JP2015087334A - Output adjustment method of vibration element, vibration element, vibrator, electronic apparatus and mobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an output adjustment method of a vibration element capable of suppressing influences of noise caused by vibration leakage almost without changing a property such as a resonant frequency, the vibration element, a vibrator, an electronic apparatus and a mobile.SOLUTION: The output adjustment method of the vibration element including a base part, a vibration arm for driving, an electrode for driving, a first vibrating arm for detection, a second vibrating arm for detection, a first electrode for detection and a second electrode for detection includes: electrifying the electrode for driving; detecting a current outputted from the first electrode for detection and a current outputted from the second electrode for detection, respectively, while driving the vibrating arm for driving in a reciprocative manner; and changing an area of at least either the first electrode for detection or the second electrode for detection so as to reduce a difference between an absolute value of the current outputted from the first electrode for detection and an absolute value of the current outputted from the second electrode for detection.

Description

  The present invention relates to an output adjustment method for a vibration element, a vibration element, a vibrator, an electronic device, and a moving body.

Conventionally, angular velocity sensors that detect physical quantities such as angular velocity and acceleration are used for vehicle body control in vehicles, vehicle position detection of car navigation systems, vibration control correction (so-called camera shake correction) for digital cameras and video cameras, etc. (Vibration gyro sensor) is known.
In an angular velocity sensor provided with a vibration element called “H type” having a pair of drive vibrating arms and a pair of detection vibrating arms, the angular velocity is not applied to the angular velocity sensor due to, for example, variations during manufacturing. However, each vibration arm for detection vibrates in a state where the vibration arm for driving is vibrated by energization. This is called “vibration leakage”. In the vibration leakage, the vibrations of the detection vibrating arms are different from each other. For this reason, the current output from the detection electrode provided in one detection vibrating arm and the other detection vibrating arm are provided. Unlike the current output from the detection electrode, there is a problem that it is detected as noise. Such a problem also exists in other types of vibration elements.
Therefore, in Patent Document 1, it is configured such that vibration leakage occurs in the opposite direction between one and the other of the pair of vibration elements of the vibration element, and the output of one vibration element and the output of the other vibration element are An angular velocity sensor capable of canceling noise due to vibration leakage by taking the difference is disclosed.

However, the angular velocity sensor described in Patent Document 1 cannot sufficiently remove noise due to vibration leakage due to variations in manufacturing.
As another method, a vibration is leaked from a pair of vibration arms for detection by providing a weight on the vibration arm for detection of the vibration element, grinding a part of the weight and changing the mass of the weight. There is a way to match.
However, the above-described method has a problem that the resonance frequency of the vibration element changes unintentionally due to a change in the mass of the vibrating arm for detection.

JP-A-9-329444

  An object of the present invention is to provide an output adjustment method for a vibration element, a vibration element, a vibrator, an electronic device, and a moving body that can suppress the influence of noise due to vibration leakage without changing characteristics such as a resonance frequency. There is.

SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.
[Application Example 1]
The output adjustment method of the vibration element of the present invention includes a base,
A driving vibrating arm supported by the base;
A driving electrode provided on the driving vibrating arm;
A first detection vibrating arm and a second detection vibrating arm supported by the base at a position different from the driving vibration arm;
A first detection electrode provided on the first detection vibrating arm;
A vibration adjustment method for a vibration element having a second detection electrode provided on the second detection vibration arm,
The current output from the first detection electrode and the current output from the second detection electrode are respectively detected while the drive electrode is energized and the drive vibration arm is reciprocally driven. ,
The first detection electrode and the first detection electrode so that a difference between the absolute value of the current output from the first detection electrode and the absolute value of the current output from the second detection electrode is small; The area of at least one of the second detection electrode is changed.

Thereby, since the difference between the absolute value of the current output from the first detection electrode due to vibration leakage and the absolute value of the current output from the second detection electrode due to vibration leakage can be reduced, The influence of noise due to the vibration leakage can be suppressed, whereby the output of the vibration element is stabilized and accurate detection can be performed.
Further, since the output adjustment of the vibration element is performed by changing the area of at least one of the first detection electrode and the second detection electrode, characteristics such as the resonance frequency and sensitivity of the vibration element are almost changed. There is nothing.

[Application Example 2]
In the vibration element output adjustment method of the present invention, the voltage applied to the drive electrode when adjusting the output of the vibration element is set to be larger than the voltage applied to the drive electrode when using the vibration element. Is preferred.
Accordingly, when the output of the vibration element is adjusted, the driving vibration arm vibrates greatly, and the first detection vibration arm and the second detection vibration arm can be greatly vibrated, so that the first detection electrode In addition, the current output from the second detection electrode can be increased, whereby accurate adjustment can be performed.

[Application Example 3]
In the output adjustment method of the vibration element according to the aspect of the invention, the vibration element has a stress concentrated on the root part of the first detection vibrating arm more than the tip part, and the root part of the second detection vibration arm has the tip part. Stress is concentrated more than the part,
The first detection electrode has a difference between the absolute value of the current output from the first detection electrode and the absolute value of the current output from the second detection electrode. Changing at least one area of a portion located at a root portion of the first detection vibrating arm and a portion located at a root portion of the second detection vibrating arm of the second detection electrode. Coarse adjustment is performed to reduce the difference between the absolute value of the current output from the first detection electrode and the absolute value of the current output from the second detection electrode. At least one of a portion of the first detection electrode positioned at the tip of the first detection vibrating arm and a portion of the second detection electrode positioned at the tip of the second detection vibrating arm It is preferable to make fine adjustments by changing the area of.
Thereby, adjustment time can be shortened by rough adjustment, and it can adjust accurately by fine adjustment.

[Application Example 4]
In the output adjustment method of the vibration element according to the aspect of the invention, the absolute value of the current output from the first detection electrode in the state in which the drive electrode is energized and the drive vibration arm is reciprocated is A, When the absolute value of the current output from the second detection electrode is B and the absolute value of the current output from the drive electrode is C, A / C−B / C is 100 ppm or less. It is preferable to change the area of at least one of the first detection electrode and the second detection electrode.
As a result, the output of the vibration element becomes more stable and detection can be performed more accurately.

