KR102648081B1 - Inspection system using terahertz wave - Google Patents

Abstract

An inspection system using terahertz waves is provided. The system includes an inspection device that inspects an inspection object using terahertz waves, determines whether the inspection object is defective, and generates inspection data, wherein the inspection device transmits the terahertz waves at a certain speed in a predetermined angle range. An image is generated by integrating and processing a plurality of scan information obtained by focusing the terahertz wave to be incident on the inspection object at a plurality of angles based on the reference focus position, and the inspection device generates the image. The inspection data can be generated by analysis.

Description

Inspection system using terahertz waves {INSPECTION SYSTEM USING TERAHERTZ WAVE}

The present invention relates to an inspection system using terahertz waves that can acquire images using a MEMS mirror and TSOM algorithm to obtain high-resolution images exceeding the fixed resolution limit of terahertz waves.

Terahertz waves are electromagnetic waves located in the region between infrared and microwaves, and generally have a frequency between 0.1 THz and 10 THz.

Although continuous research and development has been conducted on these terahertz waves, research is still relatively underdeveloped compared to electromagnetic waves in other wavelength bands. Therefore, this wavelength band is also called the terahertz gap.

However, with continuous development efforts and advancements in other technological fields, such as photonics and nanotechnology, the technology for terahertz waves has recently been further improved.

In particular, interest in terahertz waves continues to increase due to various characteristics such as straightness, permeability to substances, safety to living organisms, and possibility of qualitative confirmation.

As a result, terahertz waves have recently been used in screening devices at airports and security facilities, quality inspection devices for food and pharmaceutical companies, semiconductor inspection devices, dental inspection equipment, gas detection devices, explosives inspection devices, and lab-on-a-chip. Efforts are being made to apply it to various fields such as detectors.

In this way, object inspection using terahertz waves is being carried out in various areas, and the method is also being carried out in various forms. However, various inspection methods using conventional terahertz waves have various problems, such as being costly and time-consuming, and making it difficult to inspect a large area of an object. In addition, in the case of conventional object inspection devices using terahertz waves, there was a problem that the resolution of the terahertz wave detection image was poor.

Korean Patent No. 10-1316568, 2013.10.02

The problem that the present invention aims to solve is to provide an inspection system using terahertz waves.

The problem that the present invention aims to solve is to provide an inspection system using terahertz waves that can acquire images using a MEMS mirror and TSOM algorithm to obtain high-resolution images that exceed the fixed resolution limit of terahertz waves. It is done.

The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned can be clearly understood by those skilled in the art from the description below.

An inspection system using terahertz waves according to an embodiment of the present invention to solve the above-mentioned problems is an inspection system that inspects an inspection object using terahertz waves, determines whether the inspection object is defective, and generates inspection data. It includes a device, wherein the inspection device reflects the terahertz wave at a certain speed or higher in a predetermined angle range and focuses the terahertz wave to be incident on the inspection object at a plurality of angles based on the reference focus position, thereby obtaining the terahertz wave. An image is generated by integrated processing of a plurality of scan information, and the inspection device may analyze the image to generate the inspection data.

In one embodiment of the present invention, the inspection device is provided with a MEMS mirror, and can control the MEMS mirror to focus the terahertz wave to be incident on the inspection object.

In one embodiment of the present invention, the inspection device may correct the plurality of scan information using a TSOM algorithm and generate the image by integrating the corrected plurality of scan information.

In one embodiment of the present invention, a management server that generates the test data of the test object may be further included.

The program according to another embodiment of the present invention is combined with a computer, which is hardware, and is stored in a computer-readable recording medium so that an inspection system using terahertz waves performed by the computer can be performed.

Other specific details of the invention are included in the detailed description and drawings.

According to the present invention, when acquiring an image using terahertz waves, it is possible to obtain a high-resolution image that exceeds the fixed limit resolution of terahertz waves by acquiring the image using a MEMS mirror and a TSOM algorithm. In other words, by acquiring high-resolution images, the inspection time for the inspection object can be shortened.

According to the present invention, by acquiring high-resolution images, it is possible to more accurately determine defects in an inspection object and prevent the production of defective products.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below.

Figure 1 is a block diagram for explaining an inspection system using terahertz waves according to an embodiment of the present invention.
FIG. 2 is a diagram for explaining an inspection device according to an embodiment shown in FIG. 1.
Figure 3 is a diagram for explaining the operation of an inspection system using terahertz waves according to an embodiment of the present invention.

