Patent Description:
An analysis of samples related to clinics or the environment is achieved through a biochemical, chemical, or mechanical treatment process. Recently, the development of techniques for diagnosing or monitoring a biological sample has drawn a significant interest. The application of a molecular diagnosis method based on nucleic acid has significantly increased recently in the fields of diagnosing an infectious disease or cancer, pharmacogenomics, or developing a new medicine due to its high accuracy and sensitivity. A fine particle device is widely used for simply and precisely analyzing a sample according to various purposes. <CIT> relates to an active sieve device for the isolation and characterization of bio-analytes, comprising a substrate for supporting the bio-analytes. The substrate comprises a plurality of interconnections and a plurality of regions, each region comprising a hole and at least one electrode embedded in or located on the substrate and electrically associated with the hole. Each region further comprises at least one transistor integrated in the substrate and operably connected to the at least one electrode and to at least one of the plurality of interconnections. <CIT> relates to a dielectric sheet which is arranged between a pair of electrodes for forming an electric field in a cell that stores therein a sample having particles dispersed movably in a medium, the dielectric sheet being formed to include multiple mutually parallel slits to form a diffraction grating, and a parallel light flux is applied to the diffraction grating to generate diffracted light. A gradient electric field in the vicinity of the slits generated by applying a voltage between the pair of electrodes causes the particles to migrate in such a manner as to cover the slits or away from the slits and thereby the contrast of the diffraction grating to vary, and whereby the diffusion coefficient and/or size of the particles can be calculated from the temporal change of the diffracted light when the particles diffuse freely after stopping the application of the voltage. <CIT> relates to a high efficiency and high sensitivity particle capture type terahertz sensing system. The particle capture type terahertz sensing system includes a sensing substrate to capture particles, and a terahertz sensor to emit terahertz electromagnetic waves to the sensing substrate to sense the particles, wherein the sensing substrate includes a base substrate and a particle capture structure layer formed on the base substrate, the particle capture structure layer includes a plurality of slits for focusing the terahertz electromagnetic waves, the particle capture structure layer captures the particles in the plurality of slits using dielectrophoresis, and an area in which the terahertz electromagnetic waves converge to the plurality of slits matches an area in which the particles are captured in the plurality of slits through the dielectrophoresis.

It is the object of the present invention to enable an improved detection of fine particles. This object is solved by the subject matter of the independent claims which define the present invention.

One or more example embodiments provide an apparatus and method for detecting fine particles, and more specifically, to an apparatus and method for quantifying fine particles through spectral analysis.

According to an aspect of an example embodiment, there is provided an apparatus configured to detect fine particles, including a fine particle trap including a plurality of through holes that are configured to trap the fine particles, a measurer including a light source configured to emit light to the plurality of through holes, and a detector configured to detect light scattered, reflected, or transmitted through the plurality of through holes and measure a spectrum, and a processor configured to estimate a number of the fine particles trapped in the plurality of through holes based on of the measured spectrum, wherein the plurality of through holes have a diameter equal to or less than <NUM> (micrometer).

The fine particle trap may further include an inlet through which a sample is injected, a channel through which the injected sample moves and an outlet through which the sample is discharged, and the plurality of through holes may be formed to penetrate in a direction perpendicular to a length direction of the channel such that the sample moving along the channel is trapped.

The fine particles may be trapped in the through holes by at least one of capillarity, dielectrophoresis, or photothermal effect.

The fine particle trap may further include an alternating current (AC) electrode configured to induce the dielectrophoresis based on a control of the processor.

The fine particle trap may further include a heat source configured to generate the photothermal effect based on a control of the processor.

The plurality of through holes may be provided to have photonic crystals.

A shape of each of the plurality of through holes and a size of each of the plurality of through holes may be determined based on at least one of a shape of each target fine particles, a size of each target fine particles, or a type of each target fine particles.

The processor may be further configured to extract one or more features from the spectrum and estimate the number of the fine particles based on the extracted features using a fine particle estimation model.

The processor may be further configured to extract the one or more features from the spectrum using a principal component analysis (PCA).

The one or more features may include a feature of at least one of a first principal component extracted from the spectrum through the PCA and a second principal component extracted from the spectrum through the PCA.

