Method for calibrating spectrometer device in batch of spectrometer devices

Abstract

A method for calibrating a spectrometer device in a batch of spectrometer devices is disclosed in the abstract of a method for calibrating a spectrometer device in a batch of spectrometer devices. The present invention relates to a spectrograph arrangement comprising at least one detector arrangement comprising at least one optical element configured to separate incident light into a spectrum having constituent wavelength components and further comprising a plurality of light sensitive elements, each photosensitive element is configured for receiving at least a portion of one of the constituent wavelength components and for generating a respective detector signal as a function of an illumination of the respective photosensitive element by at least a portion of the respective constituent wavelength component, the method comprising the following steps: a) at least one system characterization step, the at least one system characterization step comprises determining a line spread function at a corresponding wavelength by comparing at least one spectrum measured by using the spectrometer device with at least one reference spectrum; 15b) at least one resolution homogenization step comprising converting, for each wavelength, the resolution of the line spread function to a predefined target resolution for the corresponding wavelength, where the target resolution for each wavelength is a predefined target batch resolution value for the corresponding wavelength. 20 (Fig. 1A).

Description

Technical Field

[0001] The present invention relates to a method and a system for calibrating spectrometers in a batch of spectrometers. Further, the present invention relates to a computer program and a computer-readable storage medium for performing a method for calibrating spectrometers in a batch of spectrometers. The method and apparatus can be particularly used for calibrating spectrometers for research in the infrared spectral region, specifically the near-infrared spectral region and the mid-infrared spectral region. However, other spectrometers for optical research are also feasible. Background Art

[0002] Spectral methods are widely used in research, industrial, and customer applications to achieve various applications such as optical analysis and / or quality control. Use cases can be found in fields such as food, agriculture, pharmaceuticals, healthcare, and life sciences. There are various methods (such as photometric methods, absorptiometric methods, fluorometric methods, and Raman spectrometric methods) available to achieve qualitative and / or quantitative sample analysis. These methods generally involve mapping spectral information (such as the irradiance of a sample) at a specific wavelength to a specific physical part of a spectral device, for example, detector pixels, time intervals, etc.

[0003] For example, when transitioning from single-piece manufacturing to mass production, producing a large number of spectrometers usually has high requirements for spectral homogenization between different spectrometers. Specifically, in order to obtain an accurate prediction model when using any spectrometer in a given spectrometer group, quantitative and / or qualitative inferences from spectral data generally need to be reproducible between different spectrometers. For example, key parameters of different spectrometers (such as spectral resolution, stray light effects, and / or detector characteristics) either need to be the same or mitigation measures need to be taken.

[0004] Generally, there are different possible ways to achieve the same model prediction in a spectrometer group. As an example, homogenization at the production level ensures that all spectrometers are produced with very high precision, such that all key parameters characterizing the spectral performance of the spectrometers are almost the same in the spectrometer group. However, this may place extremely high requirements on production tolerances and / or production scrap rates.

[0005] As another example, homogenization can be achieved through model calibration by specifically calibrating a trainable model for each spectrometer in a spectrometer group. However, this method usually requires a large amount of work because each spectrometer must be calibrated for each potential use case it may be used for and / or each individual spectrometer may only be suitable for the specific use case for which it is calibrated.

[0006] Although known methods and apparatuses achieve these advantages, there are still several technical challenges. Specifically, if the spectral data for the same sample fed into a trainable model of spectral data is different from the noise limiting mechanism, the prediction accuracy of these trainable models may be affected. As an example, spectral data obtained with different spectrometer apparatuses (which have different instrument resolutions) typically provides such different spectral data. In terms of modeling, this technical challenge can only be overcome by specifically training the trainable model to cope with the differences between different spectrometer apparatuses. However, as the number of spectrometer apparatuses for which the trainable model needs to be used increases, this procedure becomes increasingly infeasible. There is a need for a global, use-case independent calibration and correction scheme at the level of individual spectrometer apparatuses that enables the resulting spectral data population to be homogenized to the extent that the trainable model can produce accurate results across the entire spectrometer apparatus population.

[0007] J.C. Weatheran et al., “Adapting Raman Spectra from Laboratory Spectrometers to Portable Detection Libraries,” APPLIED SPECTROSCOPY, Vol. 67, No. 2, 2013, which describes processing Raman spectral data collected using a high-resolution laboratory spectrometer into a format suitable for import into a user library for a 1064 nm DeltaNu first-generation field-deployable spectrometer prototype. The two laboratory systems used were a 1064 nm Bruker Fourier transform (FT)-Raman spectrometer and a 785 nm Kaiser dispersive spectrometer.

[0008] D. Kakkad et al., “HARMON!: Characterising the line spread function with a tunable Fabry-Perot etalon,” Proc. SPIE 11451, Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation IV, 114515W, December 13, 2020, which describes a tunable Fabry-Perot design for characterising the line spread function (LSF) of the High Angular Resolution Monolithic Optical and Near-infrared Integral Field Spectrograph (HARMONI).

[0009] E. Emsellem et al., "The PHANGS-MUSE survey: Probing the chemo-dynamical evolution of disc galaxies", A&A [Astronomy and Astrophysics], Vol. 659, March 2022, A191, which describes the PHANGS-MUSE survey, a project that mapped 19 nearby massive star-forming disc galaxies using the MUSE integral field spectrometer (IFS) of the ESO VLT.

[0010] US2007 / 0046933 A1 describes a spectroscopic analysis method in which a sample is stimulated to produce at least one test spectral line or spectrum of a component contained in the sample, and transmitted and / or emitted electromagnetic radiation is used to create the test spectral line or spectrum.

[0011] EP 0 982 582 A1 describes suppressing the influence of unwanted components (such as H20 and C02) in spectral data measured by a spectrometer. The data is modified so that its resolution matches that of the instrument, the data is filtered to account for the interference effects of the sample, and this data is subtracted from the measured sample spectrum to provide corrected output data.

[0012] US 5,303,165 A describes a spectroscopic instrument that exhibits an intrinsic profile for sharp spectral lines and produces profile data for narrow spectral lines.

[0013] Problem to be solved

[0014] Accordingly, there is a desire to provide methods and apparatuses that at least partially address the above-described technical challenges regarding the calibration of spectrometer devices. Specifically, a method and system for calibrating spectrometer devices in a batch of spectrometer devices should be proposed that provides global and use-case-independent calibration, thereby ensuring high accuracy and reliability of the results of the spectrometer devices. Summary of the Invention

[0015] This problem is solved by a method and system for calibrating spectrometer devices in a batch of spectrometer devices, a computer program, and a computer-readable storage medium having the features of the independent claims. Advantageous embodiments that can be implemented independently or in any arbitrary combination are listed in the dependent claims and throughout the specification.

[0016] As used herein, the terms "having", "including", or "comprising", or any arbitrary grammatical variations thereof, are used in a non-exclusive manner. These terms can either refer to a situation where no additional features exist in the entity described in the context other than the features introduced by these terms, or to a situation where one or more additional features exist. As an example, the statements "A has B", "A includes B", and "A comprises B" can either refer to a situation where no other elements exist in A other than B (i.e., the situation where A consists only and solely of B), or to a situation where one or more additional elements (such as element C, elements C and D, or even additional elements) exist in entity A in addition to B.

[0017] Further, it should be noted that the terms "at least one", "one or more", or similar expressions indicating that a feature or element can occur once or more than once typically are used only once when introducing the corresponding feature or element. In most cases, when referring to the corresponding feature or element, the expressions "at least one" or "one or more" are not repeated, but in fact, the corresponding feature or element may occur once or more than once.

[0018] Further, as used herein, the terms "preferably", "more preferably", "particularly", "more particularly", "specifically", "more specifically", or similar terms are used in connection with optional features without restricting the possibility of alternatives. The features introduced by these terms are optional features and are not intended to limit the scope of the claims in any way. As those skilled in the art will recognize, the present invention can be implemented by using alternative features. Similarly, features introduced by "in an embodiment of the present invention" or similar expressions are intended to be optional features without any limitation on alternative embodiments of the present invention, without any limitation on the scope of the present invention, and without any limitation on the possibility of combining the features introduced in this way with other optional or non-optional features of the present invention.

[0019] In a first aspect of the present invention, a method for calibrating a spectrometer device in a batch spectrometer device is disclosed.

[0020] As used herein, the term "spectrometer device" is a broad term and will be given its ordinary and customary meaning to a person of ordinary skill in the art and is not limited to a special or custom meaning. Specifically, the term can refer to, but is not limited to, a device capable of optically analyzing at least one sample to generate at least one piece of information about at least one spectral characteristic of the sample. Specifically, the term can refer to a device capable of recording the signal intensity of corresponding wavelengths of a spectrum or a partition thereof (such as a wavelength interval), wherein the signal intensity can preferably be provided in the form of an electrical signal, which can be used for further evaluation. Optical elements specifically including at least one wavelength selection element (such as an optical filter and / or a dispersive element) can be used to separate incident light into a spectrum having constituent wavelength components, and the respective intensities of these constituent wavelength components are determined by using a detector device. In addition, additional optical elements that can be designed to receive incident light and transmit the incident light to the optical elements can be used. Generally, the spectrometer device can operate in a reflection mode and / or can operate in a transmission mode. For possible embodiments of the spectrometer device, reference is made to the description of the spectrometer device outlined in further detail below.

[0021] As used herein, the term "calibrating" (the process is also referred to as "calibration") is a broad term and will be given its ordinary and customary meaning to a person of ordinary skill in the art and is not limited to a special or custom meaning. The term can specifically refer to, but is not limited to, the process of determining, correcting, and adjusting at least one of the measurement inaccuracies at a spectrometer device. The result of the calibration process (which is typically also referred to as "a calibration information") can also be or include at least one piece of information regarding the result of the calibration process, such as a calibration function, a calibration factor, a calibration matrix, etc., for example, for converting one or more measured values into one or more calibrated values or "true" values. As an example, the measurement inaccuracy may stem from the uncertainty present in wavelength determination and / or from the internal and / or external interference generated in the measurement signal of the spectrometer device. Calibrating a spectrometer device can include at least one of wavelength calibration, stray light calibration, dark current calibration, spectral resolution testing. Calibration (specifically each calibration) can include at least a two-step process, where, in the first step, information regarding the deviation of the measurement signal of the spectrometer device from a known standard is determined, and where, in the second step, this information is used to correct and / or adjust the measurement signal of the spectrometer device in order to reduce, minimize, and / or eliminate the deviation. Calibration can include applying the calibration information to, for example, the measurement signal and / or the measured spectrum of the spectrometer device. Calibration of a spectrometer device can improve and / or maintain the accuracy of the measurements performed using the calibrated spectrometer device. Alternatively or additionally, calibration can include preparing the measurement signal and / or the measured spectrum of the spectrometer device such that the measurement signal and / or the measured spectrum can be used for further analysis and / or evaluation, such as by preparing the measurement signal and / or the measured spectrum as input data for one or more trainable models for analyzing the measurement signal and / or the measured spectrum. Calibration can ensure that the measurement signal and / or the measured spectrum are suitable for analysis by the trainable model in order to provide accurate results.

