

[0030] As used herein, the term “irradiate” is a broad term, given in the ordinary sense as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. In particular, the term may refer to, but is not limited to, the process of exposing at least one element to light.

[0031] Furthermore, as will be described later, it is possible to distinguish between various light sources, such as primary and secondary light sources, even within the light source itself. Therefore, as will be described later, "primary light" (also called "excitation light") may be generated by at least one primary light source, such as a light-emitting diode, and then converted into "secondary light" through, for example, light conversion by a light-emitting material via one or more phosphor materials. Illumination light may include at least partially primary light and secondary light. Specifically, illumination light may include the portion of primary light generated by the light-emitting diode that was not converted into secondary light by the light-emitting material due to, for example, low conversion efficiency of the light-emitting material, and secondary light.

[0032] As described above, the light source includes at least one light-emitting diode and at least one light-emitting material for converting the primary light generated by the light-emitting diode into secondary light.

[0033] As used herein, the terms “light-emitting diode” or “LED” are broad terms, given the ordinary meanings that are commonly understood by those skilled in the art, and are not limited to any special or customized meanings. Specifically, the term may refer to, but is not limited to, a photoelectron semiconductor device that is capable of emitting light when an electric current is passed through it. This photoelectron semiconductor device may be configured to produce light by various physical processes, such as spontaneous emission, stimulated emission, or the decay of metastable excited states. Thus, as an example, a light-emitting diode may include one or more of the following: a light-emitting diode based on spontaneous emission (especially organic light-emitting diodes), a light-emitting diode based on superluminescence (sLED), or a laser diode (LD). Hereafter, the abbreviation “LED” will be used for all types of light-emitting diodes without limiting possible embodiments of the light-emitting diode to any of the aforementioned physical principles or configurations. Specifically, an LED may comprise at least two layers of semiconductor material, where light is generated at at least one interface between the at least two layers of semiconductor material, particularly by the recombination of positive and negative charges (e.g., electron-hole recombination). At least two semiconductor material layers may have different electrical properties; for example, at least one layer may be an n-type doped semiconductor material and at least one layer may be a p-type doped semiconductor material. Therefore, as an example, an LED may include at least one pn junction and / or at least one pin configuration. However, it should be noted that other device structures are also possible. The at least one semiconductor material may be, in particular, at least one inorganic semiconductor material, or may include at least one inorganic semiconductor material. However, it should be noted that organic semiconductor materials may be used additionally or as a substitute.

[0034] In general, an LED may convert an electrical current into light, specifically primary light, and more specifically blue primary light, which will be discussed later. Therefore, an LED may be a blue LED in particular. An LED may be configured to generate primary light (also known as "pump light"). Therefore, an LED may also be called a "pump LED". An LED may include at least one LED chip and / or at least one LED die. Therefore, the semiconductor element of an LED may include an LED bare chip.

[0035] Various types of LEDs suitable for generating primary light are well known to those skilled in the art and are applicable to the present invention. Specifically, pn diodes may be used. As an example, one or more LEDs selected from indium gallium nitride (InGaN) based LEDs, GaN based LEDs, InGaN / GaN alloy based LEDs, combinations thereof, and / or other LEDs may be used. Additionally, or instead, quantum well LEDs may also be used, for example, one or more InGaN-based quantum well LEDs may be used. Additionally, or instead, superluminescent LEDs (sLEDs) and / or quantum cascade lasers may also be used.

[0036] As used herein, the term “luminescence” is a broad term, given in the ordinary sense as commonly understood by those skilled in the art, and is not limited to any particular or restrictive meaning. Specifically, the term may refer to the process of spontaneous light emission by a substance that is not caused by heat. In particular, luminescence may refer to cold radiation. More specifically, luminescence may be initiated or excited by irradiation with light, in which case the luminescence may also be referred to as “photo-excited luminescence.” In the context of this invention, the property of a material having the ability to emit light is indicated by the adjective “luminescence.” At least one luminescent material may specifically be a photo-excited material, i.e., a material having the ability to emit light after absorbing a photon or excitation light. Specifically, a luminescent material may have a positive Stokes shift, which generally refers to the fact that secondary light is redshifted relative to primary light.

[0037] Therefore, at least one luminescent material may form at least one converter (also called a light converter) that converts primary light into secondary light, and the secondary light has spectral characteristics different from those of the primary light. Specifically, the spectral width of the secondary light may be wider than that of the primary light, and / or the central wavelength of the secondary light may be shifted (especially red-shifted) compared to the primary light. Specifically, at least one luminescent material may exhibit absorption in the ultraviolet and / or blue spectral regions and emit light in the near-infrared and / or infrared spectral regions. Therefore, generally, the luminescent material or converter may form at least one component that converts primary light or excitation light (especially in the blue spectral region) into light of a longer wavelength (e.g., in the near-infrared or infrared spectral region) in LEDs, especially phosphor LEDs.

[0038] Various types of conversion and / or emission are known and can be used in the context of the present invention. Specifically, the conversion can occur via dipole-allowed transitions (also called fluorescence) in the luminescent material and / or via dipole-forbidden transitions (therefore long-lived and often also called phosphorescence) in the luminescent material.

[0039] Therefore, the luminescent material may in particular form at least one converter or light converter. The luminescent material may form at least one of a converter platelet, a luminescent (especially fluorescent) coating on an LED, and a phosphor coating on an LED. The luminescent material may include, for example, one or more of the following materials: cerium-doped YAG (YAG:Ce 3+ , or Y3Al5O 12 :Ce 3+ ); rare-earth-doped sialon; copper- and aluminum-doped zinc sulfide (ZnS:Cu,Al).

[0040] The light source may include a phosphor light-emitting diode. Specifically, the LED and the light-emitting material may be integrated to form a so-called "phosphor LED." Therefore, the terms "phosphor light-emitting diode" or "phosphor LED" as used herein are broad terms, given the meaning that a person skilled in the art would ordinarily understand, and are not limited to any special or customized meaning. In particular, the term may refer to a combination of at least one light-emitting diode configured to produce primary light or pumping light, and at least one light-emitting material (also referred to as a "phosphor") configured to convert the primary light produced by the light-emitting diode into light. A phosphor LED may form a packaged LED light source comprising an LED die (e.g., a blue LED emitting blue pumping light) and a phosphor (e.g., configured to convert primary light or blue light into light with different spectral characteristics, particularly near-infrared light) that covers the LED all or partially. Generally, a phosphor LED may be enclosed in a single housing or may be unenclosed. Therefore, the LED and at least one light-emitting material for converting the primary light generated by the light-emitting diode are housed in a common housing. However, alternatively, the LED may be a bare LED without a housing, or it may be completely or partially covered with a light-emitting material, which can be achieved, for example, by placing one or more layers of light-emitting material on the LED die. Phosphor LEDs can generally form a light-emitting body or light source on their own.

[0041] In a light source, particularly a phosphor LED, at least one light-emitting material can be positioned relative to a light-emitting diode (LED) such that heat transfer from the LED to the light-emitting material is possible. More specifically, the light-emitting material can be positioned such that heat transfer is possible by either thermal radiation or thermal conduction, or both (more preferably by thermal conduction). Thus, for example, the light-emitting material can maintain thermal and / or physical contact with the LED. For example, the light-emitting material can form one or more coatings or layers in contact with or in close proximity to one or more of the semiconductor materials of the LED. In general, the light-emitting material and the LED may be thermally coupled. As used herein, the terms “thermally coupled” or simply “thermally coupled” are broad terms and are given the ordinary meanings that are commonly understood by those skilled in the art, and are not limited to any special or customized meanings. Specifically, the term may, but is not limited to, the temperature difference (0.1K to 5K, particularly 0.1K to 1K, more specifically 0.1K to 0.5K) that exists between the LED and the light-emitting material during the operation of the light source. In other words, given the primary and secondary power spectral densities, a single temperature can be assigned to both the light-emitting diode and the phosphor material, i.e., the light source. The advantage of thermal coupling is that the spectra of the light-emitting diode and the phosphor material exhibit separate but characteristic temperature dependencies. A further advantage is that a single temperature assigned to the light source can be determined using either spectrum or a portion thereof, and the spectral information of the object can be derived from the other spectrum using this single temperature of the light source. This makes it possible to take temperature information regarding the light source into account.

[0042] At least one light-emitting material can, in particular, form at least one layer. In general, various alternatives for arranging the light-emitting material on a light-emitting diode can be realized individually or in combination. Firstly, a phosphor material (e.g., at least one layer of phosphor material, e.g., phosphor) can be placed directly on the light-emitting diode, also known as "direct attachment," which includes cases where no material is sandwiched between the LED and the phosphor material, or where one or more transparent materials (especially materials transparent to primary light) are sandwiched in between. Thus, as an example, a coating layer of light-emitting material can be placed directly or indirectly on the LED. Additionally or alternatively, the light-emitting material can form, for example, at least one transducer body (e.g., at least one transducer disk), and this transducer body can be placed on the LED, for example, by fixing the transducer body to the LED with adhesive. Additionally or alternatively, the phosphor may be remotely arranged, in which case the primary light from the LED must pass through an intermediate optical path before reaching the phosphor. This arrangement may also be called "remote placement" or "remote phosphor." For example, in remote placement, the light-emitting material can form a solid body such as a disk or converter disk, or a converter body. Furthermore, in the case of remote placement, the light-emitting material may also be in the form of a coating. In particular, it is possible to coat a light-transmitting object (e.g., a thin glass substrate, module window, etc., made of / or fabricated from glass or plastic) with a phosphor. Alternatively, a reflective surface can also be coated with a phosphor. This may be a flat or rough surface mirror made of / or fabricated from a high refractive index material (e.g., silicon), 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, diffraction gratings, mirrors, apertures, or combinations thereof, may be placed in the intermediate optical path. Specifically, it is possible to place an optical system with image-forming properties in the intermediate optical path between the LED and the light-emitting material. This allows, for example, the primary light to be focused or concentrated on the converter body.

[0043] The primary light may be located at least partially 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 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, where 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, an LED may include a blue LED whose primary emission range is located at least partially in the spectral range of 420 nm to 460 nm, specifically in the spectral range of 440 nm to 455 nm, and even more specifically at 440 nm.

[0044] If the primary light generated by a light-emitting diode is not converted into secondary light by the light-emitting material, it lies at least partially 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 lie in the spectral range between the first and second wavelengths, where the first wavelength can be selected from 380 nm, 420 nm, and 440 nm, and the second wavelength can be selected from 1000 nm, 940 nm, 830 nm, 460 nm, and 455 nm.

[0045] The secondary light may be located at least partially 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, the secondary light may be located in the spectral range between the first wavelength and the second wavelength, where the first wavelength includes at least one of 1 μm or 1.5 μm, and the second wavelength is selected from 5 μm, 3 μm, and 1.5 μm.

[0046] As described above, the spectrometer apparatus comprises at least one broadband detector for detecting detection light in a spectral range that at least partially includes the spectral ranges of primary and secondary light. The verb “detect” as used herein is a broad term, given in the ordinary sense as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. In particular, the term may represent at least one process of qualitatively and / or quantitatively determining, measuring, or monitoring at least one parameter, such as a physical parameter, a chemical parameter, or a biological parameter. Specifically, the physical parameter may be an electrical parameter, or may include an electrical parameter. Accordingly, the term “detector” as used herein is a broad term, given in the ordinary sense as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. The term may represent any apparatus configured to qualitatively and / or quantitatively determine, measure, or monitor at least one parameter, such as a physical parameter, a chemical parameter, or a biological parameter, without particular limitation. The detector may be configured to generate at least one detector signal, more specifically at least one electrical detector signal (such as an analog detector signal and / or a digital detector signal), where the detector signal provides information about at least one parameter measured by the detector. The detector signal may be provided directly or indirectly from the detector to the evaluation unit, so the detector and the evaluation unit may be connected directly or indirectly. The detector signal may be used as a "raw" detector signal, or it may be used after being processed or preprocessed by filtering, etc. Accordingly, the detector may include at least one processing unit and / or at least one preprocessing unit (including at least one of an amplifier, an analog-to-digital converter, an electrical filter, a Fourier transform, etc.).

