Portable spectrometer

Abstract

This invention is in the field of portable spectrometer devices. a. An interface to an application, configured to receive a request to perform a spectroscopic measurement and to provide the spectroscopic measurement results to the application. b. A spectrometer module configured to receive electromagnetic radiation and generate spectral data including intensity values, wherein each intensity value indicates the intensity of electromagnetic radiation in at least a portion of its spectral range, and c. A processor configured to trigger a spectrometer module to perform a spectroscopic measurement in response to a request received via an interface, and to receive spectroscopic data from the spectrometer module, wherein the processor is further configured to derive compositional data from the spectroscopic data and to provide the spectroscopic data and compositional data to the interface. This relates to a spectrometer equipped with the following features.

Description

[Technical Field]

[0001] The present invention is in the field of portable spectrometer devices, for example, spectrometers integrated in smartphones. The present invention relates to a spectrometer, a portable device comprising a spectrometer, a method for performing spectroscopic analysis, a non-transitory computer-readable medium, and a method of using spectral data and composition data obtained by a spectrometer to provide recommendations for acting on a composition of an object or the object based on its composition. [Background Art]

[0002] Spectrometer modules that can be integrated into portable devices such as smartphones or tablets will soon be commercially available. These can provide users with useful information that is not visible to the naked eye, such as the chemical composition of an object.

[0003] CN114062304A discloses a smartphone having an integrated spectrometer. However, it remains unclear how the accuracy of a spectrometer can be guaranteed under changing environmental conditions such as temperature changes or aging degradation of sensors. Spectrometers need to be calibrated to compensate for such effects. However, in smartphones, doing this manually is very inconvenient for users.

[0004] WO2018 / 090142A1 discloses a spectrophotometric analysis method for low-resolution spectrophotometric sensors. A mathematical model that compensates for imperfections of LRSS compared to high-resolution spectrometers. However, maintaining the accuracy of the sensor under changing environmental conditions is not addressed by D1. [Prior Art Documents] [Patent Documents]

[0005] [Patent Document 1] CN114062304A [Patent Document 2] WO2018 / 090142A1 [Overview of the project] [Problems that the invention aims to solve]

[0006] The objective of the present invention was to provide a spectrometer that provides reliable spectral information under changing environmental conditions without imposing a calibration task on the user. [Means for solving the problem]

[0007] In one embodiment, the present invention is a. An interface to an application, configured to receive requests for performing spectroscopic measurements and to provide measurement data to the application. b. A spectrometer module configured to receive electromagnetic radiation and generate measurement data based on electromagnetic radiation, and c. A processor configured to determine whether calibration is required, and if so, to trigger the spectrometer module to perform calibration. This relates to a spectrometer equipped with the following features.

[0008] In another embodiment, the present invention relates to a portable device encompassing a spectrometer according to the present invention.

[0009] In another embodiment, the present invention is: a. Receiving requests to perform spectroscopic measurements via an interface to the application. b. Upon request, determine whether calibration is required, and if so, trigger the spectrometer module to perform the calibration. c. Trigger the spectrometer module to perform a spectroscopic measurement. d. Receiving measurement data from the spectrometer module, and e. Providing measurement data to the application via the interface. This relates to a method for performing spectroscopic analysis, including [specific details omitted].

[0010] In another embodiment, the present invention relates to a non-temporary computer-readable medium that, when executed by one or more processors, includes instructions causing one or more processors to determine whether calibration is required, and, if the determination results in calibration being required, to trigger a spectrometer module to perform calibration.

[0011] In another embodiment, the present invention relates to a method for using measurement data obtained by a spectrometer or method according to any one of the prior claims to provide the composition of an object or a recommendation for acting on an object based on its composition.

[0012] Reliable spectrometer measurement results are achieved by determining whether calibration is required and triggering the spectrometer module to perform calibration only when the determination indicates that calibration is necessary. At the same time, hardware resources, such as battery energy, are conserved because unnecessary calibrations are avoided. The present invention further enables a calibration scheme that is adjusted according to the use case. Calibration can be performed more frequently for use cases that require high accuracy, while hardware resources can be conserved for use cases that require lower accuracy. Additionally, measurements can be accelerated, for example, in cases where a series of measurements are performed and, due to certain conditions, calibration may not be required between each measurement. Thus, calibration is performed only a minimum number of times, i.e., only when the determination indicates that calibration is necessary. Generally, there are no manual actions required by the user to speed up the process.

[0013] The term "application" may refer to a portion of executable program code that performs one or more specific tasks unrelated to the operation of the device. An application may include a user interface, such as a graphical user interface (GUI), to receive input from the user and display information to the user. An application typically utilizes hardware through a programming interface, such as a programming interface to an operating system. Applications may be pre-installed on the device by the device manufacturer or provided by other software providers, for example, in an app store, so that users can download and install applications. In the context of this invention, an application may utilize a spectrometer; that is, an application may process information obtained from a spectrometer.

[0014] The application may be configured to make fitness and health information available to the user, for example, by triggering a spectrometer to measure the user's skin and making the skin's moisture level or skin's blood glucose or lactose content available to the user. Alternatively or additionally, the application may make recommendations available to the user, for example, to drink water according to their skin's moisture level or to adjust their training program according to their blood lactose level.