[Application Example 5]
In the output adjustment method of the vibration element according to the present invention, when the first axis, the second axis, and the third axis intersecting each other are assumed, the vibration element has the third axis as a normal line, and the driving vibration arm is The first detection vibrating arm and the second detection vibrating arm extend in the second axial direction, and are respectively in the second axial direction and opposite to the driving vibrating arm. Extending to
When the vibration element is used, when the vibration arm for driving reciprocates in the first axis direction and rotation about the second axis is applied to the vibration element, the vibration arm for driving is Preferably, the first detection vibrating arm and the second detection vibrating arm are reciprocally driven along the third axis direction, respectively. .
As a result, the output of the vibration element becomes more stable and detection can be performed more accurately.

[Application Example 6]
The vibration element of the present invention includes a base,
A driving vibrating arm supported by the base;
A driving electrode provided on the driving vibrating arm;
A first detection vibrating arm and a second detection vibrating arm supported by the base at a position different from the driving vibration arm;
A first detection electrode provided on the first detection vibrating arm;
A second detection electrode provided on the second detection vibrating arm and having a different area from the first detection electrode;
In the state where the drive electrode is energized and the drive vibration arm is driven to reciprocate, the absolute value of the current output from the first detection electrode is output from the second detection electrode. A / C-B / C is 100 ppm or less, where B is the absolute value of the current and C is the absolute value of the current output from the driving electrode.
Thereby, since A / C-B / C is 100 ppm or less, the influence of noise due to vibration leakage can be suppressed, the output of the vibration element is stabilized, and accurate detection can be performed.

[Application Example 7]
The vibrator of the present invention includes the vibration element of the present invention,
And a package containing the vibration element.
Thereby, the same effect as the vibration element of the present invention can be obtained.
[Application Example 8]
An electronic apparatus according to the present invention includes the vibration element according to the present invention.
Thereby, the same effect as the vibration element of the present invention can be obtained.
[Application Example 9]
The moving body of the present invention includes the vibration element of the present invention.
Thereby, the same effect as the vibration element of the present invention can be obtained.

It is a top view which shows typically the vibrator | oscillator using the vibration element adjusted with the adjustment method of the vibration element of this invention. FIG. 2 is a transverse sectional view of the vibrator shown in FIG. 1. 2A and 2B are diagrams illustrating a driving vibration arm of the vibrator illustrated in FIG. 1, in which FIG. 1A is an enlarged plan view and FIG. 2B is an enlarged cross-sectional view. It is a figure which shows the vibrating arm for a detection of the vibrator | oscillator shown in FIG. 1, (a) is an enlarged plan view, (b) is an enlarged cross-sectional view. FIG. 2 is a perspective view of a main part of a resonator element of the vibrator shown in FIG. 1. It is a figure for demonstrating the output adjustment of the vibration element of the vibrator | oscillator shown in FIG. 1 is a perspective view showing a configuration of a mobile (or notebook) personal computer using a vibration element of the present invention. It is a perspective view which shows the structure of the mobile telephone (PHS is also included) using the vibration element of this invention. It is a perspective view which shows the structure of the digital still camera using the vibration element of this invention. It is a perspective view which shows the structure of the motor vehicle to which the mobile body using the vibration element of this invention is applied.

Hereinafter, the output adjustment method, the vibration element, the vibrator, the electronic apparatus, and the moving body of the vibration element of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
<Embodiment>
FIG. 1 is a plan view schematically showing a vibrator using a vibration element adjusted by the method for adjusting a vibration element of the present invention. FIG. 2 is a cross-sectional view of the vibrator shown in FIG. FIGS. 3A and 3B are diagrams showing a driving vibrating arm of the vibrator shown in FIG. 1, wherein FIG. 3A is an enlarged plan view and FIG. 3B is an enlarged cross-sectional view. 4A and 4B are diagrams showing a detection vibrating arm of the vibrator shown in FIG. 1, wherein FIG. 4A is an enlarged plan view and FIG. 4B is an enlarged cross-sectional view. FIG. 5 is a perspective view of a main part of the resonator element of the vibrator shown in FIG. FIG. 6 is a diagram for explaining output adjustment of the vibration element of the vibrator shown in FIG.

  In the following, for convenience of explanation, an x-axis (first axis), a y-axis (first axis), and a z-axis (first axis) are assumed as three axes that are orthogonal (intersect) with each other, and FIG. In FIG. 5, each axis is illustrated, a direction parallel to the x-axis is “x-axis direction”, a direction parallel to the y-axis is “y-axis direction”, and a direction parallel to the z-axis is “z-axis direction” " Moreover, the positive / negative of each direction is as showing with the arrow in a figure.

A vibrator (sensor device) 1 shown in FIGS. 1 and 2 is a gyro sensor that detects an angular velocity.
Such a vibrator 1 can be used, for example, for camera shake correction of an imaging device, posture detection of a vehicle or the like in a mobile navigation system using a GPS (Global Positioning System) satellite signal, posture control, and the like.
The vibrator 1 includes a vibration element 2 and a package 4 that houses the vibration element 2.

Hereinafter, each part which comprises the vibrator | oscillator 1 is demonstrated sequentially.
The vibration element 2 is a gyro sensor element that detects an angular velocity around one axis.
As shown in FIG. 1, the vibration element 2 has the z-axis as a normal line, and includes the vibration substrate 20, drive electrode groups 51 and 52, and detection electrode groups 53 and 54.
The vibration substrate 20 includes a base portion 21, a pair of drive vibration arms 221 and 222, a pair of detection vibration arms 231 and 232, a support portion 25, and four connection portions 261, 262, 263, and 264. This is a so-called “H-type” vibration substrate. In the present embodiment, the base 21, the driving vibrating arms 221, 222, the detecting vibrating arms 231, 232, the support portion 25, and the connecting portions 261 to 264 are integrally formed of a piezoelectric material. The detection vibration arm 231 is a first detection vibration arm, and the detection vibration arm 232 is a second detection vibration arm.

