LED temperature measurement settings via buffered direct injection (BDI) circuits

Abstract

A spectrometer apparatus (110) and method of obtaining spectroscopy information about at least one object (112) are disclosed. The spectrometer device (110) comprises: i. At least one light source (114) for generating illumination light (116) for illuminating the object (112); ii. At least one detector (128) for detecting the detection light (130) from the object (112) and generating at least one detector signal; iii. At least one drive unit (138) for electrically driving the light source (114); iv. At least one multi-channel readout integrated circuit (139) wherein each channel of the multi-channel readout integrated circuit (139) comprises at least one buffered direct injection (BDI) circuit (141) wherein the BDI circuit (141) is configured to read out the detector signal wherein the BDI circuit (141) is configured to generate at least one item of information regarding an electrically measurable amount required to drive the light source (114) wherein the BDI circuit (141) is configured to drive the light source (114). A multi-channel readout integrated circuit (139) comprising at least one multi-channel readout application-specific integrated circuit (ASIC) (142) configured for synchronously sampling the detector signal and the item of information regarding the electrically measurable amount required to drive the light source (114); and v. At least one evaluation unit (136) for evaluating at least one detector signal generated by the detector (128) and for deriving the spectroscopy information about the object (112) from the detector signal, the evaluation unit (136) is configured for taking into account the item of information regarding the electrically measurable quantity required to drive the light source (114) when deriving the spectroscopy information from the detector signal.

Description

Technical Field

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

[0002] Spectrometer devices are known to be efficient tools for obtaining information about the spectral properties of an object when emitting, irradiating, reflecting and / or absorbing light. Spectrometer devices can therefore assist in analyzing samples or other tasks where information about the spectral properties of an object is of interest.

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

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

[0005] US Pat. No. 8,164,050 B2 describes a multi-channel light source assembly for downhole spectroscopy. The assembly includes individual light sources that generate optical signals spanning a spectral range of wavelengths. A combining assembly optically combines the generated signals into a combined signal, while a routing assembly separates the combined signal into a reference channel and a measurement channel. Control circuitry electrically coupled to the light sources modulates each of the light sources at a unique or independent frequency during operation.

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

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

[0008] Spectrometers are often subject to various internal and external influences (such as environmental influences) that may affect the results of spectral measurements. To correct for and / or compensate for these influences, various calibration and / or correction methods are known. These calibration methods can be performed once or several times by the manufacturer, for example, under laboratory conditions. However, various online calibration techniques are also known, which can be performed by performing one or more calibration and / or correction steps between two spectral measurements or even during a measurement.

[0009] US 09360366 B1 discloses a self-referencing spectrometer that utilizes a shared aperture as an optical input to simultaneously automatically calibrate and measure the spectrum of a physical object. The simultaneous measurement and self-calibration capabilities enable it to be used as an accessory spectrometer on a mobile computing device, eliminating the need for offline calibration using an external reference light source. The acquired spectral information and captured images can be distributed via a wireless communication network via the mobile computing device.

[0010] DE 102014013848 B4 discloses a miniature spectrometer (specifically, an NIR miniature spectrometer for mobile applications in battery-powered terminals) to overcome the limitations of the aforementioned system configurations in terms of non-miniaturization and hand-holding. It also discloses a miniature spectrometer system and a calibration method. This miniaturized NIR spectrometer design does not require active temperature stabilization. Instead, according to the present invention, as part of a factory temperature calibration step, the spectral sensitivity function (QE) is recorded at several levels within the expected operating temperature range. λ = f(T); measured using the integrated temperature sensor).

[0011] WO 2019 / 191698 A2 relates to a self-referencing spectrometer for simultaneously measuring a background or reference spectral density and a sample or other spectral density. The self-referencing spectrometer comprises an interferometer optically coupled to receive an input beam and guide the input beam along a first optical path to generate a first interference beam and guide the input beam along a second optical path to generate a second interference beam, wherein each interference beam is generated before an output end of the interferometer. The spectrometer further comprises: a detector optically coupled to simultaneously detect a first interference signal generated from the first interference beam and a second interference signal generated from the second interference beam; and a processor configured to process the first interference signal and the second interference signal and to use the second interference signal as a reference signal when processing the first interference signal.

[0012] US 20210293620 A1 discloses a spectrometer comprising: an illumination device for illuminating a spectral measurement region; a detection unit for detecting electromagnetic radiation from the spectral measurement region; and a spectral element disposed in a beam path between the illumination device and the detection unit. The illumination device comprises: a light-emitting diode having a first central wavelength, the light-emitting diode being designed to emit first electromagnetic radiation having a first spectrum; and a light-emitting element for converting a first component of the first electromagnetic radiation having the first spectrum into second electromagnetic radiation having a second spectrum. The first central wavelength is 550 nm or 3000 nm, or has a value between 550 nm and 3000 nm. The first spectrum and the second spectrum overlap.

[0013] US 06667802 B2 discloses a method for calibrating a spectral detection system. The method includes: providing a plurality of packages, each of the plurality of packages containing a group of articles, wherein each group of articles has a known composition; measuring reflectance values ​​of each group of articles to thereby obtain a reference reflectance value set; normalizing the reference reflectance value set to thereby generate a normalized reference reflectance value set; and storing the normalized reference reflectance value set.

[0014] US 06717669 B2 discloses an automatically calibrated spectrometer and method that measures the transmission or reflectance of a sample as a function of wavelength without requiring lengthy calibration. A reflectance spectrometer and a transmission spectrometer, as well as an automatically calibrated method for use therewith, are disclosed. Light is focused onto a sample using a lens or similar optical element that transmits the light to the sample, reflects the light impinging on it, and transmits the light reflected from the sample. If the light reflected from the first lens and the sample is monitored, very useful information about the response of the system over time can be obtained. The reflected light from the first lens and the sample is monitored, and the reflected light is used to correct for changes in the system over time.

[0015] US 09448114 B2 discloses a spectrometer comprising a plurality of isolated optical channels, each of which comprises a plurality of isolated optical paths. The isolated optical paths reduce crosstalk between the optical paths, reduce the length of the spectrometer, and improve resolution. In many embodiments, the isolated optical paths comprise isolated parallel optical paths, which significantly reduce the length of the device. In many embodiments, each isolated optical path extends from a filter in a filter array, through a lens in a lens array, through a channel in a support array, and to a region of a sensor array. Each region of the sensor array comprises a plurality of sensor elements, wherein the position of the sensor element corresponds to a wavelength of received light, the wavelength being based on the angle of the light received at that position, the focal length of the lens, and the center wavelength of the filter.

[0016] US Pat. No. 10,841,563 B1 discloses a sensor and sensor platform for autonomous systems. The sensor and its platform sense, perform signal or data processing, and make decisions locally at the sensing point. More specifically, the sensor and its platform emulate human-like or human-like decision-making capabilities by combining data from multiple sensors detecting different data sets, and combining this data in a series of data processes that enable autonomous decision-making. Furthermore, the sensor platform combines the functionality of multiple sensors in a single hypersensor with that of multiple sensors placed on a common carrier or platform.

[0017] Tetzlaff T. et al., in "Hardware Implementation of LED Forward Voltage Measurement for Junction Temperature Estimation," 19th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE), 2018, describe extending LED driver circuitry with measurement components and signal processing hardware to accurately detect the LED junction temperature. This information can be used by the driver to control the current and, therefore, the temperature of the LED device. The focus of this scientific publication is LED temperature measurement based on LED forward voltage measurements.

[0018] Despite the numerous advantages of known methods and devices, several technical challenges remain in the field of spectroscopy and spectroscopic equipment, particularly in the near-infrared range. Specifically, optoelectronic components (such as light sources, detectors, and readout electronics) often exhibit strong temperature dependencies. If this temperature dependency is not corrected, drift due to temperature variations can reduce the repeatability of spectrometer measurements.

[0019] Typically, these technical challenges can be avoided by stabilizing the temperature of temperature-sensitive optoelectronic components using additional hardware (e.g., thermoelectric coolers) or by monitoring and correcting temperature changes of temperature-sensitive optoelectronic components (e.g., by direct monitoring or by monitoring subsequent changes in electrical and / or optical properties of the corresponding components).

[0020] However, in the latter case, the monitored characteristics can have different properties, such as voltage, current, resistance, power consumption, optical efficiency, spectral shift, etc. Monitoring each of these characteristics may require different circuits with different electrical components. Moreover, the changes in these characteristics due to temperature variations may be very small compared to their initial values. Therefore, the resolution of the monitoring system must generally be high. Overall, these constraints can result in complex and expensive systems that take up a large space. Such complex systems are often not feasible for size- and cost-sensitive applications.

[0021] Problem to be solved

[0022] Therefore, it is desirable to provide an apparatus and a method that at least partially solve the above technical challenges. In particular, it is an object of the present invention to provide a spectrometer apparatus and a method for obtaining spectroscopic information about at least one object, which spectrometer apparatus and method minimize the hardware effort for correcting external and / or internal influences (such as temperature) of the spectrometer apparatus. Summary of the Invention

[0023] This problem is solved by a spectrometer device for obtaining spectroscopic information about at least one object, a method for obtaining spectroscopic information about at least one object, a computer program, and a computer-readable storage medium having the features of the independent claims. Advantageous embodiments are listed in the dependent claims and throughout the description, which can be implemented individually or in any arbitrary combination.

[0024] In a first aspect of the present invention, a spectrometer apparatus for obtaining spectroscopic information about at least one object is disclosed.

[0025] As used herein, the term "spectrographic device" is a broad term and is to be given its ordinary and customary meaning for those skilled in the art and is not limited to a special or customary meaning. The term may specifically, but is not limited to, refer to an optical device configured to obtain at least one item of spectral information about at least one object. Specifically, the at least one spectral information item may refer to at least one optical property or optically measurable property determined as a function of wavelength for one or more different wavelengths. More specifically, the optical property or optically measurable property and the at least one spectral information item may relate to at least one property that characterizes at least one of transmission, absorption, reflection, and emission of the at least one object, either intrinsically or after exposure to external light. The at least one optical property may be determined for one or more wavelengths. The spectroscopic device may specifically be a device capable of recording signal intensities for corresponding wavelengths or subregions (e.g., wavelength intervals) of a spectrum, wherein the signal intensities may be provided as electrical signals that can be used for further evaluation.

[0026] By way of example, a spectrometer device may be or may include a device that allows for measuring at least one spectrum (e.g., for measuring spectral flux, in particular as a function of wavelength or detection wavelength). By way of example, the spectrum may be acquired in absolute units or relative units (e.g., relative to at least one reference measurement). Thus, by way of example, the acquisition of at least one spectrum may specifically focus on measuring spectral flux (in W / nm) or a spectrum (in W) relative to at least one reference material, which may describe a material property (e.g., a change in reflectivity with 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 device.

[0027] Specifically, at least one spectrometer device can be a diffuse reflectance spectrometer device configured to obtain 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 can be or include an absorption spectrometer and / or a transmission spectrometer. In particular, measuring a spectrum with the spectrometer device can include measuring absorption in a transmission configuration. Specifically, the spectrometer device can be configured to measure absorption in a transmission configuration. However, as outlined above, other types of spectrometer devices are also possible.

[0028] As will be further detailed below, a spectrometer apparatus includes at least one light source, which can be, for example, at least one of a tunable light source, a light source having at least one fixed emission wavelength, and a broadband light source. As will be further detailed below, the spectrometer apparatus further includes at least one detector configured to detect light, such as at least one of light transmitted, reflected, or emitted from at least one object. As will be further detailed below, the spectrometer apparatus can further include at least one wavelength-selective element, such as at least one of a grating, a prism, and a filter (e.g., a variable-length filter having varying transmission characteristics across its lateral extension). The wavelength-selective element can be used to separate incident light into a spectrum of component wavelength signals, the respective intensities of which are determined using a detector (e.g., a detector array as described in more detail below).

[0029] The spectrometer device may specifically be a portable spectrometer device. As used herein, the term "portable" is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not limited to a special or customized meaning. The term may specifically refer to, but is not limited to, the property of at least one object being moved by human power (such as by a single user). In particular, the weight of the object characterized by the term "portable" may not exceed 10 kg, specifically not exceed 5 kg, more specifically not exceed 1 kg or even not exceed 500 g. Additionally or alternatively, the size of the object characterized by the term "portable" may be such that the object extends no more than 0.3 m in any dimension, specifically no more than 0.2 m in any dimension. In particular, the volume of the object may not exceed 0.03 m³, specifically not more than 0.01 m³, more specifically not more than 0.001 m³ or even not more than 500 mm 3 . In particular, as an example, the portable spectrometer device may have dimensions of, for example, 10 mm × 10 mm × 5 mm. In particular, the portable spectrometer device may be part of a mobile device, such as a laptop computer, a tablet computer, a mobile phone (such as a smartphone), a smartwatch and / or a wearable computer (also referred to as a “wearable device”, such as a body-worn computer (such as a wristband or a watch)), or may be attachable to a mobile device. In particular, the weight of the spectrometer device, in particular the portable spectrometer device, may be in the range of 1 g to 100 g, more particularly in the range of 1 g to 10 g.

[0030] As used herein, the term "spectroscopy information" (also referred to as "spectral information" or "spectral information item") is a broad term and is to be given its ordinary and customary meaning for those skilled in the art and is not limited to a special or customary meaning. The term may specifically, but is not limited to, an item of information about at least one object and / or radiation emitted by at least one object, characterizing at least one optical property of the object, more specifically, characterizing, for example, at least one item of information that qualitatively and / or quantifies at least one of the transmission, absorption, reflection, and emission of the at least one object. By way of example, at least one item of spectral information may include at least one item of intensity information, such as information about the intensity of at least one of light transmitted, absorbed, reflected, or emitted by the object, for example, as a function of wavelength or wavelength sub-range within one or more wavelengths (e.g., within a wavelength range). Specifically, the intensity information may correspond to, or be derived from, a signal intensity (particularly an electrical signal) recorded by a spectrometer device that is associated with a wavelength or wavelength range of the spectrum.

[0031] The spectrometer device can be specifically configured to acquire at least one spectrum, or at least a portion of a spectrum, of detection light propagating from the object to the spectrometer. The spectrum can describe a radiometric unit of spectral flux, for example given in watts per nanometer (W / nm), or in other units, for example as a function of the wavelength of the detection light. Thus, the spectrum can describe the optical power of light within a specific wavelength band, for example in the NIR spectral range. The spectrum can include one or more optical variables that vary with wavelength, such as power spectral density, an electrical signal obtained by optical measurement, etc. As an example, the spectrum can indicate the power spectral density and / or spectral flux of the object (e.g., a sample), for example relative to a reference sample, such as the transmittance and / or reflectance of the object (particularly the sample).

[0032] As an example, the spectrum may include at least one measurable optical variable or property of the detection light and / or the object, the optical variable or property being in particular a function of the illumination light and / or the detection light. As an example, the at least one measurable optical variable or property may include at least one radiometric quantity, such as at least one of spectral density, power spectral density, spectral flux, radiant flux, radiant intensity, spectral radiant intensity, irradiance, and spectral irradiance. Specifically, as an example, the spectrometer device (in particular the detector) may measure power in Watts per square meter (W / m 2 ) or more specifically measured in watts per square meter per nanometer (W / m 2 Based on the measured quantities, the spectral flux in Watts per nanometer (W / nm) and / or the radiant flux in Watts (W) can be determined (e.g., calculated) by taking into account the area of ​​the detector.

[0033] As used herein, the term "object" is a broad term and is to be given its ordinary and customary meaning to one of ordinary skill in the art and is not limited to a special or customized meaning. The term may specifically refer to, but is not limited to, any body selected from animate and inanimate objects. Thus, by way of example, at least one object may include one or more items and / or one or more parts of an item, wherein at least one item or at least one part thereof may include at least one component that can provide a spectrum suitable for investigation. Additionally or alternatively, the object may be or include one or more organisms and / or one or more parts thereof, such as one or more body parts of a human (e.g., a user) and / or an animal. Specifically, the object may include at least one sample that can be analyzed in whole or in part by spectroscopic methods. By way of example, the object may be or include at least one of the following: human or animal skin; edibles, such as fruit; plastics; and textiles.

[0034] The spectrometer device comprises at least one light source for generating illumination light for illuminating an object.