[0015] The application may be configured to make information about agricultural products, food, or feed available to the user. The application may trigger a spectrometer to measure agricultural products; e.g., fruits, vegetables, meat, dairy products; food, e.g., bread, sauces, sausages, confectionery; feed, e.g., fodder or hay. Once measurement results are obtained from the spectrometer, the application may make relevant content, e.g., sugar or protein content, available to the user. Alternatively or additionally, the application may make recommendations available to the user, e.g., expected harvest dates for farmers or appropriate recipes for cooks.

[0016] The application may be configured to generate recycling-related information for the user. The application may trigger a spectrometer to measure objects to be recycled, such as plastic objects like bottles or metal objects like cans. Once the measurement results are obtained from the spectrometer, the application may make available to the user the relevant material from which the object is made, for example, polyethylene terephthalate (PET) for bottles. Alternatively or additionally, the application may make available to the user recommendations, such as the most appropriate way to recycle the object or the most convenient place to store the object so that it can be recycled.

[0017] The term "interface" can refer to a shared boundary through which a spectrometer can exchange information with an application, for example, through its firmware or the operating system of the device in which the spectrometer is incorporated. An interface may be, or include, an application programming interface (API) configured to receive function calls, messages, or other types of invocations that, when executed, enable information exchange between the application and the spectrometer. Additionally, an API may provide the calling program code of an application with the ability to use types or classes of data defined in the API and implemented in the called program code. An interface may include further functionality, such as hardware-specific tools that can communicate with the spectrometer hardware and / or portable devices. Thus, an interface may be, or include, part of a software development kit (SDK).

[0018] The interface may be configured to receive a request for performing spectrometry. The interface may receive a measurement request for performing spectrometry from an application. The interface may be configured to receive measurement requests from two or more applications. The interface may be configured to receive two or more measurement requests simultaneously. Such a measurement request may be a function call provided by the interface. Alternatively, the measurement request may be an entry, for example a queued file, to a request list that is provided by the interface and is continuously read by the interface in order to respond to the measurement request. The measurement request may further include parameters for influencing the measurement, for example the sample time of the measurement or the number of times the measurement is repeated.

[0019] The interface may be configured to receive a request for performing calibration. The interface may receive a request for performing calibration from an application. The interface may be configured to receive calibration requests from two or more applications. The interface may be configured to receive two or more calibration requests simultaneously. Such a calibration request may be a function call provided by the interface. Alternatively, the calibration request may be an entry, for example a queued file, to a calibration request list that is provided by the interface and is continuously read by the interface in order to respond to the calibration request. The calibration request may further include parameters for influencing the calibration, for example the type of calibration or the sample time of the calibration.

[0020] A measurement or calibration request may be transferred to a spectrometer module to trigger the measurement or calibration. The measurement or calibration request may be transferred directly from the interface to the firmware of the spectrometer module. The measurement or calibration request may be transferred from the interface to an operating system, which may transfer the measurement or calibration request to the firmware of the spectrometer module.

[0021] An operating system may include a hardware abstraction layer (HAL) and a kernel. The HAL may be executed in the user space of a processor, that is, using limited memory access, for example user space in virtual memory, and the kernel may be executed in the kernel mode of the processor, that is, without limited memory access, for example in kernel space in virtual memory.

[0022] Accordingly, a measurement or calibration request may be transferred from an interface to the HAL of the operating system, the HAL may transfer it to the kernel of the operating system, and the kernel may transfer it to the firmware of the spectrometer module. Each instance may modify the measurement or calibration request in a manner that makes it compatible with the next instance.

[0023] The HAL can receive standardized, that is, hardware-independent function calls or messages and convert them into hardware-specific ones. The HAL may be a pass-through HAL or a binderized HAL. The HAL may include a spectroscopy HAL dedicated to providing a software interface to the spectroscopy hardware, such as an interface to a spectroscopy hardware driver.

[0024] The spectroscopy HAL may provide spectroscopy hardware-specific functions and hardware access. One example is invoking a calibration function of a spectroscopy module.

[0025] The kernel of the operating system may include a driver for the spectrometer module. The kernel may receive a measurement or calibration request from the HAL, generate hardware-specific code to trigger the spectroscopy module to perform the measurement or calibration. The kernel may transfer the request to the firmware of the spectroscopy module.

[0026] The firmware controls the actual functionality of the spectroscopic hardware, such as the conversion of sensor signals from analog to digital.

[0027] The firmware may further provide metadata and / or calibration coefficients. The metadata may relate to sensor data, such as temperature measured in or near the spectroscopic module, or motion data measured during spectroscopic measurements, such as by a gyroscope.

[0028] Calibration coefficients may relate to usable values ​​for correcting the output of the spectrometer module to compensate for manufacturing defects or drift due to aging. Calibration coefficients may arise from tests immediately after the spectrometer module is manufactured, such as end-of-line testing, or from calibrations performed between two spectroscopic measurements. The interface to the application may be configured to provide metadata and / or calibration coefficients from the spectrometer module to the application. Metadata and / or calibration coefficients may be transferred from the firmware to the interface, for example, via the kernel and / or HAL.

[0029] A spectrometer comprises a spectrometer module. The spectrometer module may include hardware configured to receive electromagnetic radiation and generate measurement data. The term "measurement data" may refer to data obtained directly from the spectrometer module, or data derived from such data. Measurement data may include spectral data.