  The piezoelectric material is not particularly limited, but it is preferable to use quartz. Thereby, the characteristic of the vibration element 2 can be made excellent. Quartz crystal has three crystal axes, an X axis (electrical axis), a Y axis (mechanical axis), and a Z axis (optical axis) that are orthogonal to each other. For example, the base 21, the driving vibrating arms 221 and 222, the detecting vibrating arms 231 and 232, the support portion 25, and the connecting portions 261 to 264 have a Z axis in the thickness direction and are parallel to the X axis and the Y axis. It can be formed by etching a substrate made of quartz having a plate surface. The thickness of the substrate is appropriately set according to the oscillation frequency (resonance frequency), outer size, workability, and the like of the vibration element 2. In the present embodiment, the case where the base 21, the driving vibrating arms 221, 222, the outgoing vibrating arms 231, 232, the support portion 25, and the connecting portions 261 to 264 are integrally formed of quartz will be described as an example. To do. In the present embodiment, the X axis of the crystal axis is coincident with the x axis of the absolute coordinate axis, the Y axis of the crystal axis is coincident with the y axis of the absolute coordinate axis, and the Z axis of the crystal axis is the absolute coordinate axis. It coincides with the z axis.

The base portion 21 is supported by four support portions 261 to 264 on a support portion 25 formed so as to surround the base portion 21 in plan view. Each of the four connecting portions 261 to 264 has an elongated shape, one end is connected to the base portion 21, and the other end is connected to the support portion 25. Each of the connecting portions 261 to 264 is bent a plurality of times in the middle of the longitudinal direction.
The base 21 has a rectangular shape having a pair of sides extending in the y-axis direction and a pair of sides extending in the x-axis direction when viewed from the z-axis direction. In other words, the base portion 21 has a pair of sides parallel to the extending direction of the driving vibrating arms 221 and 222 and the extending direction of the driving vibrating arms 221 and 222 as described later when viewed in plan. And a rectangular shape having a pair of vertical sides. Thereby, as described later, the detection vibrating arms 231 and 232 are vibrated efficiently in the second direction (the directions of arrows E1 and E2 shown in FIG. 5) in accordance with the driving vibration of the driving vibrating arms 221 and 222 ( In-plane vibration) (see FIG. 5).

  Further, as shown in FIG. 1, the base 21 in the present embodiment has a quadrangular shape, and the length in the x-axis direction is preferably longer than the length in the y-axis direction. That is, the length of the base 21 in the direction perpendicular to the extending direction of the driving vibrating arms 221 and 222 in plan view is L1, and the extending direction of the driving vibrating arms 221 and 222 in plan view is When the length of the base 21 in the parallel direction is L2, it is preferable to satisfy the relationship L1> L2. By satisfying such a relationship between L1 and L2, the detection vibrating arms 231 and 232 can be efficiently vibrated in the second directions E1 and E2 along with the driving vibration of the driving vibrating arms 221 and 222. .

The drive vibrating arms 221 and 222 each extend (extend) from the base portion 21 in the y-axis direction (+ y direction). Thus, the driving vibrating arms 221 and 222 are provided so as to be parallel to each other. The drive vibrating arms 221 and 222 are arranged to be separated from each other in the x-axis direction. Thereby, the driving vibrating arms 221 and 222 can vibrate independently. As shown in FIG. 3B, the cross-sections of the driving vibrating arms 221 and 222 each have a rectangular shape composed of a pair of sides parallel to the x axis and a pair of sides parallel to the z axis. There is no.
Further, hammer heads (weight portions) 2211 and 2221 are formed at the distal ends of the driving vibrating arms 221 and 222, respectively. Thereby, the length of the driving vibrating arms 221 and 222 can be shortened, and the size of the vibrating element 2 can be reduced. The hammer heads 2211 and 2221 may be omitted.

  The driving vibrating arm 221 is provided with a driving electrode group 51, and similarly, the driving vibrating arm 222 is provided with a driving electrode group 52. Hereinafter, the drive electrode group 51 will be described representatively. The drive electrode group 52 is composed of four drive electrodes 521, 522, 523, and 524, and is the same as the drive electrode group 51 described later, and thus the description thereof is omitted. The drive vibrating arm 222, the drive electrode group 52, and the drive electrodes 521, 522, 523, and 524 are shown in parentheses in FIG.

As shown in FIGS. 3A and 3B, the drive electrode group 51 includes a drive electrode 511 provided on the upper surface of the drive vibrating arm 221 and a drive provided on the lower surface of the drive vibrating arm 221. The driving electrode 512, the driving electrode 513 provided on the left side surface of the driving vibrating arm 221, and the driving electrode 514 provided on the right side surface of the driving vibrating arm 221 are configured.
The drive electrode 511 and the drive electrode 512 are electrically connected to each other via a wiring (not shown) so as to have the same potential. Further, the drive electrode 513 and the drive electrode 514 are electrically connected to each other via a wiring (not shown) so as to have the same potential. Such driving electrodes 511 and 512 are electrically connected to terminals 57a provided on the support portion 25 shown in FIG. Further, the drive electrodes 513 and 514 are electrically connected to a terminal 57b provided on the support portion 25 shown in FIG. The drive electrodes 521 and 522 of the drive electrode group 52 are electrically connected to the drive electrodes 513 and 514, and the drive electrodes 523 and 524 of the drive electrode group 52 are connected to the drive electrodes. The electrodes 511 and 512 are electrically connected.