[0035] As used herein, the term "light" is a broad term and is to be given its ordinary and customary meaning to those skilled in the art and is not limited to a special or customary meaning. The term may specifically refer to, but is not limited to, electromagnetic radiation in one or more of the infrared spectral range, the visible spectral range, and the ultraviolet spectral range. As used herein, the term "ultraviolet spectral range" generally refers to electromagnetic radiation with a wavelength of 1 nm to 380 nm, preferably 100 nm to 380 nm. Furthermore, in accordance in part with the version of standard ISO-21348 in effect as of the date of this document, the term "visible spectral range" generally refers to the spectral range of 380 nm to 760 nm. The term "infrared spectral range" (IR) generally refers to electromagnetic radiation in the range of 760 nm to 1000 µm, of which the range of 760 nm to 1.5 µm is generally referred to as the "near infrared spectral range" (NIR), the range of 1.5 µm to 15 µm is referred to as the "mid infrared spectral range" (MidIR), and the range of 15 µm to 1000 µm is referred to as the "far infrared spectral range" (FIR). Preferably, the light used for the typical purposes of the present invention is light in the infrared (IR) spectral range, more preferably light in the near-infrared (NIR) and / or mid-infrared (MidIR) spectral range, particularly light with a wavelength of 1 µm to 5 µm, preferably 1 µm to 3 µm. This is because many material properties or chemical composition characteristics of an object can be derived from the NIR spectral range. However, it should be noted that spectral analysis in other spectral ranges is also applicable and falls within the scope of the present invention.

[0036] Therefore, as used herein, the term "light source" is a broad term and is to be given its ordinary and customary meaning to those of ordinary skill in the art and is not limited to a special or customized meaning. The term may specifically refer to, but is not limited to, any device configured to generate or provide light in the sense defined above. The light source may specifically be or may include at least one electric light source, such as an electrically driven light source.

[0037] As used herein, the term "irradiation" is a broad term and is to be given its ordinary and customary meaning to those of ordinary skill in the art and is not limited to a special or customized meaning. The term may specifically refer to, but is not limited to, the process of exposing at least one element to light.

[0038] In spectroscopy, it is important to distinguish between various light sources and light paths. In the context of the present invention, the nomenclature used first refers to light propagating from a light source to an object as "illuminating light" (or "illumination light"). Secondly, light propagating from an object to a detector is referred to as "detection light." Detection light can include at least one of the following: illumination light reflected by an object, illumination light scattered by an object, illumination light transmitted by an object, or luminescence light generated by an object (e.g., phosphorescence or fluorescence generated by an object after optical, electrical, or acoustic excitation of the object by the illumination light). Therefore, detection light can be generated directly or indirectly by illumination of an object with illumination light.

[0039] Furthermore, as will be described in more detail below, within the light source itself, a distinction can be made between various light sources, such as primary and secondary light sources. Thus, "primary light" (also referred to as "pump light"), as will be described in more detail below, can be generated by a primary light source (such as at least one light-emitting diode) and can subsequently be transformed into "secondary light," such as by using light conversion (e.g., via one or more phosphor materials). The illumination light can be or include at least one of the primary light or a portion thereof, the secondary light or a portion thereof, or a mixture of the primary and secondary light.

[0040] In general, the light source can be implemented in various ways. For example, the light source can be part of the spectrometer device, such as within the spectrometer housing. However, alternatively or additionally, the at least one light source can also be arranged outside the housing, such as as a separate light source. The light source can be arranged separately from the object and illuminate the object from a distance.

[0041] The light source can be specifically configured for emitting light in a spectral range that at least partially includes the infrared spectral range, specifically the near-infrared spectral range, more specifically in the spectral range from 760 nm to 3 µm, more specifically in the spectral range from 1 µm to 3 µm, preferably from 1.3 µm to 2.5 µm, more preferably from 1.5 µm to 2.2 µm.

[0042] The light source may include at least one light source selected from the group consisting of: an incandescent lamp; a light emitting diode (LED); a laser, in particular a laser diode, a solid-state laser, a gas laser, or a quantum cascade laser; a plasma light source; a low-pressure discharge lamp, in particular a low-pressure fluorescent lamp; a high-pressure discharge lamp; and an electric light source. A low-pressure discharge lamp may refer to any gas discharge lamp that operates under normal conditions at a gas pressure less than 1% of atmospheric pressure. A high-pressure discharge lamp may refer to any gas discharge lamp that operates under normal conditions at a gas pressure greater than 10% of atmospheric pressure. An electric light source may refer to any type of light source that can be driven by means of current and voltage.

[0043] The light source may specifically include at least one light-emitting diode (LED) and at least one luminescent material for photoconverting primary light generated by the LED. Specifically, the illumination light may be a combination of the primary light and light generated by photoconversion of the luminescent material, or light generated by photoconversion of the luminescent material (also referred to as secondary light).

[0044] As used herein, the term "light emitting diode," or simply "LED," is a broad term and is to be given its ordinary and customary meaning to those of ordinary skill in the art and is not to be limited to a special or customary meaning. The term may specifically refer to, but is not limited to, an optoelectronic semiconductor device capable of emitting light when an electric current flows through the device. Optoelectronic semiconductor devices can be configured to generate light due to one or more of a variety of physical processes, including spontaneous emission, induced emission, decay of metastable excited states, and the like. Thus, by way of example, a light emitting diode may include one or more of the following: a light emitting diode based on spontaneous emission of light, particularly an organic light emitting diode, a superluminescent light emitting diode (sLED), or a laser diode (LD). Hereinafter, the abbreviation "LED" will be used to refer to any type of light emitting diode, without narrowing down the possible embodiments of a light emitting diode to any of the aforementioned physical principles or setups. Specifically, an LED may include at least two layers of semiconductor material, wherein light may be generated at at least one interface between the at least two semiconductor material layers, particularly due to the recombination of positive and negative charges (e.g., electron-hole recombination). The at least two semiconductor material layers may have different electrical properties, such as at least one of the layers being an n-doped semiconductor material and at least one of the layers being a p-doped semiconductor material. Thus, as an example, an LED may include at least one pn junction and / or at least one pin structure. However, it should be noted that other device structures are also possible. The at least one semiconductor material may specifically be or may include at least one inorganic semiconductor material. However, it should be noted that organic semiconductor materials may be used in addition or alternatively.

[0045] Typically, as will be further detailed below, an LED can convert electrical current into light, specifically into primary light, more specifically into blue primary light. Thus, the LED can specifically be a blue LED. The LED can be configured to generate primary light, also referred to as "pump light." Thus, the LED can also be referred to as a "pump LED." The LED can specifically include at least one LED chip and / or at least one LED die. Thus, the semiconductor element of the LED can include a bare LED chip.

[0046] Various types of LEDs suitable for generating primary light are known to those skilled in the art and can also be used in the present invention. In particular, pn junction diodes can be used. By way of example, one or more LEDs selected from the group consisting of indium gallium nitride (InGaN)-based LEDs, GaN-based LEDs, InGaN / GaN alloy-based LEDs, or combinations thereof, and / or other LEDs can be used. Additionally or alternatively, quantum well LEDs, such as one or more quantum well LEDs based on InGaN, can also be used. Additionally or alternatively, superluminescent LEDs (sLEDs) and / or quantum cascade lasers can be used.

[0047] As used herein, the term "luminescence" is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not limited to a special or customized meaning. The term may specifically refer to, but is not limited to, the process of spontaneous emission of light by a substance that is not caused by heat. In particular, luminescence may refer to radiation from a cold body. More specifically, luminescence may be initiated or stimulated by irradiation with light, in which case luminescence is also referred to as "photoluminescence". In the context of the present invention, the property of a material that is capable of luminescence is referred to by the adjective "luminescent". At least one luminescent material may specifically be a photoluminescent material, i.e. a material that is capable of emitting light after absorbing a photon or excitation light. In particular, the luminescent material may have a positive Stokes shift, which generally may refer to the fact that the secondary light is red-shifted relative to the primary light.

[0048] Thus, at least one luminescent material can form at least one converter (also called a light converter) that converts primary light into secondary light having different spectral characteristics than the primary light. Specifically, the spectral width of the secondary light can be greater than the spectral width of the primary light and / or the emission center of the secondary light can be shifted (specifically, red-shifted) compared to the primary light. Specifically, at least one luminescent material can have absorption in the ultraviolet and / or blue spectral ranges and emission in the near-infrared and / or infrared spectral ranges. Thus, typically, the luminescent material or converter can form at least one component of a phosphor LED, which concentrates primary light or pump light, particularly in the blue spectral range, into light having a longer wavelength, for example, in the near-infrared or infrared spectral range.

[0049] Various types of conversion and / or luminescence are known and can be used in the context of the present invention. Thus, in particular, the conversion can occur via a dipole-allowed transition in the luminescent material (also known as fluorescence) and / or via a dipole-forbidden, and therefore longer-lived, transition in the luminescent material (often also known as phosphorescence).

[0050] Thus, the luminescent material may specifically form at least one converter or light converter. The luminescent material may form at least one of a converter sheet, a luminescent coating (specifically a fluorescent coating) on ​​an LED, and a phosphor coating on an LED. As an example, the luminescent material may include one or more of the following materials: cerium-doped YAG (YAG:Ce 3+ or Y3Al5O 12 :Ce 3+ ); rare earth-doped Sialon; copper and aluminum co-doped zinc sulfide (ZnS:Cu,Al).

[0051] Together, an LED and a luminescent material can form a so-called "phosphor LED." Therefore, as used herein, the term "phosphor light-emitting diode," or simply "phosphor LED," is a broad term and is to be given its ordinary and customary meaning for those skilled in the art and is not limited to a special or customary meaning. The term may specifically, but is not limited to, the combination of at least one light-emitting diode configured to generate primary light, or pump light, and at least one luminescent material (also referred to as a "phosphor") configured to photoconvert the primary light generated by the light-emitting diode. A phosphor LED can form a packaged LED light source comprising an LED die (e.g., a blue LED emitting blue pump light) and a phosphor that, for example, fully or partially coats the LED and, for example, is configured to convert the primary light, or blue light, into light with different spectral characteristics (specifically, into near-infrared light). Typically, a phosphor LED can be packaged in a housing or unpackaged. Thus, the LED and the at least one luminescent material for photoconverting the primary light generated by the light-emitting diode can be housed in a common housing. Alternatively, however, the LED may also be an unpackaged or bare LED, which may be fully or partially covered with luminescent material, such as by providing one or more layers of luminescent material on the LED die.A phosphor LED may typically form the emitter or light source itself.

[0052] In a light source (particularly a phosphor LED), at least one luminescent material can be positioned relative to a light-emitting diode (LED) such that heat can be transferred from the diode to the luminescent material. More specifically, the luminescent material can be positioned such that heat can be transferred via one or both of thermal radiation and thermal conduction (more preferably thermal conduction). Thus, by way of example, the luminescent material can be in thermal and / or physical contact with the light-emitting diode. By way of example, the luminescent material can form one or more coatings or layers that are in contact with or in close proximity to the light-emitting diode, such as contact with one or more of the semiconductor materials of the light-emitting diode. Thus, the temperature of the luminescent material and the temperature of the light-emitting diode can generally be coupled.

[0053] The at least one luminescent material can specifically form at least one layer. In general, various alternative approaches to positioning the luminescent material relative to the LED are possible, which can be used individually or in combination. First, the luminescent material (e.g., at least one layer of luminescent material, such as a phosphor) can be positioned directly on the LED, also referred to as "direct attachment," e.g., with no material between the LED and the luminescent material, or with one or more transparent materials between them, such as one or more transparent materials (particularly transparent to the primary light) between the LED and the luminescent material. Thus, by way of example, a coating of luminescent material can be placed directly or indirectly on the LED. Additionally or alternatively, by way of example, the luminescent material can form at least one converter, such as at least one converter disk, which can be placed on top of the LED, for example, by attaching the converter to the LED with an adhesive. Additionally or alternatively, the luminescent material can be remotely positioned, such that the primary light from the LED must traverse an intermediate light path before reaching the luminescent material. This placement can also be referred to as "remote placement" or "remote phosphor." Similarly, by way of example, a remotely positioned luminescent material can form a solid or converter, such as a disk or converter disk. Furthermore, in the case of remote placement, the luminescent material can also be a coating. In particular, a light-transmitting object (e.g., a thin glass substrate, a module window) comprising and / or made of glass or plastic can be coated with a phosphor. Alternatively, a reflective surface can be coated with a phosphor. This can be a flat or rough reflector, which can comprise and / or be made of a substrate of a highly reflective 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, gratings, reflectors, apertures, or combinations thereof, can be placed in the intermediate light path. Specifically, an optical system with imaging properties can be placed in the intermediate light path, between the LED and the luminescent material. Thus, for example, the primary light can be focused or concentrated onto the converter.

[0054] The spectrometer device further comprises at least one detector for detecting detection light from the object and generating at least one detector signal.

[0055] As used herein, the verb "detect" is a broad term and is to be given its ordinary and conventional meaning to those skilled in the art and is not limited to a special or customized meaning. The term may specifically refer to, but is not limited to, the process of at least one of qualitatively and / or quantitatively determining, measuring, and monitoring at least one parameter (such as at least one of a physical parameter, a chemical parameter, and a biological parameter). Specifically, a physical parameter may be or may include an electrical parameter. Therefore, as used herein, the term "detector" is a broad term and is to be given its ordinary and conventional meaning to those skilled in the art and is not limited to a special or customized meaning. The term may specifically refer to, but is not limited to, any device configured to detect, i.e., to at least one of qualitatively and / or quantitatively determine, measure, and monitor at least one parameter (such as at least one of a physical parameter, a chemical parameter, and a biological parameter). A detector may be configured to generate at least one detector signal, more specifically at least one electrical detector signal, such as an analog and / or digital detector signal, that provides information about the at least one parameter measured by the detector. The detector signal may specifically include at least one detector current indicative of an accumulated photocurrent from the detector, and more specifically, at least one detector current for each pixel of the detector. The detector signal can be provided by the detector directly or indirectly to the evaluation unit, so that the detector and the evaluation unit can be directly or indirectly connected. The detector signal can be used as a "raw" detector signal and / or can be processed or preprocessed (e.g., by filtering, etc.) before further use. Thus, the detector can include at least one processing device and / or at least one preprocessing device, such as at least one of an amplifier, an analog / digital converter, an electrical filter, and a Fourier transform.

[0056] In this example, the detector is configured to detect light propagating from the object to the spectrometer device, or more specifically, to a detector of the spectrometer device. According to the aforementioned nomenclature, this light is referred to as "detection light." Specifically, the detector may be 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 irradiating at least one sensitive region of the detector. More specifically, the optical detector may include at least one photosensor and / or at least one optical sensor, such as at least one of a photodiode, a photocell, a photoresistor, a phototransistor, a thermopile sensor, a photoacoustic sensor, a pyroelectric sensor, a photomultiplier, and a bolometer. The detector may be configured to generate at least one detector signal, more specifically at least one electrical detector signal in the aforementioned sense, that provides information about at least one optical parameter, such as the power and / or intensity of light irradiating the detector or a sensitive region of the detector.

[0057] The detector may include a single optically sensitive element or region or a plurality of optically sensitive elements or regions (also referred to as "photosensitive elements"). In particular, the detector may be or may include at least one detector array (more particularly an array of photosensitive elements), as will be further detailed below. Each photosensitive element may include at least a photosensitive region, which may be adapted to generate an electrical signal depending on the intensity of incident light, wherein the electrical signal may in particular be provided to an evaluation unit, as will be further detailed below.

[0058] The photosensitive area comprised by each optically sensitive element may in particular be a single, homogeneous photosensitive area configured to receive incident light impinging on the respective optically sensitive element. However, other arrangements of the optically sensitive elements are also conceivable.

[0059] The array of optically sensitive elements can be designed to generate a detector signal, preferably an electronic signal, which is associated with the intensity of the incident light impinging on the individual optically sensitive elements. The detector signal can be an analog signal and / or a digital signal. Accordingly, the electronic signals of adjacent pixelated sensors can be generated simultaneously or in a temporally consecutive manner. For example, during a row scan or line scan, a series of electronic signals can be generated corresponding to a series of individual optically sensitive elements arranged in a row. In addition, these individual optically sensitive elements can preferably be active pixel sensors, which can be suitable for amplifying the electronic signals before providing them to the evaluation unit. For this purpose, the detector can include one or more signal processing devices, such as one or more filters and / or analog-to-digital converters, for processing and / or preprocessing the electronic signals.

