JP2015152549A - Control method of physical quantity sensor, physical quantity sensor using the control method and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic apparatus capable of reducing noises ensuring use feeling of a user of the electronic apparatus.SOLUTION: The physical quantity sensor includes: a detection section 13 that outputs a detection signal; a control section 15 that converts a differential value between the detection signal and a reference value by using a predetermined conversion magnification to output a control signal. According to the physical quantity sensor, the control section is configured so that, getting a first threshold value and a second threshold value larger than the first threshold value and when the differential value is larger than the first threshold value and is smaller than the second threshold value, a conversion magnification is changed according to the magnitude of the differential value.

Description

  The present invention provides a physical quantity sensor having a detection unit that detects an input to an electronic device such as an information device capable of performing various controls by input with a simple operation, a refrigerator that controls operation by a compression load, and a washing machine. And a physical quantity sensor and an electronic device using the control method.

  Conventionally, an electronic device such as an information device that operates by detecting an input has a detection unit using a physical quantity sensor such as a pressure sensor, and is configured as shown in FIG. 5 and adjusted as shown in FIG. It had been.

  As shown in FIG. 5, the conventional physical quantity sensor includes an input device (touch panel) 1, a panel 2 made of a transparent glass substrate or the like, and a plurality of load sensors (force sensors) A to A arranged below the panel 2. And D. The four load sensors A to D are arranged at the four corners of the panel 2. The panel 2 is provided with a display area 5 at the center thereof, and a decoration area 6 is provided around the display area 5.

  The sensor output of each of the load sensors A to D is measured, and the center of the width dimension W in the X direction and the length dimension L in the Y direction is (0, 0). x, position y "is calculated.

  As shown in FIG. 6, the conventional physical quantity sensor performs an initial offset correction (step ST1) as a normal routine after initial setting, and then proceeds to a processing loop (step ST2). In the processing loop (step ST2), steps ST3 to ST9 are repeatedly performed.

  First, in step ST3, the zero point correction is updated when the absolute value of the output change amount of each load sensor A to D is equal to or less than a predetermined threshold value α during a certain measurement period.

  Next, in step ST4, the position data and the total load Z of each load sensor A to D are calculated.

  Next, in step ST5, when the absolute value | dZ / dt | of the change amount of the total load Z of each of the load sensors A to D is equal to or less than a predetermined threshold value β, each calculation data is determined to be normal, and from the threshold value β If it is too large, it is judged as abnormal and the abnormal data of high frequency noise is removed. Further, since the change amount of the total load Z of each of the load sensors A to D may be positive and negative as well as the output change amount of each load sensor, it is an absolute value when compared with the threshold value β.

  If the absolute value | dZ / dt | of the change amount of the total load Z is equal to or smaller than the predetermined threshold value β, the process proceeds to step ST6.

  Next, in step ST6, each calculation data is smoothed by moving average to remove white noise. The moving average can be calculated by averaging a plurality of continuous position data x, y and total load Z.

  Next, in step ST7, when the absolute value | Z | of the total loads of the load sensors A to D is equal to or greater than a predetermined threshold γ, it is determined that the calculated data is input by an operating body such as a finger or a pen, and the threshold If it is smaller than γ, it is determined that no input has been made, and data that has been determined not to be input with a low load is removed.

  Next, in step ST8, the first and last predetermined number of data are removed from the continuously obtained data.

  Next, in step ST9, the display screen displayed via the panel 2 of a liquid crystal display (not shown) is updated. After the screen update, the process is returned to the processing loop ST2. (Patent Document 1)

International Publication No.2012-056795

  However, in the above-described conventional physical quantity sensor disclosed in Patent Document 1, when the data is corrected, the physical quantity sensor is controlled before and after the threshold value by performing control so that the data is removed if the threshold value is not more than the threshold value, and the data is adopted if the threshold value is not less than the threshold value. The operation of the provided electronic device changed rapidly, and the user felt uncomfortable. For this reason, in the conventional control method as shown in Patent Document 1, for example, when correction such as noise removal is performed, the operation of the electronic device changes rapidly, and the user does not feel uncomfortable. There was a problem that noise could not be reduced and the user could not use information equipment comfortably.

