JP2004184817A - Portable information terminal device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent damage, burning, etc., of a camera mounted on a portable telephone set or the like and to enable a high quality picture to be photographed by preventing a phenomenon in which a photographed picture grows dim, for example. <P>SOLUTION: In the structure with a device body 10 that has a photographic window 14 and a camera 20 that is arranged inside the device body 10 and is provided with a lens 21 and a CCD 22 for photographing an object; a light-shielding blade 23 is disposed behind the photographic window 14 on the object side from the CCD 22 and the lens 21, and is opened/closed by an electromagnetic actuator 24 in accordance with the photographing and non-photographing mode. As a result, troublesomeness of opening/closing operation is eliminated, the light-shielding blade 23 can be used as a barrier in a non-photographing time and as a mechanical shutter in a photographing time. Damage due to burning or the like of the CCD and the color degradation of a color filter, for example, can be prevented, and a high quality picture can be obtained. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a portable information terminal device such as a mobile phone or a portable personal computer (PDA), and more particularly to a portable information terminal device provided with a camera capable of photographing an operator or a surrounding scenery.
[0002]
[Prior art]
2. Description of the Related Art In recent years, portable information terminal devices such as mobile phones and portable personal computers capable of transmitting and receiving image signals have been developed. For example, as a mobile phone equipped with a camera (so-called mobile camera), a shooting window is provided in the main body, and a camera including a lens and a CCD for taking a digital image is arranged inside the main body. In order to protect a lens or an image sensor, a light shielding cover is slidably provided on a main body so that a photographing window can be manually opened and closed (see, for example, Patent Document 1). ).
[0003]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2000-332871
[Problems to be solved by the invention]
By the way, in the above-mentioned conventional mobile phone, when shooting with a camera, the operator has to slide the cover to open the shooting window, which makes the operation cumbersome. In some cases, the image sensor is held open, and a strong light beam may enter through the imaging window, causing damage or burning of the image sensor, or fading of a color filter on the front surface of the image sensor.
[0005]
Further, in the above-described conventional mobile phone, the exposure time when shooting with a camera is defined only by an on / off operation of power supply to an image sensor, that is, only by an electronic shutter. Therefore, when the amount of light (luminance) of the subject is large (high luminance), simply operating the electronic shutter does not sufficiently discharge the charges accumulated in the pixels of the image sensor, and the captured image is entirely white and hazy. Therefore, there is a problem that image quality is deteriorated.
[0006]
Furthermore, when the camera is mounted on a mobile phone or the like, the operator may accidentally drop the mobile phone or cause the camera to collide with another object, and the camera may be impacted. Therefore, it is necessary to take measures to allow the camera to perform a desired photographing operation even when the camera receives an external impact.
[0007]
The present invention has been made in view of the above circumstances, and an object of the present invention is to solve the troublesome operation of photographing with a camera, and when the state of waiting for photographing is long, not to mention when not photographing. In this way, it is possible to prevent the image sensor from being burned or damaged by strong light such as sunlight, or to prevent the color filter from fading. It is another object of the present invention to provide a portable information terminal device equipped with a camera capable of preventing a decrease in image quality or the like, and capable of reliably performing a photographing operation even when an external impact is applied due to a fall, a collision, or the like.
[0008]
[Means for Solving the Problems]
The portable information terminal device of the present invention is a portable information terminal device comprising: a main body having an imaging window; and a camera disposed inside the main body and configured to photograph a subject and including a lens and an imaging element. It is characterized by including a light-shielding vane that is disposed closer to the subject than the element and opens and closes an optical path leading to a photographing window, an electromagnetic actuator that drives the light-shielding blade, and a control unit that drives and controls the electromagnetic actuator.
According to this configuration, for example, the electromagnetic actuator closes the shooting window in the non-shooting mode, and opens and closes the shooting window in the shooting mode. Further, the light shielding blade can be used as a barrier in the non-photographing mode and as a mechanical shutter in the photographing mode. Accordingly, it is possible to prevent entry of a strong light beam during non-photographing, and to prevent damage due to burning of the image sensor or fading of a color filter in front of the image sensor.
