KR102485214B1 - Apparatus and method of executing vision inspection by using a plurality of hologram devices - Google Patents

Abstract

The present invention relates to a technical idea of performing a vision inspection using a plurality of hologram elements, and sequentially projecting moiré pattern images of different wavelengths generated using a plurality of hologram elements onto an inspection target, sequentially It relates to a technology for automatically measuring and inspecting a surface height difference of an inspection target based on moiré pattern images projected onto, a vision inspection apparatus according to an embodiment of the present invention uses a plurality of short-wavelength laser light sources to A laser light source unit that projects a laser beam, a light source controller that selectively drives the plurality of short-wavelength laser light sources to control the output of the plurality of laser beams, and transmits each of the plurality of laser beams according to the controlled output to each of the plurality of hologram elements. A hologram element unit that receives and generates first moire pattern images of different wavelengths and sequentially projects the generated first moire pattern images of different wavelengths onto an inspection target, and the sequentially projected Sequentially photographing first moire pattern images of different wavelengths, and measuring and inspecting the height difference of the inspection target based on the continuity of the sequentially photographed first moire pattern images of different wavelengths A measurement inspection unit may be included.

Description

Vision inspection device and method using a plurality of hologram elements

The present invention relates to a technical idea of performing a vision inspection using a plurality of hologram elements, and sequentially projecting moiré pattern images of different wavelengths generated using a plurality of hologram elements onto an inspection target, sequentially It relates to a technique for automatically measuring and inspecting a surface height difference of an inspection target based on projected moiré pattern images.

An analog vision inspection device according to the prior art uses a grating element in which a pattern of a chromium (Cr) thin film is formed on a transparent glass substrate in order to project a moiré pattern image.

When a light source (white LED light) is projected from behind the grating element, a moiré pattern image is formed and projected by the pattern of the chrome thin film, and this method is the same as the COG (chrome on glass) method commonly used in photolithography.

An analog vision inspection apparatus according to the prior art may be composed of a projector that projects a moiré pattern image and a camera that accurately captures an image of an inspection target on which the moiré pattern image is projected.

In order to observe the front without the influence of shadows, two or more projectors must be mounted.

A projector is generally composed of an LED light source, a condensing lens unit, a grating element, and a piezo actuator for moving the grating element to irradiate an inspection target while shifting a moiré pattern image.

The grating element can be manufactured by making a transmitted light pattern having a sinusoidal intensity and finely etching a thin chromium foil overlaid on glass.

In order to make the intensity of the moiré pattern image become a sine wave, the edge portion of the chrome pattern is finely processed to form a gray scale.

The method of creating and projecting a moiré pattern image by shining LED light behind a grating element has a disadvantage in that it is very difficult to precisely manufacture and it is very difficult to make a small moiré pattern image.

That is, the period of the Moiré pattern that can be obtained with the grating element can be limited by the micro-etch fixation of the chromium thin film.

In addition, since white light is used as a light source, it is difficult to focus in a small size compared to a laser light source, and it is difficult to miniaturize as a grating element of a certain size (area) is necessarily required.

Typically, an analog type vision inspection system has one grating element in a projector and can project only a moiré pattern image corresponding to one wavelength, and accordingly, it is suitable for inspection of an inspection target with a small height difference. can

In order to project multiple moiré pattern images from a single projector, there is a method of creating and projecting pattern images using a digital device such as LCoS (Liquis Crystal on Si).

A digital type vision inspection system is composed of a projector that projects an image similar to an analog type vision inspection system and a camera that captures a pattern image projected on an object to be inspected. The projector can project various images using LCoS devices. there is.

Therefore, instead of moving the image, the moved image can be input to the LCoS device and projected. Therefore, a piezo-actuator is not installed.

The role of the electronic circuit connected to the LCoS element in the projector of the digital type vision inspection system is to create an image to be projected and transfer it to the LCoS element.

However, the digital type vision inspection system has an advantage of being able to create and project multiple pattern images even using one LCoS device, but has a disadvantage in that the structure is complicated and the price is very high.

Korean Patent Registration No. 10-0484637, "Three-dimensional shape measuring device using multi-channel phase shift moiré technique and its method" Korean Patent Registration No. 10-2049749, "Dielectric-based metasurface hologram device and manufacturing method thereof, and display device including the same" Korean Patent Publication No. 10-1876391, "3D inspection device using multi-channel image of monochromatic light moiré" Korean Patent Registration No. 10-1750883, "Method for Measuring 3-D Shape of Vision Inspection System"

The present invention projects moire pattern images of different wavelengths generated using a plurality of hologram elements onto an inspection target, and automatically measures and inspects the surface height difference of the inspection target based on the projected moire pattern image. It is an object of the present invention to provide a vision inspection device and method.

An object of the present invention is to increase the range of measurable height difference by using a plurality of hologram elements and a short-wavelength laser light source and projecting moiré pattern images of different cycles onto an inspection target.

The present invention uses a hologram element that is smaller and lighter than a grating element and uses a short-wavelength laser light source that does not require a condensing lens, so that the intensity distribution of the projected light pattern is precisely provided and the pattern period can be freely adjusted. It aims to provide

The present invention uses a hologram element that is smaller and lighter than a grating element and uses a short-wavelength laser light source that does not require a condensing lens to project a plurality of moiré pattern images having different wavelengths in a simple and lightweight projector. It is an object of the present invention to provide an inspection device.

The present invention uses a plurality of hologram elements and a short-wavelength laser light source, and connects a piezo driver to the plurality of hologram elements and a short-wavelength laser light source to move a plurality of moiré pattern images having different wavelengths while projecting all surfaces of the inspection target It is an object of the present invention to provide a vision inspection device.