  Therefore, an object of the present invention is to provide a method for controlling an electronic device that can be used comfortably with reduced noise with a simple configuration.

  In order to solve the above problems, a physical quantity sensor control method according to the present invention includes a detection unit that outputs a detection signal, and a control that outputs a control signal obtained by converting a difference value between the detection signal and a reference value at a predetermined conversion magnification. The controller has a first threshold and a second threshold greater than the first threshold, the difference value is greater than the first threshold, and the second When it is smaller than the threshold value, the conversion magnification is changed according to the magnitude of the difference value.

  With the above configuration, the present invention enables the difference value from the difference value to the control signal when the difference value between the detection signal output from the detection unit and the reference value is larger than the first threshold value and smaller than the second threshold value. Since the conversion magnification is changed, the electronic device can be comfortably used.

1 is an overall view of an electronic device according to an embodiment of the present invention. Block diagram of the electronic device The figure which shows the relationship of the difference value conversion magnification in one embodiment of this invention The figure which shows the relationship between the difference value and the control signal Plan view of conventional electronic equipment Flowchart showing a conventional physical quantity sensor control method

  FIG. 1 is a diagram illustrating an electronic apparatus according to an embodiment of the present invention. In the electronic device 11, the detection unit 13 is provided on the side surface of the housing 12, and when the housing 12 is distorted due to external factors such as pressing, the detection unit 13 detects the distortion, The operation of the electronic device 11 is controlled according to the amount. The electronic device 11 includes a display unit 14, and performs operations such as moving an image displayed on the display unit 14 when a press applied to the housing 12 is detected. FIG. 2 is a block diagram showing a simple configuration of the electronic device 11 according to the embodiment of the present invention. The electronic device 11 detects an input such as a pressure on the electronic device 11 and outputs a detection signal corresponding to the magnitude of the input, and the operation of the electronic device 11 by software processing when the detection signal is input. The control part 15 which outputs the signal (henceforth a control signal) which controls this, and the operation | movement part 16 which operate | moves according to a control signal are provided.

  In one embodiment of the present invention, the control unit 15 converts the detection signal by a predetermined conversion magnification by software processing and outputs a control signal, but performs similar processing by circuit processing. Also good. In the present embodiment, the physical quantity sensor 17 includes the functions of the detection unit 13 and the control unit 15 in FIG. In the present embodiment, the operation unit 16 performs application processing. However, the operation unit 16 is not limited to this as long as the electronic device 11 can be operated.

  The detection unit 13 has a beam provided with a drive unit and a monitor in which a piezoelectric body and an electrode are laminated, and a drive voltage is applied to the drive unit to vibrate the beam and monitor the vibration of the beam. It is detected by the part. The beam vibrates at a frequency of 35 kHz, but when the housing 12 is distorted, the beam expands and contracts according to the magnitude of the distortion generated in the housing 12, and the expansion and contraction changes the natural frequency of the beam. In addition, the magnitude of distortion generated in the housing 12 can be detected by detecting a change in the natural frequency.

  The control unit 15 receives the detection signal output from the detection unit 13 and outputs a control signal based on the detection signal, and the operation unit 16 operates the electronic device 11 based on the control signal. Since the beam of the detection unit 13 is constantly oscillating, the detection signal is always input to the control unit 15, and the natural frequency of the beam without input to the electronic device 11 is 35 kHz. The reference value is used.

  In the control unit 15, there is an input by pressing or the like in the electronic device 11, and a difference (hereinafter referred to as a difference value) between a detection signal and a reference value when the natural frequency of the beam is changed by this input is taken, and this difference A control signal corresponding to the value is generated. The operation unit 16 causes the electronic device 11 to perform an operation such as moving an image displayed on the display unit 14 or changing a volume of music emitted from the electronic device 11 according to the magnitude of the control signal.

