JP2005266647A - Image pickup device, lens movement control method, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image pickup device such as a digital camera which prevents the service life of a battery from being erroneously discriminated owing to the voltage drop at the time of zooming or auto-focusing of the image pickup device, and also to provide a lens movement control method and a program. <P>SOLUTION: A plurality of driving modes, to which voltage ranges 51 of the battery, speeds 52, and drop voltages 53 are made correspond, are preset, and a voltage of the battery is detected at the time of zooming (auto-focusing), and a drive control signal is sent to a driver for zoom (or a driver for auto-focus) so that a zoom lens (or a focus lens) is driven at a speed of a mode corresponding to a voltage range to which the detected voltage belongs, and thus a zoom motor A(or a focus motor) is driven to move the zoom lens (or the focus lens). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a lens movement control technique during zooming or autofocusing in an imaging apparatus such as a digital camera.

  Zooming, which changes the focal length, is commonly used in video cameras, as well as many silver halide cameras and digital cameras.

  An imaging device driven by a battery such as a digital camera has a problem that the apparent battery life is shortened due to the battery life judgment caused by temporarily consuming a large amount of current due to zoom operation, strobe light emission, etc. is there. On the other hand, a battery characteristic determination circuit (or voltage determination circuit) is provided in the digital camera, and battery characteristics (or voltage) are determined from voltage fluctuations that occur when various mechanisms are driven. There is one that selects either one of the power sequences (see, for example, Patent Document 1). According to the technology of Patent Document 1, for example, when changing the zoom magnification, in the normal sequence, the zoom motor and the AF motor are driven in parallel to change the zoom magnification and adjust the focus. In the power saving sequence, The AF (autofocus) motor and the zoom motor are driven at a voltage value lower than the drive voltage in the normal sequence. For this purpose, the zoom motor is first driven until a predetermined zoom magnification is reached, and after the zoom motor is stopped, the AF motor is driven to perform focus adjustment at the predetermined zoom magnification.

JP 2002-344794 A

  The zoom motor in zooming operates according to the drive waveform sent from the TG to the motor driver by sending a command for the CPU to move the zoom motor at a fixed speed upon detection of the zoom key operation. When driven, a current of several hundred mA (milliampere) flows, and a battery voltage drop occurs as shown in FIG. For this reason, the termination voltage of the battery needs to be a value that takes into account the width of this voltage drop.

  Further, when the driving speed of the zoom motor is increased, the current increases, and when the current increases, the voltage drop further increases. Accordingly, there is a problem that the apparent battery speed is shortened when the zoom motor driving speed is set to be high. In FIG. 2, (a) is an explanatory diagram of the transition of the battery voltage and the voltage drop due to the zoom drive. Reference numerals t1, t2, and t3 indicate the driving period of the zoom lens by the zoom operation, respectively, and reference numerals Vd1, Vd2, and Vd3 are the reference numerals. The width of voltage drop (drop voltage) in the drive periods t1, t2, and t3 is shown. Further, (b) is an enlarged view of the driving period of the zoom lens. Since the battery voltage falls with a curve as shown in FIG. 2A, the terminal voltage of the digital camera is set as a certain voltage VE on the curve. On the other hand, when the zoom operation is performed, even if the voltage drop widths Vd1 and Vd2 are subtracted in the driving periods t1 and t2, since the driving voltage> the terminal voltage VE as shown in the figure, the zoom driving is stably performed. When the voltage drop width Vd3 is subtracted at t3, the drive voltage <the termination voltage VE as shown in the figure, and the zoom operation becomes impossible.

  Here, according to the technique described in Patent Document 1, a predetermined drive sequence is selected and driven from a plurality of drive sequences according to the power supply capability of the power supply battery attached to the digital camera. Although the maximum power consumption can be reduced, in the power saving sequence described above, the zoom motor performs a zoom magnification change and a focus adjustment performed by driving the zoom motor and the AF motor in parallel in the normal sequence. After the zoom motor stops, the sequence is changed so that the AF motor is driven and focus adjustment is performed at a predetermined zoom magnification. Although it can be driven at a low voltage value, the maximum power consumption can be reduced, but the zoom motor and AF mode can be reduced. May occur during driving, there is a problem unable to prevent premature too battery life judgment is due to voltage drop.

  An object of the present invention is to provide an imaging apparatus, a lens movement control method, and a program that can prevent battery life from being judged too early due to a voltage drop during zooming or autofocus of an imaging apparatus such as a digital camera.

In order to solve the above-described problems, in the invention described in claim 1, in an imaging device that captures and records a subject, a zoom lens for performing photographing by changing a focal length, and a zoom lens based on control data are provided. Lens moving means for moving, zoom instruction means, voltage detection means for detecting the voltage of the power supply battery, zoom instruction detection means for detecting a zoom instruction by the zoom instruction means, and voltage detection means when a zoom instruction is detected The moving speed determining means for determining the moving speed of the zoom lens based on the voltage of the power battery detected by the control, and the control for generating the control data for moving the zoom lens at the determined moving speed and passing it to the lens moving means An image pickup apparatus comprising: a data generation unit;
As a result, the moving speed of the zoom lens is determined according to the voltage of the battery, so that if the battery voltage is low, the moving speed becomes slow and the drive current of the zoom motor becomes small. Therefore, since the battery drop voltage is also reduced, the battery termination voltage can be set lower.