The vision inspection device according to an embodiment of the present invention controls the output of the plurality of laser beams by selectively driving the laser light source unit for projecting a plurality of laser beams using a plurality of short-wavelength laser light sources and the plurality of short-wavelength laser light sources. A light source controller that receives each of a plurality of laser beams according to the controlled output in each of a plurality of hologram elements to generate first moire pattern images of different wavelengths, A hologram element unit for sequentially projecting first moire pattern images and sequentially photographing the sequentially projected first moire pattern images of different wavelengths, and sequentially photographing the sequentially photographed first moire pattern images of different wavelengths. 1 may include a measurement inspection unit that measures and inspects a height difference of the inspection target based on continuity of moire pattern images.

A piezo driver connected to the laser light source unit to move projection directions of the plurality of laser beams or connected to the hologram element unit to move positions of the plurality of hologram elements may be further included.

The hologram element unit is based on the shifted projection direction or the moved positions of the plurality of hologram elements, and second moiré patterns of different wavelengths are respectively moved in the generated first moiré pattern images of different wavelengths. (moire) pattern images may be generated, and the generated second moire pattern images of different wavelengths may be sequentially projected onto the inspection target.

The measurement inspection unit sequentially captures and synthesizes the projected first moire pattern images of different wavelengths and the projected second moire pattern images of different wavelengths, so that all surfaces of the inspection target are A composite image in which moiré pattern images of different wavelengths are projected may be generated, and a height difference of the inspection target may be measured and inspected based on the continuity of the moiré pattern images in the generated composite image.

The light source control unit controls the conversion of the generated first moiré pattern images of different wavelengths by sequentially supplying power to each of the plurality of short-wavelength laser light sources and controlling the output of the plurality of laser beams. there is.

Each of the plurality of hologram elements may include one of a meta hologram element related to a moire pattern image and a diffractive optical element (DOE) hologram element.

Any one of the plurality of hologram elements may generate a moiré pattern image of a short wavelength, and any one of the plurality of hologram elements may generate a moiré pattern image of a long wavelength.

A vision inspection device using a plurality of hologram elements according to an embodiment of the present invention includes a laser light source unit for projecting a single laser beam using a single short-wavelength laser light source, dividing the single laser beam into a plurality of laser beams, A light source control unit that selectively outputs the divided plurality of laser beams and controls the output of the divided plurality of laser beams, and accommodates each of the plurality of laser beams according to the controlled output in each of the plurality of hologram elements to have different wavelengths. A hologram element unit that generates first moire pattern images of and sequentially projects the generated first moire pattern images of different wavelengths onto an inspection target, and the sequentially projected first moire pattern images of different wavelengths. 1 including a measurement inspection unit for sequentially photographing moire pattern images and measuring and examining a height difference of the inspection target based on the continuity of the sequentially photographed first moire pattern images of different wavelengths. can

The light source control unit controls a beam splitting unit dividing the one laser beam into the plurality of laser beams, the direction of the divided plurality of laser beams, and transmits the divided plurality of laser beams according to the adjusted direction. and a shutter unit for selectively outputting the plurality of transmitted laser beams and controlling conversion of the generated first moire pattern images of different wavelengths.

According to one embodiment of the present invention, the vision inspection device may further include a piezo driver connected to the hologram element unit to move the positions of the plurality of hologram elements.

The hologram element unit converts second moiré pattern images of different wavelengths to which the positions of patterns are respectively moved from the generated first moiré pattern images of different wavelengths based on the positions of the moved plurality of hologram elements. generating, and sequentially projecting the generated second moire pattern images of different wavelengths onto the inspection target.

The measurement inspection unit sequentially captures and synthesizes the projected first moire pattern images of different wavelengths and the projected second moire pattern images of different wavelengths, and then covers all surfaces of the inspection target. A composite image in which moiré pattern images of different wavelengths are projected may be generated, and a height difference of the inspection target may be measured and inspected based on the continuity of the moiré pattern images in the generated composite image.

A vision inspection method according to an embodiment of the present invention includes projecting a plurality of laser beams using a plurality of short-wavelength laser light sources or projecting a single laser beam using a single short-wavelength laser light source in a laser light source unit, and a light source control unit. In the case of using the plurality of short-wavelength laser light sources, selectively driving the plurality of short-wavelength laser light sources to control the output of the plurality of laser beams, and when using the one short-wavelength laser light source, the one laser beam Dividing into a plurality of laser beams and selectively outputting the divided plurality of laser beams to control the output of the divided plurality of laser beams, in the hologram element unit, each of the plurality of laser beams according to the controlled output receiving in each of a plurality of hologram elements to generate first moire pattern images of different wavelengths, and sequentially projecting the generated first moire pattern images of different wavelengths onto an inspection target; and In the measurement inspection unit, the projected first moire pattern images of different wavelengths are sequentially photographed, and the inspection target is based on the continuity of the sequentially photographed first moire pattern images of different wavelengths. A step of measuring the height difference of may be included.

The vision inspection method according to an embodiment of the present invention includes moving the projection direction of the plurality of laser beams or moving the positions of the plurality of hologram elements in the piezo drive unit, and moving the moved projection in the hologram element unit. Based on the direction or the position of the moved plurality of hologram elements, second moire pattern images of different wavelengths in which the position of the pattern is moved in the generated first moiré pattern images of different wavelengths are respectively generated, and , sequentially projecting the generated second moire pattern images of different wavelengths onto the inspection target, and in the measurement inspection unit, the projected first moire pattern images of different wavelengths and the Projected second moire pattern images of different wavelengths are sequentially photographed and synthesized to generate a composite image in which moire pattern images of different wavelengths are projected on all surfaces of the inspection target, and in the generated composite image The method may further include measuring and inspecting a height difference of the inspection target based on the continuity of the moiré pattern image.

The present invention projects moire pattern images of different wavelengths generated using a plurality of hologram elements onto an inspection target, and automatically measures and inspects the surface height difference of the inspection target based on the projected moire pattern image. A vision inspection device and method may be provided.