[0009]
In the above configuration, it is possible to adopt a configuration in which the light shielding blade is disposed closer to the subject than the lens.
According to this configuration, the light-shielding blade can be used not only as a barrier or a mechanical shutter for protecting the image sensor, but also as a barrier for protecting the lens.
[0010]
In the above configuration, it is possible to adopt a configuration in which the light shielding blade is kept in a state in which the optical path leading to the imaging window is always closed in the non-imaging mode.
According to this configuration, in the non-photographing mode (non-photographing state), the light shielding blade is automatically kept in the closed state. In this case, it is possible to prevent the closing operation, which is a concern in the case, from being forgotten. That is, when the image is not taken, the light-blocking blades are kept in a state in which the imaging window is always closed, so that it is possible to prevent strong light or dust from entering from outside, and to protect the image sensor or the lens.
[0011]
In the above configuration, it is possible to adopt a configuration in which, when the control mode is changed from the non-photographing mode to the photographing mode, the electromagnetic actuator is energized so that the light-shielding blades perform the closing operation after performing the closing operation in advance. .
According to this configuration, in the non-shooting mode, if the light-shielding blade is opened due to an external impact or the like, the light-shielding blade is closed once at the time of shifting to the shooting mode (in a standby state for shooting). Then, the electric charges accumulated in the image sensor up to that time can be discharged, and thereafter, by opening the light shielding blades, the mode can be shifted to the composition determination mode before photographing. This makes it possible to prevent the captured image from becoming white and hazy, especially when the subject has high luminance, and to obtain a high-quality image.
[0012]
In the above configuration, it is possible to adopt a configuration in which, when a release operation is performed in the shooting mode, the electromagnetic actuator is energized after a predetermined time elapses to cause the light-shielding blade to perform a closing operation.
According to this configuration, after a lapse of a predetermined time (time required to reach an appropriate exposure amount) from the release operation, the light-blocking blade is driven and controlled to perform the closing operation. That is, the exposure time (exposure time) can be set with high accuracy by using the light-shielding blade as a mechanical shutter having a greater shielding effect than an electronic shutter performed by drive control of the image sensor. Thereby, a high-quality image can be obtained.
[0013]
In the above configuration, when the release operation is performed in the photographing mode, immediately before the imaging device starts photographing the subject, the control unit causes the light shielding blade to perform a closing operation once from the open state and then performs the opening operation again. For this purpose, a configuration in which the electromagnetic actuator is energized can be adopted.
According to this configuration, when capturing an image of a subject with the image sensor, by temporarily closing the open light shielding blade, it is possible to discharge the electric charge accumulated in the image sensor before that. That is, if the charge accumulation is performed on top of the charge accumulated before the start of photographing, the same phenomenon as the double exposure on the film is caused, and the image quality is deteriorated. Thus, a clear and high-quality image can be obtained.
[0014]
In the above configuration, it is possible to adopt a configuration in which the control unit automatically switches to the non-photographing mode when the release operation is not performed for a predetermined time in the photographing mode.
According to this configuration, when the release operation is not performed even after the lapse of the predetermined time, the mode is automatically switched to the non-photographing mode, and the light shielding blade performs the closing operation. Therefore, it is possible to prevent the shooting window from being left open. This can prevent entry of a strong light beam and the like, and can more reliably prevent damage due to burning of the image sensor or fading of a color filter in front of the image sensor.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
1 to 5 show one embodiment of a portable information terminal device (here, a portable telephone) according to the present invention. FIG. 1 is an external front view of the portable information terminal device, and FIG. 2 shows a light shielding blade and an electromagnetic actuator. FIG. 3 is a front view, FIG. 3 is a sectional view of a camera including light-shielding blades, FIG. 4 is a block diagram showing a control circuit of the entire system, and FIG. 5 is a flowchart showing a control sequence.
[0016]
As shown in FIGS. 1 to 4, the mobile phone has operation buttons 11 for performing various operations and a display unit (liquid crystal monitor) 12 for displaying various information arranged on the surface of a main body 10. An antenna 13 for transmitting and receiving signals is provided to be able to expand and contract, and an imaging window 14 is provided on the surface of the main body 10 and near the display unit 12.
