Sensor and electronic device

Abstract

To provide a sensor and an electronic device capable of improving detection accuracy.SOLUTION: According to an embodiment, the sensor includes an element unit and a circuit unit. The element unit includes a substrate including a substrate surface, a fixed unit fixed to the substrate surface, a movable unit supported by the fixed unit, and multiple fixed electrodes. The multiple fixed electrodes are fixed to the substrate surface and face the movable unit. The multiple fixed electrodes include first and second electrodes. The circuit unit includes first and second charge amplifiers. The first charge amplifier includes a first operational amplifier that has a first inverting input and a first non-inverting input. The first inverting input is electrically connected to the first electrode. The first non-inverting input is set to a first potential. The second charge amplifier includes a second operational amplifier having a second inverting input and a second non-inverting input. The second inverting input is electrically connected to the second electrode. The second non-inverting input is set to a second potential different from the first potential.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present invention relate to sensors and electronic devices.

Background Art

[0002] For example, there are sensors using MEMS (Micro Electro Mechanical Systems) elements etc. In sensors, improvement in accuracy is desired.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Embodiments provide a sensor and an electronic device capable of improving detection accuracy.

Means for Solving the Problems

[0005] According to an embodiment, the sensor includes an element unit and a circuit unit. The element unit includes a substrate including a substrate surface, a fixing portion fixed to the substrate surface, a movable portion supported by the fixing portion, and a plurality of fixed electrodes. A first gap is provided between the substrate surface and the movable portion. The plurality of fixed electrodes are fixed to the substrate surface and face the movable portion. The plurality of fixed electrodes include a first electrode and a second electrode. A first direction from the fixing portion to the first electrode is along a first plane along the substrate surface. A second direction from the fixing portion to the second electrode is along the first plane and is inclined with respect to the first direction. The circuit unit includes a first charge amplifier and a second charge amplifier. The first charge amplifier includes a first operational amplifier including a first inverting input and a first non-inverting input. The first inverting input is electrically connected to the first electrode. The first non-inverting input is set to a first potential. The second charge amplifier includes a second operational amplifier including a second inverting input and a second non-inverting input. The second inverting input is electrically connected to the second electrode. The second non-inverting input is set to a second potential different from the first potential. The circuit unit is configured to detect an angular velocity of the external force based on a first value based on a first output of the first charge amplifier and a second output of the second charge amplifier, which is a change in a vibration state of the movable portion due to the external force applied to the element unit.

Brief Description of Drawings

[0006]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0007] Hereinafter, each embodiment of the present invention will be described with reference to the drawings. The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the ratio of the sizes between parts, etc. are not necessarily the same as those in reality. Even when representing the same part, the dimensions and ratios may be represented differently in the drawings. In the present specification and each figure, the same reference numerals are given to the same elements as those described above with respect to the previously shown figures, and the detailed description will be omitted as appropriate.

[0008] (First Embodiment) FIG. 1 is a schematic diagram illustrating the sensor according to the first embodiment. FIGS. 2(a) and 2(b) are schematic diagrams illustrating a part of the sensor according to the first embodiment. FIG. 2(a) is a plan view. FIG. 2(b) is a cross-sectional view taken along line A1 - A2 of FIG. 2(a). As shown in FIG. 1, the sensor 110 according to the embodiment includes an element part 10E and a circuit part 70.

[0009] FIGS. 2(a) and 2(b) illustrate the element part 10E. The element part 10E includes a base body 10s, a fixing part 10F, a movable part 10M, and a plurality of fixed electrodes 50. The base body 10s includes a base body surface 10f.

[0010] The fixing part 10F is fixed to the base body surface 10f. The movable part 10M is supported by the fixing part 10F. A first gap G1 is provided between the base body surface 10f and the movable part 10M. The plurality of fixed electrodes 50 are fixed to the base body surface 10f. The plurality of fixed electrodes 50 face the movable part 10M. The movable part 10M is conductive.

[0011] As shown in Fig. 2(a), the plurality of fixed electrodes 50 includes, for example, a first electrode 51 and a second electrode 52. The plurality of fixed electrodes 50 may further include other electrodes such as a third electrode 53 and a fourth electrode 54. The first direction D1 from the fixing portion 10F to the first electrode 51 is along the first plane PL1. The first plane PL1 is along the substrate surface 10f. The second direction D2 from the fixing portion 10F to the second electrode 52 is along the first plane PL1. The second direction D2 is inclined with respect to the first direction D1.