[0047] As used herein, the term “broadband detector” is a broad term and is given in the ordinary sense as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. The term may, in particular, represent, but is not limited to, at least one detector in the sense described above, which is configured to detect light in multiple of the infrared, visible, and ultraviolet spectral regions. Specifically, a broadband detector may be configured to detect detected light in a first region of the visible spectral range and a second region of the infrared spectral range, where the second region is preferably adjacent to the first region. However, it is also possible to use a second region separated from the first region. A broadband detector may be configured to detect detected 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.

[0048] A broadband detector may be configured to detect light propagating from an object to a spectrometer, and more specifically to the broadband detector of the spectrometer, and / or detection light (referred to as "detection light" according to the aforementioned nomenclature) guided from a light source to the broadband detector without interacting with the object. Thus, specifically, the broadband detector may be at least one optical detector, or may include at least one optical detector. The optical detector may be configured to determine at least one optical parameter, such as the intensity and / or power of light irradiated onto at least one photosensitive area of ​​the broadband detector. More specifically, the photodetector may include at least one photoelectric element and / or at least one photosensor, such as at least one of a photodiode, photocell, photoresistive element, phototransistor, thermoelectric element, photoacoustic sensor, pyroelectric element, photomultiplier tube, and bolometer. Accordingly, the broadband detector may be configured to generate at least one detector signal, more specifically at least one electrical detector signal, in the sense described above, and to provide information about at least one optical parameter, such as the power and / or intensity of the light illuminating the broadband detector or the sensitive region of the broadband detector.

[0049] A broadband detector may comprise a single photosensitive element or region, or multiple photosensitive elements or regions. Specifically, a broadband detector may comprise or comprise at least one detector array, more specifically an array of photosensitive elements, as outlined in more detail below. Each photosensitive element may comprise at least one photosensitive region configured to generate an electrical signal in response to the intensity of incident light, which may be supplied in particular to an evaluation unit, which will be described in detail later.

[0050] The photosensitive region of each photosensitive element may be a single, uniform photosensitive region configured to receive incident light irradiated onto each individual photosensitive element. However, other arrangements of photosensitive elements are also possible.

[0051] An array of photosensitive elements may be designed to generate detector signals (preferably electronic signals) related to the intensity of incident light irradiated onto each individual photosensitive element. These detector signals can be analog and / or digital. Electronic signals from adjacent pixelated sensors can be generated accordingly, simultaneously or sequentially in time. For example, during row scanning or line scanning, it is possible to generate a sequence of electronic signals corresponding to a sequence of individual photosensitive elements arranged in a row. Furthermore, each individual photosensitive element may preferably be an active pixel sensor adaptable to amplify its electronic signal before supplying it to an 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 signal.

[0052] If the broadband detector includes an array of photosensitive elements, the broadband detector may be selected from, for example, any known pixel sensor, particularly pixelated organic camera elements, preferably pixelated organic camera chips, or pixelated inorganic camera elements, preferably pixelated inorganic camera chips, more preferably CCD chips or CMOS chips, which are currently commonly used in various cameras. As another option, the broadband detector may generally be a photoconductor, particularly an inorganic photoconductor, particularly PbS, PbSe, InSb, or HgCdTe, or may include them. As yet another option, it may be a photodiode, particularly one containing at least one of Si, Ge, InGaAs, or extended InGaAs, or may include them. As yet another alternative, it may include at least one pyroelectric, bolometer, or thermofil type detector element. Thus, a camera chip having a 1×N pixel or M×N pixel matrix may be used here, for example, where M is less than 10 and N is in the range of 1 to 50, preferably 2 to 20, more preferably 5 to 10. Furthermore, a monochrome camera element, preferably a monochrome camera chip, may also be used, and a different monochrome camera element may be selected for each optical sensor, particularly depending on the wavelength which changes along the sequence of optical sensors.

[0053] Therefore, this array is adaptable to provide multiple electrical signals generated by the photosensitive regions of the photosensitive elements constituting the array. The electrical signals provided by the array of the spectrometer are transferred to the evaluation unit.

[0054] As used herein, the term “primary detector signal” is a broad term, given in the ordinary sense as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. In particular, the term may, but may not, refer to at least one detector signal in the sense described above, generated by a broadband detector when detecting detection light within the spectral range of primary light.

[0055] Similarly, the term “secondary detector signal” as used herein is a broad term, given its usual meaning as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. In particular, the term may, but is not limited to, the at least one detector signal in the aforementioned sense, generated by a broadband detector when detecting detected light within the spectral range of secondary light.

[0056] A broadband detector may include multiple detector elements, such as the multiple photosensitive elements described above, for detecting detection light within the spectral ranges of primary and secondary light. For example, a broadband detector may include a pixelated broadband detector that includes multiple photosensitive pixels or elements, as described above. For example, 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 when it detects detection light within the spectral range of primary light. The second detector element may be configured to generate a secondary detector signal when it detects detection light within the spectral range of secondary light. Each detector element may include a photosensitive material selected from at least one of PbS, PbSe, InSb, or HgCdTe. Each detector element of the multiple detector elements may include the same photosensitive material, or it may instead include different photosensitive materials. Different materials for the detector elements may be used, in particular, when different detector elements are expected to have different wavelength ranges and / or different sensitivities in different use cases.

[0057] Alternatively, the broadband detector may be a single detector comprising a photosensitive material selected from at least one of PbS, PbSe, InSb, or HgCdTe. Another option is that the broadband detector may be a single detector comprising a photodiode, particularly one comprising at least one of Si, Ge, InGaAs, or ext. InGaAs.

[0058] The spectrometer apparatus may further include at least one drive unit for electrically driving a light source. As used herein, the term “drive” is a broad term, given in the ordinary sense as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. Specifically, it may refer to, but is not limited to, the process of providing either or both of at least one control parameter and / or electrical power to another device. Accordingly, as used herein, the term “drive unit” is a broad term, given in the ordinary sense as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. The term may, in particular, refer to any device or combination of devices configured to provide at least one control parameter and / or electrical power to another device (in this embodiment, at least one light source). For example, a drive unit may be configured to measure and / or control one or more electrical parameters of the power supplied to a light source, specifically at least one light-emitting diode (LED). As an example, a drive unit may be configured to supply an electrical current to an LED, and in particular to control the electrical current flowing through the LED. Here, as an example, the drive unit may be configured to adapt and measure the voltage supplied to the LED, which is required to achieve a specific current flowing through the LED. The drive unit may specifically include one or more of the following: a current source, a voltage source, a current measuring device (such as an ampere meter), a voltage measuring device (such as a voltmeter), and a power measuring device. Specifically, the drive unit may include at least one current source for supplying at least one predetermined current to the LED, which may be configured to adjust or control the voltage applied to the LED to generate the predetermined current. The drive unit may, for example, include one or more electrical components such as an integrated circuit for driving a light source. The drive unit may be fully or partially integrated with the light source, or it may be separate from the light source.

[0059] The drive unit may be configured to drive the light-emitting diode at at least one drive frequency. As used herein, the term “drive frequency” is a broad term and is given the ordinary meaning that is commonly understood by those skilled in the art, and is not limited to any special or customized meaning. Specifically, the term may, but is not limited to, a quantitative measurement of the number of drive repetitions of the light source per unit of time. Specifically, the drive frequency may represent the number of drive repetitions of the light source per second. The drive of a light source, i.e., the process of supplying the light source with either or both of at least one control parameter and / or electrical power, at a first value that causes the light source to emit light and a second value that does not cause the light source to emit light, may be referred to as a single drive repetition.

[0060] Furthermore, the driving frequency may exceed the reciprocal of the time constant τ of the light-emitting material. The term “time constant” as used herein is a broad term, given in the usual sense as commonly understood by those skilled in the art, and is not limited to any special or specific meaning. Specifically, the term may, but is not limited to, a typical time interval describing the equilibrium state, particularly the reorganization of the equilibrium state of a light-emitting material, when at least one operating parameter is changed. The time constant τ may also describe the delay between the absorption of at least one primary photon by the light-emitting material and the emission of at least one secondary photon by the light-emitting material. This delay may be characterized by a so-called “characteristic time constant” τ (also called the time constant, decay time, or saturation time). When used in processes where the rate or probability of a process, such as photon emission, is proportional to the occupancy rate of one or more states or process states, the occupancy rate usually changes exponentially. In these processes, the time constant τ may determine the 1 / e time of the process. In light-emitting materials or converters, particularly phosphors, two different time constants may arise. Firstly, the first time constant, which may depend on the intensity of the excitation light, describes the typical time at which the emission of converted light reaches a saturation state, such as a "growth constant." Secondly, the second time constant represents the typical time of the afterglow of the light-emitting material or converter, and is referred to as the "decay constant" or "decay." The drive frequency may be set to exceed the reciprocal of the decay constant of the light-emitting material. Furthermore, the evaluation unit may be configured to distinguish between the primary detector signal and the secondary detector signal using a Fourier transform, particularly the fast Fourier transform. Accordingly, the spectrometer apparatus may be configured to perform pulse width modulation of the light source using the drive unit.

[0061] As described above, the spectrometer apparatus includes at least one evaluation unit for evaluating the primary and secondary detector signals generated by the broadband detector. The term “evaluate” as used herein is broad and given its ordinary meaning as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. Specifically, this term may represent, but is not limited to, a process of processing at least one first information item to generate at least one second information item. Accordingly, the term “evaluation unit” as used herein is broad and given its ordinary meaning as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. Specifically, this term may represent, but is not limited to, any apparatus or combination of apparatus configured to evaluate or process at least one first information item and generate at least one second information item therefrom. Accordingly, specifically, an evaluation unit may be configured to process at least one input signal and generate at least one output signal therefrom. The at least one input signal may, for example, include at least one primary detector signal and at least one secondary detector signal, provided directly or indirectly by the broadband detector.

[0062] As an example, the evaluation unit may be one or more integrated circuits (e.g., one or more application-specific integrated circuits (ASICs)) and / or one or more data processing devices (e.g., one or more computers, digital signal processing devices (DSPs), field-programmable gate arrays (FPGAs), preferably one or more microcomputers and / or microcontrollers), or may include them. Additional components may include one or more preprocessing devices and / or data acquisition devices (e.g., one or more devices for receiving and / or preprocessing detector signals, e.g., one or more A / D converters and / or one or more filters). Furthermore, the evaluation unit may include one or more data storage devices. Furthermore, the evaluation unit may include one or more interfaces, e.g., one or more wireless interfaces and / or one or more wired interfaces.