A camera 20 is arranged inside the main body 10 behind the photographing window 14, and a circuit board on which various electronic components constituting a control circuit and the like are mounted is arranged in another internal area.
[0017]
As shown in FIGS. 1 to 3, the camera 20 is fixed to the inner wall of the main body 10, and includes a lens 21 (first lens 21 a and second lens 21 b), a CCD (charge coupled device) 22 as an image sensor, A light-blocking vane 23 disposed behind the imaging window 14 and on the subject side of the lens 21 (first lens 21a) (ie, on the subject side of the CCD 22), and a moving magnet type as an electromagnetic actuator for driving the light-shielding vane 23 to open and close. Motor 24 and the like.
[0018]
As shown in FIG. 2, the light-shielding blade 23 has a support hole 23 a through which the support shaft 25 passes, and an elongated hole 23 b to which a drive pin 24 a ′ described later is connected, and is rotatably supported by the support shaft 25. Thus, the imaging window 14 is reciprocated between a closed position for closing the imaging window 14 (a position indicated by a solid line) and an open position for opening (a position indicated by a two-dot chain line) to open and close the imaging window 14.
As described above, the light-shielding blade 23 is disposed closer to the subject than the CCD 22 and the lens 21 (the first lens 21a and the second lens 21b). A strong light beam (eg, sunlight) can be prevented from burning out the CCD 22 or fading the color filter provided on the front surface of the CCD 22, and preventing the lens 21 from being scratched or dusted. it can.
[0019]
As shown in FIG. 2, the motor 24 includes a rotor 24a having a drive pin 24a 'deviated from the center of rotation and rotating within a predetermined angle range, an exciting coil 24b, a yoke 24c forming a magnetic path, and the like. When the coil 24b is energized to open, the rotor 24a causes the light-shielding blades 23 to perform an opening operation, and when the coil 24b is energized to close, the rotor 24a causes the light-shielding blades 23 to perform a closing operation.
In the non-energized state, the rotor 24a is held at both ends of the rotation range by magnetic attraction, and holds the light shielding blade 23 in an open state or a closed state.
[0020]
As shown in FIG. 4, the control circuit includes a control unit 31 including a CPU or the like as control means for issuing various control signals and controlling overall control, a CCD drive circuit 32 for turning on / off power supply to the CCD 22, and the like. An image signal processing circuit 33 that processes an image signal captured by the CCD 22, an image display circuit 34 that performs processing for displaying a captured image on the display unit 12, a motor drive circuit 35 that controls energization of the motor 24, A storage unit 36 for storing the captured image information and the like, a main switch 37 for activating the camera 20, a release switch 38 for performing a release operation of the camera 20 at the time of shooting, and other processes for transmitting and receiving signals via the antenna 13. And a transmission / reception processing circuit (not shown) for performing the processing. The main switch 37 and the release switch 38 are incorporated as a part of the operation button 11 arranged on the surface of the main body 10.
[0021]
The control unit 31 performs arithmetic processing, determination processing, and the like based on various detection signals, operation command signals, and the like, and transmits various control signals.
For example, the control unit 31 determines the light amount level of the reflected light from the subject based on the image information obtained through the CCD 22 and the image signal processing circuit 33, and calculates the optimal exposure time for photographing.
Further, when the release switch 38 is turned on by the release operation of the operator, the control unit 31 issues a control signal to the motor drive circuit 35 so as to apply predetermined power to the motor 24, A control signal for image capturing (such as turning on / off an electronic shutter) is issued to the CCD drive circuit 32.
[0022]
Further, the control unit 31 sends a control signal for causing the light shielding blade 23 to perform an opening / closing operation so that the camera 20 is set to a shooting mode / non-shooting mode by an on / off operation of the main switch 37 by the operator. The control signal is sent to the CCD drive circuit 32, and the control signal for displaying the captured image on the display unit 12 is sent to the image display circuit.