[0060] In the case where the detector comprises an array of optically sensitive elements, the detector can, by way of example, be selected from any known pixelated sensor, in particular, from pixelated organic camera elements, preferably pixelated organic camera chips, or from pixelated inorganic camera elements, preferably pixelated inorganic camera chips, more preferably from CCD chips or CMOS chips, which are the types commonly used in various cameras today. Alternatively, the detector can generally be or include a photoconductor, in particular an inorganic photoconductor, especially PbS, PbSe, Ge, InGaAs, extended InGaAs, InSb, or HgCdTe. As another alternative, the detector can include at least one of a pyroelectric element, a bolometer element, or a thermopile detector element. Thus, a camera chip having a matrix of 1 × N pixels or M × N pixels can be used, where, by way of example, M can be <10 and N can be in the range of 1 to 50, preferably 2 to 20, and more preferably 5 to 10. Furthermore, a monochrome camera element, preferably a monochrome camera chip, can be used, wherein the monochrome camera element can be selected differently for each optically sensitive element, in particular depending on the wavelength that varies across a range of optical sensors.

[0061] Hence, the array may be adapted to provide a plurality of electrical signals which may be generated by the photosensitive areas of the optically sensitive elements comprised by the array.The electrical signals provided by the array of the spectrometer device may be forwarded to an evaluation unit.

[0062] The spectrometer device further comprises at least one drive unit for electrically driving the light source.

[0063] As used herein, the term "driver" is a broad term and is to be given its ordinary and conventional meaning to those skilled in the art and is not limited to a special or customized meaning. The term may specifically refer to, but is not limited to, the process of providing one or both of at least one control parameter and / or electrical power to another device. Therefore, as used herein, the term "drive unit" is a broad term and is to be given its ordinary and conventional meaning to those skilled in the art and is not limited to a special or customized meaning. The term may specifically refer to, but is not limited to, any device or combination of devices configured to provide one or both of at least one control parameter and / or electrical power to another device (e.g., in this example, at least one light source). A driver unit may specifically be configured to control one or more electrical parameters of the electrical power provided to a light source (specifically, to at least one light-emitting diode). As an example, a driver unit may be configured to provide current to an LED, specifically to control the current through the LED. For example, the driver unit may be configured to adapt the voltage provided to the LED to achieve a specific current through the LED. The driver unit may include one or more of a current source and a voltage source. Specifically, the driving unit may include at least one current source for providing at least one predetermined current to the LED, wherein the current source may be specifically configured to adjust or control the voltage applied to the LED to generate the predetermined current. As an example, the driving unit may include one or more electrical components (such as an integrated circuit) for driving the light source. The driving unit may be fully or partially integrated into the light source, or may be separate from the light source.

[0064] The spectrometer device includes at least one multi-channel readout integrated circuit. Each channel of the multi-channel readout integrated circuit includes at least one buffered direct injection (BDI) circuit. The BDI circuit is configured to read out a detector signal and generate at least one information item regarding an electrically measurable quantity required to drive a light source. The multi-channel readout integrated circuit includes at least one multi-channel readout application-specific integrated circuit (ASIC) configured to synchronously sample the detector signal and the information item regarding the electrically measurable quantity required to drive the light source.

[0065] As used herein, the term "readout" (also referred to as "read") is a broad term and is to be given its ordinary and customary meaning to one of ordinary skill in the art and is not limited to a special or customized meaning. The term may specifically refer to, but is not limited to, the act or process of quantifying and / or processing at least one physical property and / or a change in at least one physical property detected by at least one device (specifically, at least one component of a spectrometer device).

[0066] As used herein, the term "integrated circuit" (IC) is a broad term and is to be given its ordinary and customary meaning for those skilled in the art and is not limited to a special or customary meaning. The term may specifically refer to, but is not limited to, a set of electronic circuits on a chip. A chip may include at least one substrate made of semiconductor material, particularly at least one substrate made of silicon. As used herein, the term "readout integrated circuit" (ROIC) is a broad term and is to be given its ordinary and customary meaning for those skilled in the art and is not limited to a special or customary meaning. The term may specifically refer to, but is not limited to, an integrated circuit configured to read at least one component of a spectrometer device. For example, an ROIC may be configured to read a detector, where reading the detector may include accumulating photocurrent from each pixel of the detector to generate a detector signal and transmitting the detector signal to at least one output for further evaluation. Alternatively, the ROIC may be configured to generate information about an electrically measurable quantity required to drive a light source. The ROIC may have at least one channel for reading the detector (particularly, at least one channel for each pixel of the detector) and at least one channel for generating information about the electrically measurable quantity required to drive the light source, as will be further described below.

[0067] The readout integrated circuit may specifically be an analog integrated circuit, i.e. an integrated circuit comprising a set of circuits having active elements such as transistors and / or passive elements such as capacitors, resistors and / or inductors configured for processing a continuous signal, in particular a continuous analog signal.

[0068] A multi-channel readout integrated circuit may include at least two channels, such as at least one channel for reading out a detector signal and at least one channel for generating information about an electrically measurable quantity required to drive a light source. Therefore, a readout integrated circuit including at least two channels may also be referred to as a "multi-channel readout integrated circuit." As used herein, the term "channel" is a broad term and is to be given its ordinary and customary meaning to those skilled in the art and is not limited to a specific or customary meaning. The term may specifically refer to, but is not limited to, a circuit or group of circuits associated with at least one component of a spectrometer device. Specifically, a multi-channel readout integrated circuit may include at least one channel associated with a detector, the channel being specifically configured to read out a detector signal generated by the detector. Alternatively, the multi-channel readout integrated circuit may include at least one additional channel associated with another component (such as a resistor), as will be described in further detail below, the channel being specifically configured to generate information about an electrically measurable quantity required to drive a light source. As described above, the detector may include a plurality of photosensitive elements. In this case, the multi-channel readout integrated circuit may include at least one channel associated with each photosensitive element and being specifically configured to read out the detector signal of the associated photosensitive element.

[0069] As outlined above, each channel includes at least one BDI circuit. As used herein, the term "buffered direct injection circuit" (also referred to as "BDI circuit") is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not limited to a special or customized meaning. The term may specifically refer to, but is not limited to, an electronic device that includes at least one circuit configured to provide a buffering function. In particular, the BDI circuit may include a single circuit or a group of circuits, wherein at least one circuit may include at least one feedback circuit, in particular at least one feedback circuit configured to reduce the input impedance of an input signal to the BDI circuit. To this end, the BDI circuit may include at least one buffer amplifier, such as at least one voltage buffer and / or at least one current buffer. The BDI circuit may specifically be implemented as an ASIC having multiple channels for reading out the detectors in parallel for the multiple channels and generating information items about electrically measurable quantities required to drive the light source.

[0070] As used herein, the term "electrically measurable quantity" is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not limited to a special or customized meaning. The term may specifically refer to, but is not limited to, any parameter required to drive a light source and that can be electrically measured. Thus, the term "information item about an electrically measurable quantity" may refer to any numerical indication that quantifies the electrically measurable quantity. For example, an information item about an electrically measurable quantity required to drive a light source may include at least one information item selected from the group consisting of: a forward voltage at the light source; a voltage drop at the light source; a current at the light source; an electrical power input to the light source; a resistance of the light source; or an impedance of the light source.

[0071] As used herein, the term "application-specific integrated circuit (ASIC)" is a broad term and is to be given its ordinary and customary meaning to those skilled in the art and is not limited to a special or customary meaning. The term may specifically, but is not limited to, an integrated circuit configured for a specific purpose. Specifically, in the context of the present invention, the ASIC is configured to simultaneously sample a detector signal and an item of information regarding an electrically measurable quantity required to drive a light source. Thus, a specific use of the ASIC may be to simultaneously sample a detector signal and an item of information regarding an electrically measurable quantity required to drive a light source.

[0072] As used herein, the term "sampling" is a broad term and is to be given its ordinary and customary meaning to one of ordinary skill in the art and is not limited to a special or customized meaning. The term may specifically refer to, but is not limited to, the process of obtaining a measurement value from a continuous-time signal. In particular, sampling may include obtaining a measurement value, such as a detector signal and / or an item of information about an electrically measurable quantity required to drive a light source, from a continuous-time signal provided to a BDI circuit, in particular, to an ASIC. The continuous-time signal may include an electrical signal from a detector, such as a photocurrent and / or photovoltage dependent on the intensity of light incident on the detector, and / or an electrical signal of an electrically measurable quantity required to drive a light source.

[0073] As used herein, the term "synchronous" is a broad term and is to be given its ordinary and conventional meaning to one of ordinary skill in the art and is not limited to a special or customized meaning. The term may specifically refer to, but is not limited to, the characteristic of two or more processes being performed in a manner that at least partially overlaps in time. Specifically, performing two or more processes synchronously may include starting and completing the two or more processes at the same time, or alternatively, starting at least one process first and then at least one other process, wherein, further, the at least one other process may be started before the previously started process is completed. Synchronously sampling the detector signal and the information item about the electrically measurable quantity required to drive the light source may include reading the detector signal and generating the information item about the electrically measurable quantity required to drive the light source in a manner that at least partially overlaps in time, specifically simultaneously. For example, synchronously sampling the detector signal and the information item about the electrically measurable quantity required to drive the light source may include reading the detector signal in parallel and generating the information item about the electrically measurable quantity required to drive the light source.

[0074] A multi-channel readout application-specific integrated circuit (ASIC) may include at least one skimming circuit configured to skim current at a detector. As used herein, the term "skimming circuit" is a broad term and is to be given its ordinary and customary meaning to those skilled in the art and is not limited to a special or customary meaning. The term may specifically, but is not limited to, refer to a circuit configured for current skimming, specifically, for removing a portion of the current flowing in another circuit. Specifically, the skimming circuit may be configured to skim current at a detector, i.e., the detector current. As outlined above, the detector signal may specifically include a detector current indicative of the accumulated photocurrent from the detector. Thus, the skimming circuit may act as a current sink, specifically, a current sink of the detector current. The skimming circuit may be included in at least one channel of the multi-channel readout integrated circuit, specifically, the multi-channel readout application-specific integrated circuit (ASIC), configured to read out the detector signal. The skimming circuit may be optional. For example, if the light source includes an LED, the skimming circuit may not be required. In this case, the input voltage of the BDI circuit may be within the range of the forward LED voltage, and therefore, skimming may not be required. However, in other cases, such as other light sources where the BDI input voltage may be lower than the voltage applied to the light source (e.g., 0 V), it may be advantageous to use a skimming circuit in the ASIC to remove the DC component of the voltage applied to the light source. The skimming circuit may specifically include at least one programmable current sink, which may include one or more transistors, specifically a plurality of transistors. The transistors may be of equal size and may be configured in parallel, specifically with equal weighting when programmed, or alternatively, the transistors may be of double size and configured in series, specifically with binary weighting when programmed.

[0075] An exemplary channel of a multi-channel readout integrated circuit includes a BDI circuit and can be configured to read out a detector signal. The input of the BDI circuit can be connected to the output of the detector, specifically to the output of a pixel of the detector. By applying a bias voltage to the BDI circuit , the voltage applied to the detector can be kept constant. The multi-channel readout integrated circuit can additionally include an analog-to-digital converter (ADC). Any change in the detector resistance due to illumination can result in an increase in current flow, which can be digitized by the ADC. Optionally, the ROIC, and in particular the multi-channel readout application specific integrated circuit, can include at least one skimming circuit configured to skim the current at the detector, in particular to remove any offset in the signal (particularly where the light source may include a light source other than an LED).

[0076] Additionally or alternatively, an exemplary channel of the multi-channel readout integrated circuit includes a BDI circuit and can be configured to generate an item of information about an electrically measurable quantity required to drive a light source. As an example, the light source can include an LED. The spectrometer device can further include at least one resistor electrically connecting an anode of the LED to the ROIC. For example, the resistor can have a to range of resistance, specifically . Additionally, the spectrometer device may include a shunt resistor. In this example, the spectrometer device may include at least two resistors, wherein the two or more resistors may be implemented in a similar manner relative to each other, or alternatively implemented in a different manner relative to each other. Each side of the shunt resistor may be electrically connected to the multi-channel readout integrated circuit via one of the resistors. Thus, both the voltage drop at the shunt resistor and the current through the light source may be determinable. As an example, the shunt resistor may have a to range of resistance, specifically .

[0077] The spectrometer device comprises at least one evaluation unit for evaluating at least one detector signal generated by the detector and for deriving spectroscopic information about the object from the detector signal. The evaluation unit is configured to take into account information items about electrically measurable quantities required to drive the light source when deriving the spectroscopic information from the detector signal.

[0078] As used herein, the term "evaluation" is a broad term and is to be given its ordinary and conventional meaning to a person of ordinary skill in the art and is not limited to a special or customized meaning. The term may specifically refer to, but is not limited to, a process of processing at least one first information item so as to generate at least one second information item therefrom. Thus, as used herein, the term "evaluation unit" is a broad term and is to be given its ordinary and conventional meaning to a person of ordinary skill in the art and is not limited to a special or customized meaning. The term may specifically refer to, but is not limited to, any device or combination of devices configured to evaluate or process at least one first information item so as to generate at least one second information item thereof. Thus, in particular, the evaluation unit may be configured to process at least one input signal and generate at least one output signal thereof. As an example, the at least one input signal may include at least one detector signal provided directly or indirectly by at least one detector, and further at least one signal provided directly or indirectly by a multi-channel readout integrated circuit, the signal specifically including at least one information item about at least one electrically measurable quantity.

[0079] By way of example, the evaluation unit may be or may include one or more integrated circuits (such as one or more application-specific integrated circuits (ASICs)) and / or one or more data processing devices (such as one or more computers, digital signal processors (DSPs), and field-programmable gate arrays (FPGAs)), preferably one or more microcomputers and / or microcontrollers. Additional components may be included, such as one or more preprocessing devices and / or data acquisition devices, such as one or more devices for receiving and / or preprocessing detector signals, such as one or more 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, such as one or more wireless interfaces and / or one or more wired interfaces.

[0080] The evaluation unit can be adapted to execute at least one computer program, such as at least one computer program that performs or supports the information item generation step. For example, one or more algorithms can be implemented that, using at least one detector signal and at least one information item about at least one electrically measurable quantity as input variables, can perform a predetermined transformation to obtain spectroscopic information about the object, such as a corrected spectrum and / or at least one item of spectroscopic information describing at least one characteristic of the object. To this end, the evaluation unit can specifically include at least one data processing device (also referred to as a processor, in particular an electronic data processing device) designed to generate the desired information by evaluating the detector signal and the information item about the at least one electrically measurable quantity. The evaluation unit can use any desired process to generate the desired information, such as calculation and / or using at least one stored and / or known relationship. The evaluation unit can specifically be configured to perform at least one digital signal processing (DSP) technique, in particular at least one Fourier transform, on the primary detector signal or any secondary detector signals derived therefrom. Additionally or alternatively, the evaluation unit may be configured to perform one or more additional digital signal processing techniques on the primary detector signal or any secondary detector signal derived therefrom, such as windowing, filtering, the Goertzel algorithm, cross-correlation, and autocorrelation. In addition to the detector signal and information about at least one electrically measurable quantity, one or more additional parameters and / or information items may also influence the relationship. The relationship may be determined or determinable by empirical, analytical, or semi-empirical methods. As an example, the relationship may include at least one of a model or calibration curve, at least one set of calibration curves, at least one function, or a combination of the aforementioned possibilities. One or more calibration curves may be stored, for example, in a data storage device and / or table, in the form of a set of values ​​and their associated function values. Alternatively or in addition, however, at least one calibration curve may also be stored, for example, in parameterized form and / or as a functional equation. A separate relationship may be used to process the detector signal into information items. Alternatively, at least one combined relationship for processing the detector signal is feasible. Various possibilities are conceivable, and these possibilities may also be combined.

