WO2017161975A1 - Dispositif de détection d'épaisseur - Google Patents

Dispositif de détection d'épaisseur Download PDF

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Publication number
WO2017161975A1
WO2017161975A1 PCT/CN2017/073236 CN2017073236W WO2017161975A1 WO 2017161975 A1 WO2017161975 A1 WO 2017161975A1 CN 2017073236 W CN2017073236 W CN 2017073236W WO 2017161975 A1 WO2017161975 A1 WO 2017161975A1
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WO
WIPO (PCT)
Prior art keywords
electrode
detecting
common electrode
thickness
correction
Prior art date
Application number
PCT/CN2017/073236
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English (en)
Chinese (zh)
Inventor
姜利
张凯
Original Assignee
威海华菱光电股份有限公司
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Publication date
Application filed by 威海华菱光电股份有限公司 filed Critical 威海华菱光电股份有限公司
Publication of WO2017161975A1 publication Critical patent/WO2017161975A1/fr

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
    • G01B7/02—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring length, width or thickness
    • G01B7/06—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring length, width or thickness for measuring thickness

Definitions

  • the present invention relates to the field of electromechanical, and in particular to a thickness detecting device.
  • Thickness detecting devices have a wide range of applications, such as continuous thickness measurement of sheet-like articles such as paper, bills, plastic films, textile articles, etc., which are playing an increasingly important role in the production, testing, processing, recycling and the like.
  • the dielectric constant of the medium between the two electrodes is changed, so that the amount of charge induced on the detecting electrode is also With the change, the thickness of the detection object is different, the dielectric constant between the two electrodes is also different, and the amount of charge induced on the detection electrode is also different. Therefore, by detecting the magnitude of the electrical signal of the electrode, the thickness of the detection object is calculated. .
  • the thickness detecting device using the electrical characteristics in the prior art is subject to interference from the external environment, such as temperature, humidity, and noise.
  • the interference causes the detected electrical signal to change, and the accuracy of the detection is destroyed.
  • the present invention provides a thickness detecting device comprising: a common electrode; a detecting electrode corresponding to the common electrode and spaced apart from each other, a detecting channel formed between the detecting electrode and the common electrode; a correction electrode, and a common electrode Correspondingly and spaced apart from each other, the correction electrode is disposed outside the detection channel; the control unit is electrically connected to the common electrode, the detection electrode, and the correction electrode for correcting the output of the detection electrode according to the output of the correction electrode.
  • the electrical characteristics formed between the correction electrode and the common electrode are the same as those formed between the detection electrode and the common electrode.
  • the size of the correction electrode is the same as the size of the detection electrode, and the distance between the correction electrode and the common electrode is equal to the distance between the detection electrode and the common electrode.
  • correction electrode is disposed spaced apart from the detection electrode in a direction perpendicular to the extending direction of the detection channel.
  • the detecting electrodes are plural, and the plurality of detecting electrodes are arranged side by side, and the extending direction of the detecting channels is an arrangement direction of the plurality of detecting electrodes.
  • the thickness detecting device further includes a first protecting portion disposed outside the common electrode, and/or a second protecting portion disposed outside the detecting electrode.
  • the thickness detecting device further includes a second protecting portion disposed outside the detecting electrode and a third protecting portion disposed outside the correcting electrode, covering a thickness of the second protecting portion on the outer surface of the detecting electrode facing the common electrode The thickness of the third protective portion covering the outer surface of the correction electrode facing the common electrode is equal.
  • the thickness detecting device further includes: a first conductive portion disposed on an outer surface of the common electrode facing the detecting electrode; a second conductive portion disposed on an outer surface of the detecting electrode facing the common electrode; and a third conductive portion, And disposed on an outer surface of the correction electrode facing the common electrode; wherein the second conductive portion is the same size as the third conductive portion.
  • control unit includes a differential circuit, and the input ends of the differential circuits are electrically connected to the detection electrodes and the correction electrodes, respectively, and the difference circuit obtains an output value according to a difference between an output of the detection electrodes and an output of the correction electrodes.
