KR20240123469A - Method for Irradiating Linear Laser, Device for Irradiating Linear Laser and Device for Analyzing Large Area Comprising Same - Google Patents

Abstract

The present invention relates to a linear laser irradiation method using a galvanometer mirror, a linear laser irradiation device, and a large-area analysis device including the same. According to the present invention, a linear laser optical system can be implemented using a galvanometer and a cylindrical lens, and by using the linear laser to irradiate an analyte, and by focusing the spectral signals generated at each location through the interaction between the analyte and the linear laser beam on a large-area image sensor, spectral information according to each location can be obtained at a very high speed with a single measurement. Therefore, when the large-area analysis device using the linear laser optical system of the present invention is used, various spectroscopy methods such as Raman, fluorescence, and absorption can be applied to quickly and accurately non-destructively analyze very small-sized substances existing in large-area analysis materials such as environmental samples, biological tissues, foods, and pharmaceuticals.

Description

Method for Irradiating Linear Laser, Device for Irradiating Linear Laser and Device for Analyzing Large Area Comprising Same

The present invention relates to a linear laser irradiation method, a linear laser irradiation device, and a large-area analysis device including the same, and more specifically, to a method for irradiating a linear laser using an optical system including a galvano mirror and a cylindrical lens, a laser irradiation device having a linear laser optical system implemented, and a high-speed large-area analysis device including the same.

Plastics are widely used in various industries due to their characteristics such as low production cost, versatility, light weight, and durability. A significant portion of plastics remains in the environment due to their production, industrial and household use, and disposal in the form of waste after processing or use. Plastics discharged on land reach the ocean through rivers, streams, and other routes, and in the process, they are decomposed into microplastics by biological, optical, and mechanical factors.

These microplastics are hardly biodegradable in the natural environment, so they remain in the environment for a long time, and they can easily enter the cells of living organisms, which can affect the human immune system and cell health. Accordingly, various methods are being developed to analyze and detect microplastics.

In this regard, the literature [Q. Qui et al., Estuarine, Coastal and Shelf Science , 2016] describes a method for extracting microplastics from marine samples and then analyzing and detecting them using an optical microscope with a hyperspectral imaging technique. This optical microscopy analysis method can directly analyze microplastics from samples, so it can analyze and detect a large amount of microplastics at low cost and in a short time. However, it has limitations in accuracy due to optical characteristics such as low resolution.

Accordingly, recently, technologies for quantitative and qualitative analysis of microplastics using spectroscopy with better resolution than microscopic analysis have also been actively developed. In this regard, Korean Patent Publication No. 10-2022-0093623 describes a microplastic quantitative analysis system and its operating method that can minimize quantitative analysis errors caused by changes in the measurement environment and measurement conditions of the measuring device using near-infrared spectroscopy. However, this microplastic analysis technology using spectroscopy has a limitation in that the measurement time becomes very long depending on the number of measurement points, making it unsuitable for large-area analysis.

Therefore, in order to quickly and accurately analyze and detect microplastics present in large-area samples, it is necessary to develop a new type of analysis technique that can solve the problems of existing microscopic analysis methods and spectroscopy methods.

Under these circumstances, the inventors of the present invention developed a high-speed, large-area analysis device capable of accurately analyzing very small-sized substances existing over a wide area at a high speed by implementing a linear laser optical system using a galvano-mirror and a cylindrical lens, and completed the present invention.

An object of the present invention is to provide a linear laser irradiation device that irradiates a linear laser beam using an optical system including a galvano mirror and a cylindrical lens.

Another object of the present invention is to provide a linear laser irradiation method that irradiates a linear laser beam using an optical system including a galvano mirror and a cylindrical lens.

Another object of the present invention is to provide a large-area analysis device including the laser irradiation device.

In order to achieve the above-described purpose, the present invention provides a linear laser irradiation method, including the steps of generating a laser beam from a light source unit; the step of first linearizing the laser beam generated by the light source unit using a galvano mirror; and the step of second linearizing the laser beam linearized by the galvano mirror using a cylindrical lens.