The processor may be further configured to determine whether to perform calibration and, based on determining to perform calibration, calibrate the fine particle estimation model using one or more reference particles.

Based on the one or more reference particles being trapped in the plurality of through holes, the processor may be further configured to control the measurer to obtain a plurality of calibration spectra and train the fine particle estimation model based on the obtained plurality of calibration spectra.

According to another aspect of an example embodiment, there is provided a method of detecting fine particles, including trapping the fine particles in a plurality of through holes, emitting, by a light source, light to the plurality of through holes, detecting, by a detector, light scattered, reflected, or transmitted through the plurality of through holes, measuring, by the detector, a spectrum based on the detected light, and estimating, by a processor, a number of the fine particles trapped in the plurality of through holes based on the measured spectrum, wherein the plurality of through holes have a diameter equal to or less than <NUM>.

The method may further include controlling, by the processor, an alternating current (AC) voltage of a fine particle trap to induce the dielectrophoresis.

The method may further include controlling, by the processor, a heat source included in a fine particle trap to generate the photothermal effect.

The estimating of the number of the fine particles may include extracting one or more features from the spectrum and estimating the number of the fine particles based on the extracted features using a fine particle estimation model.

The extracting of the one or more features may include extracting the one or more features from the spectrum using a principal component analysis (PCA).

The method may further include determining whether to perform calibration, and calibrating the fine particle estimation model using one or more reference particles based on determining to perform calibration.

The calibrating of the fine particle estimation model may include trapping the one or more reference particles in the plurality of through holes, obtaining a plurality of calibration spectra, and training the fine particle estimation model based on the obtained plurality of calibration spectra.

Embodiments will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings in which:.

Details of example embodiments are included in the following detailed description and drawings. Advantages and features of the disclosure, and a method of achieving the same will be more clearly understood from the following embodiments described in detail with reference to the accompanying drawings.

Also, the singular forms are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that when an element is referred to as "comprising" another element, the element is intended not to exclude one or more other elements, but to further include one or more other elements, unless explicitly described to the contrary. In the following description, terms such as "unit" and "module" indicate a unit for processing at least one function or operation and they may be implemented by using hardware, software, or a combination thereof.

<FIG> is a block diagram illustrating an apparatus configured to detect fine particles according to an example embodiment. <FIG> are structural diagrams of a fine particle trap according to example embodiments. <FIG> are diagrams illustrating examples of quantifying fine particles through spectrum analysis.

Referring to <FIG>, an apparatus <NUM> configured to detect fine particles includes a fine particle trap <NUM>, a measurer <NUM>, and a processor <NUM>.

When a sample is injected, the fine particle trap <NUM> may trap target fine particles. The sample may include respiratory secretions, or bio-fluids including at least one of blood, urine, perspiration, tears, saliva, etc., or a swab sample of an upper respiratory tract, dust in the atmosphere, or a solution of the bio-fluid, the dust, or the swab sample dispersed in other medium. In this case, the other medium may include water, saline solution, alcohol, phosphate buffered saline solution, vital transport media, etc., but is not limited thereto. The target fine particles may include ribonucleic acid (RNA), deoxyribonucleic acid (DNA), peptide nucleic acid (PNA), locked nucleic acid (LNA), virus (e.g., RNA virus, DNA virus, PNA virus, LNA virus), or duplex of one or two or more types of LNA virus, bacteria, pathogens, germs, oligopeptides, proteins, toxin, particulate matter, etc., but are not limited thereto. The term "particulate matter" may refer to tiny particles suspended in the air that can be inhaled into lungs and cause various health problems.

<FIG> is a plan view illustrating a structure of the fine particle trap <NUM>. <FIG> are front views of the structure of the fine particle trap <NUM>.

The fine particle trap <NUM> may include an inlet <NUM> through which a sample is injected into a substrate <NUM>, a channel <NUM> through which the injected sample moves, and an outlet <NUM> through which the sample is discharged. The fine particle trap may further include a chamber <NUM> in which fine particles included in the sample are trapped when the sample moves along the channel <NUM>.