According to the present invention, a range of measurable height differences can be increased by using a plurality of hologram elements and a short-wavelength laser light source and projecting moiré pattern images of different cycles onto an object to be inspected.

The present invention uses a hologram element that is smaller and lighter than a grating element and uses a short-wavelength laser light source that does not require a condensing lens, so that the intensity distribution of the projected light pattern is precisely provided and the pattern period can be freely adjusted. can provide.

The present invention uses a hologram element that is smaller and lighter than a grating element and uses a short-wavelength laser light source that does not require a condensing lens to project a plurality of moiré pattern images having different wavelengths in a simple and lightweight projector. An inspection device can be provided.

The present invention uses a plurality of hologram elements and a short-wavelength laser light source, and connects a piezo driver to the plurality of hologram elements and a short-wavelength laser light source to move a plurality of moiré pattern images having different wavelengths while projecting all surfaces of the inspection target A vision inspection device may be provided.

1A and 1B are diagrams illustrating the operation concept of a vision inspection device according to an embodiment of the present invention.
2 is a diagram illustrating components of a vision inspection device according to an embodiment of the present invention.
3 and 4 are views illustrating a vision inspection device using a plurality of laser light sources and a hologram element according to an embodiment of the present invention.
5 is a diagram illustrating a vision inspection device using a single laser light source and a plurality of hologram elements according to an embodiment of the present invention.
6A and 6B are views illustrating a moiré pattern image projected from a vision inspection device according to an embodiment of the present invention.
7 is a diagram illustrating a moiré pattern image generated and projected while moving the image in the vision inspection apparatus according to an embodiment of the present invention.
8 is a diagram illustrating a vision inspection method according to an embodiment of the present invention.

Hereinafter, various embodiments of this document will be described with reference to the accompanying drawings.

Examples and terms used therein are not intended to limit the technology described in this document to specific embodiments, and should be understood to include various modifications, equivalents, and/or substitutes of the embodiments.

In the following description of various embodiments, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the invention, the detailed description will be omitted.

In addition, terms to be described below are terms defined in consideration of functions in various embodiments, and may vary according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout this specification.

In connection with the description of the drawings, like reference numerals may be used for like elements.

Singular expressions may include plural expressions unless the context clearly dictates otherwise.

In this document, expressions such as "A or B" or "at least one of A and/or B" may include all possible combinations of the items listed together.

Expressions such as "first," "second," "first," or "second," may modify the corresponding components regardless of order or importance, and are used to distinguish one component from another. It is used only and does not limit the corresponding components.

When a (e.g., first) element is referred to as being "(functionally or communicatively) coupled to" or "connected to" another (e.g., second) element, that element refers to the other (e.g., second) element. It may be directly connected to the component or connected through another component (eg, a third component).

In this specification, "configured to (or configured to)" means "suitable for," "having the ability to," "changed to" depending on the situation, for example, hardware or software ," can be used interchangeably with "made to," "capable of," or "designed to."

In some contexts, the expression "device configured to" can mean that the device is "capable of" in conjunction with other devices or components.

For example, the phrase "a processor configured (or configured) to perform A, B, and C" may include a dedicated processor (eg, embedded processor) to perform the operation, or by executing one or more software programs stored in a memory device. , may mean a general-purpose processor (eg, CPU or application processor) capable of performing corresponding operations.

Also, the term 'or' means 'inclusive or' rather than 'exclusive or'.

That is, unless otherwise stated or clear from the context, the expression 'x employs a or b' means any one of the natural inclusive permutations.

Terms such as '..unit' and '..group' used below refer to a unit that processes at least one function or operation, and may be implemented by hardware or software, or a combination of hardware and software.

1A and 1B are diagrams illustrating the operation concept of a vision inspection device according to an embodiment of the present invention.

Figure 1a illustrates the operation of a vision inspection device using a plurality of hologram elements according to an embodiment of the present invention.

Referring to FIG. 1A , according to an embodiment of the present invention, a vision inspection device is a device for automatically measuring a phase difference such as a height difference on the surface of an inspection target, and a projector that projects a moiré pattern image having a periodic contrast pattern. (100) and a camera for capturing the projected moiré pattern image.

For example, the vision inspection device is composed of a projector 100 and a camera 120, and the projector 100 includes a plurality of hologram elements to generate moiré pattern images of different wavelengths and generated different wavelengths. After sequentially projecting the moiré pattern images of the inspection target 110, the camera 120 sequentially photographs the moiré pattern images of different wavelengths projected on the inspection target 110, and the vision inspection device sequentially photographs the images. It is possible to measure and inspect the height difference of the inspection target based on the continuity of the moiré pattern images of different wavelengths.

According to one embodiment of the present invention, the vision inspection apparatus projects a moiré pattern image having periodic contrast on the surface of the inspection target 110 to be inspected in order to measure the difference in height of the surface of the inspection target 110. If there is no difference, the continuity of the projected moiré pattern image is maintained, but if there is a height difference, the continuity of the moiré pattern image is lost in the portion where the height difference exists, and the pattern is moved, resulting in a phase difference.

The vision inspection apparatus may inversely calculate a height difference from the phase difference and determine whether or not a height difference has occurred in an object to be inspected.

1B illustrates a photographed image of a moiré pattern image projected on a wall having irregularities by a vision inspection device using a plurality of hologram elements according to an embodiment of the present invention.

Referring to FIG. 1B , images 130 and 140 are photographed images of a moiré pattern image projected on a wall having irregularities, and confirm a height difference in an object having irregularities.

Image 130 shows that the phase of the moiré pattern image does not change because there is no height difference at point 131, and the phase of the moiré pattern image is changed according to the height difference according to the unevenness at points 132 and 133. indicates that

The image 140 shows that the phase of the moiré pattern image does not change because there is no height difference at point 141, and the phase of the moiré pattern image is changed at point 142 according to the height difference according to irregularities.

