JP2005352239A - Personal digital assistant equipment with camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide personal digital assistant equipment with a camera capable of detecting camera movement with good accuracy and preventing the degradation in sharpness due the camera movement even when the output of an acceleration detecting means includes much noise. <P>SOLUTION: The acceleration detecting means 101 detects the acceleration component added on a casing and the rotational component (inclination) of the casing. A camera movement estimating means 102 reduces the noise component from the output of the acceleration detecting means and estimates the occurrence of the camera movement. When a photographing start command is inputted from a shutter release 103 to a delay amount control means 104, the control means delays the photographing start command and outputs the same until the camera movement ceases based on the output of the camera movement estimating means 102. When the photographing start command is inputted to a camera module 105, the module stores the video signal imaged through an optical lens into a memory. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a camera-equipped mobile phone that prevents deterioration in image quality due to camera shake.

  Conventionally, when hand-held shooting is performed with a camera, there has been a problem that camera shake is likely to occur when the holding posture of the camera is unstable or the shutter speed is slow because the subject is dark.

  In particular, when downsizing is a priority, such as a camera-equipped mobile phone, there is a problem in that the shutter speed becomes slow due to hardware limitations that the brightness of the lens and the sensitivity of the image sensor cannot be taken sufficiently. In addition, the problem of software is more likely to cause camera shake, such as the user often taking pictures with one hand because it has become smaller and lighter.

  In order to prevent such camera shake, when camera shake has already occurred due to camera shake, the size of the camera shake is detected as an angular velocity or angular acceleration applied to the camera. Thus, an idea of a shake correction device has been realized in which the correction lens is displaced in a direction opposite to the direction in which the shake occurs to prevent the occurrence of image blur.

  The history of this technology is quite old, and it has already been installed in anti-vibration cameras and home movies on news helicopters. However, since this device requires a drive control system such as a correction lens, it is incompatible with the demand for miniaturization of the camera. Especially, mounting on a camera-equipped mobile phone has a large problem in both size and cost. .

  Therefore, the invention disclosed in Patent Document 1 includes an angular velocity detection unit that detects an angular velocity applied to the camera. When the angular velocity detected by the angular velocity detection unit exceeds a certain value, the shutter operation is disabled, and the angular velocity is constant. The shutter operation can be performed when the value is less than the value or when the value reaches a certain value after exceeding a certain value. With such a configuration, it is not necessary to drive the correction lens, so that the drive control system can be omitted.

Japanese Patent No. 2603871

  However, in general, the output of the angular velocity detection means includes a lot of random noise. For this reason, in the case of small camera shake, it is difficult to distinguish between output due to noise and output due to camera shake, and it is difficult to accurately detect camera shake.

  The present invention has been made in view of the above-described problems, and even if the output of a means for detecting a camera shake such as an angular velocity detecting means contains a lot of noise, the camera shake is accurately detected. A mobile terminal device with a camera that can detect well and prevent camera shake is provided.

  The present invention relates to a mobile terminal device with a camera that starts shooting in response to a shooting start command commanded by a user, the acceleration detecting means for detecting an acceleration applied to a housing of the mobile terminal device, and the acceleration detecting means Camera shake estimation means for estimating camera shake by performing predetermined processing including processing for reducing the influence of noise included in the output, and when the shooting start command is input, Delay amount control means for delaying and outputting the imaging start command based on the output of the estimation means.

  Since the above configuration is provided, the camera shake is estimated by reducing the noise included in the output of the acceleration detecting means for detecting the camera shake. Then, after the camera shake is converged, an imaging start command is output.

  For this reason, even when a lot of noise is included in the output of the acceleration detection means, it is possible to accurately detect camera shake and prevent camera shake.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a configuration of a camera-equipped mobile phone (camera-equipped mobile terminal device) according to the present embodiment. The output of the acceleration sensor (acceleration detection means) 101 is input to the camera shake estimation means 102. The output of the camera shake estimation unit 102 is input to the delay amount control unit 104. The output of the shutter release 103 is input to the delay amount control means 104. The output of the delay amount control means 104 is input to the camera module 105.