  • control unit includes: a detection displacement output circuit, the input end is electrically connected to the detection electrode, and is used for outputting an electrical signal generated between the detection electrode and the common electrode; and correcting the displacement output circuit, the input end is electrically connected with the correction electrode, and is used for An electrical signal generated between the correction electrode and the common electrode is output.
  • the thickness detecting device performs thickness detection by changing electrical characteristics, that is, a detecting channel is formed between the common electrode and the detecting electrode, and the electrical property between the common electrode and the detecting electrode is changed from the detecting channel by the object to be detected.
  • the thickness of the object to be detected is obtained by the change in the electrical characteristics.
  • the thickness detecting device of the present invention is further provided with a correction electrode. Since the correction electrode is disposed outside the detection channel, the object to be detected does not pass through the correction electrode when passing through the detection channel. Therefore, when the detection electrode detects the object to be detected, the correction electrode is corrected.
  • the control unit can feedback the change of the electrical characteristics caused by the external interference, and the control unit corrects the signal detected by the detecting electrode by using the signal detected by the correcting electrode, thereby preventing the electrical signal reflecting the thickness of the object to be detected from being affected by external interference, and obtaining more authenticity. High thickness value.
  • Figure 1 shows a front view of an embodiment of a thickness detecting device according to the present invention
  • FIG. 2 is a schematic view showing the layout of the second substrate of FIG. 1;
  • Figure 3 is a view showing the logical relationship of the control portion of the thickness detecting device according to the present invention.
  • Fig. 4 shows a front view of another embodiment of a thickness detecting device according to the present invention.
  • 100 a common electrode; 201, a detecting electrode; 202, a correcting electrode; 11, a first frame; 12, a first substrate; 14, a first protection portion; 15, a first conductive portion; 21, a second frame; a second substrate; 23, a circuit component; 24, a second protection portion; 25, a second conductive portion; 26, a third conductive portion.
  • the thickness detecting device includes: a common electrode 100; and detecting electrodes 201 corresponding to the common electrode 100 and spaced apart from each other, and the detecting electrode 201 and the common electrode 100 Forming a detection channel; the correction electrode 202 is disposed corresponding to the common electrode 100 and spaced apart from each other, and the correction electrode 202 is disposed outside the detection channel; and the control portion is electrically connected to the common electrode 100, the detection electrode 201, and the correction electrode 202, It is used to correct the output of the detecting electrode 201 in accordance with the output of the correcting electrode 202.
  • the thickness detecting device of the present invention performs thickness detection using a change in electrical characteristics, that is, a detecting channel is formed between the common electrode 100 and the detecting electrode 201, and the electrical property between the common electrode 100 and the detecting electrode 201 is changed from the detecting channel by the object to be detected.
  • the thickness of the object to be detected is obtained by the change in the electrical characteristics.
  • the thickness detecting device of the present invention is further provided with a correction electrode 202. Since the correction electrode 202 is disposed outside the detection channel, the object to be detected does not pass through the correction electrode 202 when passing through the detection channel, so the detection electrode 201 is detected at the detection electrode 201.
  • the control unit corrects the signal detected by the detection electrode 201 by using the signal detected by the correction electrode 202, thereby avoiding the external signal that the electrical signal reflecting the thickness of the object to be detected is subjected to external interference. The effect is to get a true thickness value.
  • a plate capacitor is formed between the detecting electrode 201 and the common electrode 100, and a gap between the two is a medium of the capacitor.
  • the control portion is used to detect the detecting electrode 201 and the common A voltage signal between the electrodes 100.
  • the external interference can change the electrical characteristics of the plate capacitor formed by the detecting electrode 201 and the common electrode 100, such as temperature, humidity, vibration noise, electromagnetic noise, etc., and correct the plate capacitance formed between the electrode 202 and the common electrode 100.
  • the electrical characteristics formed between the correction electrode 202 and the common electrode 100 are the same as those formed between the detection electrode 201 and the common electrode 100.