According to the second aspect of the present invention, the movement is made up of a preset voltage range of the power battery, a moving speed of the zoom lens for each voltage range, and a drop voltage generated according to the moving speed of the zoom lens. The moving speed determining means has mode information, and the moving speed determining means corresponds to the voltage range to which the voltage of the power battery detected by the voltage detecting means belongs in the moving mode information, and the determined voltage range in the moving mode information. And a means for obtaining a differential voltage obtained by subtracting the voltage drop from the voltage of the power supply battery detected by the voltage detection means, and the movement speed associated with the voltage range to which the differential voltage belongs is included in the movement mode information. The imaging device according to claim 1, wherein the imaging device is determined as a moving speed.
Thus, zooming speed can be automatically determined according to the battery voltage classification and the drop voltage, so that if the battery voltage is low, the moving speed becomes slow and the driving current of the zoom motor becomes small. Accordingly, it is possible to prevent a decrease in battery life due to a voltage drop during zooming. In addition, since the zoom speed becomes slower as the electric capacity of the battery decreases, the user can know the remaining battery level sensuously.

According to a third aspect of the present invention, in an imaging apparatus that captures and records a subject, an autofocus lens for performing automatic focusing, a lens moving unit that moves the autofocus lens based on control data, Voltage detection means for detecting the voltage of the power battery, movement speed determination means for determining the movement speed of the autofocus lens based on the voltage of the power battery detected by the voltage detection means during autofocus, and the determined movement speed An image pickup apparatus comprising: control data generating means for generating control data for moving the autofocus lens and passing it to the lens moving means.
As a result, when the battery voltage drops, the drive speed of the focus lens becomes slow, so the drive current of the focus motor becomes small. Therefore, since the voltage drop of the battery is also reduced, the terminal voltage of the battery can be set to a lower place.

In the invention according to claim 4, the voltage range of the power supply battery, the moving speed of the autofocus lens associated with each voltage range, and the voltage drop generated according to the moving speed of the autofocus lens are preset. The moving speed determining means includes a means for determining a voltage range to which the voltage of the power battery detected by the voltage detecting means belongs, and a determination of the moving mode information. And a means for obtaining a differential voltage obtained by subtracting the voltage drop corresponding to the voltage range from the voltage of the power supply battery detected by the voltage detection means, and the movement associated with the voltage range to which the differential voltage belongs in the movement mode information. 4. The imaging apparatus according to claim 3, wherein the speed is determined as a moving speed of the autofocus lens.
Accordingly, the zoom speed according to the battery voltage classification and the drop voltage can be automatically determined and zoomed. Therefore, if the battery voltage is low, the moving speed becomes slow and the driving current of the autofocus motor becomes small. Accordingly, it is possible to prevent a decrease in battery life due to a voltage drop during zooming. Further, since the focusing time becomes longer as the electric capacity of the battery decreases, the user can know the remaining amount of the battery sensuously.

According to a fifth aspect of the present invention, there is provided a zoom lens for photographing at a different focal length, a zoom motor for moving the zoom lens, and a zoom motor driving means for driving the zoom motor, and photographing a subject. Lens movement control method in an image pickup apparatus for recording, wherein the voltage of a power supply battery is detected during a zoom operation, and the drive voltage of the zoom motor is changed based on the detected voltage I will provide a.
As a result, the zoom lens can be moved in accordance with the voltage of the battery. Therefore, if the battery voltage is low, the moving speed is slowed down and the drive current of the zoom motor is reduced.

According to a sixth aspect of the present invention, the zoom lens includes a zoom lens for shooting at a different focal length, and a lens moving unit that moves the zoom lens based on the control data. A lens movement control method in an imaging apparatus that generates and records in a storage memory, and the imaging apparatus has a plurality of movement modes that associate preset voltage ranges, speeds, and voltage drops of a power battery. The power supply battery voltage is detected during zoom operation, and control data for moving the zoom lens at a speed corresponding to the voltage range mode to which the detected voltage belongs is generated and sent to the lens moving means. A lens movement control method is provided.
Thereby, the moving speed of the zoom lens is determined according to the voltage of the battery, so that the same effects as those of the first and second aspects of the invention can be achieved.

According to a seventh aspect of the present invention, an autofocus lens for automatic focusing, a focus motor for moving the autofocus lens, and focus motor driving means for driving the focus motor are provided, and an object is photographed and A lens movement control method in an imaging apparatus that generates image data and records it in a storage memory, and detects the voltage of a power supply battery during autofocus and changes the drive voltage of the autofocus motor based on the detected voltage A lens movement control method is provided.
As a result, the focus lens can be moved in accordance with the voltage of the battery, so that if the battery voltage is low, the moving speed is slowed down and the drive current of the focus motor is reduced.