  The acceleration sensor 101 detects the acceleration applied to the housing and outputs it to the camera shake estimation means 102. The camera shake estimation unit 102 estimates the occurrence of camera shake by reducing a noise component included in the output of the acceleration sensor 101 and outputs the estimated result to the delay amount control unit 104.

  The delay amount control unit 104 outputs a timing to output a shooting start command to the camera module 105 based on the output of the camera shake estimation unit 102 when a shooting start command is input from the shutter release 103 to which the user commands shooting start. Control. The camera module 105 captures an image based on an imaging start command from the delay amount control unit 102.

  The acceleration sensor 101 includes a lateral acceleration sensor 101a that is installed in the horizontal direction and detects acceleration, and a vertical acceleration sensor 101b that is installed in the vertical direction and detects acceleration. Here, the horizontal direction indicates a direction horizontal to the ground surface, and the vertical direction indicates a direction perpendicular to the ground surface.

  Further, the camera shake estimation unit 102 estimates camera shake based on the output of the lateral acceleration sensor 101a, and estimates camera shake based on the output of the horizontal direction camera shake estimation unit 102a and the output of the vertical acceleration sensor 101b. In addition, it is constituted by the vertical camera shake estimation means 102b for output. Here, the acceleration sensor 101 and the camera shake estimation means 102 may be one set or a plurality of sets.

  Next, the acceleration sensor 300 used in the present embodiment will be described in detail. Unlike the angular acceleration sensor using Coriolis force, the acceleration sensor 300 according to the present embodiment has a feature of high impact resistance because it does not have a movable part.

  FIG. 2 shows a top view of the acceleration sensor 300. The acceleration sensor 300 is a biaxial acceleration sensor that detects acceleration generated in the horizontal direction in the drawing and acceleration generated in the vertical direction. Here, when one acceleration sensor 300 is attached to the mobile phone, the acceleration sensor 300 corresponds to the acceleration sensor 101 shown in FIG. The horizontal axis in the figure corresponds to the lateral acceleration sensor 101a, and the vertical axis in the figure corresponds to the vertical acceleration sensor 101b. When two acceleration sensors 300 are used, the two acceleration sensors 300 are combined to constitute the acceleration sensor 101 shown in FIG. The acceleration sensor 300 installed in the horizontal direction corresponds to the horizontal acceleration sensor 101a, and the acceleration sensor 300 installed in the vertical direction corresponds to the vertical acceleration sensor 101b.

  An opening 305 is provided in a silicon substrate (substrate) 301. A heater (heating means) 303 is disposed at a substantially central portion of the opening 305. Two rectangular temperature sensors 302 are arranged so as to sandwich the heater 303 from the left and right when viewed from above. Further, two rectangular temperature sensors 302 are arranged so as to sandwich the heater 303 vertically when viewed from above.

  One end of the temperature sensor 302 is joined to a mounting portion 307 disposed substantially at the center of the opening 305, and the other end is disposed on the silicon substrate 301. A heater 303 is joined to the lower surface of the attachment portion 307. The temperature sensor 302 is formed of, for example, a thermocouple, and an output terminal 306 for taking out a signal is provided at the other end of each temperature sensor 302.

  FIG. 3 is a view corresponding to the cross-sectional view taken along line A1-A1 of FIG. As shown in FIG. 3, the silicon substrate 301 is covered with a resin 309, and a hemispherical cavity 304 is provided inside the resin 309. Air is confined in the cavity 304. 2 corresponds to a top view of the B1-B1 line in FIG.

  Next, the operation of the acceleration sensor 300 will be described with reference to FIG. The acceleration sensor 300 can detect inclination (rotation component) and parallel acceleration (acceleration component).

  First, when the air confined in the cavity 304 is warmed by the heater 303, the warmed air becomes light. When the acceleration is applied in the left direction in the figure, the warmed air moves in the left direction. Conversely, when acceleration is applied in the right direction in the figure, the warmed air moves in the right direction. Accordingly, there is a difference in temperature distribution between the left and right regions of the acceleration sensor 300. By detecting the temperature distribution difference by the temperature sensor 302, the direction and magnitude of the acceleration can be detected.

  Furthermore, the inclination can be detected using the gravitational acceleration applied to the acceleration sensor 300. For example, when it is tilted to the right in FIG. 3, the warmed air moves to the left. The slope can be measured by comparing the left and right temperature distributions.