The substrate <NUM> may be formed of an inorganic material, such as silicon (Si), glass, polymer, metal, ceramic, graphite, etc., or a material such as acrylic-based material, polyethylene terephtalate (PET), polycarbonate, polystylene, polypropylene, silicon nitride (SixNy), titanium oxide (TiO2), silicon oxide (SiO2), etc. The substrate <NUM> may include a function layer configured to adjust optical characteristics. For example, the substrate <NUM> may be treated with gold (Au), or antireflection coating, hydrophilic/hydrophobic coating, antigen-antibody treatment, or aptamer treatment may be performed on the substrate <NUM>.

The substrate <NUM> may have a predetermined thickness. The thickness of the substrate <NUM> may vary without limitation in consideration of the type and size of the target fine particles and thermal conductivity used for each layer of the substrate <NUM>. The term "fine particle" may refer to a particle having a size of <NUM> or less in diameter. The substrate <NUM> may be formed of multiple layers. For example, the substrate <NUM> may include a first layer in which the inlet <NUM>, the channel <NUM>, and the outlet <NUM> are formed and a second layer in which the chamber <NUM> is formed. A third layer may be formed below the second layer. The layers may be integrally formed of the same material, or may be separately formed of the same material or different materials and bonded to one another. For example, each layer may be formed of a material having a different thermal conductivity. For example, the first to third layers may be formed of a material that has thermal conductivity increasing stepwise from in the first layer to in the third layer. According to another example embodiment, the second layer and the third layer may be formed of a material having the same thermal conductivity that is greater than a thermal conductivity of the first layer.

The inlet <NUM> and the outlet <NUM> may be formed to communicate with the channel <NUM>. The cross-sectional diameter of the inlet <NUM> connected to the channel <NUM> may be equal to or smaller than the cross-sectional diameter of the channel <NUM>, but embodiments are not limited thereto. The inlet <NUM> may be irregularly formed such that its cross-section gradually increases or decreases toward the channel <NUM>, but embodiments are not limited thereto. The cross-section of the inlet <NUM> may have various shapes, such as, for example, a circular shape, an elliptical shape, a hexagonal shape, a triangular shape, and the like. The outlet <NUM> may include an absorbent pad that may move and drain a solution using capillarity. In this way, a movement speed of the solution may be more easily controlled.

A filter may be further disposed in the channel <NUM> at a position in front and/or at the rear of the chamber <NUM> to pass particles having a predetermined size or less. The filter may include, for example, silicon, polyvinylidene fluoride (PVDF), polyethersulfone, polycarbonate, glass fiber, polypropylene, cellulose, mixed cellulose esters, polytetrafluoroethylene (PTFE), polyethylene terephthalate, polyvinyl chloride (PVC), nylon, phosphocellulose, diethylaminoethyl cellulose (DEAE), and the like, but embodiments are not limited thereto. Holes may have various shapes, such as, for example, a circular shape, a square shape, a slit shape, an irregular shape by glass fiber, and the like.

The chamber <NUM> may include a plurality of through holes <NUM>. Tens of or more through holes <NUM> may be provided. Each through hole <NUM> may have a diameter that is equal to or less than <NUM> to trap fine particles one-by-one. The through holes <NUM> may be formed to penetrate in a direction perpendicular to the length direction of the channel <NUM>, that is, in a direction from the first layer to the second layer of the substrate <NUM>, as shown in <FIG>. The through holes <NUM> may have a constant cross-section. The cross-section of the through hole <NUM> may have various shapes, such as, for example a hexagonal shape, a rectangular shape, a triangular shape, a circular shape, and the like. For example the through hole <NUM> may be formed as a hexagonal cavity, a rectangular cavity, a circular cavity, a circular cavity, or the like.

The plurality of through holes <NUM> may be grouped into two or more through hole groups having different shapes or sizes to trap two or more types of fine particles having different sizes or shapes. In this case, the through hole groups may be arranged in the order of size so that gradually larger particles can be trapped along the movement direction of the sample. The number and arrangement of the through holes and the size and shape of each through hole are not limited, and may vary depending on the shape, size, type, and the like of the target fine particles.

