KR20200102279A - Laser desorption ionization apparatus with co-axial laser-vision - Google Patents

Abstract

The present invention relates to a mass spectrometer for a sample. According to one embodiment of the present invention, the mass spectrometer may comprise: a laser irradiating a laser to a sample; a camera photographing the sample; and a laser irradiation unit including a dichroic mirror passing one among light of the laser and visible light reflected from a surface of a pixel, and reflecting the other one.

Description

Laser Vision Coaxial LDI Device {LASER DESORPTION IONIZATION APPARATUS WITH CO-AXIAL LASER-VISION}

It is related to Laser Desorption Ionization. More specifically, it relates to an apparatus for analyzing a sample by a laser desorption ionization method.

Conventionally, there is a system in which a vision system and a laser operate separately to analyze a sample. However, when the position of the sample is changed or the irradiation position of the laser is changed, there is a problem that the focus of the vision system is not properly adjusted.

Therefore, there is a need to develop a device capable of analyzing various samples without limitation by moving the vision system of the sample and the laser system coaxially.

US Patent Publication No. US 2017/0358438 A1 (published on December 14, 2017) discloses a single particle inductively coupled plasma mass spectrometer. The invention relates to a system for analyzing the mass spectrum of a display.

According to an embodiment, an apparatus for analyzing a sample by a laser desorption ionization method, comprising: a laser irradiator; And an ion detector detecting ions desorbed from the sample, wherein the laser irradiation unit comprises: a laser irradiating laser light to the sample; A camera for photographing the sample; And a dichroic mirror that passes one of the laser light and visible light reflected from the pixel surface and reflects the other.

According to another embodiment, the dichroic mirror also discloses a mass spectrometry device in which an optical path emitted from the laser and irradiated to a sample coincides with an optical path of the camera.

According to another embodiment, the laser may be fixed to the camera and the dichroic mirror to move together.

According to another embodiment, the laser irradiation unit may include a lens disposed in a path through which the laser light is emitted; And a chromatic aberration filter for correcting chromatic aberration generated by the lens is also disclosed.

According to another embodiment, a mass spectrometry apparatus further comprising an aspherical mirror reflecting laser light passing through the dichroic mirror to the sample and reflecting visible light reflected from the sample to the dichroic mirror is provided. do.

According to another embodiment, the aspherical mirror may further include a hole having a predetermined size or less so that ions desorbed from the sample pass through.

According to an embodiment, the ion detector is provided with a mass spectrometry device that detects ions emitted in a direction substantially perpendicular to the sample surface by irradiation with the laser.

According to another embodiment, a plate on which the sample is placed; And a plate cover surrounding the plate and the sample and fixed at the same position inside the mass spectrometer regardless of the thickness of the sample.

According to one side, there is provided a coaxial laser used in a mass spectrometry apparatus for a sample, comprising: a laser for irradiating laser light onto the sample; A camera for photographing the sample; And a dichroic mirror that passes one of the light of the laser and the visible light reflected from the surface of the pixel and reflects the other.

According to the other side, the dichroic mirror is provided with a coaxial laser that allows the optical path emitted from the laser to be irradiated to the sample and the optical path of the camera to match.

According to another aspect, the laser may be fixed to the camera and the dichroic mirror to move together.

According to the other side, a lens disposed in a path through which the light of the laser is emitted; And a chromatic aberration filter for correcting chromatic aberration generated by the lens.

In addition, the laser may be a coaxial laser that emits light having a wavelength of 343 nm or more and 355 nm or less.

1 shows a structure of a mass spectrometer according to an embodiment.
2 shows a structure of a coaxial laser according to an embodiment.
3 shows a structure of another coaxial laser according to an embodiment.
4 shows a laser irradiation unit mounted on a mass spectrometer according to an embodiment.
5 shows a state in which two types of samples are placed on a plate according to an embodiment.
6 shows a plate cover and a sample according to an embodiment.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, the scope of the rights is not limited or limited by these embodiments. The same reference numerals in each drawing indicate the same members.

The terms used in the description below have been selected as general and universal in the related technical field, but there may be other terms depending on the development and/or change of technology, customs, preferences of technicians, and the like. Therefore, terms used in the following description should not be understood as limiting the technical idea, but should be understood as exemplary terms for describing embodiments.

In addition, in certain cases, there are terms arbitrarily selected by the applicant, and in this case, detailed meanings will be described in the corresponding description. Therefore, terms used in the following description should be understood based on the meaning of the term and the contents throughout the specification, not just the name of the term.

