CN113215653A - Method and system for determining distance between liquid ports - Google Patents
Method and system for determining distance between liquid ports Download PDFInfo
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- CN113215653A CN113215653A CN202110468679.7A CN202110468679A CN113215653A CN 113215653 A CN113215653 A CN 113215653A CN 202110468679 A CN202110468679 A CN 202110468679A CN 113215653 A CN113215653 A CN 113215653A
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- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B15/00—Single-crystal growth by pulling from a melt, e.g. Czochralski method
- C30B15/20—Controlling or regulating
- C30B15/22—Stabilisation or shape controlling of the molten zone near the pulled crystal; Controlling the section of the crystal
- C30B15/26—Stabilisation or shape controlling of the molten zone near the pulled crystal; Controlling the section of the crystal using television detectors; using photo or X-ray detectors
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- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
- C30B29/02—Elements
- C30B29/06—Silicon
Abstract
A method and system for determining a fluid gap is provided. The method comprises the following steps: acquiring, by an imaging device, a target image showing an inner lower edge of a guide cylinder and a reflection of the inner lower edge; selecting a first sub-image comprising a first end point and a third end point and a second sub-image comprising a second end point and a fourth end point from the target image; determining pixel coordinates of the first and third end points and pixel coordinates of the second and fourth end points in the first and second sub-images and further in the target image; calculating a first pixel distance between the first end point and the second end point according to the pixel coordinates of the first end point and the second end point in the target image, and calculating a second pixel distance between the third end point and the fourth end point according to the pixel coordinates of the third end point and the fourth end point in the target image; and calculating the liquid port distance at least according to the actual inner diameter of the lower edge of the guide cylinder, the first pixel distance, the second pixel distance and parameters of a lens of the imaging device. The scheme of the invention can measure the liquid port distance with high precision and low cost.
Description
Technical Field
The present invention relates generally to the field of czochralski silicon single crystal production and, more particularly, to a method and system for determining liquid gap spacing.
Background
In the production of the monocrystalline silicon by the czochralski method, the guide cylinder is used for controlling the flow form of protective gas (such as argon), weakening the temperature difference between the upper part and the lower part and reducing the influence of the gas flow on the growth of the monocrystalline silicon. The distance from the lower edge of the draft tube to the surface of the molten silicon (referred to herein as the gap) greatly affects the growth of the silicon single crystal. Therefore, accurate measurement of the liquid gap is required.
The temperature in the single crystal furnace is very high, the requirement on the cleanness of the environment in the single crystal furnace is high, and the existing material technology cannot support the direct measurement of the distance between liquid ports in the single crystal furnace. At present, all liquid port distance measuring methods can be divided into two methods, namely monocular distance measurement and laser distance measurement. The main method of monocular distance measurement is to measure the distance d between the lower edge of the guide cylinder and the edge of the reflection of the guide cylinder on the molten silicon liquid level, and according to the positive correlation between the distance d and the distance h from the lower edge of the guide cylinder to the molten silicon liquid level, a correction coefficient k is used, and the liquid port distance is estimated by a formula h ≈ d × k, and the representative method can be found in CN 112281208A; the main method of laser ranging is to emit a laser beam by a laser emitter, and calculate the time difference by receiving the reflected laser beam by a receiver to obtain the target distance, and the representative methods can be found in CN110552059A and CN 104005083A.
Monocular distance measurement is low in cost and generally poor in precision; the laser ranging has high cost and high precision. At present, no method can give consideration to both low cost and high precision.
Accordingly, there is a need for an improved method and system for determining liquid gap that is cost effective and highly accurate.
Disclosure of Invention
The invention aims to provide a solution for measuring liquid opening distance in a high-precision and low-cost mode by utilizing an existing industrial camera arranged on a single crystal furnace.
According to a first aspect of the present invention, there is provided a method of determining a liquid gap, the method comprising: acquiring a target image about the guide cylinder and its reflection by an imaging device, the target image showing an inner lower edge of the guide cylinder and the reflection of the inner lower edge of the guide cylinder present on a melt level; selecting a first sub-image and a second sub-image in the target image, wherein the first sub-image comprises a first end point and a third end point, and the second sub-image comprises a second end point and a fourth end point, wherein a distance between the first end point and the second end point defines a widest distance of an inner lower edge of the guide cylinder, and a distance between the third end point and the fourth end point defines a widest distance of a reflection of the inner lower edge of the guide cylinder; determining pixel coordinates of the first endpoint and the third endpoint and pixel coordinates of the second endpoint and the fourth endpoint in the first sub-image and the second sub-image and further in the target image; calculating a first pixel distance between the first end point and the second end point according to the pixel coordinates of the first end point and the second end point in the target image, and calculating a second pixel distance between the third end point and the fourth end point according to the pixel coordinates of the third end point and the fourth end point in the target image; and calculating the distance from the lower edge of the guide cylinder to the liquid level of the molten material according to at least the actual inner diameter of the lower edge of the guide cylinder, the first pixel distance, the second pixel distance and the parameters of a lens of the imaging device.
According to a preferred example of the method of the present invention, the method further comprises: calculating a third pixel distance from the first endpoint or the second endpoint to a center line of the target image and a fourth pixel distance from the third endpoint or the fourth endpoint to the center line of the target image according to the pixel coordinates of the first endpoint and the second endpoint in the target image, wherein the center line of the target image is parallel to an extending direction of a widest distance of an inner lower edge of the guide cylinder or an extending direction of a widest distance of a reflection of the inner lower edge; and the step of calculating the distance from the lower edge of the guide cylinder to the liquid level of the molten material further comprises the following steps: and calculating the distance from the lower edge of the guide cylinder to the liquid level of the molten material according to at least the actual inner diameter of the lower edge of the guide cylinder, the first pixel distance, the second pixel distance, the third pixel distance, the fourth pixel distance and the parameters of a lens of the imaging device.
According to an example of the method of the present invention, determining the pixel coordinates of the first and third end points and the pixel coordinates of the second and fourth end points in the first and second sub-images comprises: image processing the first and second sub-images to obtain a first set of pixel coordinates and a second set of pixel coordinates, respectively, wherein the first set of pixel coordinates includes pixel coordinates of all pixels in the first sub-image that are located between an inside lower edge of the guide cylinder and an inverted image of the inside lower edge of the guide cylinder, and the second set of pixel coordinates includes pixel coordinates of all pixels in the second sub-image that are located between the inside lower edge of the guide cylinder and the inverted image of the inside lower edge of the guide cylinder; and determining the pixel coordinates of the first endpoint and the third endpoint according to the first set of pixel coordinates, and determining the pixel coordinates of the second endpoint and the fourth endpoint according to the second set of pixel coordinates.