The advantages and features of the present invention, and methods for achieving them, will become clear by referring to the embodiments described in detail below together with the attachments. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various different forms. The present embodiments are merely provided to ensure that the disclosure of the present invention is complete and to provide a general understanding of the technical field to which the present invention pertains. It is provided to fully inform the skilled person of the scope of the present invention, and the present invention is only defined by the scope of the claims.

The terminology used herein is for describing embodiments and is not intended to limit the invention. As used herein, singular forms also include plural forms, unless specifically stated otherwise in the context. As used in the specification, “comprises” and/or “comprising” does not exclude the presence or addition of one or more other elements in addition to the mentioned elements. Like reference numerals refer to like elements throughout the specification, and “and/or” includes each and every combination of one or more of the referenced elements. Although “first”, “second”, etc. are used to describe various components, these components are of course not limited by these terms. These terms are merely used to distinguish one component from another. Therefore, it goes without saying that the first component mentioned below may also be a second component within the technical spirit of the present invention.

Unless otherwise defined, all terms (including technical and scientific terms) used in this specification may be used with meanings commonly understood by those skilled in the art to which the present invention pertains. Additionally, terms defined in commonly used dictionaries are not to be interpreted ideally or excessively unless clearly specifically defined.

In this specification, “computer” includes all various devices that can perform computational processing and provide results to users. For example, computers include not only desktop PCs and laptops (note books), but also smart phones, tablet PCs, cellular phones, PCS phones (Personal Communication Service phones), and synchronous/asynchronous IMT. -2000 (International Mobile Telecommunication-2000) mobile terminals, Palm Personal Computers (Palm PCs), Personal Digital Assistants (PDAs), etc. may also apply. Additionally, if a Head Mounted Display (HMD) device includes computing capabilities, the HMD device may be a computer. Additionally, a computer may be a server that receives requests from clients and performs information processing.

Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings.

FIG. 1 is a block diagram for explaining an inspection system using terahertz waves according to an embodiment of the present invention, and FIG. 2 is a diagram for explaining an inspection device according to an embodiment shown in FIG. 1 .

As shown in FIG. 1, the inspection system 1 using terahertz waves according to an embodiment of the present invention may include an inspection device 10 and an inspection management server 20. At this time, the inspection management server 20 may be omitted.

Here, the inspection device 10 and the inspection management server 20 can transmit and receive data in real-time synchronization using a wireless communication network. The wireless communication network may support various long-distance communication methods, such as Wireless LAN (WLAN), DLNA (Digital Living Network Alliance), Wibro (Wireless Broadband: Wibro), and Wimax (World Interoperability for Microwave Access: Wimax). ), GSM (Global System for Mobile communication), CDMA (Code Division Multi Access), CDMA2000 (Code Division Multi Access 2000), EV-DO (Enhanced Voice-Data Optimized or Enhanced Voice-Data Only), WCDMA (Wideband CDMA) , HSDPA (High Speed Downlink Packet Access), HSUPA (High Speed Uplink Packet Access), IEEE 802.16, Long Term Evolution (LTE), LTEA (Long Term Evolution-Advanced), broadband wireless mobile communication service (Wireless Mobile) Broadband Service: Various communication methods such as WMBS (WMBS), BLE (Bluetooth Low Energy), Zigbee, RF (Radio Frequency), LoRa (Long Range), etc. may be applied, but are not limited to these and include various widely known wireless or mobile communications. method may be applied. Alternatively, the inspection device 10 and the inspection management server 20 may transmit and receive data through wired communication.

First, the inspection device 10 may be a device that can inspect the inspection object 11 in three dimensions using terahertz waves. For example, the inspection device 10 can scan the inspection object 11 for various objects or materials such as food, semiconductor equipment, manufacturing equipment, etc., obtain a three-dimensional image of the inspection object, and inspect it.

As shown in Figures 1 and 2, the examination device 10 according to an embodiment of the present invention includes a Terrawave generating unit 100, a Terrawave irradiating unit 110, a Focus adjusting unit 120, and an Image acquisition unit 130. ), a communication unit 140, a memory unit 150, and a device control unit 160. At this time, the inspection device 10 may be located within the chamber to minimize the influence of the external environment.