[0012] The direction perpendicular to the substrate surface 10f is defined as the Z-axis direction. One direction perpendicular to the Z-axis direction is defined as the X-axis direction. The direction perpendicular to the Z-axis direction and the X-axis direction is defined as the Y-axis direction. The first plane PL1 is along the X-Y plane.

[0013] The movable portion 10M is provided, for example, between the fixing portion 10F and the first electrode 51, and between the fixing portion 10F and the second electrode 52. The movable portion 10M is provided, for example, between the fixing portion 10F and the third electrode 53, and between the fixing portion 10F and the fourth electrode 54.

[0014] The movable portion 10M is provided around the fixing portion 10F along the first plane PL1. At least a part of the movable portion 10M is annular. For example, the movable portion 10M includes a plurality of concentric annular portions 10n centered on the fixing portion 10F.

[0015] In this example, the movable portion 10M further includes a radial portion 10x. The radial portion 10x is continuous with at least two of the plurality of annular portions 10n. The radial portion 10x extends along a first radial direction Dx1 along the first plane PL1. The first radial direction Dx1 passes through the center 10c of the fixing portion 10F in the first plane PL1. The movable portion 10M of the element portion 10E is, for example, disk-shaped.

[0016] In the element section 10E, an alternating current signal (alternating voltage) is applied to at least one of the plurality of fixed electrodes 50. The movable section 10M vibrates due to the alternating current signal. When an external force is applied to the vibrating movable section 10M, the vibration state changes according to the external force. By detecting the change in the vibration state, the angular velocity of the external force is detected. The sensor 110 is, for example, a disk-type gyro sensor. In the sensor 110, the resonance state of the movable section 10M is utilized for detection. The sensor 110 is, for example, a disk resonance type gyro sensor.

[0017] The circuit section 70 can detect the vibration state of the movable section 10M. As shown in FIG. 1, the circuit section 70 includes a first charge amplifier 71 and a second charge amplifier 72. These charge amplifiers are, for example, sense amplifiers.

[0018] The first charge amplifier 71 includes a first operational amplifier 71A. The first operational amplifier 71A includes a first inverting input 71a and a first non-inverting input 71b. The first inverting input 71a is electrically connected to the first electrode 51. The first non-inverting input 71b is set to a first potential E1.

[0019] The second charge amplifier 72 includes a second operational amplifier 72A. The second operational amplifier 72A includes a second inverting input 72a and a second non-inverting input 72b. The second inverting input 72a is electrically connected to the second electrode 52. The second non-inverting input 72b is set to a second potential E2. The second potential E2 is different from the first potential E1.

[0020] The circuit section 70 is configured to detect the angular velocity of the external force by using a first value As1 based on the first output Va1 of the first charge amplifier 71 and the second output Va2 of the second charge amplifier 72, which is the change in the vibration state of the movable section 10M due to the external force applied to the element section 10E.

[0021] In an embodiment, the non-inverting inputs of the first operational amplifier 71A and the second operational amplifier 72A that function as sense amplifiers are set to different potentials from each other. By setting the two non-inverting inputs to different potentials from each other, different voltages are applied to the two electrodes. As a result, for example, correction of the vibration state becomes possible with different voltages. Thereby, high accuracy can be obtained. According to the embodiment, a sensor capable of improving detection accuracy can be provided.

[0022] As shown in FIG. 1, the circuit unit 70 may further include a processing circuit 73. The processing circuit 73 is configured to output a first ratio and a second ratio. The first ratio is the ratio (Va1 / E1) of the first output Va1 to the first potential E1. The second ratio is the ratio of the second output Va2 to the second potential E2. The first value As1 is, for example, a function of the first ratio and the second ratio. For example, the signal obtained from the first electrode 51 and the signal obtained from the second electrode 52 may be synchronously detected based on the frequency of the signals. For example, the phase angle φ with respect to the reference signal is obtained by synchronous detection. The function may include a cosine component and a sine component of the phase angle φ1 in the first direction D1 and a cosine component and a sine component of the phase angle φ2 in the second direction D2 (see FIG. 2).