[0063] The evaluation unit may be configured to run at least one computer program. For example, at least one computer program may perform or support steps to generate items of information. For example, one or more algorithms may be implemented that take primary and secondary detector signals as input variables, determine broadband detector responsiveness information, and perform predetermined transformations to derive spectral information about an object. This makes it possible to derive at least one spectral piece of information describing at least one characteristic of the object (in this case, broadband detector responsiveness information is considered). For this purpose, the evaluation unit may particularly include at least one data processing device, in particular an electronic data processing device, also referred to as a processor, which may be designed to generate desired information by evaluating primary and secondary detector signals. The evaluation unit may generate the necessary information using any process, such as calculation and / or the use of at least one stored and / or known relation. The evaluation unit may particularly be configured to perform at least one digital signal processing (DSP) technique, including at least one Fourier transform, on the primary detector signal or the secondary detector signal derived therefrom. Additionally, or alternatively, the evaluation unit may be configured to perform one or more further digital signal processing techniques on the primary detector signal or the secondary detector signal derived therefrom, including, for example, winding, filtering, Gerzel algorithm, cross-correlation, and autocorrelation. In addition to the primary and secondary detector signals, one or more further parameters and / or information items may influence the relationship. The relationship is determined or can be determined empirically, analytically, or semi-empirically. As an example, the relationship may include a model or calibration curve, at least one set of calibration curves, at least one function, or at least one combination of the aforementioned possibilities. One or more calibration curves may be stored, for example, in the form of a set of values ​​and their associated function values, for example, in a data storage device and / or table. However, alternatively or additionally, at least one calibration curve may also be stored, for example, in a parameterized form and / or as a functional equation.Separate relational expressions may be used to process the primary and secondary detector signals into information items. Alternatively, at least one unified relational expression for processing the primary and secondary detector signals is also possible. Various possibilities are conceivable, and they can be combined. The evaluation unit is, - To evaluate the primary and secondary detector signals generated by the broadband detector, - To determine the response information of the broadband detector from either the primary or secondary detector signal, - In order to derive spectral information of the object from either the primary or secondary detector signal, taking into account the response information of the broadband detector, It is composed of the following.

[0064] The term “responsiveness information” as used herein is a broad term and is given the ordinary and customary meaning that is commonly understood by those skilled in the art, and is not limited to any special or customized meaning. In particular, the term may, but is not limited to, specific information items that characterize the input-output correlation of a detection device. For the purposes of the present invention, responsiveness information may represent specific information items that characterize the input-output correlation of a broadband detector. Specifically, responsiveness information may include at least one information item that characterizes the correlation between the electrical output of the broadband detector, such as a detector signal, and the optical input, such as illumination of the broadband detector by detection light. Responsiveness information may depend on one or more of the wavelength of the detection light and the characteristics of the broadband detector (such as intrinsic and / or extrinsic material properties). Responsiveness information may be derivable from the detector signal, specifically one or more of the primary and secondary detector signals. Responsiveness information may be used to correct the detector signal for changing environmental and / or operating conditions, such as changes in detector temperature. Additionally, or instead, responsiveness information may be used to calibrate the detector signal, for example, against a known calibration standard. For example, the primary detector signal may be used to determine responsiveness information, and the secondary detector signal may be used to derive spectral information of the object. In general, fluctuations in the detector signal due to temperature fluctuations in the light source (especially phosphor LEDs) may be smaller than fluctuations in the detector signal due to temperature fluctuations in a broadband detector (especially when considering short periods of time). In this example, the primary detector signal may be more stable than the secondary detector signal. Therefore, the primary detector signal can be used to compensate for drift in the secondary detector signal due to temperature fluctuations.

[0065] The spectrometer apparatus may also include the following: vi at least one first optical path, which may be configured to allow at least a portion of the primary light or illumination light to propagate from the light source to the broadband detector without interacting with the object; v: At least one second optical path, the second optical path is configured to interact with the object at least once as the illumination light propagates from the light source to the broadband detector.

[0066] As used herein, the term “optical path” is a broad term, given in the sense that a person skilled in the art would ordinarily understand, and is not limited to any special or customized meaning. In particular, the term may, but is not limited to, the trajectory of light within a spectrometer apparatus. The optical path of light within a spectrometer apparatus may be affected by reflection, refraction, dispersion, and / or absorption in one or more optical elements constituting the spectrometer apparatus, such as lenses, prisms, mirrors, diffraction gratings, etc. The terms “first” and “second” as commonly used herein are not intended to indicate ranking or numbering, but are merely for nominal convenience.

[0067] As used herein, the term “first optical path” is a broad term, given its ordinary meaning as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. Specifically, the term may, but is not limited to, an optical path that does not interact with an object. In particular, the detector signal obtained through the first optical path may not be affected by the presence and / or absence of an object in the spectrometer. For example, the detector signal obtained through the first optical path with an object applied to the spectrometer may be equal to the detector signal obtained through the first optical path without an object applied to the spectrometer (especially assuming constant environmental conditions). In particular, the first optical path may be configured to allow at least a portion of the primary or illumination light emitted from a light source to propagate from the light source to a broadband detector without interacting with an object, where the object is received, for example, by an object interface in the spectrometer. The detection light in the first optical path does not need to be reflected by an object. Through the first optical path, light emitted from a light source may be transmitted from the light source to a broadband detector without interacting with an object. The first optical path may be entirely located within the spectrometer apparatus, such as inside the housing of the spectrometer apparatus. The light traveling along the first optical path is emitted from a light source and is guided directly or indirectly to the broadband detector through reflection, refraction, dispersion, etc. For example, the first optical path may include a fiber-coupled optical path that transmits primary light or illumination light from the light source to the broadband detector. The broadband detector may be configured to generate at least one detector signal, specifically a primary detector signal, in response to illumination by incident detection light passing through the first optical path.

[0068] The first optical path may be configured to allow a portion of the primary light to propagate to the broadband detector without passing through the light-emitting material. Alternatively, or additionally, the first optical path may be configured to allow a portion of the illumination light to propagate from the light source to the broadband detector without interacting with the object. As described above, the illumination light may, at least partially, include primary light and secondary light, and specifically secondary light and primary light that is not converted to secondary light by the light-emitting material. The first optical path may include at least one optical element configured to guide a portion of the primary light or illumination light from the light source to the broadband detector without interacting with the object. The optical element may include at least one optical element selected from the group consisting of beam splitters, dichroic filters, bandpass filters, long-pass filters, short-pass filters, dispersion elements such as prisms, and diffraction elements such as diffraction gratings.

[0069] For example, the first optical path includes at least one optical element positioned between the LED and the light-emitting material, configured such that a portion of the primary light is not converted into secondary light by the light-emitting material, and this portion of the primary light is directed to a broadband detector for detecting detection light, particularly detection light including a portion of the primary light. The other portion of the primary light is converted into secondary light by the light-emitting material and directed through the second optical path to illuminate an object. In this example, the first optical path can be configured to isolate a portion of the pump light so that it does not pass through the light-emitting material, but instead passes, for example, through the LED housing to directly illuminate the broadband detector, particularly without interaction with the object.

[0070] For example, alternatively or additionally, the first optical path includes at least one optical element positioned in the optical path between the light source and the object, thereby directing a portion of the illumination light (specifically, the secondary light and the portion of the primary light not converted to secondary light by the phosphor material) to a broadband detector for detecting the detection light. The other portion of the illumination light is directed via the second optical path to illuminate the object. In this example, as described above, different optical time constants of the pump LED and the light-emitting material are used to distinguish between the primary and secondary detector signals depending on the illumination by primary and secondary light. Specifically, since pump LEDs are generally much faster than light-emitting materials, pulse trains can be used, in which case the individual pulses from the pump LED have a much higher frequency than the pulse package itself. Therefore, the primary and secondary signals can be separated by analyzing the detector signal in terms of different frequency components using a fast Fourier transform or the like.

[0071] As used herein, the term “second optical path” is a broad term, given to the meanings commonly understood and customary by those skilled in the art, and is not limited to any special or customized meaning. Specifically, the term may, but is not limited to, an optical path involving interaction with an object. In particular, the presence or absence of an object applied to the spectrometer can affect the detector signal obtained through the second optical path. For example, the detector signal obtained through the second optical path with an object applied to the spectrometer may differ from the detector signal obtained through the second optical path without an object applied to the spectrometer, and this difference can occur even under constant environmental conditions. Specifically, the second optical path may be configured to allow illumination light emitted from a light source to propagate to a broadband detector, interacting with the object at least once via the object interface of the spectrometer to which the object is applied. Specifically, the second optical path may allow at least a portion of the illumination light emitted from the light source to propagate to the object and then to the broadband detector. Illumination light emitted from a light source is directed to the object and then to the broadband detector via a second optical path, either directly or indirectly through reflection, refraction, dispersion, etc. The second optical path may be partially located outside the spectrometer, for example, outside the housing of the spectrometer. Specifically, the illumination light in the second optical path may be emitted at the object interface from the spectrometer, particularly the housing of the spectrometer, to illuminate an object located outside the spectrometer. The second optical path may be configured to recombine the detection light reflected from the object back into the spectrometer. The detection light reflected from the object may be directed directly or indirectly to the broadband detector by reflection, refraction, and / or dispersion, etc. The reflection from the object may include diffuse reflection in particular. Specifically, the detection light illuminating the broadband detector in the second optical path may be diffusely reflected light. The broadband detector may be configured to generate at least one detector signal, specifically a secondary detector signal, in response to illumination by the detection light incident through the second optical path.

[0072] For example, a broadband detector may be configured to generate a primary detector signal when it detects light in the first optical path. The broadband detector may also be configured to generate a secondary detector signal when it detects light in the second optical path. The evaluation unit may be configured to determine the broadband detector's responsiveness information from the primary detector signal and the object's spectral information from the secondary detector signal, taking into account the broadband detector's responsiveness information determined from the primary detector signal.

[0073] As used herein, the term “consider” or its grammatical variations thereof is a broad term, given its ordinary meaning as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. Specifically, the term may represent a process of modifying at least one second information item using at least one first information item, and in particular, a process of determining at least one second information item by considering at least one type of influence, such as temperature, correction coefficients, and / or calibration coefficients, represented by at least one first information item, to the at least one second information item.

[0074] For example, the responsiveness information may include at least one calibration information item. Specifically, the responsiveness information may include at least one first calibration information item, for example, a calibration information item relating to open port measurement. The first calibration information item may depend on the primary detector signal. Specifically, the first calibration information item may be given by: S_open,path2=a*S_path1,

[0075] Here, S_open,path2 represents the secondary detector signal of the second optical path in open-port measurement, S_path1 represents the primary detector signal of the first optical path, and a is a coefficient (a∈R). The relationship between the first calibration information item and the primary detector signal (e.g., coefficient a) can be determined during the factory calibration of the spectrometer, for example, by measuring the primary and secondary detector signals in the first and second optical paths, respectively, without applying a sample to the spectrometer. To obtain spectral information about the sample, the evaluation unit may be configured to determine the first calibration information item from the primary detector signal.

[0076] Furthermore, the responsiveness information may include at least one second calibration information item, for example, a calibration information item relating to a reference target measurement. The second calibration information item may depend on the primary detector signal. For example, the second calibration information item may be given by: S_(ref,path2)=b*S_path1,

[0077] Here, S_(ref,path2) represents the secondary detector signal in the second optical path having a reference target, S_path1 represents the primary detector signal in the first optical path, and b is a coefficient, b∈R. The relationship between the second calibration information item and the main detector signal, for example the coefficient b, can be determined during the factory calibration of the spectrometer, for example, by applying a reference target as the subject to the spectrometer and measuring the primary and secondary detector signals in the first and second optical paths, respectively. To obtain spectral information of the object, the evaluation unit may be configured to determine the second calibration information from the main detector signal.

[0078] Furthermore, in this example, the spectral information about the object is specifically the optical reflectance R_sample of the object, and is generally given as follows: R_Sample=(S_path2-S_(open,path2)) / (S_(ref,path2)-S_(open,path2) )

[0079] Here, S_path2 represents the secondary detector signal in the second optical path when the sample is applied to the spectrometer. The evaluation unit may further be configured to determine spectral information about the sample, specifically the optical reflectance of the sample, from the secondary detector signal, taking into account broadband detector response information, specifically first and second calibration information, determined from the primary detector signal. The first and second calibration information is wavelength-independent, at least in the spectral range of the primary and secondary light. The evaluation unit may be configured to determine the optical reflectance of the object according to the following formula: R_Sample = (S_path2 - a*S_path1) / ((b - c)*S_path1)

[0080] The spectral information (optical reflectance) in this example may therefore be spectral information corrected for fluctuating environmental conditions and / or operating conditions such as changes in detector temperature, and / or spectral information calibrated against a known reference target.