  The detection vibrating arms 231 and 232 extend (extend) from the base portion 21 in the y-axis direction and on the opposite side (−y direction) from the driving vibrating arms 221 and 222, respectively. Accordingly, the detection vibrating arms 231 and 232 are provided in parallel to each other. The detection vibrating arms 231 and 232 extend in the opposite direction to the driving vibrating arms 221 and 222 described above. The detection vibrating arms 231 and 232 are arranged apart from each other in the x-axis direction. Accordingly, the detection vibrating arms 231 and 232 can vibrate independently. As shown in FIG. 4B, the cross-sections of the vibrating arms for detection 231 and 232 each have a rectangular shape composed of a pair of sides parallel to the x axis and a pair of sides parallel to the z axis. There is no.

Further, hammer heads (weight portions) 2311 and 2321 are formed at the distal ends of the detection vibrating arms 231 and 232, respectively. Thereby, the length of the vibrating arms 231 and 232 for detection can be shortened, and the size of the vibrating element 2 can be reduced. The hammer heads 2311 and 2321 may be omitted.
Such detection vibrating arms 231 and 232 have a first direction (arrows C1 and D1, C2 and D2 shown in FIG. 5) in accordance with physical quantities applied to the driving vibrating arms 221 and 222, as will be described later. ) And a second direction (arrows E1 and E2 shown in FIG. 5) different from the first direction in accordance with the drive vibration of the drive vibration arms 221 and 222.

  1, the detection vibrating arm 231 is provided with a detection electrode group (first detection electrode group) 53. Similarly, the detection vibrating arm 232 includes a detection electrode group. (Second detection electrode group) 54 is provided. In this way, by providing the detection electrode groups 53 and 54 on the detection vibration arms 231 and 232 provided separately from the drive vibration arms 221 and 222, the detection electrode groups 53 and 54 have the detection electrode groups. The electrode area (area of the portion functioning as an electrode) can be increased. Therefore, the detection sensitivity of the vibration element 2 can be improved.

  Hereinafter, the detection electrode group 53 will be described representatively. The detection electrode group 54 is composed of four detection electrodes (second detection electrodes) 541, 542, 543, and 544, which are the same as the detection electrode group 53 described later. Description is omitted. The detection vibrating arm 232, the detection electrode group 54, and the detection electrodes 541, 542, 543, and 544 are shown in parentheses in FIG.

  As shown in FIGS. 4A and 4B, the detection electrode group 53 includes detection electrodes (first detection electrodes) 531 and 532 provided on the upper surface of the detection vibrating arm 231, and detection electrodes. It comprises detection electrodes (first detection electrodes) 533 and 534 provided on the lower surface of the vibrating arm 231. Here, the detection electrodes 531 and 533 are respectively provided on one side in the width direction of the detection vibrating arm 231 (left side in FIG. 4), and the detection electrodes 532 and 534 are respectively used for detection. The vibration arm 231 is provided on the other side (the right side in FIG. 4) in the width direction.

  The detection electrode 531 and the detection electrode 534 are electrically connected to each other via a wiring (not shown) so as to have the same potential. Further, the detection electrode 532 and the detection electrode 533 are electrically connected to each other via a wiring (not shown) so as to have the same potential. Such detection electrodes 531 and 534 are electrically connected to terminals 57c provided on the support portion 25 shown in FIG. Further, the detection electrodes 532 and 533 are electrically connected to a terminal 57e provided on the support portion 25 shown in FIG. The detection electrode group 54 is electrically connected to terminals 57d and 57f provided on the support portion 25 shown in FIG. 1 via a wiring (not shown).

  Note that a part of each of the detection electrodes 531 to 534 may be provided on the base 21, and similarly, a part of each of the detection electrodes 541 to 544 may be provided on the base 21. . And in the output adjustment of the vibration element 2 to be described later, the area of the portion provided in the base 21 of the detection electrodes 531 to 534 may be changed. Similarly, of the detection electrodes 541 to 544 You may change the area of the site | part provided in the base 21.

  In the vibration element 2 configured as described above, in use, a driving signal (driving voltage) is applied between the terminal 57a and the terminal 57b, that is, the driving electrodes 511 to 514 and 521 to 524 are applied. When energized, as shown in FIG. 5, the vibration arm for driving 221 and the vibration arm for driving 222 are bent and vibrated (drive vibration) (reciprocating in the x-axis direction) so as to approach and separate from each other. That is, the driving vibrating arm 221 is bent in the direction of arrow A1 in FIG. 5 and the driving vibrating arm 222 is bent in the direction of arrow A2 in FIG. 5, and the driving vibrating arm 221 is in FIG. The state in which the drive vibrating arm 222 is bent in the direction of the arrow B1 and the state in which the drive vibrating arm 222 is bent in the direction of the arrow B2 in FIG.

If the angular velocity ω about the y-axis is applied to the vibrating element 2 with the driving vibrating arms 221 and 222 being driven in this way, the driving vibrating arms 221 and 222 are mutually moved in the z-axis direction by Coriolis force. Bends and vibrates in the opposite direction (reciprocating drive in the z-axis direction). Accordingly, the detection vibrating arms 231 and 232 perform bending vibration (detection vibration) (reciprocating drive in the z-axis direction) on the opposite sides in the z-axis direction (first direction). That is, the detection vibrating arm 231 is bent in the direction of arrow C1 in FIG. 5 and the detection vibrating arm 232 is bent in the direction of arrow C2 in FIG. 5, and the detection vibrating arm 231 is in FIG. The state in which the detection vibrating arm 232 is bent in the direction of the arrow D2 in FIG.
The angular velocity ω applied to the vibration element 2 can be obtained by detecting the charges generated in the detection electrode groups 53 and 54 by the detection vibration of the detection vibration arms 231 and 232.

  Further, at this time, the detection vibrating arms 231 and 232 are flexibly vibrated in a direction (second direction different from the first direction) that approaches and separates from each other with the driving vibration of the driving vibrating arms 221 and 222. reciprocating in the x-axis direction). That is, the detection vibrating arms 231 and 232 bend and vibrate in the direction indicated by the arrow E1 in FIG. 5 regardless of whether or not a physical quantity is added to the driving vibration arms 221 and 222. At the same time, the detection vibrating arm 232 is flexibly vibrated in the direction indicated by the arrow E2 in FIG.