In other words, at points 131 and 141, the phase of the moiré pattern image is continuous, but at the point 132, point 133, and point 142 where the height difference exists, the satellite of the moiré pattern image is changed. indicates that

When calculating the height difference from the phase difference of the moiré pattern, if the phase difference is as much as 2π, the height difference cannot be calculated because the phase difference is not actually detected.

That is, there is a problem in that it is impossible to distinguish between a case where the phase difference is as much as Δφ and a case as much as Δφ + 2π.

Therefore, in this case, the two cases can be distinguished only when the moiré pattern images having different periods (wavelengths) are respectively projected.

If the height difference to be measured is small, the height difference can be measured by scanning only one moiré pattern image with an appropriate period (wavelength). Since there may be cases, it indicates that the projector should be able to project a plurality of moiré pattern images of different wavelengths in order to measure the height difference.

2 is a diagram illustrating components of a vision inspection device according to an embodiment of the present invention.

2 illustrates components of a vision inspection device according to an embodiment of the present invention.

Referring to FIG. 2 , the vision inspection device 200 according to an embodiment of the present invention includes a laser light source unit 210, a light source control unit 220, a hologram element unit 230, and a measurement inspection unit 240.

According to one embodiment of the present invention, the vision inspection device 200 may be a device for measuring and inspecting a surface height difference of an inspection target using a plurality of hologram elements and a short-wavelength laser light source.

For example, the laser light source unit 210 projects a plurality of laser beams using a plurality of short-wavelength laser light sources or projects a single laser beam using a single short-wavelength laser light source.

The laser light source unit 210 may sequentially output a plurality of laser beams under the control of the light source controller 220 .

According to an embodiment of the present invention, the light source controller 220 can control the output of a plurality of laser beams by selectively driving a plurality of short-wavelength laser light sources.

For example, the light source controller 220 may control conversion of first moire pattern images of different wavelengths by sequentially supplying power to each of a plurality of short-wavelength laser light sources and controlling the output of a plurality of laser beams. there is.

According to an embodiment of the present invention, the light source controller 220 can divide one laser beam into a plurality of laser beams and selectively output the divided plurality of laser beams to control the output of the plurality of divided laser beams. there is.

Specifically, the light source control unit 220 controls the direction of the beam splitting unit that divides one laser beam into the plurality of laser beams, the plurality of divided laser beams, and divides the plurality of laser beams according to the adjusted direction. It may include a mirror unit for transmitting and a shutter unit for controlling conversion of first moire pattern images of different wavelengths generated by selectively outputting the plurality of transferred laser beams.

That is, the light source controller 220 may control the output of one or more laser beams projected from the laser light source unit 210 and deliver the plurality of laser beams according to the controlled output to the hologram element unit 230 .

According to an embodiment of the present invention, the hologram element unit 230 receives each of a plurality of laser beams according to the output controlled by the light source controller 220 in each of the plurality of hologram elements, and the first moiré of different wavelengths. ) pattern images, and the generated first moire pattern images of different wavelengths may be sequentially projected onto the inspection target.

Here, the plurality of hologram elements generate first moiré pattern images of different wavelengths.

For example, one of a plurality of hologram elements may generate a short-wavelength moiré pattern image, and one of the plurality of hologram elements may generate a long-wavelength moiré pattern image.

For example, each of the plurality of hologram elements may include any one of a meta hologram element related to a moire pattern image and a diffractive optical element (DOE) hologram element.

That is, the plurality of hologram elements may be meta hologram elements or DOE hologram elements capable of generating a moiré pattern image.

For example, the meta-hologram element reflects the received short-wavelength laser light source based on a plurality of nanostructures and controls the phase of the reflected short-wavelength laser light source to form and project a hologram image corresponding to the moiré pattern image. can

On the other hand, the DOE hologram element includes a diffractive optical element, passes an accepted short-wavelength laser light source, and selectively reflects the passed short-wavelength laser light source to form and project a hologram image corresponding to a moiré pattern image. .

Therefore, the present invention uses a hologram element that is smaller and lighter than a grating element and uses a short-wavelength laser light source that does not require a condensing lens to precisely provide the intensity distribution of the projection light pattern and freely adjust the pattern period. An inspection device can be provided.

In addition, the present invention uses a hologram element that is smaller and lighter than a grating element and uses a short-wavelength laser light source that does not require a condensing lens to project a plurality of moiré pattern images having different wavelengths in a simple and lightweight projector. It is possible to provide a vision inspection device that does.

According to an embodiment of the present invention, the measurement inspection unit 240 sequentially captures the sequentially projected first moire pattern images of different wavelengths, and sequentially captures the sequentially captured first moire pattern images of different wavelengths. Based on the continuity of the pattern images, the height difference of the inspection target can be measured and inspected.

For example, the measurement inspection unit 240 may correspond to the camera described in FIG. 1A, and the laser light source unit 210, the light source control unit 220, and the hologram element unit 230 may be included in the projector.

According to one embodiment of the present invention, the vision inspection device 200 may further include a piezo actuator 250 .

For example, the piezo driver 250 is connected to the laser light source unit 210 to move the projection direction of a plurality of laser beams or connected to the hologram element unit 230 to move the positions of the plurality of hologram elements. .

In other words, the piezo driver 250 may be used to generate second moire pattern images in which patterns are partially moved within first moire pattern images of different wavelengths, or the projection direction of a plurality of short-wavelength laser light sources or Positions of the plurality of hologram elements may be finely adjusted so that positions of laser beams received by the plurality of hologram elements are changed.

