An ice, water, dry state detection sensor

Abstract

This invention discloses a sensor for detecting ice, water, and dryness states, comprising a substrate, a first metal line, a second metal line, a third metal line disposed on the surface of the substrate, a variable capacitor, an interdigitated capacitor, and a planar inductor. One end of the variable capacitor is connected to one end of the planar inductor via the first metal line, and the other end of the planar inductor is connected to one end of the interdigitated capacitor via the second metal line. The other end of the interdigitated capacitor is connected to the other end of the variable capacitor via the third metal line. The capacitance value of the interdigitated capacitor changes with the different dielectric constants of the materials between the interdigitated fingers. Since the relative dielectric constants of ice, water, and dryness change at different frequencies, the capacitance value of the interdigitated capacitor also changes. Therefore, this sensor for detecting ice, water, and dryness states has advantages such as simple structure, high recognition rate, small size, and process compatibility.

Description

Technical Field

[0001] This invention belongs to the field of microelectronic device technology, and in particular relates to a sensor for detecting ice, water, and dry conditions. Background Technology

[0002] Ice, water, and dryness condition detection sensors are widely used in road condition monitoring systems, pipeline inspection, and other fields. With the trend towards miniaturization and micro-miniaturization, the development of ice, water, and dryness condition detection sensors has been rapid in recent years. Existing types of ice, water, and dryness condition detection sensors mainly include capacitive sensors, fiber optic sensors, and RT (resistance-temperature) sensors. Most of these employ sensor systems containing multiple sensors, thus exhibiting drawbacks such as high system integration difficulty and susceptibility to environmental factors affecting reliability and accuracy. In recent years, my country has made significant progress in the Internet of Things (IoT) field, and sensors, as an essential component of IoT, will inevitably see further research and development and promotion. In the field of ice, water, and dryness condition detection sensors, the application prospects in road and pipeline inspection are broad, but related design and research are still in a relatively basic stage. Under these circumstances, conducting research and design for the industrialization of ice, water, and dryness condition detection sensors is of great significance. Summary of the Invention

[0003] The purpose of this invention is to provide a sensor for detecting ice, water, and dry conditions, in order to solve the technical problems of traditional condition detection sensors being complex in structure, susceptible to interference, and non-reconfigurable.

[0004] To solve the above-mentioned technical problems, the specific technical solution of the present invention is as follows:

[0005] A sensor for detecting ice, water, and dry states includes a substrate, a first metal line, a second metal line, a third metal line, a variable capacitor, an interdigitated capacitor, and a planar inductor disposed on the surface of the substrate. One end of the variable capacitor is connected to one end of the planar inductor via the first metal line, and the other end of the planar inductor is connected to one end of the interdigitated capacitor via the second metal line. The other end of the interdigitated capacitor is connected to the other end of the variable capacitor via the third metal line. The capacitance value of the interdigitated capacitor changes with the different dielectric constants of the materials between the interdigitated fingers. Therefore, the capacitance value of the interdigitated capacitor will change according to the changes in the relative dielectric constants of the three states (ice, water, and dry) at different frequencies.

[0006] Furthermore, by adjusting the value of the variable capacitor, the resonant frequency of the resonant circuit composed of the variable capacitor, interdigitated capacitor, planar inductor, first metal line, second metal line, and third metal line is successively located in two ranges: 100kHz-10MHz and 1Hz-1kHz, thus exhibiting a reconfigurable structure.

[0007] Furthermore, when the resonant frequency of the resonant circuit is between 100kHz and 10MHz, two types of resonant frequencies will appear. When there is water accumulation, the capacitance of the interdigitated capacitor will increase, and the overall resonant frequency of the resonant circuit will be a relatively low frequency. When there is ice or dryness, the capacitance of the interdigitated capacitor will decrease, and the overall resonant frequency of the resonant circuit will be a relatively high frequency. Therefore, when the variable capacitor 1 is adjusted to a fixed value, the resonant frequency is detected. If the resonant frequency is too low, the detected state is determined to be water; if the resonant frequency is too high, the state is determined to be ice or dryness.

[0008] The capacitance of the variable capacitor is increased to a fixed value, so that the resonant frequency of the resonant circuit is between 1Hz and 1kHz. At this time, two resonant frequencies appear. When the circuit is frozen, the capacitance of the interdigitated capacitor increases, and the overall resonant frequency of the circuit is a relatively low frequency. When the circuit is dry, the capacitance of the interdigitated capacitor decreases, and the overall resonant frequency of the circuit is a relatively high frequency. Therefore, when the variable capacitor 1 is increased to a fixed value, the resonant frequency is detected. If the resonant frequency is low, the detection state is determined to be frozen; if the resonant frequency is high, the detection state is determined to be dry.