[0023] In the embodiment, as described above, the two non-inverting inputs are set to different potentials (the first potential E1 or the second potential E2) from each other. At this time, the first output Va1 of the first operational amplifier 71A is corrected by the first potential E1. The second output Va2 of the second operational amplifier 72A is corrected by the second potential E2. By using the detection result (the first value As1) obtained from the corrected value, the target angular velocity can be appropriately detected.

[0024] As already described, the plurality of fixed electrodes 50 further include a third electrode 53 and a fourth electrode 54. As shown in FIG. 2(a), the third direction D3 from the fixing portion 10F to the third electrode 53 is along the first plane PL1. The fourth direction D4 from the fixing portion 10F to the fourth electrode 54 is along the first plane PL1. The fourth direction D4 intersects the third direction D3.

[0025] As shown in FIG. 1, the circuit unit 70 may further include a first circuit 75a. The first circuit 75a is configured to supply an AC signal Sig_A to at least one of the third electrode 53 and the fourth electrode 54 to vibrate the movable part 10M. In this example, the first circuit 75a supplies a first drive signal Vr1 to the third electrode 53. The first circuit 75a supplies a second drive signal Vr2 to the fourth electrode 54. The first drive signal Vr1 and the second drive signal Vr2 are included in the AC signal Sig_A.

[0026] The third electrode 53 and the fourth electrode 54 are drive electrodes. The first circuit 75a is a driver. Due to the first circuit 75a, the desired vibration occurs in the movable part 10M. A plurality of fixed electrodes 50 and the movable part 10M form a parallel electrode pair. Vibration is obtained by the electrostatic force in the parallel electrode pair including the third electrode 53 and the fourth electrode 54. A signal (voltage) based on the vibration is obtained by the electrostatic force in the parallel electrode pair including the first electrode 51 and the second electrode 52.

[0027] As shown in FIG. 1, the circuit unit 70 may further include a second circuit 75b. The second circuit 75b is configured to control the first circuit 75a so as to return the vibration state of the movable part 10M to the state when no external force is applied based on the first value As1. The second circuit 75b is, for example, a controller.

[0028] For example, in a first vibration state where no external force is applied to the element unit 10E, the movable part 10M vibrates along a first vibration direction. In a second vibration state where an external force is applied to the element unit 10E, the vibration state of the movable part 10M includes a component in a second vibration direction that intersects the first vibration direction. For example, the second vibration direction is perpendicular to the first vibration direction. These vibration directions may be any direction along the first plane PL1. The change in the vibration state due to the external force may be based on, for example, the Coriolis force.

[0029] For example, the circuit unit 70 adjusts the AC signal Sig_A so as to return the second oscillation state to the first oscillation state using the above-described first value As1 (a value based on the output from the sensor amplifier). For example, the circuit unit 70 (the second circuit 75b) detects the angular velocity based on a change in the AC signal Sig_A for adjustment.

[0030] The second circuit 75b may be capable of outputting a detection result signal Sig0 regarding the detected angular velocity.

[0031] The second circuit 75b may supply the above-described first potential E1 to the first non-inverting input 71b. The second circuit 75b may supply the above-described second potential E2 to the second non-inverting input 72b. The second circuit 75b may control the power supply circuit to cause the power supply circuit to supply the first potential E1 to the first non-inverting input 71b. The second circuit 75b may control the power supply circuit to cause the power supply circuit to supply the second potential E2 to the second non-inverting input 72b.

[0032] In an embodiment, the third direction D3 may be inclined with respect to the first direction D1. The fourth direction D4 may be inclined with respect to the third direction D3. [[ID=]14]

[0033] In one example of the embodiment, the first potential E1 is 1 V. The second potential E2 is 4 V. In one example, the second potential E2 is 1.5 times or more the first potential E1.

[0034] In an embodiment, for example, the ratio of the absolute value of the difference between the first potential E1 and the second potential E2 to the first potential E1 may be 0.1 or more. For example, the first potential E1 and the second potential E2 are positive. For example, the first potential E1 is lower than the second potential E2. For example, the first ratio (Va1 / E1) is higher than the second ratio (Va2 / E2).

[0035] The circuit unit 70 may be configured to vibrate the movable unit 10M along the first direction D1 when no external force is applied to the element unit 10E.