  • the electrical characteristics formed between the correcting electrode 202 and the common electrode 100 are the same as those formed between the detecting electrode 201 and the common electrode 100, specifically It is to say that the performance of the plate capacitor formed between the correction electrode 202 and the common electrode 100 is the same as the performance of the plate capacitor formed between the detection electrode 201 and the common electrode 100. Under the same conditions, the output of the detection electrode 201 and the correction electrode 202 are output. The electrical signals are the same.
  • the size of the correction electrode 202 is the same as the size of the detection electrode 201, and the distance between the correction electrode 202 and the common electrode 100 is equal to the distance between the detection electrode 201 and the common electrode 100. Further, the materials of the correction electrode 202 and the detection electrode 201 are also the same.
  • the correction electrode 202 is disposed spaced apart from the detection electrode 201 in a direction perpendicular to the extending direction of the detection channel. Since the detection channel is formed between the detection electrode 201 and the common electrode 100, the correction electrode 202 is disposed offset from the detection channel.
  • the detection electrodes 201 are plural, and the plurality of detection electrodes 201 are arranged side by side, and the direction in which the detection channels extend is the arrangement direction of the plurality of detection electrodes 201.
  • the plurality of detecting electrodes 201 are arranged in a queue and form a detecting channel with the common electrode 100, and the correcting electrode 202 is spaced apart from the plurality of detecting electrodes 201 in a direction perpendicular to the detecting channel, thereby avoiding the detecting channel.
  • the correction electrode 202 is also disposed outside the end of the detection channel in the longitudinal direction of the detection channel. More specifically, the correction electrode 202 is disposed at an edge portion of the substrate in the longitudinal direction of the detection channel.
  • the end surface of the detecting electrode 201 or the common electrode 100 is in a bare arrangement, that is, the detecting electrode 201 or the outside of the common electrode 100 is not provided with a protective portion, such as the embodiment shown in FIG.
  • the thickness detecting device further includes a first protecting portion 14 disposed outside the common electrode 100, and/or a second protecting portion 24 disposed outside the detecting electrode 201.
  • a protection portion may be provided on the outer side of the electrode to prevent the object to be detected from abrading the electrode, and the accuracy of the thickness detection is improved.
  • a protective portion may be provided for the electrode that needs to be in contact with the object to be detected, or a protective portion may be provided for both electrodes.
  • a first protection portion 14 is disposed on the outer side of the common electrode 100, and a second protection portion 24 is disposed on the outer side of the detection electrode 201.
  • the first protection portion 14 and the second protection portion 24 may be It is a thin coating layer.
  • the thickness detecting device further includes a second protecting portion 24 disposed outside the detecting electrode 201 and a third protecting portion disposed outside the correcting electrode 202 covering the second surface of the detecting electrode 201 facing the outer surface of the common electrode 100
  • the thickness of the protection portion 24 is equal to the thickness of the third protection portion covering the outer surface of the correction electrode 202 facing the common electrode 100.
  • the correction electrode 202 does not wear out, since the detection electrode 201 is provided with the second protection portion 24, in order to make the correction electrode 202 and the detection electrode 201 the same, a third protection portion is also disposed outside the correction electrode 202, The thicknesses, materials, and the like of the third protection portion and the second protection portion 24 are the same. In the embodiment shown in Figure 4, the second protection portion 24 and the third protection portion are the same coating layer.
  • the thickness detecting device further includes: a first conductive portion 15 disposed on an outer surface of the common electrode 100 facing the detecting electrode 201; and a second conductive portion 25 disposed at the detecting electrode
  • the second conductive portion 26 is disposed on the outer surface of the correction electrode 202 facing the common electrode 100; wherein the second conductive portion 25 is the same size as the third conductive portion 26.
  • the detecting electrode 201 gives a more sensitive reaction, specifically to the plate capacitor, that is, the detecting electrode 201 and the common electrode 100.
  • the induced charge between the two can be rapidly accumulated so that the output voltage is rapidly increased correspondingly, thereby improving the sensitivity of the entire thickness detecting device.
  • the first conductive portion 15 is disposed on the end surface of the common electrode 100
  • the second conductive portion 25 is disposed on the end surface of the pole 201, wherein the conductive portion is a conductive film made of a highly conductive material, including gold or silver.
  • the third conductive portion 26 is also disposed on the end surface of the correction electrode 202, and The third conductive portion 26 and the second conductive portion 25 have the same specifications.
  • the protective portion is located outside the conductive portion.