1 is a diagram showing the overall structure of a mass spectrometer according to an embodiment. The mass spectrometry apparatus 100 according to an embodiment may include an ion detector 110, a laser 120, and a camera 130. In addition, it may further include a plate 150 on which the sample 140 is disposed.

According to an embodiment, the mass spectrometer may analyze a sample by laser desorption ionization. The mass spectrometer can measure a sample in a high vacuum condition. To this end, the chamber may further include a sample introduction unit and a vacuum system. The sample may go through a low vacuum condition to enter a high vacuum condition from the atmospheric condition.

The laser 120 may irradiate laser light onto the sample. The laser irradiation unit 120 may include a micro-focus laser optical system of 5 μm or less. The laser irradiation unit 120 may analyze a sample of a very small size, and for example, but not limited to, a high-resolution OLED (Organic Light Emitting Diode) panel having a QHD level or higher may also be directly analyzed in pixel units. The sample is not limited to an OLED sample, and a microbial sample used in MLADI is also possible. Through this, it is possible to analyze a unit smaller than 100 ~ 200um, which is a laser beam size generally used in MALDI-TOF, and a higher resolution can be achieved.

The ion detector 130 may detect ions desorbed from the sample. The ion detector 130 may use an ion optical system. The ion optical system may transfer ions to the ion detector 110 using a high voltage or high voltage pulse. The ion optical system may include ion deflectors. The ion deflector can perform a function of correcting the path of ions and sending them in a desired direction. The ion optical system may include a lens. The lens may serve to collect the spreading ions to the ion detector 130.

The desorbed ions pass through a flight tube to reach the ion detector 110, and the length direction of the flight tube may be perpendicular to the horizontal direction of the chamber.

The mass spectrometry apparatus according to an embodiment may simultaneously perform high-definition image analysis and mass analysis by combining a MALDI-TOF or LDI-TOF with a vertical vision system in a simple structure. For example, the mass spectrometry apparatus may include a high-resolution vision system as a Laser Desorption/Ionization-Time of flight (LDI-TOF) system using a high-resolution laser beam of 5 μm or less. The mass spectrum may be analyzed by analyzing the time of flight through which the laser 120 irradiates the laser light onto the sample 140 and passes through the flight tube through the ion detector 110. In addition, at the same time, the camera 130 can be used to check where the laser is irradiated on the sample.

The MALDI-TOF mass spectrometer (Matrix Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometer) is an effective ionization method for ions with a high molecular weight. It is a method of mixing a small molecular organic substance called a matrix and an analytical sample. In contrast, LDI (Laser Desorption/Ionization) ionization is used to directly ionize by laser without using a matrix. The wavelength of the laser used and the absorption of the material to be analyzed are important factors. For example, organic materials used in OLED show good ionization sensitivity to the UV laser used in this equipment. Accordingly, the mass spectrometry apparatus according to the embodiment may use a 349 nm UV laser.

2 shows a structure of a coaxial laser according to an embodiment. As shown in FIG. 1, when the laser and the camera are arranged in different directions, it is difficult to match the focus. Accordingly, the coaxial laser according to an embodiment may match the optical paths of two lights using a dichroic mirror to match the focus to one position.

The coaxial laser according to an embodiment may include a camera 210, a laser 220, and a dichroic mirror 240. The dichroic mirror 240 refers to a mirror having a property of passing light of a specific wavelength and reflecting light of another specific wavelength.

Specifically, the laser light emitted from the laser 220 passes through the dichroic mirror 240, and visible light reflected from the sample may be reflected by the dichroic mirror 240 to be incident on the camera 210. have.

The laser light may have a wavelength of 349 nm by way of example, but not limited to, and may be 343 nm or more and 355 nm or less. The above figures are exemplary only and are not limited thereto. Meanwhile, the wavelength of visible light reflected from the sample may be 380 nm to 780 nm. According to a difference in wavelength between laser light and visible light, the dichroic mirror may partially transmit and partially reflect.

According to an embodiment, the camera 210 may be disposed parallel to the laser 220 and may further include a mirror 230 at one side. By arranging the mirror 230 at a position where visible light is reflected from the dichroic mirror 240, the camera 210 and the laser 220 may be arranged in parallel.

The camera 210 may be physically connected to the dichroic mirror 240 and the laser 220 to move in one structure. By first aligning the position at which the camera shoots visible light and the position to which the laser light is irradiated, it moves in one structure, moving several areas of the sample, and even if the laser light is irradiated, it is possible to continuously shoot through the camera. .