According to an example of the method of the present invention, said determining pixel coordinates of said first and third end points from said first set of pixel coordinates comprises: sorting all pixel coordinates in the first pixel coordinate set according to the size of an abscissa, so as to determine the pixel coordinate with the smallest abscissa in the first pixel coordinate set as the pixel coordinate of the first endpoint, wherein the direction of the abscissa is parallel to the extending direction of the widest distance of the lower edge of the guide cylinder or the extending direction of the widest distance of the reflection of the lower edge; dividing all pixel coordinates in the first pixel coordinate set into a plurality of first pixel coordinate subsets, wherein each pixel coordinate in the plurality of first pixel coordinate subsets has the same vertical coordinate, determining the pixel coordinate with the largest horizontal coordinate in each first pixel coordinate subset, and determining the pixel coordinate with the smallest horizontal coordinate in all the determined pixel coordinates with the largest horizontal coordinate as the pixel coordinate of a third endpoint; and/or, the determining pixel coordinates of the second endpoint and the fourth endpoint according to the second set of pixel coordinates comprises: sorting all pixel coordinates in the second pixel coordinate set according to the size of the abscissa so as to determine the pixel coordinate with the maximum abscissa in the second pixel coordinate set as the pixel coordinate of the second endpoint; and dividing all pixel coordinates in the second pixel coordinate set into a plurality of second pixel coordinate subsets, wherein each pixel coordinate in the plurality of second pixel coordinate subsets has the same vertical coordinate, determining the pixel coordinate with the smallest horizontal coordinate in each second pixel coordinate subset, and determining the pixel coordinate with the largest horizontal coordinate in all the determined pixel coordinates with the smallest horizontal coordinate as the pixel coordinate of a fourth endpoint.
According to an example of the method of the present invention, said image processing said first and second sub-images to obtain a first and second set of pixel coordinates, respectively, is performed by image splitting said first and second sub-images twice by the Otsu method.
According to a second aspect of the present invention there is provided a system for determining the distance between fluid ports, the system comprising: an imaging device configured to: acquiring a target image about the guide cylinder and its reflection, the target image showing an inner lower edge of the guide cylinder and the reflection of the inner lower edge of the guide cylinder present on the melt level; an image processing unit configured to: selecting a first sub-image and a second sub-image in the target image, wherein the first sub-image comprises a first end point and a third end point, and the second sub-image comprises a second end point and a fourth end point, wherein a distance between the first end point and the second end point defines a widest distance of an inner lower edge of the guide cylinder, and a distance between the third end point and the fourth end point defines a widest distance of a reflection of the inner lower edge of the guide cylinder; determining pixel coordinates of the first endpoint and the third endpoint and pixel coordinates of the second endpoint and the fourth endpoint in the first sub-image and the second sub-image and further in the target image; and a calculation unit configured to: calculating a first pixel distance between the first end point and the second end point according to the pixel coordinates of the first end point and the second end point in the target image, and calculating a second pixel distance between the third end point and the fourth end point according to the pixel coordinates of the third end point and the fourth end point in the target image; and calculating the distance from the lower edge of the guide cylinder to the liquid level of the molten material according to at least the actual inner diameter of the lower edge of the guide cylinder, the first pixel distance, the second pixel distance and the parameters of a lens of the imaging device.
According to a preferred example of the system of the present invention, the computing unit is further configured to: calculating a third pixel distance from the first endpoint or the second endpoint to a center line of the target image and a fourth pixel distance from the third endpoint or the fourth endpoint to the center line of the target image according to the pixel coordinates of the first endpoint and the second endpoint in the target image, wherein the center line of the target image is parallel to an extending direction of a widest distance of an inner lower edge of the guide cylinder or an extending direction of a widest distance of a reflection of the inner lower edge; and the step of calculating the distance from the lower edge of the guide cylinder to the liquid level of the molten material further comprises the following steps: and calculating the distance from the lower edge of the guide cylinder to the liquid level of the molten material according to at least the actual inner diameter of the lower edge of the guide cylinder, the first pixel distance, the second pixel distance, the third pixel distance, the fourth pixel distance and the parameters of a lens of the imaging device.
According to one example of the system of the present invention, determining the pixel coordinates of the first and third end points and the pixel coordinates of the second and fourth end points in the first and second sub-images comprises: image processing the first and second sub-images to obtain a first set of pixel coordinates and a second set of pixel coordinates, respectively, wherein the first set of pixel coordinates includes pixel coordinates of all pixels in the first sub-image that are located between an inside lower edge of the guide cylinder and an inverted image of the inside lower edge of the guide cylinder, and the second set of pixel coordinates includes pixel coordinates of all pixels in the second sub-image that are located between the inside lower edge of the guide cylinder and the inverted image of the inside lower edge of the guide cylinder; and determining the pixel coordinates of the first endpoint and the third endpoint according to the first set of pixel coordinates, and determining the pixel coordinates of the second endpoint and the fourth endpoint according to the second set of pixel coordinates.
According to one example of the system of the present invention, said determining pixel coordinates of said first and third end points from said first set of pixel coordinates comprises: sorting all pixel coordinates in the first pixel coordinate set according to the size of an abscissa, so as to determine the pixel coordinate with the smallest abscissa in the first pixel coordinate set as the pixel coordinate of the first endpoint, wherein the direction of the abscissa is parallel to the extending direction of the widest distance of the lower edge of the guide cylinder or the extending direction of the widest distance of the reflection of the lower edge; dividing all pixel coordinates in the first pixel coordinate set into a plurality of first pixel coordinate subsets, wherein each pixel coordinate in the plurality of first pixel coordinate subsets has the same vertical coordinate, determining the pixel coordinate with the largest horizontal coordinate in each first pixel coordinate subset, and determining the pixel coordinate with the smallest horizontal coordinate in all the determined pixel coordinates with the largest horizontal coordinate as the pixel coordinate of a third endpoint; and/or, the determining pixel coordinates of the second endpoint and the fourth endpoint according to the second set of pixel coordinates comprises: sorting all pixel coordinates in the second pixel coordinate set according to the size of the abscissa so as to determine the pixel coordinate with the maximum abscissa in the second pixel coordinate set as the pixel coordinate of the second endpoint; and dividing all pixel coordinates in the second pixel coordinate set into a plurality of second pixel coordinate subsets, wherein each pixel coordinate in the plurality of second pixel coordinate subsets has the same vertical coordinate, determining the pixel coordinate with the smallest horizontal coordinate in each second pixel coordinate subset, and determining the pixel coordinate with the largest horizontal coordinate in all the determined pixel coordinates with the smallest horizontal coordinate as the pixel coordinate of a fourth endpoint.