  • the control portion includes a differential circuit
  • the input terminals of the differential circuit are electrically connected to the detecting electrode 201 and the correcting electrode 202, respectively, and the difference circuit is based on the difference between the output of the detecting electrode 201 and the output of the correcting electrode 202.
  • the value gets the output value.
  • the differential circuit also has an amplification function and is therefore a differential amplification circuit.
  • control unit further includes: a detection displacement output circuit, wherein the input end is electrically connected to the detection electrode 201, respectively, for outputting an electrical signal generated between the detection electrode 201 and the common electrode 100; the correction displacement output circuit, the input end It is electrically connected to the correction electrode 202 for outputting an electrical signal generated between the correction electrode 202 and the common electrode 100.
  • the input end of the detecting displacement output circuit is electrically connected to the output end of each detecting electrode 201, and the plurality of detecting electrodes 201 are sequentially arranged.
  • Forming the detection channel the more the number of electrodes in the unit length, the higher the resolution of the detecting device, and the function of detecting the displacement output circuit is to sequentially output the signals of the plurality of detecting electrodes 201 simultaneously outputted to facilitate the signal. deal with.
  • a circuit component 23 that is, a circuit component including a displacement detecting output circuit, a correction displacement output circuit, and a differential circuit, is further provided on the second substrate 22.
  • the charge can be induced on each of the detecting electrode 201 and the correcting electrode 202. It is assumed that the induced charge on the detecting electrode 201 is Q201, and the induced charge on the correcting electrode is Q202. At this time, the displacement output circuit is detected.
  • the voltage output signal is V201
  • the voltage output signal of the correction displacement output circuit is V202.
  • the output of such a differential circuit G is the magnification of differential amplification.
  • the amount of charge induced on the detecting electrode 201 and the correcting electrode 202 depends on the area of the electrode and the distance between the two electrodes from the common electrode 100, the amount of charge carried on the common electrode 100, and the relationship between the two electrodes and the common electrode 100. Dielectric constant. In the case where the structure is constant, the amount of charge induced on the detecting electrode 201 and the correcting electrode 202 is only related to the dielectric constant between the detecting electrode 201, the correcting electrode 202, and the common electrode 100. When the object to be detected passes through the detection channel, the dielectric constant of the medium between the detecting electrode 201 and the common electrode 100 is changed, and the amount of charge induced on the detecting electrode 201 is changed.
  • the displacement output is detected at this time.
  • Circuit voltage output When the object to be detected passes through the detection channel, since the correction electrode 202 is located outside the effective detection range, the dielectric constant of the medium between the correction electrode 202 and the common electrode 100 does not change, and the amount of charge induced on the correction electrode 202 is also The voltage output of the correction displacement output circuit does not change, and the voltage output of the displacement output circuit is corrected.
  • Differential circuit output It can be calculated that when the film to be tested passes, the change in the charge of the detecting electrode 201 is Therefore, the thickness of the film to be tested can be calculated by the change in the amount of charge on the electrode.
  • the sensitivity of the correction electrode 202 is the same as that of the detection electrode 201, and the same effect is felt on the detection electrode 201 and the correction electrode 202, and the amount of charge change is also the same, assuming a change in charge due to external disturbance.
  • Differential circuit output It is possible to calculate the change in the charge of the detecting electrode 201 when the object to be detected passes when the temperature, the humidity change, and the noise are affected. This value is the same as the calculated value without the influence of temperature, humidity and noise. Therefore, the correction electrode 202 and the differential circuit can eliminate the influence of the temperature, humidity and noise of the detecting electrode 201, and ensure the accuracy of the thickness detection.
  • the thickness detecting device further includes: a first substrate 12 and a second substrate 22 , the common electrode 100 is disposed on the first substrate 12 , and the detecting electrode 201 and the correcting electrode 202 It is disposed on the second substrate 22.
  • the thickness detecting device further includes: a first frame 11 and a second frame 21, wherein the first substrate 12 is disposed on the first frame 11; the second frame 21 is spaced apart from the first frame 11, the second substrate 22 is disposed on the second housing 21.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)