[0036] For example, a method of adjusting vibration characteristics by electrostatic force can be considered. In this case, nonlinearity is likely to occur in the vibration direction (the first vibration direction). In the vibration direction, the detection sensitivity may be low. On the other hand, in the angular velocity detection direction (the second vibration direction) orthogonal to the vibration direction, practical problems regarding nonlinearity are less likely to occur. In the direction orthogonal to the vibration direction (the angular velocity detection direction), it is preferable that the detection sensitivity is high. When the potential of the non-inverting input of the sense amplifier is high, the detection sensitivity becomes high.

[0037] In an embodiment, for example, the vibration direction is set to the direction of the electrode with a low potential. Thereby, high sensitivity is easily obtained in the detection of the angular velocity. The non-linearity of the vibration of the movable part 10M is suppressed, and high accuracy is easily obtained.

[0038] In an embodiment, the movable part 10M has a first resonance mode and a second resonance mode. The ratio of the absolute value of the difference between the first resonance frequency of the first resonance mode and the second resonance frequency of the second resonance mode to the first resonance frequency is 0.001 or less. For example, the resonance frequencies in two different directions are matched. The sensor 110 is, for example, a mode-matching gyro sensor.

[0039] For example, in a mode-matching gyro sensor, the asymmetry of the resonance frequency is adjusted by electrostatic force. In the adjustment by electrostatic force, the vibration state of the movable part 10M may be destabilized due to nonlinearity. Thereby, the detection accuracy of the angular velocity may deteriorate. In an embodiment, the potential of the non-inverting input of the sense amplifier is used for the adjustment. Thereby, the adjustment by electrostatic force and the optimization of the vibration direction can be implemented. The angular velocity can be detected with high accuracy.

[0040] In an embodiment, adjustment by electrostatic force may be further performed. As shown in FIG. 1, the plurality of fixed electrodes 50 may further include a fifth electrode 55 and a sixth electrode 56. As shown in FIG. 2(a), the fifth direction D5 from the fixing portion 10F to the fifth electrode 55 is along the first plane PL1. The sixth direction D6 from the fixing portion 10F to the sixth electrode 56 is along the first plane PL1. The sixth direction D6 intersects the fifth direction D5. In this example, the sixth direction D6 is inclined with respect to the fifth direction D5.

[0041] The circuit unit 70 is configured to supply a first signal Sg1 to at least one of the fifth electrode 55 and the sixth electrode 56 to adjust the vibration state. The first signal Sg1 is an adjustment voltage. In this example, the circuit unit 70 supplies a first adjustment voltage Vp1 to the fifth electrode 55. The circuit unit 70 supplies a second adjustment voltage Vp2 to the sixth electrode 56.

[0042] For example, the circuit unit 70 may be configured to supply a first signal Sg1 such that the difference between the vibration characteristics of the movable part 10M in the first direction D1 of the vibration state and the vibration characteristics in the first crossing direction Dc1 of the vibration state becomes small. The first crossing direction Dc1 intersects the first direction D1.

[0043] As shown in FIG. 1, the plurality of fixed electrodes 50 may include a fifth electrode 55, a sixth electrode 56, a seventh electrode 57, and an eighth electrode 58. As shown in FIG. 2(a), the fifth direction D5 from the fixing portion 10F to the fifth electrode 55 is along the first plane PL1. The sixth direction D6 from the fixing portion 10F to the sixth electrode 56 is along the first plane PL1 and intersects the fifth direction D5. The seventh direction D7 from the fixing portion 10F to the seventh electrode 57 is along the first plane PL1. The eighth direction D8 from the fixing portion 10F to the eighth electrode 58 is along the first plane PL1 and intersects the seventh direction D7.

[0044] The circuit unit 70 may be configured to supply the first signal Sg1 to at least one of the fifth electrode 55, the sixth electrode 56, the seventh electrode 57, and the eighth electrode 58 to adjust the vibration state of the movable unit 10M. In this example, the circuit unit 70 supplies the first adjustment voltage Vp1 to the fifth electrode 55. The circuit unit 70 supplies the second adjustment voltage Vp2 to the sixth electrode 56. The circuit unit 70 supplies the third adjustment voltage Vp3 to the seventh electrode 57. The circuit unit 70 supplies the fourth adjustment voltage Vp4 to the eighth electrode 58.

[0045] The first signal Sg1 (the first adjustment voltage Vp1, the second adjustment voltage Vp2, the third adjustment voltage Vp3, and the fourth adjustment voltage Vp4) may be supplied from the second circuit 75b. Electrostatic tuning is performed by these adjustment voltages.