According to an eighth aspect of the present invention, an autofocus lens for automatic focusing and lens moving means for moving the autofocus lens based on control data are provided, and a subject is photographed to generate image data. A lens movement control method for an imaging apparatus that records in a storage memory, wherein the imaging apparatus has a plurality of movement modes that associate a voltage range, a speed, and a drop voltage of a power supply battery that are set in advance. The power supply battery voltage is detected at the time of focusing, and control data for moving the autofocus lens at a speed corresponding to the moving mode of the voltage range to which the detected voltage belongs is generated and sent to the lens moving means. A lens movement control method is provided.
Thus, since the moving speed of the focus lens is determined according to the voltage of the battery, the same effects as those of the third and fourth aspects of the invention can be achieved.

  According to a ninth aspect of the invention, there is provided the lens movement control method according to any one of the fifth to eighth aspects, wherein the imaging means is a digital camera.

  According to a tenth aspect of the present invention, there is provided the lens movement control method according to any one of the fifth to eighth aspects, wherein the imaging means is a mobile phone with a camera.

According to an eleventh aspect of the present invention, there is provided a zoom lens for taking a picture at a different focal length, a lens moving means for moving the zoom lens, and a zoom instruction means, and the subject is photographed and its image is taken. A program step that can be executed in the imaging apparatus that generates data and records the data in a storage memory, the program step for detecting a zoom instruction by the zoom instruction unit, and a voltage of the power supply battery when the zoom instruction is detected. A program step for determining the moving speed of the zoom lens based on the detected voltage, a program step for generating control data for moving the zoom lens at the determined moving speed, And a program step for outputting the control data to the lens moving means. To provide a program that butterflies.
Accordingly, when there is a zoom operation, the movement speed of the zoom lens is determined by following the battery voltage to generate control data, and the zoom lens can be moved at the determined movement speed. The same effect as that of the present invention can be obtained.

According to a twelfth aspect of the present invention, an autofocus lens for automatic focusing and lens moving means for moving the autofocus lens based on control data are provided, and a subject is photographed to generate image data. A program that can be executed by the imaging device that records in the storage memory, and that causes the voltage detection means to detect the voltage of the power supply battery during autofocus, and determines the moving speed of the autofocus lens based on the detected voltage A program step for generating control data for moving the autofocus lens at the determined moving speed, and a program step for outputting the generated control data to the lens moving means. A program is provided.
Thereby, at the time of auto-focusing, the movement speed of the focus lens can be determined by following the battery voltage to generate control data, and the focus lens can be moved at the determined movement speed. Has the same effect as.

  According to the present invention, since an abrupt voltage drop that occurs during zooming of the imaging apparatus can be alleviated, it is possible to prevent battery life from being judged too early due to a voltage drop that has occurred during zooming.

(Embodiment 1)
FIG. 1 is a block diagram showing an embodiment of a serial configuration of a digital camera. The digital camera 100 has a zoom function and an autofocus (AF) function, and has a lens block 1 for realizing the function.

  The lens block 1 includes a retractable lens group 11 including a zoom lens and a focus lens that are arranged so as to be movable in the optical axis direction, and position detection sensors 12 and 13 for the zoom position and the focus position in the lens group 11. A zoom motor 14 for moving the zoom lens, a focus motor 15 for moving the focus lens, an aperture actuator 16 for opening and closing an aperture (not shown), and a shutter actuator 17 for opening and closing a mechanical shutter are provided. Further, the motors and actuators 14 to 17 described above are driven by zoom (ZOOM), focus (Focus), aperture (Iris), and shutter (Shutter) drivers 21 to 24 provided in the driver block 2, respectively. Driven. That is, in the present embodiment, the zoom motor 14 and the zoom driver 21 and the focus motor 15 and the focus driver 22 correspond to the lens driving means of the present invention.

  Further, the digital camera 100 is a CCD image pickup device mainly composed of a CCD 31 which is an image pickup element arranged behind the photographing optical axis of the lens group 11, a CDS (Correlated Double Sampling) / AD block 32, and a TG (Timing Generator) 33. A system block 3 is provided. When the digital camera is set to the recording mode, the CCD 31 photoelectrically converts the optical image of the subject formed by the lens group 11 and scan-driven by the TG 33 to output a photoelectric conversion output for one screen at a certain period. To do. The CDS / AD block 32 performs noise removal and conversion to a digital signal by performing correlated double sampling on an analog output signal that has been gain-adjusted appropriately for each RGB color component after being output from the CCD 31, and a color process circuit. 4 is output.