According to an example of the system of the present invention, said image processing said first and second sub-images to obtain a first and second set of pixel coordinates, respectively, is performed by image splitting said first and second sub-images twice by the Otsu method.
The solution of the invention greatly reduces the equipment cost by using the existing industrial camera which is beneficial to the single crystal furnace, on the premise of not needing additional more hardware, and meanwhile, the method which can be strictly proved is used for realizing accurate distance measurement.
Drawings
The invention will now be described by way of non-limiting example only with reference to the accompanying drawings, in which:
FIG. 1 shows a schematic structural view of a single crystal furnace according to an example of the present invention;
FIG. 2 shows a flow chart of a method of determining liquid gap distance according to the present invention;
FIG. 3 illustrates a system for determining liquid gap according to the present invention;
FIG. 4 shows a schematic view of the relative position of a draft tube and molten silicon according to an example of the invention;
FIG. 5A shows a perspective optical path diagram of camera imaging; FIG. 5B is the view of FIG. 5A rotated counterclockwise to the optical axis horizontal;
FIGS. 6A and 6B are side and top views, respectively, of FIG. 5B;
fig. 7 shows a target image acquired by the camera with respect to the guide cylinder and its reflection;
fig. 8 shows a first and a second sub-image and an image-processed first and second sub-image; and
fig. 9 shows a first target image acquired when the guide shell is in the first absolute position and a second target image acquired when the guide shell is in the second absolute position.
Detailed Description
In order to make the above and other features and advantages of the present invention more apparent, the present invention is further described below with reference to the accompanying drawings. It is understood that the specific examples set forth herein are for purposes of explanation only and are not intended to be limiting, as those skilled in the art will recognize.
Corresponding reference characters indicate corresponding parts throughout the several views of the drawings. Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention. Additionally, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments of the present invention.
Fig. 1 shows a schematic structural view of a single crystal furnace according to an example of the present invention. A single crystal furnace is an apparatus for melting polycrystalline materials such as polycrystalline silicon with a graphite heater in an inert gas (such as argon) atmosphere and then growing a dislocation-free single crystal by the czochralski method. Embodiments of the invention are described herein in the context of a single crystal furnace for growing single crystal silicon by the Czochralski method. It should be understood that the method and system of determining the liquid gap distance of the present invention may also be applied to determine the liquid level and the distance between draft tubes above the liquid level for any other industrial furnace, as long as the industrial furnace includes a melt level and a draft tube above the liquid level.
In fig. 1, there are shown a single crystal furnace 100, a camera 10, a guide cylinder 11, a seed crystal 12, a silicon rod 13, a crucible 14, molten silicon 15 in the crucible, a molten silicon level 16, and a lower edge 111 of the guide cylinder. The video camera 10 is configured to be able to acquire a target image on the guide cylinder and its reflection, and the video camera 10 may be any imaging device (for example, a monocular camera, a zoom camera, or a fixed focus camera) that is able to acquire a target image on the guide cylinder and its reflection. The lower edge 111 of the guide shell is circular in cross-section and has an inner diameter L (in millimeters).
In this context, the gap refers to the distance between the lower edge 111 of the guide shell and the surface 16 of the melt (e.g., molten silicon)A distance of
And (4) showing.
FIG. 2 is a flow chart of a method 200 of determining a fluid port spacing according to the present invention. As shown in FIG. 2, the method 200 includes steps 210 and 260.
In step 210, a target image of the guide cylinder and its reflection is acquired by an imaging device, the target image showing the inner lower edge of the guide cylinder and the reflection of the inner lower edge of the guide cylinder present on the melt level.
In step 220, a first sub-image and a second sub-image are selected from the target image, wherein the first sub-image includes a first end point and a third end point, and the second sub-image includes a second end point and a fourth end point, wherein a distance between the first end point and the second end point defines a widest distance of an inner lower edge of the guide cylinder, and a distance between the third end point and the fourth end point defines a widest distance of a reflection of the inner lower edge of the guide cylinder.
In step 230, the pixel coordinates of the first and third end points and the pixel coordinates of the second and fourth end points are determined in the first and second sub-images and further in the target image.
In step 240, a first pixel distance between the first end point and the second end point is calculated according to the pixel coordinates of the first end point and the second end point in the target image, and a second pixel distance between the third end point and the fourth end point is calculated according to the pixel coordinates of the third end point and the fourth end point in the target image.
In step 250, calculating a liquid opening distance from the lower edge of the guide cylinder to the liquid level of the molten material according to at least the actual inner diameter of the lower edge of the guide cylinder, the first pixel distance, the second pixel distance and parameters of a lens of the imaging device.
Fig. 3 illustrates a system 300 for determining liquid port spacing according to the present invention. As shown in fig. 3, the method 300 includes an imaging device 310, an image processing unit 320, and a computing unit 330. The imaging device 310, the image processing unit 320, and the computing unit 330 are communicatively coupled so that data can be transmitted via wired or wireless means.
The imaging device 310 is configured to:
acquiring a target image about the guide cylinder and its reflection, the target image showing the lower inner edge of the guide cylinder and the reflection of the lower inner edge of the guide cylinder present on the melt level.
The image processing unit 320 is configured to:
selecting a first sub-image and a second sub-image in the target image, wherein the first sub-image comprises a first end point and a third end point, and the second sub-image comprises a second end point and a fourth end point, wherein a distance between the first end point and the second end point defines a widest distance of an inner lower edge of the guide cylinder, and a distance between the third end point and the fourth end point defines a widest distance of a reflection of the inner lower edge of the guide cylinder;
determining the pixel coordinates of the first endpoint and the third endpoint and the pixel coordinates of the second endpoint and the fourth endpoint in the first sub-image and the second sub-image and further in the target image.