[0030] The term "spectral data" may refer to data that includes intensity values, each of which represents the intensity of electromagnetic radiation in at least a portion of its spectral range. Spectral data may therefore include a set of value pairs, each containing a value representing a spectral range, i.e., the wavelength or wavelength range of electromagnetic radiation, and a value representing the corresponding intensity of the electromagnetic radiation. Spectral data may include the direct output values ​​of a sensor, sometimes referred to as raw data, or it may include adjusted values, such as those corrected using calibration coefficients.

[0031] The spectrometer module may include a spectrometer module processor, which is an additional processor to the processor provided in the spectrometer. The spectrometer module processor may run the firmware of the spectrometer module. The firmware is described above. The spectrometer module may further include memory. The memory may store the firmware and / or calibration coefficients. The memory may be part of the spectrometer module processor. The spectrometer module processor may be a microcontroller or an application-specific integrated circuit (ASIC).

[0032] The processor is configured to determine whether calibration is required. The term "calibration" may refer to the operation of establishing a relationship between a quantitative value with measurement uncertainty provided by a measurement standard and the corresponding indication with associated measurement uncertainty of a calibrated spectrometer, in a first step, under specified conditions, and using this information to establish a relationship for obtaining measurement results from the indication, in a second step. Calibration can compensate for changes occurring in the spectrometer module, for example, due to slight changes in the relative positions of the components of the spectrometer module, changes due to expansion and contraction caused by temperature changes, or changes due to wear of components, such as photosensitive detectors within the spectrometer module. Thus, calibration can ensure that the spectrometer module outputs the same spectral data under the same illumination conditions, regardless of changing environmental conditions such as temperature or degradation of sensors over time. Calibration can therefore compensate for hardware-related changes, for example, by determining and applying a calibration coefficient.

[0033] The determination of whether calibration is required can be made based on a preset interval. For example, the determination may involve checking whether a preset interval has expired and, if so, triggering a calibration. The interval may be preset by the spectrometer manufacturer. Alternatively, the interval may be set by the application or user, for example, via an interface function call or by configuration settings, for example, a configuration file. The interval may be a time interval, for example, one calibration may be required every 24 hours or every 7 days. The interval may also be a number of measurements, for example, one calibration may be required after every 5 or 10 measurements.

[0034] The determination of whether calibration is required may be based on the type of measurement, which may refer to the object being measured and / or the purpose of the measurement. The determination may involve determining the degree of accuracy required for the type of measurement and triggering calibration if a preset degree of accuracy is exceeded. For example, a dataset may be provided in which each type of measurement is assigned a required degree of accuracy. For example, a medical measurement such as blood glucose measurement may require a higher degree of accuracy than a food analysis measurement in a supermarket. The degree of accuracy for each type of measurement may be stored in the spectrometer's memory, provided by an application via an interface, or obtained from a remote system, such as a cloud system, via a communication interface.

[0035] The determination of whether calibration is required can be made based on sensor data. Sensor data may include values ​​that have a potential impact on the spectrometer, i.e., values ​​that can cause signal drift. Sensor data can include temperature from a thermometer, humidity from a hygrometer, motion from a motion sensor such as a gyroscope, pressure from a pressure gauge, light from a light sensor, or chemical data such as the composition of ambient air from a spectrometer, which may be past measurements of the spectrometer being calibrated. For example, calibration may be triggered if one or more values ​​in the sensor data have changed compared to the sensor data since the last calibration. Sensor data can be obtained from sensors attached to or provided in the spectrometer. Alternatively, sensor data can be obtained from a remote system, such as a cloud system. The remote system can obtain sensor data from the spectrometer being calibrated or from different devices located in the same place. Sensor data can also be received from a central measurement station, such as a weather station.

[0036] The determination of whether calibration is required can be based on past measurement results of the spectrometer. For example, quality indicators such as the signal-to-noise ratio, signal correlation, or probability values ​​from a chemometric model indicating the likelihood that the components derived from the spectrum are correct can be extracted from past measurement results. The determination can be based on a single past measurement or on two or more past measurements.

[0037] The determination of whether calibration is required can be based on past calibration results. The determination can also be based on the distance between a past calibration and the calibration prior to it. For example, if a past calibration is close to the calibration prior to it, it may be determined that calibration is not required. Calibration may be required if the distance exceeds a certain distance, such as a preset value stored in the spectrometer or a value provided by the application via an interface.

[0038] The determination of whether calibration is required can be made based on the combination of the influencing factors described above. The determination can be made based on the combination of the interval and the type of measurement. The determination can be made based on the combination of the interval and the sensor data. The determination can be made based on the combination of the interval and the spectrometer's past measurement results. The determination can be made based on the combination of the interval and past calibration results. The determination can be made based on the combination of the type of measurement and the sensor data. The determination can be made based on the combination of the type of measurement and past measurement results. The determination can be made based on the combination of the type of measurement and past calibration results.

[0039] The determination may be based on a combination of sensor data and past spectrometer measurement results. The determination may also be based on a combination of sensor data and past calibration results. The determination may also be based on a combination of past spectrometer measurement results and past calibration results. A determination based on combinations may involve a score calculated by, for example, weighting and combining influencing factors. If the score exceeds a predetermined threshold, calibration may be required.