In the present invention, the wavelength range of the laser beam may be infrared, visible light, ultraviolet or X-ray.

In the present invention, the rotation angle of the galvano mirror can be 10 to 30°.

In the present invention, the frequency of the galvano mirror can be 100 to 250 Hz.

In the present invention, the waveform of the galvano mirror may be a square wave.

The present invention also provides a linear laser irradiation device including a light source unit that generates a laser beam; a galvano mirror that first linearizes the laser beam generated from the light source unit; and a cylindrical lens that second linearizes the laser beam reflected by the galvano mirror.

The device of the present invention may further include one or more mirrors for guiding a laser beam generated from the light source unit to an incident portion of the galvano mirror.

The device of the present invention may further include one or more filters provided on the path of the laser beam between the light source unit and the galvano mirror.

The present invention also provides a large-area analysis device including the linear laser irradiation device and at least one of a spectrometer and an image sensor for detecting a spectral signal.

In the present invention, the spectrometer may be at least one selected from the group consisting of a prism spectrometer, a diffraction grating spectrometer, an interference spectrometer, and a filter spectrometer.

In the present invention, the image sensor may be a CCD (charge coupled device), an EMCCD (electron multiplying charge coupled device), an ICCD (intensified charge coupled device), or a CMOS (complementary metal-oxide semiconductor).

The large-area analysis device of the present invention may further include one or more lenses for amplifying or reducing the laser beam, and the diameter of the lenses may be 1 to 10 inches.

In the present invention, the scan speed of the large-area analysis device can be 3 to 20 mm ² /min.

In the present invention, the large-area analysis device may be used for analyzing trace substances present in environmental samples, biological tissues, foods, or pharmaceuticals.

In the present invention, the size of the fine material may be 0.1 μm to 1 mm.

The large-area analysis device of the present invention may further include a camera module for obtaining a photographed image of the analysis area.

The present invention also provides a method for reconstructing a hyperspectral image, including the steps of: obtaining a photographed image of an analysis area; extracting a spatial image of a target micro-substance for analysis from the photographed image to generate a masking image; obtaining a hyperspectral image of the analysis area using the large-area analysis device; and applying the masking image to the hyperspectral image to reconstruct the hyperspectral image.

In the present invention, the photographed image may be an RGB image.

In the present invention, the masking image generation step can be performed by removing the white background of the photographed image.

According to the present invention, a linear laser optical system can be implemented using a galvanometer and a cylindrical lens, and by using the linear laser to irradiate an analyte, and by focusing the spectral signals generated at each location through the interaction between the analyte and the linear laser beam on a large-area image sensor, spectral information according to each location can be obtained at a very high speed with a single measurement. Therefore, when a large-area analysis device using the linear laser optical system of the present invention is used, various spectroscopy methods such as Raman, fluorescence, and absorption can be applied to quickly and accurately non-destructively analyze very small-sized substances existing in large-area analytes such as environmental samples, biological tissues, foods, and pharmaceuticals.