[0081] As an example, a broadband detector, as described elsewhere herein, can be used to simultaneously detect primary and secondary detector signals, which can then be used for the purposes described above. In another example, the broadband detector may include multiple detector elements, at least one specific detector element configured to determine responsiveness information on the broadband detector, and at least one further detector element configured to derive spectral information about the object. However, further examples are also conceivable.

[0082] Spectroscopic information about an object may include at least one of volumetric spectroscopic information and surface spectroscopic information about the object. Specifically, the penetration depth of illumination light into the object may depend on the spectral range of the object itself and / or the primary or secondary light used to derive the spectroscopic information. For example, the object analyzed by the spectrometer may include the user's skin. In this example, the evaluation unit may be configured to evaluate the primary detector signal generated by a broadband detector and derive volumetric spectroscopic information about the object.

[0083] It is also possible to generate primary and secondary detector signals using multiple detector elements; for example, at least one detector element containing Si can be used for wavelengths around 940 nm, and at least one additional detector element containing PbS can be used for wavelengths between 1500 and 2500 nm. Alternatively, a single broadband detector, specifically a single broadband detector containing PbS, can be used to detect light in both wavelength ranges. As yet another alternative, a Si photodiode can be used as a single broadband detector, which is specifically used to detect primary light around 440 nm and secondary light around 1100 nm. Since the excitation LED (pump LED) can be faster than the light-emitting material, by adjusting the pulse shape applied to the excitation LED, the frequency-domain information obtained from the fast Fourier transform can be made to provide spectral information from both the primary and secondary detector signals using a single broadband detector.

[0084] The spectrometer apparatus may further include at least one wavelength-selective element. The term “wavelength-selective element” as used herein is a broad term, given in the ordinary sense as commonly understood by those skilled in the art, and is not limited to any special or customized meaning. Specifically, it may, for example, represent any optical element that interacts with different spectral regions of incident light in different ways by having at least one wavelength-dependent optical property. This wavelength-dependent optical property includes at least one selected from the list consisting of reflectance, reflection direction, refractive index, refraction direction, absorptance, transmittance, and refractive index.

[0085] Wavelength selection by at least one wavelength-selecting element may be performed in at least one beampath of illumination light to select and / or change the illumination wavelength of an object, and / or in the detection beampath of detection light to select and / or change the detection wavelength, which can be done, for example, for a general broadband detector and / or each detector element. The wavelength-selecting element may include at least one wavelength-selecting element located in the optical path of illumination light, or at least one wavelength-selecting element located in the optical path of detection light.

[0086] The wavelength-selective element may be selected from at least one of a tunable wavelength-selective element or a wavelength-selective element having a fixed transmission spectrum. The wavelength-selective element having a fixed transmission spectrum may include at least one filter element, specifically at least one absorption filter element, and more specifically a bandpass filter element. The tunable wavelength-selective element may include at least one tunable interferometer, specifically at least one MEMS Fabry-Perot interferometer and / or at least one MEMS Michelson interferometer.

[0087] In a further aspect of the present invention, a method for acquiring spectral information relating to at least one object is disclosed.

[0088] This method includes the following steps, which may be performed in a predetermined order. However, a different order is also possible. In particular, one, more, or all method steps may be performed once or repeatedly. Furthermore, the method steps may be performed sequentially, or one or more method steps may be performed in overlapping or parallel manner, and / or in combination. This method may include additional steps not described.

[0089] This method includes the following steps: a) Providing at least one spectrometer apparatus according to the present invention, for example, according to any embodiment disclosed above and / or according to any embodiment disclosed in more detail below; b) A step of illuminating an object with illumination light generated by a light source, wherein 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; c) A step of detecting detection light, specifically detection light from an object and / or detection light guided from a light source to a broadband detector without interaction with the object, using at least one broadband detector, in a spectral range that at least partially includes the spectral range of primary light and the spectral range of secondary light, wherein the broadband detector is configured to generate at least one primary detector signal when it detects detection light within the spectral range of primary light, and is configured to generate at least one secondary detector signal when it detects detection light within the spectral range of secondary light; and d) A step of evaluating a primary detector signal and a secondary detector signal generated by a broadband detector using an evaluation unit, wherein the responsiveness information of the broadband detector is determined from either the primary detector signal or the secondary detector signal, and spectral information of the object is derived from the other of the primary detector signal or the secondary detector signal, taking into consideration the responsiveness information of the broadband detector.

[0090] Specifically, this method may include, for example, the use of a spectrometer apparatus according to the present invention, in any of the embodiments described above and / or in any of the detailed embodiments described later. Accordingly, for embodiments of the spectrometer apparatus and / or definitions of terms, refer to the description of the spectrometer apparatus outlined above.

[0091] Step d) may include determining the spectral information of the object in the secondary detector signal from the primary detector signal, taking into account the response information of the broadband detector determined from the primary detector signal. The spectrometer device may, in particular, be configured to have a first optical path and a second optical path as described above. The spectral information of the object may specifically include at least one of volume spectral information and surface spectral information of the object.

[0092] The spectrometer apparatus may further include at least one drive unit for electrically driving a light source. This method may, in particular in step b), include driving the light-emitting diode with the drive unit at at least one drive frequency. The drive frequency may be higher than the reciprocal of the time constant τ of the light-emitting material. The evaluation in step d) may include distinguishing between the primary detector signal and the secondary detector signal using a Fourier transform, in particular the fast Fourier transform.

[0093] Additionally, or alternatively, this method may include using a pulse train with a high frequency for the individual pulses generated by the light-emitting diode, particularly in step b), but using a pulse train with a lower frequency for the pulse package applied to the light-emitting material. The distinction between primary and secondary detector signals may include frequency multiplexing of a composite detector signal generated by a single broadband detector, particularly in step c), which may include both primary and secondary detector signals.

[0094] This method may be performed at least partially by computer, specifically at least step d). With respect to computer embodiments of the present invention, one or more method steps, or all of the method steps, of one or more embodiments of the method disclosed herein may be performed, assisted, or aided by the use of a computer or computer network. Thus, generally, any method step involving the provision and / or manipulation of data may be performed using a computer or computer network. Generally, these method steps may include any method step except for method steps that require manual work, such as providing a spectrometer and / or providing an object and / or performing the actual measurement.

[0095] In a further aspect of the present invention, a computer program is disclosed which, when executed by a spectrometer apparatus according to the present invention, for example, according to any of the embodiments described above and / or any of the more detailed embodiments described below, causes the spectrometer apparatus to perform at least steps b) to d) of the method according to the present invention, for example, according to any one of the embodiments disclosed above and / or any one of the embodiments disclosed in further detail below.

[0096] In a further aspect of the present invention, a computer-readable storage medium, particularly a non-temporary computer-readable medium, is disclosed. This medium causes the spectrometer to perform, for example, one of the embodiments disclosed above and / or one of the embodiments disclosed in further detail below, when a command is executed by the spectrometer according to the present invention.

[0097] In this specification, the term “computer-readable storage medium” may, in particular, refer to non-temporary data storage means, such as a hardware storage medium on which computer-executable instructions are stored. The computer-readable storage medium may, in particular, be a storage medium such as random access memory (RAM) and / or read-only memory (ROM), or may include such media.

[0098] The spectrometer apparatus and method according to the present invention offer numerous advantages over similar known apparatuses and methods in one or more embodiments described above and / or in one or more embodiments described in more detail below. A spectrometer apparatus equipped with a broadband detector offers the possibility of using both primary and secondary light to determine responsiveness information in the broadband detector, and further offers the possibility of deriving spectral information about an object by selecting and / or extending the spectral emission range, in particular, using an excitation LED having a shorter emission wavelength and a light-emitting material having an emission spectrum in a longer wavelength range, taking the responsiveness information into consideration. In this way, the spectral information of the object can be corrected and / or compensated for the temperature drift of the broadband detector.

[0099] The spectrometer apparatus and method according to the present invention can particularly utilize the fact that a portion of the excitation light passes through the light-emitting material without being converted into secondary light, and this generally belongs to a wavelength region different from that of the secondary light. By using an optical system, specifically a first and second optical path, and using one or more dispersive elements such as a beam splitter, dichroic filter, bandpass filter, long-pass filter, short-pass filter, prism, diffraction elements such as a diffraction grating, the pump light can be guided to a broadband detector without passing through the interface with the object and therefore without interacting with the object. The secondary light can interact with the object. Therefore, the secondary light incident on the broadband detector retains information about the object and can be used to determine the spectral information of the object. Since the primary light does not retain object information, it can be used as a reference signal. By determining the drift of the broadband detector in the secondary detector signal with respect to the primary detector signal generated by the pump light, the secondary detector signal caused by the secondary light can be corrected. Furthermore, the temperature drift of the broadband detector can be compensated using the primary detector signal as a reference.

[0100] To detect radiation in both wavelength ranges, the spectrometer is equipped with a broadband detector, which is specifically embodied by multiple individual detector elements or a single broadband detector that are sensitive to both the primary and secondary light wavelength ranges, particularly the excitation wavelength range of the LED and the conversion wavelength range of the light-emitting material. When detecting both radiations using a single broadband detector, the primary and secondary detector signals can be distinguished by pulse width modulation of the light source.

[0101] In a particularly preferred embodiment, the LED for the pump can be modulated using a pulse train, and specifically using a drive unit described herein. The term “pulse train” as used herein is a broad term and is given the meaning that is ordinarily understood by those skilled in the art, and is not limited to any special or customized meaning. Specifically, the term may refer to a continuous pulse train in which the individual pulses have a high frequency, but the pulse package as a whole has a lower frequency, and is used in particular to generate excitation of at least one material irradiated by the pulse train. In other words, the high-frequency train of individual pulses is modulated by the lower frequency of the pulse package, which can be represented by a modulation frequency f1. To provide additional information regarding the modulation frequency f1, typically, the decay that occurs between the absorption of at least one primary photon by the light-emitting material and the emission of at least one secondary photon by the light-emitting material can be taken into account. This delay may be characterized by a so-called “characteristic time constant” τ (also called the time constant, decay time, or saturation time). As is generally known to those skilled in the art, the term “time constant” as used herein is a broad term, given its ordinary meaning based on the ordinary technical knowledge of those skilled in the art, and is not limited to any special or specific meaning. When used in processes where the rate or probability of a process, such as photon emission, is proportional to one or more states or the occupancy rate of process states, the occupancy rate usually changes exponentially. The time constant τ in these processes may also determine the 1 / e time of the process. In light-emitting materials or converters, particularly phosphors, two different time constants may arise. Firstly, the first time constant may describe a typical time to reach saturation of the emission of the converted light. Secondly, the second time constant may describe a typical time for the afterglow of the light-emitting material or converter.

[0102] The typical time constant of a phosphor converter is in the range of 0.1 ms to less than 10 ms. The time constant usually differs between different phosphor LEDs and / or between different types of light-emitting materials (phosphors). Generally, phosphors that emit shorter wavelengths exhibit smaller time constants. Furthermore, the decay time constant τ... d and the light-enhancing time constant τ gThese time constants may be wavelength-dependent. These time constants are typically derived from the step response of the optical signal upon application or interruption of forward current, respectively.

[0103] After the forward current is interrupted, the signal or light emission typically decays according to equation (1): S(t)=S max e^(-(t-t0) / τ d ) + S0. (1) After applying a forward current, the signal or light emission typically increases according to equation (2): S(t)=S max (1-e^(-(t-t0) / τ g ) ) + S0. (2)

[0104] In both equations (1) and (2), S0 is the optical signal level at time t0 when the forward current is applied / cut off. Smax is the optical signal level reached at t≫5.