According to one embodiment of the present invention, in the hologram element unit 230, the positions of the patterns in the first moiré pattern images of different wavelengths generated based on the moved projection direction or the positions of the plurality of hologram elements are respectively moved. Second moire pattern images of different wavelengths may be generated, and the generated second moire pattern images of different wavelengths may be sequentially projected onto the inspection target.

For example, the measurement inspection unit 240 sequentially captures and synthesizes the projected first moiré pattern images of different wavelengths and the projected second moiré pattern images of different wavelengths, and then synthesizes the object to be inspected. A composite image in which moiré pattern images of different wavelengths are projected on all surfaces is generated, and the height difference of the inspection target may be measured and inspected based on the continuity of the moiré pattern images in the generated composite image.

Therefore, the present invention can increase the range of measurable height difference by using a plurality of hologram elements and a short-wavelength laser light source and projecting moiré pattern images of different cycles onto an inspection target.

For example, the first moiré pattern images and the second moiré pattern images are formed by partially moving the pattern within the moiré pattern image under the control of the piezo driving unit 250, and additionally by the piezo driving unit 250, a third moiré pattern image is formed. Moiré pattern images, fourth moiré pattern images, and Nth moiré pattern images may be generated.

3 and 4 are views illustrating a vision inspection device using a plurality of laser light sources and a hologram element according to an embodiment of the present invention.

Referring to FIG. 3, a projector of a vision inspection device using a plurality of laser light sources and a plurality of hologram elements according to an embodiment of the present invention is illustrated.

For example, the projector 300 includes a laser light source unit 310, a light source controller 320, and a hologram element unit 330, based on a plurality of hologram elements capable of generating moiré pattern images of different wavelengths. Moiré pattern images of different wavelengths are generated, and the moiré pattern images of different wavelengths may correspond to the long-wavelength moiré pattern image 340 and the short-wavelength moiré pattern image 341 .

According to an embodiment of the present invention, the laser light source unit 310 includes a first short-wavelength laser light source 311 and a second short-wavelength laser light source 312, and the first short-wavelength laser light source 311 and the second short-wavelength laser light source ( 312) A short-wavelength laser beam can be projected from each.

The light source control unit 320 is connected to the laser light source unit 310 through an electronic circuit and controls outputs of the first short-wavelength laser light source 311 and the second short-wavelength laser light source 312 .

For example, the light source controller 320 sequentially controls the power supplied to the first short-wavelength laser light source 311 and the second short-wavelength laser light source 312 to generate the first short-wavelength laser light source 311 and the second short-wavelength laser light source ( By controlling the output of the plurality of laser beams output from 312), the long-wavelength moiré pattern image 340 and the short-wavelength moiré pattern image 341 can be controlled to be sequentially projected.

For example, the light source controller 320 is an electronic circuit and may serve as an optical shutter by sequentially supplying power to a laser light source.

According to one embodiment of the present invention, the hologram element unit 330 includes a first hologram element 331 and a second hologram element 332, and the first hologram element 331 generates a long-wavelength moiré pattern image 340. After generating and projecting, the second hologram element 332 may generate and project the short-wavelength moiré pattern image 341 .

For example, the projector 300 sequentially projects the long-wavelength moiré pattern image 340 and the short-wavelength moiré pattern image 341 even when the height difference is large, even when the phase difference occurs by Δφ and Δφ + 2π. It can support measuring and inspecting the height difference on the surface of the inspection object.

In addition, the projector 300 uses multiple laser light sources having the same wavelength and attaches hologram elements of moiré pattern images having different wavelengths to each laser light source, respectively, so that the laser light sources are selectively operated to mutually Since moiré pattern images of different wavelengths can be projected onto the inspection target, additional optical elements such as light concentrators can be removed and miniaturization is possible, and digital devices such as liquid crystal on Si (LCOS) according to the prior art are not required.

That is, the vision inspection device according to an embodiment of the present invention is an analog type vision inspection device, and may be a vision inspection device using a projector including a plurality of hologram elements and a short-wavelength laser light source.

4 illustrates a case in which a piezo driver is additionally included in a projector of a vision inspection device using a plurality of laser light sources and a plurality of hologram elements according to an embodiment of the present invention.

Referring to FIG. 4 , the projector 400 of the vision inspection device using a plurality of laser light sources and a plurality of hologram elements according to an embodiment of the present invention includes a laser light source unit 410, a light source controller 420, and a hologram element unit ( 430) and a piezo driver 440, based on a plurality of hologram elements capable of generating moiré pattern images of different wavelengths, generating moiré pattern images of different wavelengths, and generating moiré pattern images of different wavelengths. Moiré pattern images of different wavelengths may be additionally generated while partially changing patterns in the images.

According to an embodiment of the present invention, the laser light source unit 410 includes a first short-wavelength laser light source 411 and a second short-wavelength laser light source 412, and the first short-wavelength laser light source 411 and the second short-wavelength laser light source ( 412) A short-wavelength laser beam can be projected from each.

The light source control unit 420 is connected to the laser light source unit 410 through an electronic circuit and controls outputs of the first short-wavelength laser light source 411 and the second short-wavelength laser light source 412 .

For example, the light source controller 420 sequentially controls the power supplied to the first short-wavelength laser light source 411 and the second short-wavelength laser light source 412 so that the first short-wavelength laser light source 411 and the second short-wavelength laser light source ( By controlling the output of the plurality of laser beams output in 412), the plurality of long-wavelength moiré pattern images and the plurality of short-wavelength moiré pattern images may be projected.

For example, the light source controller 420 is an electronic circuit and may serve as an optical shutter by sequentially supplying power to a laser light source.

According to one embodiment of the present invention, the hologram element unit 430 includes a first hologram element 431 and a second hologram element 432, and the first hologram element 431 generates a plurality of long-wavelength moiré pattern images. and projecting, and the second hologram element 432 may generate and project a plurality of short-wavelength moiré pattern images.