FIG. 1 is a conceptual diagram of an analysis device including a linear laser optical system in the form of a microscope according to one embodiment of the present invention.
FIG. 2 is a photograph of an analysis device including a linear laser optical system in the form of a microscope according to one embodiment of the present invention.
FIG. 3 shows the results of analyzing polystyrene of a uniform shape using an analysis device including a linear laser optical system in the form of a microscope according to one embodiment of the present invention.
FIG. 4 shows the results of analyzing polyethylene of a non-uniform shape using an analysis device including a linear laser optical system in the form of a microscope according to one embodiment of the present invention.
FIG. 5 illustrates a MATLAB code for extracting a masking image representing spatial coordinate values from a photographed image according to one embodiment of the present invention.
FIG. 6 illustrates the result of extracting a masking image representing spatial coordinate values from a photographed image according to one embodiment of the present invention.
Figure 7 shows hyperspectral images before and after applying a masking image according to one embodiment of the present invention.
Figure 8 is a conceptual diagram of a large-area analysis device according to one embodiment of the present invention.
Figure 9 is a photograph of a large-area analysis device according to one embodiment of the present invention.
Figure 10 shows the results of analyzing microplastics using a large-area analysis device according to one embodiment of the present invention.
FIG. 11 shows the results of measuring sensitivity when a constant light source is input to a high-sensitivity EMCCD (electron multiplying charge coupled device) detector according to one embodiment of the present invention.
Figure 12(a) shows the sensitivity measured using square wave laser beams of various frequencies in a large-area analysis device according to one embodiment of the present invention.
Figure 12(b) shows the sensitivity measured using sine wave laser beams of various frequencies in a large-area analysis device according to one embodiment of the present invention.
Figure 12(c) shows the sensitivity measured using a triangle wave laser beam of various frequencies in a large-area analysis device according to one embodiment of the present invention.
Figure 12(d) shows the sensitivity measured using sawtooth laser beams of various frequencies in a large-area analysis device according to one embodiment of the present invention.

Hereinafter, specific implementation forms of the present invention will be described in more detail. Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by a person skilled in the art to which the present invention belongs. In general, the nomenclature used in this specification is well known and commonly used in the art.

The present invention relates to a laser irradiation method and a laser irradiation device that irradiates a linear laser beam using an optical system including a galvano mirror and a cylindrical lens.

According to the present invention, by using an optical system including a galvano mirror and a cylindrical lens to perform linear laser irradiation, a large amount of spectral information according to each location of an analyte can be obtained with a single measurement, thereby enabling physicochemical analysis at a much faster speed than general mapping analysis, and allowing a large number of samples to be measured simultaneously and quickly.

Conventional microscopic analysis methods have the problem that it is difficult to identify the type and components of very small substances at the microscopic level due to optical characteristics such as low resolution, and in the case of analysis using spectroscopy, there is a problem that the measurement time becomes very long depending on the number of measurement points of the analyte, so there is a limitation that it is not suitable for large-area analysis.

The present invention is to overcome the limitations of analysis using such microscopic analysis and spectroscopy, and by irradiating a linear laser on an analyte using a laser irradiation device including a galvano mirror and a cylindrical lens, spectral information according to each position of the entire spatial area of the target can be measured at a very high speed, and various spectroscopy methods such as Raman, fluorescence, and absorption can be applied, so that quantitative and qualitative information of the analysis target can be non-destructively analyzed by applying an appropriate spectroscopy method depending on the analysis target and purpose.

Specifically, the laser irradiation device of the present invention includes a light source unit that generates a laser beam; a galvano mirror that first linearizes the laser beam generated from the light source unit; and a cylindrical lens that second linearizes the laser beam reflected by the galvano mirror.

According to the present invention, by simultaneously utilizing the first linearization using a galvano mirror and the second linearization using a cylindrical lens, a linear laser having a narrow linewidth and very uniform energy distribution can be irradiated. In particular, since the distribution of the spectral signal can be uniformly adjusted at the detection end, high-sensitivity detection performance can be exhibited.

As the above light source unit, a laser generator capable of generating a laser beam of an appropriate wavelength according to the spectroscopy to be applied to the linear laser optical system can be used, and for example, a continuous wave laser generator or a pulse laser generator can be used.

Specifically, as the continuous wave laser generator, an Ar laser, a Kr laser, a CO ₂ laser, a YAG laser, a YVO ₄ laser, a YLF laser, a YAlO ₃ laser, a GdVO ₄ laser, a Y ₂ O ₃ laser, a ruby laser, an alexandrite laser, a titanium sapphire laser, a helium-cadmium laser, a GaN laser, a GaAs laser, or an InAs laser can be used, and as the pulse laser generator, an Ar laser, a Kr laser, an excimer laser, a CO ₂ laser, a YAG laser, a YVO ₄ laser, a YLF laser, a YAlO ₃ laser, a GdVO ₄ laser, a Y ₂ O ₃ laser, a glass laser, a ruby laser, an alexandrite laser, a titanium sapphire laser, a GaN laser, a GaAs laser, an InAs laser, a copper vapor laser, a gold vapor laser, or the like can be used.