[0081] The evaluation unit can be specifically configured, for example, through software programming, to determine at least one correction based on information about at least one electrically measurable quantity. Thus, by way of example, the evaluation unit can be configured to determine a spectrum, such as a spectrum indicating a wavelength-dependent photometric or radiometric parameter, from at least one detector signal provided by a detector. The spectrum can be corrected by applying at least one correction function (e.g., a correction factor, such as a wavelength-dependent correction factor of the correction function) to the spectrum, thereby generating a corrected spectrum. Thus, by way of example, the correction factor can specifically be or include at least one correction factor that is a function of at least the wavelength of the detection light and the at least one electrically measurable quantity. By way of example, the detector signal can provide a signal that is a function of the wavelength of the detection light, wherein, by using the correction factor, each function value of the detector signal can be multiplied by a corresponding correction factor determined from the at least one electrically measurable quantity.

[0082] By way of example, the detector signal may include multiple detector signals that are at least a function of the wavelength of the detection light and, optionally, also a function of time, particularly for time-dependent detector signals. These multiple detector signals may form a spectrum, including options for digital or analog spectra. Thus, by way of example, each detector signal may summarize information from a predetermined spectral range defined by the detector's spectral resolution. As outlined above, the detector may include multiple photosensors, each sensitive to and / or exposed to a different portion of the detection light spectrum within a different spectral range. All detector signals from the photosensors may form the detector signal, or, by way of example, collectively define the spectral information, a portion thereof, or a precursor thereof. Since the spectral sensitivity range of each photosensor may be known, the intensity of the detection light as a function of the detection wavelength can be derived from this detector signal by combining data pairs from the photosensors, each data pair comprising a corresponding signal from the photosensor and the sensitivity wavelength. Each of the corresponding signals of the photosensors may be corrected using a corresponding correction factor for the corresponding wavelength, wherein the correction factor, as a function of at least one electrically measurable quantity, particularly the forward voltage, is provided by the evaluation unit. However, it should be noted that other ways of generating spectral information are also possible, such as by sequentially exposing the same detector to different spectral portions of the detection light, for example by using a scannable wavelength selective element. Correction of these sequentially determined spectra can be performed in a similar manner by using a correction factor as a function of wavelength and by correcting the spectra accordingly.

[0083] The spectrometer device may further include at least one resistor electrically connecting the light source to the multi-channel readout integrated circuit. Specifically, when the light source includes an LED, the resistor may electrically connect the anode of the LED to the ROIC. Furthermore, the spectrometer device may include at least two resistors and at least one shunt resistor. Each side of the shunt resistor may be electrically connected to the multi-channel readout integrated circuit via at least one of the resistors. Thus, the voltage drop across the shunt resistor can be determined, and the current through the light source can be determined. The resistor and / or the shunt resistor may have a temperature coefficient of less than 1000 ppm / K, specifically less than 100 ppm / K, more specifically less than 50 ppm / K, and even more specifically less than 10 ppm / K.

[0084] As outlined above, the detector can include a plurality of photosensitive elements, in particular an array of photosensitive elements, wherein each photosensitive element can be configured to generate at least one detector signal. The evaluation unit can be configured to individually consider, for each of the detector signals of the photosensitive elements, an item of information about the electrically measurable quantity required to drive the light source, and to combine the detector signals to obtain spectroscopic information. In particular, the spectrometer device can be configured such that the photosensitive elements are sensitive to different spectral ranges of the light from the object. For example, the spectrometer device can include at least one wavelength-selective element arranged in the beam path of the detection light. The wavelength-selective element can be configured such that each photosensitive element is exposed to a separate spectral range of the detection light from the object.

[0085] Additionally or alternatively, the detector may comprise a single detector, and the light source may comprise a plurality of light sources having different spectral ranges. Each of the light sources may be configured to generate illumination light for illuminating an object within a specific spectral range. The detector may be configured to detect the detection light from the object, specifically including reflected illumination light within different spectral ranges from the plurality of light sources, and to generate at least one time-correlated detector signal. The evaluation unit may be configured to evaluate the time-correlated detector signals using frequency multiplexing, specifically such that at least one detector signal for each of the different spectral ranges can be derived from the time-correlated detector signals. The detector signal for each of the different spectral ranges can be used to obtain spectroscopic information about the object. Specifically, the evaluation unit may be configured to separately consider, for each of the detector signals, an information item regarding an electrically measurable quantity required to drive the light source, and to combine the detector signals to obtain the spectroscopic information. Additionally or alternatively, both multiple photosensors and multiple light sources as described above may be used. In both cases, the multi-channel readout circuitry may allow for synchronous sampling of the detector signal and the information item regarding the electrically measurable quantity required to drive the light source.

[0086] The spectrometer device may include at least one wavelength selection element. The wavelength selection element may include at least one of a wavelength selection element arranged in the beam path of the illumination light and a wavelength selection element arranged in the beam path of the detection light. The wavelength selection element may be selected from the group consisting of a tunable wavelength selection element and a wavelength selection element with a fixed transmission spectrum. The wavelength selection element with a fixed transmission spectrum may include at least one filter element, specifically at least one absorption filter element, more specifically a bandpass filter element. The tunable wavelength selection element may include at least one tunable interferometer, specifically at least one of a MEMS Fabry-Perot interferometer and a MEMS Michelson interferometer.

[0087] In another aspect of the invention, a method of obtaining spectroscopic information about at least one object by using a spectrometer device is disclosed. With regard to possible embodiments of the spectrometer device and definitions of terms, reference is made to the above description of the spectrometer device.

[0088] The method comprises the following steps, which may be performed in a given order. However, different orders are also possible. In particular, one, more than one, or even all of the method steps may be performed once or repeatedly. Furthermore, these method steps may be performed sequentially, or alternatively, one or more method steps may be performed in a timely overlapping manner or even in parallel and / or in a combined manner. The method may further comprise additional method steps not listed.

[0089] The method includes:

[0090] a. by using at least one driving unit to electrically drive at least one light source;

[0091] b. illuminating the object with illumination light generated by the light source;

[0092] c. generating at least one detector signal by detecting detection light from the object using at least one detector;

[0093] d. generating at least one item of information about an electrically measurable quantity required to drive the light source by using at least one multi-channel readout integrated circuit, wherein each channel of the multi-channel readout integrated circuit comprises at least one buffered direct injection (BDI) circuit, wherein the BDI circuit is configured to read out the detector signal, wherein the BDI circuit is configured to generate the at least one item of information about the electrically measurable quantity required to drive the light source, wherein the multi-channel readout integrated circuit comprises at least one multi-channel readout application specific integrated circuit (ASIC), the at least one multi-channel readout application specific integrated circuit being configured to synchronously sample the detector signal and the item of information about the electrically measurable quantity required to drive the light source; and

[0094] e. deriving the spectroscopic information about the object from the detector signal by evaluating the at least one detector signal generated by the detector using at least one evaluation unit and taking into account the item of information about the electrically measurable quantity required to drive the light source.

[0095] In particular, in this method, a spectrometer device according to the present invention, such as according to any of the embodiments disclosed above and / or any of the embodiments disclosed in further detail below, may be used.

[0096] Steps c. and d. can be performed in a temporally overlapping manner, in particular in parallel.

[0097] The method can be performed on-site, online. As used herein, the term "online" is a broad term and is to be given its ordinary and customary meaning for those skilled in the art and is not limited to a specific or customary meaning. The term may specifically refer to, but is not limited to, the characteristic that a process is performed while another process is ongoing (e.g., during the other process), preferably without requiring a separate user start or initiation. Thus, in particular, calibration of the detector signal using at least one information item about an electrically measurable quantity can be performed as an online calibration or online correction during the acquisition of spectroscopic information about at least one object, without requiring a separate calibration process.

[0098] Furthermore, in step e., at least one correction can be determined based on the information item about the electrically measurable quantity required to drive the light source, wherein the at least one detector signal can further be corrected using the correction. The correction can specifically include at least one temperature correction. The temperature correction can depend at least in part on the information item about the electrically measurable quantity required to drive the light source. The correction can include multiplying the at least one detector signal by at least one correction factor. The corrected detector signal can be used to obtain the spectroscopic information.

[0099] As used herein, the term "calibration" is a broad term and is to be given its ordinary and customary meaning for those of ordinary skill in the art and is not limited to a specific or customary meaning. The term may specifically, but not limited to, refer to a modification or process of modifying at least one item of interest based on one or more information items indicative of parameters known to have an impact on the item of interest. Thus, a measured spectrum may be corrected such that the corrected spectrum corresponds to a spectrum under precisely known conditions or standardized conditions (e.g., at a specific temperature and / or at a predetermined electrically measurable quantity). As an example, correction may include modifying the measured spectrum included in the detector signal to correspond to standardized conditions, such as at a predetermined electrically measurable quantity required to drive a light source and / or at a predetermined temperature. Thus, step e. may include correction, in which the measured spectrum derived from the detector signal is modified to correspond to a corrected spectrum, specifically a corrected spectrum that may have been obtained under predetermined standard conditions (e.g., at a predetermined electrically measurable quantity required to drive a light source and / or at a predetermined temperature). Standardized conditions may be defined using appropriate conditions, such as by using room temperature as the predetermined temperature and / or using a specific measurable quantity required to drive a light source measured at room temperature and at a predetermined forward current. However, other standard conditions are also possible. Thus, the corrected spectrum can be compared with a reference spectrum determined under precisely known conditions or standardized conditions.

[0100] To determine the correction factor, specifically the correction function, one or more calibration measurements can be performed. Thus, the calibration can be based on one or more calibration measurements. For example, these calibration measurements can determine at least one detector signal as a function of the electrically measurable quantity (and, further, optionally, also as a function of the detection wavelength). As outlined above, at least one condition can be determined as a standard condition, for example, at least one specific electrically measurable quantity required to drive the light source. For example, the electrically measurable quantity measured at room temperature can be predetermined, defining standard conditions for each wavelength. By determining the ratio of the detector signal measured for the specific electrically measurable quantity to the detector signal measured for a predetermined standard electrically measurable quantity, a correction factor can be determined for each wavelength. Thus, specifically, when the information item about the electrically measurable quantity indicates that the electrically measurable quantity deviates from the standard electrically measurable quantity, the correction factor can be selected such that the corrected detector signal corresponds to the detector signal that would have been measured under conditions identical to the predetermined standard conditions (e.g., room temperature). Additionally or alternatively, the temperature can be varied in a targeted manner, for example, to set or adjust the temperature to two or more target temperatures. Specifically, the standard conditions may include a set of two or more predefined target temperatures and / or a set of corresponding electrically measurable quantities. For each of these temperatures, the electrically measurable quantity and the detector signal may be measured, for example, for each wavelength. The correction factor may then be determined as described above.

[0101] The correction can specifically be based on a model that describes the functional relationship between the spectral characteristics of the light source and the electrically measurable quantity and / or temperature. The model can be an empirical model, a semi-empirical model, or a theoretical model. Thus, as an example, and as will be described in further detail below, the effect of changes in the electrically measurable quantity required to drive the light source on the spectrum can be measured in one or more calibration measurements, for example by using a standardized object or reference object and measuring the spectrum as a function of the electrically measurable quantity. The correction can then be determined, for example, by using a specific electrically measurable quantity as a standard and correcting the spectra determined for other electrically measurable quantities to correspond to the standardized spectrum.

[0102] At least one model describing the functional relationship between modifications to the spectrum and / or spectroscopic information about the object and the electrically measurable quantity and / or describing the functional relationship between corrections required to correct the spectrum and / or spectroscopic information about the object and the electrically measurable quantity can be predetermined and, as an example, can be stored in at least one data storage device of the spectrometer device.

[0103] As further outlined above, the evaluation unit can be configured to correct at least one detector signal by using a correction. Thus, by way of example, the evaluation unit can be configured, for example through software programming, to directly or indirectly transform the detector signal (e.g., the spectrum derived therefrom) into a corrected detector signal, for example, into a corrected spectrum. By way of example and as further outlined above, the correction can specifically include multiplying at least one detector signal (i.e., the "raw" detector signal or a secondary detector signal derived therefrom, for example, a spectrum generated by using the detector signal) by at least one correction factor. Thus, a correction of the spectrum can be performed that takes into account the electrically measurable quantities required to drive the light source as correction parameters. The evaluation unit can specifically be configured to use the corrected detector signal to derive spectroscopic information.

[0104] As an example, the detector can be configured to generate detector signals for at least one spectral range of light from the object (specifically, for at least two different spectral ranges), specifically at least one of sequentially and simultaneously. For example, as outlined above, the detector can include an array of photosensitive elements, each of which can be sensitive to and / or exposed to light within a different spectral range. The evaluation unit can be configured to individually correct the detector signals for the different spectral ranges and to combine the individually corrected detector signals to obtain spectroscopic information. Thus, the individually corrected detector signals can be combined, for example, to generate a corrected spectrum.

[0105] Thus, in general, the detector may comprise an array of photosensitive elements, wherein each photosensitive element may be configured to generate at least one detector signal. The evaluation unit may generally be configured to individually correct each detector signal and to combine the detector signals to obtain the spectroscopic information. Thus, in particular, if each photosensitive element is sensitive to light in a different spectral range and / or is exposed to light in a different spectral range, for example via one or more suitable filters in the beam path of the detection light, the electrically measurable quantity may be individually corrected for the influence of the correction parameter and / or the influence of temperature for each photosensitive element.

[0106] The method, specifically at least step e. of the method, may be computer-implemented. As used herein, the term "computer-implemented" is a broad term and is to be given its ordinary and customary meaning for persons of ordinary skill in the art and is not limited to a specific or customary meaning. The term may specifically, but not limited to, refer to a process implemented in whole or in part using a data processing device (e.g., a data processing device comprising at least one processing unit). The method, specifically step e., may be computer-implemented, or at least computer-controlled or computer-assisted, using an evaluation unit of a spectrometer apparatus.

[0107] In another aspect of the present invention, a computer program is disclosed, comprising instructions which, when executed by a spectrometer device according to the present invention (such as according to any of the embodiments disclosed above and / or according to any of the embodiments disclosed in further detail below), cause the spectrometer device to perform a method according to the present invention (such as according to any of the embodiments disclosed above and / or according to any of the embodiments disclosed in further detail below).

[0108] Similarly, a computer-readable storage medium, in particular a non-transitory computer-readable medium, is disclosed, comprising instructions which, when executed by a spectrometer device according to the present invention (such as according to any of the embodiments disclosed above and / or according to any of the embodiments disclosed in further detail below), cause the spectrometer device to perform a method according to the present invention (such as according to any of the embodiments disclosed above and / or according to any of the embodiments disclosed in further detail below).

[0109] As used herein, the terms "computer-readable data carrier," "computer-readable storage medium," and "non-transitory computer-readable medium" are broad terms and are to be given their ordinary and customary meanings to those skilled in the art and are not limited to special or customized meanings. These terms may specifically refer to, but are not limited to, data storage devices, particularly non-transitory data storage devices, such as hardware storage media having computer-executable instructions stored thereon. A computer-readable data carrier or storage medium or computer-readable medium may specifically be or include a storage medium such as a random access memory (RAM) and / or a read-only memory (ROM).

[0110] In one or more of the above-described embodiments and / or in one or more of the embodiments described in further detail below, the spectrometer device and method according to the present invention offer numerous advantages over known devices and methods of similar types. Specifically, the spectrometer device and method for obtaining spectroscopic information about at least one object require minimal hardware effort to correct for external and / or internal influences (such as temperature) on the spectrometer device. The spectrometer device can provide a measurement device that allows for high-resolution measurement of various physical quantities using a BDI circuit with minimal additional hardware adjustments. One or more BDI circuits can be used to read out a detector, specifically one or more photoconductive detectors, and generate information about electrically measurable quantities required to drive a light source. Such a multi-channel readout ASIC can allow for simultaneous sampling of optical and electrical signals. Therefore, for each optical measurement of a detector, a corresponding measurement of other components can be performed and used for compensation. The ROIC can specifically include multiple channels, each of which includes one or more BDI circuits. By applying a bias voltage to the BDI circuit, , the voltage applied to the detector can be kept constant. The current generated by the applied voltage can be skimmed using current skimming to remove any offset in the signal. Any change in the detector resistance due to illumination can result in an increased current flow, which can be digitized using an analog-to-digital converter (ADC) with relatively high time and voltage resolution. The bias voltage can be adjusted depending on the measurement task.