  The color process circuit 4 performs color process processing for performing pixel interpolation processing on the input image pickup signal, generates a digital luminance signal (Y) and color difference signals (Cb, Cr), and is a control means of the present invention. To the CPU 5 that controls the entire digital camera 100. The CPU 5 is actually a microprocessor having an internal memory, various arithmetic processing circuits, a data input / output interface, and the like.

  The digital signal (image signal) sent to the CPU 5 is temporarily stored in the DRAM 6 and sent to the image display unit 7. The image display unit 7 includes a video encoder, a VRAM, a liquid crystal monitor, and a driving circuit thereof, generates a video signal based on the transmitted digital signal by the video encoder, and displays a display image based on the generated video signal, that is, a through image of the subject captured by the CCD 31. Is displayed on the liquid crystal monitor.

  The key input unit 8 includes various keys such as a power key, a recording / playback mode switching switch, a shutter key, a menu key, and a zoom key, and a sub CPU that receives the input and sends an operation signal corresponding to the input to the CPU 5. It is configured. The sub CPU sends a state signal indicating the state of the mode changeover switch, that is, the mode setting state to the CPU 5 as necessary. When the shutter key is operated in the recording mode described above, a trigger signal (operation signal) is output to the CPU 5.

  When the trigger signal is input, the CPU 5 reads out the image data for one screen captured from the CCD 31 at that time for each basic unit called a basic block of 8 pixels vertical by 8 pixels horizontal for each component of Y, Cb, and Cr. Write to the JPEG circuit 9. Further, the compressed data for one image compressed by DCT (discrete diffusion transform) encoding by the JPEG circuit 9 is read out and stored in the image recording unit 42. Specifically, the image recording unit 42 includes a card interface and various nonvolatile memory cards that are connected to the CPU 5 via the card interface and are detachably attached to the camera body.

  In the recording mode, the CPU 5 controls the lens control block 43 based on various programs stored in the rewritable non-volatile flash memory 41 and the operation signals described above from the key input unit 8. Drive signals to be sent to the various drivers 21 to 24 of the driver block 2 described above are generated, thereby controlling the position control of the zoom lens and the focus lens, the aperture opening degree, and the mechanical opening / closing operation. At this time, the lens position information detected by the position detection sensors 12 and 13 for the zoom position and the focus position is sequentially input to the CPU 5 via the lens control block 43. On the other hand, the image data recorded in the image recording unit 42 is read to the CPU 5 in the reproduction mode, decompressed by the JPEG circuit 9, sent to the image display unit 7, and displayed on the liquid crystal display monitor.

  For example, when the operation of the zoom key of the key input unit 8 is started, the CPU 5 drives the zoom lens according to the operation program stored in the flash memory 41 based on the voltage of the battery 46 detected by the voltage detection circuit 45. And a drive signal for driving the zoom motor 14 is sent to the zoom driver 21 of the driver block 2.

  The voltage detection circuit 45 detects the voltage of the battery 46 attached to the digital camera 100 and sends the detected value to the CPU 5. The battery 46 is a battery that can be attached to and detached from the digital camera 100, and supplies a driving current to the digital camera 100.

  FIG. 3 is a diagram showing an example of lens movement speed and motor drive current set for each mode. Modes 1 to 3 are associated with high speed, medium speed, and low speed, and current consumption and voltage drop in the mode are shown. It is shown.

  As described above, when the zoom motor is driven, a current of several hundred mA (milliampere) flows, and the voltage drop (drop voltage = Vd) of the battery 46 shown in FIG. 2 occurs. Further, when the drive speed of the zoom motor is increased, the current increases, and when the current increases, the voltage drop further increases.

  Therefore, a plurality of modes corresponding to the divided voltage range (FIG. 5) are set by dividing the voltage by a predetermined division value, and the CPU 5 uses the voltage of the battery 46 detected by the voltage detection circuit 45 as a basis. A mode is determined, and a drive control signal for the zoom motor 14 is sent to the zoom driver 21 so as to drive the zoom motor 14 at a speed corresponding to the mode. Note that the voltage drop shown in FIG. 3 means the maximum voltage drop in the corresponding mode. The voltage range in each mode is set to be larger than the corresponding maximum voltage drop.

  FIG. 4 is an explanatory diagram of a lens movement control method according to the present invention. Reference numerals T1, T2, T3, and T4 denote zoom drive periods (= zoom lens movement periods) by a zoom operation, and reference numerals VD1, VD2, VD3, VD4 indicates a drop voltage in the periods T1, T2, T3, and T4. Symbol VE means a terminal voltage in consideration of a voltage drop due to zoom driving, and symbol Vlim means a limit point of the battery operating voltage of the camera other than zoom driving.