The wavelength range of the above laser beam can be infrared, visible light, ultraviolet or X-ray, and a laser beam of an appropriate wavelength can be selected and used depending on the spectroscopy to be applied to the linear laser optical system. For example, when applying Raman spectroscopy, if a laser beam in the near infrared region with a wavelength of 1,064 nm or the ultraviolet region with a wavelength of 270 nm or less is used, fluorescence interference is reduced or the fluorescence region is separated and generated outside the Raman spectrum region, so that spectrum measurement by pure Raman scattering can be facilitated.

In the present invention, the galvanometer mirror means a mirror to which a galvanometer motor is attached.

The above galvanometer motor can convert a laser beam reflected by a galvanometer mirror into a linear beam by changing the inclination angle of the galvanometer mirror according to the voltage applied.

Specifically, the galvanometer mirror changes the scanning direction of the laser beam, thereby enabling multi-point, i.e. linear, laser scanning with a single laser beam.

For example, to check n modes, a step function of n+1 is generated and input to the galvanometer motor and when it is rotated at a constant frequency, the galvanometer mirror moves in the order of 1, 2, ..., n+1. When a laser beam is incident on the moving galvanometer mirror, the laser beam reflected by the galvanometer moves to the desired scan location, linearly scanning the sample and acquiring data. Due to the characteristic of the step function, the mirror rotates and then stops for a moment, and data at the corresponding position is acquired. After repeating the above process and separating the data at the same position, time-domain data at the corresponding position can be acquired, and at this time, a constant rotation frequency of the galvanometer mirror becomes the measurement frequency of the separated time-domain data.

The present invention adjusts the energy distribution of a laser beam uniformly and improves the linearity of the laser beam by controlling the conditions of the rotation angle, frequency, waveform, etc. of the galvano mirror, thereby obtaining a uniform and clean processed part.

Specifically, the rotation angle of the galvanometer mirror may be 10 to 30°, preferably 15 to 25°, and more preferably 17 to 22°. If the rotation angle is smaller than the above range, the size of the laser beam is too small, which is not preferable, and if it is larger than the above range, energy loss of the laser beam may occur, which is not preferable.

The frequency of the above galvano mirror may be 100 to 250 Hz, preferably 170 to 230 Hz, and more preferably 190 to 210 Hz. If the frequency is out of the above range, the energy distribution of the laser beam is not uniform, so that the shape of the laser beam may be different at the center and periphery of the scan area, thereby reducing the linearity of the laser beam, which is not preferable.

The waveform of the laser beam formed by the above galvano mirror can be various waveforms such as a square wave, a sine wave, a triangle wave, a sawtooth wave, etc., but in order to uniformly control the laser beam in the same shape throughout the scan area, a square wave is preferable.

In one embodiment of the present invention, through a linearity experiment according to the waveform and frequency of the laser beam, it was confirmed that the linearity of the laser beam was the best when the control signal wave of the galvano mirror was a square wave with a rotation angle of 20° and a frequency of 200 Hz.

In the present invention, the cylindrical lens may mean a cylindrical lens having a convex surface on the incident or emission side, or having convex surfaces on both sides, and in terms of low aberration and accuracy, it is preferable to use a cylindrical lens having a convex surface on the incident surface.

The above cylindrical lens can generate a linear laser beam by transmitting a parallel laser beam incident on the cylindrical lens and then linearizing the laser beam in the horizontal direction.