[0040] The determination of whether calibration is required can be triggered in various ways. The determination can be triggered by the spectrometer's startup routine. This can be particularly useful if the spectrometer is used only occasionally and therefore switched on and off periodically. The determination can be triggered hourly by a fixed time period, such as a hardware clock interrupt. The determination can be triggered through an application, such as an interface via a function call. Preferably, the determination is triggered by a request for measurement. Thus, in response to a measurement request, it is determined whether calibration is required, and if it is determined that calibration is required, the calibration is performed prior to the measurement. The code for determining whether calibration is required may be part of the operating system's HAL.

[0041] Calibration can be performed in various ways. Calibration may involve a reference target being measured in place of the sample. The reference target may have highly reproducible reflectivity behavior. The reference target may have high reflectivity within the wavelength range of the spectrometer, sometimes also referred to as a white reference target. Other reference targets, such as those having different characteristic reflectivity behavior for different wavelengths, may be used. The reference target may be a separate component that needs to be placed in front of the spectrometer. Alternatively, the spectrometer module may include the reference target. In this case, the spectrometer module may include an optical system capable of directing radiation from a radiation source to the reference target, and the optical system may further direct the radiation reflected by the reference target to a photosensitive detector.

[0042] Calibration can be performed by directing radiation from a radiation source directly to a photosensitive detector. The spectrometer module may therefore include an optical system, such as a mirror or lens, capable of directing radiation from the radiation source to the photosensitive detector. In the case of a mirror, the characteristic reflectivity of the mirror can be used for calibration. The spectrometer module may include a window, which partially transmits radiation from the radiation source to the sample and partially reflects radiation from the radiation source to the photosensitive detector. The window may include, essentially consist of, or be made of, optical glass, such as silica glass, phosphate glass, aluminosilicate glass, or silicon. Many of such materials exhibit Fresnel reflectivity, i.e., a window containing such material can often reflect radiation at a well-defined, temperature-independent ratio at a particular wavelength. During sample measurement, such reflected radiation can be subtracted from the measurement or blocked by an optical system, such as a shutter or aperture.

[0043] Calibration involving a reference target, or directing radiation from a radiation source directly onto the photosensitive detector, yields a detector signal that can be correlated to the known intensity of the incident radiation. This correlation can be used to generate a calibration coefficient. The calibration coefficient can then be used to correct the detector signal.

[0044] Calibration can be performed by avoiding any incident radiation to the photosensitive detector, which is sometimes called dark calibration. Avoiding incident radiation may involve removing any sample from the spectrometer, switching off the radiation source, or blocking any incident light, for example, by an aperture or shutter.

[0045] Alternatively, the spectrometer module may include one or more photosensitive detectors that never receive incident radiation, for example, by covering them with an absorbing or reflective material. The signal from a photosensitive detector that temporarily or permanently receives no incident radiation can be used as a background signal. The background signal can be subtracted from the signal during measurement. The background signal can also function to determine the calibration coefficient. The calibration coefficient can be used to correct the detector signal.

[0046] A spectrometer may be configured to allow two or more types of calibration, such as calibration with a reference target and dark calibration. The determination of whether calibration is required may further include determining which type of calibration is required. Such determination may be based on the above parameters for determining whether calibration is required. For example, the determination of which calibration is required may be based on a first preset time period for calibration with a reference target and a second preset time period for dark calibration.

[0047] In cases where calibration is triggered, any measurement request may be blocked, meaning it will not be passed to the spectrometer module before calibration is complete. Blocking can be achieved by placing any measurement request in a waiting queue until calibration is complete. Once calibration is complete, measurement requests from the waiting queue can be passed to the spectrometer module.

[0048] Measurement data may be passed to the interface. Measurement data may be read from the spectrometer hardware by the firmware. Measurement data may be passed to the operating system kernel, which may contain a driver for the spectroscopic module. The operating system kernel may pass the measurement data to the operating system HAL. The operating system HAL may further pass the measurement data to the interface. The interface may further pass the measurement data to the application that requested the measurement.

[0049] Measurement data may further encompass compositional data. Compositional data may be determined from spectral data. The term "compositional data" may refer to data relating to the composition of the measured object. Compositional data may include information on the content of one or more chemical compounds in an object, e.g., water, glucose, PET, or a group of chemical compounds, e.g., protein, starch, aromatic carbonized water. Compositional data may, alternatively or additionally, include information derived from the content of one or more compounds in the measured object, e.g., a person's fitness or health status, the maturity level of agricultural products, or the quality level of consumable materials, e.g., lubricants for machinery. Compositional data may also include recommendations based on the content of one or more compounds in the measured object, e.g., applying a certain fertilizer to measured soil based on its mineral content, or administering a certain dose of insulin based on blood glucose levels. Compositional data may further include values ​​indicating the confidence level of the determined information, e.g., percentages, where a high value indicates high confidence, e.g., that the sample is made from a certain plastic. The confidence level can be determined based on the deviation of the spectral data from the calibration sample, or the relative distance of the spectral data to calibration samples of different compositions.

[0050] Compositional data can be derived from spectral data by using a chemometric model. The term "chemometric model" can refer to a model that takes spectral data as input and outputs compositional data. A chemometric model can be a mechanism model, a data-driven model, or a hybrid model. A mechanism model can reflect a physical phenomenon in mathematical form, including, for example, a first-principles model. A mechanism model includes a set of equations that describe the interaction between a substance and electromagnetic irradiation, thereby giving rise to at least one target value and / or a model-based baseline value.