  Next, the detection output of the acceleration sensor 300 will be described with reference to FIG. FIG. 4 is a diagram illustrating the output value of the acceleration sensor 300 with respect to the tilt for the acceleration sensor 300 in which the sensor surface (silicon surface: the surface of the silicon substrate 301) is installed horizontally.

  In the horizontal state, the output is zero (point M) because there is no difference in temperature distribution between the left and right of the acceleration sensor 300. As it is tilted to the right, the gradually warmed air 308 moves to the left, causing a difference in temperature distribution between the left and right regions, and the sensor output gradually increases (point N). When it is vertical, the difference in temperature distribution is the largest on the left and right, and the sensor output is the largest. On the contrary, if the sensor gradually tilts from the center to the left, the sensor output value gradually increases in the negative direction (point L). From the above, the output value of the acceleration sensor 300 has a relationship of sin θ with respect to the inclination angle θ of the acceleration sensor 300.

  Similarly, when the acceleration sensor 300 is rotated 90 degrees so that gravity is applied parallel to the sensor surface (silicon surface) as shown in FIG. 5, the acceleration sensor 300 with respect to the inclination angle θ of the acceleration sensor 300. Output of cos θ.

  As can be seen from FIGS. 4 and 5, the output change S1 when tilted by the same tilt angle θ (for example, the angle corresponding to the point N, the point P) is larger when the sensor surface is placed horizontally. That is, when installed horizontally, a large output is generated with a slight inclination compared to when installed vertically. Therefore, in order to increase the sensitivity with respect to the tilt of the acceleration sensor 300, the silicon surface is mounted so as to be horizontal during shooting, and conversely, to decrease the sensitivity with respect to the tilt of the acceleration sensor 300, the silicon surface is vertical during shooting. It is good to attach to.

  If the acceleration component applied to the acceleration sensor 300 is only gravitational acceleration, in principle, the angular velocity in the rotational direction can be calculated by differentiating the inclination. However, in general, movement such as shake that occurs when operating the shutter release has an acceleration component, so that the rotation component and the acceleration component are detected together. Therefore, when it is desired to detect the acceleration component predominantly when shooting in the horizontal direction, as described above, the gravitational acceleration direction and the mounting direction of the acceleration sensor 300 (silicon surface of the acceleration sensor 300) are made parallel. As a result, it is possible to detect the rotational component predominantly while reducing the detection of the rotational component.

  An amount obtained by combining the acceleration component and the rotation component detected by the acceleration sensor 300 may be simply referred to as “acceleration”.

  Next, the operation of the camera shake estimation unit 102 that estimates camera shake based on the output of the acceleration sensor 101 will be described with reference to FIGS.

  FIG. 6 is a diagram illustrating an example of the output of the acceleration sensor 101. The vertical axis represents the output value (sensor output value) from the acceleration sensor 101, and the horizontal axis represents time. Here, the input from the acceleration sensor 101 takes a continuous value, but the camera shake estimation means 102 obtains the input from the acceleration sensor 101 every predetermined minute time. Therefore, the sensor output value in FIG. 6 changes discontinuously with respect to time. As described above, in the output of the acceleration sensor 101, the inclination of the acceleration sensor 101 and the acceleration component applied to the acceleration sensor 101 are combined. Further, there is a random noise component that is more thermal noise. In FIG. 6, the sensor output value fluctuates between −2 and −4 due to the noise component with the sensor output value −3 as the center. For example, the portions indicated by N1 and N2 in FIG. 6 indicate random noise, and between N1 and N2, the change in sensor output to be detected and the sum of random noise are indicated.

  Differentiating the output of the acceleration sensor 101 with respect to time makes it possible to detect the rate of change between the rotation component and the acceleration component. However, when a random noise component exists, a simple differentiation includes a large noise component. In order to reduce the influence of such noise and determine the timing at which the sensor output value changes greatly, the camera shake estimation unit 102 performs the following processing based on the past sensor output value.