[0022] Calibration of a spectrometer device can specifically be performed at the manufacturer's site of the spectrometer device manufacturer. However, calibration can also be performed on-site, such as after installing the spectrometer device at the point of use and / or for maintenance purposes.

[0023] As used herein, the term "batch" is a broad term and will be given its ordinary and customary meaning to a person of ordinary skill in the art and is not limited to a special or custom meaning. The term can specifically refer to, but is not limited to, multiple spectrometer devices manufactured in a common manufacturing process. The common manufacturing process can include a series of manufacturing steps, where the series of manufacturing steps results in multiple assembled spectrometer devices. The common manufacturing process can specifically refer to a co-manufacturing process in terms of time and / or manufacturing steps. The batch spectrometer devices can be manufactured in a timely overlapping manner. Alternatively or additionally, the batch spectrometer devices can be manufactured in subsequent manufacturing processes, where the subsequent manufacturing processes include the same series of manufacturing steps. The term "batch spectrometer devices" can also be referred to as "a group of spectrometer devices" or any grammatical variant thereof.

[0024] The spectrometer device includes at least one detector device. Specifically, when calibrating the spectrometer device, it may be necessary and possible to calibrate the detector device included in the spectrometer device. As used herein, the term "detector device" is a broad term and will be given its ordinary and customary meaning to a person of ordinary skill in the art and is not limited to a special or custom meaning. The term can specifically refer to, but is not limited to, any device or combination of devices capable of recording and / or monitoring incident light. The detector device can respond to incident illumination and can be configured to generate an electrical signal indicative of the illumination intensity. The detector device can be sensitive in one or more of the visible spectral range, ultraviolet spectral range, or infrared spectral range (specifically the near-infrared spectral range (NIR)). The detector device can specifically be or can include at least one optical sensor, e.g., an optical semiconductor sensor. As an example, specifically, in the case where the detector device is sensitive in the infrared spectral range (such as in the near-infrared spectral range), the semiconductor sensor can be or can include at least one semiconductor sensor at least one of whose materials is selected from the group consisting of: Si, PbS, PbSe, Ge, InGaAs, extended InGaAs, InSb, or HgCdTe. As an example, the detector device can include at least one photodetector, such as at least one CCD or CMOS device. The detector device can specifically include at least one detector array, the at least one detector array including a plurality of pixelated sensors, where each pixelated sensor is configured to detect at least a portion of at least one component wavelength component.

[0025] The detector device includes at least one optical element configured to separate incident light into a spectrum having constituent wavelength components. As used herein, the term "optical element" is a broad term and will be given its ordinary and customary meaning to one of ordinary skill in the art and is not limited to a special or custom meaning. The term can specifically refer to, but is not limited to, any element or combination of elements suitable for performing one or more of transmission, reflection, deflection, or scattering of light in a wavelength-dependent manner. The optical element can specifically be further configured to transmit the spectrum onto the detector device after separating the incident light into a spectrum having constituent wavelength components. Specifically, wavelength-dependent transmission, reflection, deflection, or scattering of the incident light at the optical element can cause spatial separation of the constituent wavelength components of the spectrum, which can be transmitted directly or indirectly onto the detector device.

[0026] As used herein, the term "light" is a broad term and will be given its ordinary and customary meaning to one of ordinary skill in the art and is not limited to a special or custom meaning. The term can specifically refer to, but is not limited to, a portion of electromagnetic radiation that is commonly referred to as the "optical spectral range" and includes one or more of the visible spectral range, the ultraviolet spectral range, and the infrared spectral range. The term "ultraviolet spectrum" or "UV" generally refers to electromagnetic radiation having a wavelength of 1 nm to 380 nm, preferably 100 nm to 380 nm. The term "visible" generally refers to wavelengths of 380 nm to 760 nm. The term "infrared" or "IR" generally refers to wavelengths of 760 nm to 1000 μm, where wavelengths of 760 nm to 3 μm are commonly referred to as "near infrared" or "NIR", wavelengths of 3 μm to 15 μm are commonly referred to as "mid infrared" or "MidIR", and wavelengths of 15 μm to 1000 μm are referred to as "far infrared" or "FIR".

[0027] As used herein, the term "spectrum" is a broad term and will be given its ordinary and customary meaning to one of ordinary skill in the art and is not limited to a special or custom meaning. The term can specifically refer to, but is not limited to, a portion of the optical spectral range, particularly the IR spectral range (especially at least one of the NIR spectral range or the MidIR spectral range), studied by a spectrometer device. Each part of the spectrum can be constituted by an optical signal defined by a signal wavelength and a corresponding signal intensity. As used herein, the term "constituent wavelength component" is a broad term and will be given its ordinary and customary meaning to one of ordinary skill in the art and is not limited to a special or custom meaning. The term can specifically refer to, but is not limited to, an optical signal that forms part of a spectrum. Specifically, the optical signal can include a signal intensity corresponding to a respective wavelength or wavelength interval.

[0028] The detector device further includes a plurality of photosensitive elements, wherein each photosensitive element is configured to receive at least a part of one of these component wavelength components and to generate a corresponding detector signal based on the illumination of the corresponding photosensitive element by at least a part of the corresponding component wavelength component.

[0029] As used herein, the term "photosensitive element" is a broad term and will be given its ordinary and conventional meaning to those of ordinary skill in the art and is not limited to a special or custom meaning. Specifically, the term may refer to, but is not limited to, individual optical sensors included in the detector device, wherein each optical sensor has at least one photosensitive area configured to record the light response of the photosensitive element by generating at least one output signal, the at least one output signal depending on the intensity of a part of one of the component wavelength components incident on the specific photosensitive area. The at least one photosensitive area included in each individual optical sensor may in particular be a single uniform area designated to receive the incident light on the photosensitive area. The at least one output signal may in particular be used as a detector signal and may preferably be provided to an external evaluation unit for further evaluation.

[0030] As used herein, the term "detector signal" is a broad term and will be given its ordinary and conventional meaning to those of ordinary skill in the art and is not limited to a special or custom meaning. Specifically, the term may refer to, but is not limited to, a signal generated by at least one detector, specifically an output signal of at least one photosensitive element. The at least one output signal may be selected from at least one of an electrical signal and an optical signal. The at least one output signal may be an analog signal and / or a digital signal. The output signals of adjacent photosensitive elements may be generated simultaneously or in a temporally consecutive manner. For example, during a line scan or a row scan, it may be feasible to generate a series of output signals corresponding to a series of photosensitive elements that may be arranged in a row. Further, each photosensitive element may preferably be an active pixel sensor, which may be adapted to amplify the output signal before providing the output signal as a detector signal to an external evaluation unit. For this purpose, the photosensitive element may include one or more signal processing means, such as one or more filters and / or analog-to-digital converters, for processing and / or preprocessing the electrical signal.

[0031] The method includes the following steps, by way of example, which may be performed in a given order. However, it should be noted that different orders are also possible. Further, one or more method steps may be performed once or repeatedly. Further, two or more method steps may be performed simultaneously or in a timely overlapping manner. The method may include additional method steps not listed.

[0032] The method includes the following steps:

[0033] a) at least one system characterization step, the at least one system characterization step including determining a line spread function at a corresponding wavelength by comparing at least one spectrum measured by using a spectrometer device with at least one reference spectrum;

[0034] b) at least one resolution homogenization step, the at least one resolution homogenization step including converting the resolution of the line spread function to a predefined target resolution for the corresponding wavelength for each wavelength, wherein the target resolution for each wavelength is a predefined target batch resolution value for the corresponding wavelength.

[0035] As used herein, the term "system characterization" is a broad term and will be given its ordinary and customary meaning to a person of ordinary skill in the art and is not limited to a special or custom meaning. The term can specifically refer to, but is not limited to, the process of determining one or more system characteristics of a spectrometer device. The system characterization step can include determining system characteristics related to spectral data obtained by using a spectrometer device. For example, the system characteristics can include one or more of spectral resolution, stray light effects, and / or detector characteristics. The system characterization step can be performed with each spectrometer device in a group of spectrometer devices. The system characterization step can determine one or more system characteristics of each spectrometer device in the group of spectrometer devices. The system characteristics can vary for the spectrometer devices in the group of spectrometer devices. The spectrometer device with the lowest performance (e.g., the lowest spectral resolution of a particular spectrometer device) can be used as the lower boundary for the following homogenization steps. The system characterization step can be specifically performed to estimate an instrument line spread function, which provides an estimate of the spectral resolution as a function of wavelength. The system characterization step can include determining system characteristics by analyzing spectral data obtained by using a spectrometer device. For example, the characterization step can specifically include analyzing spectral data obtained by using a spectrometer device (such as analyzing a spectrum measured by using a spectrometer device and a reference spectrum) to obtain the system characteristics of the spectrometer device.

[0036] As used herein, the term "reference spectrum" is a broad term and will be given its ordinary and customary meaning to one of ordinary skill in the art and is not limited to a special or custom meaning. The term can specifically refer to, but is not limited to, a spectrum obtained by measuring a reference object with a reference spectrometer device, specifically the spectrum as defined above. The reference object can be an object having known spectral characteristics (such as known reflection and / or transmission characteristics). The reference spectrometer device for measuring the reference object can be a high-resolution spectrometer device. The reference spectrum can be obtained prior to performing the method. The reference spectrum can be provided by the manufacturer of the reference object and / or by the manufacturer of the spectrometer device. As an example, the reference spectrum can be measured by the manufacturer of the reference object, who provides the reference object and the reference spectrum. Alternatively or additionally, the reference spectrum can be measured by the manufacturer of the spectrometer device by measuring the reference object with a high-resolution spectrometer device. The reference spectrum can be stored in a database and can be retrieved when performing step a).