[0009] The present invention provides a sensor for detecting ice, water, and dryness states, which has the following advantages: The sensor differs from traditional sensors for detecting ice, water, and dryness states. Its main advantages are as follows: First, by reducing the value of the variable capacitor, the resonant frequency of the resonant circuit composed of the variable capacitor, interdigitated capacitor, and planar inductor is placed in the range of 100kHz-10MHz. Within this range, the relative permittivity of water differs significantly from that of ice or dryness, while the difference is smaller. By detecting the resonant frequency of the detection circuit, the state of water versus ice or dryness can be determined. Furthermore, by increasing the value of the variable capacitor, the resonant frequency is placed within the range of 1Hz. Within the z-1kHz range, the relative permittivity of ice and dryness differs significantly. By detecting the resonant frequency of the detection circuit, the two states—ice and dryness—can be distinguished. By adjusting the variable capacitor twice, the detection of ice, water, and dryness can be achieved. Therefore, this ice, water, and dryness state detection sensor has a simple structure, flexible design, and advantages such as high recognition rate and strong anti-interference capability. Secondly, this ice, water, and dryness state detection sensor adopts a resonant circuit structure, detecting the state by detecting the resonant frequency, exhibiting high output stability and high reliability. Thirdly, this ice, water, and dryness state detection sensor requires no special manufacturing process and is fully compatible with microelectronics processing technology, which is beneficial for achieving sensor miniaturization. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of the ice, water, and dry state detection sensor of the present invention.

[0011] Figure 2This is a schematic diagram showing the relationship between the relative permittivity of water (25℃), ice, and air and frequency;

[0012] The markings in the diagram are as follows: 1. Variable capacitor; 21. First metal line; 22. Second metal line; 23. Third metal line; 3. Planar inductor; 4. Interdigitated capacitor; 5. Substrate. Detailed Implementation

[0013] To better understand the purpose, structure, and function of this invention, the following detailed description of an ice, water, and dryness state detection sensor is provided in conjunction with the accompanying drawings.

[0014] like Figure 1 As shown, a sensor for detecting ice, water, and dry states includes a substrate 5, a first metal line 21, a second metal line 22, a third metal line 23, a variable capacitor 1, a planar inductor 3, and an interdigital capacitor 4. One end of the variable capacitor 1 is connected to one end of the planar inductor 3 via the first metal line 21, the other end of the planar inductor 3 is connected to one end of the interdigital capacitor 4 via the second metal line 22, and the other end of the interdigital capacitor 4 is connected to the other end of the variable capacitor 1 via the third metal line 23. The first metal line 21, the second metal line 22, the third metal line 23, the variable capacitor 1, the planar inductor 3, and the interdigital capacitor 4 are placed on the substrate 5.

[0015] like Figure 2 As shown, the horizontal axis represents frequency, and the vertical axis represents relative permittivity. The relative permittivity of ice and water changes with different frequencies, while the relative permittivity of air is 1 across the entire frequency range. In the frequency range of 1Hz-10MHz, the relative permittivity of water is 80, and it decreases above 10MHz. In the frequency range of 1Hz-1kHz, the relative permittivity of ice is 80, and it decreases above 1kHz.

[0016] The circuit formed by connecting the variable capacitor 1, the planar inductor 3, and the interdigital capacitor 4 through the first metal line 21, the second metal line 22, and the third metal line 23 is an LC resonant circuit. According to the formula... It can be seen that the inductance value is that of the planar inductor 3, and the capacitance value is that of the variable capacitor 1 and the interdigitated capacitor 4 connected in series. First, the capacitance of the variable capacitor 1 is reduced to a fixed value, so that the resonant frequency of the resonant circuit is between 100kHz and 10MHz. At this time, two possible resonant frequencies will appear. When there is water, because the relative permittivity of water is 80 in this frequency range, the capacitance of the interdigitated capacitor 4 will increase, and the overall resonant frequency of the resonant circuit will be a relatively low frequency. When there is ice or dryness, because the relative permittivity of ice and air is between 1 and 10 in this frequency range, the capacitance of the interdigitated capacitor 4 will decrease, and the overall resonant frequency of the resonant circuit will be a relatively high frequency. Therefore, when the variable capacitor 1 is reduced to a fixed value, the resonant frequency is detected. If the resonant frequency is too low, the detected state is determined to be water; if the resonant frequency is too high, the state is determined to be ice or dryness, and further detection of the state is required. Furthermore, by increasing the capacitance of variable capacitor 1 to a fixed value, the resonant frequency of the resonant circuit is determined to be between 1Hz and 1kHz. At this point, two possible resonant frequencies will also appear. In an icy state, because the relative permittivity of ice is 80 in this frequency range, the capacitance of interdigitated capacitor 4 will increase, resulting in a lower overall resonant frequency. In a dry state, because the relative permittivity of air is 1 in this frequency range, the capacitance of interdigitated capacitor 4 will decrease, resulting in a higher overall resonant frequency. Therefore, when variable capacitor 1 is increased to a fixed value, the resonant frequency is detected. If the resonant frequency is too low, the detection state is determined to be icy; if the resonant frequency is too high, the detection state is determined to be dry.