[0046] The circuit unit 70 may be configured to supply the first signal Sg1 such that the difference between the vibration characteristics in the first direction D1 of the vibration state and the vibration characteristics in the first crossing direction Dc1 of the vibration state becomes small. The first crossing direction Dc1 intersects the first direction D1 along the first plane PL1.

[0047] In the embodiment, for example, the bias stability is improved by electrostatic tuning and optimization of the vibration direction.

[0048] FIG. 3 is a graph illustrating the characteristics of the sensor. FIG. 3 illustrates the characteristics of the sensor 119 of the reference example and the characteristics of the sensor 110 according to the embodiment. In the sensor 119, the first non-inverting input 71b and the second non-inverting input 72b are set to the same potential. The horizontal axis of these figures is time τ (s). The vertical axis of these figures is the Allan variance AD (dps: degrees per second). It is preferable that the Allan variance AD is small. As shown in FIG. 3, in the region where the time τ is long, the Allan variance AD in the sensor 110 is smaller than the Allan variance AD in the sensor 119. High-stability detection is possible in the sensor 110.

[0049] (Second Embodiment) The second embodiment relates to an electronic device. FIG. 4 is a schematic diagram illustrating an electronic device according to the second embodiment. As shown in FIG. 4, the electronic device 310 according to the embodiment includes the sensor according to the first embodiment (for example, the sensor 110) and the circuit control unit 170. The circuit control unit 170 can control the circuit 180 based on the signal S1 obtained from the sensor. The circuit 180 is, for example, a control circuit of the driving device 185 or the like. According to the embodiment, for example, a circuit 180 for controlling the driving device 185 or the like can be controlled with high precision.

[0050] As shown in FIG. 4, the sensor system 210 according to the embodiment includes the sensor according to the first embodiment (for example, the sensor 110) and the detection target member 81. The sensor 110 is fixed to the detection target member 81. The sensor 110 can detect the signal of the detection target member 81.

[0051] FIGS. 5(a) to 5(h) are schematic diagrams illustrating applications of the electronic device according to the embodiment. As shown in FIG. 5(a), the electronic device 310 may be at least a part of a robot. As shown in FIG. 5(b), the electronic device 310 may be at least a part of a machine robot provided in a manufacturing factory or the like. As shown in FIG. 5(c), the electronic device 310 may be at least a part of an automatic guided vehicle in a factory or the like. As shown in FIG. 5(d), the electronic device 310 may be at least a part of a drone (unmanned aerial vehicle). As shown in FIG. 5(e), the electronic device 310 may be at least a part of an airplane. As shown in FIG. 5(f), the electronic device 310 may be at least a part of a ship. As shown in FIG. 5(g), the electronic device 310 may be at least a part of a submarine. As shown in FIG. 5(h), the electronic device 310 may be at least a part of an automobile. The electronic device 310 may include, for example, at least one of a robot and a moving body.

[0052] FIGS. 6(a) and 6(b) are schematic diagrams illustrating applications of the sensor according to the embodiment. As shown in FIG. 6(a), the sensor 430 according to the embodiment includes the sensor according to the first embodiment and the transceiver unit 420. In the example of FIG. 6(a), the sensor 110 is depicted as the sensor. The transceiver unit 420 can transmit the signal obtained from the sensor 110 by, for example, at least one of wireless and wired methods. The sensor 430 is provided, for example, on the slope surface 410 such as the road 400. The sensor 430 can monitor, for example, the state of a facility (such as infrastructure). The sensor 430 may be, for example, a state monitoring device.

[0053] For example, the sensor 430 can detect with high precision a change in the state of the slope surface 410 of the road 400. The change in the state of the slope surface 410 includes, for example, at least one of a change in the inclination angle and a change in the vibration state. The signal (inspection result) obtained from the sensor 110 is transmitted by the transceiver unit 420. The state of a facility (such as infrastructure) can be monitored, for example, continuously.

[0054] As shown in FIG. 6(b), the sensor 430 is provided, for example, on a part of the bridge 460. The bridge 460 is provided over the river 470. For example, the bridge 460 includes at least one of the main girder 450 and the bridge pier 440. The sensor 430 is provided on at least one of the main girder 450 and the bridge pier 440. For example, due to deterioration or the like, the angle of at least one of the main girder 450 and the bridge pier 440 may change. For example, the vibration state may change in at least one of the main girder 450 and the bridge pier 440. These changes are detected with high precision by the sensor 430. The detection result can be transmitted by the transceiver unit 420 to any location. Abnormalities can be effectively detected.