[0023]
The main switch 37 is turned on to switch from a non-shooting mode (a state in which no shooting is performed) to a shooting mode (a shooting standby state) to activate the camera 20 and to perform a moving image shooting and a still image shooting standby state. When the camera is switched from the shooting mode to the non-shooting mode by an OFF operation to set a non-shooting state in which a moving image and a still image cannot be shot, the CCD 22 is controlled via the control unit 31 and the CCD driving circuit 32. And a trigger when turning on / off the power supply to the power supply.
[0024]
In addition, the main switch 37 is used to switch the non-photographing mode to the photographing mode, to cause the light shielding blade 23 to perform the closing operation and then to perform the opening operation, or to switch from the photographing mode to the non-photographing mode. In order to cause the light-shielding blades 23 to perform a closing operation, the control unit 31 and the motor drive circuit 35 serve as a trigger for controlling the energization of the motor 24.
As described above, when the mode is switched to the non-photographing mode, by closing the light shielding blade 23, the photographing window 14 is always closed in the non-photographing state in which the camera 20 is not used. Etc. can be prevented from entering. Thereby, it is possible to prevent the CCD 22 from being burned out and to prevent the lens 21 from being scratched or dust or the like.
[0025]
The release switch 38 serves as a trigger for photographing a still image of a subject in a photographing mode in which the main switch 37 is turned on (a stand-by state for photographing a still image). That is, when the release switch 38 is turned on by, for example, one push operation (release operation) of the operation button 11, the light-shielding blades 23 perform an opening operation after performing a closing operation once, and a predetermined time ( The control unit 31 issues a control signal to the motor drive circuit 35 so that the light-shielding blade 23 performs the closing operation after the elapse of the exposure time.
[0026]
When the release switch 38 is turned on, the CCD 22 is once turned off and turned on again following the closing operation of the light shielding blade 23 (that is, after the accumulated charge is discharged and initialized). The control unit 31 issues a control signal to the CCD drive circuit 32 so as to start accumulating and capture a still image (turn on (open) / off (close) the electronic shutter, etc.).
[0027]
As described above, by causing the light-shielding blade 23 to perform the closing operation once, it is ensured that the light-shielding blade 23 is in the initial position (closed position) even when the light-shielding blade 23 is opened by receiving an impact or the like despite the non-photographing mode. Position), and predetermined drive control based on this initial position can be performed. Further, by temporarily closing the light-shielding blades 23 before photographing, the discharge of the charges accumulated in the CCD 22 is reliably performed, and the phenomenon of white haze can be prevented particularly when the subject has high brightness, and a high-quality image is obtained. be able to.
[0028]
Next, the photographing operation of the mobile phone with the camera 20 will be described with reference to the flowchart of FIG.
First, when the main switch 37 is off, the camera 20 has not been activated and is in the non-photographing mode (step S1). At this time, the light shielding blade 23 is kept in a state where the imaging window 14 is closed. Therefore, the entry of light rays from the outside is prevented, and the CCD 22, the lens 21 and the like are protected.
[0029]
Here, when the main switch 37 is turned on (step S2), the camera 20 is activated and shifts to the shooting mode. The light-shielding blade 23 is driven to perform the closing operation regardless of the closed position or the open position. Therefore, the light-shielding blade 23 is held as it is in the closed state, and closed in the open state to close the imaging window 14 (step S3). Subsequently, control is performed so that the CCD 22 is turned off and the already accumulated charges are discharged (step S4).
[0030]
Subsequently, the light-shielding blades 23 perform an opening operation (step S5), so that a moving image can be captured by the CCD 22. Here, while looking at the display unit 12, a composition to be shot as a still image is set (step S6).
When the composition setting is completed and the operator performs the release operation and turns on the release switch 38 (step S7), first, the light amount level (brightness) of the subject is measured based on the image information of the CCD 22. Then, the exposure time (shutter second time) optimal for photographing is determined (step S8).
[0031]
Next, the light-shielding blade 23 performs a closing operation (step S9), and then the CCD 22 is turned off (the electronic shutter is closed) (step S10), and the charges accumulated up to that point are discharged (step S11). Here, by closing the light-shielding blade 23 having a large shielding effect, unnecessary charges accumulated before photographing can be reliably discharged even when the subject is particularly high in brightness. The phenomenon in which the photographed image corresponding to the above is blurred in white can be prevented.