[0111] In one example, the light source may include an LED. If the current at the LED can be regulated to a constant current , specifically so that the LED is maintained at a constant level of power output, the voltage variations are minimal within the selected current range. For example, the current at the LED can be selected so that the LED can have a forward voltage of 2.7 V to 2.9 V, depending on the temperature. In the ROIC, the input voltage of the BDI can be set to a stable 2.6 V. Therefore, by connecting a resistor, specifically a resistor with a low temperature coefficient, between the anode of the LED and the input of the ROIC, it is possible to analyze with high precision the information items about the electrically measurable quantities required to drive the light source in the region of interest of approximately 0.1 V to 0.3 V. However, other input voltages may also be feasible for other light sources. Thus, the BDI can be used as an offset removal circuit.

[0112] Specifically, can be applied to the resistor, resulting in a current that can be digitized. Therefore, only the change in the LED forward voltage due to temperature changes can be determined with high accuracy. As an example, the temperature can change from 20°C to 30°C. The voltage drop across the resistor can be determined according to the following formula

[0113]

[0114]

[0115]

[0116] By using The ROIC can be configured to have 24-bit resolution over this voltage and current range. and voltage and current resolution.

[0117] Even though the absolute accuracy of the measured voltage may degrade due to various disturbances (e.g. tolerance of the BDI voltage, resistor tolerance, etc.), the relative changes in the forward voltage can be monitored with high precision, which can specifically help to compensate for any changes in the LED output power and, therefore, can be used to compensate for any light signal changes of the detector.

[0118] In another example, the spectrometer device can additionally include at least one shunt resistor to determine both the LED voltage drop and the LED current, while the input current to the ROIC can be ignored. Thus, in addition to the forward voltage, the input electrical power into the LED can also be monitored, which can improve the accuracy with which optical signal compensation can be performed. This type of operation may require matched readout IC channels so that inherent offsets do not generate current offsets. Each side of the shunt resistor can be electrically connected to a multi-channel readout integrated circuit via at least one of the resistors. This configuration can enable high-resolution, short-term, time-based power drift compensation methods, specifically enabling improved detector readings. The overall power measurement may not be very accurate, but the high resolution can be used for relative compensation methods. Additionally, if the thermal characteristics of the light source (such as heat capacity and / or conductivity to the PCB and / or conversion efficiency) are known, the light source temperature can be estimated from the power dissipated in the light source.

[0119] Both measurement examples (specifically determining the forward voltage and / or power measurement of the light source) can be performed at different stages of the spectrometer device's lifetime (e.g., end-of-line testing, open port measurements, the measurement itself, calibration measurements, etc.). Additionally, when multiple light sources are used (in which case potential drift effects may be common to all light sources or specific to a single light source), information can be determined as to whether the drift occurs in the ROIC or in the light source itself.

[0120] Additionally or alternatively, other types of light sources can also be monitored with the aid of the ROIC, even if these have different electrical and optical properties. As an example, the light source can include an incandescent light source. The filament of an incandescent lamp can be a metallic resistor. Consequently, the heating of the light source follows Joule's law, and the emitted radiation follows Planck's law. By determining the current flowing through the filament and the voltage applied thereto, the resistance of the filament can be determined, wherein this resistance can be temperature-dependent. By keeping the resistance of the filament constant with the aid of a current and voltage control loop, the radiation spectrum from the light source can also be stabilized. This skimming current compensation can be used for forward voltage measurement as well as for power dissipation measurement.

[0121] Alternatively or additionally, a negative thermal coefficient thermistor (NTC) can be used for direct temperature measurement. By positioning the NTC near or in direct contact with the light source and determining the resistance of the NTC, the temperature and therefore the optical output of the light source can be monitored.

[0122] The spectrometer apparatus and method according to the present invention can specifically allow for rapid sampling. Thus, the high-frequency noise of the light source input, measured via voltage and power, can be correlated with the light source output, measured via the detector signal. This can increase the signal-to-noise ratio of the measured detector signal.

[0123] As used herein, the terms "having," "including," or "comprising," or any grammatical variations thereof, are used in a non-exclusive manner. Thus, these terms can refer to the absence of additional features in the entity described in that context, in addition to the features introduced by these terms, or the presence of one or more additional features. By way of example, the expressions "A has B," "A includes B," and "A contains B" can refer to the absence of any other elements in A besides B (i.e., A consists solely and solely of B), or the presence of one or more additional elements in entity A, such as element C, elements C and D, or even additional elements, in addition to B.

[0124] Furthermore, it should be noted that the terms "at least one", "one or more", or similar expressions indicating that a feature or element may occur once or more than once are typically used only once when introducing the corresponding feature or element. In most cases, the expression "at least one" or "one or more" is not repeated when referring to the corresponding feature or element, although the corresponding feature or element may occur once or more than once.

[0125] Further, as used herein, the terms "preferably", "more preferably", "particularly", "more particularly", "specifically", "more specifically" or similar terms are used in conjunction with optional features, without limiting the possibilities of alternatives. Therefore, the features introduced by these terms are optional features and are not intended to limit the scope of the claims in any way. As the skilled person will recognize, the present invention can be carried out through the use of alternative features. Similarly, features introduced by "in an embodiment of the invention" or similar expressions are intended to be optional features, without any limitation on alternative embodiments of the invention, without any limitation on the scope of the invention, and without any limitation on the possibility of combining features introduced in this manner with other optional or non-optional features of the invention.

[0126] In summary, and without excluding further possible embodiments, the following embodiments may be envisaged:

[0127] Embodiment 1: A spectrometer device for obtaining spectroscopic information about at least one object, the spectrometer device comprising:

[0128] i at least one light source, the at least one light source for generating illumination light for illuminating the object;

[0129] ii. at least one detector for detecting light from the object and for generating at least one detector signal;

[0130] iii. at least one driving unit, the at least one driving unit for electrically driving the light source;

[0131] iv. at least one multi-channel readout integrated circuit, wherein each channel of the multi-channel readout integrated circuit comprises at least one buffered direct injection (BDI) circuit, wherein the BDI circuit is configured to read out the detector signal, wherein the BDI circuit is configured to generate at least one information item about an electrically measurable quantity required to drive the light source (114), wherein the multi-channel readout integrated circuit comprises at least one multi-channel readout application specific integrated circuit (ASIC), the at least one multi-channel readout application specific integrated circuit being configured to synchronously sample the detector signal and the information item about the electrically measurable quantity required to drive the light source (114); and

[0132] v. at least one evaluation unit for evaluating at least one detector signal generated by the detector and for deriving the spectroscopic information about the object from the detector signal, wherein the evaluation unit is configured to take into account the information item about the electrically measurable quantity required to drive the light source when deriving the spectroscopic information from the detector signal.

[0133] Embodiment 2: The spectrometer device according to the previous embodiment, wherein the light source is configured to emit light in a spectral range that at least partially includes the infrared spectral range, specifically the near-infrared spectral range, more specifically in the spectral range from 760 nm to 3 µm, more specifically in the spectral range from 1 to 3 µm, preferably from 1.3 µm to 2.5 µm, more preferably from 1.5 µm to 2.2 µm.

[0134] Embodiment 3: A spectrometer device according to any one of the preceding embodiments, wherein the light source comprises at least one light source selected from the group consisting of: an incandescent lamp; a light emitting diode (LED); a laser, in particular a laser diode, a solid-state laser, a gas laser, a quantum cascade laser; a plasma light source; a low-pressure discharge lamp, in particular a low-pressure fluorescent lamp; a high-pressure discharge lamp; an electric light source.

[0135] Embodiment 4: The spectrometer device according to any of the preceding embodiments, wherein the light source comprises at least one light emitting diode and at least one luminescent material for photoconverting the primary light generated by the light emitting diode.

[0136] Embodiment 5: A spectrometer device according to any of the preceding embodiments, wherein the information item about the electrically measurable quantity required to drive the light source includes at least one information item selected from the group consisting of: a forward voltage at the light source; a voltage drop at the light source; a current at the light source; an electrical power input to the light source; a resistance of the light source; an impedance of the light source.

[0137] Embodiment 6: The spectrometer device according to any one of the preceding embodiments, wherein the multi-channel readout application specific integrated circuit (ASIC) comprises at least one skimming circuit configured to current skim the current at the detector.

[0138] Embodiment 7: A spectrometer device according to the previous embodiment, wherein the skimming circuit comprises at least one programmable current sink, and the at least one programmable current sink comprises one or more transistors, specifically a plurality of transistors, wherein the transistors have the same size and are constructed in parallel, or have twice the size and are constructed in series.

[0139] Embodiment 8: The spectrometer device according to any one of the preceding embodiments, further comprising at least one resistor electrically connecting the light source and the multi-channel readout integrated circuit.

[0140] Embodiment 9: The spectrometer device according to any one of the preceding embodiments further comprises at least two resistors and at least one shunt resistor, the at least two resistors electrically connecting the light source to the multi-channel readout integrated circuit, wherein each side of the shunt resistor is electrically connected to the multi-channel readout integrated circuit via at least one of the resistors.

[0141] Embodiment 10: The spectrometer device according to any of the two preceding embodiments, wherein the resistor and / or the shunt resistor has a temperature coefficient of less than 1000 ppm / K, specifically less than 100 ppm / K, more specifically less than 50 ppm / K, more specifically less than 10 ppm / K.

[0142] Embodiment 11: A spectrometer device according to any of the preceding embodiments, wherein the detector comprises a plurality of photosensitive elements, in particular an array of photosensitive elements, wherein each of these photosensitive elements is configured to generate at least one detector signal, wherein the evaluation unit is configured to consider the information item about the electrically measurable quantity required to drive the light source separately for each of the detector signals of these photosensitive elements, and to combine these detector signals to obtain the spectroscopic information.

[0143] Embodiment 12: The spectrometer device according to the preceding embodiment, wherein the spectrometer device is configured such that the light sensitive elements are sensitive to different spectral ranges of the light from the object.

[0144] Embodiment 13: The spectrometer device according to the preceding embodiment, wherein the spectrometer device comprises at least one wavelength selective element arranged in the beam path of the detection light, wherein the wavelength selective element is configured such that each photosensitive element is exposed to a separate spectral range of the detection light from the object.

[0145] Embodiment 14: According to the spectrometer device according to any one of the preceding embodiments, the spectrometer device further includes at least one wavelength selection element, which includes at least one of a wavelength selection element arranged in the beam path of the illumination light and a wavelength selection element arranged in the beam path of the detection light.

[0146] Embodiment 15: The spectrometer device according to the preceding embodiment, wherein the wavelength selective element is selected from the group consisting of a tunable wavelength selective element and a wavelength selective element with a fixed transmission spectrum.

[0147] Embodiment 16: The spectrometer according to the preceding embodiment, wherein the wavelength selective element with a fixed transmission spectrum comprises at least one filter element, in particular at least one absorption filter element, more particularly a bandpass filter element.

[0148] Embodiment 17: The spectrometer device according to any one of the two preceding embodiments, wherein the tunable wavelength selection element comprises at least one tunable interferometer, specifically at least one of a MEMS Fabry-Perot interferometer and a MEMS Michelson interferometer.

[0149] Embodiment 18: A method of obtaining spectroscopic information about at least one object by using a spectrometer device, the method comprising:

[0150] a. by using at least one driving unit to electrically drive at least one light source;

[0151] b. illuminating the object with illumination light generated by the light source;

[0152] c. generating at least one detector signal by detecting detection light from the object using at least one detector;

[0153] d. generating at least one item of information about an electrically measurable quantity required to drive the light source by using at least one multi-channel readout integrated circuit, wherein each channel of the multi-channel readout integrated circuit comprises at least one buffered direct injection (BDI) circuit, wherein the BDI circuit is configured to read out the detector signal, wherein the BDI circuit is configured to generate the at least one item of information about the electrically measurable quantity required to drive the light source, wherein the multi-channel readout integrated circuit comprises at least one multi-channel readout application specific integrated circuit (ASIC), the at least one multi-channel readout application specific integrated circuit being configured to synchronously sample the detector signal and the item of information about the electrically measurable quantity required to drive the light source; and

[0154] e. deriving the spectroscopic information about the object from the detector signal by evaluating the at least one detector signal generated by the detector using at least one evaluation unit and taking into account the item of information about the electrically measurable quantity required to drive the light source.

[0155] Embodiment 19: The method according to the preceding embodiment, wherein a spectrometer device according to any of the preceding embodiments involving a spectrometer device is used.

[0156] Embodiment 20: A method according to any one of the aforementioned embodiments relating to methods, wherein steps c. and d. are performed in a time-overlapping manner, specifically in parallel.

[0157] Embodiment 21: A method according to any one of the preceding embodiments involving methods, wherein the method is performed on-site online.

[0158] Embodiment 22: A method according to any of the preceding embodiments relating to methods, wherein, in step e., at least one correction is determined based on the information item about the electrically measurable quantity required to drive the light source, wherein, further, the at least one detector signal is corrected by using the correction.

[0159] Embodiment 23: The method according to the preceding embodiment, wherein the correction comprises at least one temperature correction, the temperature correction being at least partially dependent on the item of information about the electrically measurable quantity required to drive the light source.

[0160] Embodiment 24: The method according to any of the two preceding embodiments, wherein the correction comprises multiplying the at least one detector signal by at least one correction factor.

[0161] Embodiment 25: The method according to any one of the three preceding embodiments, wherein a corrected detector signal is used to obtain the spectroscopic information.

[0162] Embodiment 26: The method according to any of the preceding embodiments relating to methods, wherein at least step e. of the method is computer-implemented.

[0163] Embodiment 27: A computer program comprising instructions, which, when executed by a spectrometer device according to any one of the preceding embodiments relating to a spectrometer device, cause the spectrometer device to perform a method according to any one of the preceding embodiments relating to a method.

[0164] Embodiment 28: A computer-readable storage medium, specifically a non-transitory computer-readable medium, comprising instructions, which, when executed by a spectrometer device according to any one of the aforementioned embodiments involving spectrometer devices, cause the spectrometer device to perform a method according to any one of the aforementioned embodiments involving methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0165] Additional optional features and embodiments will be disclosed in more detail in the subsequent embodiments, preferably in conjunction with the dependent claims. As will be appreciated by those skilled in the art, the respective optional features can be implemented independently and in any feasible combination. The scope of the present invention is not limited by the preferred embodiments. The embodiments are schematically depicted in the accompanying drawings. Identical reference numerals in these drawings represent identical or functionally equivalent elements.

[0166] In the attached figure:

[0167] Figure 1 A schematic overview of a spectrometer apparatus is shown;

[0168] Figure 2 shows a schematic cross-sectional view of a light source;

[0169] Figure 3 shows a schematic flow chart illustrating the generation and processing of detector signals;

[0170] Figure 4 shows a graph representing an overlay of infrared radiation spectra of a phosphor LED at various temperatures;

[0171] Figure 5 shows a graph representing the variation of transmitted power as a function of temperature for a selected number of wavelengths;

[0172] Figure 6 shows a graph of the forward voltage versus temperature for a selected current;

[0173] Figure 7A and Figure 7B The spectra of two different types of phosphor LEDs are shown;

[0174] Figure 8A and Figure 8B The attenuation constant ( Figure 8A ) and the growth constant ( Figure 8B )

[0175] Figure 9A and Figure 9B The attenuation constant ( Figure 9A ) and the growth constant ( Figure 9B )

[0176] Figure 10 shows a graph representing normalized light output as a function of forward current;

[0177] Figure 11 A flow chart illustrating an embodiment of a method of obtaining spectroscopic information about at least one object by using a spectrometer device;

[0178] 12A to 12D Various embodiments of exemplary channels of the ROIC are shown; and

[0179] Figure 13 A graph showing the current-voltage characteristics of a light emitting diode (LED) is shown. DETAILED DESCRIPTION

[0180] exist Figure 1 , a schematic overview of a spectrometer device 110 for obtaining spectroscopic information about at least one object 112 is shown. The spectrometer device 110 may comprise Figure 1The following will refer to the multiple components shown. Figure 1 Possible components of a spectrometer device 110 and their interactions are described. Spectrometer device 110 includes at least one light source 114 for generating illumination light 116 for illuminating an object 112. Light source 114 can be at least one of a tunable light source, a light source having at least one fixed emission wavelength, and a broadband light source. Light source 114 can specifically be or include at least one electric light source. Light source 114 includes at least one light-emitting diode 118 and at least one luminescent material 120 for photoconverting primary light generated by light-emitting diode 118. By way of example, light-emitting diode 118 can include one or more of the following: a light-emitting diode (LED) based on spontaneous optical emission, a light-emitting diode (sLED) based on superluminescent emission, or a laser diode (LLED).