For example, the piezo driver 440 is connected to the laser light source 410, and as the projection direction of the first short-wavelength laser light source 411 is moved, the first hologram element 431 generates the first long-wavelength moiré pattern image 450. to the fourth long-wavelength moiré pattern image 453 can be controlled to be generated and projected.

In addition, the piezo driver 440 is connected to the laser light source 410, and as the projection direction of the second short-wavelength laser light source 412 is moved, the second hologram element 432 generates the first short-wavelength moiré pattern image 454. to the fourth short-wavelength moiré pattern image 457.

For example, the first long-wavelength moiré pattern image 450, the second long-wavelength moiré pattern image 451, the third long-wavelength moiré pattern image 452, and the fourth long-wavelength moiré pattern image 453 are formed by partially moving the pattern. It is formed with the same long wavelength as the moiré pattern image.

Meanwhile, the first short-wavelength moiré pattern image 454, the second short-wavelength moiré pattern image 455, the third short-wavelength moiré pattern image 456, and the fourth short-wavelength moiré pattern image 457 are moire patterns formed by partially moving the pattern. It is formed with the same short wavelength as the image.

Here, the partial movement of the pattern is the movement of the moiré pattern image by π/2, and the first long-wavelength moiré pattern image 450 to the fourth long-wavelength moiré pattern image 453 are sequentially projected, and then the captured images are synthesized. In this case, a composite image in which all surfaces of the object to be inspected may be projected.

In addition, when the captured images are synthesized after sequentially projecting the first short-wavelength moiré pattern image 454 to the fourth short-wavelength moiré pattern image 457, a synthesized image in which all surfaces of the inspection target are projected can be generated. there is.

Therefore, the present invention uses a plurality of hologram elements and a short-wavelength laser light source, and connects a piezo driver to the plurality of hologram elements and a short-wavelength laser light source to move a plurality of moiré pattern images having different wavelengths while moving all surfaces of the inspection target. It is possible to provide a vision inspection device that projects.

5 is a diagram illustrating a vision inspection device using a single laser light source and a plurality of hologram elements according to an embodiment of the present invention.

5 illustrates a projector of a vision inspection device using a single laser light source and a plurality of hologram elements according to an embodiment of the present invention.

Referring to FIG. 5 , a projector 500 according to an embodiment of the present invention includes a laser light source unit 510, a light source controller 520, and a hologram element unit 530.

The laser light source unit 510 according to an embodiment of the present invention projects one laser beam by using one short-wavelength laser light source.

For example, the light source controller 520 includes a beam splitting unit 521, a first mirror unit 522, a second mirror unit 523, a first shutter unit 524, and a second shutter unit 525. .

According to one embodiment of the present invention, the beam splitting unit 521 divides one laser beam into a plurality of laser beams and transmits them to the first mirror unit 522 and the second mirror unit 523, respectively.

For example, the first mirror unit 522 and the second mirror unit 523 adjust directions of a plurality of divided laser beams, and transmit the divided laser beams to the shutter unit according to the adjusted directions.

According to one embodiment of the present invention, the first shutter unit 524 and the second shutter unit 525 selectively output a plurality of delivered laser beams to control the conversion of moiré pattern images of different wavelengths. can

For example, the first mirror unit 522 may be related to the first shutter unit 524 and the second mirror unit 523 may be related to the second shutter unit 525 .

According to one embodiment of the present invention, the hologram element unit 530 includes a first hologram element 531 and a second hologram element 532, and the first hologram element 531 converts a long-wavelength moiré pattern image into a hologram image. , and the second hologram element 532 may generate and project a moiré pattern image of a short wavelength as a hologram image.

That is, the hologram element unit 530 may generate and project moiré pattern images of different wavelengths.

The projector 500 according to an embodiment of the present invention separates one short-wavelength laser light source using the beam splitting unit 521, and the first shutter unit 524 and the second shutter unit 525 and the first hologram By passing through the element 531 and the second hologram element 532, a long-wavelength moiré pattern image 540 and a short - wavelength moiré pattern image 541 may be generated.

In addition, the projector 500 additionally includes a piezo driver (not shown) to adjust the positions of a plurality of hologram elements, respectively, to generate moiré pattern images of different wavelengths in which patterns in the moiré pattern images of different wavelengths are partially moved. can

That is, the piezo driver (not shown) adjusts the positions of the first hologram element 531 and the second hologram element 532 to obtain a moiré pattern image of different wavelengths in which the patterns in the moiré pattern image of different wavelengths are partially moved. can create

6A and 6B are views illustrating a moiré pattern image projected from a vision inspection device according to an embodiment of the present invention.

6A and 6B illustrate a computer simulation image of a hologram element implementing a moiré pattern image having a sinusoidal intensity distribution and a line scan of brightness.

Referring to the image 600 and graph 601 of FIG. 6A and the image 610 and graph 611 of FIG. 6B , monochromatic light is projected onto the hologram element used in the vision inspection device according to an embodiment of the present invention. It can be confirmed that a moiré pattern image having a sinusoidal intensity distribution is implemented.

In addition, the image 600 and graph 601 and the image 610 and graph 611 of FIG. 6B indicate that moiré pattern images of different wavelengths are implemented.

7 is a diagram illustrating a moiré pattern image generated and projected while moving the image in the vision inspection apparatus according to an embodiment of the present invention.

7 illustrates generating various moiré pattern images while partially moving a pattern within a moiré pattern image using a piezo drive unit in the vision inspection apparatus according to an embodiment of the present invention.

Referring to FIG. 7 , a first moiré pattern image 700, a second moiré pattern image 710, a third moiré pattern image 720, and a fourth moiré pattern image 730 are exemplified, and within each moiré pattern image Pattern changes are shown based on the baseline.