[0105] In particular, the increasing time constant τ g and decay time constant τ d By using this, the modulation frequency f1 can be expressed in equation (3) as follows:

[0106] f1≫1 / (max(τ g ,τ d )) (3)

[0107] An embodiment of a pulse train is described and illustrated below.

[0108] In particular with respect to the present invention, this pulse train makes it possible to simultaneously provide primary light with high frequencies of individual pulses generated by the pump LED and secondary light with a low modulation frequency f1 of the pulse package. Here, the low modulation frequency f1 of the pulse package is selected so that the light-emitting material or converter, specifically a phosphor, can follow the excitation by the pulse package provided by the pulse train. When a single broadband detector is used to detect both emissions, frequency multiplexing of the combined detector signal generated by the single broadband detector makes it possible to distinguish between the primary detector signal (i.e., the pump signal provided by the LED) and the secondary detector signal (i.e., the converter signal provided by the light-emitting material, specifically a phosphor) within the combined detector signal generated by the single broadband detector. In this way, different types of information can be extracted from the combined detector signal generated by the single broadband detector and then used for the purpose of the present invention, namely determining the responsiveness information of the broadband detector and deriving the spectral information of the object, taking into account the responsiveness information of the broadband detector.

[0109] In this specification, the terms “have,” “include,” or “encompass,” and any grammatical variations thereof, are used in a non-exclusive sense. Therefore, these terms can represent both situations where the entity described in this context has no further features other than those introduced by the term, and situations where one or more further features exist. For example, the expressions “A has B,” “A includes B,” and “A encompasses B” may represent both situations where there are no elements other than B (i.e., A consists only of B), and situations where A has elements C, C and D, or more elements in addition to B.

[0110] Furthermore, it should be noted that phrases like "at least one," "one or more," or similar expressions (primarily indicating that a feature or element may exist one or more times) are usually used only once when introducing that feature or element. In most cases, when referring to that feature or element, the phrases "at least one" or "one or more" are not repeated, even if that feature or element may exist one or more times.

[0111] Furthermore, in this specification, the terms “preferably,” “more preferably,” “particularly,” “more especially,” “specifically,” “more specifically,” or similar terms are used in combination with any feature without limiting substitutability. Accordingly, 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 present invention may be carried out using alternative features. Similarly, features introduced by “in embodiments of the present invention” or similar expressions are intended to be optional features, without any limitation on alternative embodiments of the present invention, without any limitation on the scope of the invention, and without any limitation on the possibility of combining such introduced features with other optional or non-optional features of the present invention.

[0112] In summary, without precluding further possible embodiments, the following embodiments are envisioned:

[0113] "Embodiment 1" A spectrometer device for acquiring spectral information about at least one object, comprising the following configuration: i. At least one light source that generates illumination light for illuminating an 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; ii. At least one broadband detector for detecting detection light, specifically detection light from an object and / or a light source, which is guided to the broadband detector without interaction with the object, in a spectral range that at least partially includes the spectral ranges of primary and secondary light, wherein the broadband detector is configured to generate at least one primary detector signal when it detects detection light within the spectral range of primary light, and further configured to generate at least one secondary detector signal when it detects detection light within the spectral range of secondary light; iii. At least one evaluation unit for evaluating the primary and secondary detector signals generated by a broadband detector, determining the responsiveness information of the broadband detector from either the primary or secondary detector signal, and deriving spectral information of the object from the other of the primary or secondary detector signal, taking into account the responsiveness information of the broadband detector. A spectrometer device, including a spectrometer.

[0114] Embodiment 2 Furthermore, the following: iv. At least one first optical path configured to allow a portion of the primary light or illumination light to propagate from the light source to a broadband detector without interacting with the object; v. At least one second optical path, configured to allow illumination light to propagate from a light source to a broadband detector, interacting with the object at least once along the way. A spectrometer apparatus according to Embodiment 1, including the above.

[0115] "Embodiment 3" The spectrometer apparatus according to Embodiment 2, wherein the first optical path is configured to allow a portion of the primary light to propagate to a broadband detector without passing through the light-emitting material.

[0116] Embodiment 4 The spectrometer apparatus according to Embodiment 2 or 3, wherein the first optical path is configured to allow a portion of the illumination light to propagate from the light source to the broadband detector without interacting with the object, and the illumination light comprises at least partially primary and secondary light.

[0117] Embodiment 5 The spectrometer apparatus according to any one of embodiments 2 to 4, wherein the first optical path includes at least one optical element configured to guide at least a portion of the primary light or illumination light from a light source to a broadband detector without interacting with the object.

[0118] Embodiment 6 The spectrometer apparatus according to Embodiment 5, wherein the optical element includes at least one optical element selected from the group consisting of a beam splitter, a dichroic filter, a bandpass filter, a longpass filter, a shortpass filter, a dispersion element such as a prism, and a diffraction element such as a grating.

[0119] Embodiment 7 A spectrometer apparatus according to any one of embodiments 2 to 6, wherein a broadband detector is configured to generate a primary detector signal by detecting detection light in a first optical path, and the broadband detector is configured to generate a secondary detector signal by detecting detection light in a second optical path.

[0120] Embodiment 8 The spectrometer apparatus according to Embodiment 7, wherein the evaluation unit is configured to determine the response information of the broadband detector from the primary detector signal, taking into account the response information of the broadband detector determined from the primary detector signal, and to determine the spectral information of the object from the secondary detector signal.

[0121] Embodiment 9 A spectrometer apparatus according to any one of Embodiments 1 to 8, wherein the broadband detector is configured to detect detection light in a spectral range of 200 nm to 5 μm, preferably 300 nm to 3 μm, and more preferably 400 nm to 2.5 μm.

[0122] Embodiment 10 A spectrometer apparatus according to any one of Embodiments 1 to 9, wherein the broadband detector includes a plurality of detector elements for detecting detected light in the spectral range of primary and secondary light.

[0123] Embodiment 11 The spectrometer apparatus according to Embodiment 10, wherein each detector element includes a photosensitive material selected from at least one of PbS, PbSe, InSb, or HgCdTe.

[0124] Embodiment 12 The spectrometer apparatus according to Embodiment 10 or 11, wherein each detector element includes a photodiode comprising at least one of Si, Ge, InGaAs, or ext. InGaAs.

[0125] Embodiment 13 A spectrometer apparatus according to any one of embodiments 1 to 12, wherein the broadband detector is a single detector comprising a photosensitive material selected from at least one of PbS, PbSe, InSb, or HgCdTe.

[0126] Embodiment 14 A spectrometer apparatus according to any one of embodiments 1 to 13, wherein the broadband detector is a single detector comprising a photodiode, particularly a photodiode comprising at least one of Si, Ge, InGaAs, or extended InGaAs.

[0127] Embodiment 15 The spectrometer apparatus according to embodiment 13 or 14, further comprising at least one drive unit for electrically driving a light source, the drive unit being configured to drive a light-emitting diode at at least one drive frequency, the drive frequency being greater than the reciprocal of the time constant τ of the light-emitting material.

[0128] Embodiment 16 The spectrometer apparatus according to Embodiment 15, wherein the evaluation unit is configured to distinguish between a primary detector signal and a secondary detector signal using a Fourier transform, particularly a fast Fourier transform.

[0129] Embodiment 17 A spectrometer apparatus according to any one of Embodiments 1 to 16, wherein the illumination light includes the portion of primary light generated by a light-emitting diode that is not converted into secondary light by a light-emitting material and the secondary light.

[0130] Embodiment 18 A spectrometer apparatus according to any one of Embodiments 1 to 17, wherein the primary light is located at least partially 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 even more specifically in the spectral range of 440 nm to 830 nm.

[0131] Embodiment 19 The spectrometer apparatus according to Embodiment 18, wherein primary light that is not converted into secondary light by the light-emitting material is present at least partially 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 even more specifically in the spectral range of 440 nm to 830 nm.

[0132] Embodiment 20 A spectrometer apparatus according to any one of Embodiments 1 to 19, wherein the secondary light is located at least partially in a spectral range of 1 μm to 5 μm, specifically in a spectral range of 1.5 μm to 3 μm, and more specifically in a spectral range of 1.5 μm to 2.5 μm.

[0133] Embodiment 21 A spectrometer apparatus according to any one of Embodiments 1 to 20, wherein the light source includes a phosphor light-emitting diode.

[0134] Embodiment 22 A spectrometer apparatus according to any one of embodiments 1 to 21, wherein the spectrometer apparatus further includes at least one wavelength-selective element.

[0135] Embodiment 23 The spectrometer apparatus according to Embodiment 22, wherein the wavelength-selective element includes at least one of a wavelength-selective element arranged in the optical path of illumination light or a wavelength-selective element arranged in the optical path of detection light.

[0136] Embodiment 24 The spectrometer apparatus according to embodiment 22 or 23, wherein the wavelength-selective element is selected from at least one of a wavelength-tunable wavelength-selective element or a wavelength-selective element having a fixed transmission spectrum.

[0137] Embodiment 25 The spectrometer apparatus according to Embodiment 24, wherein the wavelength-selective element having a fixed transmission spectrum includes at least one filter element, more specifically at least one absorption filter element, and more specifically a bandpass filter element.

[0138] Embodiment 26 The spectrometer apparatus according to Embodiment 24 or 25, wherein the wavelength-tunable wavelength-selective element includes at least one wavelength-tunable interferometer, specifically at least one MEMS Fabry-Perot interferometer and / or at least one MEMS Michelson interferometer.

[0139] Embodiment 27 A method for obtaining spectral information about at least one object, comprising the following steps: a) Providing at least one spectrometer apparatus according to any one embodiment described in any one of embodiments 1 to 16; b) A step of illuminating an object with illumination light generated by a light source, wherein 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; c) A step of detecting detection light, specifically detection light from an object and / or detection light guided from a light source to a broadband detector without interaction with an object, using at least one broadband detector, in a spectral range that at least partially includes the spectral range of primary light and the spectral range of secondary light, wherein the broadband detector is configured to generate at least one primary detector signal when it detects detection light within the spectral range of primary light, and is configured to generate at least one secondary detector signal when it detects detection light within the spectral range of secondary light; and d) Using an evaluation unit, evaluate the primary and secondary detector signals generated by the broadband detector, determine the responsiveness information of the broadband detector from either the primary or secondary detector signal, and derive the spectral information of the object from the other of the primary or secondary detector signal, taking into account the responsiveness information of the broadband detector. A method that includes this.

[0140] Embodiment 28 The method according to Embodiment 27, wherein step d) includes determining the broadband detector response information determined from the primary detector signal and the spectral information of the object determined from the secondary detector signal, taking into account the broadband detector response information determined from the primary detector signal.

[0141] Embodiment 29 The spectrometer apparatus further comprises at least one drive unit for electrically driving a light source, and the method, in particular in step b), includes using the drive unit to drive a light-emitting diode at at least one drive frequency, the drive frequency being higher than the reciprocal of the time constant τ of the light-emitting material, according to Embodiment 27 or 28.

[0142] "Embodiment 30" The method according to Embodiment 29, wherein the evaluation in step d) includes distinguishing between the primary detector signal and the secondary detector signal using a Fourier transform, particularly the fast Fourier transform.

[0143] Embodiment 31 The method according to any one of embodiments 27 to 30, specifically comprising, in step b), using a pulse train having a high frequency for the individual pulses generated by the light-emitting diode, but using a pulse train having a lower frequency for the pulse package applied to the light-emitting material.

[0144] Embodiment 32 The method according to Embodiment 31, wherein the distinction between the primary detector signal and the secondary detector signal is, in particular in step c), frequency multiplexing of a composite detector signal generated by a single broadband detector, and the composite detector signal includes both the primary detector signal and the secondary detector signal.