  First, as shown in FIG. 7, a moving average value of sensor output values in the past n times (in this example, 5 times) is calculated. As a result, a waveform in which the influence of a random noise component is reduced can be obtained. However, since a change in the waveform to be detected is delayed, the determination using only this waveform results in detection delayed from the time of occurrence of camera shake. Therefore, an absolute difference value from the current sensor value is calculated as shown in FIG. By performing such processing, it is possible to obtain the difference between the current output value and the average value of the past n sensor output values not including the current output value. That is, it is possible to calculate how much the current output value has changed with respect to the average value of the past n times. Since the random noise component does not have a large change rate from the average value, the noise component can be reduced by performing such processing.

  As described above, the camera shake estimation unit 102 estimates a camera shake in which the sensor output value changes greatly by reducing the noise component.

  Here, when the camera shake estimation means 102 is constituted by the horizontal camera shake estimation means 102a and the vertical camera shake estimation means 102b, the horizontal camera shake estimation means 101a and the vertical camera shake estimation means 102b, respectively. It is calculated independently from the output of.

  The camera shake estimation unit 102 outputs the difference absolute value calculated as described above to the delay amount control unit 104.

  In addition, although the process which calculates the difference with a moving average was shown as an example of the method of reducing a noise component, what kind of process may be sufficient if a noise component can be reduced based on the past sensor output value.

Next, the operation of the delay amount control means 104 will be described with reference to FIG. A broken line R shown in FIG. 8 indicates the time when the imaging start command is input to the delay amount control unit 104.
When an imaging start command is input from the shutter release 103, the delay amount control unit 104 monitors the absolute difference value input from the camera shake estimation unit 102, and outputs the past m times (eight times in this example). If a threshold value s (1.4 in this example) is greater than or equal to the threshold value s, camera shake has occurred, and if all are less than the threshold value, it is estimated that camera shake has converged. For example, in the case of FIG. 8, it is determined that camera shake has occurred in the period D and the camera shake has converged at the timing of point E. Then, a shooting start command is output to the camera module 105 at the timing of point E.

  That is, when the shooting start command is input, the delay amount control unit 104 delays and outputs the shooting start command until the camera shake is converged based on the output of the camera shake estimation unit 102.

  Here, the sampling number m and the threshold value s can be determined by taking a large number of shots with a large number of people according to the assumed holding method and style. It is possible to obtain empirically as an appropriate parameter in the relationship).

  In the example of FIG. 8, it is necessary to set the sampling count m to 5 or more so as not to erroneously determine that the blur has converged when the value decreases to 0.5 after the maximum value exceeding 3. In order to prevent an erroneous determination of blur convergence, m is preferably as large as possible. However, since the delay time of shooting is increased and the operability of the photographer is deteriorated, m = 5 is set as a minimum value at which no erroneous determination occurs. be able to.

  The camera module 105 includes an optical lens (not shown), an image sensor, a signal processing circuit, a memory, and the like. When a shooting start command is input, the camera module 105 inputs a video signal imaged through the optical lens from the image sensor, converts the video signal into a format such as JPEG in a signal processing circuit, and generally stores the memory. Save to.

  Next, a method for attaching the acceleration sensor in the present embodiment will be described.

  First, the relationship between the type of camera shake and the resulting image blur amount will be described with reference to FIGS. FIG. 9 is a diagram for explaining the arrangement of an orthogonal coordinate system used in the following description. An origin of an orthogonal coordinate system is set at the center of an image sensor (not shown) inside the camera 201, and the optical axis of the camera is set as the Z-axis direction. Let the horizontal direction of the camera 201 be the X-axis direction orthogonal to the Z-axis. The vertical direction of the camera 201 is taken as the X axis and the Y axis perpendicular to the Z axis.

  10 to 13 are diagrams for explaining the amount of image blur that occurs when camera shake occurs in a direction parallel to the X-axis direction, the Y-axis direction, and the Z-axis direction. FIG. 10 shows a state where there is no camera shake. L1 represents the distance from the imaging lens to the subject O, and L2 represents the distance from the imaging lens to the imaging device.