Abstract

La présente invention concerne un dispositif de détection d'épaisseur comprenant: une électrode commune (100); une électrode de détection (201) correspondant à l'électrode commune (100) et séparée de l'électrode commune, un canal de détection étant formé entre l'électrode de détection (201) et l'électrode commune (100); une électrode de compensation (202) correspondant à l'électrode commune (100) et séparée de l'électrode commune, l'électrode de compensation (202) étant disposée hors du canal de détection; et une partie commande connectée électriquement à l'électrode commune (100), l'électrode de détection (201) et l'électrode de compensation (202) et utilisée pour compenser une sortie de l'électrode de détection (201) en fonction d'une sortie de l'électrode de compensation (202). Comme l'électrode de compensation (202) est disposée hors du canal de détection et qu'un objet à détecter ne passe pas à travers l'électrode de compensation (202) lors de son passage à travers le canal de détection, quand l'électrode de détection (201) détecte l'objet à détecter, l'électrode de compensation (202) peut renvoyer un changement de caractéristique électrique dû à une interférence externe, et la partie commande utilise un signal détecté par l'électrode de compensation (202) pour compenser le signal détecté par l'électrode de détection (201), de façon à empêcher un signal électrique servant à refléter l'épaisseur de l'objet à détecter d'être influencé par une interférence externe et à obtenir une valeur d'épaisseur ayant une meilleure précision.
PCT/CN2017/073236 2016-03-25 2017-02-10 Dispositif de détection d'épaisseur WO2017161975A1 (fr)

Applications Claiming Priority (2)

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CN201610180183.9A CN105806206B (zh) 2016-03-25 2016-03-25 厚度检测装置
CN201610180183.9 2016-03-25

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CN105806206B (zh) * 2016-03-25 2019-01-08 威海华菱光电股份有限公司 厚度检测装置
CN106289039A (zh) * 2016-09-23 2017-01-04 威海华菱光电股份有限公司 薄膜厚度的检测装置
CN107063068A (zh) * 2017-02-28 2017-08-18 威海华菱光电股份有限公司 膜厚检测装置及方法
CN107063069A (zh) * 2017-02-28 2017-08-18 威海华菱光电股份有限公司 膜厚检测装置及方法
CN110352532B (zh) * 2017-06-02 2021-06-01 华为技术有限公司 一种检测可再充电电池鼓胀的方法和便携电子设备
CN110749298B (zh) * 2019-12-10 2021-03-12 滨州建筑工程施工图审查中心 一种建筑物外墙保温材料厚度检测装置
CN111504169A (zh) * 2020-04-20 2020-08-07 威海华菱光电股份有限公司 膜厚的检测装置
CN114383493B (zh) * 2022-02-28 2024-01-30 中国工程物理研究院总体工程研究所 一种非接触式金属表面非导电覆盖层厚度测量方法

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