The calculation unit 330 is configured to:
calculating a first pixel distance between the first end point and the second end point according to the pixel coordinates of the first end point and the second end point in the target image, and calculating a second pixel distance between the third end point and the fourth end point according to the pixel coordinates of the third end point and the fourth end point in the target image; and
and calculating the distance from the lower edge of the guide cylinder to the liquid level of the molten material according to at least the actual inner diameter of the lower edge of the guide cylinder, the first pixel distance, the second pixel distance and the parameters of a lens of the imaging device.
Fig. 4 shows a schematic view of the relative position of a guide shell and molten silicon according to an example of the invention. In fig. 4 is shown the camera 10, the guide shell 11, the lower edge 111 of the guide shell, the position of the molten silicon level 16 and the reflection 17 of the lower edge of the guide shell present above the molten silicon level 16. According to the principle of planar mirror imaging, the reflection 17 of the lower edge of the guide cylinder is also circular and the inner diameter of the circular reflection 17 is the same as the inner diameter of the lower edge 111 of the guide cylinder. Furthermore, in fig. 4, an optical path diagram of the camera 10 imaging the inner diameter a of the lower edge 111 of the guide cylinder and the inner diameter B of the reflection 17 of the lower edge of the guide cylinder is shown in two sets of broken lines.
Fig. 5A shows a perspective optical path diagram of the image formed by the camera 10. Fig. 5A shows more detail than fig. 4. Fig. 5A shows the optical axis of the camera 10, which is perpendicular to the focal plane and the image plane of the camera 10. The focal plane and the image plane are not shown in fig. 5A, but are shown in fig. 6A and 6B. D in fig. 5A indicates the distance between the lower edge 111 of the guide shell and the reflection 17 of the lower edge of the guide shell. In fig. 5A, d denotes the distance between the inner diameter a of the lower edge 111 of the guide shell and the inner diameter B of the reflection 17 of the lower edge of the guide shell, in other words the distance between the inner diameter a and its mirror inner diameter B. According to the principle of planar mirror imaging, the liquid opening distance is in this context half the distance between the lower edge 111 of the guide cylinder and the reflection 17 of the lower edge of the guide cylinder, i.e. the distance between the two
Fig. 5B is a view when fig. 5A is rotated counterclockwise until the optical axis is horizontal. Such fig. 5B is shown for ease of description in conjunction with fig. 6A and 6B below.
Fig. 6A and 6B are a side view and a top view, respectively, of fig. 5B. Fig. 6A and 6B are shown in alignment for ease of understanding in connection with the description of fig. 6A and 6B below. In fig. 6A, the image and focal planes of the camera and the focal length f (in millimeters) of the camera are shown, which is the distance between the image and focal planes of the camera. Both inner diameter a and inner diameter B are shown as a point in the side view of fig. 6A. In fig. 6A, reference numeral 111 denotes a lower edge of the guide cylinder shown as one line in the side view, and reference numeral 17 denotes an inverted image of the lower edge of the guide cylinder shown as one line in the side view. Δ d shown in fig. 6A is the difference between the distance DB from the inner diameter B to the focal plane and the distance DA from the inner diameter a to the focal plane, i.e., Δ d — DB-DA. In practical cases, Δ d can be used as a measure of the double pitch of the liquid ports. This is because: due to the angle and distance relationship, the error between this measurement and the true port spacing Δ d is only in the millimeter. Marks Za and Zb shown in fig. 6A are a distance between the inner diameter a and the optical axis and a distance between the inner diameter B and the optical axis, respectively. The labels za and Zb shown in fig. 6A are the lengths (in millimeters) of za and Zb, respectively, in the image plane. The markers la and lb shown in fig. 6B are the lengths (in millimeters) of the inner diameter a and the inner diameter B on the image plane, respectively.
Based on the light path diagrams shown in fig. 6A and 6B and according to the triangular similarity relationship, the following equation can be obtained:
from equations (1) and (2), the following equations can be obtained:
Δ d may be used as an approximate measure of the liquid gap.
Further, based on the optical path diagrams shown in fig. 6A and 6B and according to the triangular similarity relationship, the following equation can also be obtained:
from equations (4) and (5), the following equations can be obtained:
where | Za-Zb | is an absolute value of a difference between a distance from the inner diameter a to the optical axis and a distance from the inner diameter B to the optical axis.
Referring to the small black right triangle shown in fig. 6A, the following equation can be derived according to the pythagorean theorem:
substituting equation (3) and equation (6) into equation (7) can result in the following equation:
in the actual calculation process, the actual lengths of la, lb, za and zb cannot be directly obtained from the image position, but the pixel lengths of corresponding la ', lb', za 'and zb' of la, lb, za and zb in the image coordinate system can only be obtained, and the following relations exist between the values of la, lb, za and zb and the values of la ', lb', za 'and zb':
la＝k*la′ (9)
lb＝k*lb′ (10)
za＝k*za′ (11)
zb＝k*zb′ (12)。
wherein the unit of la ', lb', za ', and zb' is a pixel; k is a ratio of a pixel size of a lens of the camera to an imaging resolution, and has a unit of millimeter/pixel.
Substituting equations (9) - (12) into equation (8) may result in the following equation:
due to the real distance between the liquid ports
The following equation is thus obtained:
in equation (14), the values of la ', lb', za ', and zb' may be acquired from the target image acquired by the camera through digital image processing. Further, for a fixed focus camera, where the focal length f is known and fixed, the value of f/k can be calculated from the parameters of the camera (specifically, the focal length, and the ratio of the pixel size of the lens of the camera to the imaging resolution); for a zoom camera, in which the focal length f is unknown and variable, the value of f/k needs to be calculated by a calculation method described later herein. A method of calculating a value of f/k for a zoom camera is presented herein.
A process of acquiring values of la ', lb', za ', and zb' from a target image acquired by a camera through digital image processing will now be described.