When the sample injected through the inlet <NUM> moves along the channel <NUM>, the fine particles included in the sample may be trapped in the through holes <NUM> by capillarity. The plurality of through holes <NUM> may be arranged in an NxM multi-dimensional array. In this case, N and M are integers greater than or equal to <NUM>, which may be the same or different numbers. By using the multi-dimensional array, the fine particles of the sample may be trapped into the through holes <NUM> by capillarity at a higher speed. The through holes <NUM> may be arranged to have photonic crystals by adjusting the arrangement spacing of all or some of the plurality of through holes <NUM>.

Referring to <FIG>, the fine particle trap <NUM> may further include an alternating current (AC) electrode <NUM>. The AC electrode <NUM> may be disposed inside or outside of the channel <NUM>, or may be disposed on an outer surface of the channel <NUM> in an array form. According to another example embodiment, the AC electrode <NUM> may be disposed on an inner surface or outer surface of the through hole <NUM>. The AC electrode <NUM> may apply an AC voltage to the fine particle trap <NUM> under the control of the processor <NUM>, and allow the fine particles in the sample to be trapped in the through holes <NUM> by dielectrophoresis induced through the applied AC voltage.

Referring to <FIG>, the fine particle trap <NUM> may further include a heat source <NUM>. The heat source <NUM> may be a light source configured to emit light to the plurality of through holes <NUM> of the chamber <NUM>. The light source may emit laser light. However, embodiments are not limited thereto. Light emitted by the light source may be converted into heat to induce a photothermal effect, and the fine particles in the sample may be quickly trapped in the plurality of through holes <NUM> by the photothermal effect. The heat source <NUM> may be formed as an electrical heating element.

A photothermal film configured to convert light into heat may be attached to the interior of the chamber <NUM>, the interior of the substrate <NUM>, or the entire or part of the bottom surface of the substrate <NUM>. The thickness of the photothermal film is not particularly limited, and may be appropriately modified in consideration of characteristics of a material used as the photothermal film, such as thermal conductivity or heat retention. The photothermal film may be formed of a material, such as polymer, metal, metal oxide, nanocomposite, nanostructure, semiconductor, or the like. For example, a polyimide (PI) film, a gold (Au) film, or an aluminum nanostructure (AINS) film may be used.

The fine particle trap <NUM> may further include a temperature sensor. The temperature sensor may measure a temperature of through holes <NUM> heated by the heat source <NUM> and send the measured temperature to the processor <NUM>. The processor <NUM> may control the heat source <NUM> based on the measured temperature so that the plurality of through holes <NUM> maintain a constant temperature.

The fine particle trap <NUM> may include both the electrode <NUM> and the heat source <NUM>. The processor <NUM> may selectively or simultaneously control the electrode <NUM> and the heat source <NUM> so that the fine particles can be more effectively trapped in the plurality of through holes by capillarity, dielectrophoresis, and photothermal effect. However, embodiments are not limited thereto, and the fine particle trap <NUM> may further include an active and/or passive driving device, such as a passive vacuum void pump, a syringe pump, a vacuum pump, a pneumatic pump, and the like, and/or a structure used for moving the solution, such as an electro-wetting device.

Referring back to <FIG>, the measurer <NUM> may include a light source <NUM> and a detector <NUM>. When the fine particles are trapped in the plurality of through holes <NUM>, a transmission, scattering, or reflection spectrum may be measured from the plurality of through holes <NUM> by using the light source <NUM> and the detector <NUM>.

The light source <NUM> may be one of, for example, a light emitting diode (LED), a vertical-cavity surface-emitting laser (VCSEL), a laser diode (LD), a tungsten lamp, a fluorescent lamp, a halogen lamp, a mercury lamp, a xenon lamp, a metal halide lamp, or a combination thereof. A wavelength band of the light emitted by the light source <NUM> is nor particularly limited.

The detector <NUM> may detect light scattered, reflected, or transmitted through the plurality of through holes. The detector <NUM> may include, for example, a photomultiplier tube, a photo detector, a photomultiplier tube array, a photo detector array, a complementary metal-oxide semiconductor (CMOS) sensor, or a spectrometer.