[0051] A chemometric model can be a data-driven model parameterized according to spectral data and can be trained using historical data. Historical data encompasses a dataset containing spectral data and associated chemometric data. Historical data can be obtained by measuring samples for which compositional data is available, for example from analytical measurements, or by subjecting samples to destructive laboratory techniques such as gas chromatography. The dataset can then be obtained by associating the obtained spectral data with compositional data obtained or derived from analytical measurements.

[0052] A data-driven model can be a classification model. A classification model can include at least one machine learning architecture and model parameters. For example, a machine learning architecture can be one or more of the following, or include them: linear regression, logistic regression, random forest, piecewise linear, nonlinear classifier, support vector machine, naive Bayes classification, nearest neighbor, neural network, convolutional neural network, generative adversarial network, support vector machine, or gradient boosting algorithm. In the case of a neural network, the model can be a multiscale neural network, or a recurrent neural network (RNN), such as a gated recurrent unit (GRU) recurrent neural network or a long short-term memory (LSTM) recurrent neural network, but is not limited to these.

[0053] A spectrometer may have access to one chemometric model or two or more chemometric models. In the case of two or more chemometric models, each chemometric model can be optimized for a specific use case, for example, one optimized to determine blood glucose from skin measurements, one to determine acid in fruit, and another to determine protein in feed.

[0054] The chemometric model used for a particular measurement may be selected by the application. The application may submit parameters indicating the chemometric model to be used as part of the measurement request to the interface. Alternatively, the application may set global variables, for example, in a configuration file, for a set of measurements or all of those measurements. This may make sense if a single application is dedicated exclusively to a particular use case.

[0055] Alternatively, the chemometric model may be selected by the spectrometer. The processor may be configured to select a chemometric model to derive compositional data from spectral data based on additional sensor data. For example, the spectrometer may receive an optical image of the sample. This can be particularly useful if the spectrometer is part of a smartphone equipped with a camera. The image can be analyzed to detect the type of sample, for example, shape, color, or surface gloss may be extracted from the image and compared to baseline values ​​for different samples for which a chemometric model is available. The spectrometer may select a chemometric model based on the closest fit. If a suitable chemometric model is not found, an error message may be generated and passed to the application via the interface. The error message may prompt the application to provide sample information or repeat the measurement request.

[0056] The selection of a chemometric model may be based on a machine learning model. The machine learning model may take one or more of the following as inputs: the user using the spectrometer, the time of day, sample history, motion data from each sensor, temperature, and ambient light. The machine learning model may have either the sample type or a chemometric model as an output. The machine learning model may be pre-trained or learn based on user feedback.

[0057] A spectrometer comprises a spectrometer module configured to receive electromagnetic radiation. The term "electromagnetic radiation" may refer to radio waves, microwaves, infrared light, visible light, ultraviolet light, X-rays, or gamma rays. Infrared light may be near-infrared with wavelengths of 0.75–1.4 μm, short-wavelength infrared with wavelengths of 1.4–3 μm, mid-wavelength infrared with wavelengths of 3–8 μm, long-wavelength infrared with wavelengths of 8–15 μm, or far-infrared with wavelengths of 15–1000 μm. For example, a spectrometer module may be configured to receive electromagnetic radiation with wavelengths of 1–3 μm.

[0058] A spectrometer module may include a radiation source. The term "radiation source" may refer to a device that generates and / or emits electromagnetic radiation, for example, electromagnetic radiation within the wavelength range described above. The radiation source may be configured to illuminate an object. The radiation source may be, or comprise, a thermal radiator or a semiconductor-based radiation source. At least one semiconductor-based radiation source may be a light-emitting diode (LED) or a laser, particularly a laser diode. A thermal radiator may be an incandescent lamp or a thermal infrared emitter.

[0059] A spectrometer module is configured to generate measurement data, particularly spectral data. A spectrometer module may include a photosensitive detector. The term "photosensitive detector" may refer to a device that generates an electrical signal in response to the reception of electromagnetic irradiation. A photosensitive detector may include one or more photosensitive regions, each of which may generate a separate electrical signal indicating the intensity of the electromagnetic irradiation impacting the region.

[0060] The photodetector may be an inorganic camera element such as an inorganic camera chip, CCD chip, or CMOS chip. The photodetector may include a photoconductive material, particularly an inorganic photoconductive material, which may be selected from lead sulfide (PbS), lead selenide (PbSe), germanium (Ge), indium gallium arsenide (InGaAs, including but not limited to extended InGaAs, i.e., InGaAs exhibiting a spectral response up to 2.6 μm), indium antimonide (InSb), or mercury cadmium telluride (HgCdTe or MCT).

[0061] A photosensitive detector may include multiple photosensitive regions, such as an array of photosensitive regions, where electromagnetic radiation of different wavelengths collides with the photosensitive regions. For this reason, a spectrometer module may include a dispersive element such as a prism or a grating. The spectrometer may include one or more optical filters, such as a linear variable filter or multiple filters that transmit different wavelengths of electromagnetic radiation to different photosensitive regions. The dispersive elements or filters may be arranged so that electromagnetic radiation of different wavelengths collides with multiple photosensitive regions. A photosensitive detector may include multiple photosensitive regions, where the photosensitive regions are covered by filters that transmit electromagnetic radiation of different wavelengths.