Fig. 7 shows an object image acquired by the camera with respect to the guide cylinder and its reflection. The target image shows the inner lower edge 51 of the guide cylinder and the reflection 53 of the inner lower edge 51 of the guide cylinder that is present above the molten silicon level. For ease of illustration, a "crescent-shaped" portion 52 between the inner lower edge 51 of the guide shell and its reflection 53, an image center line 510, and first and second sub-images 54, 55 taken in the target image are labeled in fig. 7, wherein the first sub-image 54 includes a first end point 56 and a third end point 58, and the second sub-image 55 includes a second end point 57 and a fourth end point 59, wherein the distance between the first end point 56 and the second end point 57 defines a widest distance 511 of the inner lower edge of the guide shell and the distance between the third end point 58 and the fourth end point 59 defines a widest distance 512 of the reflection 53 of the inner lower edge of the guide shell. The first sub-image 54 is defined by a first key zone (X1, Y1, W1, H1) and the second sub-image 55 is defined by a second key zone (X2, Y2, W2, H2), where W1 and H1 are the width and height, respectively, of the first key zone and W2 and H2 are the width and height, respectively, of the second key zone; the pixel coordinates of the pixel in the upper left corner of the first key zone are (X1, Y1) and the pixel coordinates of the pixel in the upper left corner of the second key zone are (X2, Y2).
Fig. 8 shows a first sub-image 54 and a second sub-image 55 and a first sub-image 54 'and a second sub-image 55' which have been image-processed. In addition, fig. 8 also shows the x-axis and y-axis directions of the pixel coordinates. The image-processed first sub-image 54 'and the image-processed second sub-image 55' are obtained by performing image segmentation twice on the first sub-image 54 and the second sub-image 55 by the ohq method.
A first set of pixel coordinates and a second set of pixel coordinates may be obtained from the first image-processed sub-image 54 'and the second image-processed sub-image 55', respectively, wherein the first set of pixel coordinates comprises the pixel coordinates of all pixels within the white portion of the first image-processed sub-image 54 '(i.e. the pixel coordinates of all pixels comprised in the first sub-image between the inner lower edge of the guide cylinder and the reflection of the inner lower edge of the guide cylinder) and the second set of pixel coordinates comprises the pixel coordinates of all pixels within the white portion of the second image-processed sub-image 55' (i.e. the pixel coordinates of all pixels comprised in the second sub-image between the inner lower edge of the guide cylinder and the reflection of the inner lower edge of the guide cylinder).
Then, pixel coordinates of the first end point and the third end point are determined according to the first set of pixel coordinates, and pixel coordinates of the second end point and the fourth end point are determined according to the second set of pixel coordinates.
Specifically, determining the pixel coordinates of the first endpoint and the third endpoint according to the first pixel coordinate set includes:
sorting all pixel coordinates in the first pixel coordinate set according to the size of an abscissa, so as to determine the pixel coordinate with the smallest abscissa in the first pixel coordinate set as the pixel coordinate of the first endpoint, wherein the direction of the abscissa is parallel to the extending direction of the widest distance of the lower edge of the guide cylinder or the extending direction of the widest distance of the reflection of the lower edge; and
dividing all pixel coordinates in the first pixel coordinate set into a plurality of first pixel coordinate subsets, wherein each pixel coordinate in the plurality of first pixel coordinate subsets has the same vertical coordinate, determining the pixel coordinate with the largest horizontal coordinate in each first pixel coordinate subset, and determining the pixel coordinate with the smallest horizontal coordinate in all the determined pixel coordinates with the largest horizontal coordinate as the pixel coordinate of a third endpoint.
Specifically, determining the pixel coordinates of the second endpoint and the fourth endpoint according to the second set of pixel coordinates includes:
sorting all pixel coordinates in the second pixel coordinate set according to the size of the abscissa so as to determine the pixel coordinate with the maximum abscissa in the second pixel coordinate set as the pixel coordinate of the second endpoint; and
dividing all pixel coordinates in the second pixel coordinate set into a plurality of second pixel coordinate subsets, wherein each pixel coordinate in the plurality of second pixel coordinate subsets has the same vertical coordinate, determining the pixel coordinate with the smallest horizontal coordinate in each second pixel coordinate subset, and determining the pixel coordinate with the largest horizontal coordinate in all the determined pixel coordinates with the smallest horizontal coordinate as the pixel coordinate of a fourth endpoint.
And mapping the determined pixel coordinates of the first endpoint, the second endpoint, the third endpoint and the fourth endpoint into the target image to obtain the mapped pixel coordinates of the first endpoint, the second endpoint, the third endpoint and the fourth endpoint. The pixel coordinate of the first endpoint is (X1, Y1), then the pixel coordinate mapped to the first endpoint in the target image is (X1+ X1, Y1+ Y1); the pixel coordinate of the second endpoint is (X2, Y2), then the pixel coordinate mapped to the second endpoint in the target image is (X2+ X2, Y2+ Y2); the pixel coordinate of the third endpoint is (X3, Y3), then the pixel coordinate mapped to the third endpoint in the target image is (X3+ X1, Y3+ Y1); the pixel coordinate of the fourth endpoint is (X4, Y4), and the pixel coordinate mapped to the fourth endpoint in the target image is (X4+ X2, Y4+ Y2).
From the pixel coordinates of the first end point (X1+ X1, Y1+ Y1), the pixel coordinates of the second end point (X2+ X2, Y2+ Y2), the pixel coordinates of the third end point (X3+ X1, Y3+ Y1), the pixel coordinates of the fourth end point (X4+ X2, Y4+ Y2), and the coordinates of the image center line (xc, yc), a calculation can be calculated
The desired values of la ', lb', za 'and zb'. The method comprises the following specific steps:
la′＝(x2+X2)-(x1+X1)
lb′＝(x4+X2)-(x3+X1)
za '═ Y1+ Y1) -yc or za' ═ Y2+ Y2) -yc
zb ═ Y3+ Y1) -yc or zb ═ Y4+ Y2) -yc.
In the case where the camera 10 is a fixed-focus camera, the value of f/k can be calculated from the focal length of the camera and the ratio of the pixel size of the lens of the camera to the imaging resolution. The values of f/k, la ', lb', za 'and zb' were substituted into equation (14) given above to calculate the liquid gap distance
In case the camera 10 is a zoom camera, the value of f/k needs to be calculated. A method of calculating a value of f/k is provided herein. The method of determining the value of f/k will be described below.