  Since the voltage of the battery 46 decreases with a curve as shown in the figure, the CPU 5 selects the mode when the difference between the battery voltage detected by the voltage detection circuit 45 during zoom operation and the maximum voltage drop in mode 1 is larger than the lower limit voltage in mode 1. Drive control data for driving the zoom motor 14 at a driving speed of 1 is generated and sent to the zoom driver 21 of the driver block 2 to drive the zoom motor 14 so as to move the zoom lens at the mode 1 speed. If the difference between the battery voltage and the maximum voltage drop in mode 1 is smaller than the lower limit voltage in mode 1 and is within the voltage range of mode 2, drive control data for driving the zoom motor 15 at the drive speed of mode 2 is generated. The zoom motor 14 is driven so as to move the zoom lens at the speed of mode 2 by sending it to the zoom driver 21 of the driver block 2.

  Similarly, when the difference between the voltage of the battery 46 detected by the voltage detection circuit 45 during zoom operation and the maximum voltage drop in mode 2 is larger than the lower limit voltage in mode 2, the zoom motor 14 is driven at the mode 2 drive speed. Control data is generated and sent to the zoom driver 21 of the driver block 2 to drive the zoom motor 14 so as to move the zoom lens at the mode 2 speed. If the difference between the battery voltage and the detected battery 46 voltage and the maximum voltage drop in mode 2 is smaller than the lower limit voltage in mode 2 and is within the voltage range of mode 3, the zoom motor 14 is driven at the mode 3 drive speed. The drive control data to be generated is generated and sent to the zoom driver 21 of the driver block 2 to drive the zoom motor 14 so that the zoom lens is moved at the mode 3 speed.

  When the difference between the voltage of the battery 46 detected by the voltage detection circuit 45 during zoom operation and the maximum voltage drop in mode 3 is larger than the lower limit voltage (= terminal voltage VE) in mode 3, the zoom motor is driven at the mode 3 driving speed. A drive signal for driving 14 is generated and sent to the zoom driver 21 of the driver block 2 to drive the zoom motor 14 so as to move the zoom lens at the mode 3 speed. When the difference between the battery voltage and the voltage of the battery 46 detected in mode 3 and the maximum voltage drop in mode 3 is smaller than the lower limit voltage (= terminal voltage VE) in mode 3, the CPU 5 does not generate drive control data. That is, the digital camera 100 does not perform zooming.

  In the example shown in FIG. 4, since the difference between the battery voltage and the voltage drop in mode 1 is smaller than the lower limit voltage in mode 1 and larger than the lower limit voltage in mode 2 in period T1, CPU 5 generates drive control data for mode 2. In the zoom period T2, the difference between the battery voltage, the mode 2 and the drop voltage is smaller than the lower limit voltage of the mode 2 and larger than the lower limit voltage of the mode 3, so the drive control data for the mode 3 is generated. Further, since the difference between the battery voltage and the maximum voltage drop in mode 3 is not smaller than the lower limit voltage in mode 3 in period T3, CPU 5 generates drive control data for mode 3, but the battery voltage is in mode 3 in period T4. Since it is smaller than the lower limit voltage, the CPU 5 does not generate drive control data. However, since it is not smaller than the battery operating voltage limit point Vlim of the camera other than the zoom drive, the digital camera 100 can perform operations other than zooming.

  FIG. 5 is a diagram showing an embodiment of the drive mode table. The drive mode table 50 stores the voltage range obtained by dividing the voltage by a predetermined division value in association with the mode, and movement of the zoom lens. A speed field 52 that stores speed information, and a voltage drop field 53 that stores a maximum voltage drop when the zoom lens is moved at the speed. In the operation program, the drive mode table as shown in FIG. 5 may be set in the program as an internal constant table, or it is registered in the flash memory 41 as an external data table, and the operation program is executed at the time of execution. You may make it refer. The drive mode table corresponds to the movement mode information of the present invention.

  FIG. 6 is a flowchart showing the zoom lens drive control operation of the CPU according to the operation program. In FIG. 6, the CPU 5 checks the operation signal sent from the key input unit 8. If the zoom key is pressed, the process proceeds to step S2, and if not, the process proceeds to another process (step S1).

  When the zoom key is pressed, the CPU 5 causes the voltage detection circuit 45 to detect the voltage of the battery 46 (step S2), receives the voltage value detected from the voltage detection circuit 45, and the voltage range column of the drive mode table 50 The voltage range of 51 is searched, the voltage drop value is extracted from the voltage drop column 53 of the drive mode n (in the embodiment, n is any one of 1, 2, and 3) in which the acquired voltage falls within the voltage range, and the acquired voltage The voltage drop value is subtracted from the voltage range (step S3), the voltage value after the subtraction is compared with the voltage range in the voltage range column 51 of the drive mode table 50, and the voltage value after the subtraction is within the voltage range of the drive mode 1. It progresses to step S5, and when that is not right, it progresses to step S6 (step S4).

  If the voltage value after subtraction is within the voltage range of the drive mode 1, the CPU 5 zooms based on the moving speed (high speed) of the zoom lens in the speed column 52 corresponding to the voltage range of the drive mode 1 of the drive mode table 50. Drive control data (high-speed setting data) for the motor 14 is generated and sent to the zoom driver 21 of the driver block 2 (step S5).