That is, the reference line 701, the reference line 711, and the reference line within the first moire pattern image 700, the second moire pattern image 710, the third moire pattern image 720, and the fourth moire pattern image 730. The first moiré pattern image 700, the second moiré pattern image 710, the third moiré pattern image 720, and the fourth moiré pattern image 730 are different from each other through the change of the reference line 721 and the reference line 731. It can be confirmed that the pattern is a moiré pattern image.

Here, the movement of the reference line 701, the reference line 711, the reference line 721, and the reference line 731 is π/2, but the movement distance may be changed according to the control of the piezo actuator.

After sequentially projecting the first moiré pattern image 700, the second moiré pattern image 710, the third moiré pattern image 720, and the fourth moiré pattern image 730 onto the inspection target, the captured image is captured. When composited into one, you can get a picture in which all sides are projected with the brightest light.

Therefore, the vision inspection device according to an embodiment of the present invention detects a fine local difference in height, obtains an image in which the brightest light is projected on all surfaces of the inspection target, and detects angles such as microcracks and corners. Information can also be obtained.

8 is a diagram illustrating a vision inspection method according to an embodiment of the present invention.

8 illustrates a method of measuring and inspecting a height difference of an inspection target using a projector and a camera using a plurality of hologram elements and a short-wavelength laser light source in the vision inspection method according to an embodiment of the present invention.

Referring to FIG. 8 , in step 801, the vision inspection method according to an embodiment of the present invention determines whether a plurality of short-wavelength laser light sources are used.

That is, the vision inspection method proceeds to step 802 when a plurality of short-wavelength laser light sources are used, and proceeds to step 803 when one short-wavelength laser light source is used.

In step 802, the vision inspection method according to an embodiment of the present invention selectively drives a plurality of short-wavelength laser light sources to control the output of a plurality of laser beams.

That is, the vision inspection method may control the output of a plurality of laser beams by sequentially supplying power to each of a plurality of short-wavelength laser light sources.

In step 803, the vision inspection method according to an embodiment of the present invention divides one laser beam into a plurality of laser beams, and selectively outputs the divided plurality of laser beams to control the output of the plurality of laser beams. .

That is, the vision inspection method can control the output of a plurality of laser beams by dividing one laser beam into a plurality of laser beams and selectively outputting them by using a beam splitter, a mirror unit, and a shutter unit.

In step 804, the vision inspection method according to an embodiment of the present invention receives a plurality of laser beams in different hologram elements to generate moiré pattern images of different wavelengths, and generates moiré pattern images of different wavelengths. project them onto the object of examination.

That is, the vision inspection method receives a plurality of laser beams controlled in step 802 or step 803 in a plurality of hologram elements, generates moiré pattern images of different wavelengths in each of the plurality of hologram elements, and generates Moiré pattern images of different wavelengths are sequentially projected onto the inspection target.

In step 805, in the vision inspection method according to an embodiment of the present invention, moiré pattern images of different wavelengths projected onto the inspection target are photographed, and based on the continuity of the photographed moiré pattern images of different wavelengths, the image of the inspection target is captured. Measure and inspect the height difference.

That is, the vision inspection method sequentially captures moiré pattern images of different wavelengths projected on the inspection target, and measures the height difference of the inspection target based on the continuity of the moiré pattern within the sequentially captured moiré pattern images of different wavelengths. can be measured and inspected.

Therefore, the present invention projects moire pattern images of different wavelengths generated using a plurality of hologram elements onto an inspection target, and automatically measures the difference in height of the surface of the inspection target based on the projected moire pattern image. It is possible to provide a vision inspection device and method for inspection.

The devices described above may be implemented as hardware components, software components, and/or a combination of hardware components and software components. For example, devices and components described in the embodiments may include, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable array (FPA), It may be implemented using one or more general purpose or special purpose computers, such as a programmable logic unit (PLU), microprocessor, or any other device capable of executing and responding to instructions. A processing device may run an operating system (OS) and one or more software applications running on the operating system. A processing device may also access, store, manipulate, process, and generate data in response to execution of software. For convenience of understanding, there are cases in which one processing device is used, but those skilled in the art will understand that the processing device includes a plurality of processing elements and/or a plurality of types of processing elements. It can be seen that it can include. For example, a processing device may include a plurality of processors or a processor and a controller. Other processing configurations are also possible, such as parallel processors.

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 on a computer readable medium. The computer readable medium may include program instructions, data files, data structures, etc. alone or in combination. Program commands 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. - includes hardware devices 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 high-level language codes that can be executed by a computer using an interpreter, as well as machine language codes such as those produced by a compiler. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

Software may include a computer program, code, instructions, or a combination of one or more of the foregoing, which configures a processing device to operate as desired or processes independently or collectively. The device can be commanded. Software and/or data may be any tangible machine, component, physical device, virtual equipment, computer storage medium or device, intended to be interpreted by or provide instructions or data to a processing device. , or may be permanently or temporarily embodied in a transmitted signal wave. Software may be distributed on networked computer systems and stored or executed in a distributed manner. Software and data may be stored on one or more computer readable media.

As described above, although the embodiments have been described with limited drawings, those skilled in the art can make various modifications and variations from the above description. For example, the described techniques may be performed in an order different from the method described, and/or components of the described system, structure, device, circuit, etc. may be combined or combined in a different form than the method described, or other components may be used. Or even if it is replaced or substituted by equivalents, appropriate results can be achieved.

Therefore, other implementations, other embodiments, and equivalents of the claims are within the scope of the following claims.