[0062] A photosensitive detector may encompass only one photosensitive region. Light of different wavelengths may collide with this single photosensitive region at different times. For this reason, a spectrometer module may include an interferometer, such as a Michelson interferometer. The interferometer may be positioned to receive incident electromagnetic radiation and direct the electromagnetic radiation that has passed through the interferometer towards the photosensitive region. Since the interferometer may also be placed between the radiation source of the spectrometer module and the object being measured, the wavelength of the electromagnetic radiation received by the spectrometer module will vary over time.

[0063] The electrical signal from the detector can be analog or digital. If it is analog, it can be converted to a digital signal. Therefore, the spectrometer module may include an analog-to-digital converter (ADC). The spectrometer module may also include a controller. The controller may include ADC functionality. The controller may provide spectral data. The spectral data may include some or all of the electrical signal. The spectral data may further include the wavelength or wavelength range of the electromagnetic radiation associated with the electrical signal. Information regarding the wavelength or wavelength range can be obtained, for example, by identifying which photosensitive region the electrical signal originates from and by providing filter information for a filter on a particular photosensitive region, through stored values ​​indicating the wavelength or wavelength range for that photosensitive region.

[0064] The spectrometer comprises a processor configured to trigger the spectrometer module to perform spectroscopic measurements in response to requests received via an interface. The processor may be configured to perform the above-described functionality of the spectrometer. The processor may execute program code to perform functionality, for example, by forwarding requests from the interface to the spectrometer module. The program code may include code for the interface. The program code may further include code for the HAL and kernel. Alternatively, or additionally, the processor may be configured to execute code that triggers the execution of some or all of the functionality on a remote computer via a communication interface. The remote computer may be part of a cloud computing environment.

[0065] In another aspect, the present invention relates to a portable device encompassing a spectrometer according to the present invention. The term “portable device” may refer to a device having dimensions and weight that allow a person to carry the portable device without significant physical effort. The portable device may be a smartphone, tablet, or wearable. The wearable may be a wristwatch, wristband, hearing aid, ring, belt, necklace, ankle band, thigh band, or forearm band. The spectrometer may be fully integrated into the portable device, i.e., all parts of the spectrometer are contained within the portable device. Parts of the spectrometer, such as a processor, may be shared with other functionalities within the portable device.

[0066] Alternatively, one or more components of the spectrometer may be physically located outside the portable device or be communicatively coupled to the portable device. The portable device may include a communication interface, such as a telecommunications interface or a Bluetooth interface. The communication interface may enable data flow between the spectrometer components outside the portable device and the portable device. The portable device may be communicatively connected to a cloud computing system. The cloud computing system may perform some or all of the spectrometer's data processing, for example, deriving compositional data from spectral data. The portable device can send spectral data to the cloud system via the communication interface, and the cloud system may derive compositional data from the spectral data, for example by using a chemometric model, and send the compositional data back to the portable device.

[0067] The spectrometer module may be a separate spectrometer module device, such as a handheld measuring head. The spectrometer module device may be communicatively coupled to a portable device, for example, by a Bluetooth interface. The portable device may send measurement requests from an application to the spectrometer module device via the communication interface. The spectrometer module device may send spectral data to the portable device via the communication interface. [Brief explanation of the drawing]

[0068] [Figure 1] This document illustrates an embodiment of the data flow in the spectrometer of the present invention. [Figure 2] A more detailed embodiment of the data flow in the spectrometer of the present invention is shown. [Figure 3] An example for a portable device with an integrated spectrometer module is shown. [Figure 4] An example is shown for a portable device that is communicatively coupled to a spectrometer module. [Modes for carrying out the invention]

[0069] Figure 1 shows an embodiment of the data flow in the spectrometer (100) of the present invention. The spectrometer (100) includes an interface (101) to an application (110). The interface may be an API that includes function calls. The interface (101) may receive a measurement request (111) from the application (101). The measurement request (111) may be a function call provided by an API provided to trigger a measurement in the spectrometer (100), e.g., spectrometer.startMeasurement(). The measurement request (111) may additionally include parameters, such as measurement variables, e.g., sample time. The measurement request (111) may be transferred from the interface (101) to the spectrometer module (102). Such a transfer may be achieved by a spectrometer processor not shown in Figure 1.

[0070] The spectrometer may determine whether calibration is required (104). The determination may be triggered by a measurement request (111). The determination may be based on the interval, i.e., how long ago the last calibration was performed, the type of measurement, sensor data, past measurement results, past calibration results, or a combination thereof.

[0071] The spectrometer module performs measurements upon request and provides spectral data (103) in cases where the measurement is successfully completed. The measurement data (103) may include spectral data. The spectral data may be an array of value pairs, each pair including the wavelength or wavelength range of electromagnetic radiation and the intensity of electromagnetic radiation at that wavelength or wavelength range. The spectral data may relate to uncorrected measurements or corrected values, such as values ​​corrected based on a calibration coefficient.

[0072] The measurement data (103) may further include compositional data. Compositional data may be obtained based on spectral data using a chemometric model. The chemometric model may be parameterized according to the spectral data so that it can take spectral data as input and output compositional data. Since there may be two or more chemometric models available, the application (100) may have already selected one, for example, as a parameter of the measurement request or via a registration file. The interface (101) may provide a selection of a chemometric model to be used to determine the compositional data. For example, the application (100) may be intended to display the sugar content of an apple to the user. The application (100) may therefore provide the interface (101) with the information that the sugar content of the apple is to be determined. The interface (101) may provide the application (110) with appropriate function calls, setup values, or files. An appropriate chemometric model may be selected based on the information provided to the interface (101). A chemometric model can output compositional data, such as sugar content in g / kg, and a confidence level indicating the expected accuracy and / or precision of the measurement results.