[0037] As used herein, the term "line spread function" is a broad term and will be given its ordinary and customary meaning to one of ordinary skill in the art and is not limited to a special or custom meaning. The term can specifically refer to, but is not limited to, information describing the response distribution of a photosensitive element to incident light having a specific wavelength. Specifically, the line spread function can describe the relationship between the detector signal of each photosensitive element and a fixed monochromatic excitation. The line spread function can be used to estimate the spectral resolution of a spectrometer device as a function of wavelength. Specifically, the line spread function can describe the response distribution of multiple photosensitive elements to incident light having a specific wavelength. For a specific wavelength, the line spread function can include a discrete response distribution and / or a continuous response distribution of multiple photosensitive elements to incident light having a specific wavelength. The response distribution can be used to estimate the spectral resolution of the spectrometer at a specific wavelength, such as by fitting one or more resolution functions to the distribution. The line spread function can be determined for at least two specific wavelengths within the entire wavelength range of the spectrometer device. The line spread function over the entire wavelength range can be obtained by interpolating between the line spread functions at specific wavelengths, specifically between the spectral resolutions estimated by the line spread functions.

[0038] As used herein, the term "resolution" (also referred to as "spectral resolution") is a broad term and will be given its ordinary and customary meaning to one of ordinary skill in the art and is not limited to a special or custom meaning. The term can specifically refer to, but is not limited to, a measure of the ability of a spectrometer to resolve features in a measured spectrum. Specifically, the resolution can be the minimum wavenumber, wavelength, or frequency difference between two lines that can be distinguished in a spectrum.

[0039] The system characterization step can include:

[0040] a1) irradiating a spectrometer device by using at least one broadband light source through at least one optical interferometer;

[0041] a2) for a plurality of photosensitive elements, determining a plurality of detector signals according to the irradiation situation through the optical interferometer in step a1); and

[0042] a3) determining a line spread function according to the plurality of detector signals.

[0043] As used herein, the term "broadband light source" is a broad term and will be given its ordinary and conventional meaning to those of ordinary skill in the art and is not limited to a special or custom meaning. Specifically, this term can refer to, but is not limited to, a device that emits light in a wide spectral range (such as light with a spectral width of at least 5 nm, specifically at least 10 nm (for example, a spectral width of 10 nm to 3000 nm)). The wide spectral range of the broadband light source can include at least one of the visible spectral range, the ultraviolet spectral range, and the infrared spectral range. The light for the typical purposes of the present invention can particularly include light in the IR spectral range, specifically within at least one of the NIR spectral range or the MidIR spectral range, more specifically light with a wavelength of 1 μm to 5 μm, even more specifically 1 μm to 3 μm, and can include light within the visible spectral range, specifically light with a wavelength of 380 nm to 760 nm. For example, the broadband light source can include a thermal emitter that emits light within the visible spectral range, NIR, and MidIR (such as 600 nm to 3000 nm). By way of example, the broadband light source can include at least one of the following: incandescent lamp; blackbody radiator; electric filament; light-emitting diode.

[0044] As used herein, the term "optical interferometer" is a broad term and will be given its ordinary and conventional meaning to those of ordinary skill in the art and is not limited to a special or custom meaning. Specifically, this term can refer to, but is not limited to, a device or combination of devices that enables light, specifically light within a spectral range, to be superimposed to produce an interference effect on the superimposed light. For example, the optical interferometer can be configured to divide incident light into at least two light beams, and further configured to cause a phase shift of the divided light beams relative to each other. The optical interferometer can further be configured to combine these phase-shifted light beams such that these light beams are superimposed on each other and interfere. The optical interferometer can include at least one interferometer selected from the group consisting of: Michelson interferometer; Fabry - Perot interferometer; cube corner interferometer.

[0045] In step a1), the main frequency of the optical interferometer, specifically the main transmission frequency and / or the main reflection frequency of the optical interferometer, can vary within a pre-determined spectral range. In step a2), a plurality of detector signals can be determined based on the main frequency of the optical interferometer. In step a3), the line spread function can be determined by comparing the main frequency of the optical interferometer, specifically the main transmission frequency and / or the main reflection frequency of the optical interferometer, with at least one of the pixel positions and identification numbers of the intensity peaks associated with the main frequency in the plurality of detector signals generated by a plurality of photosensitive elements. As used herein, the term "pixel position" is a broad term and will be given its ordinary and conventional meaning to those of ordinary skill in the art and is not limited to a special or custom meaning. Specifically, the term can refer to, but is not limited to, any one of the position information of the photosensitive element in the detector device. The pixel information can describe the position of the photosensitive element in the detector device by using one or more of absolute position information and relative position information (specifically in one, two, or even three dimensions). As used herein, the term "identification number" is a broad term and will be given its ordinary and conventional meaning to those of ordinary skill in the art and is not limited to a special or custom meaning. Specifically, the term can refer to, but is not limited to, a piece of numerical or alphanumerical information that uniquely identifies each photosensitive element included in the detector device. For example, the photosensitive elements of the detector device can be numbered according to the order of appearance of the detector device. However, other options for identifying the photosensitive elements in the detector device are also feasible.

[0046] As an example, the optical interferometer can include at least one beam splitting device for splitting the incident light into at least two illumination paths. The optical interferometer can further include at least one scanning mirror on the first illumination path and at least one stationary mirror on the second illumination path. In this method, specifically in steps a1) and a2), the scanning mirror can move along the first illumination path, wherein the stationary mirror can remain stationary. Specifically, in step a2), a plurality of detector signals can be determined for a plurality of positions of the scanning mirror on the first illumination path. The plurality of positions of the scanning mirror can be different from each other. Step a3) can further include associating the plurality of detector signals with the plurality of positions of the scanning mirror. Specifically, in step a3), associating the plurality of detector signals with the plurality of positions of the scanning mirror can be used to determine the line spread function.

[0047] Step a3) may include processing the plurality of detector signals determined in step a2) to obtain a plurality of processed detector signals. Determining the line spread function in step a3) may include determining the line spread function based on the plurality of processed detector signals. Processing the plurality of detector signals may specifically include transforming the plurality of detector signals. As an example, the plurality of detector signals may be transformed by using at least one Fourier transform.

[0048] The system characterization step including steps a1) to a3) may include feeding light from an optical interferometer having at least one spectrally continuous broadband light source to a spectrometer device and using a detector device of the spectrometer device to form a Fourier transform spectrometer. The resulting interferogram (i.e., the measured intensity as a function of the mirror position of the interferometer) may be used to calculate the line spread function of the spectrometer device at each wavelength position.

[0049] Alternatively or additionally, the system characterization step may include:

[0050] ai) irradiating the spectrometer device with monochromatic light sources, the central wavelengths of which cover the wavelength range of the spectrometer device to be calibrated;

[0051] aii) determining the line spread function by comparing the known spectra of these monochromatic light sources with the spectra measured by using the spectrometer device.

[0052] As used herein, the term "monochromatic light source" is a broad term and will be given its ordinary and conventional meaning to a person of ordinary skill in the art and is not limited to a special or custom meaning. The term may specifically refer to, but is not limited to, a device that emits light having a single wavelength or within a spectral range of no more than 100 nm, specifically at least no more than 10 nm, more specifically no more than 5 nm. The monochromatic light source may be configured to emit light within at least one of the visible spectral range, the ultraviolet spectral range, and the infrared spectral range. As an example, the monochromatic light source may include a continuous emitter (such as a broadband light source) combined with a bandpass filter, or a monochromatic emitter (such as a laser, etc.). The intrinsic spectral width of the monochromatic light source may be comparable to the line spread function at the corresponding wavelength. The monochromatic light source may specifically include a plurality of monochromatic light sources.

[0053] Step aii) may include broadening the known spectrum of a monochromatic light source by performing kernel convolution using a theoretical line spread function. Step aii) may specifically include adjusting the parameters of the theoretical kernel until the broadened spectrum of the monochromatic light source matches the measured spectrum. The adjusted kernel parameters may be used to approximate the line spread function at that wavelength. The theoretical kernel may be at least one kernel selected from the group consisting of: a Gaussian kernel having only one free parameter; a Lorentzian profile; a Moffat profile; or a Voigt profile; an asymmetric kernel. Other kernels may also be feasible. However, for example, the theoretical kernel may be a Gaussian kernel having only one free parameter. In this example, the free parameter of the Gaussian kernel may be the full width at half maximum (FWHM).

[0054] The system characterization step including steps ai) and aii) may include using a plurality of monochromatic light sources, the center wavelengths of which span the entire wavelength range of the spectrometer device to be characterized. The center wavelength of the monochromatic light source may represent the wavelength having the highest intensity in the spectrum of the monochromatic light source. For example, such a monochromatic light source may be implemented by using a continuous emitter in combination with a bandpass filter and / or by using a monochromatic emitter (such as a laser, etc.). The intrinsic spectral width of the source may preferably be less than the line spread function of the spectrometer device at the corresponding wavelength. By comparing the known spectrum of the light fed into the spectrometer device with the response of the spectrometer device to this irradiation, the line spread function of the spectrometer device at the center wavelength of the monochromatic light source can be determined. For example, determining the line spread function may include performing kernel convolution using a theoretical line spread function to broaden a known high-resolution spectrum. The parameters of the theoretical kernel may be adjusted until the broadened reference spectrum matches the spectrum obtained with the spectrometer device to be characterized. The best-fit function parameters may be used to theoretically approximate the line spread function at that wavelength. The theoretical kernel may be a Gaussian kernel having only one free parameter (specifically the FWHM). Other possible kernel types may include a Lorentzian profile, a Moffat profile, or a Voigt profile, where the Moffat profile and the Voigt profile may include two free parameters. However, other, especially asymmetric, kernels are also possible. The line spread function varying with wavelength over the entire spectral range may be obtained by interpolating between the locally estimated fit parameters of different monochromatic sources.