[0055] The embodiment may include the following technical solutions. (Technical Solution 1) A substrate including a substrate surface, A fixing portion fixed to the substrate surface, A movable portion supported by the fixing portion, wherein a first gap is provided between the substrate surface and the movable portion, and the movable portion A plurality of fixed electrodes fixed to the base surface and facing the movable part, An element part including, A circuit part, Comprising, The plurality of fixed electrodes include a first electrode and a second electrode, The first direction from the fixed part to the first electrode is along a first plane along the base surface, The second direction from the fixed part to the second electrode is along the first plane and inclined with respect to the first direction, The circuit part includes a first charge amplifier and a second charge amplifier, The first charge amplifier includes a first operational amplifier including a first inverting input and a first non-inverting input, The first inverting input is electrically connected to the first electrode, The first non-inverting input is set to a first potential, The second charge amplifier includes a second operational amplifier including a second inverting input and a second non-inverting input, The second inverting input is electrically connected to the second electrode, The second non-inverting input is set to a second potential different from the first potential, The circuit part is configured to detect the angular velocity of the external force using a first value based on the first output of the first charge amplifier and the second output of the second charge amplifier for a change in the vibration state of the movable part due to the external force applied to the element part. A sensor.

[0056] (Technical solution 2) The circuit part further includes a processing circuit, The processing circuit is configured to output a first ratio and a second ratio, The first ratio is a ratio of the first output to the first potential, The second ratio is a ratio of the second output to the second potential, The first value is a function of the first ratio and the second ratio. The sensor according to Technical Solution 1.

[0057] (Technical solution 3) The plurality of fixed electrodes further includes a third electrode and a fourth electrode, A third direction from the fixed portion to the third electrode is along the first plane, A fourth direction from the fixed portion to the fourth electrode is along the first plane and intersects the third direction, The circuit portion further includes a first circuit, The first circuit is configured to supply an alternating current signal to at least one of the third electrode and the fourth electrode to vibrate the movable portion, and is the sensor according to Technical Solution 2.

[0058] (Technical Solution 4) The circuit portion further includes a second circuit, The second circuit is configured to control the first circuit so as to return the vibration state based on the first value when no external force is applied, and is the sensor according to Technical Solution 3.

[0059] (Technical Solution 5) In a first vibration state where no external force is applied to the element portion, the movable portion vibrates along a first vibration direction, In a second vibration state where the external force is applied to the element portion, the vibration state includes a component in a second vibration direction intersecting the first vibration direction, The circuit portion adjusts the alternating current signal so as to return the second vibration state to the first vibration state by using the first value, and is the sensor according to Technical Solution 3.

[0060] (Technical Solution 6) The circuit portion detects the angular velocity based on a change in the alternating current signal for the adjustment, and is the sensor according to Technical Solution 5.

[0061] (Technical Solution 7) The movable portion is provided between the fixed portion and the first electrode, between the fixed portion and the second electrode, between the fixed portion and the third electrode, and between the fixed portion and the fourth electrode, and is the sensor according to any one of Technical Solutions 3 to 6.

[0062] (Technical Solution 8) The movable part is a sensor according to Technical Proposal 7 provided around the fixed part along the first plane.

[0063] (Technical Proposal 9) The movable part is a sensor according to any one of Technical Proposals 1 to 6, including a plurality of concentric annular parts centered on the fixed part.

[0064] (Technical Proposal 10) The movable part includes a radial part continuous with at least two of the plurality of annular parts, The radial part extends along a first radial direction along the first plane, The first radial direction passes through the center of the fixed part in the first plane, and is a sensor according to Technical Proposal 9.

[0065] (Technical Proposal 11) The movable part has a first resonance mode and a second resonance mode, For a sensor according to any one of Technical Proposals 1 to 10, the ratio of the absolute value of the difference between the first resonance frequency of the first resonance mode and the second resonance frequency of the second resonance mode to the first resonance frequency is 0.001 or less.

[0066] (Technical Proposal 12) For a sensor according to any one of Technical Proposals 1 to 11, the ratio of the absolute value of the difference between the first potential and the second potential to the first potential is 0.1 or more.