[0032]
Subsequently, the light-shielding blades 23 perform an opening operation (step S12), the CCD 22 starts accumulating electric charges (the electronic shutter opens), and the exposure state is maintained for a predetermined exposure time (step S13). ). When it is determined that the appropriate exposure time has elapsed (step S14), the light shielding blade 23 performs a closing operation (step S15). Thus, the end of the exposure time is defined with high accuracy, so that a higher-quality image can be obtained as compared with the case where only an electronic shutter is used. Subsequently, the image data captured by the CCD 22 is transferred to be stored in the storage unit 36 (step S16). Then, it is determined whether or not the data transfer has been completed (step S17).
[0033]
When the data transfer is completed, it is determined whether or not the main switch 37 has been turned off (step S18). Here, when the main switch 37 is turned off, the camera 20 shifts to the non-photographing mode (step S19), and the light-shielding blade 23 performs a closing operation to close the photographing window 14. On the other hand, if the main switch 37 remains on, the process returns to step S5 and repeats the same sequence as described above.
[0034]
As described above, since the light-shielding blades 23 are automatically driven as a barrier for shielding the imaging window 14 and as a mechanical shutter at the time of imaging, it is possible to eliminate the troublesome operation at the time of imaging with the camera 20. During non-shooting, it is possible to prevent a strong light beam such as sunlight from entering, thereby preventing burning and breakage of the CCD 22 and fading of the color filter, etc., and also prevent scratches and dust from adhering to the lens 21. It is possible to obtain a high-quality image even when the subject has high brightness.
[0035]
FIG. 6 is a flowchart showing another control sequence of the camera 20 mounted on the portable information terminal device according to the present invention. In this embodiment, the same reference numerals (S1, S2,...) Denote the same control sequences as in the above-described embodiment, and a description thereof will be omitted.
[0036]
That is, in the control sequence according to this embodiment, as shown in FIG. 6, after opening the light shielding blade 23 (step S5), it is possible to set a composition to be photographed as a still image while looking at the display unit 12. At the stage (step S6), it is determined whether or not the release operation has been performed (step S7). If it is determined that the release operation has not been performed, the state of waiting for shooting is continuously set for a predetermined time. It is determined whether or not the time has elapsed (step S7 ').
[0037]
If it is determined that the predetermined time has not elapsed, the process returns to step S6, and the state in which the composition can be set is maintained. On the other hand, if it is determined that the predetermined time has elapsed, the process proceeds to step S19, and the control unit 31 shifts the camera 20 to the non-shooting mode assuming that the main switch 37 has been turned off. Then, the light shielding blade 23 performs a closing operation to close the imaging window 14.
[0038]
As described above, in the case where the shooting standby state continues for a long time, the operator forgets to turn off the main switch 37 and opens the shooting window 14 in order to automatically close the light shielding blade 23 and set the camera to the non-shooting mode. It can be prevented from being left as it is. Thus, the entry of a strong light beam can be prevented, and damage due to burning of the CCD 22 or fading of the color filter on the front surface of the CCD 22 can be more reliably prevented.
[0039]
In the above-described embodiment, the two lenses including the first lens 21a and the second lens 21b are described as the lenses 21 constituting the camera 20, but the present invention is not limited to this, and a single lens may be used. The configuration may be three or more.
Further, in the above-described embodiment, the configuration in which the light-blocking blades 23 are disposed closer to the subject than the lens 21 is shown. However, the present invention is not limited to this. It may be arranged. In this case, it is preferable to provide the imaging window 14 with a transparent plate that allows light to pass therethrough.
[0040]
In the above-described embodiment, the case of a single focus as the lens optical system of the camera 20 has been described. However, the present invention is not limited to this, and a camera having a zoom lens optical system capable of photographing from telephoto to wide angle is used. The light-shielding blade 23 according to the present invention may be employed. Further, in the above-described embodiment, the light-shielding blade that swings in a predetermined angle range has been described. However, the light-shielding blade is not limited to this. May reciprocate linearly, or a disk-shaped revolver may be rotated.