[0055] Alternatively or additionally, the system characterization step may include:

[0056] aa) irradiating at least one reference object by using at least one broadband light source;

[0057] ab) determining the line spread function by comparing the known spectrum of the reference object with the spectrum measured by using the spectrometer device, wherein the known spectrum of the reference object is pre-determined by using at least one high-resolution spectrometer.

[0058] Step ab) may include broadening the known spectrum of the reference object by performing kernel convolution using a theoretical line spread function. Step ab) may include adjusting the parameters of the theoretical kernel until the broadened spectrum of the reference object matches the measured spectrum. The adjusted kernel parameters may be used to approximate the line spread function at that wavelength. The theoretical kernel may be at least one kernel selected from the group consisting of: a Gaussian kernel having only one free parameter; a Lorentzian profile; a Moffat profile; or a Voigt profile; an asymmetric kernel.

[0059] Step ab) may include directly comparing the known spectrum of the reference object with the spectrum measured in the signal space by using a spectrometer device and / or comparing at least one derivative of the known spectrum of the reference object with at least one derivative of the spectrum measured by using a spectrometer device, specifically comparing the first-order derivative, second-order derivative, and / or higher-order derivatives of these spectra.

[0060] The system characterization step including steps aa) and ab) may include using one or more reference objects, the intrinsic spectra of which may be known, specifically known at a higher resolution, and may be pre-measured using a high-resolution spectrometer. The higher resolution may refer to a situation where the resolution of the intrinsic spectrum is higher than the resolution of the spectrometer device to be characterized. By determining the spectra of these reference objects with the spectrometer device to be characterized and comparing the response of the spectrometer device, specifically the response of a plurality of photosensitive elements, with the intrinsic spectra, the line spread function of the spectrometer device at each wavelength position may be determinable. The mathematical processing may include convolution with a theoretical kernel, as outlined above. For example, a Gaussian kernel may be used to determine the line spread function. The comparison may be performed in the signal space or using its higher derivatives. This may have the advantage that a constant offset that is not affected by the resolution difference (such as a constant offset due to stray light in the spectrometer system) may not affect the loss function used to find the optimal line spread function.

[0061] Further, as outlined above, the method may include at least one resolution homogenization step. As used herein, the term "resolution homogenization" is a broad term and will be given its ordinary and customary meaning to a person of ordinary skill in the art and is not limited to a special or custom meaning. The term may specifically refer to, but is not limited to, the process of unifying the system characteristics of spectrometer devices in a batch spectrometer device. Specifically, the resolution homogenization step may include unifying the system characteristics of the spectrometer device determined in the system characterization step. As a result of the resolution homogenization step, the system characteristics of the spectrometer device may be the same as those of each other spectrometer device in the batch spectrometer device. The resolution homogenization step may specifically include unifying the spectral resolution of the spectrometer devices in the batch spectrometer device. The resolution homogenization step may include using the in-state of the line spread function of each previously determined spectrometer device and computationally converting the in-state of the line spread function to a target state. The in-state of the line spread function may refer to the state of the line spread function determined in step a), specifically indicating the spectral resolution of the spectrometer device at a specific wavelength. The in-state may specifically be the individual state of the spectrometer device. For different spectrometer devices in the batch spectrometer device, the in-state may be different.

[0062] As outlined above, the resolution homogenization step includes: for each wavelength, converting the resolution of the line spread function to a predefined target resolution for the corresponding wavelength, wherein the target resolution for each wavelength is a predefined target batch resolution value for the corresponding wavelength.

[0063] As used herein, the term "target resolution" is a broad term and will be given its ordinary and customary meaning to a person of ordinary skill in the art and is not limited to a special or custom meaning. The term may specifically refer to, but is not limited to, the resolution defining the nominal value of the resolution homogenization step, specifically the resolution as defined above. The target resolution may be wavelength-dependent. The target resolution may be defined for each wavelength in the entire wavelength range of the spectrometer device. The target resolution may be a fixed target resolution. For each spectrometer device in the batch spectrometer device, the target resolution may be the same. The target resolution may be lower than the resolution of an individual spectrometer device in the group. This may be desirable because a narrower line spread function, specifically the resolution of the line spread function, can be broadened to a wider resolution, but not vice versa.

[0064] As used herein, the term "target batch resolution value" is a broad term and will be given its ordinary and customary meaning to one of ordinary skill in the art and is not limited to a special or custom meaning. Specifically, this term can refer to, but is not limited to, the same target resolution for each spectrometer device in a batch spectrometer device.

[0065] The target resolution and the target batch resolution value are predefined. As used herein, the term "predefined" can refer to, but is not limited to, a situation where the target resolution and / or the target batch resolution value can be known and / or determined before performing the method. In other words, the target resolution and / or the target batch resolution value can be defined before performing the method.

[0066] Predefined target batch resolution value A λ,target can be selected such that the conversion resolution A for the corresponding wavelength of the spectrometer device λ,conv satisfies A λ,conv ≤A λ,target .

[0067] Converting the corresponding resolution A of the line spread function λ,meas to the predefined target resolution can include convolving the measured spectrum with at least one kernel whose width is described by a quadratic subtraction .

[0068] For example, the line spread function can be a Gaussian function having a measured full width at half maximum λ at a wavelength FWHM λ , and the predefined target batch resolution value can be a predefined full width at half maximum FWHM λ,target . This conversion can include convolving the measured spectrum with a Gaussian kernel whose width is described by a quadratic subtraction .

[0069] In this example, the predefined target batch resolution value can be the target resolution value for the entire group. The homogenized spectral data points S at a wavelength λ λ can be obtained by broadening or convolving the measured spectrum with a Gaussian kernel having a width of FWHM λ,conv . In this way, all FWHM of all spectrometer devices in the batch spectrometer device that satisfy FWHM λ <FWHM λ,target can be homogenized to the same resolution FWHM λ . λ,target

[0070] In another aspect of the present invention, a system for calibrating a spectrometer device in a batch spectrometer device is disclosed. The system includes a spectrometer device, which includes at least one detector device. The detector device includes at least one optical element configured to separate incident light into a spectrum having component wavelength components. The detector device further includes a plurality of photosensitive elements. Each photosensitive element is configured to receive at least a portion of one of these component wavelength components and to generate a corresponding detector signal based on the illumination of the corresponding photosensitive element by at least a portion of the corresponding component wavelength component. The system further includes at least one evaluation unit. The evaluation unit is configured to perform a method for calibrating a spectrometer device in a batch spectrometer device according to the present invention (such as according to any one of the embodiments disclosed above and / or any one of the embodiments disclosed in further detail below).

[0071] For the definition and possible embodiments of the system or parts thereof, reference is made to the definitions and embodiments described with respect to the method for calibrating a spectrometer device in a batch spectrometer device.

[0072] As used herein, the term "system" is a broad term and will be given its ordinary and conventional meaning to a person of ordinary skill in the art and is not limited to a special or custom meaning. Specifically, the term can refer to, but is not limited to, any set of interacting or interdependent component parts that form a whole. Specifically, these components can interact with each other in order to achieve at least one common function. The components of the system can be processed independently, or can be coupled or connectable. For example, the system can be a single unit, where, for example, the spectrometer device and the evaluation unit can form a coupled unit or a connectable unit. Alternatively or additionally, the system can be a distributed system, where, for example, the spectrometer device and the evaluation unit can be processed independently of each other, but can communicate with each other via a communication network. As an example, the evaluation unit can form part of a cloud computer network, where the spectrometer device can be configured to communicate with the evaluation unit in the cloud computer network.

[0073] As used herein, the term "evaluation unit" is a broad term and will be given its ordinary and customary meaning to a person of ordinary skill in the art and is not limited to a special or custom meaning. Specifically, the term can refer to, but is not limited to, any logic circuit configured to perform basic operations of a computer or system, and / or generally refers to a device configured to perform computational or logical operations. In particular, the evaluation unit can be configured to process basic instructions that drive a computer or system. As an example, the evaluation unit can include at least one arithmetic logic unit (ALU), at least one floating point unit (FPU) (such as a math coprocessor or a digital coprocessor), multiple registers (specifically registers configured to provide operands to the ALU and store operation results), and a memory (such as L1 and L2 cache memories). In particular, the processor can be a multi-core processor. Specifically, the evaluation unit can be or can include a central processing unit (CPU). For example, the evaluation unit can include one or more processors. Additionally or alternatively, the evaluation unit can be or can include a microprocessor. Specifically, the elements of the evaluation unit can be contained in a single integrated circuit (IC) chip. Additionally or alternatively, the evaluation unit can be or can include one or more application specific integrated circuits (ASICs) and / or one or more field programmable gate arrays (FPGAs) and / or one or more tensor processing units (TPUs) and / or one or more chips (such as dedicated machine learning optimized chips, etc.). The evaluation unit can be specifically configured to perform one or more evaluation operations, specifically such as one or more operations performed in steps a) and / or b) of the method described in further detail above, for example, by software programming. The evaluation unit can be configured to exchange data and / or control commands unidirectionally and / or bidirectionally with other elements of the system, specifically with the detector device. Specifically, the evaluation unit can be configured to receive a plurality of detector signals from the detector device.

[0074] The evaluation unit can specifically include at least one data storage unit configured to store at least one of a reference spectrum and a target resolution. Alternatively or additionally, the evaluation unit can include at least one retrieval interface configured to retrieve at least one of a reference spectrum and a target resolution, specifically for retrieving at least one of a reference spectrum and a target resolution from a cloud computer network.

[0075] As used herein, the term "data storage unit" is a broad term and will be given its ordinary and customary meaning to a person of ordinary skill in the art and is not limited to a special or custom meaning. Specifically, the term can refer to, but is not limited to, any memory device configured to store data. Specifically, the data storage unit can be an electronic memory device, a magnetic memory device, and / or a mechanical memory device. The data storage unit can be further configured to store data, specifically to store data in an organized manner, such as stored in a database, more specifically stored in at least one database record.

[0076] As used herein, the term "retrieval interface" is a broad term and will be given its ordinary and customary meaning to a person of ordinary skill in the art and is not limited to a special or custom meaning. Specifically, the term can refer to, but is not limited to, an element or device configured to retrieve information (such as for the purpose of one-way or two-way exchange of information, such as for the exchange of one or more data or commands). For example, the retrieval interface can be configured to share information stored in the data storage with another device, specifically with an evaluation unit. The retrieval interface can include a data interface, such as a wireless and / or wired data interface.