  Next, a control method of the physical quantity sensor 17 of the present embodiment will be described.

  The control unit 15 changes the ratio between the magnitude of the control signal and the magnitude of the difference value (hereinafter referred to as the conversion magnification) in accordance with the difference value, and converts the difference value with this conversion magnification for control. The signal is generated, that is, the size of the control signal is determined by the difference value × conversion magnification. The magnitude of the control signal is determined by multiplying the magnitude of the difference value by the conversion magnification. The control unit 15 has a first threshold value and a second threshold value larger than the first threshold value, and changes the conversion magnification in the following three states.

  (1) When the difference value is equal to or less than the first threshold value.

  (2) When the difference value is larger than the first threshold value and smaller than the second threshold value.

  (3) When the difference value is greater than or equal to the second threshold value.

  FIG. 3 shows the relationship between the difference value and the conversion magnification. FIG. 4 shows the relationship between the difference value and the control signal.

  As shown in FIG. 3, in one embodiment of the present invention, the first threshold is 30 Hz, the second threshold is 60 Hz, the conversion magnification is 0.5 in the region (1), In the area, the conversion magnification is changed to be proportional to the difference value, and in the area (3), the conversion magnification is 2. Here, in one embodiment of the present invention, the maximum influence of noise due to external factors on the detection signal is 30 Hz.

Also, as shown in FIG. 4, in one embodiment of the present invention,
In the area (1), since the influence of noise is 30 Hz at the maximum, the detection signal is different from the reference value due to noise and a difference value is generated even though there is no input by the user to the electronic device 11. There is. Here, in the area (1), since the conversion magnification is set to 0.5, correction is performed so that the control signal becomes smaller than the difference value even when noise is added to the detection signal due to an external factor or the like. ing. For this reason, noise is also multiplied by 0.5 and output as a generated signal, so that the influence of noise can be reduced. Further, in the area (1), it may be set such that input to the electronic device 11 is not accepted (for example, the conversion magnification is set to 0), thereby preventing malfunction of the electronic device 11 due to noise. be able to.

  In the area (2), the conversion magnification is changed according to the difference value from the conversion magnification 0.5 at the first threshold value to the conversion magnification 2 at the second threshold value. As shown in FIG. 3, in the embodiment of the present invention, the conversion magnification is 0.5 in the area (1), and the conversion magnification is 2 in the area (3). It is necessary to change the conversion magnification from 0.5 to 2. However, in the area (2), when the difference value suddenly changes from 0.5 to 2 with a certain value as a boundary, the image of the electronic device 11 suddenly moves greatly or the volume suddenly increases. End up. For this reason, when the user inputs with a force that causes the magnification to change abruptly or the magnitude of noise changes, the electronic device 11 performs an unexpected operation of the user. It becomes very difficult to use. Here, as the difference value increases in the area (2), the conversion magnification is changed linearly, so that the image can be operated slightly or the volume can be changed slightly. It is possible to prevent an operation such as a large movement or a sudden change in volume, and the user can use the electronic device 11 without feeling uncomfortable.

  In the region (3), the influence of noise, which is a region where the difference value is very large compared to noise (30 Hz or less), is small. For this reason, the dynamic range of the control signal can be increased by setting the conversion magnification to 2 so that the control signal becomes larger than the difference value. For this reason, the detection sensitivity can be improved in the region (3), and the electronic device 11 can be controlled more precisely.

  As described above, the physical quantity sensor 17 according to the embodiment of the present invention generates the control signal by changing the conversion magnification in the areas (1), (2), and (3). For this reason, when the influence of the noise in the area (1) is large, the influence of the noise is reduced, and when the influence of the input of the user of the electronic device 11 of (3) is larger, the dynamic range of the control signal is increased. In the region between (1) and (3), the conversion magnification can be changed without making the user feel uncomfortable. By this control method, it is possible to provide the electronic device 11 that can reduce malfunctions of the electronic device 11 and can be used comfortably with high sensitivity.