[0073] The interface (101) can receive measurement data (103) and transfer it to the application. This can be achieved by returning such data or a pointer to such data to the measurement request. Alternatively, the interface (101) can use the data because the application (110) can write the measurement data (103) to a location in memory where it has read access.

[0074] Figure 2 shows a more detailed embodiment of the data flow in the spectrometer (200) of the present invention. The description in Figure 1 applies to Figure 2 to the extent that the components correspond to the components in Figure 1. The interface (201) can receive a measurement request (211) from an application (210). The measurement request (211) can be forwarded to the hardware abstraction layer HAL (202). The HAL can determine whether calibration is required, and if it determines that calibration is required, it forwards a calibration request (207) to the kernel. The kernel can forward the calibration request (211) to the spectroscopic module (204), for example, by using an appropriate spectroscopic module driver built into the kernel. The spectroscopic module (204) can receive the calibration request (207) via its firmware (205). The firmware (205) can trigger the spectroscopic hardware (206) to perform the calibration. Once the calibration is complete, the firmware (205) can collect calibration data (208) and provide it to the kernel (203).

[0075] Alternatively, the firmware (205) internally stores the calibration data and returns only a message to the kernel (203) indicating the completion of the calibration. The firmware (205) can achieve this by writing to the registers of the spectroscopic module (204), which can be read by the spectroscopic module driver built into the kernel (203). The kernel (203) may pass the calibration data (208) or the completion message to the HAL (202). The HAL (202) may update the calibration coefficients.

[0076] Depending on the completed calibration, HAL(202) may forward the measurement request (211) to the kernel(203). The kernel may forward the measurement request (211) to the spectroscopic module (204), for example by using an appropriate spectroscopic module driver built into the kernel. The spectroscopic module (204) may receive the measurement request (211) via its firmware(205). The firmware(205) may trigger the spectroscopic hardware(206) to perform the measurement. Once the measurement is complete, the firmware(205) may collect the measurement data (209) and provide it to the kernel(203). The firmware(205) can achieve this by writing to a register in the spectroscopic module(204), which can be read by the spectroscopic module driver built into the kernel(203).

[0077] The kernel (203) may pass the measurement data (209) to the HAL (202). The HAL may contain code for one or more chemometric models to obtain compositional data from the spectral data contained within the measurement data (209). The HAL may add or replace the compositional data with the spectral data in the measurement data (209). The HAL may pass the measurement data (209) to the interface (201), which makes the measurement data (209) available to the application (210) that sent the measurement request (211).

[0078] Figure 3 shows an example for a portable device (300) having an integrated spectrometer module (310). The portable device (300) may be a wearable such as a smartphone, tablet, or smartwatch. The spectrometer module (310) may include illumination (311). Illumination (311) may be a light source, such as an incandescent lamp or LED. The light source may produce electromagnetic radiation in a desired range, such as the near-infrared range. Illumination (311) may further include an optical system, such as lenses, mirrors, and / or apertures, to direct the electromagnetic radiation from the light source to an object. Illumination (311) may be communicatively coupled to a controller (313). The controller may be powered, for example, from the battery of the portable device (300), and may switch the light source of illumination (311) on and off as needed.

[0079] The spectrometer module may further include a detector (312). The detector (312) may generate an electrical signal in response to electromagnetic irradiation striking the sensor.

[0080] The detector (312) may include an array of photosensitive regions. Each photosensitive region may be covered by a filter so that electromagnetic radiation of a wavelength or wavelength range dedicated to it strikes the photosensitive region. The photosensitive regions may be sensitive in a wavelength region of interest, e.g., the near-infrared region. The photosensitive regions may include a photoreceptor, e.g., PbS or PbSe. The photosensitive regions may generate a current that indicates the intensity of the electromagnetic radiation striking them. The detector (312) may include an optical system for collecting the maximum amount of incident electromagnetic radiation. The optical system may include mirrors, lenses, and / or apertures.

[0081] The detector (312) may be communicatively coupled to the controller (313). The controller (313) may collect one or more signals from the detector (312) and transfer them to the processor (330). The controller (313) may convert one or more signals from analog to digital. This can be achieved, for example, by integrating the currents obtained from each photosensitive region and providing the resulting values ​​in digital form. By combining these values ​​with the origin of the photosensitive regions, each of which measures electromagnetic radiation at a specific wavelength or wavelength range, the controller (313) may collect spectral data and transfer them to the processor (330).

[0082] The processor (330) may execute code for the above method. The processor (330) may obtain code from memory (320). In this example, the processor (330) may execute both spectrometer code, for example, determination of compositional data based on spectral data by executing a chemometric model, and an application that receives both compositional data and spectral data from the spectrometer interface. The portable device (300) further includes a display (340) for collecting user input and may display measurement results, for example, via a graphical user interface (GUI).

[0083] Such a GUI may be part of an application that uses compositional and / or spectral data. The GUI may also be part of the spectrometer's interface and may be contained within an API provided by the spectrometer, for example, which the application can use and / or adjust for that purpose.