Conventional linear laser beam irradiation systems could increase the scanning speed by converting a spot-focused laser beam into a line-focused laser beam, but had the limitation that the spatial resolution significantly decreased as the laser beam was linearized. In the present invention, by using a galvano-mirror and a cylindrical lens together in a linear optical system, a laser beam with a longer and narrower linewidth can be irradiated, and at the same time, by controlling the waveform, frequency, rotation angle, etc. of the galvano-mirror, the energy distribution of the laser beam can be uniformly adjusted, thereby obtaining a hyperspectral image with a higher resolution over the entire scan area.

In addition, in one embodiment of the present invention, the energy distribution of the laser beam detected at the detection unit can be more uniformly adjusted through the galvanometer control software.

The linear laser irradiation device of the present invention may further include a filter and a mirror that transmit or reflect the laser beam. Specifically, the filter and the mirror are positioned between the laser beam generated from the light source unit and the galvano mirror, and can adjust the wavelength, direction of travel, etc. of the generated laser beam, and can guide the laser beam to be introduced into the incident portion of the galvano mirror.

In the present invention, a laser beam is generated from a light source, the laser beam generated by the light source is primarily converted into a linear laser beam using a galvano mirror, and the linear laser beam reflected by the galvano mirror is secondarily linearized using a cylindrical lens, thereby generating a linear laser beam having a longer and more uniform energy distribution, thereby enabling much more precise and faster laser scanning.

When the above laser irradiation method is used, a large number of spectral signals can be obtained in a single measurement by irradiating a linear laser beam on the analyte, making it easy to analyze a large area of a sample and measure a large number of samples simultaneously.

The present invention also provides a large-area analysis device including the laser irradiation device. The large-area analysis device of the present invention can be applied to fields requiring analysis of very small-sized substances within a large-area sample.

The large-area analysis device of the present invention may further include mirrors, lenses, and filters that reflect or transmit, or amplify or reduce, a laser beam for high resolution and accuracy. Specifically, the mirrors may further include a dielectric mirror, a chromatic mirror, or the like, the lenses may further include an isometric lens, a flat lens, or the like, and the filters may further include a band-pass filter, a long-pass filter, or the like.

The above mirrors, lenses, and filters can be selected to have appropriate apertures depending on the analysis target and purpose. For example, when measuring a large area of analyte or measuring a large amount of analytes simultaneously, it is preferable that the mirrors, lenses, and filters have apertures of 1 to 10 inches.

The large-area analysis device of the present invention may also include one or more of a spectrometer and an image sensor for detecting a spectral signal.

The above spectrometer can be used to disperse a laser beam of an appropriate wavelength according to the applicable spectroscopy method, taking into account spectral resolution. For example, a prism spectrometer using a prism, a diffraction grating spectrometer using a diffraction grating, an interference spectrometer using interference of light, a filter spectrometer using a filter, a spectrometer using a combination of a prism and a diffraction grating, etc. can be used.

The above image sensor can be used to detect a specific range of wavelengths of a dispersed laser beam depending on the spectroscopy to be applied, taking into consideration sensitivity, resolution, etc., and for example, a CCD (charge coupled device), an EMCCD (electron multiplying charge coupled device), an ICCD (intensified charge coupled device), or a CMOS (complementary metal-oxide semiconductor) can be used. In terms of obtaining a high-resolution hyperspectral image, it is preferable to use an EMCCD (electron multiplying charge coupled device).

By detecting a spectral signal generated by the interaction between a laser beam and an analyte using the above spectrometer and image sensor, a highly reliable hyperspectral image of the analyte can be obtained in a short period of time.

The large-area analysis device of the present invention can quickly obtain a high-resolution hyperspectral image by scanning a large-area sample of the mm ² level or more at a very high speed. Specifically, the scan speed of the large-area analysis device can be 3 to 20 mm ² /min, preferably 5 to 15 mm ² /min, and more preferably 8 to 12 mm ² /min.

In one embodiment of the present invention, it was confirmed that the chemical structure and components of particles in a sample can be predicted through Raman spectra at each location through hyperspectral images acquired through the spectrometer and image sensor, and the types of particles in the sample can be distinguished with 99.7% accuracy through machine learning. In addition, it was confirmed that large-area analysis is possible at a very high speed, as it took about 12 minutes to acquire about 1.05 million spectra in a range of 9 mm x 9 mm.