  The voltage value after subtraction obtained in step S3 is compared with the voltage range in the voltage range column 51 of the drive mode table 50. If the voltage value after subtraction is within the voltage range of drive mode 2, the process proceeds to step S7. If not, the process proceeds to step S8 (step S6).

  When the voltage value after subtraction is within the voltage range of the drive mode 2, the CPU 5 is based on the moving speed (medium speed) of the zoom lens in the speed column 52 corresponding to the voltage range of the drive mode 2 of the drive mode table 50. Drive control data (medium speed setting data) for the zoom motor 14 is generated and sent to the zoom driver 21 of the driver block 2 (step S7).

  The voltage value after subtraction obtained in step S3 is compared with the voltage range in the voltage range column 51 of the drive mode table 50. If the voltage value after subtraction is within the voltage range of drive mode 3, the process proceeds to step S10 (step S10). S8) If not, zoom-inhibited display is performed (for example, the message “Cannot zoom due to insufficient battery capacity” is displayed on the image display unit 7), and the process proceeds to other processing (step S9).

  When the voltage value after subtraction is within the voltage range of the drive mode 3, the CPU 5 uses the zoom lens moving speed (low speed) in the speed column 52 corresponding to the voltage range of the drive mode 3 in the drive mode table 50. Then, drive control data (low speed setting data) of the zoom motor 14 is generated and sent to the zoom driver 21 of the driver block 2 (step S10).

  The zoom driver 21 drives the zoom motor 14 based on the received drive control data and moves the zoom lens (step S11).

  Further, the CPU 5 checks the operation signal sent from the key input unit 8, and when the zoom key is released, sends a motor drive stop signal to the zoom driver 21 to stop the zoom motor for other processing. If not, return to Step S2 (Step S12). If the digital camera 100 is configured to stop the zoom operation when the zoom key is pressed again, the CPU 5 checks the operation signal sent from the key input unit 8 and checks the zoom key. If is pressed, a motor drive stop signal is sent to the zoom driver 21 to stop the zoom motor and proceed to other processing. Otherwise, the process returns to step S2.

By the operation based on the flowchart of FIG. 6, when the battery voltage decreases, the zoom lens drive speed is reduced, and the drive current of the zoom motor is reduced. Therefore, since the voltage drop of the battery is also reduced, the terminal voltage of the battery can be set to a lower place. In addition, since the zoom speed becomes slower as the electric capacity of the battery decreases, the user can know the remaining battery level sensuously.
(Embodiment 2)
In the first embodiment, the zoom lens movement control method in the case of zooming has been described. However, when autofocus is selected in the digital camera 100 (FIG. 1), the CPU 5 detects the voltage of the battery 46 detected by the voltage detection circuit 45. The moving speed of the focus lens is determined according to the operation program stored in the flash memory 41 based on the above, and a drive signal for driving the focus motor 15 is sent to the focus driver 22 of the driver block 2. You can also. The drive mode table corresponds to the movement mode information of the present invention.

  FIG. 7 is a diagram showing an embodiment of the drive mode table. The drive mode table 70 stores a voltage range obtained by dividing the voltage by a predetermined division value in association with the mode, and movement of the focus lens. A speed field 72 that stores speed information, and a voltage drop field 73 that stores a maximum voltage drop when the zoom lens is moved at the speed. In the operation program, the drive mode table as shown in FIG. 7 may be set in the program as an internal constant table, or is registered in the flash memory 41 as an external data table, and the operation program is executed at the time of execution. You may make it refer.

  FIG. 8 is a flowchart showing the focus lens drive control operation of the CPU according to the operation program. In FIG. 8, the CPU 5 checks the operation signal sent from the key input unit 8 to check whether or not autofocus is selected. If autofocus is selected, the process proceeds to step T2, otherwise. Advances to other processing (step T1).

  When the auto focus is selected, the CPU 5 causes the voltage detection circuit 45 to detect the voltage of the battery 46 (step T2), receives the voltage value detected from the voltage detection circuit 45, and the voltage range of the drive mode table 70 The voltage range in the column 71 is searched, and the voltage drop value is extracted from the voltage drop column 73 of the drive mode n (in the embodiment, n is 1, 2, or 3) in which the acquired voltage corresponds to the voltage range, and acquired. When the voltage drop value is subtracted from the voltage (step T3), the voltage value after the subtraction is compared with the voltage range in the voltage range column 71 of the drive mode table 70, and the voltage value after the subtraction is within the voltage range of the drive mode 1 Proceeds to step T5, otherwise proceeds to step T6 (step T4).

  When the voltage value after the subtraction is within the voltage range of the drive mode 1, the CPU 5 automatically selects the autofocus based on the moving speed (high speed) of the focus lens in the speed column 72 corresponding to the voltage range of the drive mode 1 in the drive mode table 70. Drive control data (high-speed setting data) of the focus motor 15 is generated and sent to the focus driver 22 of the driver block 2 (step T5).