In the production process of growing the monocrystalline silicon by the Czochralski method, the guide cylinder is far away from the liquid level of the molten silicon in the material melting stage of melting the polycrystalline silicon from the solid state into the molten silicon. After the melting is finished, the guide cylinder is gradually lowered to be close to the liquid level of the molten silicon. During the process of gradually lowering the guide shell, the absolute position of the guide shell is known, wherein the absolute position of the guide shell refers to the position relative to the starting point of the guide shell. When the guide shell is in each absolute position, a corresponding target image may be acquired by the camera.
Fig. 9 shows a first target image 71 acquired when the guide shell is in the first absolute position and a second target image 72 acquired when the guide shell is in the second absolute position. When the guide shell is in the first absolute position, the guide shell moves a distance d1 relative to the initial position; when the guide shell is in the second absolute position, the guide shell is moved a distance d2 relative to its starting position. Therefore, d2-d1 are the moving distance of the guide shell. If the guide cylinder in the second absolute position is regarded as the reflection of the guide cylinder in the first absolute position, the distance d2-d1 that the guide cylinder moves is the distance d between the lower edge of the guide cylinder and the reflection of the lower edge of the guide cylinder, that is, d2-d 1. Further, according to the disclosed process of determining the first and second end points of the widest distance of the inner lower edge of the guide cylinder in the target image, the first and third pixel distances la 'and za' may be determined from the first target image 71. If the guide cylinder in the second absolute position is considered as an inverted image of the guide cylinder in the first absolute position, the inner lower edge of the guide cylinder in the second target image 72 is considered as an inverted image of the inner lower edge of the guide cylinder, and thus the second pixel distance lb 'and the fourth pixel distance zb' can be determined from the second target image 72.
From equation (13) given above, the following equation can be derived:
the values of la ', lb', za ', and zb' are determined and substituted into equation (15) to calculate the value of f/k.
In order to accurately calculate the f/k value, in practice, the guide shell is usually moved at a certain interval (e.g., 10 mm), and N sets of data (i.e., values of N sets of d, la ', lb', za ', and zb') are acquired within the movable range of the guide shell, and the N sets of data are acquired
The result of the individual calculations (i.e.,
f/k values) and the average of these calculation results is taken as the final f/k value, thereby reducing the influence of measurement errors and calculation errors.
As can be seen from the above description, the method of determining the liquid gap of the present invention is applicable to both fixed focus cameras and zoom cameras.
It will be understood that the specific features, operations and details described herein above with respect to the method of the present invention may be similarly applied to the system of the present invention, or vice versa. In addition, each step of the method of the present invention described above may be performed by a respective component or unit of the system of the present invention.
It should be understood that the various modules/units of the system of the present invention may be implemented in whole or in part by software, hardware, firmware, or a combination thereof. The modules/units may be embedded in the processor of the computer device in the form of hardware or firmware or independent from the processor, or may be stored in the memory of the computer device in the form of software for being called by the processor to execute the operations of the modules/units. Each of the modules/units may be implemented as a separate component or module, or two or more modules/units may be implemented as a single component or module.
In one example, a computer device is provided comprising a memory and a processor, the memory having stored thereon computer instructions executable by the processor, the computer instructions, when executed by the processor, instructing the processor to perform the steps of the method of the invention. The computer device may broadly be a server, a terminal, or any other electronic device having the necessary computing and/or processing capabilities. In one example, the computer device may include a processor, memory, a network interface, a communication interface, etc., connected by a system bus. The processor of the computer device may be used to provide the necessary computing, processing and/or control capabilities. The memory of the computer device may include non-volatile storage media and internal memory. An operating system, a computer program, and the like may be stored in or on the non-volatile storage medium. The internal memory may provide an environment for the operating system and the computer programs in the non-volatile storage medium to run. The network interface and the communication interface of the computer device may be used to connect and communicate with an external device through a network. The computer program, when executed by a processor, performs the steps of the above-described method for recharging a low-voltage battery of an electric vehicle.
The invention may be implemented as a computer-readable storage medium having stored thereon a computer program which, when executed by a processor, causes the steps of the method of the invention to be performed. In one example, the computer program is distributed over a plurality of computer devices or processors coupled over a network such that the computer program is stored, accessed, and executed by one or more computer devices or processors in a distributed fashion. A single method step/operation, or two or more method steps/operations, may be performed by a single computer device or processor or by two or more computer devices or processors. One or more method steps/operations may be performed by one or more computer devices or processors, and one or more other method steps/operations may be performed by one or more other computer devices or processors. One or more computer devices or processors may perform a single method step/operation, or perform two or more method steps/operations.
It will be appreciated by those of ordinary skill in the art that the steps of the method of the present invention may be directed to associated hardware, such as a computer device or a processor, for performing by a computer program that may be stored in a non-transitory computer readable storage medium and that when executed causes the steps of the method of the present invention to be performed. Any reference herein to memory, storage, databases, or other media may include non-volatile and/or volatile memory, as appropriate. Examples of non-volatile memory include read-only memory (ROM), programmable ROM (prom), electrically programmable ROM (eprom), electrically erasable programmable ROM (eeprom), flash memory, magnetic tape, floppy disk, magneto-optical data storage device, hard disk, solid state disk, and the like. Examples of volatile memory include Random Access Memory (RAM), external cache memory, and the like.
The respective technical features described above may be arbitrarily combined. Although not all possible combinations of features are described, any combination of features should be considered to be covered by the present specification as long as there is no contradiction between such combinations.
While the invention has been described in connection with examples, it is to be understood by those skilled in the art that the foregoing description and drawings are merely illustrative and not restrictive of the broad invention, and that this invention not be limited to the disclosed examples. Various modifications and variations are possible without departing from the spirit of the invention.
Claims (10)
1. A method of determining a liquid gap, comprising:
acquiring a target image about the guide cylinder and its reflection by an imaging device, the target image showing an inner lower edge of the guide cylinder and the reflection of the inner lower edge of the guide cylinder present on a melt level;
selecting a first sub-image and a second sub-image in the target image, wherein the first sub-image comprises a first end point and a third end point, and the second sub-image comprises a second end point and a fourth end point, wherein a distance between the first end point and the second end point defines a widest distance of an inner lower edge of the guide cylinder, and a distance between the third end point and the fourth end point defines a widest distance of a reflection of the inner lower edge of the guide cylinder;
determining pixel coordinates of the first endpoint and the third endpoint and pixel coordinates of the second endpoint and the fourth endpoint in the first sub-image and the second sub-image and further in the target image;
calculating a first pixel distance between the first end point and the second end point according to the pixel coordinates of the first end point and the second end point in the target image, and calculating a second pixel distance between the third end point and the fourth end point according to the pixel coordinates of the third end point and the fourth end point in the target image; and
and calculating the distance from the lower edge of the guide cylinder to the liquid level of the molten material according to at least the actual inner diameter of the lower edge of the guide cylinder, the first pixel distance, the second pixel distance and the parameters of a lens of the imaging device.