In the present invention, the large-area analysis device may further include a camera module. Hyperspectral images have a problem in that signals spread on the image when the detected signal is strong, but in the present invention, by extracting a masking image from an image captured using a camera module and applying it to a hyperspectral image, the accuracy of location information can be increased and a clean and clear hyperspectral image can be obtained without signal spreading.

Specifically, in order to reconstruct a hyperspectral image, a method including the steps of: obtaining a photographed image of an analysis area; extracting a spatial image of a fine material to be analyzed from the photographed image to generate a masking image; obtaining a hyperspectral image of the analysis area using the large-area analysis device of the present invention; and applying the masking image to the hyperspectral image to reconstruct the hyperspectral image can be used to obtain a high-resolution hyperspectral image containing accurate locational spatial information.

For example, the above-described captured image may be an 8-bit RGB image. The captured image, which is an 8-bit RGB image, has values for each element of red (R), green (G), and blue (B), and the closer the sum of the corresponding values gets to 765 (255 + 255 + 255), the whiter it becomes. By combining all the RGB values of the captured image and then using Matlab code to apply a specific threshold to the obtained data to remove all white backgrounds, leaving only the image of the area where the fine material to be detected exists, and using this as spatial coordinates to perform image processing, a masking image containing the exact location and spatial information of the fine material to be detected can be generated.

The large-area analysis device of the present invention not only enables physicochemical analysis of a wide area, but also exhibits high resolution and accuracy, so it can be applied to fields requiring precise analysis and can be easily used to detect and analyze very small-sized micro-substances at a high speed.

Specifically, the large-area analysis device of the present invention can be used to non-destructively analyze trace substances present in environmental samples, biological tissues, foods, or pharmaceuticals.

For example, the large-area analysis device of the present invention can be used in the medical field to detect biological tissues such as cancer tissues.

Conventional methods for detecting cancer cells, such as intraoperative frozen area analysis, radiography, and use of contrast agents, have the problems of high cost and time consumption, but when the large-area analysis device of the present invention is used, hyperspectral images showing information on the physiology, morphology, and composition of biological tissues such as cancer cells can be quickly obtained, and various biological signals such as hypervascularity, abnormal neovascularization, mutation of malformed blood vessels, damage to neovascular vessels, noninvasive intravascular oxygen saturation, oxygen movement between blood vessels, and verification of vascular treatment effects can be quickly and accurately analyzed.

The size of fine substances that can be detected by the large-area analysis device of the present invention can be controlled according to the spectroscopy applied to the large-area analysis device, and can be, for example, 0.1 μm to 1 mm. Specifically, when Raman spectroscopy is applied to the large-area analysis device, fine substances with a size of 1 to 100 μm can be analyzed and detected with high accuracy.

Accordingly, when the large-area analysis device of the present invention is used, in various fields such as environment, medicine, food, industry, and agriculture, it is possible to quickly and accurately analyze very small-sized substances existing in a large-area analyte through application of various spectroscopic methods.

Example

The present invention will be described in more detail through the following examples. However, these examples are provided to illustrate some experimental methods and configurations in order to exemplify the present invention, and the scope of the present invention is not limited to these examples.

Experimental Example 1: Analysis of microplastics using an analysis device including a linear optical system

A microscope system and a CCD (charge coupled device) detector were introduced into a linear optical system including a 2D galvanometer and a cylindrical lens, and a galvanometer control software that uniformly adjusts the distribution of spectral signals detected by the detector was applied to implement an analysis device capable of obtaining uniform hyperspectral images. The conceptual diagram and photograph thereof are shown in Figures 1 and 2, respectively.