[0145] "Embodiment 33" A method according to any one of embodiments 27 to 32, which is at least partially carried out by a computer, and specifically involves at least step d).

[0146] Embodiment 34 A computer program that, when the program is executed by a spectrometer apparatus described in any one of embodiments 1 to 26 relating to a spectrometer apparatus, includes instructions causing the spectrometer apparatus to perform steps b) to d) of the embodiment described in any one of embodiments 27 to 33 relating to a spectrometer apparatus.

[0147] Embodiment 35 A computer-readable storage medium, specifically a non-temporary computer-readable medium, wherein when a command is executed by a spectrometer apparatus as described in embodiments 1 to 26 relating to a spectrometer apparatus, the command causes the method to perform at least steps b) to d) according to any one of embodiments 27 to 33 relating to the method. [Brief explanation of the drawing]

[0148] Further optional features and embodiments are disclosed in more detail in conjunction with the following descriptions of embodiments, preferably dependent claims, where each optional feature can be realized individually or in any feasible combination, as will be understood by those skilled in the art. The scope of the present invention is not limited by preferred embodiments. Embodiments are schematically shown in the drawings. In the drawings, the same reference numerals indicate the same or functionally equivalent elements. [Figure 1] Figure 1 is a schematic diagram showing an example of a spectrometer apparatus. [Figure 2] Figure 2 shows a schematic cross-sectional view of an embodiment of the light source. [Figure 3] Figure 3 is a flowchart illustrating an embodiment of a method for acquiring spectral information about at least one object. [Figure 4] Figure 4 shows the spectral sensitivity characteristics of the broadband detector. [Figure 5] Figure 5 shows a diagram of pulse width modulation. [Modes for carrying out the invention]

[0149] Figure 1 shows a schematic diagram of a spectrometer apparatus 110 for acquiring spectral information about at least one object 112. The spectrometer apparatus 110 may include multiple components as shown in Figure 1. The possible components of the spectrometer apparatus 110 and their interactions will be described in detail below with reference to Figure 1. The spectrometer apparatus 110 includes at least one light source 114 that generates illumination light 116 for illuminating the 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. In particular, the light source 114 may be at least one electric light source, 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 optically converting the primary light generated by the light-emitting diode 118 into secondary light. For example, the light-emitting diode 118 may include one or more of the following: a light-emitting diode (LED) based on spontaneous emission, a light-emitting diode (sLED) based on superluminescence, or a laser diode (LLED).

[0150] The LED 118 may, in particular, include at least two semiconductor material layers 121, and may be configured such that light is generated at at least one interface between the at least two semiconductor material layers 121, particularly by 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 layer being an n-type doped semiconductor material 121 and at least one layer being a p-type doped semiconductor material 121. Thus, as an example, the LED 118 may include at least one pn junction and / or at least one pin configuration. However, it should be noted that other device structures are also possible.

[0151] The light-emitting diode 118 can generate primary light (also called "pump light"). This primary light can then be converted into "secondary light" using, for example, photoconversion via one or more light-emitting materials 120 such as phosphor materials. Therefore, at least one light-emitting material 120 can form at least one converter, also called a photoconverter, which converts primary light into secondary light having different spectral characteristics from the primary light. Specifically, the spectral width of the secondary light may be wider than that of the primary light, and / or the center wavelength of the secondary light may be shifted (particularly redshifted) compared to the primary light. Specifically, at least one light-emitting material 120 may absorb in the ultraviolet and / or blue spectral region and emit light in the near-infrared and / or infrared spectral region. The illumination light 116 may also include, at least partially, primary light and secondary light. Specifically, the illumination light 116 may include the portion of the primary light generated by the light-emitting diode 118 that was not converted into secondary light due to reasons such as low conversion efficiency by the light-emitting materials 120, and the secondary light.

[0152] As shown in Figure 1, the light source 114 may specifically include a phosphor light-emitting diode 122, also known as a phosphor LED 122. The phosphor LED 122 may combine at least one light-emitting diode 118 configured to generate primary light or excitation light, and at least one light-emitting material 120 (also called a "phosphor") configured to convert the primary light generated by the light-emitting diode 118 into light. The phosphor LED 122 may form a packaged LED light source, which includes an LED die 124, such as a blue LED that emits blue pump light, and a phosphor, for example, the phosphor completely or partially covering the LED 118, and the LED 118 is configured to convert, for example, the primary light or blue light into light with different spectral characteristics, specifically near-infrared light. Figure 2 shows a detailed view of the light source 114 as specified as a phosphor LED 122.

[0153] In general, the light source 114 can be implemented in various ways. Therefore, the light source 114 may be positioned as part of the spectrometer apparatus 110 within the housing 126 of the spectrometer apparatus 110, for example, as shown in Figure 1. However, alternatively or additionally, at least one light source 114 may be positioned outside the housing 126, for example, as a separate light source 114 (not shown). The light source 114 may be positioned separately from the object 112, as shown in Figure 1, and may illuminate the object 112 from a distance. This allows the light-emitting diode 118 and the light-emitting material 120 to be thermally coupled, generally as indicated by reference numeral 127. In other words, during operation of the light source 114, a temperature difference of 0.1K to 5K, particularly 0.1K to 1K, and more specifically 0.1K to 0.5K may occur between the light-emitting diode 118 and the light-emitting material 1120. As a result, a single temperature can be assigned to both the light-emitting diode 118 and the light-emitting material 120 contained in the light source 114 at a given power spectral density of primary and secondary light.

[0154] The illumination light 116 generated by the light source 114 may propagate from the light source 114 to the object 112. In Figure 1, the illumination light 116 generated by the light source 114 and propagating to the object 112 is indicated by an arrow. The object 112 may include, in particular, at least one sample that is analyzed completely or partially by spectroscopy.

[0155] As shown in Figure 1, the spectrometer apparatus 110 may further include at least one first optical path 123 and at least one second optical path 125. The first optical path 123 may be configured to allow at least a portion of the primary light or illumination light 116 to propagate from the light source 114 to the broadband detector 128 without interacting with the object 112. The second optical path 125 may be configured to allow the illumination light 116 to propagate from the light source 114 to the broadband detector 128, interacting with the object 112 at least once. Furthermore, the first optical path 123 may be configured to allow a portion of the primary light to propagate to the broadband detector 128 without passing through the light-emitting material 120. Alternatively, or additionally, the first optical path 123 may be configured to allow a portion of the illumination light 116 to propagate from the light source 114 to the broadband detector 128 without interacting with the object 112. As described above, the illumination light 116 may, at least partially, include primary light and secondary light, specifically secondary light and primary light that is not converted to secondary light by the light-emitting material 120. The first optical path 123 may include at least one optical element (not shown in Figure 1) configured to guide at least a portion of the primary light from the light source 114 or the illumination light 116 to the broadband detector 128 without interacting with the object 128. This optical element may also include at least one optical element selected from the group consisting of beam splitters, dichroic filters, bandpass filters, long-pass filters, short-pass filters, dispersion elements such as prisms, and diffraction elements such as diffraction gratings.

[0156] As is clear from Figure 1, the spectrometer apparatus 110 further includes at least one broadband detector 128 configured to detect detection light 130, specifically detection light 130 from the object 112 and / or detection light 130 guided from the light source 114 to the broadband detector 128 without interacting with the object 112, in a spectral range that at least partially includes the spectral ranges of primary and secondary light. The light propagating from the light source 114 to the object 112 may be referred to as illumination light 116, while the light propagating from the object 112 to the broadband detector 128 may be referred to as "detection light" 130. In Figure 1, the detection light 130 is indicated by an arrow. The detection light 130 may include at least one of the illumination light 116 reflected by the subject 112, the illumination light 116 scattered by the subject 112, the illumination light 116 transmitted by the subject 112, or the emitted light generated by the subject 112, such as phosphorescence or fluorescence generated by the object 112 after optical, electrical, or acoustic excitation of the object 112 by the illumination light 116, etc. Thus, the detection light 130 may be generated directly or indirectly through the illumination of the object 112 by the illumination light 116. Additionally, as shown in Figure 1, the detection light 130 may include light generated by the light source 114, specifically primary light, secondary light, and / or a combination of primary light and secondary light, which may be guided to the broadband detector 128 via the first optical path 123 without interacting with the object 112.

[0157] The broadband detector 128 is configured to generate at least one primary detector signal when it detects detection light 130 in the spectral range of primary light. The broadband detector 128 is further configured to generate at least one secondary detector signal when it detects detection light 130 in the spectral range of secondary light. For example, the broadband detector 128 may include a plurality of detector elements 132, such as an array of photosensitive elements, for detecting detection light 130 in the spectral ranges of primary and secondary light. The broadband detector 128 may include a pixelated broadband detector comprising a plurality of photosensitive pixels or elements, as described above. For example, the broadband detector 128 may include at least one first detector element 131 for detecting detection light 130 in the spectral range of primary light and at least one second detector element 133 for detecting detection light 130 in the spectral range of secondary light. Specifically, the first detector element 131 may be configured to generate a primary detector signal when it detects detection light 130 in the spectral range of primary light. The second detector element 133 may be configured to generate a secondary detector signal when it detects the detected light 130 in the spectral range of the secondary light. Each detector element 131, 133 may include a photosensitive material selected from at least one of PbS, PbSe, InSb, or HgCdTe. Alternatively, the broadband detector 128 may be a single detector 134 including a photosensitive material selected from at least one of PbS, PbSe, InSb, or HgCdTe. As yet another alternative, the broadband detector 128 may be a single detector 134 having a photodiode, in particular including a photodiode made of at least one material selected from Si, Ge, InGaAs, or ext. InGaAs. In Figure 1, reference numerals 132 and 134 are used together to indicate the arrangement of multiple detector elements 132 and a single detector 134 in the spectrometer apparatus 110, although the spectrometer apparatus 110 may have multiple detector elements 132 in one embodiment and a single detector 134 in another embodiment.

[0158] The broadband detector 128 may be configured to generate electrical signals in response to the intensity of incident light. In particular, these electrical signals may be supplied to the evaluation unit 136 of the spectrometer device 110, as will be described later.

[0159] The spectrometer apparatus 110 includes at least one evaluation unit 136 for evaluating at least one of the primary and secondary detector signals generated by the broadband detector 128, and for determining spectral information about the object 112 from at least one of the primary and secondary detector signals. The broadband detector 128 can provide the detector signal to the evaluation unit 136 directly or indirectly. Therefore, as indicated by the arrows in Figure 1, the broadband detector 128 and the evaluation unit 136 may be connected directly or indirectly. The detector signal may be used as a "raw" detector signal, or it may be processed or preprocessed before further use, for example, by filtering. Therefore, the broadband detector 128 may include at least one processing unit and / or at least one preprocessing unit (e.g., at least one of an amplifier, an analog-to-digital converter, an electrical filter, or a Fourier transform device).

[0160] As shown in Figure 1, the spectrometer apparatus 110 may further include at least one drive unit 138 for electrically driving the light source 114. The drive unit 138 may be configured to supply current to the LED 118, and specifically to control the current flowing through the LED 118. Here, as an example, the drive unit 138 may be configured to adjust and measure the voltage supplied to the LED 118, where this voltage is required to supply a specific current to the LED 118. Specifically, the drive unit 138 may include one or more current sources 140, voltage sources, current measuring devices (such as ampere meters), voltage measuring devices 142 (such as voltmeters), and power measuring devices. Specifically, the drive unit 138 may include at least one current source 140 for supplying at least one predetermined current to the LED 118, and this current source 140 is configured to adjust or control the voltage applied to the LED 118 to generate the predetermined current. The drive unit 138 may, for example, include one or more electrical components (e.g., integrated circuits) for driving the light source 114. The drive unit 138 may be fully or partially integrated with the light source 114, or it may be separated from the light source 114, the latter configuration of which is shown in Figure 1. If the broadband detector 128 is a single detector 134, the drive unit 138 may be included in the spectrometer apparatus 110 in particular. However, the spectrometer apparatus 110 may also include the drive unit 138 in other embodiments of the broadband detector 128. The drive unit 138 may be configured to drive the light-emitting diode 118 at at least one drive frequency. The drive frequency may be set to be above the reciprocal of the attenuation constant τ of the light-emitting material 120 in particular. Furthermore, the evaluation unit 136 may be configured to distinguish between the primary detector signal and the secondary detector signal using a Fourier transform, in particular the fast Fourier transform. Thus, the spectrometer apparatus 110 may be configured to perform pulse width modulation of the light source 114 using the drive unit 138. As shown in the lower part of Figure 5, pulse width modulation can be achieved using a pulse train.