[0017] The ice, water, and dryness state detection sensor of this invention has a simple structure. The entire sensor can be fabricated using microelectronics technology, achieving a high level of structural dimensional accuracy and significantly reducing its size, which is beneficial for sensor miniaturization. This ice, water, and dryness state detection sensor employs a reconfigurable structure with a variable capacitor. By adjusting the resonant frequency through the variable capacitor, it achieves a high recognition rate for the three states of ice, water, and dryness. Furthermore, the ice, water, and dryness state detection sensor utilizes a resonant circuit detection system connected by a variable capacitor, a planar inductor, and interdigitated capacitors, giving it advantages such as flexible design, high recognition rate, fast detection speed, small size, and process compatibility.

[0018] The criteria for distinguishing whether something belongs to this structure are as follows:

[0019] (a) A resonant circuit structure including interdigital capacitors, variable capacitors, and planar inductors is adopted. Based on the principle that the capacitance of interdigital capacitors changes with the dielectric constant of the interdigital materials, the three states of ice, water, and dryness are transformed into changes in resonant frequency.

[0020] (b) A reconfigurable structure with variable capacitors is adopted, and the resonant frequency is adjusted by the variable capacitors to achieve high recognition rate detection of three states: ice, water and dryness.

[0021] A structure that meets both of the above conditions should be considered as a sensor for detecting the ice, water, and dry states of that structure.

[0022] It is understood that the present invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. Furthermore, under the teachings of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of the present invention.

Claims

1. A sensor for detecting ice, water, and dryness states, characterized in that, The system includes a substrate (5), a first metal line (21), a second metal line (22), a third metal line (23), a variable capacitor (1), an interdigital capacitor (4), and a planar inductor (3) disposed on the surface of the substrate (5); one end of the variable capacitor (1) is connected to one end of the planar inductor (3) through the first metal line (21), the other end of the planar inductor (3) is connected to one end of the interdigital capacitor (4) through the second metal line (22), and the other end of the interdigital capacitor (4) is connected to the other end of the variable capacitor (1) through the third metal line (23); the capacitance value of the interdigital capacitor (4) changes with the dielectric constant of the interdigital material, so the capacitance value of the interdigital capacitor (4) will change according to the change of the relative dielectric constant of the three states of ice, water, and dryness at different frequencies; By adjusting the capacitance value of the variable capacitor (1), the resonant frequency of the resonant circuit composed of the variable capacitor (1), interdigitated capacitor (4), planar inductor (3), first metal line (21), second metal line (22), and third metal line (23) is successively in the range of 100kHz-10MHz and 1Hz-1kHz, and it has a reconfigurable structure. When the resonant frequency of the resonant circuit is between 100kHz and 10MHz, two types of resonant frequencies will appear. When the circuit is in a waterlogged state, the capacitance of the interdigitated capacitor (4) will increase, and the overall resonant frequency of the resonant circuit will be a relatively low frequency. When the circuit is in a frozen or dry state, the capacitance of the interdigitated capacitor (4) will decrease, and the overall resonant frequency of the resonant circuit will be a relatively high frequency. Therefore, when the variable capacitor 1 is reduced to a fixed value, the resonant frequency is detected. When the resonant frequency is low, the detection state is determined to be water. When the resonant frequency is too high, the state is determined to be either ice or dry. The capacitance of the variable capacitor (1) is increased to a fixed value, so that the resonant frequency of the resonant circuit is between 1Hz and 1kHz. At this time, two resonant frequencies appear. When the circuit is frozen, the capacitance of the interdigitated capacitor (4) will increase, and the resonant frequency of the total resonant circuit will be a relatively small frequency. When the circuit is dry, the capacitance of the interdigitated capacitor (4) will decrease, and the resonant frequency of the total resonant circuit will be a relatively large frequency. Therefore, when the variable capacitor 1 is increased to a fixed value, the resonant frequency is detected. When the resonant frequency is low, the detection state is determined to be ice. When the resonant frequency is too high, the detection state is determined to be dry.

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