200: vision inspection device
210: laser light source unit 220: light source control unit
230: hologram element unit 240: measurement inspection unit
250: piezo driving unit

Claims (14)

In the vision inspection device using a plurality of hologram elements,
A laser light source unit for projecting a plurality of laser beams using a plurality of short-wavelength laser light sources;
a light source controller configured to selectively drive the plurality of short-wavelength laser light sources and control the output of the plurality of laser beams;
Each of a plurality of laser beams according to the controlled output is received by each of a plurality of hologram elements to generate first moire pattern images of different wavelengths, and the generated first moire of different wavelengths is applied to the inspection target ( moire) hologram element unit for sequentially projecting pattern images; and
The sequentially projected first moire pattern images of different wavelengths are sequentially photographed, and the height of the inspection target is based on the continuity of the sequentially photographed first moire pattern images of different wavelengths. Including a measurement inspection unit for measuring and inspecting the difference,
A piezo driver connected to the laser light source unit to move the projection direction of the plurality of laser beams or connected to the hologram element unit to move the positions of the plurality of hologram elements;
The hologram element unit is based on the shifted projection direction or the moved positions of the plurality of hologram elements, and second moiré patterns of different wavelengths are respectively moved in the generated first moiré pattern images of different wavelengths. Characterized in that generating (moire) pattern images and sequentially projecting the generated second moire pattern images of different wavelengths to the inspection target
vision inspection device. delete delete According to claim 1,
The measurement inspection unit sequentially captures and synthesizes the projected first moire pattern images of different wavelengths and the projected second moire pattern images of different wavelengths, so that all surfaces of the inspection target are Characterized in that a composite image in which moiré pattern images of different wavelengths are projected is generated, and the height difference of the inspection target is measured and inspected based on the continuity of the moiré pattern image in the generated composite image
vision inspection device. According to claim 1,
The light source controller sequentially supplies power to each of the plurality of short-wavelength laser light sources to control the output of the plurality of laser beams, thereby controlling the conversion of the generated first moire pattern images of different wavelengths. characterized
vision inspection device. According to claim 1,
Characterized in that each of the plurality of hologram elements includes any one of a meta hologram element and a diffractive optical element (DOE) hologram element related to a moire pattern image
vision inspection device. According to claim 1,
Any one of the plurality of hologram elements generates a moiré pattern image of a short wavelength,
Characterized in that any one of the plurality of hologram elements generates a long-wavelength moiré pattern image
vision inspection device. In the vision inspection device using a plurality of hologram elements,
A laser light source unit for projecting a single laser beam using a single short-wavelength laser light source;
a light source control unit that divides the one laser beam into a plurality of laser beams and selectively outputs the divided plurality of laser beams to control output of the divided plurality of laser beams;
Each of a plurality of laser beams according to the controlled output is received in each of a plurality of hologram elements to generate first moire pattern images of different wavelengths, and the generated first moire of different wavelengths is applied to the inspection target ( moire) hologram element unit for sequentially projecting pattern images; and
The sequentially projected first moire pattern images of different wavelengths are sequentially photographed, and the height of the inspection target is based on the continuity of the sequentially photographed first moire pattern images of different wavelengths. Including a measurement inspection unit for measuring and inspecting the difference,
Further comprising a piezo driver connected to the hologram element unit to move the positions of the plurality of hologram elements,
The hologram element unit converts second moire pattern images of different wavelengths, the positions of patterns of which are moved from the generated first moiré pattern images of different wavelengths based on the positions of the moved plurality of hologram elements. characterized in that for generating and sequentially projecting the generated second moire pattern images of different wavelengths onto the inspection target
vision inspection device. According to claim 8,
The light source control unit includes a beam splitting unit dividing the one laser beam into the plurality of laser beams;
a mirror unit for adjusting directions of the plurality of divided laser beams and transmitting the plurality of divided laser beams according to the adjusted direction; and
And a shutter unit that selectively outputs the plurality of transmitted laser beams to control the conversion of the generated first moire pattern images of different wavelengths.
vision inspection device. delete delete According to claim 8,
The measurement inspection unit sequentially captures and synthesizes the projected first moire pattern images of different wavelengths and the projected second moire pattern images of different wavelengths, and then covers all surfaces of the inspection target. Characterized in that a composite image in which moiré pattern images of different wavelengths are projected is generated, and the height difference of the inspection target is measured and inspected based on the continuity of the moiré pattern image in the generated composite image
vision inspection device. In the vision inspection method using a plurality of hologram elements,
In a laser light source unit, projecting a plurality of laser beams using a plurality of short-wavelength laser light sources or projecting a single laser beam using a single short-wavelength laser light source;
In the light source controller, when the plurality of short-wavelength laser light sources are used, the plurality of short-wavelength laser light sources are selectively driven to control the output of the plurality of laser beams, and when the one short-wavelength laser light source is used, the one laser light source dividing a beam into a plurality of laser beams and selectively outputting the divided plurality of laser beams to control output of the divided plurality of laser beams;
In the hologram element unit, each of the plurality of laser beams according to the controlled output is received in each of the plurality of hologram elements to generate first moire pattern images of different wavelengths, and the generated different wavelengths are applied to the inspection target. sequentially projecting first moire pattern images of; and
In the measurement inspection unit, the projected first moire pattern images of different wavelengths are sequentially photographed, and the inspection target is based on the continuity of the sequentially photographed first moire pattern images of different wavelengths. Including the step of measuring the height difference of,
moving the projection direction of the plurality of laser beams or moving the positions of the plurality of hologram elements in a piezo driver;
In the hologram element unit, based on the shifted projection direction or the shifted positions of the plurality of hologram elements, the positions of the patterns in the generated first moiré pattern images of different wavelengths are respectively shifted to the first moiré pattern images of different wavelengths. generating 2 moire pattern images and sequentially projecting the generated second moire pattern images of different wavelengths onto the inspection target; and
In the measurement inspection unit, the projected first moiré pattern images of different wavelengths and the projected second moiré pattern images of different wavelengths are sequentially photographed and synthesized to all surfaces of the inspection target. Generating a composite image onto which the moiré pattern images of different wavelengths are projected, and measuring and examining the height difference of the inspection target based on the continuity of the moiré pattern image in the generated composite image.
Vision inspection method. delete

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