[0077] The system can further include at least one broadband light source and at least one optical interferometer, both of which are arranged to irradiate a spectrometer device through the optical interferometer using the broadband light source. The broadband light source and / or the optical interferometer can be implemented as defined above in the context of the method. In this configuration, the system can be configured to perform steps a1) to a3) of the method for calibrating a spectrometer device in a batch of spectrometer devices according to the present invention (such as according to any one of the embodiments disclosed above and / or any one of the embodiments further disclosed in detail below).

[0078] Alternatively or additionally, the system can further include at least one reference object and at least one broadband light source. In this configuration, the system can be configured to perform steps aa) and ab) of the method for calibrating a spectrometer device in a batch of spectrometer devices according to the present invention (such as according to any one of the embodiments disclosed above and / or any one of the embodiments further disclosed in detail below). As described above, the broadband light source can include at least one of the following: incandescent lamp; blackbody radiator; electric filament; light-emitting diode.

[0079] Alternatively or additionally, the system may further include monochromatic light sources, the center wavelengths of which span the wavelength range of the spectrometer device to be calibrated. In such a configuration, the system may be configured to perform steps ai) and aii) of the method for calibrating a spectrometer device in a batch of spectrometer devices according to the present invention (such as according to any one of the embodiments disclosed above and / or any one of the embodiments disclosed in further detail below).

[0080] The optical element(s) may include at least one wavelength-selective element. As used herein, the term "wavelength-selective element" is a broad term and will be given its ordinary and conventional meaning to a person of ordinary skill in the art and is not limited to a special or custom meaning. Specifically, the term may refer to, but is not limited to, an optical element configured to selectively transmit light of different wavelengths. Specifically, the wavelength-selective element may be configured to transmit an incident light beam, whereby the spectral composition of the incident light may be modified upon transmission. The modification of the transmitted light may include one or more of the following: spatially separating light of different wavelengths; attenuating light of different wavelengths. For example, the wavelength-selective element may be configured to selectively transmit light within a specific wavelength range while absorbing, filtering, and / or interfering with the remaining light. The wavelength-selective element may include at least one element selected from the group consisting of: a prism; a grating; a linear variable filter; an optical filter.

[0081] The detector device may include a plurality of photosensitive elements arranged in a linear array. The photosensitive elements of the linear array may include from 10 to 1000 photosensitive elements, specifically from 100 to 500 photosensitive elements, specifically from 200 to 300 photosensitive elements, more specifically 256 photosensitive elements, and most specifically 128 photosensitive elements.

[0082] Each photosensitive element may include at least one element selected from the group consisting of: a pixelated inorganic camera element, specifically a pixelated inorganic camera chip, more specifically a CCD chip or a CMOS chip; a monochromatic camera element, specifically a monochromatic camera chip; at least one photoconductor, specifically an inorganic photoconductor, more specifically an inorganic photoconductor including PbS, PbSe, Ge, InGaAs, extended InGaAs, InSb, Si, or HgCdTe.

[0083] Each photosensitive element may be sensitive to electromagnetic radiation in the wavelength range of 600 nm to 1000 μm, specifically in the wavelength range of 760 nm to 15 μm, more specifically in the wavelength range of 1 μm to 5 μm, and more specifically in the wavelength range of 1 μm to 3 μm.

[0084] Specifically, during calibration of the detector device, the detector device may be included by a spectrometer device, specifically by at least one of a reflection spectrometer device and a transmission spectrometer device.

[0085] In another aspect of the present invention, a computer program including instructions is disclosed. When the program is executed by a system according to the present invention (such as according to any one of the embodiments disclosed above and / or according to any one of the embodiments disclosed in further detail below), these instructions cause the evaluation unit of the system to execute a method for calibrating a spectrometer device in a batch of spectrometer devices according to the present invention (such as according to any one of the embodiments disclosed above and / or according to any one of the embodiments disclosed in further detail below).

[0086] Specifically, at least method steps a) and b) as indicated above may be executed by using the evaluation unit of the system that executes the computer program. Similarly, one, more than one, or even all of the method steps a3), aii), and ab) may be executed by using the evaluation unit of the system that executes the computer program. However, one, more than one, or even all of the method steps a1), a2), ai), and aa) as indicated above may be at least controlled and / or supported by the evaluation unit of the system that executes the computer program.

[0087] In another aspect of the present invention, a computer-readable storage medium including instructions, specifically a non-transitory computer-readable storage medium, is disclosed. When these instructions are executed by a system according to the present invention (such as according to any one of the embodiments disclosed above and / or according to any one of the embodiments disclosed in further detail below), these instructions cause the evaluation unit of the system to execute a method for calibrating a spectrometer device in a batch of spectrometer devices according to the present invention (such as according to any one of the embodiments disclosed above and / or according to any one of the embodiments disclosed in further detail below).

[0088] As used herein, the term "computer-readable storage medium" may specifically refer to a non-transitory data storage device, such as a hardware storage medium on which computer-executable instructions are stored. The computer-readable storage medium (also referred to as a computer-readable data carrier) may specifically be or may include storage media such as random access memory (RAM) and / or read-only memory (ROM).

[0089] The methods and systems according to the present invention can offer a number of advantages over known methods and devices. Specifically, the methods and systems according to the present invention can provide a global, use-case-independent calibration and correction scheme at the level of individual spectrometer devices, which enables the homogenization of the resulting spectral data sets to such an extent that accurate results can be produced by a trainable model across the entire spectrometer device population. Specifically, by using the methods and systems according to the present invention, spectral homogenization can be achieved for all spectrometer devices in a batch of spectrometer devices through system characterization and controlled degradation. The method and the system can use standardized, use-case-independent test procedures that are capable of characterizing the spectrometer devices, followed by digital post-processing that processes data from different spectrometer devices such that the same system characteristics can be simulated.

[0090] In summary, and without excluding additional possible embodiments, the following embodiments can be contemplated:

[0091] Embodiment 1: A method for calibrating a spectrometer device in a batch of spectrometer devices, wherein the spectrometer device includes at least one detector device, the at least one detector device includes at least one optical element configured to separate incident light into a spectrum having component wavelength components and further includes a plurality of photosensitive elements, wherein each photosensitive element is configured to receive at least a portion of one of the component wavelength components and to generate a corresponding detector signal based on the illumination of the corresponding photosensitive element by at least a portion of the corresponding component wavelength component, and wherein the method includes the following steps:

[0092] a) At least one system characterization step, the at least one system characterization step including determining a line spread function at corresponding wavelengths by comparing at least one spectrum measured by using the spectrometer device with at least one reference spectrum;

[0093] b) At least one resolution homogenization step, the at least one resolution homogenization step including converting the resolution of the line spread function for each wavelength to a predefined target resolution for the corresponding wavelength, wherein the target resolution for each wavelength is a predefined target batch resolution value for the corresponding wavelength.

[0094] Embodiment 2: The method according to the previous embodiment, wherein the predefined target batch resolution value A λ,target is selected such that the converted resolution A λ,conv for the corresponding wavelength of the spectrometer device λ,conv satisfies A λ,target .

[0095] Example 3: The method according to any one of the foregoing embodiments, wherein the corresponding resolution A of the line spread function λ,meas converting to a predefined target resolution includes convolving the measured spectrum with at least one kernel described by quadratic subtraction of the width.

[0096] Example 4: The method according to any one of the foregoing embodiments, wherein the line spread function is a Gaussian function having a measured full width at half maximum FWHM at wavelength λ λ and the predefined target batch resolution value is a predefined full width at half maximum FWHM λ,target wherein the conversion includes convolving the measured spectrum with a Gaussian kernel described by quadratic subtraction of the width.

[0097] Example 5: The method according to any one of the foregoing embodiments, wherein the line spread function describes the response distribution of the plurality of photosensitive elements to incident light having a specific wavelength.

[0098] Example 6: The method according to any one of the foregoing embodiments, wherein the system characterization step includes:

[0099] a1) irradiating the spectrometer device through at least one optical interferometer using at least one broadband light source;

[0100] a2) determining a plurality of detector signals for the plurality of photosensitive elements according to the irradiation through the optical interferometer in step a1); and

[0101] a3) determining the line spread function according to the plurality of detector signals.

[0102] Example 7: The method according to the previous embodiment, wherein the optical interferometer includes at least one interferometer selected from the group consisting of: a Michelson interferometer; a Fabry - Perot interferometer; a cube corner interferometer.

[0103] Example 8: The method according to any one of the foregoing two embodiments, wherein in step a1), the main frequency of the optical interferometer, specifically the main transmission frequency and / or main reflection frequency of the optical interferometer, varies within a pre - determined spectral range, and wherein in step a2), the plurality of detector signals are determined according to the main frequency of the optical interferometer.

[0104] Example 9: The method according to the previous example, wherein, in step a3), the line spread function is determined by comparing at least one of the main frequency of the optical interferometer, specifically the main transmission frequency and / or the main reflection frequency of the optical interferometer, with the pixel positions and identification numbers of the intensity peaks associated with the main frequency in the plurality of detector signals generated by the plurality of photosensitive elements.

[0105] Example 10: The method according to any one of the previous four examples, wherein the optical interferometer includes at least one beam splitting device for splitting the incident light into at least two illumination paths, wherein the optical interferometer further includes at least one scanning mirror on the first illumination path and at least one stationary mirror on the second illumination path, wherein, in the method, the scanning mirror moves along the first illumination path, and wherein the stationary mirror remains stationary.

[0106] Example 11: The method according to the previous example, wherein, in step a2), the plurality of detector signals are determined for a plurality of positions of the scanning mirror on the first illumination path, wherein the plurality of positions of the scanning mirror are different from each other, wherein step a3) includes associating the plurality of detector signals with the plurality of positions of the scanning mirror, and wherein, in step a3), associating the plurality of detector signals with the plurality of positions of the scanning mirror is for determining the line spread function.

[0107] Example 12: The method according to any one of the previous six examples, wherein step a3) includes processing the plurality of detector signals determined in step a2) to obtain a plurality of processed detector signals, wherein determining the line spread function in step a3) includes determining the line spread function based on the plurality of processed detector signals, wherein processing the plurality of detector signals includes transforming the plurality of detector signals, and wherein the plurality of detector signals are transformed by using at least one Fourier transform.