[0161] As described above and as shown in Figure 1, the spectrometer apparatus 110 includes 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 deriving spectral information about the object 112 from at least one of the primary detector signal and the secondary detector signal. Specifically, the evaluation unit 136 may be configured to evaluate both the primary detector signal and the secondary detector signal generated by the broadband detector 128. The evaluation unit 136 is configured to determine the responsiveness information 137 of the broadband detector 128 from either the primary detector signal or the secondary detector signal, and to derive spectral information about the object 112 from the other of the primary detector signal or the secondary detector signal, taking into account the responsiveness information 137 of the broadband detector 128. For example, the responsiveness information 137 of the broadband detector 128 may be determined from the primary detector signal, while the spectral information of the object 112 may be derived from the secondary detector signal, taking into account the responsiveness information 137 of the broadband detector 128 determined from the primary detector signal. In this way, the spectral information relating to the object 112 can be corrected and / or compensated for the temperature drift of the broadband detector 128.

[0162] The evaluation unit 136 may be one or more integrated circuits, such as one or more application-specific integrated circuits (ASICs), and / or one or more data processing devices 144 (e.g., one or more computers, digital signal processing devices (DSPs), field-programmable gate arrays (FPGAs), preferably one or more microcomputers and / or microcontrollers), or may include them. It may also include additional components, for example, one or more preprocessing devices 146 and / or data acquisition devices, such as one or more AD converters and / or one or more filters, for receiving and / or preprocessing detector signals. Furthermore, the evaluation unit 136 may include one or more data storage devices 148, as shown in Figure 1. Furthermore, the evaluation unit 136 may include one or more interfaces, for example, one or more wireless interfaces and / or one or more wired interfaces.

[0163] The spectrometer apparatus 110 may further include one or more optical components 150, such as one or more mirrors, one or more lenses, one or more apertures, and one or more wavelength-selective elements 152. The wavelength-selective elements 152 may be arranged to generate at least one primary detector signal when the broadband detector 128 detects detection light 130 within the spectral range of primary light, and to generate at least one secondary detector signal when it detects detection light 130 within the spectral range of secondary light. As shown in Figure 1, wavelength selection by at least one wavelength-selective element 152 may also be performed in at least one optical path of illumination light 116, thereby selecting and / or changing the wavelength of illumination of the subject 112, and / or selecting and / or changing the detection wavelength in the detection optical path of detection light 130, for example, for the broadband detector 128 as a whole and / or for each detector element 131, 133. The wavelength-selective elements 152 may include at least one of wavelength-selective elements 152 located in the optical path of illumination light 116, or wavelength-selective elements 152 located in the optical path of detection light 130. The wavelength-selective element 152 may be specifically selected from at least one of a tunable wavelength-selective element or a wavelength-selective element having a fixed transmission spectrum.

[0164] The spectrometer apparatus 110, schematically shown in Figure 1, is configured to acquire spectral information relating to at least one object 112. In particular, the spectrometer apparatus 110 may be configured to acquire information items characterizing at least one optical property of the object 112, relating to at least one object 112 and / or radiation emitted from the object 112, more specifically, at least one information item characterizing, e.g. qualitatively and / or quantitatively, at least one of the transmission, absorption, reflection and emission of the object 112. As an example, the at least one spectral piece of information may include at least one intensity piece of information, for example, information relating to the intensity of light transmitted, absorbed, reflected or emitted by the object 112, for example, over one or more wavelengths, for example, as a function of wavelength or wavelength subrange over a wavelength range. Thus, the spectrometer apparatus 110 may be configured to acquire at least one spectrum, or a portion of a spectrum, of the detected light 130 propagating from the object 112 to the broadband detector 128. The spectrum can be described, for example, as a wavelength function of the detected light 130, in radiative units of the spectral flux (e.g., watts per nanometer (W / nm)) or other units. Thus, the spectrum can describe the optical power of the light in a specific wavelength band (e.g., the NIR spectral range). The spectrum may include one or more optical variables as a function of wavelength, such as power spectral density, electrical signals derived by optical measurements, etc. The spectrum may include the spectral ranges of primary and secondary light in particular. The spectrometer device 110 may be a portable spectrometer device, for example, part of a mobile device, or it may be attachable to a mobile device such as a notebook computer, tablet, mobile phone (e.g., smartphone), smartwatch, and / or wearable computer (not shown in Figure 1).

[0165] Figure 2 shows a schematic cross-sectional view of the light source 114. At least one light source 114 of the spectrometer apparatus 110 may be configured to generate or supply electromagnetic radiation in one or more of the infrared, visible light, and ultraviolet spectral ranges. Since the material properties and chemical compositional properties of many objects 112 can be derived from the near-infrared spectral region, the light used in typical applications of the present invention is light in the infrared (IR) spectral region, more preferably near-infrared (NIR) and / or mid-infrared (MidIR) spectral region, particularly light with wavelengths of 1 μm to 5 μm, preferably 1 μm to 3 μm. The light source 114 includes at least one light-emitting diode 118 and at least one light-emitting material 120 for photoconverting the primary light generated by the light-emitting diode 118. The LED 118 and phosphor 120 may constitute a phosphor LED 122 as described above.

[0166] The phosphor LED 122 shown in Figure 2 may include one or more functional components. Specifically, the phosphor LED 122 may include one or more substrates 154, in particular one or more electrically insulating substrates 154. In particular, as shown in Figure 2, the phosphor LED 122 may include one or more ceramic substrates 156. The substrate 154 may be configured to hold at least one LED die 124 and at least one light-emitting material 120. Furthermore, at least one substrate 154 may hold or include at least one electrically connectable component, such as at least one contact pad 158 and / or at least one electrical lead (e.g., at least one metal contact and / or at least one metal lead), as shown in Figure 2. The substrate 154 may be configured to function as a heat sink. Heat may be generated within the LED die 124 (e.g., due to the limited efficiency of the conversion from electrical energy to photon energy) and within the light-emitting material 120 (e.g., during the conversion process). The heat can be dissipated within the substrate 154, such as a ceramic substrate.

[0167] As shown in Figure 2, the phosphor LED 122 may include a light-emitting diode 118. The light-emitting diode 118 may be configured to convert an electrical current into primary light, such as blue primary light, using at least one LED chip and / or at least one LED die 124, as shown in Figure 2. Specifically, a pn diode may be used. As an example, one or more LEDs 118 selected from indium gallium nitride (InGaN) based LEDs 118, GaN based LEDs 118, InGaN / GaN alloy based LEDs 118, combinations thereof, and / or other LEDs 118 may be used. Additionally, or instead, quantum well LEDs 118 may also be used, for example, one or more InGaN-based quantum well LEDs 118 may be used. Additionally, or instead, superluminescent LEDs (sLEDs) and / or quantum cascade lasers may be used. As is more apparent from Figure 2, the phosphor LED may include at least one light-emitting material 120 configured to convert primary light produced by the light-emitting diode 118 into light. Various types of conversion and / or emission are known and can be used in the context of the present invention. Specifically, the luminescent material 120 may include at least one of the following: cerium-doped YAG (YAG:Ce 3+ , or Y3Al5O 12 :Ce 3+ ); Rare earth-added sialon; Copper and aluminum-added zinc sulfide (ZnS:Cu,Al).

[0168] The light-emitting material 120 can form at least one layer. In general, various alternatives for arranging the light-emitting material 120 relative to the light-emitting diode 118 can be realized individually or in combination. Firstly, at least one layer of the light-emitting material 120, such as a phosphor, can be directly arranged on the light-emitting diode 118, for example, when no material is sandwiched between the LED 118 and the phosphor material 120, or when one or more transparent materials (particularly materials transparent to primary light) are sandwiched between the LED and the phosphor material 120. Thus, as an example, a coating of the light-emitting material 120 can be arranged directly or indirectly on the LED 118 (not shown). Additionally, or instead, the light-emitting material 120 can form, for example, at least one transducer body 160 (also referred to as at least one transducer disk or transducer platelet). The transducer body 160 can be arranged on the LED 118, for example, by attaching the transducer body 160 to the LED 118 with adhesive, as shown in Figure 2. Additionally, or alternatively, the light-emitting material 120 may be remotely positioned, in which case the primary light from the LED 118 must pass through an intermediate optical path before reaching the light-emitting material 120 (not shown). For example, the light-emitting material 120 in a remote position may form a solid body such as a disk or a converter disk, or a converter body 160. One or more optical elements such as lenses, prisms, diffraction gratings, mirrors, apertures, or combinations thereof may be placed in the intermediate optical path. Specifically, an optical system with image-forming properties can be placed in the intermediate optical path between the LED 118 and the light-emitting material 120. This allows, for example, the primary light to be focused or bundled onto the converter body 160.

[0169] In a light source 114, and more specifically in a phosphor LED 122, at least one light-emitting material 120 can be positioned relative to the light-emitting diode 118 so that heat transfer from the light-emitting diode 118 to the light-emitting diode 118 is possible. More specifically, the light-emitting material 120 is positioned so that heat transfer is possible by either thermal radiation or thermal conduction, or both (more preferably by thermal conduction). Thus, as an example, as shown in Figure 2, the light-emitting material 120 can maintain thermal and / or physical contact with the light-emitting diode 118. As a result, the temperature of the light-emitting material 120 and the temperature of the light-emitting diode 118 are generally linked.

[0170] As shown in Figure 2, the light source 114, particularly the phosphor LED 122, may include further components such as at least one lateral coating 162 covering at least one surface (e.g., the top, bottom, and / or one or more sides of the substrate 154, contact pad 158, light-emitting diode 118, and light-emitting material 120). Specifically, the lateral coating 162 can cover any gaps and / or voids that may exist in the laminated structure of the light source 114 as shown in Figure 2. Further components of the light source 114, particularly those not shown in Figure 2, are feasible. Generally, the light source 114, particularly the phosphor LED 122, may be enclosed in a single housing (not shown in Figure 2) or not. Thus, the LED 118 and at least one light-emitting material 120 for converting the primary light generated by the light-emitting diode 118 may be housed in a common housing in particular. Alternatively, as shown in Figure 2, the LED 118 may be unhousing or a bare LED 118.

[0171] Figure 3 is a flowchart illustrating one embodiment of a method for acquiring spectral information about at least one object 112. This method includes the following steps, which may be performed in a predetermined order. However, different orders are also possible. In particular, one, more, or all method steps may be performed once or repeatedly. Furthermore, the method steps may be performed sequentially, or one or more method steps may be performed in a timely overlap, in parallel, and / or in combination. This method may include additional method steps not described.