2. The method of determining liquid gap according to claim 1,
the method further comprises the following steps:
calculating a third pixel distance from the first endpoint or the second endpoint to a center line of the target image and a fourth pixel distance from the third endpoint or the fourth endpoint to the center line of the target image according to the pixel coordinates of the first endpoint and the second endpoint in the target image, wherein the center line of the target image is parallel to an extending direction of a widest distance of an inner lower edge of the guide cylinder or an extending direction of a widest distance of a reflection of the inner lower edge; and
the calculating the distance from the lower edge of the guide cylinder to the liquid level of the molten material further comprises: and calculating the distance from the lower edge of the guide cylinder to the liquid level of the molten material according to at least the actual inner diameter of the lower edge of the guide cylinder, the first pixel distance, the second pixel distance, the third pixel distance, the fourth pixel distance and the parameters of a lens of the imaging device.
3. The method of determining a liquid gap according to claim 1 or 2, wherein determining the pixel coordinates of the first end point and the third end point and the pixel coordinates of the second end point and the fourth end point in the first sub-image and the second sub-image comprises:
image processing the first and second sub-images to obtain a first set of pixel coordinates and a second set of pixel coordinates, respectively, wherein the first set of pixel coordinates includes pixel coordinates of all pixels in the first sub-image that are located between an inside lower edge of the guide cylinder and an inverted image of the inside lower edge of the guide cylinder, and the second set of pixel coordinates includes pixel coordinates of all pixels in the second sub-image that are located between the inside lower edge of the guide cylinder and the inverted image of the inside lower edge of the guide cylinder; and
determining pixel coordinates of the first end point and the third end point according to the first set of pixel coordinates, and determining pixel coordinates of the second end point and the fourth end point according to the second set of pixel coordinates.
4. The method of determining liquid gap according to claim 3,
the determining pixel coordinates of the first endpoint and the third endpoint from the first set of pixel coordinates comprises:
sorting all pixel coordinates in the first pixel coordinate set according to the size of an abscissa, so as to determine the pixel coordinate with the smallest abscissa in the first pixel coordinate set as the pixel coordinate of the first endpoint, wherein the direction of the abscissa is parallel to the extending direction of the widest distance of the lower edge of the guide cylinder or the extending direction of the widest distance of the reflection of the lower edge; and
dividing all pixel coordinates in the first pixel coordinate set into a plurality of first pixel coordinate subsets, wherein each pixel coordinate in the plurality of first pixel coordinate subsets has the same vertical coordinate, determining the pixel coordinate with the largest horizontal coordinate in each first pixel coordinate subset, and determining the pixel coordinate with the smallest horizontal coordinate in all the determined pixel coordinates with the largest horizontal coordinate as the pixel coordinate of a third endpoint; and/or the presence of a gas in the gas,
the determining pixel coordinates of the second endpoint and the fourth endpoint according to the second set of pixel coordinates comprises:
sorting all pixel coordinates in the second pixel coordinate set according to the size of the abscissa so as to determine the pixel coordinate with the maximum abscissa in the second pixel coordinate set as the pixel coordinate of the second endpoint; and
dividing all pixel coordinates in the second pixel coordinate set into a plurality of second pixel coordinate subsets, wherein each pixel coordinate in the plurality of second pixel coordinate subsets has the same vertical coordinate, determining the pixel coordinate with the smallest horizontal coordinate in each second pixel coordinate subset, and determining the pixel coordinate with the largest horizontal coordinate in all the determined pixel coordinates with the smallest horizontal coordinate as the pixel coordinate of a fourth endpoint.
5. The method according to claim 3, wherein the image processing of the first and second sub-images to obtain the first and second sets of pixel coordinates, respectively, is performed by image-splitting the first and second sub-images twice using Otsu's method.
6. A system for determining a liquid gap, comprising:
an imaging device configured to:
acquiring a target image about the guide cylinder and its reflection, the target image showing an inner lower edge of the guide cylinder and the reflection of the inner lower edge of the guide cylinder present on the melt level;
an image processing unit configured to:
selecting a first sub-image and a second sub-image in the target image, wherein the first sub-image comprises a first end point and a third end point, and the second sub-image comprises a second end point and a fourth end point, wherein a distance between the first end point and the second end point defines a widest distance of an inner lower edge of the guide cylinder, and a distance between the third end point and the fourth end point defines a widest distance of a reflection of the inner lower edge of the guide cylinder;
determining pixel coordinates of the first endpoint and the third endpoint and pixel coordinates of the second endpoint and the fourth endpoint in the first sub-image and the second sub-image and further in the target image; and
a computing unit configured to:
calculating a first pixel distance between the first end point and the second end point according to the pixel coordinates of the first end point and the second end point in the target image, and calculating a second pixel distance between the third end point and the fourth end point according to the pixel coordinates of the third end point and the fourth end point in the target image; and
and calculating the distance from the lower edge of the guide cylinder to the liquid level of the molten material according to at least the actual inner diameter of the lower edge of the guide cylinder, the first pixel distance, the second pixel distance and the parameters of a lens of the imaging device.
7. The system for determining liquid gap according to claim 6,
the computing unit is further configured to:
calculating a third pixel distance from the first endpoint or the second endpoint to a center line of the target image and a fourth pixel distance from the third endpoint or the fourth endpoint to the center line of the target image according to the pixel coordinates of the first endpoint and the second endpoint in the target image, wherein the center line of the target image is parallel to an extending direction of a widest distance of an inner lower edge of the guide cylinder or an extending direction of a widest distance of a reflection of the inner lower edge; and
the calculating the distance from the lower edge of the guide cylinder to the liquid level of the molten material further comprises: and calculating the distance from the lower edge of the guide cylinder to the liquid level of the molten material according to at least the actual inner diameter of the lower edge of the guide cylinder, the first pixel distance, the second pixel distance, the third pixel distance, the fourth pixel distance and the parameters of a lens of the imaging device.