  FIG. 11 shows a case where the camera body moves in parallel in the X axis direction (horizontal direction) by x. The image blur amount Δx on the image sensor is expressed by Δx = x · L2 / L1. Therefore, when L1 >> L2, Δx can be almost ignored. FIG. 12 shows a case where the camera body moves in parallel in the Y-axis direction (vertical) by y. The image blur amount Δy on the image sensor is also expressed by Δy = y · L2 / L1. Therefore, when L1 >> L2, Δy can be almost ignored as well. FIG. 13 shows a case where the camera moves in parallel in the Z-axis direction (optical axis direction) by z. In this case, the distance L1 to the subject O changes to L1 + z and causes blurring. However, when L1 >> L2, the magnitude of the blur and image blur amount hardly changes and can be ignored. As described above, camera shake occurring in a parallel direction can hardly ignore the image blur amount in all of the X-axis direction, the Y-axis direction, and the Z-axis direction, and is not a problem.

  On the other hand, FIGS. 14 to 16 show the amount of image blur that occurs when a camera shake of a rotational component occurs around the X, Y, and Z axes. FIG. 14 shows a case where the camera 201 rotates about the X axis by an angle θx. The rotation around the X axis causes image blur in the Y axis direction on the image sensor. The image blur amount Δy is expressed by Δy = L2 · Tanθx.

  FIG. 15 shows a case where the camera 201 rotates about the Y axis by an angle θy. The rotation around the Y axis causes image blur in the X axis direction on the image sensor. The image blur amount Δx is expressed by Δx = L2 · Tanθy. FIG. 16 shows a case where the camera 201 rotates about the Z axis by an angle θz. At this time, the image on the image sensor is also rotated by the angle θz. Thus, image blur due to rotation around the X, Y, and Z axes directly affects image blur regardless of the distance L1 from the imaging lens to the subject O.

  For these reasons, in order to accurately detect and correct or prevent the amount of camera shake, it is necessary to detect the rotation amount or rotation speed around the X, Y, and Z axes. In general, the rotational speed (angular speed) can be accurately detected regardless of the acceleration applied to the casing such as gravity by using the Coriolis force. Therefore, in the prior art, an angular velocity sensor having a movable part for detecting Coriolis force is often used.

  Next, how to hold the camera-equipped mobile phone 401 at the time of shooting and camera shake that tends to occur at the time of shooting will be described.

  As a form of taking a photograph using the camera-equipped mobile phone 401, as shown in FIG. 17, a case where a half-folded casing is opened and held in the vertical direction and the “button A” in the center is pressed, or the photograph is taken. In general, the camera is photographed by closing the casing and holding it in the horizontal direction and pressing the “button B” on the side portion. In general, when the angle of view is determined for a subject and a button is pressed, vibration of the housing of the camera-equipped mobile phone 401 occurs in accordance with the button operation.

  Therefore, when shooting as shown in FIG. 17, pressing the “button A” causes a large component to rotate around the X axis described in FIG. In the case of taking a picture as shown in FIG. 18, by pressing “button B”, a component that rotates around the Z-axis described in FIG. 16 is greatly generated. Then, if the image is taken while the vibration is not settled, image blur occurs in the taken image. Therefore, the vibration after the button is pressed down can be detected by detecting the acceleration components around the X axis and the Z axis in FIG.

  As described above, in the case of camera shooting, there are horizontal position shooting and vertical position shooting, in which the subject is held in the horizontal direction and the subject is shot horizontally, or the subject is held in the vertical direction and the subject is shot vertically. Therefore, when one acceleration sensor 300 is used, the acceleration sensor 300 is attached in parallel to the XY plane so that acceleration components in the X-axis direction (vertical direction) and the Y-axis direction (lateral direction) can be detected. In other words, the acceleration sensor 300 is mounted so that the silicon substrate 301 is vertical (see FIG. 17). Here, since the acceleration sensor 300 corresponds to the acceleration sensor 101 of FIG. 1, the acceleration sensor 101 is illustrated in FIG. 17.

  When mounted in this way, in the case of horizontal position shooting rotated 90 degrees to the right (see FIG. 18), the X-axis is set to the vertical direction and the Y axis is set to the horizontal direction, so that output similar to that for vertical position shooting is performed. Produce. Since the acceleration sensor 300 produces the same output in both the vertical position shooting and the horizontal position shooting, the delay amount control unit 104 prepares a plurality of parameters such as a threshold value, and the vertical position shooting and the horizontal position shooting are performed. And no need to switch. Here, the acceleration sensor 300 corresponds to the acceleration sensor 101 shown in FIG.