3 shows a structure of another coaxial laser according to an embodiment. The coaxial laser according to an embodiment may include a camera 310, a laser 320 and a dichroic mirror 340. As shown in FIG. 2, the camera and the laser are not necessarily arranged in parallel, and in another embodiment, a method of vertically placing the laser 320 and the camera 310 is also possible.

In addition, the dichroic mirror 340 of FIG. 3 may operate differently from the dichroic mirror 240 of FIG. 2. Specifically, the dichroic mirror 240 in FIG. 2 reflects visible light and passes the laser light, but the dichroic mirror 340 in FIG. 3 passes visible light and reflects the laser light. This is only exemplary, and it is possible to transform into various structures from the standpoint of a person skilled in the art.

The coaxial laser according to an exemplary embodiment may further include a separate lens for adjusting the focal size of the laser and correcting chromatic and spherical aberration. In one embodiment, a concave lens may be further included so that the focal size of the laser light emitted from the laser 320 may be enlarged, and in some cases, a convex lens may be further included so that the focal size may be reduced. .

In another embodiment, an additional lens (not shown) may be further included in the optical path of the laser light emitted and the optical path of visible light reflected from the sample. The additional lens may be an additional lens for correcting chromatic aberration or spherical aberration.

In the case of using the coaxial laser described in FIGS. 2 and 3, the optical path of laser light irradiated to the sample and the optical path of visible light reflected from the sample can be matched. The dichroic mirror 340 may be used to match light exiting and incident from different devices into one optical path.

4 shows a laser irradiation unit mounted on a mass spectrometer according to an embodiment. The mass spectrometry apparatus 400 according to an embodiment includes an ion detector 410, a first mirror 420, a camera 430, a laser 450, a second mirror 460, and a dichroic mirror 470. It may include.

In FIG. 4, laser light is irradiated to the sample using the first mirror 420 as an example, but in some cases, laser light may be directly irradiated in the form shown in FIG. 1 without the first mirror 420. .

Specifically, the laser light emitted from the laser 450 passes through the dichroic mirror 470 and is reflected by the first mirror 420 to desorb ions of the sample disposed on the plate 490.

The desorbed ions pass through the flight tube and fly to the ion detector 410, and the ion detector 410 may analyze the time of flight (TOF) of the ions to analyze the mass spectrum.

Meanwhile, visible light reflected from the sample is reflected by the first mirror 420 and is incident on the dichroic mirror 470, and the dichroic mirror 470 transmits visible light to the second mirror 460, unlike UV laser light. Can be reflected in the direction. Finally, the visible light reflected from the second mirror 460 is incident on the camera 430, and it is possible to check which area of the sample the laser light is irradiated.

The camera 430, the laser 450, the second mirror 460, and the dichroic mirror 470 are mechanically fixed so that the whole can be moved when any one is moved. The entire configuration refers to a laser irradiation unit or a coaxial laser. Of course, the second mirror 460 may not be included in another embodiment as shown in FIG. 3 according to a modification of a person skilled in the art.

5 shows a state in which two types of samples are placed on a plate according to an embodiment. The thickness of the sample may vary depending on the type. In FIG. 5, for example, a thin sample 520 and a thick sample 521 are respectively disposed on the same plate 530.

In the mass spectrometer, the laser must be irradiated at an appropriate position, and the focal length of the camera must be established at the correct position to obtain a clean image. However, as the thickness of the sample is changed, when mass analysis is performed by placing it on the same plate 530, the distance to the ion detector varies, and a problem in that the laser is not irradiated to an appropriate position may occur.

Accordingly, in FIG. 6, a plate and a plate cover structure capable of maintaining a constant surface height of a sample regardless of the thickness of the sample will be described.

6 shows a plate cover and a sample according to an embodiment. In one embodiment, a sample 620 may be disposed between the plate cover 610 and the plate 630.

The plate cover 610 is first fixed to a predetermined position of the mass spectrometer, and the plate 630 on which the sample 620 is mounted is coupled from below to maintain a constant surface height of the sample. That is, the position of the sample surface in the mass spectrometer is a point where it abuts the plate cover 610 fixed at a specific position. Therefore, it has a constant height regardless of the thickness of the sample and there is no change in the height to which the laser light is irradiated, so more accurate measurement is possible.

According to an embodiment, it is possible to analyze several areas of a sample in a state in which the irradiation point of the laser light and the photographing point of the camera are matched using a coaxial laser (or laser irradiation unit), and a sample using a plate and a plate cover Irrespective of the thickness of the laser can be irradiated at the same height.