8. The system for determining liquid port distances according to claim 6 or 7, wherein determining the pixel coordinates of the first end point and the third end point and the pixel coordinates of the second end point and the fourth end point in the first sub-image and the second sub-image comprises:
image processing the first and second sub-images to obtain a first set of pixel coordinates and a second set of pixel coordinates, respectively, wherein the first set of pixel coordinates includes pixel coordinates of all pixels in the first sub-image that are located between an inside lower edge of the guide cylinder and an inverted image of the inside lower edge of the guide cylinder, and the second set of pixel coordinates includes pixel coordinates of all pixels in the second sub-image that are located between the inside lower edge of the guide cylinder and the inverted image of the inside lower edge of the guide cylinder; and
determining pixel coordinates of the first end point and the third end point according to the first set of pixel coordinates, and determining pixel coordinates of the second end point and the fourth end point according to the second set of pixel coordinates.
9. The system for determining liquid gap according to claim 8,
the determining pixel coordinates of the first endpoint and the third endpoint from the first set of pixel coordinates comprises:
sorting all pixel coordinates in the first pixel coordinate set according to the size of an abscissa, so as to determine the pixel coordinate with the smallest abscissa in the first pixel coordinate set as the pixel coordinate of the first endpoint, wherein the direction of the abscissa is parallel to the extending direction of the widest distance of the lower edge of the guide cylinder or the extending direction of the widest distance of the reflection of the lower edge; and
dividing all pixel coordinates in the first pixel coordinate set into a plurality of first pixel coordinate subsets, wherein each pixel coordinate in the plurality of first pixel coordinate subsets has the same vertical coordinate, determining the pixel coordinate with the largest horizontal coordinate in each first pixel coordinate subset, and determining the pixel coordinate with the smallest horizontal coordinate in all the determined pixel coordinates with the largest horizontal coordinate as the pixel coordinate of a third endpoint; and/or the presence of a gas in the gas,
the determining pixel coordinates of the second endpoint and the fourth endpoint according to the second set of pixel coordinates comprises:
sorting all pixel coordinates in the second pixel coordinate set according to the size of the abscissa so as to determine the pixel coordinate with the maximum abscissa in the second pixel coordinate set as the pixel coordinate of the second endpoint; and
dividing all pixel coordinates in the second pixel coordinate set into a plurality of second pixel coordinate subsets, wherein each pixel coordinate in the plurality of second pixel coordinate subsets has the same vertical coordinate, determining the pixel coordinate with the smallest horizontal coordinate in each second pixel coordinate subset, and determining the pixel coordinate with the largest horizontal coordinate in all the determined pixel coordinates with the smallest horizontal coordinate as the pixel coordinate of a fourth endpoint.
10. The system for determining liquid gap according to claim 8, wherein the image processing of the first and second sub-images to obtain the first and second sets of pixel coordinates, respectively, is performed by image splitting the first and second sub-images twice by Otsu's method.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114046755A (en) * | 2021-11-16 | 2022-02-15 | 西安奕斯伟材料科技有限公司 | Device and method for obtaining real-time length of silicon rod pulled by Czochralski method and crystal pulling furnace |
| CN114399488A (en) * | 2022-01-12 | 2022-04-26 | 苏州天准科技股份有限公司 | Liquid gap monitoring method, storage medium, terminal and crystal pulling equipment |
| CN117604618A (en) * | 2023-11-24 | 2024-02-27 | 保定景欣电气有限公司 | Method and device for determining liquid mouth distance in crystal pulling process |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101748478A (en) * | 2008-12-15 | 2010-06-23 | 北京有色金属研究总院 | Method for measuring horizontal plane relative height of silicon melt in crucible |
| US20110316814A1 (en) * | 2010-06-28 | 2011-12-29 | Ming-Tsan Kao | Optical distance determination device, optical touch monitoring system and method for measuring distance of a touch point on an optical touch panel |
| CN207862479U (en) * | 2017-11-07 | 2018-09-14 | 宁夏隆基硅材料有限公司 | A kind of single crystal growing furnace is with automatic crystal pulling liquid mouth away from accurate-location device |
| CN111962145A (en) * | 2020-09-16 | 2020-11-20 | 西安奕斯伟硅片技术有限公司 | Method, device and equipment for detecting liquid level position of melt and computer storage medium |
| CN112281208A (en) * | 2019-07-22 | 2021-01-29 | 隆基绿能科技股份有限公司 | Liquid gap determining method and device and single crystal furnace |
-
2021
- 2021-04-28 CN CN202110468679.7A patent/CN113215653B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101748478A (en) * | 2008-12-15 | 2010-06-23 | 北京有色金属研究总院 | Method for measuring horizontal plane relative height of silicon melt in crucible |
| US20110316814A1 (en) * | 2010-06-28 | 2011-12-29 | Ming-Tsan Kao | Optical distance determination device, optical touch monitoring system and method for measuring distance of a touch point on an optical touch panel |
| CN207862479U (en) * | 2017-11-07 | 2018-09-14 | 宁夏隆基硅材料有限公司 | A kind of single crystal growing furnace is with automatic crystal pulling liquid mouth away from accurate-location device |
| CN112281208A (en) * | 2019-07-22 | 2021-01-29 | 隆基绿能科技股份有限公司 | Liquid gap determining method and device and single crystal furnace |
| CN111962145A (en) * | 2020-09-16 | 2020-11-20 | 西安奕斯伟硅片技术有限公司 | Method, device and equipment for detecting liquid level position of melt and computer storage medium |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114046755A (en) * | 2021-11-16 | 2022-02-15 | 西安奕斯伟材料科技有限公司 | Device and method for obtaining real-time length of silicon rod pulled by Czochralski method and crystal pulling furnace |
| CN114399488A (en) * | 2022-01-12 | 2022-04-26 | 苏州天准科技股份有限公司 | Liquid gap monitoring method, storage medium, terminal and crystal pulling equipment |
| CN114399488B (en) * | 2022-01-12 | 2022-11-25 | 苏州天准科技股份有限公司 | Liquid gap monitoring method, storage medium, terminal and crystal pulling equipment |
| CN117604618A (en) * | 2023-11-24 | 2024-02-27 | 保定景欣电气有限公司 | Method and device for determining liquid mouth distance in crystal pulling process |
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