[0181] LED 118 may specifically include at least two semiconductor material layers 121, wherein light may be generated at at least one interface between the at least two semiconductor material layers 121, specifically due to the recombination of positive and negative charges. The at least two semiconductor material layers 121 may have different electrical properties, such as at least one of the layers being an n-doped semiconductor material 121 and at least one of the layers being a p-doped semiconductor material 121. Thus, as an example, LED 118 may include at least one pn junction and / or at least one pin structure. However, it should be noted that other device structures are also possible.

[0182] The light-emitting diodes 118 can generate primary light, which can also be referred to as "pump light." The primary light can then be converted into "secondary light," for example, using light conversion (e.g., by one or more luminescent materials 120, such as phosphor materials). Thus, at least one luminescent material 120 can form at least one converter (also referred to as a light converter) that converts the primary light into secondary light having different spectral characteristics than the primary light. Specifically, the spectral width of the secondary light can be greater than the spectral width of the primary light, and / or the emission center of the secondary light can be offset (specifically, red-shifted) compared to the primary light. Specifically, the at least one luminescent material 120 can have an absorptive property in the ultraviolet and / or blue spectral ranges, and an emissive property in the near-infrared and / or infrared spectral ranges. The illumination light 116 can be or include at least one of the primary light or a portion thereof, the secondary light or a portion thereof, or a mixture of the primary light and the secondary light.

[0183] like Figure 1As indicated, the light source 114 may specifically include a phosphor light emitting diode 122, also referred to as a phosphor LED 122. The phosphor LED 122 may be a combination of at least one light emitting diode 118 configured to generate primary light or pump light and at least one luminescent material 120 (also referred to as a "phosphor") configured to photoconvert the primary light generated by the light emitting diode 118. The phosphor LED 122 may form a packaged LED light source including an LED die 124 (e.g., a blue LED emitting blue pump light) and a phosphor that, for example, fully or partially coats the LED 118 and, as an example, is configured to convert the primary light or blue light into light having different spectral characteristics (specifically, into near-infrared light). Figure 2 A more detailed view of the light source 114 implemented as a phosphor LED 122 is shown.

[0184] Generally, the light source 114 can be implemented in various ways. Thus, the light source 114 can be, for example, a part of the spectrometer device 110 in the housing 126 of the spectrometer device 110, such as Figure 1 However, alternatively or additionally, the at least one light source 114 can also be arranged outside the housing 126, for example as a separate light source 114 (not shown). The light source 114 can be arranged separately from the object 112 and illuminate the object 112 from a distance, such as Figure 1 As indicated.

[0185] Illumination light 116, as generated by light source 114, may propagate from light source 114 to object 112. Figure 1 , illumination light 116 generated by a light source 114 and propagating to an object 112 is illustrated by an arrow. Specifically, the object 112 may include at least one sample that may be analyzed completely or partially by spectroscopic methods.

[0186] As from Figure 1 As apparent in FIG, the spectrometer device 110 further includes at least one detector 128 configured to detect detection light 130 from the object 112. 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 detector 128 may be referred to as “detection light” 130. Figure 1, detection light 130 is indicated by an arrow. Detection light 130 may include at least one of the following: illumination light 116 reflected by object 112, illumination light 116 scattered by object 112, illumination light 116 transmitted by object 112, or luminescent light generated by object 112 (e.g., phosphorescence or fluorescence generated by object 112 after object 112 is optically, electrically, or acoustically excited by illumination light 116). Therefore, detection light 130 may be generated directly or indirectly by illumination light 116 irradiating object 112.

[0187] Detector 128 may be or include at least one optical detector 132. Optical detector 132 may be configured to determine at least one optical parameter, such as the intensity and / or power of light irradiating at least one sensitive area of ​​detector 128. More specifically, optical detector 132 may include at least one photosensor and / or at least one optical sensor, such as at least one of a photodiode, a photocell, a photoresistor, a phototransistor, a thermopile sensor, a photoacoustic sensor, a pyroelectric sensor, a photomultiplier, and a bolometer. Thus, detector 128 may be configured to generate at least one detector signal, more specifically at least one electrical detector signal in the aforementioned sense, that provides information about at least one optical parameter, such as the power and / or intensity of light irradiating detector 128 or a sensitive area of ​​detector 128.

[0188] Detector 128 may include a single optically sensitive element or region or a plurality of optically sensitive elements or regions. Figure 1 As indicated, detector 128 may include at least one detector array, more specifically an array of photosensitive elements 134. Each photosensitive element 134 may be configured to generate at least one detector signal. In particular, each photosensitive element 134 may include at least a photosensitive region that may be adapted to generate an electrical signal depending on the intensity of incident light, wherein the electrical signal may in particular be provided to an evaluation unit 136 of spectrometer device 110, as will be further detailed below.

[0189] In the case where detector 128 comprises an array of optically sensitive elements 134, detector 128 can, for example, be selected from any known pixel sensor, in particular from a CCD chip or a CMOS chip. Alternatively, detector 128 can generally be or include a photoconductor, in particular an inorganic photoconductor, especially PbS, PbSe, Ge, InGaAs, extended InGaAs, InSb, or HgCdTe. As another alternative, the detector can include at least one of a pyroelectric element, a bolometer element, or a thermopile detector element.

[0190] The spectrometer device 110 comprises at least one evaluation unit 136 for evaluating at least one detector signal generated by the detector 128 and for deriving spectroscopic information about the object 112 from the detector signal. The detector 128 can directly or indirectly provide the detector signal to the evaluation unit 136. Thus, the detector 128 and the evaluation unit 136 can be directly or indirectly connected, e.g. Figure 1 The detector signal can be used as a "raw" detector signal and / or can be processed or pre-processed (e.g., by filtering, etc.) before further use. Thus, the detector 128 can include at least one processing device and / or at least one pre-processing device, such as at least one of an amplifier, an analog / digital converter, an electrical filter, and a Fourier transform.

[0191] like Figure 1 As shown, the spectrometer device 110 further includes at least one driving unit 138 for electrically driving the light source 114. In particular, the driving unit 138 may be configured to provide current to the LED 118, specifically for controlling the current through the LED 118. Therein, as an example, the driving unit 138 may be configured to adapt the voltage provided to the LED 118, which voltage is required to achieve a specific current through the LED 118. The driving unit 138 may specifically include one or more of the following: a current source 140, a voltage source. In particular, the driving unit 138 may include at least one current source 140 for providing at least one predetermined current to the LED 118, wherein the current source 140 may specifically be configured to adjust or control the voltage applied to the LED 118 so as to generate a predetermined current. As an example, the driving unit 138 may include one or more electrical components (such as integrated circuits) for driving the light source 114. The driving unit 138 may be fully or partially integrated into the light source 114, or may be separated from the light source 114, the latter configuration being preferred. Figure 1 In display.

[0192] Spectrometer device 110 further includes at least one multi-channel readout integrated circuit 139. Each channel of multi-channel readout integrated circuit 139 includes at least one buffered direct injection (BDI) circuit 141. BDI circuit 141 is configured to read out the detector signal. BDI circuit 141 is configured to generate at least one information item regarding an electrically measurable quantity required to drive light source 114. Multi-channel readout integrated circuit 139 includes at least one multi-channel readout application-specific integrated circuit (ASIC) 142, which is configured to synchronously sample the detector signal and the information item regarding the electrically measurable quantity required to drive light source 114. 12A to 12DA possible embodiment of a multi-channel readout integrated circuit 139 is shown in FIG. Therefore, for a detailed description of the ROIC, reference is made to FIG. 12A to 12D Description.

[0193] As outlined above, the BDI circuit 141 can be configured to generate at least one electrically measurable quantity (particularly a forward voltage) required to drive the light source 114, and in particular, the light emitting diode 118. The forward voltage can be applied to the LED 118 in the forward direction, i.e., by applying the positive contact of the voltage or current source 140 to the p-layer of the LED 118 and the negative contact to the n-layer of the LED 118, so as to generate a predetermined current through the LED 118. As an example, the predetermined current defining the forward voltage can be a current known to generate a predetermined light output of the light source 114 and / or the light emitting diode 118.

[0194] As outlined above, and as Figure 1 As shown, spectrometer device 110 includes at least one evaluation unit 136 for evaluating at least one detector signal generated by detector 128 and for deriving spectroscopic information about object 112 from the detector signal. Evaluation unit 136 is configured to take into account information about at least one electrically measurable quantity, in particular, the forward voltage, when deriving the spectroscopic information from the detector signal. Specifically, evaluation unit 136 can be configured to process at least one input signal and generate at least one output signal thereof. As an example, the at least one input signal can include at least one detector signal provided directly or indirectly by at least one detector 128 and at least one signal provided directly or indirectly by ROIC 139, which includes at least one information item about at least one electrically measurable quantity, in particular, the forward voltage. Figure 1 The drive unit 138 (which at least partially includes Figure 1 The arrows between the ROIC 139 and the evaluation unit 136 in the illustrated embodiment illustrate the provision of a signal to and / or retrieval by the evaluation unit 136 , the signal comprising at least one item of information about at least one electrically measurable quantity, in particular the forward voltage.

[0195] The evaluation unit 136 may be or may include one or more integrated circuits (e.g., 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 processors (DSPs), field-programmable gate arrays (FPGAs)), preferably one or more microcomputers and / or microcontrollers. Additional components may be included, such as one or more pre-processing devices 146 and / or data acquisition devices, such as one or more devices for receiving and / or pre-processing detector signals, such as one or more A / D converters and / or one or more filters. Furthermore, the evaluation unit may include one or more data storage devices 148, such as Figure 1 Furthermore, the evaluation unit 136 may include one or more interfaces, such as one or more wireless interfaces and / or one or more wired interfaces.

[0196] Specifically, evaluation unit 136 can be configured, for example through software programming, to determine at least one correction based on information about at least one electrically measurable quantity (particularly the forward voltage), specifically a correction based on a model describing the functional relationship between the spectral characteristics of light source 114 and the at least one electrically measurable quantity (particularly the forward voltage). Evaluation unit 136 can further be configured to correct at least one detector signal using the correction. As described in detail above and further exemplarily described below, the correction can specifically include multiplying the at least one detector signal by at least one correction factor. Evaluation unit 136 can specifically be configured to use the corrected detector signal to derive spectroscopic information.

[0197] As described in more detail above, the detector 128 can specifically include an array of photosensitive elements 134. Each photosensitive element can be configured to generate at least one detector signal. The evaluation unit 136 can be configured to individually correct each detector signal and to combine the detector signals to obtain spectroscopic information. The spectrometer device 110 can be configured such that the photosensitive elements of the detector 128 are sensitive to different spectral ranges of the light from the object 112. In particular, the detector 128 can be configured to generate detector signals for at least two different spectral ranges of the light from the object 112, specifically in a manner at least one of sequential and simultaneous. The spectrometer 110 can specifically include at least one filter element 150 arranged in the beam path of the light from the object 112. The filter element 150 can specifically be configured such that each photosensitive element is exposed to a separate spectral range of the light from the object 112.

[0198] The spectrometer device 110 may further include one or more optical components 151, such as one or more of at least one mirror, at least one lens, at least one aperture, and at least one wavelength selective element 152. Specifically, the one or more optical components 151 may be arranged in at least one of the beam path of the illumination light 116 and the beam path of the detection light 130. The spectrometer device 110 may particularly include at least one wavelength selective element 152. The wavelength selective element 152 may be selected from the group consisting of a tunable wavelength selective element 152 and a wavelength selective element 152 with a fixed transmission spectrum. By way of example, a tunable wavelength selective element 152 allows for sequential selection of different wavelength ranges, while a wavelength selective element 152 with a fixed transmission spectrum allows for a fixed wavelength range selection, or may also depend on, for example, the detector position. The wavelength selective element 152 may be used to separate incident light into a spectrum of component wavelength signals, the respective intensities of which are determined using a detector (such as the detector 128 of the spectrometer device 110, which may include an array of photosensors 134). The at least one wavelength selection element 152 may include, for example, at least one of a filter, a grating, and a prism. The wavelength selection element 152 may specifically include at least one of a wavelength selection element 152 disposed in the beam path of the illumination light 116 and a wavelength selection element 152 disposed in the beam path of the detection light 130. Figure 1 An embodiment of a spectrometer device 110 is shown having one wavelength selective element 152 arranged in the beam path of the illumination light 116 and one wavelength selective element 152 arranged in the beam path of the detection light 130 .

[0199] like Figure 1Spectrometer device 110, schematically shown in FIG. , is configured to obtain spectroscopic information about at least one object 112. Specifically, spectrometer device 110 may be configured to obtain, for example, an item of information about at least one object 112 and / or radiation emitted by at least one object 112, the information item characterizing at least one optical property of object 112, more specifically, at least one item of information characterizing, for example, qualitatively and / or quantitatively, at least one of transmission, absorption, reflection, and emission of at least one object 112. By way of example, the at least one spectral information item may include at least one item of intensity information, such as information about the intensity of at least one of light transmitted, absorbed, reflected, or emitted by object 112, the intensity being, for example, a function of wavelength or a wavelength subrange within one or more wavelengths (e.g., within a wavelength range). Thus, spectrometer device 110 may be configured to acquire at least one spectrum, or at least a portion of a spectrum, of detection light 130 propagating from object 112 to detector 128. The spectrum can describe the spectral flux in units of radiometric measurements, for example, given in Watts per nanometer (W / nm), or in other units, for example, as a function of the wavelength of the detection light 130. Thus, the spectrum can describe the optical power of light within a specific wavelength band, for example, in the NIR spectral range. The spectrum can include one or more optical variables that vary with wavelength, such as power spectral density, an electrical signal obtained by optical measurement, etc. Examples of spectra are, for example, Figure 4 、 Figure 7A and Figure 7B The spectrometer device 110 may specifically be a portable spectrometer device 110 , which may in particular be used on site.

[0200] exist Figure 2 A schematic cross-sectional view of a light source 114 is shown in FIG. The at least one light source 114 of the spectrometer device 110 can be configured to generate or provide electromagnetic radiation in one or more of the infrared, visible, and ultraviolet spectral ranges. Because many material properties or chemical composition characteristics of many objects 112 can be derived from the near-infrared spectral range, light typically used for the purposes of the present invention is light in the infrared (IR) spectral range, more preferably in the near-infrared (NIR) and / or mid-infrared (MidIR) spectral ranges, particularly light with a wavelength of 1 to 5 µm, preferably 1 to 3 µm. The light source 114 includes at least one light-emitting diode 118 and at least one luminescent material 120 for photoconverting the primary light generated by the light-emitting diode 118. As described above, the LED 118 and the luminescent material 120 together can form a phosphor LED 122.

[0201] like Figure 2As shown, the phosphor LED 122 may include one or more functional components. Specifically, the phosphor LED 122 may include one or more substrates 154, specifically one or more electrically insulating substrates 154. In particular, the phosphor LED 122 may include one or more ceramic substrates 156, such as Figure 2 As shown. The substrate 154 can be configured to hold at least one LED die 124 and at least one luminescent material 120. Further, at least one substrate 154 can hold or include one or more electrical connection components, such as Figure 2 One or more contact pads 158 and / or one or more electrical leads, such as one or more metal contacts and / or one or more metal leads, are shown. The substrate 154 can be configured to act as a heat sink. For example, during the conversion process, heat can be generated in the LED die 124 (e.g., due to the finite conversion of electrical energy to photon energy) and in the luminescent material 120. The heat can be dissipated in the substrate 154, such as a ceramic substrate.