The light source <NUM> and the detector <NUM> may be disposed in opposite directions relative to each other with respect to the plurality of through holes. In this way, when the light emitted to the plurality of through holes <NUM> by the light source <NUM> passes through the plurality of through holes <NUM>, the measurer <NUM> may use the detector <NUM> to detect the light that has passed through the holes and obtain a transmission spectrum based on the detected light. However, the arrangement structure is not limited those illustrated in the drawings, and may be variously modified in consideration of the type and size of the fine particles, structural limitations of the device <NUM>, and the like. When the light source <NUM> is arranged in the same direction as the heat source <NUM> of the fine particle trap <NUM>, the light source <NUM> and the heat source <NUM> may be unitarily formed, or a part of the light source <NUM> may be used as the heat source <NUM>.

The processor <NUM> may control the fine particle trap <NUM> and the measurer <NUM>, and estimate the number of fine particles trapped in the plurality of through holes <NUM> based on the spectrum measured by the measurer <NUM>.

For example, the processor <NUM> may control the electrode <NUM> and/or the heat source <NUM> such that the fine particles in the sample can be more rapidly trapped in the plurality of through holes by the capillarity, dielectrophoresis, and/or photothermal effect when the sample injected into the inlet <NUM> of the fine particle trap <NUM> moves along the channel <NUM>. In this case, control conditions for the electrode <NUM> and/or the heat source <NUM> may be predefined. In addition, the processor <NUM> may obtain a spectrum by repeatedly controlling the light source <NUM> and the detector <NUM> included in the measurer <NUM> one or more times when the fine particles are trapped in the plurality of through holes. The driving conditions (e.g., wavelength, intensity of current, duration, etc.) for the light source <NUM> may be predefined, and the processor <NUM> may drive the light source according to the driving conditions.

When one or more spectra are measured, the processor <NUM> may estimate the number of fine particles trapped in the plurality of through holes by analyzing the measured spectra. The processor <NUM> may extract one or more features by analyzing the spectra, and estimate the number of fine particles by applying a predefined fine particle estimation model to the extracted features. Here, the estimation model, which is a model that defines a correlation between features extracted from a spectrum and the number of fine particles, may be a linear model, a regression model, a neural network model, etc. However, embodiments are not limited thereto.

<FIG> is a diagram illustrating a change in transmission spectra before and after fine particles are trapped in the plurality of through holes. The left side of <FIG> shows through holes <NUM> before fine particles are trapped, and the right side shows through holes <NUM> after the fine particles are trapped. A spectrum <NUM> represents a transmission spectrum as measured in the through holes <NUM> before fine particles are trapped and a spectrum <NUM> represents a transmission spectrum as measured in the through holes <NUM> after the fine particles are trapped.

<FIG> illustrates a transmission spectrum <NUM> measured in the plurality of through holes and a graph <NUM> showing the change trend of transmittance according to the number of fine particles trapped in the plurality of through holes. As the fine particles are trapped in the through holes, the transmission spectrum changes and the change in transmission spectrum has a correlation with the number of the trapped fine particles. Based on this correlation, the number of the fine particles trapped in the plurality of through holes may be estimated.

The processor <NUM> may extract one or more features from the transmission spectrum measured in the plurality of through holes. For example, the processor <NUM> may extract one or more principal components as features by performing a principal component analysis (PCA) on the transmission spectrum. For example, the processor <NUM> may extract one of the first principal component and the second principal component as a feature, or extract a value obtained by combining the two principal components as a feature. However, embodiments are not limited thereto, and the feature may be extracted by using at least one of the transmission spectrum <NUM> before the fine particles are trapped and the transmission spectrum <NUM> after the fine particles are trapped. For example, a difference of the lowest point between spectrum <NUM> and spectrum <NUM>, a difference of the peak point between spectrum <NUM> and spectrum <NUM>, or a wavelength difference between valley points between spectrum <NUM> and spectrum <NUM> may be extracted as a feature.

The processor <NUM> may input the extracted feature into the fine particle estimation model and estimate an output value of the model as the number of fine particles. <FIG> shows graphs of the first principal component PC#<NUM> and the second principal component PC#<NUM> extracted from the transmission spectrum, and <FIG> shows graphs illustrating a correlation between the score of each of the principal components PC#<NUM> and PC#<NUM> and the number of fine particles. The fine particle estimation model may be model that defines a correlation between a principal component (e.g., PC#<NUM>) extracted from a transmission spectrum and the number of fine particles. Through the fine particle estimation model, the number of the fine particles trapped in the plurality of through holes may be directly quantified, thereby minimizing quantitative errors even when the chamber size is small.