The apparatus described above may be implemented as a hardware component, a software component, and/or a combination of a hardware component and a software component. For example, the devices and components described in the embodiments include, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable array (FPA), It can be implemented using one or more general purpose computers or special purpose computers, such as a programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications executed on the operating system. In addition, the processing device may access, store, manipulate, process, and generate data in response to the execution of software. For the convenience of understanding, although it is sometimes described that one processing device is used, one of ordinary skill in the art, the processing device is a plurality of processing elements and/or a plurality of types of processing elements. It can be seen that it may include. For example, the processing device may include a plurality of processors or one processor and one controller. In addition, other processing configurations are possible, such as a parallel processor.

The software may include a computer program, code, instructions, or a combination of one or more of these, configuring the processing unit to behave as desired or processed independently or collectively. You can command the device. Software and/or data may be interpreted by a processing device or to provide instructions or data to a processing device, of any type of machine, component, physical device, virtual equipment, computer storage medium or device. , Or may be permanently or temporarily embodyed in a transmitted signal wave. The software may be distributed over networked computer systems and stored or executed in a distributed manner. Software and data may be stored on one or more computer-readable recording media.

The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like alone or in combination. The program instructions recorded on the medium may be specially designed and configured for the embodiment, or may be known and usable to those skilled in computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs and DVDs, and magnetic media such as floptical disks. -A hardware device specially configured to store and execute program instructions such as magneto-optical media, and ROM, RAM, flash memory, and the like. Examples of program instructions include not only machine language codes such as those produced by a compiler but also high-level language codes that can be executed by a computer using an interpreter or the like. The hardware device described above may be configured to operate as one or more software modules to perform the operation of the embodiment, and vice versa.

Although the embodiments have been described by the limited drawings, various modifications and variations are possible from the above description to those of ordinary skill in the art. For example, the described techniques are performed in a different order from the described method, and/or components such as a system, structure, device, circuit, etc. described are combined or combined in a form different from the described method, or other components Alternatively, even if substituted or substituted by an equivalent, an appropriate result can be achieved.

Therefore, other implementations, other embodiments, and claims and equivalents fall within the scope of the claims to be described later.

Claims (13)

In an apparatus for analyzing a sample by a laser desorption ionization method,
Laser irradiation unit; And
Ion detector for detecting ions desorbed from the sample
Including,
The laser irradiation unit,
A laser irradiating laser light to the sample;
A camera for photographing the sample; And
A dichroic mirror that passes one of the laser light and visible light reflected from the sample and reflects the other
Mass spectrometry device comprising a.
The method of claim 1,
The dichroic mirror,
A mass spectrometry device configured to match an optical path emitted from the laser and irradiated to a sample with the optical path of the camera.
The method of claim 2,
The laser is a mass spectrometer fixed to the camera and the dichroic mirror to move together.
The method of claim 3,
The laser irradiation unit,
A lens disposed in a path through which the laser light exits; And
Chromatic aberration filter for correcting chromatic aberration caused by the lens
Mass spectrometry device further comprising a.
The method of claim 4,
Aspherical mirror reflecting laser light passing through the dichroic mirror to the sample and reflecting visible light reflected from the sample to the dichroic mirror
Mass spectrometry device further comprising a.
The method of claim 5,
The aspherical mirror,
A hole with a size less than a predetermined size so that ions desorbed from the sample pass through
Mass spectrometry device further comprising a.
The method of claim 1,
The ion detector,
A mass spectrometry device that detects ions emitted in a direction substantially perpendicular to the surface of the sample by irradiation with the laser.
The method of claim 7,
A plate on which the sample is placed; And
A plate cover surrounding the plate and the sample and fixed at the same position inside the mass spectrometer regardless of the thickness of the sample
Mass spectrometry device further comprising a.
In the coaxial laser used in the sample mass spectrometry device,
A laser for irradiating a laser to the sample;
A camera for photographing the sample; And
A dichroic mirror that passes one of the laser light and the visible light reflected from the sample and reflects the other
Coaxial laser comprising a.
The method of claim 9,
The dichroic mirror,
A coaxial laser configured to match an optical path emitted from the laser and irradiated to a sample with the optical path of the camera.
The method of claim 10,
The laser is a coaxial laser fixed to the camera and the dichroic mirror and moving together.
The method of claim 11,
A lens disposed in a path through which the laser light exits; And
Chromatic aberration filter for correcting chromatic aberration caused by the lens
Coaxial laser comprising a further.
The method of claim 12,
The laser,
Coaxial laser that emits light with a wavelength of 343 nm or more and 355 nm or less.

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