  The charges generated in the detection electrode groups 53 and 54 are detected as current. Further, for example, the currents are the current between the detection electrodes 531 and 534 and the detection electrodes 532 and 533 of the detection electrode group 53, and the detection electrodes 541 and 544 and the detection electrodes of the detection electrode group 54. The current between 542 and 543 is added and detected. In the detection of the current, it can be said that the difference between the currents is taken because the electrode arrangement of the detection electrode group 53 and the detection electrode group 54 is opposite. As a result, an output current that is approximately twice as large as that in the case of one detection vibrating arm can be obtained.

Here, when manufacturing the vibration element 2, the vibration element 2 has the following configuration and characteristics by performing output adjustment described later on the vibration element 2.
First, at least one of the detection electrodes 531 to 534 and at least one of the detection electrodes 531 to 534 have different areas.
Further, when the predetermined electrodes of the drive electrodes 511 to 514 and 521 to 524 are energized, the drive vibration arms 221 and 222 vibrate in the x-axis direction, and no physical quantity is applied to the vibration element 2, the detection The absolute value of the current output from the electrodes 531 to 534 is A, the absolute value of the current output from the detection electrodes 541 to 544 is B, and the drive electrodes 511 to 514 and 521 to 524 are output from predetermined electrodes. When the absolute value of the current to be detected is C, the leakage signal generated from the detection electrodes 531 to 534 is A / C, and the leakage signal generated from the detection electrodes 541 to 544 is B / C, the difference, that is, A / C-B / C is 100 ppm or less. Thereby, the influence of noise due to vibration leakage can be suppressed, the output of the vibration element 2 is stabilized, and accurate detection can be performed.

As shown in FIG. 2, the package 4 includes a base member (base) 41 having a recess opening upward, and a lid member (lid) 42 provided so as to cover the recess of the base member 41. The base member 41 and the lid member 42 form an internal space in which the vibration element 2 is accommodated.
The base member 41 includes a flat plate body (plate portion) 411 and a frame body (frame portion) 412 joined to the outer peripheral portion of the upper surface of the plate body 411.
Such a base member 41 is made of, for example, an aluminum oxide sintered body, crystal, glass, or the like.

As shown in FIG. 2, the upper surface of the plate body 411 of the base member 41 (the surface on the side covered with the lid member 42) is a joining member such as an adhesive that includes, for example, an epoxy resin, an acrylic resin, or the like. By 81, the support part 25 of the vibration element 2 mentioned above is joined. Thereby, the vibration element 2 is supported and fixed to the base member 41.
Further, as shown in FIGS. 1 and 2, a plurality of internal terminals 71 are provided on the upper surface of the base member 41.
The plurality of internal terminals 71 are electrically connected to the above-described terminals 57a to 57f of the vibration element 2 through, for example, wiring configured by bonding wires.

On the other hand, a plurality of external terminals 73 that are used when mounted on a device (external device) in which the vibrator 1 is incorporated are provided on the lower surface of the plate body 411 of the base member 41 (the bottom surface of the package 4).
The plurality of external terminals 73 are electrically connected to the plate body 411 via internal wiring (not shown). Thereby, the plate body 411 and the plurality of external terminals 73 are electrically connected.
Each of the internal terminals 71 and the external terminals 73 is made of a metal film in which a film of nickel (Ni), gold (Au) or the like is laminated on a metallized layer of tungsten (W) or the like by plating or the like.

A lid member 42 is airtightly joined to such a base member 41. Thereby, the inside of the package 4 is hermetically sealed.
The lid member 42 is made of, for example, the same material as the base member 41 or a metal such as Kovar, 42 alloy, stainless steel, or the like.
The joining method of the base member 41 and the lid member 42 is not particularly limited. For example, a joining method using an adhesive composed of a brazing material, a curable resin, or the like, a welding method such as seam welding, laser welding, or the like is used. be able to. Further, such bonding is performed under reduced pressure or under an inert gas atmosphere, whereby the inside of the package 4 can be maintained in a reduced pressure state or an inert gas filled state.

Next, an output adjustment method (manufacturing method) of the vibration element 2 will be described.
In the vibration element 2, the detection vibration arms 231 and 232 vibrate in a state where the drive vibration arms 221 and 224 are vibrated by energization even if no physical quantity is added to the vibration element 2 due to variations at the time of manufacture. Then, charges are generated in the detection electrodes 531 to 534 and the detection electrodes 541 to 544, respectively.

  Therefore, in the output adjustment of the vibration element 2, power is supplied to predetermined electrodes of the drive electrodes 511 to 514 and 521 to 524 to vibrate the drive vibration arms 221 and 222 (reciprocating drive). When not added, the detection electrode 531 is reduced so that the difference between the absolute value of the current output from the detection electrodes 531 to 534 and the absolute value of the current output from the detection electrodes 541 to 544 is reduced. The area of either one or both of at least one of -534 and at least one of the detection electrodes 541-544 is changed. This change in area may be an increase in area or a decrease in area. Further, the area where the areas of the detection electrodes 531 to 534 are changed may be either a part provided on the drive vibrating arm 221 or a part provided on the base 21. Similarly, the areas of the detection electrodes 541 to 544 may be changed. The part to be changed may be either a part provided on the driving vibrating arm 222 or a part provided on the base 21. Hereinafter, the output adjustment of the vibration element 2 will be described in detail.

  First, as shown in FIG. 6, the vibration element 2 is electrically connected to the detection electrodes 531 to 534 with a current detection unit 91 that detects currents output from the detection electrodes 531 to 534. A current detection unit 92 that detects current output from the electrodes 541 to 544 is electrically connected to the detection electrodes 541 to 544. In FIG. 6, the current detection unit 91 is illustrated as being connected only to the detection electrodes 531 and 532, but the detection electrodes 531 and 534 are electrically connected to each other via wiring (not illustrated). Since the detection electrodes 532 and 533 are electrically connected to each other via a wiring (not shown), the current detection unit 91 is also electrically connected to the detection electrodes 533 and 534. Similarly, in FIG. 6, the current detection unit 92 is illustrated as being connected only to the detection electrodes 541 and 542, but the detection electrodes 541 and 544 are electrically connected to each other via wiring (not illustrated). Since the detection electrodes 542 and 543 are electrically connected to each other via a wiring (not shown), the current detection unit 92 is also electrically connected to the detection electrodes 543 and 544. As the current detection units 91 and 92, for example, an ammeter is used.