In this embodiment, terahertz waves can be interpreted as the same term as terahertz waves, so terahertz waves and terahertz waves can be used simultaneously.

The terahertz wave generation unit 100 can generate terahertz waves. At this time, the generated terahertz wave may have an intensity and pulse width that can be reflected and transmitted when irradiated to the test object 11, but is not limited thereto. For example, the terahertz wave generator 100 can generate terahertz waves consisting of electromagnetic waves with a frequency of 0.1 THz to 10 THz.

The terahertz wave irradiation unit 110 is a device that can irradiate the generated terahertz waves to the test object 11, and adjusts the frequency and irradiation position of the terahertz wave according to the test object 11 to irradiate the terahertz wave with a random angle of incidence. Hertz waves can be irradiated to the test object (11). That is, the terahertz wave irradiation unit 110 can irradiate terahertz waves to the test object 11 by changing the focus position in the x-direction, y-direction, and z-direction.

Depending on the embodiment, the incident angle may be incident parallel to the inspection object 11 or may be incident at an angle with a predetermined angle.

Depending on the embodiment, the terahertz wave irradiation unit 110 may include a lens (not shown) that corrects the angle of incidence of terahertz waves incident on the test object 11. In other words, the lens can adjust the amount of incident light to be larger or smaller. At this time, the lens may include a magnification lens or an optical lens for condensing the angle of incidence, but is not limited thereto. For example, the magnification lens may be a high magnification lens.

The focus adjustment unit 120 may be located between the terahertz wave irradiation unit 110 and the test object 11 to focus the terahertz waves.

The focus adjustment unit 120 may include a MEMS mirror 121 and a lens 122.

The MEMS mirror 121 can reflect terahertz waves at high speed in a predetermined angle range. That is, the MEMS mirror 121 can rotate at high speed within a predetermined angle range. Accordingly, the terahertz wave incident on the MEMS mirror 121 may be reflected at high speed in a predetermined angle range and incident on the lens 122. At this time, in order to reflect the terahertz wave in the uniaxial direction, the MEMS mirror 121 may rotate in the uniaxial direction within a predetermined angle range.

Rotation of the MEMS mirror 121 can be implemented in various forms. For example, by applying a current having a square wave or sine wave of a certain frequency to the motor (not shown) of the MEMS mirror 121, a desired repetitive rotational operation of the MEMS mirror 121 can be obtained. Here, the rotation speed of the MEMS mirror 121 may be 60Hz to 100Hz.

Depending on the embodiment, the rotation angle, motion, speed, etc. of the MEMS mirror 121 may be controlled according to the image acquired from the inspection object 11.

Meanwhile, instead of the MEMS mirror 121, a Galvano mirror or a polygon mirror that can reflect at high speed in a certain angle range can be used.

The lens 122 can collimate the terahertz waves reflected by the MEMS mirror 121. That is, the lens 122 can reflect the terahertz wave reflected by the MEMS mirror 121 in parallel and make it incident on the inspection object 11. At this time, the lens 122 may be implemented as a parabolic mirror.

At this time, the lens 122 may be implemented as a parabolic mirror. For example, the diameter of the parabolic mirror may be 200 mm.

The focus of the lens 122 and the rotation axis of the MEMS mirror 121 may coincide with the parabolic mirror. Accordingly, the terahertz wave may be reflected at a certain angle by the rotation of the MEMS mirror 121, be reflected in parallel by the lens 122, and be incident on the inspection object 11. At this time, it is preferable that the terahertz waves reflected in parallel by the lens 122 are incident perpendicularly to the inspection object 11.

The focus adjustment unit 120 of this structure changes the focus position of the terahertz wave irradiated to the inspection object 11 and can obtain scanned images of the inspection object 11 scanned at various focus positions at high speed.

The image acquisition unit 130 integrates and processes a plurality of scanned images acquired from the inspection object 11 according to various focus positions to produce a TSOM (Through focus Scanning Optical Microscopy) image of the inspection object 11. can be obtained. At this time, the scanned image may be a plurality of images scanned in the x-direction, y-direction, and z-direction with respect to the inspection object 11.

A TSOM image can be obtained by integrating a plurality of scanned images obtained as the relative distance (distance on the optical axis) between the lens 122 and the inspection object 11 changes.