[0041]
In the above embodiment, the moving magnet type motor 24 having the rotor is shown as the electromagnetic actuator. However, the present invention is not limited to this, and other electromagnetic actuators including a stepping motor may be used.
Furthermore, in the above embodiment, a mobile phone is shown as the mobile information terminal device equipped with the camera 20, but other devices such as a mobile personal computer may be used.
[0042]
【The invention's effect】
As described above, according to the portable information terminal device of the present invention, the light-shielding vane that is disposed closer to the subject than the image sensor and opens and closes the optical path leading to the imaging window, the electromagnetic actuator that drives the light-shielding blade, and the electromagnetic actuator that drives the electromagnetic actuator By providing the control means for controlling, the trouble of manually opening and closing the photographing window can be eliminated, and the light shielding blade can be used as a barrier in the non-photographing mode and as a mechanical shutter in the photographing mode. As a result, it is possible to prevent the entry of a strong light beam during non-photographing, to prevent damage due to burnout of the image sensor, or to prevent fading of the color filter in front of the image sensor, etc. Can be prevented, and a high-quality image can be obtained.
In addition, by disposing the light-shielding blade on the subject side of the lens, the light-shielding blade can be used as a barrier for protecting the lens.
[Brief description of the drawings]
FIG. 1 is a plan view showing the appearance of a portable information terminal device (mobile phone) according to the present invention.
FIG. 2 is a front view showing a light shielding blade and an electromagnetic actuator.
FIG. 3 is a cross-sectional view showing a camera, a light shielding blade, an electromagnetic actuator, and the like incorporated in a main body.
FIG. 4 is a block diagram of the entire system including a camera control circuit.
FIG. 5 is a flowchart illustrating a control sequence when shooting with a camera.
FIG. 6 is a flowchart illustrating another control sequence when shooting with a camera.
[Explanation of symbols]
Reference Signs List 10 Main body 11 Operation buttons 12 Display unit 13 Antenna 14 Photographing window 20 Camera 21 (21a, 21b) Lens 22 CCD (imaging element)
23 Shading blade 24 Motor (electromagnetic actuator)
25 support shaft 31 control unit (control means)
32 CCD drive circuit 33 Image signal processing circuit 34 Image display circuit 35 Motor drive circuit 36 Storage unit 37 Main switch 38 Release switch

Claims (7)

A portable information terminal device comprising: a main body having an imaging window; and a camera including a lens and an imaging element arranged inside the main body for photographing a subject,
A light-shielding blade that is disposed closer to the subject than the image sensor and opens and closes an optical path leading to the imaging window, an electromagnetic actuator that drives the light-shielding blade, and a control unit that drives and controls the electromagnetic actuator,
A portable information terminal device characterized by the above-mentioned. The light-shielding blades are disposed closer to a subject than the lens,
The portable information terminal device according to claim 1, wherein: In the non-photographing mode, the light-shielding blade is kept in a state where an optical path leading to the photographing window is always closed.
The portable information terminal device according to claim 1 or 2, wherein: When the control unit is changed from the non-photographing mode to the photographing mode, the electromagnetic actuator is energized so as to perform the opening operation after the light shielding blade performs the closing operation in advance,
4. The portable information terminal device according to claim 3, wherein: The control means, when a release operation is performed in a shooting mode, after a lapse of a predetermined time, energizes the electromagnetic actuator to cause the light shielding blade to perform a closing operation,
The portable information terminal device according to claim 3 or 4, wherein: When the release operation is performed in the photographing mode, the control unit causes the light-shielding blade to perform a closing operation once from an open state and then perform an opening operation immediately before the photographing of the subject is started by the imaging element. To energize the electromagnetic actuator,
The portable information terminal device according to claim 5, wherein: In the photographing mode, when the release operation is not performed for a predetermined time in the photographing mode, the control unit automatically switches to the non-photographing mode.
The portable information terminal device according to any one of claims 3 to 6, wherein:

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