Specifically, the size of the linear laser beam irradiated on the sample at a 10x objective lens was 450 μm x 10 μm, which implemented a beam with a very small linewidth, and the laser energy distribution through the 2D galvanometer showed a uniform laser beam distribution with a relative standard deviation of 8.4%. A lens optical system was built between the image plane and the CCD detector and designed with a magnification of 2.5x, and the resolution of the spatial distribution was 0.92 μm, which showed excellent resolution as a result of calculation using the USAF resolution standard.

Raman spectroscopy was applied to the above-mentioned analysis device to analyze microplastics. At this time, as the analytes, a sample composed of polystyrene having uniform spherical particles with a diameter of about 100 μm as a standard material and a sample composed of polyethylene having non-uniform particles with a diameter of about 100 μm similar to those collected from the environment were used, and the results of analyzing the above-mentioned samples are shown in Figures 3 and 4, respectively.

Referring to Figs. 3 and 4, the results of implementing the peaks of the Raman spectra obtained by analyzing each sample into images match well with the images observed under a microscope, and it was confirmed that the chemical structure and components of microplastics can be predicted through the Raman spectra at each image location. In addition, it was found that analysis was possible at a very fast speed, as it took about 20 minutes to acquire about 160,000 spectra in the range of 368 μm x 1000 μm.

Experimental Example 2: Hyperspectral Image Generation Using Masking Images

In order to solve the spreading problem caused by the strong Raman signal in the acquired hyperspectral image and obtain an image representing accurate spatial information, a MATLAB code such as that in Fig. 5 was used to extract a masking image representing spatial coordinate values from the captured image, as in Fig. 6, and this was then applied to the acquired hyperspectral image.

Hyperspectral images before and after applying the masking image are shown in Fig. 7, and through Fig. 7, it was confirmed that a hyperspectral image showing accurate spatial information without signal spreading phenomenon can be obtained by applying the masking image.

Experimental Example 3: Microplastic Analysis Using a Large-Area Analysis Device

In order to simultaneously analyze a wider range of areas than the analysis device of Experimental Example 1, a 2-inch large-diameter lens and a high-sensitivity EMCCD (electron multiplying charge coupled device) detector were introduced into a linear optical system including a galvanometer and a cylindrical lens, thereby implementing a large-area analysis device capable of acquiring large-area hyperspectral images, the conceptual diagram and photograph of which are shown in FIGS. 8 and 9, respectively.

Raman spectroscopy was applied to the above large-area linear optical system to analyze microplastics. At this time, samples composed of polystyrene, polyethylene, polypropylene, polymethacrylate, polyvinyl chloride, polyvinyl alcohol, sea sand, and dust were used as analytes, and the results of analyzing the samples are shown in Fig. 10.

The left image of Fig. 10 is a photographed image of the sample, and the right image is a hyperspectral image to which a masking image has been applied using the method of Experimental Example 1. Through Fig. 10, it was confirmed that the chemical structure and components of the particles in the sample can be predicted through the Raman spectrum at each image location, and the types of particles in the sample can be distinguished with 99.7% accuracy through machine learning. In addition, it was found that large-area analysis is possible at a very fast speed, as it took about 12 minutes to acquire 1,048,576 spectra in a range of 9 mm x 9 mm.

Experimental Example 4: Linearity Experiment According to Waveform and Frequency of Galvano Mirror

In order to judge the linearity of the laser beam according to the waveform and frequency of the galvano mirror, the sensitivity was measured when a constant light source was input to a high-sensitivity EMCCD (electron multiplying charge coupled device) detector (Fig. 11), and the sensitivity was measured using the same light source, but by fixing the rotation angle of the laser beam to 2 and changing the waveform and frequency using the large-area analysis device of Experimental Example 2 (Figs. 12(a) to 12(d)).

The sensitivity measured under the waveform conditions of Fig. 12(a) for a square wave, Fig. 12(b) for a sine wave, Fig. 12(c) for a triangle wave, and Fig. 12(d) for a sawtooth wave at frequencies of 100, 150, 200, and 250 Hz, respectively, is shown.