  Next, power is supplied to predetermined electrodes of the drive electrodes 511 to 514 and 521 to 524 to vibrate (reciprocate) the drive vibrating arms 221 and 222. The current output from the detection electrodes 531 to 534 is detected by the current detection unit 91 in a state where no physical quantity is applied to the vibration element 2. Similarly, the detection electrodes 541 to 541 are detected by the current detection unit 92. The current output from 544 is detected.

The applied voltage to the drive electrodes 511 to 514 and 521 to 524 when adjusting the output of the vibration element 2 is set larger than the applied voltage to the drive electrodes 511 to 514 and 521 to 524 when the vibration element 2 is used. It is preferable to do. As a result, when adjusting the output of the vibration element 2, the driving vibrating arms 221 and 222 can vibrate greatly, and the detecting vibrating arms 231 and 232 can be vibrated greatly, and therefore output from the detection electrodes 531 to 534. It is possible to increase the current and the current output from the detection electrodes 541 to 544, and thereby to perform accurate adjustment.
Note that the voltages applied to the drive electrodes 511 to 514 and 521 to 524 when adjusting the output of the vibration element 2 are the same as the voltages applied to the drive electrodes 511 to 514 and 521 to 524 when the vibration element 2 is used. It is preferably 5 times or more and 3 times or less, and more preferably 2 times or more and 3 times or less.

  Next, the current output from the detection electrodes 531 to 534 and the current output from the detection electrodes 541 to 544 are compared, and the absolute value of the current output from the detection electrodes 531 to 534 is compared with the detection current. The area of one or both of at least one of the detection electrodes 531 to 534 and at least one of the detection electrodes 541 to 544 so that the difference from the absolute value of the current output from the electrodes 541 to 544 is reduced. To change. In addition, when changing the area of the detection electrodes 531 to 534, the number of detection electrodes for changing the area may be one, two, three, or all of them. Specifically, the case where the area of the detection electrode 531 is changed will be described. Similarly, when the areas of the detection electrodes 541 to 544 are changed, the number of detection electrodes for changing the area may be one, two, three, or all of them. Typically, a case where the area of the detection electrode 541 is changed will be described.

  When the absolute value of the current output from the detection electrodes 531 to 534 is larger than the absolute value of the current output from the detection electrodes 541 to 544, the area of the detection electrode 531 is reduced or detected. The area of the electrode for detection 541 is increased, or the area of the electrode for detection 531 is decreased, and the area of the electrode for detection 541 is increased. However, among these, it is preferable to reduce the area of the detection electrode 531 from the viewpoint that the processing can be performed easily and quickly.

When the absolute value of the current output from the detection electrodes 541 to 544 is larger than the absolute value of the current output from the detection electrodes 531 to 534, the area of the detection electrode 541 is decreased, or The area of the detection electrode 531 is increased, or the area of the detection electrode 541 is decreased and the area of the detection electrode 531 is increased. However, among these, it is preferable to reduce the area of the detection electrode 541 for the same reason as described above.
The method for reducing the area of the detection electrodes 531 and 541 is not particularly limited, and examples thereof include laser trimming and grinding. The method for increasing the area of the detection electrodes 531 and 541 is not particularly limited, and examples thereof include vapor deposition such as sputtering using FIB (focused ion beam).

  The current detection for detecting the current output from the detection electrodes 531 to 534 and the current output from the detection electrodes 541 to 544 and the area changing process for changing the areas of the detection electrodes 531 and 541 are detected. The measurement is repeated until the difference between the absolute value of the current output from the electrodes 531 to 534 and the absolute value of the current output from the detection electrodes 541 to 544 is equal to or less than the target value. In this case, the difference (A / C−B / C) between the leakage signal A / C generated from the detection electrodes 531 to 534 and the leakage signal B / C generated from the detection electrodes 541 to 544 is set to 100 ppm or less. Is preferred. Thereby, the influence of noise due to vibration leakage can be suppressed, the output of the vibration element 2 is stabilized, and accurate detection can be performed.

Further, in the vibration element 2, stress is concentrated at the base portions of the detection vibrating arms 231 and 232 than at the tip portion, and the stress applied to the root portions is increased.
Thus, when the detection vibrating arms 231 and 232 vibrate, the detection vibrating arms 531 of the detection electrodes 531 to 534 are located at the bases of the detection vibrating arms 231 of the detection electrodes 531 to 534. A larger charge is generated than the part located at the tip.
For this reason, if the area of the part located in the base part of the detection vibration arm 231 of the detection electrodes 531 to 534 is changed, the area of the part located in the tip part of the detection vibration arm 231 of the detection electrodes 531 to 534 is changed. The output current changes much more than when changing. The same applies to the detection electrodes 541 to 544.

  Therefore, in the output adjustment of the vibration element 2, first, a portion located at the root portion of the detection vibrating arm 231 of the detection electrode 531 and a portion located at the root portion of the detection vibrating arm 232 of the detection electrode 541 are detected. Coarse adjustment is performed by changing at least one of the areas. Thereafter, the area of at least one of the part located at the distal end portion of the detection vibrating arm 231 of the detection electrode 531 and the part located at the distal end portion of the detection vibrating arm 232 of the detection electrode 541 is changed. Make fine adjustments. Thereby, adjustment time can be shortened by rough adjustment, and it can adjust accurately by fine adjustment.

  In the output adjustment of the vibration element 2, an external power supply is electrically connected to the drive electrodes 511 to 514 and 521 to 524 without using the drive circuit of the vibrator 1, and the drive electrodes 511 to 111 are driven by the external power supply. 514 and 521 to 524 may be energized. Thereby, a voltage of an arbitrary magnitude can be applied to the drive electrodes 511 to 514 and 521 to 524 without being restricted by the drive circuit of the vibrator 1.