  Further, when two acceleration sensors 300 are mounted, as shown in FIG. 19, one acceleration sensor 300 is horizontally mounted on the XZ plane as a lateral acceleration sensor 101a. That is, the acceleration sensor 300 is mounted so that the silicon substrate 301 is horizontal. The other acceleration sensor 300 is mounted horizontally on the YZ plane as the vertical acceleration sensor 101b. In the case of vertical position shooting (see FIG. 20), the horizontal acceleration sensor 101a is set as the vertical acceleration sensor 101b, and the vertical acceleration sensor 101b is set as the horizontal acceleration sensor 101a. By doing so, it is not necessary to prepare a plurality of parameters such as a threshold value in the delay amount control unit 104 and switch between vertical position shooting and horizontal position shooting as in the case of the single acceleration sensor described above.

  Furthermore, when one acceleration sensor 300 is used, the output of the rotation component cannot be increased. For example, in the case of FIG. 17, the lateral component can largely detect the acceleration component in the X-axis direction and the rotation component around the Z-axis. However, since the vertical direction (Y-axis) component is horizontal with respect to the gravitational acceleration as shown in FIG. 5, a large rotation component around the X-axis cannot be output.

  When a plurality of acceleration sensors 300 are used, a large rotational component around the X axis can be output by the acceleration sensor 101a (see FIG. 19). In this way, both the rotation component and the acceleration component can be output greatly, and camera shake can be detected with high accuracy.

  Next, the operation of the camera-equipped mobile phone configured as described above will be described. The acceleration sensor 101 constantly detects the acceleration component and the rotation component applied to the housing in the vertical direction and the horizontal direction, and continues to output them to the camera shake estimation unit 102.

  The camera shake estimation unit 102 calculates an average value (moving average value) of sensor output values up to a certain past time not including the time when the output value is input at each time when the sensor output value is input. Then, the difference between the sensor output value and the moving average value at each time point is calculated and continuously output to the delay amount control means 104.

  When the user presses the shooting start button in this state, a shooting start command is input from the shutter release 103 to the delay amount control means 104. Based on the output from the camera shake estimation unit 102, the delay amount input unit 104 determines whether or not a camera shake has occurred according to the procedure described above. When it is determined that the camera shake has subsided, a shooting start command is output to the camera module 105. When the imaging start command is input, the camera module 105 stores the video signal imaged through the optical lens in a memory.

  Since the image shot in this way needs to be determined m times in the past in the delay amount control means 104, at least m times from when the shutter release 103 is pressed until the actual shooting start command is output. Sampling time is required. For example, if one sampling period is 10 msec and m = 10, a delay of 100 msec occurs. Therefore, it is possible to realize shooting without camera shake although the photo opportunity is delayed by at least 0.1 second. If it is absolutely important to take a photo, you can turn off this function and fix the housing to prevent camera shake, or increase the amount of light to increase the shutter speed.

  As described above, in the present invention, the vibration (acceleration component and rotation component) generated by pressing the shutter release button is detected by the acceleration sensor 101, and the image is taken after the vibration is settled. Therefore, it is possible to provide a camera-equipped mobile phone system that can prevent blurring without requiring a correction mechanism such as a blur correction device.

  In addition, since the noise component included in the acceleration sensor 101 is reduced by the camera shake correction unit 102 and the occurrence of the camera shake is estimated, the camera shake can be prevented with high accuracy.

  Furthermore, by differentiating the output of the acceleration sensor 101, the DC component of inclination detection can be removed, and a change in acceleration applied to the acceleration sensor 101 can be detected as a center.

  By providing the acceleration sensor 300 for both the vertical position shooting and the horizontal position shooting and attaching the silicon surface so that the silicon surface is horizontal at the time of each shooting, both the rotation component and the acceleration component generated by the shooting are greatly output, Detection accuracy can be increased.

  Further, the conventional technique requires a general angular acceleration sensor to detect the size of camera shake. Such an angular acceleration sensor uses the Coriolis force generated by a vibrating tuning fork, and requires, for example, a gyro signal detection unit in which a bimorph is arranged in a T shape, a tuning fork drive circuit, a signal processing circuit, etc. Due to the presence of the movable part, there is a problem that it is difficult to mount in a camera-equipped mobile phone that is expensive and has low impact resistance, and that requires low price and high impact resistance.