In this embodiment, the image acquisition unit 130 may acquire a TSOM image (TSOM Iimage) through a through-focus scanning optical microscope.

Specifically, the image acquisition unit 130 applies the TSOM algorithm among a plurality of scanned images to correct out-of-focus scanned images according to the focus position using the basic image, and synthesizes the corrected scanned images to obtain a resolution higher than the limit. High-resolution TSOM images can be acquired.

The communication unit 140 may transmit test data about the test object 11 to the test management server 20. Here, the inspection data may include data on which it is determined whether the inspection object 11 is defective. That is, the inspection data may be a TSOM image (TSOM Iimage), which is a 3-dimensional image, and may be data on which the presence or absence of defects in the inspection object 11 is determined.

Depending on the embodiment, the communication unit 140 may transmit a scanned image or a TSOM image to the inspection management server 20.

The memory unit 150 can store data transmitted and received through the communication unit 140 and data supporting various functions of the inspection device 10. The memory unit 150 may store a plurality of application programs (application programs or applications) running on the testing device 10, data for operating the testing device 10, and commands. At least some of these application programs may be downloaded from the examination management server 20 or an external server through wireless communication.

The device control unit 160 may generate inspection data by analyzing a TSOM image (TSOM Iimage) of the inspection object 11 by integrating and processing a plurality of scanned images.

Specifically, the device control unit 160 analyzes a plurality of scanned images included in the acquired TSOM image (TSOM Iimage) and determines the defect area where defects of the inspection object 11 are suspected to determine whether the inspection object 11 is defective. Inspection data that can be used to determine can be generated.

At this time, the device control unit 160 can control the rotation angle, operation, speed, etc. of the MEMS mirror 121 in response to the inspection object 11 and the inspection data of the inspection object 11. However, it is not limited to this, and a control signal of the MEMS mirror 121 can be received from the inspection management server 20.

Depending on the embodiment, the device control unit 160 may inspect the inspection object 11 and, if a defect occurs, perform repair using a laser or a separate repair means. Accordingly, the process time can be shortened by simultaneously performing inspection and repair on the inspection object 11.

Such an inspection device 10 adjusts the focus position of the terahertz wave with respect to the inspection object 11, acquires various scanned images according to various focus positions, and integrates and processes the acquired plurality of scanned images to produce a TSOM image. Using this method, test data for the test object 11 can be generated. It is possible to determine whether the inspection object 11 is defective by more accurately determining the defect area where a defect is suspected.

The examination management server 20 may include a data communication unit 200, a database unit 210, a display unit 220, and a management control unit 230.

The data communication unit 200 can receive inspection data from the inspection device 10.

Depending on the embodiment, the data communication unit 200 may receive a scanned image or a TSOM image from the inspection device 10.

Depending on the embodiment, the data communication unit 200 may transmit a control signal of the MEMS mirror 121 from the inspection device 10.

The database unit 210 can store data transmitted and received from the inspection device 10 through a wired or wireless communication network.

The database unit 210 may store data supporting various functions of the examination management server 20. The database unit 210 may store a number of application programs (application programs or applications) running on the examination management server 20, data for operation of the examination management server 20, and commands. At least some of these applications may be downloaded from an external server via wireless communication.

The display unit 220 displays the operating status of the inspection device 10 by user manipulation, the operating status of the inspection management server 20, and data transmitted and received between the inspection device 10 and the inspection management server 20. It can be monitored through. In other words, by checking the operating status of the inspection device 10 in real time, the manager can quickly respond if an error or breakdown occurs.

The management and control unit 230 can receive inspection data and manage the status of the inspection object 11 to prevent the production of defective products by the inspection object 11.

Depending on the embodiment, the management and control unit 230 may generate inspection data of the inspection object 11 by analyzing the scanned image or TSOM image received from the inspection device 10.

Depending on the embodiment, the management and control unit 230 may generate a control signal of the MEMS mirror 121 in response to the inspection object 11 and the inspection data of the inspection object 11.

The examination management server 20 with this structure may be a computing device implemented by hardware circuits (eg, CMOS-based logic circuits), firmware, software, or a combination thereof. For example, it can be implemented using transistors, logic gates, and electronic circuits in the form of various electrical structures.

The operation of the inspection system using terahertz waves of this configuration is as follows. Figure 3 is a diagram for explaining the operation of an inspection system using terahertz waves according to an embodiment of the present invention.