[0202] like Figure 2 As shown, the phosphor LED 122 may include a light emitting diode 118. The light emitting diode 118 may be configured to use Figure 2 The at least one LED chip and / or at least one LED die 124 shown converts electric current into primary light, such as blue primary light. In particular, a pn junction diode can be used. As an example, one or more LEDs 118 selected from the group consisting of an indium gallium nitride (InGaN)-based LED 118, a GaN-based LED 118, an InGaN / GaN alloy-based LED 118, or a combination thereof, and / or other LEDs 118 can be used. Additionally or alternatively, quantum well LEDs 118 can also be used, such as one or more quantum well LEDs 118 based on InGaN. Additionally or alternatively, superluminescent LEDs (sLEDs) and / or quantum cascade lasers can be used. As shown in FIG. Figure 2 As will be further apparent from the foregoing, the phosphor LED 122 may include at least one luminescent material 120 configured to light-convert the primary light generated by the light-emitting diode 118. Various types of conversion and / or luminescence are known and may 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-doped Sialon; copper and aluminum co-doped zinc sulfide (ZnS:Cu,Al).

[0203] The luminescent material 120 may in particular form at least one layer. In general, various alternatives for positioning the luminescent material 120 relative to the light-emitting diode 118 are feasible, which may be used individually or in combination. Firstly, the luminescent material 120 (e.g. at least one layer of the luminescent material 120, such as a phosphor) may be positioned directly on the light-emitting diode 118, e.g. with no material between the LED 118 and the luminescent material 120, or with one or more transparent materials in between, such as one or more transparent materials (in particular transparent to the primary light) between the LED 118 and the luminescent material 120. Thus, as an example, a coating of the luminescent material 120 may be placed directly or indirectly on the LED 118 (not shown). Additionally or alternatively, as an example, the luminescent material 120 may form at least one converter 160, such as at least one converter disc, which may also be referred to as a converter sheet. The converter 160 may be placed on top of the LED 118, e.g. as Figure 2 As shown, the converter 160 is attached to the LED 118 with an adhesive. Additionally or alternatively, the luminescent material 120 can be remotely positioned such that the primary light from the LED 118 must traverse an intermediate light path before reaching the luminescent material 120 (not shown). Again, by way of example, the remotely positioned luminescent material 120 can form a solid or converter 160, such as a disk or converter disk. One or more optical elements, such as one or more lenses, prisms, gratings, mirrors, apertures, or combinations thereof, can be positioned in the intermediate light path. Thus, in particular, an optical system with imaging properties can be positioned in the intermediate light path, between the LED 118 and the luminescent material 120. Thus, by way of example, the primary light can be focused or concentrated onto the converter 160.

[0204] In the light source 114 (specifically, the phosphor LED 122), at least one luminescent material 120 can be positioned relative to the light emitting diode 118 such that heat can be transferred from the light emitting diode 118 to the luminescent material 120. More specifically, the luminescent material 120 can be positioned such that heat can be transferred by one or both of thermal radiation and thermal conduction (more preferably by thermal conduction). Thus, as an example, the luminescent material 120 can be in thermal contact and / or physical contact with the light emitting diode 118, such as Figure 2 Thus, generally, the temperature of the light emitting material 120 and the temperature of the light emitting diode 118 can be coupled.

[0205] like Figure 2As shown, the light source 114 (specifically, the phosphor LED 122) can include additional components, such as at least one side coating 162 that covers at least one side (e.g., a top side, a bottom side, and / or one or more lateral sides) of at least one of the following: the substrate 154, the contact pads 158, the light emitting diode 118, and the luminescent material 120. In particular, the side coating 162 can cover voids and / or gaps that may be present in the layered arrangement of the light source 114, such as Figure 2 As shown. Other components of the light source 114 (specifically Figure 2 Typically, the light source 114 (particularly the phosphor LED 122) can be enclosed in a housing 126 ( Figure 2 Thus, the LED 118 and the at least one luminescent material 120 for light conversion of the primary light generated by the light emitting diode 118 can be accommodated in a common housing 126. Alternatively, however, the LED 118 can also be a housingless or bare LED 118, such as Figure 2 What is shown.

[0206] Figure 3 The schematic flow chart of FIG. 1 shows the process of generating a detector signal and processing the detector signal to generate a corrected signal, for example. Figure 3 , hardware components 164 that may participate in this process or in the generation and / or preprocessing of the detector signal, as well as software components 166 that may participate in the processing and / or correction of the detector signal, are shown. Hardware components 164 (also referred to simply as "hardware" 164) may specifically include at least one light-emitting diode 118 (particularly a blue LED 118) of the spectrometer device 110 configured to emit blue primary light. Hardware components 164 may further include a luminescent material 120 (also referred to as a phosphor LED 122), an object 112, and one or more optical components 151 (e.g., at least one wavelength-selective element 152), and a detector 128.

[0207] As part of the corrections that can be performed by the evaluation unit 136, corrections can be performed for temperature changes (even for local temperature changes within the light source 114), which may have an influence on the emission characteristics of the light source 114. Figure 3, the temperature of the selected hardware component 164 is indicated in FIG. For example, depending on the arrangement of the hardware component 164 (such as the relative position and distance of the hardware component in the spectrometer device 110), the hardware component 164 may have different or the same temperature. Specifically, as described above, the temperature of the luminescent material 120 and the temperature of the luminescent diode 118 may be coupled, for example, due to heat transfer caused by one or both of thermal radiation and thermal conduction between the LED 118 and the luminescent material 120. Therefore, in particular, the temperature of the LED 118 (also referred to as "T pn ”) and the temperature of the luminescent material 120 (also referred to as “T Ph ”) can be similar or even identical. Figure 3 In FIG. 1 , the temperature of the LED 118 is indicated by reference numeral 168, the temperature of the luminescent material 120 is indicated by reference numeral 170, and the temperature of the detector 128 (also referred to as “T D ”) is indicated by reference numeral 172.

[0208] When current flows through the LED 118 (eg, due to the driver unit 138 applying an appropriate voltage to the LED 118), the LED 118 may emit primary light so as to generate a specific current (eg, a predetermined current). Figure 3 The target signal S indicated by reference numeral 174 in FIG. t , to drive LED 118 to emit blue primary light. In particular, the target signal S t Reference numeral 174 may be a predetermined current value to be generated through the LED 118, for example, by applying an appropriate voltage. In particular, the predetermined current value may be in the range of 10 mA to 500 mA, more particularly in the range of 100 mA to 300 mA, for example, a current value of 50 mA. Thus, it is known that the predetermined current may generate a predetermined light output of the LED 118, such as a blue primary light. The LED 118 may be at a temperature "T" indicated by reference numeral 168. pn The blue primary light may be converted by the luminescent material 120 into secondary light, for example into light in the infrared spectral range. The luminescent material 120 may be at a temperature “T” indicated by reference numeral 170. ph”. The object 112 may be illuminated by illumination light 116 generated by the light source 114, which illumination light may include at least one of primary light or a portion thereof, secondary light or a portion thereof, or a mixture of primary light and secondary light. In order to guide the illumination light 116, one or more optical components 151 (such as one or more mirrors, lenses, wavelength selection elements 152 or other optical components 151) may be used, for example by placing the optical component 151 in the beam path of the illumination light 116. Detection light 130 (such as reflected light) from the object 112 may be guided to the detector 128. In the beam path of the detection light 130, one or more optical components 151 may also optionally be used. As an example, one or more wavelength selection elements 152, such as one or more dispersive elements, may be used, for example to separate the detection light 130 into its spectral components.

[0209] As described in more detail above, the detector 128 may, for example, include an array of photosensitive elements 134. Specifically, the detector 128 may be or may include a pixel sensor, such as a CCD chip or a CMOS chip, which includes a plurality of pixels arranged on the chip. As an example, each pixel may correspond to a predetermined spectral range, for example, by being sensitive to the predetermined spectral range. Thus, the detector 128 may generate a detector signal S px,i 176, such as Figure 3 As indicated by reference numeral 176 in the diagram, the detector signal comprises a plurality of detector signals. Thus, each of the plurality of detector signals may correspond to an electronic signal generated by one of the plurality of pixels of the detector 128. Each of the plurality of detector signals may be given, for example, as a numerical value corresponding to the number of counts of the corresponding pixel measured, for example, during a predetermined time span. Thus, the detector signal S px,i 176 may specifically be a function of the wavelength of the detection light 130, as indicated by the index "px". px,i 176 may further be a function of time (eg in the case of a time-dependent detector signal), as indicated by the index "i".

[0210] Detector signal S px,i The multiple signals included in 176 can be generated simultaneously or in a temporally continuous manner. px、i 176 can be used as Figure 3 The detector signal S is determined by the readout electronics 178 shown. px、i 176 can be processed, for example, as part of pre-processing and / or as part of a further processing step. As an example, the pixels comprised by the detector 128 can specifically be active pixel sensors that can be adapted to amplify the electronic detector signal S px,i176 , for example as part of a pre-processing process prior to further processing that may be performed, for example, by one or more of the software components 166 .

[0211] The signal S generated by the detector 128 px,i 176 may also be referred to as "frame signal S px,i 176". Figure 3 The provision of a signal S to one of the software components 166 is shown by an arrow. px,i 176 process. Specifically, it is configured to process and / or correct the detector signal S px,i The software component 166 of 176 may include at least one first software 180 (also referred to as “software 1”) and at least one second software 182 (also referred to as “software 2”). The first software 180 may be configured to detect the detector signal S px,i 176 performs at least one first processing step 184 (also referred to as “processing 1”), for example by applying at least one algorithm to the detector signal S px,i 176. In particular, the first processing step 184 may comprise at least one correction for transient effects or time-dependent effects. Thus, as an example, the first processing step 184 may comprise one or more of the following: a correction for a dark signal; a correction for a dark signal drift; a correction for fluctuation effects; a correction for the photodetector response of individual detector elements or individual time steps; a correction for environmentally induced (e.g. temperature-induced) variations in the photodetector response; extraction of information for subsequent processing; an addition or multiplication with a parameter, the addition or multiplication being generated based on information about at least one electrically measurable quantity (in particular the forward voltage) or about the device temperature. The first software 180 may be configured to perform at least one further step comprising performing at least one fast Fourier transformation 186 on the detector signal. Thus, as an example of applying the first processing step 184 and / or the fast Fourier transformation 186 to the detector signal S px,i 176, a signal S can be generated px 188 (also called "pixel signal S px 188”), the signal may no longer be a function of time. Specifically, the frame signal S px,i The time dependency of 176 can be eliminated by one or more of the steps forming part of the first software component 1, whereas the wavelength dependency may still be present in the start signal S px 188, as indicated by the index "pn". Figure 3 The provision of the signal S to the second software 182 is further illustrated by an arrow. px 188 process. The second software 182 can be configured to px188 performs at least one second processing step 190 (also referred to as “processing 2”), for example by applying at least one algorithm to the signal S px 188, thereby generating at least one corrected signal S px,corr 191. In particular, the second processing step 190 may comprise one or more of the following: correction of the dark signal; correction of dark signal drift; correction of fluctuation effects; correction of the photodetector response of individual detector elements or individual time steps; correction of environmentally induced (e.g. temperature induced) photodetector response variations; extraction of information for subsequent processing; manipulation of at least one parameter, e.g. addition or multiplication with a parameter, the addition or multiplication being generated as a function of information about at least one electrically measurable quantity (e.g. forward voltage) or about the device temperature. In particular, the corrected signal S px,corr 191 may include a plurality of corrected signals, such as a plurality of corrected electronic signals. Each of the plurality of corrected signals may specifically correspond to a corrected count number of a corresponding pixel.

[0212] Spectrometer device 110 includes at least one evaluation unit 136 for evaluating at least one detector signal generated by detector 128 and for deriving spectroscopic information about object 112 from the detector signal. Evaluation unit 136 is configured to take into account information about at least one electrically measurable quantity (in particular, the forward voltage) when deriving the spectroscopic information from the detector signal. Evaluation unit 136 can be configured, in particular by software programming, to evaluate and / or process the detector signal as part of a first processing step 184 of at least one first software 180. Evaluation unit 136 can specifically be configured to determine at least one correction based on the information about the at least one electrically measurable quantity (in particular, the forward voltage) and can further be configured to correct the at least one detector signal by using the correction. Thus, evaluation unit 136 can process and correct signal S px 188 to generate a signal S px,i,corr , the signal may then be further processed, for example by applying a Fast Fourier Transform 186 .

[0213] For example, as described in more detail above, both the light emitting diode 118 and the luminescent material 120 can be based on different materials and / or different material compositions, which generally affects the spectrum 192 of the phosphor LED 122. However, even when operated at a specific predetermined current, the spectrum 192 or spectral characteristics of a particular phosphor LED 122 may change with temperature. These changes can include a shift in the emission peak 193, a broadening or narrowing of the spectrum 192, an increase or decrease in emission, etc. However, in many cases, the emission at some wavelengths is affected to a greater extent than the emission at other wavelengths. This effect is caused by Figure 4 The graph shown shows a superposition of infrared radiation spectra 192 of phosphor LEDs 122 at various temperatures. Specifically, Figure 4 The graph in FIG shows the variation of power spectral density (PDS) 194 in microwatts per nanometer (µW / nm) on the y-axis 196 as a function of wavelength 198 given in nanometers on the x-axis 200. For the spectrum 192 shown, the temperature range at which the phosphor LED 122 generates the illumination light 116 is from 25°C to 50°C. Typically, there is a specific central wavelength within the spectrum 192 where the power spectral density generally does not vary with temperature. Therefore, each wavelength generally has its own temperature coefficient with respect to the increment / decrement of power. Thus, as shown from Figure 4 As is evident in Figure 19, the shape of the spectrum 192 changes with temperature. To visualize this effect more clearly, Figure 4 192. The wavelength intervals are delimited by dashed lines. Specifically, the following four wavelengths and their corresponding intervals are labeled with the following reference numerals: 1643 nm is indicated by reference numeral 202, 1750 nm is indicated by reference numeral 204, 1802 nm is indicated by reference numeral 206, and 1950 nm is indicated by reference numeral 208. For each of these wavelengths, Figure 5 The graph shows the variation of the transmit power normalized to the transmit power variation at 25°C over the temperature range from 25°C to 50°C. Figure 5 In the graph of , the transmit power variation (given in percentage) normalized to the transmit power variation at 25°C is shown on the y-axis 196 and denoted by reference numeral 219 , while the temperature in °C (denoted by reference numeral 220 ) is indicated on the x-axis 200 . Figure 5 The line in the graph in indicates the fitted curve 236. Figure 5As is apparent from the graph, the emission power at the central wavelength of 1802 nm can have very little variation (i.e., the emission power variation is zero or close to zero) over the observed temperature range, whereas for other wavelengths (e.g., for 1643 nm or 1953 nm), the emission power variation can have significant variation.

[0214] When a specific current (e.g., a current of a specific predefined value) is generated through the light emitting diode 118 by applying a forward voltage to the light emitting diode 118, the appropriate forward voltage may be a function of the temperature of the light emitting diode 118. Therefore, when the same current is applied to the light emitting diode 118, the forward voltage of the LED 118 generally decreases as the temperature increases. Each type of LED 118 has its own forward voltage-temperature characteristic curve. Generally, the forward voltage of the LED 118 decreases linearly as the temperature increases, such as when the temperature of the LED 118 is higher. to Slope in the range of V / K. Figure 6 This relationship is demonstrated for a particular LED 118. In particular, Figure 6 The graph shows the forward voltage applied to the LED 118 for generating a DC current of 150 mA through the LED 118 as a function of the temperature of the LED 118. The forward voltage in volts is indicated by reference numeral 224 on the y-axis 196. The temperature in °C is indicated by reference numeral 220 on the x-axis 200. Figure 6 As is evident from the figure, in this case the forward voltage decreases linearly with increasing temperature. Figure 6 The curve in can be described by the following equation:

[0215]

[0216] in, represents the forward voltage and T represents the temperature. Figure 6 In the diagram of FIG, a measurement point 221 represented by a gray solid circle and a dashed line corresponding to the above-given fitting curve 236 are shown. Instead of the relationship and / or curve between the forward voltage and the temperature as described above in an exemplary manner, a relationship between another electrically measurable quantity required to drive the light source and the temperature can be used, such as the fed electric power; current, resistance, inductance, capacitance, etc.