[0067] (Technical Proposal 13) For a sensor according to any one of Technical Proposals 1 to 12, the circuit part is configured to vibrate the movable part along the first direction when no external force is applied to the element part.

[0068] (Technical Proposal 14) The first potential and the second potential are positive, The first potential is lower than the second potential, For a sensor according to any one of Technical Proposals 2 to 10, the first ratio is higher than the second ratio.

[0069] (Technical Solution 15) The third direction is inclined with respect to the first direction, The fourth direction is inclined with respect to the third direction, and the sensor according to any one of Technical Solutions 3 to 10.

[0070] (Technical Solution 16) The plurality of fixed electrodes further includes a fifth electrode and a sixth electrode, The fifth direction from the fixed portion to the fifth electrode is along the first plane, The sixth direction from the fixed portion to the sixth electrode is along the first plane and intersects the fifth direction, The circuit portion is configured to supply a first signal to at least one of the fifth electrode and the sixth electrode to adjust the vibration state, and the sensor according to any one of Technical Solutions 3 to 10.

[0071] (Technical Solution 17) The circuit portion is configured to supply the first signal such that the difference between the vibration characteristics in the first direction of the vibration state and the vibration characteristics in the first intersection direction of the vibration state is small, and the first intersection direction intersects the first direction along the first plane, and the sensor according to Technical Solution 16.

[0072] (Technical Solution 18) The plurality of fixed electrodes further includes a fifth electrode, a sixth electrode, a seventh electrode, and an eighth electrode, The fifth direction from the fixed portion to the fifth electrode is along the first plane, The sixth direction from the fixed portion to the sixth electrode is along the first plane and intersects the fifth direction, The seventh direction from the fixed portion to the seventh electrode is along the first plane, The eighth direction from the fixed portion to the eighth electrode is along the first plane and intersects the seventh direction, The circuit portion is configured to supply a first signal to at least one of the fifth electrode, the sixth electrode, the seventh electrode, and the eighth electrode to adjust the vibration state, and the sensor according to any one of Technical Solutions 3 to 10.

[0073] (Technical Proposal 19) The circuit unit is configured to supply the first signal such that the difference between the vibration characteristics in the first direction of the vibration state and the vibration characteristics in the first cross direction of the vibration state is small, and the first cross direction intersects the first direction along the first plane, and is the sensor according to Technical Proposal 18.

[0074] (Technical Proposal 20) The sensor according to any one of Technical Proposals 1 to 19, a circuit control unit capable of controlling a circuit based on a signal obtained from the sensor, and an electronic device provided therewith.

[0075] According to the embodiment, a sensor and an electronic device capable of improving detection accuracy can be provided.

[0076] As described above, the embodiments of the present invention have been described with reference to specific examples. However, the present invention is not limited to these specific examples. For example, regarding the specific configurations of each element such as the element unit, the substrate, the fixing unit, the movable unit, the fixed electrode, and the circuit unit included in the sensor, the present invention can be similarly implemented by appropriately selecting from the range known to those skilled in the art, and as long as the same effects can be obtained, it is included in the scope of the present invention.

[0077] In addition, a combination of any two or more elements of each specific example within a technically possible range is also included in the scope of the present invention as long as it includes the gist of the present invention.

[0078] In addition, based on the sensor described above as an embodiment of the present invention, all sensors that can be appropriately designed and modified by those skilled in the art also belong to the scope of the present invention as long as they include the gist of the present invention.

[0079] In addition, within the scope of the idea of the present invention, those skilled in the art can conceive various modification examples and correction examples, and it is understood that those modification examples and correction examples also belong to the scope of the present invention.