Referring to Fig. 12, the result of measuring the sensitivity under the conditions of a square wave and a 200 Hz galvano-mirror (Fig. 12(a)) was most similar to the result of measuring the sensitivity when a constant light source was supplied to the detector (Fig. 11) in terms of the comprehensive aspects of linearity, mean, and standard deviation (std). Through this, it was found that when a galvano-mirror with a rotation angle of 20°, a frequency of 200 Hz, and a square wave was used, the wavelength shape most similar to the graph of Fig. 11 was exhibited, indicating that the linearity of the laser beam was the best.

From the above description, those skilled in the art will understand that the present invention can be implemented in other specific forms without changing the technical idea or essential characteristics thereof. In this regard, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. The scope of the present invention should be interpreted as including all changes or modifications derived from the meaning and scope of the patent claims described below rather than the above detailed description and their equivalent concepts within the scope of the present invention.

Claims (20)

A step of generating a laser beam from a light source;
A step of first linearizing the laser beam using a galvano mirror; and
A step of linearizing a laser beam linearized first by the galvano mirror by a second linearization using a cylindrical lens.
A linear laser irradiation method comprising: In paragraph 1,
A linear laser irradiation method, wherein the wavelength range of the laser beam is infrared, visible light, ultraviolet or X-ray. In paragraph 1,
A linear laser irradiation method, wherein the rotation angle of the galvano mirror is 10 to 30°. In paragraph 1,
A linear laser irradiation method, wherein the frequency of the galvano mirror is 100 to 250 Hz. In paragraph 1,
A linear laser irradiation method in which the waveform of the galvanometer mirror is a square wave. A light source that generates a laser beam;
A galvanometer mirror that linearizes the laser beam generated from the light source; and
A cylindrical lens that linearizes the laser beam reflected by the above galvano mirror.
A linear laser irradiation device comprising: In paragraph 6,
A linear laser irradiation device further comprising one or more mirrors for guiding a laser beam generated from the light source unit to an incident portion of the galvano mirror. In paragraph 6,
A linear laser irradiation device further comprising one or more filters provided on the path of the laser beam between the light source unit and the galvano mirror. A linear laser irradiation device according to any one of claims 6 to 8; and
One or more of a spectrometer and an image sensor for detecting a spectral signal
A large-area analysis device including: In Article 9,
A large-area analysis device, wherein the spectrometer is at least one selected from the group consisting of a prism spectrometer, a diffraction grating spectrometer, an interference spectrometer, and a filter spectrometer. In Article 9,
A large-area analysis device wherein the image sensor is a CCD (charge coupled device), an EMCCD (electron multiplying charge coupled device), an ICCD (intensified charge coupled device), or a CMOS (complementary metal-oxide semiconductor). In Article 9,
A large-area analysis device further comprising one or more lenses for amplifying or reducing the laser beam. In Article 12,
A large-area analysis device having a lens diameter of 1 to 10 inches. In Article 9,
A large-area analysis device having a scan speed of 3 to 20 mm ² /min. In Article 9,
A large-area analysis device, wherein the analysis target of the above large-area analysis device is a microscopic substance existing in an environmental sample, a biological tissue, a food, or a pharmaceutical. In Article 15,
A large-area analysis device, wherein the size of the above fine material is 0.1 μm to 1 mm. In Article 9,
A large-area analysis device further comprising a camera module for obtaining a photographed image of the analysis area. Step of obtaining a photographed image of the analysis area;
A step of extracting a spatial image of a micro-substance to be analyzed from the above-mentioned photographed image and generating a masking image;
A step of obtaining a hyperspectral image of an analysis area using a large-area analysis device of Article 9; and
A step of reconstructing a hyperspectral image by applying a masking image to the above hyperspectral image.
A method for reconstructing a hyperspectral image, comprising: In Article 18,
A method for reconstructing a hyperspectral image, wherein the above-mentioned photographed image is an RGB image. In Article 18,
A method for reconstructing a hyperspectral image, wherein the above masking image generation step is performed by removing a white background of a photographed image.