[0108] Example 13: The method according to any one of the previous examples, wherein the system characterization step includes:

[0109] ai) irradiating the spectrometer device with monochromatic light sources, the central wavelengths of which cover the wavelength range of the spectrometer device to be calibrated;

[0110] aii) determining the line spread function by comparing the known spectra of the monochromatic light sources with the spectra measured by using the spectrometer device.

[0111] Example 14: The method according to the previous example, wherein the monochromatic light sources comprise a continuous emitter combined with a band-pass filter, or a monochromatic emitter.

[0112] Example 15: The method according to any one of the previous two examples, wherein the intrinsic spectral width of the monochromatic light sources is comparable to the line spread function at the corresponding wavelength.

[0113] Example 16: The method according to any one of the previous three examples, wherein step aii) comprises broadening the known spectrum of the monochromatic light sources by performing kernel convolution using a theoretical line spread function, wherein step aii) comprises adjusting the parameters of the theoretical kernel until the broadened spectrum of the monochromatic light sources matches the measured spectrum, and wherein the adjusted kernel parameters are used to approximate the line spread function at the wavelength.

[0114] Example 17: The method according to the previous example, wherein the theoretical kernel is at least one kernel selected from the group consisting of: a Gaussian kernel having only one free parameter; a Lorentzian profile; a Moffat profile; or a Voigt profile; an asymmetric kernel.

[0115] Example 18: The method according to any one of the previous examples, wherein the system characterization step comprises:

[0116] aa) irradiating at least one reference object with at least one broadband light source;

[0117] ab) determining the line spread function by comparing the known spectrum of the reference object with the spectrum measured using the spectrometer device, wherein the known spectrum of the reference object is pre-determined by using at least one high-resolution spectrometer.

[0118] Example 19: The method according to the previous example, wherein step ab) comprises broadening the known spectrum of the reference object by performing kernel convolution using a theoretical line spread function, wherein step ab) comprises adjusting the parameters of the theoretical kernel until the broadened spectrum of the reference object matches the measured spectrum, and wherein the adjusted kernel parameters are used to approximate the line spread function at the wavelength.

[0119] Example 20: The method according to any one of the previous two examples, wherein step ab) comprises directly comparing the known spectrum of the reference object with the spectrum measured in the signal space using the spectrometer device and / or comparing at least one derivative of the known spectrum of the reference object with at least one derivative of the spectrum measured using the spectrometer device, specifically comparing the first-order derivative, second-order derivative, and / or higher-order derivatives of these spectra.

[0120] Example 21: A system for calibrating a spectrometer device in a batch of spectrometer devices, wherein the system includes a spectrometer device, the spectrometer device includes at least one detector device, wherein the detector device includes at least one optical element configured to separate incident light into a spectrum having component wavelength components and further includes a plurality of photosensitive elements, wherein each photosensitive element is configured to receive at least a portion of one of these component wavelength components and to generate a corresponding detector signal based on the illumination of the corresponding photosensitive element by at least a portion of the corresponding component wavelength component, wherein the system further includes at least one evaluation unit, wherein the evaluation unit is configured to perform the method for calibrating a spectrometer device in a batch of spectrometer devices according to any one of the preceding embodiments.

[0121] Example 22: The system according to the previous embodiment, wherein the evaluation unit includes at least one data storage unit configured to store at least one of the reference spectrum and the target resolution.

[0122] Example 23: The system according to any one of the preceding embodiments related to the system, wherein the evaluation unit includes at least one retrieval interface configured to retrieve at least one of the reference spectrum and the target resolution, specifically for retrieving at least one of the reference spectrum and the target resolution from a cloud computer network.

[0123] Example 24: The system according to any one of the preceding embodiments related to the system, wherein the system further includes at least one broadband light source and at least one optical interferometer, both of which are arranged to irradiate the spectrometer device through the optical interferometer using the broadband light source.

[0124] Example 25: The system according to any one of the preceding embodiments related to the system, wherein the system further includes at least one reference object and at least one broadband light source.

[0125] Example 26: The system according to any one of the preceding two embodiments, wherein the broadband light source includes at least one of the following: incandescent lamp; blackbody radiator; electric lamp filament; light-emitting diode.

[0126] Example 27: The system according to any one of the preceding embodiments related to the system, wherein the system further includes monochromatic light sources, the central wavelengths of which cover the wavelength range of the spectrometer device to be calibrated.

[0127] Example 28: The system according to any one of the foregoing embodiments of the system, wherein the optical element includes at least one wavelength-selective element, and wherein the wavelength-selective element includes at least one element selected from the group consisting of: a prism; a grating; a linear gradient filter; an optical filter.

[0128] Example 29: The system according to any one of the foregoing embodiments of the system, wherein the detector device includes a plurality of photosensitive elements arranged in a linear array, and wherein the photosensitive elements of the linear array include from 10 to 1000 photosensitive elements, specifically from 100 to 500 photosensitive elements, specifically from 200 to 300 photosensitive elements, more specifically 256 photosensitive elements, and most specifically 128 photosensitive elements.

[0129] Example 30: The system according to any one of the foregoing embodiments of the system, wherein each photosensitive element includes at least one element selected from the group consisting of: a pixelated inorganic camera element, specifically a pixelated inorganic camera chip, more specifically a CCD chip or a CMOS chip; a monochromatic camera element, specifically a monochromatic camera chip; at least one photoconductor, specifically an inorganic photoconductor, more specifically an inorganic photoconductor including PbS, PbSe, Ge, InGaAs, extended InGaAs, InSb, Si, or HgCdTe.

[0130] Example 31: The system according to any one of the foregoing embodiments of the system, wherein each photosensitive element is sensitive to electromagnetic radiation in the wavelength range from 600 nm to 1000 μm, specifically in the wavelength range from 760 nm to 15 μm, more specifically in the wavelength range from 1 μm to 5 μm, and more specifically in the wavelength range from 1 μm to 3 μm.

[0131] Example 32: The system according to any one of the foregoing embodiments of the system, wherein the detector device is included by the spectrometer device, specifically by at least one of a reflection spectrometer device and a transmission spectrometer device.

[0132] Example 33: A computer program including instructions that, when executed by the system according to any one of the foregoing embodiments of the system, cause the evaluation unit of the system to perform the method for calibrating a spectrometer device in a batch of spectrometer devices according to any one of the foregoing embodiments of the method.

[0133] Embodiment 34: A computer-readable storage medium, specifically a non-transitory computer-readable storage medium, comprising instructions which, when executed by a system according to any one of the preceding embodiments relating to the system, cause the evaluation unit of the system to perform a method for calibrating a spectrometer device in a batch spectrometer device according to any one of the preceding embodiments relating to the method. Description of the Drawings

[0134] Additional optional features and embodiments will be disclosed in more detail in subsequent embodiments preferably in combination with the dependent claims. Wherein, as will be recognized by the person skilled in the art, the corresponding 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 drawings. Wherein, the same reference numerals in these drawings denote identical or functionally equivalent elements.

[0135] In the drawings:

[0136] Figures 1A to 1C An embodiment of a system for calibrating a spectrometer device in a batch spectrometer device is schematically shown;

[0137] Figures 2A to 2C An embodiment of a method for calibrating a spectrometer device in a batch spectrometer device is shown;

[0138] Figure 3 An exemplary spectrum measured by using a spectrometer device is shown;

[0139] Figure 4 An exemplary line spread function is shown; and

[0140] Figure 5 An exemplary spectrum measured by using two different spectrometer devices is shown. Detailed Description of the Invention

[0141] Figures 1A to 1C An exemplary embodiment of a system 110 for calibrating a spectrometer device 112 in a batch spectrometer device 112 is schematically shown. Figures 1A to 1C The embodiments of can widely correspond to each other. Below, Figures 1A to 1C They will be described in combination.

[0142] System 110 includes a spectrometer device 112 and at least one detector device 114. The detector device 114 includes at least one optical element 116 configured to separate incident light 118 into a spectrum having constituent wavelength components 120. The optical element 116 may specifically include at least one wavelength selection element 122. For example, the wavelength selection element 122 may include at least one element selected from the group consisting of: a prism; a grating; a linear variable filter; an optical filter.

[0143] Further, the detector device 114 includes a plurality of photosensitive elements 124, wherein each photosensitive element 124 is configured to receive at least a portion of one of the constituent wavelength components 120 and to generate a corresponding detector signal based on the illumination of the corresponding photosensitive element 124 by at least a portion of the corresponding constituent wavelength component 120. As Figures 1A to 1C shown, the detector device 114 may include a plurality of photosensitive elements 124 arranged in a linear array 126. In Figures 1A to 1C an exemplary embodiment, the linear array 126 of photosensitive elements 124 may include 128 photosensitive elements 124. Each photosensitive element 124 may include at least one element selected from the group consisting of: a pixelated inorganic camera element, specifically a pixelated inorganic camera chip, more specifically a CCD chip or a CMOS chip; a monochromatic camera element, specifically a monochromatic camera chip; at least one photoconductor, specifically an inorganic photoconductor, more specifically an inorganic photoconductor including PbS, PbSe, Ge, InGaAs, extended InGaAs, InSb, Si, or HgCdTe. Each photosensitive element 124 may be sensitive to electromagnetic radiation in the wavelength range of 600 nm to 1000 μm, specifically in the wavelength range of 760 nm to 15 μm, more specifically in the wavelength range of 1 μm to 5 μm, more specifically in the wavelength range of 1 μm to 3 μm.

[0144] In Figure 1A an embodiment, the system 110 may further include at least one broadband light source 128 and at least one optical interferometer 130, which are arranged to illuminate the spectrometer device 112 with the broadband light source 128 through the optical interferometer 130. The broadband light source 128 may include, for example, at least one of the following: an incandescent lamp; a blackbody radiator; an electric filament; a light-emitting diode. The optical interferometer 130 may include at least one interferometer selected from the group consisting of: a Michelson interferometer; a Fabry - Perot interferometer; a cube corner interferometer. For further details regarding the optical interferometer 130, reference is made to the above description.

[0145] In Figure 1BIn an embodiment, system 110 may further include at least one broadband light source 128. However, in this embodiment, system 110 may further include at least one reference object 132. The reference object 132 may specifically be an object having known spectral characteristics (such as known reflection and / or transmission characteristics).