The processor <NUM> may determine whether to calibrate the fine particle estimation model, and perform calibration of the fine particle estimation model when it is determined to perform calibration. In this case, conditions for performing calibration may be predefined. According to the conditions for performing calibration, calibration may be performed when there is a user's request, when a preset calibration period is reached, or before or after the fine particles are estimated. Upon determining to perform calibration, the processor <NUM> may guide the user to perform calibration, thereby preparing reference particles or the like.

When it is determined to perform calibration, reference particles may be injected through the inlet <NUM>. The reference particles may include one or more types of fine particles and a predefined number of fine particles of each type. When the reference particles are injected to the inlet <NUM>, the processor <NUM> may control the electrode <NUM> and/or the heat source <NUM> of the fine particle trap <NUM> so that the reference particles can be trapped in the plurality of through holes <NUM> of the chamber <NUM>. When the reference particles are trapped in the plurality of through holes <NUM>, the processor <NUM> may control the measurer <NUM> several times to obtain a plurality of calibration spectra in the plurality of through holes <NUM>. When the calibration spectra are obtained, one or more features may be extracted as training data from the obtained calibration spectra, and the fine particle estimation model may be trained using the extracted training data. For example, a principal component (e.g., the first or second principal component) may be extracted as training data by performing a PCA of the calibration spectra, and the fine particle estimation model that defines a correlation between the principal component and the number of fine particles may be trained based on the extracted training data.

<FIG> is a block diagram illustrating an apparatus configured to detect fine particles according to another example embodiment.

Referring to <FIG>, an apparatus <NUM> configured to detect fine particles may include a fine particle trap <NUM>, a measurer <NUM>, a processor <NUM>, an output interface <NUM>, a storage <NUM>, and a communication interface <NUM>. The measurer <NUM> includes a light source <NUM> and a detector <NUM>, and the fine particle trap <NUM>, the measurer <NUM>, and the processor <NUM> are described above, and thus detailed descriptions thereof will not be reiterated below.

The output interface <NUM> may output the processing process or processing results (e.g., the estimated number of fine particles) of the fine particle trap <NUM>, the measurer <NUM>, and the processor <NUM>. The output interface <NUM> may provide information to the user using, for example, a visual output module (e.g., display), a voice output module (e.g., speaker), a haptic module, and the like. In addition, the output interface <NUM> may output calibration guide under the control of the processor <NUM>.

The storage <NUM> may store various types of data (e.g., calibration conditions, light source control conditions, heat source control conditions, electrode control conditions, a fine particle estimation model, etc.) necessary for the fine particle trap <NUM>, the measurer <NUM>, and the processor <NUM> and/or processing results (e.g., the number of fine particles). The storage <NUM> may include at least one type of storage medium of a flash memory type, a hard disk type, a multimedia card fine type, a card type memory (for example, secure digital (SD) or extreme digital (XD) memory), a random access memory (RAM), a static random access memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM), a magnetic memory, a magnetic disk, and an optical disk.

The communication interface <NUM> may communicate with an external device to transmit and receive various data to and from the external device under the control of the processor <NUM>. The external device may be medical equipment, a printer to print out results, a display to display the results, a digital television (TV), a desktop computer, a cellular phone, a smartphone, a tablet device, a laptop computer, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation system, an MP3 player, a digital camera, a wearable device, and the like, but is not limited thereto.

The communication interface <NUM> may communicate with the external device by using various communication techniques such as Bluetooth communication, Bluetooth Low Energy (BLE) communication, Near Field Communication (NFC), WLAN communication, Zigbee communication, Infrared Data Association (IrDA) communication, wireless fidelity (Wi-Fi) Direct (WFD) communication, Ultra-Wideband (UWB) communication, Ant+ communication, Wi-Fi communication, Radio Frequency Identification (RFID) communication, <NUM> communication, <NUM> communication, <NUM> communication, and the like. However, embodiments are not limited thereto.