  In the embodiment of the present invention, the conversion magnification of the area (1) is 0.5 and the conversion magnification of the area (3) is 2. However, the present invention is not limited to this. For example, the area (1) The conversion magnification of 0.1 may be 0.1, the conversion magnification of the area (3) may be 5, and the conversion magnification in each area depends on the use, conditions, etc. of the electronic device to which the embodiment of the present invention is applied. You may change suitably.

  In addition, the first threshold value is 30 Hz and the second threshold value is 60 Hz. However, the present invention is not limited to this. In particular, it is particularly preferable that the first threshold value is a maximum noise value assumed for the electronic device, and the second threshold value is a value that makes the input equal to the assumed noise value, that is, a value that is twice the first threshold value. It is.

  In the embodiment of the present invention, the conversion magnification is linearly changed in the region (2). However, the present invention is not limited to this, and the use and conditions of the electronic apparatus to which the embodiment of the present invention is applied In addition, for example, it may be changed to be a quadratic function.

  In one embodiment of the present invention, a change in frequency is detected, a control signal is generated based on this change in frequency, and the electronic device 11 is controlled by this control signal. For example, the detection signal may be obtained using a change in voltage or the like.

  In one embodiment of the present invention, the detection signal obtained by the detection unit 13 is corrected to a control signal as it is, and the electronic device 11 is operated using the correction signal. Even if is used, the effect of the embodiment of the present invention can be obtained.

  The electronic device control method of the present invention detects an input to the electronic device by a detection unit, outputs a detection signal corresponding to the input, and changes a correction method in the control unit according to the output of the detection signal, Since the influence of noise on an electronic device can be reduced and detection accuracy can be improved, it is particularly useful for digital cameras, notebook PCs, portable game machines, mobile phones, personal digital assistants (PDAs), smartphones, and the like. Moreover, it is useful also for the electronic device which controls operation | movement by the distortion which arose in strain generating bodies, such as a refrigerator and a washing machine. Further, the electronic device control method of the present invention changes the correction change rate in the control unit in accordance with the output of the detection signal, so that it can reduce a sense of incongruity with respect to user input, and is particularly useful for an input device. It is.

DESCRIPTION OF SYMBOLS 11 Electronic device 12 Case 13 Detection part 14 Display part 15 Control part 16 Operation part 17 Physical quantity sensor

Claims (6)

A control method for a physical quantity sensor, comprising: a detection unit that outputs a detection signal; and a control unit that outputs a control signal obtained by converting a difference value between the detection signal and a reference value at a predetermined conversion magnification. The unit has a first threshold and a second threshold greater than the first threshold;
When the difference value is larger than the first threshold and smaller than the second threshold;
A physical quantity sensor control method for changing the conversion magnification according to the magnitude of the difference value. When the difference value is less than or equal to the first threshold value,
The method of controlling a physical quantity sensor according to claim 1, wherein the conversion magnification is smaller than 1. When the difference value is greater than or equal to the second threshold value,
The method of controlling a physical quantity sensor according to claim 1, wherein the conversion magnification is larger than one. The conversion magnification is
2. The physical quantity sensor control method according to claim 1, wherein the physical quantity sensor is proportional to the magnitude of the difference value. A physical quantity sensor comprising: a detection unit that outputs a detection signal; and a control unit that outputs a control signal obtained by converting a difference value between the detection signal and a reference value at a predetermined conversion magnification,
The control unit has a first threshold value and a second threshold value larger than the first threshold value,
When the difference value is larger than the first threshold and smaller than the second threshold;
A physical quantity sensor that changes the conversion magnification according to the magnitude of the difference value. The physical quantity sensor according to claim 5;
An electronic apparatus further comprising an operation unit that performs an operation according to the control signal.

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