  The voltage value after subtraction obtained in step T3 is compared with the voltage range in the voltage range column 71 of the drive mode table 70. If the voltage value after subtraction is within the voltage range of drive mode 2, the process proceeds to step T7. If not, the process proceeds to step T8 (step T6).

  When the voltage value after subtraction is within the voltage range of the drive mode 2, the CPU 5 is based on the moving speed (medium speed) of the focus lens in the speed column 72 corresponding to the voltage range of the drive mode 2 of the drive mode table 70. Drive control data (medium speed setting data) of the focus motor 15 is generated and sent to the focus driver 22 of the driver block 2 (step T7).

  The voltage value after subtraction obtained in step T3 is compared with the voltage range in the voltage range column 71 of the drive mode table 70. If the voltage value after subtraction is within the voltage range of drive mode 3, the process proceeds to step T10 (step T8), otherwise, the autofocus disabled display is performed (for example, the message “Autofocus cannot be performed because the battery capacity is insufficient” is displayed on the image display unit 7), and the process proceeds to another process (step T9). .

  When the voltage value after subtraction is within the voltage range of the drive mode 3, the CPU 5 uses the focus lens moving speed (low speed) in the speed column 72 corresponding to the voltage range of the drive mode 3 in the drive mode table 70. Then, drive control data (low speed setting data) of the focus lens 15 is generated and sent to the focus driver 22 of the driver block 2 (step T10).

  The focus driver 22 drives the focus motor 15 based on the received drive control data to move the focus lens (step T11). Further, the CPU 5 checks the operation signal sent from the key input unit 8 and, when autofocusing is finished (= automatic focusing), sends a motor drive stop signal to the focus driver 22 to stop the focus motor. The process proceeds to another process, and if not, the process returns to step T2 (step T12).

  With the operation based on the flowchart of FIG. 8, when the battery voltage drops, the drive speed of the focus lens is slowed down, so the drive current of the focus motor is reduced. Therefore, since the voltage drop of the battery is also reduced, the terminal voltage of the battery can be set to a lower place. Moreover, since the focusing time becomes longer as the electric capacity of the battery decreases, the user can know the remaining amount of the battery sensuously.

  In the examples of the above-described embodiments, for the sake of explanation, there are three drive modes (mode 3, mode 2, and mode 3) (FIGS. 3 to 7). However, the drive modes are not limited to three types, and drive modes are not limited. May be two types or four or more types. That is, the drive mode table can be created by determining the voltage range in association with the lens movement speed classification at the time of design based on the use of the digital camera and the convenience in use, and measuring the drop voltage.

  In each of the above embodiments, the digital camera has been described as an example. However, the zooming and autofocus lens movement control method of the present invention can be applied to a camera-equipped mobile phone as it is.

  In each of the above embodiments, a digital camera has been described as an example of an imaging device, but the term imaging device is not limited to a digital camera. For example, an electronic camera or a video camera provided with a display unit, a mobile phone with a camera, a mobile information terminal with a camera, and the like are also included.

  As mentioned above, although one Example of this invention was described, this invention is not limited to the said Example, It cannot be overemphasized that various deformation | transformation implementation is possible.

It is a block diagram which shows one Example of the continuous structure of a digital camera. It is explanatory drawing which shows transition of the zoom drive voltage at the time of zooming. It is a figure which shows one Example of the drive speed and drive current which were set according to drive mode. It is explanatory drawing of the lens movement control method of this invention. It is a figure which shows one Example of a drive mode table. It is a flowchart which shows the zoom lens drive control operation | movement of CPU by an operation program. It is a figure which shows one Example of a drive mode table. It is a flowchart which shows the focus lens drive control operation of CPU by an operation program.

Explanation of symbols

5 CPU (zoom instruction detecting means, moving speed determining means, control data generating means)
8 Key input section (zoom instruction means)
14 Zoom motor (lens moving means)
15 Focus motor (lens moving means)
21 Zoom driver (lens moving means, zoom motor driving means)
22 Focus driver (lens moving means, focus motor driving means)
45 Voltage detection circuit (voltage detection means)
46 battery (power battery)
50 Drive mode table (movement mode information)
70 Drive mode table (movement mode information)
100 Digital camera (imaging device)

Claims (12)