[0172] This method includes the following steps: a) Providing at least one spectrometer apparatus 110 according to the present invention (referred to as reference no. 164) (for example, according to the embodiment of Figure 1 and / or according to other embodiments disclosed herein); b) A step of illuminating an object 112 with illumination light 116 generated by a light source 114 (referred to as reference number 166), wherein the light source 114 includes 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; c) A step of detecting detection light 130 (as shown in reference no. 168), specifically detection light 130 from an object 112 and / or detection light 112 guided from a light source 114 to a broadband detector 128 without interaction with the object 112, using at least one broadband detector 128, in a spectral range that at least partially includes the spectral range of primary light and the spectral range of secondary light, wherein the broadband detector 128 is configured to generate at least one primary detector signal when it detects detection light 130 in the spectral range of primary light, and the broadband detector 128 is configured to generate at least one secondary detector signal when it detects detection light 130 in the spectral range of secondary light; and d) A step of evaluating the primary and secondary detector signals generated by the broadband detector 128 using the evaluation unit 136 (indicated by reference number 170), wherein the responsiveness information 137 of the broadband detector 128 is determined from either the primary or secondary detector signal, and spectral information of the object 112 is derived from the other of the primary or secondary detector signal, taking into consideration the responsiveness information 137 of the broadband detector 128.

[0173] Step d) may include evaluating the primary detector signal generated by the broadband detector 128, determining the responsiveness information 137 of the broadband detector 128 from the primary detector signal, and determining the spectral information about the object 112 from the secondary detector signal, taking into account the responsiveness information 137 of the broadband detector 128 determined from the primary detector signal.

[0174] The spectrometer apparatus 110 may further include at least one drive unit 138 for electrically driving the light source 114, as described above. Specifically, this method may include, in step b), driving the light-emitting diode 118 with the drive unit 138 at at least one drive frequency. The drive frequency may be higher than the reciprocal of the time constant τ of the light-emitting material 120. Specifically, this mode of operation of the light source 114 is also called pulse width modulation. The evaluation in step d) may include distinguishing between the primary detector signal and the secondary detector signal using a Fourier transform, in particular the fast Fourier transform. As shown in Figure 5 below, the light-emitting diode 118 can be modulated using a pulse train, specifically the drive unit 138.

[0175] Figure 4 shows a spectral sensitivity characteristic diagram of an exemplary broadband detector 128. Specifically, the diagram in Figure 4 shows the spectral sensitivity, including the normalized signal intensity by an arbitrary unit 172 as a function of wavelength 174. As understood in Figure 4, the broadband detector 128 may be configured to detect detection light 130 from an object 112 in a spectral range of 1000 nm to 3000 nm.

[0176] Figure 5 shows a diagram of pulse width modulation. Specifically, in Figure 5, the drive pulse applied to the light-emitting diode 118 (shown in the time domain and indicated by reference number 186) and the resulting secondary light pulse (shown in the time domain and indicated by reference number 188) are shown. As shown in Figure 6, the light-emitting diode 118 can be subjected to a pulse train 190 having a drive frequency exceeding the reciprocal of the time constant τ of the light-emitting material 120 using a drive unit 138. Since the pump LED 118 may be faster than the light-emitting material 120, the secondary light pulse may not keep up with the high-speed drive of the LED 118. Therefore, the pulse shape applied to the excitation LED 118 is selected so that the frequency domain information obtained from the fast Fourier transform provides spectral information from both the primary and secondary detector signals using a single detector 134.

[0177] As schematically shown in Figure 5, the pulse train 190 comprises a continuous pulse train, where individual pulses 192 are high-frequency, while the pulse package 194 is low-frequency, specifically to excite at least one substance irradiated by the pulse train 190. In particular, the high-frequency train of individual pulses 192 is modulated by the low frequency of the pulse package 194, which can be represented by the modulation frequency f1. As described above, the converter time constant τ g and τ d By using this, the modulation frequency f1 can be expressed by equation (3). Here, τ g τd represents the growth time constant, and τd represents the decay time constant. f1≫1 / (max(τ g ,τ d )) (3)

[0178] A notable advantage of this pulse train 190 is that it can simultaneously provide primary light with high frequencies from individual pulses 192 generated by the light-emitting diode 118 and secondary light with a low modulation frequency f1 from the pulse package 194. Here, the low modulation frequency f1 of the pulse package makes it possible to simultaneously provide primary light with high frequencies from individual pulses 192 generated by the secondary light-emitting diode 118 and secondary light with a low modulation frequency f1 from the pulse package 194. Here, the low modulation frequency f1 of the pulse package is selected so that the light-emitting material 120 can follow the excitation by the pulse package 194 provided by the pulse train. Here, frequency multiplexing makes it possible to distinguish between the primary detector signal and the secondary detector signal generated by a single detector 134. In this way, by taking into account the temperature information of the light source 114 from the detector signal generated by the single detector 134, it is possible to determine the responsiveness information 137 on the broadband detector 128 and derive spectral information about the object 112. [Explanation of Symbols]

[0179] 110 Spectrometer equipment 112 Object 114 Light source 116 Illumination light 118 Light-emitting diodes 120 Luminescent Materials 121 Semiconductor Materials 122 Phosphorous light-emitting diodes 123 First optical path 124 LED Dies 125 Second optical path 126 Housing 127 Thermal bonding 128 Broadband detectors 130 detection light 131 First detector element 132 Multiple detector elements 133 Second detector element 134 Single detector 136 evaluation units 137 Responsiveness Information 138 Drive Unit 140 Current source 142 Voltage measuring device 144 Data Processing Devices 146 Pre-treatment device 148 Data Storage Devices 150 Optical Components 152 wavelength selective element 154 circuit boards 156 Ceramic substrate 158 Contact Pads 160 Converter Unit 162 Side Court 164 Provision of Spectrometer Equipment 166 Illumination of the object 168 Detection of detected light 170 Evaluation of at least one of the primary detector signal and the secondary detector signal 172 Normalized signal strength 174 wavelength 186 drive pulses 188 Secondary light pulse 190 pulse train 192 individual pulses 194 pulse package

Claims

1. A spectrometer device (110) for acquiring spectral information relating to at least one object (112), comprising the following configuration: i. At least one light source (114) for generating illumination light (116) for illuminating an 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; ii. At least one broadband detector (128) for detecting detection light (130) in a spectral range that at least partially includes the spectral range of primary light and the spectral range of secondary light, wherein the broadband detector (128) is configured to generate at least one primary detector signal when detection light (130) is detected in the spectral range of primary light, and further configured to generate at least one secondary detector signal when detection light (130) is detected in the spectral range of secondary light; iii. At least one evaluation unit (136) for evaluating the primary and secondary detector signals generated by the broadband detector (128), determining the responsiveness information (137) of the broadband detector (128) from either the primary or secondary detector signal, and deriving spectral information of the object (112) from the other of the primary or secondary detector signal, taking into account the responsiveness information (137) of the broadband detector (128); iv. at least one first optical path (123), the first optical path (123) being configured to allow at least a portion of the primary light or illumination light to propagate from the light source (114) to the broadband detector (128) without interacting with the object (112); and v. At least one second optical path (125) configured to allow illumination light (130) to propagate from the light source (114) to the broadband detector (128) by interacting with the object (112) at least once; A spectrometer (110) is provided, wherein the first optical path (123) includes at least one optical element configured to direct at least a portion of the primary light from the light source (114) to a broadband detector (128) without interacting with the object (112).

2. The spectrometer apparatus (110) according to claim 1, wherein the first optical path (123) is configured to allow a portion of the primary light to propagate to the broadband detector (128) without passing through the light-emitting material (120), or the first optical path (123) is configured to allow a portion of the illumination light (116) to propagate from the light source (114) to the broadband detector (128) without interacting with the object (112), wherein the illumination light (116) includes at least a portion of primary light and secondary light.

3. The spectrometer apparatus (110) according to claim 1 or 2, wherein the first optical path (123) includes at least one optical element configured to guide at least a portion of the primary light or illumination light (116) from the light source (114) to the broadband detector (128) without interacting with the object (112), and the optical element includes at least one optical element selected from the group consisting of a beam splitter, a dichroic filter, a bandpass filter, a longpass filter, a shortpass filter, a dispersive element such as a prism, and a diffracting element such as a grating.

4. The spectrometer apparatus (110) according to claim 1 or 2, wherein the broadband detector (128) is configured to generate a primary detector signal by detecting detection light (130) in the first optical path (123), and the broadband detector (128) is configured to generate a secondary detector signal by detecting detection light (130) in the second optical path (125).

5. The spectrometer apparatus (110) according to claim 4, wherein the evaluation unit (136) is configured to determine the responsiveness information (137) of the broadband detector (128) from the primary detector signal, and to determine the spectral information of the object (112) from the secondary detector signal, taking into consideration the responsiveness information (137) of the broadband detector (128) determined from the primary detector signal.

6. The spectrometer apparatus (110) according to claim 1 or 2, wherein the broadband detector (128) includes a plurality of detector elements (131, 132, 133) for detecting detection light (130) in the spectral ranges of primary and secondary light.

7. The spectrometer apparatus (110) according to claim 1 or 2, further comprising at least one drive unit (138) for electrically driving a light source (114), the drive unit (138) configured to drive a light-emitting diode (118) at at least one drive frequency, the drive frequency being greater than the reciprocal of the time constant τ of the light-emitting material, and the evaluation unit (136) configured to distinguish between a primary detector signal and a secondary detector signal by demodulating using a Fourier transform, in particular a fast Fourier transform.

8. The spectrometer apparatus (110) according to claim 1 or 2, wherein the light source (114) includes a phosphor light-emitting diode (122).

9. A method for obtaining spectral information relating to at least one object (112), comprising the following steps: a) The step of preparing at least one spectrometer apparatus (110) according to claim 1 or 2; b) A step of irradiating an object (112) with illumination light (116) generated by a light source (114), wherein the light source (114) includes 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; c) A step of detecting detection light (130) in a spectral range that includes at least partially the spectral ranges of primary and secondary light using at least one broadband detector (128), wherein the broadband detector (128) is configured to generate at least one primary detector signal when it detects detection light (130) in the spectral range of primary light, and to generate at least one secondary detector signal when it detects detection light (130) in the spectral range of secondary light; d) Using an evaluation unit (136), evaluate the primary and secondary detector signals generated by the broadband detector (128), determine the responsiveness information (137) of the broadband detector (128) from either the primary or secondary detector signal, and derive the spectral information of the object (112) from the other of the primary or secondary detector signal, taking into consideration the responsiveness information (137) of the broadband detector (128). Methods that include...

10. The method according to claim 9, wherein step d) includes determining responsiveness information (137) of a broadband detector (128) from a primary detector signal, and determining spectral information of an object (112) from a secondary detector signal, taking into consideration the responsiveness information (137) of the broadband detector (128) determined from the primary detector signal.

11. The method according to claim 9, wherein the spectrometer apparatus (110) further comprises at least one drive unit (138) for electrically driving a light source (114), the method comprising electrically driving the light-emitting diode (118) with the drive unit (138) at at least one drive frequency, the drive frequency being higher than the reciprocal of the time constant τ of the light-emitting material (120), and the evaluation in step d) comprises distinguishing between a primary detector signal and a secondary detector signal using a Fourier transform, in particular a fast Fourier transform.

12. The method according to claim 9, particularly in step b), which includes using a pulse train that is high frequency for individual pulses generated by the light-emitting diode (118) but low frequency for a pulse package applied to the light-emitting material (120), wherein the distinction between a primary detector signal and a secondary detector signal includes frequency multiplexing of a composite detector signal generated by a single broadband detector (128, 134), and the composite detector signal includes both the primary and secondary detector signals.

13. A computer program that, when executed by the spectrometer apparatus (110) according to claim 1 relating to the spectrometer apparatus (110), includes instructions causing the spectrometer apparatus (110) to perform at least steps b) through d) of the method according to claim 9 relating to the method.

14. A computer-readable storage medium that, when executed by the spectrometer apparatus (110) according to claim 1 relating to the spectrometer apparatus (110), includes an instruction causing the spectrometer apparatus (110) to perform at least steps b) through d) of the method according to claim 9 relating to the method.

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