[0217] Thus, by using at least one electrically measurable quantity (in particular the forward voltage) as a correction parameter, the spectra 192 at different wavelengths can be individually temperature corrected. Specifically, the evaluation unit 136 can be configured to individually correct the detector signal S px,iThe method further comprises the steps of: generating a plurality of detector signals and combining the individually corrected detector signals to obtain spectroscopic information. As outlined above, the individual corrections can be performed by using an array of photosensitive elements 134, wherein each photosensitive element can be configured to generate at least one detector signal, and wherein each detector signal can be individually corrected using at least one electrically measurable quantity (particularly forward voltage) as a correction parameter. Finally, the corrected detector signals can be combined to obtain spectroscopic information.

[0218] In order to obtain spectroscopic information (in particular, a spectrum) about the object 112, the spectrometer device 110 (in particular, the evaluation unit 136) can specifically take into account the properties of the luminescent material 120 used in the light source 114. As outlined in more detail above, the luminescent material 120 can be configured to absorb primary photons generated by the light-emitting diode 118 and, in response, can emit secondary photons either instantaneously or after a delay or decay time. The signal or emission of the phosphor LED 122 after the forward current is turned off can be described using equations (1) and (2) as described above.

[0219] Thus, the characteristic of the luminescent material 120 may in particular be the decay constant 228 and the growth constant , the decay constant can describe the typical time of afterglow of the luminescent material 120, and the growth constant can describe the typical time to reach saturation of emission of the converted light. and The decay constant is typically different between different phosphor LEDs 122 and / or between different types of luminescent materials 120. and the growth constant Can depend on wavelength. These time constants are usually extracted from the step response of the optical signal by applying / cutting off the forward current. Figure 7A and Figure 7B Spectra 192 of two different types of phosphor LEDs 122 that emit light in the near infrared range are shown. Specifically, the power spectral density is shown as a function of wavelength, which is given in nm. Figure 7A and Figure 7B As is apparent from FIG, the spectra 192 of the two different phosphor LEDs 122 are different. Thus, as an example, Figure 7B The spectrum 192 shown in FIG. 1 reflects high emission in the range from 1850 nm to 1950 nm, whereas emission in this region is negligible for the phosphor LED 122, which has a spectrum 192 in the range from 1850 nm to 1950 nm. Figure 7A The phosphor LED 122 (whose spectrum is Figure 7A The decay constant is shown in and the growth constant respectively Figure 8A and Figure 8B The phosphor LED 122 (whose spectrum is given in Figure 7B The decay constant is shown in and the growth constant respectively Figure 9A and Figure 9B is given as a function of wavelength. Specifically, Figure 8A and Figure 9A The corresponding decay constant in ms is shown on the y-axis 196 (indicated by reference numeral 228 ) versus wavelength 198 in nm on the x-axis 200 ; and Figure 8B and Figure 9B The corresponding growth constant in ms is shown on the y-axis 196 (indicated by reference numeral 230) versus wavelength 198 in nm on the x-axis 200. Data points from different replicates are marked with different shades of grey.

[0220] Another characteristic of LEDs 118 is that their light output power varies with forward current. Thus, generally, by increasing the forward current (specifically, the input current), the power emitted by LED 118 increases. The shape (e.g., slope) of the light output versus forward current curve is characteristic of each LED 118. Figure 10 An example of such a curve is shown in FIG. Figure 10 In the graph of FIG. 1 , normalized light output 232 of the phosphor LED 122 is shown as a function of forward current 234, which is given in amperes.

[0221] Figure 11 1 shows a flow chart of an embodiment of a method for obtaining spectroscopic information about an object 112 by using a spectrometer device 110. Specifically, in this method, the method according to the present invention, such as the method according to the present invention, can be used. Figure 1 The exemplary embodiment described herein and / or the spectrometer device 110 according to any other embodiment disclosed herein. Therefore, for a detailed description of the spectrometer device 110 to be used in the method, reference is made to Figure 1 Description.

[0222] The method comprises the following steps, which may be performed in a given order. However, different orders are also possible. In particular, one, more than one, or even all of the method steps may be performed once or repeatedly. Furthermore, these method steps may be performed sequentially, or alternatively, one or more method steps may be performed in a timely overlapping manner or even in parallel and / or in a combined manner. The method may further comprise additional method steps not listed.

[0223] The method includes:

[0224] a. (Indicated by reference numeral 238 ) by using the driving unit 138 to electrically drive the light source 114 ;

[0225] b (denoted by reference numeral 240) illuminating the object 112 with the illumination light 116 generated by the light source 114;

[0226] c. (denoted by reference numeral 242 ) generating at least one detector signal by detecting the detection light 130 from the object 112 using the detector 128 ;

[0227] d. (indicated by reference numeral 244 ) generating at least one item of information about an electrically measurable quantity required for driving the light source 114 by using at least one multi-channel readout integrated circuit 139 , wherein each channel of the multi-channel readout integrated circuit 139 comprises at least one buffered direct injection (BDI) circuit 141 , wherein the BDI circuit 141 is configured to read out the detector signal, wherein the BDI circuit 141 is configured to generate at least one item of information about the electrically measurable quantity required for driving the light source 114 , wherein the multi-channel readout integrated circuit 139 comprises at least one multi-channel readout application specific integrated circuit (ASIC) 142 , wherein the at least one multi-channel readout application specific integrated circuit is configured to synchronously sample the detector signal and the item of information about the electrically measurable quantity required for driving the light source 114 ; and

[0228] e. (denoted by reference numeral 246 ) deriving spectroscopic information about the object 112 from the detector signal by evaluating at least one detector signal generated by the detector 128 using the evaluation unit 136 and taking into account items of information about electrically measurable quantities required to drive the light source 114 .

[0229] Specifically, if Figure 11 As indicated, steps c. and d. can be performed in a temporally overlapping manner, in particular in parallel.

[0230] Furthermore, in step e., at least one correction can be determined based on the information item about the electrically measurable quantity required to drive light source 114, wherein the at least one detector signal can further be corrected using the correction. The correction can specifically include at least one temperature correction. The temperature correction can depend at least in part on the information item about the electrically measurable quantity required to drive light source 114. The correction can include multiplying the at least one detector signal by at least one correction factor. The corrected detector signal can be used to obtain spectroscopic information.

[0231] 12A to 12D Various embodiments of exemplary channels of the ROIC 139 are shown. Specifically, Figure 12A and Figure 12B 1 shows an exemplary embodiment of channels of a multi-channel readout integrated circuit 139 configured for reading out detector signals, and Figure 12C and Figure 12D An exemplary embodiment of channels of a multi-channel readout integrated circuit 139 configured for generating items of information about electrically measurable quantities required to drive the light source 114 is shown.

[0232] As in Figure 12A As can be seen in FIG, an exemplary channel of the multi-channel readout integrated circuit 139 includes a buffered direct injection circuit 141. By applying a bias voltage to the BDI circuit 141 , the voltage applied to the detector 128 can be kept constant. The current generated by the applied voltage can be skimmed by means of current skimming to remove any offset in the signal. Figure 12A As shown, the ROIC 139, specifically the multi-channel readout ASIC 142, may include at least one skimming circuit 248 configured to skim the current at the detector 128. Any change in the detector resistance due to illumination may result in an increase in current flow, which may be digitized by an analog-to-digital converter (ADC) 250 having relatively high time and voltage resolution.

[0233] Additionally, if Figure 12B As shown, the skimming circuit 248 may include at least one programmable current sink 252 including a plurality of transistors (not shown). The transistors may be of the same size and connected in parallel, or may be twice the size and connected in series.

[0234] As outlined above, Figure 12C 1 shows exemplary channels of a multi-channel readout integrated circuit 139 configured to generate items of information about electrically measurable quantities required to drive a light source 114. In this example, the light source 114 may include an LED 118. Figure 12CAs shown, the spectrometer device 110 may further include at least one resistor 254 that electrically connects the light source 114 to the multi-channel readout integrated circuit 139. Specifically, in this case, the resistor 254 may electrically connect the anode of the LED 118 to the ROIC 139. Further, in this example, the resistor 254 may have resistance.

[0235] Additionally, as in Figure 12D As can be seen in FIG. 1 , the spectrometer device 110 may include at least one shunt resistor 256. In this example, Figure 12D As shown, the spectrometer device 110 may include at least two resistors 254. Each side of the shunt resistor 256 may be electrically connected to the multi-channel readout integrated circuit 139 via one of the resistors 254. Thus, both the voltage drop at the shunt resistor 256 and the current through the light source 114 may be determinable. As an example, the shunt resistor 256 may have The resistor 254 connecting the shunt resistor 256 to the ROIC 139 may have a resistance of The resistance. Figure 12C and Figure 12D In an example, resistor 254 and / or shunt resistor 256 can have a temperature coefficient of less than 1000 ppm / K, specifically less than 100 ppm / K, more specifically less than 50 ppm / K, and more specifically less than 10 ppm / K.

[0236] Figure 13 1 shows a graph having current-voltage characteristics of a light emitting diode (LED) 118. Specifically, the graph shows current 258 at the LED 118 as a function of voltage 260. As shown in FIG. Figure 13 As can be seen, if the current 258 at the LED 118 can be regulated to a constant current , specifically so that LED 118 maintains a constant level of power output, the voltage variation is minimal within the selected current range. For example, current 258 at LED 118 can be selected so that LED 118 can have a temperature-dependent forward voltage of 2.7 V to 2.9 V. In ROIC 139, the input voltage of BDI 141 can be set to a stable 2.6 V. Therefore, by connecting resistor 254, specifically a resistor with a low temperature coefficient as outlined above, between the anode of LED 118 and the input of ROIC 139, information items regarding electrically measurable quantities required to drive light source 114 in the region of interest of approximately 0.1 V to 0.3 V can be analyzed with high accuracy. However, other input voltages may also be feasible for other light sources 114. Thus, BDI 141 can function as an offset removal circuit.

[0237] List of Reference Numerals

[0238]

[0239]

[0240]

Claims

1. A spectrometer device (110) for obtaining spectroscopic information about at least one object (112), the spectrometer device (110) comprising: i. at least one light source (114) for generating illumination light (116) for illuminating the object (112), wherein the light source (114) comprises at least one electrically driven light source; ii. at least one detector (128) for detecting detection light (130) from the object (112) and generating at least one detector signal; iii. at least one driving unit (138), the at least one driving unit being configured to electrically drive the light source (114); iv. at least one multi-channel readout integrated circuit (139), wherein each channel of the multi-channel readout integrated circuit (139) comprises at least one buffered direct injection (BDI) circuit (141), wherein the BDI circuit (141) is configured for reading out the detector signal, wherein the BDI circuit (141) is configured for generating at least one item of information about an electrically measurable quantity required to drive the light source (114), wherein the multi-channel readout integrated circuit (139) comprises at least one multi-channel readout application specific integrated circuit (ASIC) (142), The at least one multi-channel readout ASIC is configured for synchronously sampling the detector signal and the information item about the electrically measurable quantity required to drive the light source (114), wherein the information item about the electrically measurable quantity required to drive the light source (114) comprises at least one information item selected from the group consisting of: a forward voltage at the light source (114); a voltage drop at the light source (114); a current at the light source (114); an electrical power input to the light source (114); a resistance of the light source (114); an impedance of the light source (114); and v. at least one evaluation unit (136) for evaluating at least one detector signal generated by the detector (128) and for deriving the spectroscopic information about the object (112) from the detector signal, wherein the evaluation unit (136) is configured to take into account the information item about the electrically measurable quantity required for driving the light source (114) when deriving the spectroscopic information from the detector signal, wherein the evaluation unit (136) is configured to determine at least one correction based on the information item about the at least one electrically measurable quantity, wherein the evaluation unit (136) is configured to correct the at least one detector signal by using the correction.

2. The spectrometer device (110) according to the preceding claim, wherein The light source (114) is configured to emit light in a spectral range that at least partially includes the infrared spectral range.

3. The spectrometer device (110) according to any one of the preceding claims, wherein The light source (114) comprises at least one light source selected from the group consisting of: an incandescent lamp; a light emitting diode (LED) (118); a light emitting diode (LED) (118) and at least one luminescent material (120) for photoconverting primary light generated by the light emitting diode (118); a laser, a solid-state laser, a gas laser, a quantum cascade laser; a plasma light source; a low-pressure discharge lamp; a high-pressure discharge lamp; an electric light source.

4. The spectrometer device (110) according to any one of the preceding claims, wherein The multi-channel readout application specific integrated circuit (ASIC) (142) includes at least one skimming circuit (248) configured to current skim the current at the detector (128).

5. The spectrometer device (110) according to any one of the preceding claims, further comprising at least one resistor (254) electrically connecting the light source (114) to the multi-channel readout integrated circuit (139).

6. The spectrometer device (110) according to any one of the preceding claims, further comprising at least two resistors (254) and at least one shunt resistor (256), the at least two resistors electrically connecting the light source (114) with the multi-channel readout integrated circuit (139), wherein Each side of the shunt resistor (256) is electrically connected to the multi-channel readout integrated circuit (139) via at least one of the resistors (254).

7. The spectrometer device (110) according to any one of the two preceding claims, wherein The resistor (254) and / or the shunt resistor (256) has a temperature coefficient of less than 1000 ppm / K.

8. The spectrometer device (110) according to any one of the preceding claims, wherein The detector (128) comprises a plurality of photosensitive elements, wherein each of the photosensitive elements is configured to generate at least one detector signal, wherein the evaluation unit (136) is configured to take into account the information item about the electrically measurable quantity required to drive the light source (114) individually for each of the detector signals of the photosensitive elements and to combine the detector signals to obtain the spectroscopic information.

9. The spectrometer device (110) according to the preceding claim, wherein The spectrometer device (110) is configured such that the photosensitive elements are sensitive to different spectral ranges of the light from the object (112), wherein the spectrometer device (110) comprises at least one wavelength selective element (152) arranged in the beam path of the detection light (130), wherein the wavelength selective element (152) is configured such that each of the photosensitive elements is exposed to a separate spectral range of the detection light (130) from the object (112).

10. A method of obtaining spectroscopic information about at least one object (112) by using a spectrometer device (110), the method comprising: a. electrically driving at least one light source (114) by using at least one driving unit (138), wherein the light source (114) comprises at least one electrically driven light source; b. illuminating the object (112) with illumination light (116) generated by the light source (114); c. generating at least one detector signal by detecting detection light (130) from the object (112) using at least one detector (128); d. generating at least one item of information about an electrically measurable quantity required to drive the light source (114) by using at least one multi-channel readout integrated circuit (139), wherein each channel of the multi-channel readout integrated circuit (139) comprises at least one buffered direct injection (BDI) circuit (141), wherein the BDI circuit (141) is configured to read out the detector signal, wherein the BDI circuit (141) is configured to generate at least one item of information about an electrically measurable quantity required to drive the light source (114), wherein the multi-channel readout integrated circuit (139) comprises at least one multi-channel readout-specific circuit integrated circuit (ASIC) (142), the at least one multi-channel readout application specific integrated circuit being configured for synchronously sampling the detector signal and the information item about the electrically measurable quantity required to drive the light source (114), wherein the information item about the electrically measurable quantity required to drive the light source (114) comprises at least one information item selected from the group consisting of: a forward voltage at the light source (114); a voltage drop at the light source (114); a current at the light source (114); an electrical power input to the light source (114); a resistance of the light source (114); an impedance of the light source (114); and e. deriving the spectroscopic information about the object (112) from the detector signal by evaluating the at least one detector signal generated by the detector (128) using at least one evaluation unit (136) and taking into account the item of information about the electrically measurable quantity required to drive the light source (114); wherein, in step e., at least one correction is determined from the item of information about the electrically measurable quantity required to drive the light source (114), wherein, further, the at least one detector signal is corrected by using the correction.

11. The method according to the preceding claim, wherein The correction comprises at least one temperature correction which depends at least in part on the item of information about the electrically measurable quantity required to drive the light source (114).

12. The method according to any one of the two preceding claims, wherein The spectroscopic information is obtained using the corrected detector signal.

13. A computer program comprising instructions which, when executed by a spectrometer device (110) according to any one of the preceding claims relating to a spectrometer device (110), cause the spectrometer device (110) to perform a method according to any one of the preceding claims relating to a method.

14. A computer-readable storage medium comprising instructions which, when executed by a spectrometer device (110) according to any one of the preceding claims relating to a spectrometer device (110), cause the spectrometer device (110) to perform a method according to any one of the preceding claims relating to a method.

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