[0080] Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

Explanation of Reference Numerals

[0081] 10E: Element part, 10F: Fixed part, 10M: Movable part, 10c: Center, 10f: Substrate surface, 10n: Annular part, 10s: Substrate, 10x: Radiation part, 50: Fixed electrode, 51 - 58: First - eighth electrodes, 70: Circuit part, 71, 72: First, second charge amplifiers, 71A, 72A: First, second operation amplifiers, 71a, 72a: First, second inverting inputs, 71b, 72b: First, second non - inverting inputs, 73: Processing circuit, 75a: First circuit, 75b: Second circuit, 81: Detection target member, 110, 119: Sensors, 170: Circuit control part, 180: Circuit, 185: Driving device, 210: Sensor system, 310: Electronic device, 400: Road, 410: Slope surface, 420: Transceiving part, 430: Sensor, 440: Pier, 450: Main girder, 460: Bridge, 470: River, As1: First value, D1 - D8: First - eighth directions, Dc1: First intersection direction, Dx1: First radiation direction, E1, E2: First, second potentials, G1: First gap, PL1: First plane, S1: Signal, Sg1: First signal, Sig0: Detection result signal, Sig_A: Alternating current signal, Va1, Va2: First, second outputs, Vp1 - Vp4: First - fourth adjustment voltages, Vr1, Vr2: First, second driving signals

Claims

1. A substrate including a substrate surface, A fixing portion fixed to the substrate surface, A movable portion supported by the fixing portion, wherein a first gap is provided between the substrate surface and the movable portion, and the movable portion, A plurality of fixed electrodes fixed to the substrate surface and facing the movable portion, An element portion including the above, A circuit portion, Comprising, The plurality of fixed electrodes include a first electrode and a second electrode, The first direction from the fixing portion to the first electrode is along a first plane along the substrate surface, The second direction from the fixing portion to the second electrode is along the first plane and is inclined with respect to the first direction, The circuit portion includes a first charge amplifier and a second charge amplifier, The first charge amplifier includes a first operational amplifier including a first inverting input and a first non-inverting input, The first inverting input is electrically connected to the first electrode, The first non-inverting input is set to a first potential, The second charge amplifier includes a second operational amplifier including a second inverting input and a second non-inverting input, The second inverting input is electrically connected to the second electrode, The second non-inverting input is set to a second potential different from the first potential, The circuit portion is configured to detect the angular velocity of the external force based on a first value based on the first output of the first charge amplifier and the second output of the second charge amplifier for a change in the external force applied to the element portion due to the vibration state of the movable portion. Sensor.

2. The circuit portion further includes a processing circuit, The processing circuit is configured to output a first ratio and a second ratio, The first ratio is a ratio of the first output to the first potential, The second ratio is a ratio of the second output to the second potential, The first value is a function of the first ratio and the second ratio. The sensor according to claim 1.

3. The plurality of fixed electrodes further include a third electrode and a fourth electrode, The third direction from the fixing portion to the third electrode is along the first plane, The fourth direction from the fixing portion to the fourth electrode is along the first plane and intersects the third direction, The circuit portion further includes a first circuit, The first circuit is configured to supply an alternating current signal to at least one of the third electrode and the fourth electrode to vibrate the movable portion. The sensor according to claim 2.

4. The circuit portion further includes a second circuit, The sensor according to claim 3, wherein the second circuit is configured to control the first circuit so as to return the vibration state to the state when no external force is applied, based on the first value.

5. In a first vibration state where no external force is applied to the element unit, the movable unit vibrates along a first vibration direction. In a second vibration state where an external force is applied to the element unit, the vibration state includes a component in a second vibration direction intersecting the first vibration direction. The sensor according to claim 3, wherein the circuit unit adjusts the AC signal so as to return the second vibration state to the first vibration state, using the first value.

6. The sensor according to claim 5, wherein the circuit unit detects the angular velocity based on a change in the AC signal for the adjustment.

7. The sensor according to claim 1, wherein the movable unit includes a plurality of concentric annular portions centered on the fixed unit.

8. The sensor according to any one of claims 1 to 7, wherein the circuit unit is configured to vibrate the movable unit along the first direction when no external force is applied to the element unit.

9. The plurality of fixed electrodes further include a fifth electrode, a sixth electrode, a seventh electrode, and an eighth electrode. A fifth direction from the fixed unit to the fifth electrode is along the first plane. A sixth direction from the fixed unit to the sixth electrode is along the first plane and intersects the fifth direction. A seventh direction from the fixed unit to the seventh electrode is along the first plane. An eighth direction from the fixed unit to the eighth electrode is along the first plane and intersects the seventh direction. The sensor according to claim 3, wherein the circuit unit is configured to supply a first signal to at least any one of the fifth electrode, the sixth electrode, the seventh electrode, and the eighth electrode to adjust the vibration state.

10. The sensor according to claim 1, and a circuit control unit capable of controlling a circuit based on a signal obtained from the sensor. An electronic device comprising the same.

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