As described above, according to the output adjustment method of the vibration element 2, the drive electrodes 511 to 514 and 521 to 524 are energized to vibrate (reciprocate) the drive vibration arms 221 and 222. In the state where no physical quantity is added, the difference between the absolute value of the current output from the detection electrodes 541 to 544 and the absolute value of the current output from the detection electrodes 541 to 544 can be reduced. The influence of noise due to vibration leakage can be suppressed, whereby the output of the vibration element 2 is stabilized and accurate detection can be performed.
Further, since the output adjustment of the vibration element 2 is performed by changing the area of any of the detection electrodes 531 to 434 and 541 to 544, characteristics such as the resonance frequency and sensitivity of the vibration element 2 are hardly changed. .

<Embodiment of Electronic Device>
Next, an electronic device to which the vibration element 2 is applied will be described in detail with reference to FIGS.
FIG. 7 is a perspective view illustrating a configuration of a mobile (or notebook) personal computer to which an electronic device including the resonator element according to the invention is applied.

  In this figure, a personal computer 1100 includes a main body portion 1104 provided with a keyboard 1102 and a display unit 1106 provided with a display portion 1108. The display unit 1106 is rotated with respect to the main body portion 1104 via a hinge structure portion. It is supported movably. Such a personal computer 1100 has a built-in vibrator 1 (vibrating element 2) that functions as an angular velocity detecting means (gyro sensor).

FIG. 8 is a perspective view illustrating a configuration of a mobile phone (including PHS) to which an electronic device including the vibration element of the invention is applied.
In this figure, a cellular phone 1200 includes a plurality of operation buttons 1202, an earpiece 1204, and a mouthpiece 1206, and a display unit 1208 is disposed between the operation buttons 1202 and the earpiece 1204. Such a cellular phone 1200 incorporates a vibrator 1 (vibrating element 2) that functions as an angular velocity detecting means (gyro sensor).

  FIG. 9 is a perspective view illustrating a configuration of a digital still camera to which an electronic device including the resonator element according to the invention is applied. In this figure, connection with an external device is also simply shown. Here, an ordinary camera sensitizes a silver halide photographic film with a light image of a subject, whereas a digital still camera 1300 photoelectrically converts a light image of a subject with an imaging device such as a CCD (Charge Coupled Device). An imaging signal (image signal) is generated.

A display unit is provided on the back of a case (body) 1302 in the digital still camera 1300, and is configured to perform display based on an imaging signal from the CCD. The display unit 1310 displays a subject as an electronic image. Function as.
A light receiving unit 1304 including an optical lens (imaging optical system), a CCD, and the like is provided on the front side (the back side in the drawing) of the case 1302.
When the photographer confirms the subject image displayed on the display unit and presses the shutter button 1306, the CCD image pickup signal at that time is transferred and stored in the memory 1308.

In the digital still camera 1300, a video signal output terminal 1312 and an input / output terminal 1314 for data communication are provided on the side surface of the case 1302. As shown in the figure, a television monitor 1430 is connected to the video signal output terminal 1312 and a personal computer 1440 is connected to the input / output terminal 1314 for data communication as necessary. Further, the imaging signal stored in the memory 1308 is output to the television monitor 1430 or the personal computer 1440 by a predetermined operation.
Such a digital still camera 1300 has a built-in vibrator 1 (vibrating element 2) that functions as an angular velocity detecting means (gyro sensor).

  In addition to the personal computer (mobile personal computer) in FIG. 7, the mobile phone in FIG. 8, and the digital still camera in FIG. 9, the electronic device including the vibration element is, for example, an ink jet type ejection device (for example, an ink jet printer). , Laptop personal computers, TVs, video cameras, video tape recorders, car navigation devices, pagers, electronic notebooks (including those with communication functions), electronic dictionaries, calculators, electronic game devices, word processors, workstations, videophones, crime prevention TV monitors, electronic binoculars, POS terminals, medical devices (eg, electronic thermometers, blood pressure monitors, blood glucose meters, electrocardiogram measuring devices, ultrasonic diagnostic devices, electronic endoscopes), fish detectors, various measuring devices, instruments (eg, , Vehicle, aircraft, ship instrumentation , It can be applied to a flight simulator or the like.

<Embodiment of moving body>
Next, a moving body to which the vibration element is applied will be described in detail with reference to FIG.
FIG. 10 is a perspective view illustrating a configuration of an automobile to which a moving body including the vibration element of the present invention is applied.
The automobile 1500 includes a built-in vibrator 1 (vibration element 2) that functions as an angular velocity detection unit (gyro sensor), and the vibration element 2 can detect the posture of the vehicle body 1501. The detection signal of the vibration element 2 is supplied to the vehicle body posture control device 1502, and the vehicle body posture control device 1502 detects the posture of the vehicle body 1501 based on the signal, and controls the stiffness of the suspension according to the detection result. The brakes of the individual wheels 1503 can be controlled. In addition, such posture control can be used by a biped robot or a radio control helicopter. As described above, the vibrator 1 (vibration element 2) is incorporated in realizing the posture control of various moving bodies.

As described above, the output adjustment method, the vibration element, the vibrator, the electronic device, and the moving body of the vibration element of the present invention have been described based on the illustrated embodiment, but the present invention is not limited to this, The configuration can be replaced with any configuration having a similar function. Moreover, other arbitrary structures and processes may be added to the present invention.
In the above-described embodiment, the number of vibrating arms is four. However, the number of vibrating arms is not limited to this, and may be one, two, three, or five or more, for example.
In the above-described embodiment, a so-called “H-type” vibration element has been described as an example. However, the present invention is not limited to this. For example, “double T-type”, “bipod tuning fork”, “tripod tuning fork”, “comb tuning fork” The present invention can be applied to various vibration elements (gyro elements) such as “tooth type”, “orthogonal type”, and “prism type”.