In this embodiment, the inspection system 1 using terahertz waves is disclosed as operating in the inspection device 10, but is not limited thereto.

First, as shown in FIG. 3, the inspection device 10 can generate terahertz waves (S100). For example, the signal generator 100 may generate a terahertz wave consisting of electromagnetic waves with a frequency of 0.1 THz to 10 THz.

Next, the inspection device 10 can set the reference focus position of the inspection object 11 (S110).

The reference focus position can be set using a stage (not shown) that can move the inspection object 11 in the x-direction, y-direction, and z-direction.

Next, the inspection device 10 may primarily focus the terahertz waves incident on the inspection object 11 based on the reference focus position of the inspection object 11 (S120).

Specifically, the inspection device 10 controls the MEMS mirror 121 to reflect terahertz waves at high speed in a predetermined angle range so that the terahertz waves are incident on the inspection object 11 at various angles based on the reference focus position. You can focus.

Next, the inspection device 10 may acquire a plurality of first scanned images obtained by scanning the inspection object 11 from various angles based on the reference focus position (S130).

Next, the inspection device 10 can adjust the focus position of the inspection object 11 in the x-direction, y-direction, and z-direction (S140).

Specifically, the terahertz wave irradiation unit 110 may irradiate terahertz waves to the test object 11 by changing the x-direction, y-direction, and z-direction based on the reference focus position.

Next, the inspection device 10 can secondarily focus the terahertz waves incident on the inspection object 11 based on the moved focus position of the inspection object 11 (S150).

Specifically, the inspection device 10 controls the MEMS mirror 121 to reflect terahertz waves at high speed in a predetermined angle range so that the terahertz waves are incident on the inspection object 11 at various angles based on the moving focus position. You can focus in two ways.

Next, the inspection device 10 may acquire a plurality of second scanned images that scan the inspection object 11 from various angles based on the moving focus position (S160).

Next, the inspection device 10 can generate a high-resolution TSOM image using a plurality of first and second scanned images (S170).

Specifically, the inspection device 10 applies the TSOM algorithm among the plurality of first and second scanned images to correct out-of-focus scanned images according to the focus position using the basic image, and synthesizes the corrected scanned images. It is possible to acquire high-resolution TSOM images that are higher than the resolution limit.

Finally, the inspection device 10 can generate inspection data by analyzing accurate data about the inspection object 11 using the high-resolution TSOM image (S180).

The steps of the method or algorithm described in connection with embodiments of the present invention may be implemented directly in hardware, implemented as a software module executed by hardware, or a combination thereof. Software modules can be RAM (Random Access Memory), ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable ROM), Flash Memory, hard disk, removable disk, CD-ROM, or It may reside on any type of computer-readable recording medium well known in the art to which the invention pertains.

Above, embodiments of the present invention have been described with reference to the attached drawings, but those skilled in the art will understand that the present invention can be implemented in other specific forms without changing its technical idea or essential features. You will be able to understand it. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive.

1: Inspection system using terahertz waves
10: inspection device
20: Inspection management server

Claims (5)

It includes an inspection device that inspects an inspection object using terahertz waves, determines whether the inspection object is defective, and generates inspection data,
The inspection device is,
The terahertz wave is reflected at a certain speed or higher in a predetermined angle range and focused so that the terahertz wave is incident on the inspection object at a plurality of angles based on a reference focus position to obtain a plurality of first scanned images, and the inspection table The focus position of the terahertz wave irradiated to the test object is changed by moving the upper body in the Acquiring a plurality of second scanned images by focusing them so that they are incident, and generating an image by integrating the obtained plurality of first and second scanned images,
The inspection device is,
An inspection system using terahertz waves that analyzes the image and generates the inspection data. According to paragraph 1,
The inspection device is,
Equipped with a MEMS mirror,
An inspection system using terahertz waves that controls the MEMS mirror to focus the terahertz waves to be incident on the inspection object. According to paragraph 1,
The inspection device is,
An inspection system using terahertz waves that corrects the plurality of scan information using a TSOM algorithm and generates the image by integrated processing of the corrected plurality of scan information. According to paragraph 1,
An inspection system using terahertz waves, further comprising a management server that generates the inspection data of the inspection object. A computer program combined with a computer as hardware and stored on a computer-readable recording medium so as to perform the system of any one of claims 1 to 4.

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