[0146] In Figure 1C an embodiment, system 110 may further include monochromatic light sources 134, the central wavelengths of these monochromatic light sources covering the wavelength range of the spectrometer device 112 to be calibrated. System 110 may specifically include a plurality of monochromatic light sources 134. The monochromatic light sources 134 may include a continuous emitter 136 (such as the broadband light source 128) combined with a bandpass filter 138, or a monochromatic emitter 140 (such as a laser, etc.). In the case of the monochromatic emitter 140, system 110 may not include any additional elements between the emitter 140 and the spectrometer device 112. The intrinsic spectral width of the monochromatic light sources 134 may be comparable to the line spread function of the spectrometer device 112 at the corresponding wavelengths.

[0147] As Figures 1A to 1C shown, system 110 further includes at least one evaluation unit 142. The evaluation unit 142 is configured to perform a method for calibrating the spectrometer device 112 in a batch of spectrometer devices 112 according to the present invention (such as according to any one of the embodiments described with respect to Figures 2A to 2C ). For the description of this method, reference is made to Figures 2A to 2C . However, in any other embodiment disclosed herein, the evaluation unit 142 may also be configured to perform a method for calibrating the spectrometer device 112 in a batch of spectrometer devices 112 according to the present invention. As indicated by the arrow 144 in Figures 1A to 1C , the spectrometer device 112, specifically the detector device 114, may be configured to communicate with the evaluation unit 142, specifically for transmitting a detector signal to the evaluation unit 142.

[0148] Figures 2A to 2C shows an exemplary embodiment of a method for calibrating the spectrometer device 112 in a batch of spectrometer devices 112. For possible embodiments of the spectrometer device 112, reference is made to Figures 1A to 1C and the corresponding description. Figures 2A to 2C The embodiments of the method shown correspond widely to each other. Below, Figures 2A to 2C they will be described in combination.

[0149] The method includes the following steps:

[0150] a) At least one system characterization step (represented by reference numeral 146), the at least one system characterization step including determining a line spread function at corresponding wavelengths by comparing at least one spectrum measured by using a spectrometer device 112 with at least one reference spectrum;

[0151] b) At least one resolution homogenization step (represented by reference numeral 148), the at least one resolution homogenization step including converting the resolution of the line spread function to a predefined target resolution for the corresponding wavelength for each wavelength, wherein the target resolution for each wavelength is a predefined target batch resolution value for the corresponding wavelength.

[0152] As an example, these steps may be performed in a given order. However, it should be noted that different orders are also possible. Further, one or more method steps may be performed once or repeatedly. Further, two or more method steps may be performed simultaneously or in a timely overlapping manner. The method may include additional method steps not listed.

[0153] For Figure 2A an exemplary embodiment of the method shown, the system 110 as shown in Figure 1A the embodiment may be used. In this example, the system characterization step 146 may include:

[0154] a1) (represented by reference numeral 150) irradiating the spectrometer device 112 through at least one optical interferometer 130 by using at least one broadband light source 128;

[0155] a2) (represented by reference numeral 152) determining a plurality of detector signals for a plurality of photosensitive elements 124 according to the irradiation through the optical interferometer 130 in step a1); and

[0156] a3) (represented by reference numeral 154) determining the line spread function according to the plurality of detector signals.

[0157] In step a1), the main frequency of the optical interferometer 130, specifically the main transmission frequency and / or the main reflection frequency of the optical interferometer 130, may vary within a pre-determined spectral range. In step a2), the plurality of detector signals may be determined according to the main frequency of the optical interferometer 130. In step a3), the line spread function may be determined by comparing the main frequency of the optical interferometer 130, specifically the main transmission frequency and / or the main reflection frequency of the optical interferometer 130, with at least one of the pixel positions and identification numbers of the intensity peaks associated with the main frequency in the plurality of detector signals generated by the plurality of photosensitive elements 124.

[0158] As an example, the optical interferometer 130 may include at least one beam splitting device for splitting the incident light into at least two illumination paths. The optical interferometer 130 may further include at least one scanning mirror on the first illumination path and at least one stationary mirror on the second illumination path ( Figure 1A not shown in

[0159] ). In this method, specifically in steps a1) and a2), the scanning mirror may be moved along the first illumination path, wherein the stationary mirror may remain stationary. Specifically, in step a2), a plurality of detector signals may be determined for a plurality of positions of the scanning mirror on the first illumination path. The plurality of positions of the scanning mirror may be different from each other. Step a3) may further include correlating the plurality of detector signals with the plurality of positions of the scanning mirror. Specifically, in step a3), correlating the plurality of detector signals with the plurality of positions of the scanning mirror may be used to determine the line spread function.

[0160] For Figure 2B an exemplary embodiment of the method shown, the system 110 as shown in Figure 1B the embodiment may be used. In this example, the system characterization step 146 may include:

[0161] aa) (represented by reference numeral 156) irradiating at least one reference object 132 by using at least one broadband light source 128;

[0162] ab) (represented by reference numeral 158) determining the line spread function by comparing the known spectrum of the reference object 132 with the spectrum measured by using the spectrometer device 112, wherein the known spectrum of the reference object 132 is pre-determined by using at least one high-resolution spectrometer.

[0163] Step ab) may include broadening the known spectrum of the reference object 132 by performing kernel convolution with a theoretical line spread function. Step ab) may include adjusting the parameters of the theoretical kernel until the broadened spectrum of the reference object 132 matches the measured spectrum. The adjusted kernel parameters may be used to approximate the line spread function at that wavelength. The theoretical kernel may be at least one kernel selected from the group consisting of: a Gaussian kernel having only one free parameter; a Lorentz profile; a Moffat profile; or a Voigt profile; an asymmetric kernel.

[0164] Step ab) may include directly comparing the known spectrum of the reference object 132 with the spectrum measured in the signal space by using the spectrometer device 112 and / or comparing at least one derivative of the known spectrum of the reference object 132 with at least one derivative of the spectrum measured by using the spectrometer device 112, specifically comparing the first-order derivative, second-order derivative and / or higher-order derivatives of these spectra.

[0165] Figure 3 Exemplary results of steps aa) and ab) are shown. Specifically, Figure 3 A graph of reflectance 160 as a function of wavelength 162 is shown, where the measurement unit of wavelength 162 is nm. Figure 3 An exemplary known spectrum 164 of the reference object 132 (a rare-earth wavelength standard in this example) is shown, and the known spectrum 164 is measured with a high-resolution spectrometer (an MPA spectrometer in this example). Figure 3 Further shown is the spectrum of the reference object 132 measured by using the spectrometer device 112 (denoted by reference numeral 166), and the known spectrum of the reference object 132 broadened by Gaussian kernel convolution when the FWHM is 5 nm (denoted by reference numeral 166), when the FWHM is 10 nm (denoted by reference numeral 168), and when the FWHM is 15 nm (denoted by reference numeral 166). As Figure 4 can be seen, the best results are obtained by broadening with an FWHM of 15 nm. The line spread function in this wavelength region can be approximated by a Gaussian kernel with an FWHM of 15 nm.

[0166] For Figure 2C an exemplary embodiment of the method shown, the system 110 shown in the embodiment such as Figure 1C can be used. In this example, the system characterization step 146 may include:

[0167] ai) (denoted by reference numeral 174) irradiating the spectrometer device 112 by using monochromatic light sources 134, and the central wavelengths of these monochromatic light sources cover the wavelength range of the spectrometer device 112 to be calibrated;

[0168] aii) (denoted by reference numeral 176) determining the line spread function by comparing the known spectra of these monochromatic light sources 134 with the spectra measured by using the spectrometer device 112.

[0169] Step aii) may include broadening the known spectrum of the monochromatic light source 134 by performing kernel convolution using a theoretical line spread function. Step aii) may specifically include adjusting the parameters of the theoretical kernel until the broadened spectrum of the monochromatic light source 134 matches the measured spectrum. The adjusted kernel parameters may be used to approximate the line spread function at that wavelength. The theoretical kernel may be at least one kernel selected from the group consisting of: a Gaussian kernel having only one free parameter; a Lorentzian profile; a Moffat profile; or a Voigt profile; an asymmetric kernel. Other kernels may also be feasible. However, for example, the theoretical kernel may be a Gaussian kernel having only one free parameter. In this example, the free parameter of the Gaussian kernel may be the full width at half maximum (FWHM).

[0170] Figure 4 Exemplary results of steps ai) and aii) are shown. Specifically, Figure 4 a plot of the relative signal intensity 178 as a function of the wavelength 180, where the wavelength 180 is measured in nm, is shown. In Figure 4 it, the known spectrum 182 of the monochromatic light source 134 (here a monochromatic light source at 1500 nm), the spectrum 184 of the monochromatic light source 134 measured by using the spectrometer device 112, and a plurality of broadened spectra 186, 188, 190 are shown. Figure 4 The broadened spectra 186, 188, 190 of Figure 4 can be obtained by broadening the known spectrum 182 of the monochromatic light source 134 by using Gaussian kernel convolution, specifically with Gaussian kernel convolution at FWHM of 2.5 nm (represented by reference numeral 186), FWHM of 5 nm (represented by reference numeral 188), FWHM of 7.5 nm (represented by reference numeral 190), and FWHM of 10 nm (represented by reference numeral 192). As

[0171] Returning to Figures 2A to 2C , in the resolution homogenization step, the predefined target batch resolution value A λ,target can be selected such that the converted resolution A λ,conv for the corresponding wavelength of the spectrometer device 112 satisfies A λ,conv ≤A λ,target . Specifically, converting the corresponding resolution A λ,meas of the line spread function to the predefined target resolution may include convolving the measured spectrum with at least one kernel whose width is described by quadratic subtraction .