  DESCRIPTION OF SYMBOLS 1 ... Vibrator (sensor device) 2 ... Vibrating element 20 ... Vibrating substrate 21 ... Base 221 ... Driving vibration arm 2211 ... Hammer head 222 ... Driving vibration arm 2221 ... Hammer head 231 ... Vibrating arm for detection 2311 …… Hammer head 232 …… Vibrating arm for detection 2321 …… Hammer head 25 …… Supporting portion 261 …… Connecting portion 262 …… Connecting portion 263 …… Connecting portion 264 …… Connecting portion 4 …… Package 41 ... Base member (base) 411 ... Plate body (plate portion) 412 ... Frame body (frame portion) 42 ... Lid member 51 ... Drive electrode group 511 ... Drive electrode 512 ... Driving electrode 513 ...... Driving electrode 514 ...... Driving electrode 52 ...... Driving electrode group 53 ...... Detection electrode group 531 ...... Detection electrode 532 ...... Output electrode 533 …… Detection electrode 534 …… Detection electrode 54 …… Detection electrode group 57a …… Terminal 57b …… Terminal 57c …… Terminal 57d …… Terminal 57e …… Terminal 57f …… Terminal 71 …… Internal Terminal 73 ... External terminal 81 ... Joining member 91, 92 ... Current detection part 1100 ... Personal computer 1102 ... Keyboard 1104 ... Body part 1106 ... Display unit 1108 ... Display part 1200 ... Mobile phone 1202 ... ... Operation buttons 1204 ... Entrance 1206 ... Speaker 1208 ... Display 1300 ... Digital still camera 1302 ... Case 1304 ... Light receiving unit 1306 ... Shutter button 1308 ... Memory 1310 ... Display 1312 ... ... Video signal output terminal 1314 ... Input / output terminal 1430 ... TV monitor 1440 ... Personal computer 1500 ... Automobile 1501 ... Car body 1502 ... Car body attitude control device 1503 ... Wheel A1 ... Arrow A2 ... Arrow B1 ... Arrow B2 ... Arrow C1 ... ... Arrow C2 ... Arrow D1 ... Arrow D2 ... Arrow E1 ... Arrow E2 ... Arrow L1 ... Length L2 ... Length ω ... Angular velocity

Claims (9)

The base,
A driving vibrating arm supported by the base;
A driving electrode provided on the driving vibrating arm;
A first detection vibrating arm and a second detection vibrating arm supported by the base at a position different from the driving vibration arm;
A first detection electrode provided on the first detection vibrating arm;
A method for adjusting the output of a vibration element having a second detection electrode provided on the second detection vibration arm,
The current output from the first detection electrode and the current output from the second detection electrode are respectively detected while the drive electrode is energized and the drive vibration arm is reciprocally driven. ,
The first detection electrode and the first detection electrode so that a difference between the absolute value of the current output from the first detection electrode and the absolute value of the current output from the second detection electrode is small; A method for adjusting an output of a vibration element, wherein an area of at least one of the second detection electrode and the second detection electrode is changed.   2. The output adjustment method for a vibrating element according to claim 1, wherein an applied voltage to the driving electrode when adjusting the output of the vibrating element is set to be larger than an applied voltage to the driving electrode when using the vibrating element. . In the vibration element, the stress is concentrated at the root part of the first detection vibrating arm than the tip part, and the stress is concentrated at the root part of the second detection vibrating arm than the tip part,
The first detection electrode has a difference between the absolute value of the current output from the first detection electrode and the absolute value of the current output from the second detection electrode. Changing at least one area of a portion located at a root portion of the first detection vibrating arm and a portion located at a root portion of the second detection vibrating arm of the second detection electrode. Coarse adjustment is performed to reduce the difference between the absolute value of the current output from the first detection electrode and the absolute value of the current output from the second detection electrode. At least one of a portion of the first detection electrode positioned at the tip of the first detection vibrating arm and a portion of the second detection electrode positioned at the tip of the second detection vibrating arm The vibration element according to claim 1, wherein fine adjustment is performed by changing an area of the vibration element. Output adjustment method.   In the state where the drive electrode is energized and the drive vibration arm is driven to reciprocate, the absolute value of the current output from the first detection electrode is output from the second detection electrode. When the absolute value of the current is B and the absolute value of the current output from the drive electrode is C, the first detection electrode and the first electrode are set so that A / C−B / C is 100 ppm or less. The method for adjusting the output of a vibrating element according to claim 1, wherein the area of at least one of the two detection electrodes is changed. Assuming a first axis, a second axis, and a third axis that intersect each other, the vibration element has the third axis as a normal line, and the driving vibrating arm extends in the second axis direction, Each of the first detection vibrating arm and the second detection vibrating arm extends in a direction opposite to the drive vibrating arm in the second axial direction,
When the vibration element is used, when the vibration arm for driving reciprocates in the first axis direction and rotation about the second axis is applied to the vibration element, the vibration arm for driving is The reciprocating drive in the third axis direction, and the first detection vibrating arm and the second detection vibrating arm are reciprocatingly driven in the third axis direction, respectively. The method for adjusting the output of the vibration element according to claim 1. The base,
A driving vibrating arm supported by the base;
A driving electrode provided on the driving vibrating arm;
A first detection vibrating arm and a second detection vibrating arm supported by the base at a position different from the driving vibration arm;
A first detection electrode provided on the first detection vibrating arm;
A second detection electrode provided on the second detection vibrating arm and having a different area from the first detection electrode;
In the state where the drive electrode is energized and the drive vibration arm is driven to reciprocate, the absolute value of the current output from the first detection electrode is output from the second detection electrode. A vibration element, wherein A / C-B / C is 100 ppm or less, where B is an absolute value of current and C is an absolute value of current output from the driving electrode. The vibration element according to claim 6;
And a package containing the vibration element.   An electronic apparatus comprising the vibration element according to claim 6.   A moving body comprising the vibration element according to claim 6.

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