  In the present embodiment, since the acceleration sensor 300 is not an angular velocity sensor using Coriolis force as an acceleration sensor but has no movable part, it is possible to realize a low-priced and small impact-resistant mobile phone system with a camera.

  Furthermore, it is not necessary to switch parameters such as the threshold value of the delay amount control means 104 in the subsequent stage by attaching the silicon surface so that the vertical surface and the horizontal position shooting are both vertical with one acceleration sensor 300. Can do.

  As an application example of the present invention, a camera-equipped mobile terminal device, especially a mobile phone with a camera that is highly likely to be photographed with one hand because of its small size and light weight, and has high demands for low price, downsizing, and impact resistance. Applicable to.

1 is a block diagram illustrating a configuration of a first embodiment. 2 is a top view of the acceleration sensor used in Embodiment 1. FIG. 2 is a cross-sectional view of an acceleration sensor used in Embodiment 1. FIG. It is a figure for demonstrating the relationship between the attachment direction of the acceleration sensor used for Embodiment 1, and a sensor output. It is a figure for demonstrating the relationship between the attachment direction of the acceleration sensor used for Embodiment 1, and a sensor output. FIG. 3 is a diagram showing a sensor output of an acceleration sensor used in the first embodiment. It is a figure which shows the moving average of a sensor output. It is a figure which shows the difference absolute value of a sensor output and a moving average. It is a figure for demonstrating the coordinate system set to the camera. It is a figure for demonstrating the relationship between the parallel movement component of camera shake, and image blur. It is a figure for demonstrating the relationship between the parallel movement component of camera shake, and image blur. It is a figure for demonstrating the relationship between the parallel movement component of camera shake, and image blur. It is a figure for demonstrating the relationship between the parallel movement component of camera shake, and image blur. It is a figure for demonstrating the relationship between the rotation component of camera shake, and image blur. It is a figure for demonstrating the relationship between the rotation component of camera shake, and image blur. It is a figure for demonstrating the relationship between the rotation component of camera shake, and image blur. It is a figure which shows the shutter release of a general mobile phone with a camera, and the direction of the vibration by it. It is a figure which shows the shutter release of a general mobile phone with a camera, and the direction of the vibration by it. It is a figure for demonstrating how to attach an acceleration sensor. It is a figure for demonstrating how to attach an acceleration sensor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Acceleration sensor, 102 Camera shake estimation means, 103 Shutter release, 104 Delay amount control means, 105 Camera module.

Claims (7)

A mobile terminal device with a camera that starts shooting in response to a shooting start command given by a user,
Acceleration detecting means for detecting acceleration applied to the casing of the mobile terminal device;
A camera shake estimation unit that estimates a camera shake by performing a predetermined process including a process of reducing an influence of noise included in the output on the output of the acceleration detection unit;
When the shooting start command is input, based on the output of the camera shake estimation unit, a delay amount control unit that delays and outputs the shooting start command;
A mobile terminal device with a camera, comprising:   2. The camera-equipped mobile terminal device according to claim 1, wherein the process of reducing the influence of noise is a process based on a past output value of the acceleration detection means.   2. The camera according to claim 1, wherein the process of reducing the influence of the noise is a process of calculating a difference value between a current output value of the acceleration detection means and a moving average value of past output values. Mobile terminal device with.   The camera-equipped mobile terminal device according to claim 1, wherein the acceleration detection unit has no movable part. The acceleration detecting means includes
A gas sealed in a cavity provided on the substrate;
Heating means for partially heating the gas;
A temperature sensor for detecting the temperature distribution of the gas,
The mobile terminal device with a camera according to claim 4, wherein acceleration is detected based on an output of the temperature sensor. A plurality of acceleration detecting means;
In either of the vertical position shooting in which the case is taken vertically or the horizontal position shooting in which the case is taken horizontally, the substrate of at least one of the acceleration detection means is horizontal. 6. The camera-equipped mobile terminal device according to claim 5, wherein an acceleration detection unit is attached to the housing. The acceleration detection means is attached to the casing so that the substrate is vertical in either of the vertical position shooting in which the case is taken vertically or the horizontal position photography in which the case is taken horizontally. The camera-equipped mobile terminal device according to claim 5.

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