In an imaging device that captures and records a subject,
A zoom lens for changing the focal length and shooting,
Lens moving means for moving the zoom lens based on the control data;
Zoom instruction means;
Voltage detection means for detecting the voltage of the power battery;
Zoom instruction detecting means for detecting a zoom instruction by the zoom instruction means;
A moving speed determining means for determining a moving speed of the zoom lens based on the voltage of the power supply battery detected by the voltage detecting means when a zoom instruction is detected;
Control data generating means for generating control data for moving the zoom lens at the determined moving speed and passing it to the lens moving means;
An imaging apparatus comprising: It has movement mode information consisting of a preset voltage range of the power battery, a moving speed of the zoom lens for each voltage range, and a drop voltage generated according to the moving speed of the zoom lens,
The moving speed determining means includes a means for determining a voltage range to which the voltage of the power battery detected by the voltage detecting means belongs in the movement mode information, and a drop corresponding to the determined voltage range in the moving mode information. Means for obtaining a differential voltage obtained by subtracting a voltage from the voltage of the power supply battery detected by the voltage detection means, and the movement speed associated with the voltage range to which the differential voltage belongs is included in the movement mode information. The imaging apparatus according to claim 1, wherein the imaging apparatus determines the moving speed of the lens. In an imaging device that captures and records a subject,
An autofocus lens for performing automatic focusing, a lens moving means for moving the autofocus lens based on control data, a voltage detection means for detecting the voltage of the power battery,
A moving speed determining means for determining a moving speed of the autofocus lens based on the voltage of the power supply battery detected by the voltage detecting means during the autofocus; and for moving the autofocus lens at the determined moving speed. Control data generating means for generating the control data and passing it to the lens moving means;
An imaging apparatus comprising: Preliminarily set the voltage range of the power battery, the moving speed of the autofocus lens associated with each voltage range, and the moving mode information consisting of a set of voltage drops generated according to the moving speed of the autofocus lens,
The moving speed determining means includes a means for determining a voltage range to which the voltage of the power battery detected by the voltage detecting means belongs in the movement mode information, and a drop corresponding to the determined voltage range in the moving mode information. Means for obtaining a differential voltage obtained by subtracting the voltage from the voltage of the power supply battery detected by the voltage detection means, and the movement speed associated with the voltage range to which the differential voltage belongs is included in the movement mode information. The imaging apparatus according to claim 3, wherein the imaging apparatus determines the moving speed of the focus lens. A lens movement control method in an imaging apparatus, which includes a zoom lens for shooting at a different focal length, a zoom motor that moves the zoom lens, and a zoom motor driving unit that drives the zoom motor, and that captures and records a subject Because
A lens movement control method comprising: detecting a voltage of a power source battery during a zoom operation; and changing a drive voltage of the zoom motor based on the detected voltage. An imaging device that includes a zoom lens for shooting at a different focal length and a lens moving unit that moves the zoom lens based on control data, shoots a subject, generates image data thereof, and records the image data in a storage memory A lens movement control method in an apparatus, comprising:
The imaging apparatus has a plurality of movement modes in which the preset voltage range, speed, and voltage drop of the power battery are associated with each other,
Detecting the voltage of the power battery during zoom operation, generating control data for moving the zoom lens at a speed corresponding to the mode of the voltage range to which the detected voltage belongs, and sending the control data to the lens moving means A lens movement control method. An autofocus lens for automatic focusing, a focus motor for moving the autofocus lens, and a focus motor driving means for driving the focus motor are provided, the subject is photographed, and image data thereof is generated and recorded in a storage memory. A lens movement control method in an imaging apparatus,
A lens movement control method comprising: detecting a voltage of a power supply battery during autofocusing; and changing a driving voltage of the autofocus motor based on the detected voltage. A lens in an imaging apparatus that includes an autofocus lens for automatic focusing and a lens moving unit that moves the autofocus lens based on control data, shoots a subject, generates image data thereof, and records the image data in a storage memory A movement control method comprising:
The imaging device has a plurality of movement modes in which a preset voltage range, speed, and voltage drop of the power battery are associated with each other,
The power supply battery voltage is detected at the time of automatic focusing, and control data for moving the autofocus lens at a speed corresponding to the moving mode of the voltage range to which the detected voltage belongs is generated to the lens moving means. The lens movement control method characterized by sending.   The lens movement control method according to claim 5, wherein the imaging unit is a digital camera.   9. The lens movement control method according to claim 5, wherein the image pickup unit is a camera-equipped mobile phone. An image pickup that includes a zoom lens for shooting at a different focal length, a lens moving unit that moves the zoom lens, and a zoom instruction unit, shoots a subject, generates image data thereof, and records the image data in a storage memory A program executable on the device,
A program step for detecting a zoom instruction by the zoom instruction means, a program step for causing the voltage detection means to detect a voltage of a power supply battery when a zoom instruction is detected, and a movement of the zoom lens based on the detected voltage A program step for determining the speed, a program step for generating control data for moving the zoom lens at the determined moving speed, and a program step for outputting the generated control data to the lens moving means;
A program characterized by comprising: Executed in an imaging apparatus that includes an autofocus lens for automatic focusing and a lens moving unit that moves the autofocus lens based on control data, and shoots a subject to generate image data and records the image data in a storage memory A possible program,
A program step for causing the voltage detection means to detect the voltage of the power supply battery during autofocus, a program step for determining the moving speed of the autofocus lens based on the detected voltage, and the autofocus lens at the determined moving speed A program step for generating control data for moving the lens, a program step for outputting the generated control data to the lens moving means,
A program characterized by comprising:

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