[0172] Figure 5Shows exemplary spectra measured by using two different spectrometer devices 112. The two different spectrometer devices 112 can be spectrometer devices 112 from the same batch of spectrometer devices 112 and can thus be implemented similarly relative to each other. The spectrometer device 112 can be specifically implemented as shown in any one of FIGS. 1 to Figure 3 as shown. Thus, for a detailed description of the spectrometer device 112 for measuring the Figure 5 spectra shown, reference is made to the description of FIGS. 1 to Figure 3 . Figure 5 Specifically shows a graph of the measured absorbance 194 of a sample as a function of wavelength 196. In this example, the sample being measured is a polyethylene terephthalate (PET) sample measured by diffuse reflection. Figure 5 shows a portion of the spectrum measured by using the spectrometer device 112, specifically the spectral region around the triplet of PET near 2150 nm. In Figure 5 , the spectrum measured by the first spectrometer device 112 is denoted by reference numeral 198, and the spectrum measured by the second spectrometer device 112 is denoted by reference numeral 200. Although the two spectrometer devices 112 can be spectrometer devices from the same batch of spectrometer devices, the first spectrometer device 112 can show a higher resolution compared to the second spectrometer device 122. In Figure 5 , it can be seen that the peak of the spectrum 198 of the first spectrometer device 112 is higher than the peak of the spectrum 200 of the second spectrometer device 112, thus showing a higher resolution. Figure 5 The differences in the measured spectra are highlighted by circles in Figure 5 . The original spectrum is indicated by reference numeral 202 in Figure 5 . Figure 5 Also shown in the same figure are the spectra of the two spectrometer devices 112 after performing the resolution homogenization step. The spectra after performing the resolution homogenization step are denoted by reference numeral 204 and are shifted in the figure for better visibility. In the processed spectrum 204 after the resolution homogenization step, the two spectrometer devices 112 can show the same nominal resolution and thus show more similar features.

[0173] List of Reference Numerals

[0174] 110 System

[0175] 112 Spectrometer Device

[0176] 114 Detector Device

[0177] 116 Optical Element

[0178] 118 Incident Light

[0179] 120 Component wavelength components

[0180] 122 Wavelength selection element

[0181] 124 Photosensitive element

[0182] 126 Linear array

[0183] 128 Broadband light source

[0184] 130 Optical interferometer

[0185] 132 Reference object

[0186] 134 Monochromatic light source

[0187] 136 Continuous emitter

[0188] 138 Bandpass filter

[0189] 140 Monochromatic emitter

[0190] 142 Evaluation unit

[0191] 144 Arrow

[0192] 146 System characterization step

[0193] 148 Resolution homogenization step

[0194] 150 Irradiation spectrometer device

[0195] 152 Determine detector signal

[0196] 154 Determine line spread function

[0197] 156 Irradiate reference object

[0198] 158 Determine line spread function

[0199] 160 Reflectivity

[0200] 162 Wavelength

[0201] 164 Known spectrum

[0202] 166 Spectrum of the reference object measured using a spectrometer device

[0203] 168 Broadened known spectrum of the reference object with a FWHM of 5 nm

[0204] 170 Broadened known spectrum of the reference object with a FWHM of 10 nm

[0205] 172 Broadened known spectrum of the reference object with a FWHM of 15 nm

[0206] 174 By irradiating a spectrometer device with a monochromatic light source

[0207] 176 Determining the line spread function

[0208] 178 Relative signal intensity

[0209] 180 Wavelength

[0210] 182 Known spectrum of the monochromatic light source

[0211] 184 Spectrum of the monochromatic light source measured by using the spectrometer device

[0212] 186 Broadened known spectrum of the monochromatic light source with an FWHM of 2.5 nm

[0213] 188 Broadened known spectrum of the monochromatic light source with an FWHM of 5 nm

[0214] 190 Broadened known spectrum of the monochromatic light source with an FWHM of 7.5 nm

[0215] 192 Broadened known spectrum of the monochromatic light source with an FWHM of 10 nm

[0216] 194 Absorbance

[0217] 196 Wavelength

[0218] 198 Spectrum of the first spectrometer device

[0219] 200 Spectrum of the second spectrometer device

[0220] 202 Original spectrum

[0221] 204 Processed spectrum

Claims

1. A method for calibrating a spectrometer device (112) in a batch of spectrometer devices (112), wherein, The spectrometer device (112) includes at least one detector device (114), the at least one detector device including at least one optical element (116) configured to separate incident light (118) into a spectrum having component wavelength components (120) and further including a plurality of photosensitive elements (124), wherein each photosensitive element (124) is configured to receive at least a portion of one of the component wavelength components (120) and to generate a corresponding detector signal based on the illumination of the corresponding photosensitive element (124) by at least a portion of the corresponding component wavelength component (120), wherein the method includes the following steps: a) At least one system characterization step, the at least one system characterization step including determining a line spread function at corresponding wavelengths by comparing at least one spectrum measured by using the spectrometer device (112) with at least one reference spectrum; b) At least one resolution homogenization step, the at least one resolution homogenization step including converting the resolution of the line spread function to a predefined target resolution for the corresponding wavelength for each wavelength, wherein the target resolution for each wavelength is a predefined target batch resolution value for the corresponding wavelength.

2. The method according to the preceding claim, wherein The predefined target batch resolution value Aλ,target is selected such that the converted resolution Aλ,conv for the corresponding wavelength of the spectrometer device (112) satisfies Aλ,conv ≤ Aλ,target.

3. The method according to any one of the preceding claims, wherein, Converting the corresponding resolution Aλ,meas of the line spread function to a predefined target resolution includes convolving the measured spectrum with at least one kernel described by a quadratic subtraction described by a quadratic subtraction 4. The method according to any one of the preceding claims, wherein, The system characterization step includes: a1) Illuminating the spectrometer device (112) through at least one optical interferometer (130) by using at least one broadband light source (128); a2) For the plurality of photosensitive elements (124), determining a plurality of detector signals based on the illumination through the optical interferometer (130) in step a1); and a3) Determining the line spread function based on the plurality of detector signals.

5. The method according to the preceding claim, wherein, In step a1), the main frequency of the optical interferometer (130) varies within a predefined spectral range, and wherein, in step a2), the plurality of detector signals are determined based on the main frequency of the optical interferometer (130), wherein, in step a3), the line spread function is determined by comparing the main frequency of the optical interferometer (130) with at least one of the pixel positions and identification numbers of the plurality of photosensitive elements (124) that generate intensity peaks associated with the main frequency among the plurality of detector signals.

6. The method according to any one of the preceding two claims, wherein, The optical interferometer (130) includes at least one beam splitting device for splitting the incident light into at least two illumination paths, wherein the optical interferometer (130) further includes at least one scanning mirror on the first illumination path and at least one stationary mirror on the second illumination path, wherein, in the method, the scanning mirror moves along the first illumination path, wherein the stationary mirror remains stationary, wherein, in step a2), the plurality of detector signals are determined for a plurality of positions of the scanning mirror on the first illumination path, wherein the plurality of positions of the scanning mirror are different from each other, wherein step a3) includes correlating the plurality of detector signals with the plurality of positions of the scanning mirror, wherein, in step a3), correlating the plurality of detector signals with the plurality of positions of the scanning mirror is for determining the line spread function.

7. The method according to any one of the preceding three claims, wherein, Step a3) includes processing the plurality of detector signals determined in step a2) to obtain a plurality of processed detector signals, wherein determining the line spread function in step a3) includes determining the line spread function based on the plurality of processed detector signals, wherein processing the plurality of detector signals includes transforming the plurality of detector signals, wherein the plurality of detector signals are transformed by using at least one Fourier transform.

8. The method according to any one of the preceding claims, wherein, The system characterization step includes: ai) irradiating the spectrometer device (112) by using a monochromatic light source (134), the central wavelengths of these monochromatic light sources covering the wavelength range of the spectrometer device (112) to be calibrated; aii) determining the line spread function by comparing the known spectra of these monochromatic light sources (134) with the spectra measured by using the spectrometer device (112).

9. The method according to the preceding claim, wherein, Step aii) includes broadening the known spectra of these monochromatic light sources (134) by using kernel convolution with a theoretical line spread function, wherein step aii) includes adjusting the parameters of the theoretical kernel until the broadened spectra of these monochromatic light sources (134) match the measured spectra, wherein the adjusted kernel parameters are used to approximate the line spread function at this wavelength.

10. The method according to any one of the preceding claims, wherein, The system characterization step includes: aa) irradiating at least one reference object (132) by using at least one broadband light source (128); ab) determining the line spread function by comparing the known spectrum of the reference object (132) with the spectrum measured by using the spectrometer device (112), wherein the known spectrum of the reference object (132) is pre-determined by using at least one high-resolution spectrometer.

11. The method according to the preceding claim, wherein, Step ab) includes broadening the known spectrum of the reference object (132) by using kernel convolution with a theoretical line spread function, wherein step ab) includes adjusting the parameters of the theoretical kernel until the broadened spectrum of the reference object (132) matches the measured spectrum, wherein the adjusted kernel parameters are used to approximate the line spread function at this wavelength.

12. The method according to any one of the preceding two claims, wherein, Step ab) comprises directly comparing the known spectrum of the reference object (132) with the spectrum measured in the signal space by means of the spectrometer device (112) and / or comparing at least one derivative of the known spectrum of the reference object (132) with at least one derivative of the spectrum measured by means of the spectrometer device (112), specifically comparing the first, second and / or higher order derivatives of these spectra.

13. A system (110) for calibrating a spectrometer device (112) in a batch of spectrometer devices (112), wherein, The system (110) comprises the spectrometer device (112), which comprises at least one detector device (114), wherein the detector device (114) comprises at least one optical element (116) configured to separate the incident light (118) into a spectrum having component wavelength components (120) and further comprises a plurality of photosensitive elements (124), wherein each photosensitive element (124) is configured to receive at least a portion of one of the component wavelength components (120) and to generate a corresponding detector signal based on the illumination of the corresponding photosensitive element (124) by at least a portion of the corresponding component wavelength component (120), wherein the system (110) further comprises at least one evaluation unit (142), wherein the evaluation unit (142) is configured to perform the method for calibrating the spectrometer device (112) in a batch of spectrometer devices (112) according to any one of the preceding claims.

14. A computer program comprising instructions which, when executed by a system (110) according to any one of the preceding claims relating to the system (110), cause the evaluation unit (142) of the system (110) to perform the method for calibrating the spectrometer device (112) in a batch of spectrometer devices (112) according to any one of the preceding claims relating to the method.

15. A computer-readable storage medium, specifically a non-transitory computer-readable storage medium, comprising instructions which, when executed by a system (110) according to any one of the preceding claims relating to the system (110), cause the evaluation unit (142) of the system (110) to perform the method for calibrating the spectrometer device (112) in a batch of spectrometer devices (112) according to any one of the preceding claims relating to the method.

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