<FIG> is a flowchart illustrating a method of detecting fine particles according to an example embodiment.

The method illustrated in <FIG> is an example of a method of detecting fine particles performed by the apparatuses <NUM> and <NUM> configured to detect fine particles shown in <FIG> and <FIG>, which is described in detail above, and will be briefly described below.

In operation <NUM>, when a sample is injected into the inlet of the fine particle trap, the electrode and/or the heat source may be controlled to allow fine particles to be trapped in a plurality of through holes. The plurality of through holes may have a diameter of <NUM> or less to trap the fine particles, for example, superfine particles one-by-one, and the number and arrangement of the through holes and the size and shape of each through hole are not particularly limited and may vary depending on the shape, size, and type of target fine particles. The plurality of through holes are formed to penetrate in a direction perpendicular to the length direction of the channel so that the fine particles in the sample moving along the channel can be more rapidly trapped in the through holes by capillarity, dielectrophoresis, and/or photothermal effect.

In operation <NUM>, a spectrum may be obtained from the plurality of through holes by the measurer. The light source included in the measurer may be controlled to emit light to the plurality of through holes in which the fine particles are trapped, and light scattered, reflected, or transmitted through the plurality of through holes may be detected by the detector to obtain the spectrum.

In operation <NUM>, the number of the fine particles trapped in the through holes may be estimated by analyzing the measured spectrum. For example, a feature may be extracted from the spectrum by analyzing the spectrum through a PCA. In this case, the feature may be the first principal component and/or the second principal component of the spectrum.

<FIG> is a flowchart illustrating a method of detecting fine particles according to another example embodiment.

In operation <NUM>, the processor may determine whether to calibrate the fine particle estimation model. The processor may determine to calibrate the fine particle estimation model when a predetermined condition is satisfied. According to the conditions for performing calibration, calibration may be performed when there is a user's request, when a preset calibration period is reached, or before or after the fine particles are estimated.

In operation <NUM>, reference particles may be injected into the inlet of the fine particle trap. Here, the reference particles may include a preset type and preset number of fine particles, and there may be one or more types of the reference particles.

Then, the reference particles injected into the inlet of the fine particle trap move along the channel and are trapped in the plurality of through holes by capillarity, dielectrophoresis, and/or photothermal effect. In this case, the processor may control the electrode and/or the heat source to induce the dielectrophoresis and/or photothermal effect.

In operation <NUM>, a plurality of calibration spectra may be measured through the light source and detector included in the measurer.

In operation <NUM>, the fine particle estimation model may be trained based on the plurality of calibration spectra. For example, a plurality of principal components may be extracted as training data by performing a PCA of the plurality of calibration spectra, and the fine particle estimation model may be trained based on the extracted training data.

The present disclosure may be realized as a computer-readable code written on a computer-readable recording medium. The computer-readable recording medium may be any type of recording device in which data is stored in a computer-readable manner.

Examples of the computer-readable recording medium include a read-only memory (ROM), a random-access memory (RAM), a compact disc (CD)-ROM, a magnetic tape, a floppy disc, an optical data storage, and a carrier wave (e.g., data transmission through the Internet). The computer-readable recording medium may be distributed over a plurality of computer systems connected to a network so that a computer-readable code is written thereto and executed therefrom in a decentralized manner. Functional programs, codes, and code segments for implementing the disclosure be easily deduced by computer programmers of ordinary skill in the art, to which the disclosure pertains.

Claim 1:
An apparatus configured to detect fine particles, comprising:
a fine particle trap comprising a plurality of through holes that are configured to trap the fine particles;
a measurer comprising:
a light source configured to emit light to the plurality of through holes, wherein the plurality of through holes have a diameter equal to or less than <NUM>, and
a detector configured to detect light scattered, reflected, or transmitted through the plurality of through holes and measure a spectrum; and
a processor configured to estimate a number of the fine particles trapped in the plurality of through holes based on of the measured spectrum,
characterised in that the processor is configured to extract one or more features from the spectrum using a principal component analysis, PCA, and estimate the number of the fine particles based on the extracted features using a fine particle estimation model, wherein the fine particle estimation model defines a correlation between an extracted principal component and the number of fine particles.