[0084] Figure 4 shows an example for a portable device (400) communicatively coupled to a spectrometer module (450). The description in Figure 3 applies to Figure 4 to the extent that the components correspond to the components in Figure 3. The spectrometer module (450) may include an illumination (451) for illuminating a sample in a desired wavelength range. A detector (452) may receive electromagnetic radiation from the sample and generate a signal indicating the intensity of the electromagnetic radiation hitting the detector. A controller (453) may be communicatively coupled to the illumination (451) and the detector (452). The controller (453) may supply power to the illumination (451) and the detector (452), switch the illumination (451) on and off as needed, read out a detector signal from the detector (452), and / or convert the detector signal from analog to digital.

[0085] The spectrometer module (450) may further include a communication interface (454). The communication interface (454) may be communicatively coupled to a controller (453). The communication interface (454) may receive measurement requests and transmit spectral data to a portable device (400). The portable device (400) may include a communication interface (430) to transmit measurement requests and receive spectral data from the spectrometer module (450). The communication interfaces (430, 450) may be cables, such as USB cables, or wireless communication interfaces, such as infrared communication interfaces, Bluetooth interfaces, wireless LAN interfaces, or telecommunication interfaces.

[0086] The portable device (400) may include a processor (420), for example, a CPU, which is communicatively coupled to a communication interface (430) and memory (410). The processor (420) may execute code stored in memory (410). The processor (420) may execute code for an application that submits measurement requests to the interface. The processor (420) may execute code for the interface and / or to obtain compositional data from spectral data. The portable device (400) may include a display (440), which may display a GUI to receive input, trigger measurements, and / or display the results of measurements. The GUI may be part of an application or part of an interface that provides such functionality to an application as an API.

[0087] Other variations of the disclosed embodiments can be understood and practiced by those skilled in the art in practicing the claimed invention, based on the drawings, this disclosure, and the accompanying study of the claims.

[0088] For the processes and methods disclosed herein, the actions performed in the processes and methods may be performed in different orders. Furthermore, the actions outlined are provided only as examples, and some of the actions may be optional, combined with fewer steps and actions, supplemented with further actions, or extended with additional actions, without departing from the essence of the disclosed embodiments.

[0089] In the claims, the word “equipped with” does not exclude other elements or processes, and the indefinite article “a” or “an” does not exclude plurals. A single unit or apparatus may perform the functions of several items described in the claims. The mere fact that certain means are described in different dependent claims does not imply that combinations of these means cannot be used advantageously.

Claims

1. a. An interface to an application, wherein the interface is configured to receive a request to perform a spectroscopic measurement and to provide the measurement data to the application. b. A spectrometer module configured to receive electromagnetic radiation and generate measurement data based on said electromagnetic radiation, and c. A processor configured to determine whether calibration is required, and, if the determination indicates that calibration is required, to trigger the spectrometer module to perform calibration. A spectrometer equipped with the following features.

2. The spectrometer according to claim 1, wherein the processor is configured to determine whether calibration of the spectrometer is required in response to a measurement request, and if the determination indicates that calibration is required, to trigger the spectrometer module to perform calibration before triggering the spectrometer module to perform a spectroscopic measurement.

3. The spectrometer according to claim 1 or 2, wherein the determination of whether calibration is required is based on a preset interval, a type of measurement, sensor data, past measurement results of the spectrometer, or past calibration results.

4. The spectrometer according to claim 1 or 2, wherein the spectrometer is configured to enable two or more types of calibration, and determining whether calibration is required further includes determining which type of calibration is required.

5. The spectrometer according to claim 1 or 2, wherein the measurement data includes spectral data and compositional data.

6. The spectrometer according to claim 1 or 2, wherein the spectrometer module is configured to receive electromagnetic radiation with a wavelength of 1 to 3 μm.

7. The spectrometer according to claim 1 or 2, wherein the spectrometer module includes a photosensitive detector that includes a plurality of photosensitive regions, the photosensitive regions are covered by a filter, and the filter transmits electromagnetic radiation of different wavelengths.

8. A portable device comprising the spectrometer described in claim 1 or 2.

9. The portable device according to claim 8, wherein the portable device is a smartphone, tablet, or wearable, and the spectrometer is fully integrated into the portable device.

10. a. Receiving requests to perform spectroscopic measurements via an interface to the application. b. In response to the above request, determine whether calibration is required, and if the determination indicates that calibration is required, trigger the spectrometer module to perform calibration. c. Triggering the spectrometer module to perform a spectroscopic measurement. d. Receiving measurement data from the spectrometer module, and e. Providing the measurement data to the application via the interface. A method for performing spectroscopic analysis, including [specific details omitted].

11. The method according to claim 10, wherein the interface is configured to receive measurement requests from two or more applications.

12. The method according to claim 10 or 11, wherein the interface is an application programming interface or includes an application programming interface.

13. A non-temporary computer-readable medium, when executed by one or more processors, includes instructions that cause the one or more processors to determine whether calibration is required, and, if the determination indicates that calibration is required, to trigger a spectrometer module to perform calibration.

14. A method for using measurement data obtained by a spectrometer or method according to claim 1 or 2 to provide the composition of an object or a recommendation for acting on the object based on its composition.

15. The method according to claim 14, wherein the measurement data is used in an application that makes available to a user fitness and health information, information on agricultural products, information on food or feed, or information related to recycling.

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