JP2004247969A - Imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging apparatus in which an initialization time is shortened when an imaging mode is set and the occurrence of out-of-focus is prevented by recuring the precision of focus. <P>SOLUTION: A decision is made whether a focal position detection signal is HIGH or not and the operation is repeated while moving a focal point optical system in the focus near direction if it is not HIGH otherwise the focal point optical system is moved in the focus inf direction. A decision is then made whether the focal position detection signal is LOW or not and the operation is repeated while moving the focal point optical system in the focus inf direction if it is not LOW otherwise a focus containing position is set at an imaging mode set position. Thereafter, a decision is then made whether a zoom position detection signal is LOW or not, and the operation is repeated while moving the focal point optical system in the zoom containing direction if it is not LOW otherwise the focal point optical system is set at a zoom containing position thus completing an imaging mode release operation. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an imaging apparatus, and more particularly, to a method of shortening a focus initialization operation of an imaging apparatus that performs an automatic focusing operation such as a digital camera.
[0002]
[Prior art]
2. Description of the Related Art An imaging apparatus such as a conventional digital camera that performs an automatic focusing operation performs an initialization operation of an optical system that performs focus adjustment when a shooting mode is set by turning on a power supply. In addition, when the photographing mode is set, it is necessary to initialize the variable power optical system, the shutter, and the aperture.
As a prior art relating to such initialization, Japanese Patent Application Laid-Open No. 2001-4896 discloses a technique for shortening the initialization time of a lens system immediately after power is turned on. According to this, in an imaging lens device including a lens driving mechanism for driving a variator and a focus lens of a photographing lens and a reset mechanism for initializing the lens driving mechanism, a reset mechanism for initializing the position of the variator lens driving mechanism is provided. It is arranged near the wide-angle end, and a reset mechanism for initializing the focus lens driving mechanism is arranged near an infinity in-focus position when the variator is at a position where the variator is initialized.
Japanese Patent Application Laid-Open No. 5-83613 discloses a technique for terminating the initialization processing of the focus lens while the screen is muted and shortening the time required to control the focus lens to the optimum position. According to this, in a video camera using an inner focus lens, a driving means for controlling the focus lens to a desired position, a focus lens support for winding and fixing the focus lens, and a position for initializing the focus lens And a detecting means for detecting that the focus lens has been set in the inner focus lens. Also, a plurality of initial positions of the focus lens are set.
[Patent Document 1] JP-A-2001-4896
[Patent Document 2] JP-A-5-83613
[0003]
[Problems to be solved by the invention]
However, when the processing of the conventional initialization operation is performed at the same time, the respective power consumptions are duplicated, and a large amount of current flows at the same time, so that there is a problem that the operation of the camera is stopped with the battery having the last life. Therefore, it is conceivable to perform each of the processes in a time-series manner. In this case, however, it takes a long time to be able to take a picture when the photographing mode is set, so that a shutter chance is missed. There was a problem of feeling stress. Also, if the display on the LCD or the like is performed before the initialization of the focus adjustment optical system and the variable power optical system is completed, the above-described problem of the current consumption and the image displayed on the LCD may occur during the initialization operation of the optical system. There is also a problem that it is unsightly.
Patent Document 1 discloses that a reset mechanism for initializing the position of a variator lens drive mechanism is disposed near the wide angle end, and a reset mechanism for initializing a focus lens drive mechanism is provided at infinity when the variator is at a position where the variator is initialized. By arranging the variator and the focus near the focusing position, the driving amount at the time of initialization of the variator and the focus is reduced, and the initialization time immediately after the power is turned on is shortened. However, a reset mechanism for initializing the lens driving mechanism and a reset mechanism for initializing the focus lens driving mechanism must be provided, and there is a problem that the cost increases.
Patent Document 2 shortens the time required for the initialization processing of the focus lens when the power is turned on by installing a plurality of detecting means for detecting the position of the focus lens and setting a plurality of initial positions of the focus lens. .
However, both Patent Literatures 1 and 2 attempt to shorten the initialization time by reducing the drive amount at the time of initialization of the focus lens, and the initialization operation itself of the focus lens must be performed.
The present invention has been made in view of the above-described problems, and in an image pickup apparatus that performs an automatic focusing operation (auto focus) such as a digital camera, a focus shift is generated by shortening an initialization time at the time of setting a shooting mode and securing focus accuracy. It is an object of the present invention to provide an image pickup apparatus that prevents the image pickup operation.
[0004]
[Means for Solving the Problems]
In order to solve this problem, the present invention provides a zoom optical system having a zoom function, a zoom optical system moving means for moving the zoom optical system, and a position of the zoom optical system. Position detecting means for detecting the focal length, a focusing optical system for adjusting the focus, a focusing optical system moving means for moving the focusing optical system, a focus position detecting means for detecting the position of the focusing optical system, In an imaging apparatus including a control unit for performing control for moving a magnification optical system and a focus optical system, in the end operation of the focus optical system when a shooting mode is released, the focus optical system is moved to a shooting mode set position. In this case, the initialization operation of the focusing optical system when the photographing mode is set is omitted.
In a conventional imaging apparatus having a variable power optical system, a zoom initializing operation, a focus initializing operation, and an aperture shutter initializing operation are performed when setting to a photographing mode, and a focus ending operation is performed when releasing from the photographing mode. Then, the zoom end operation is performed. At this time, since the focus is set to the original focus storage position at the time of the focus end operation, the focus initialization operation has to be performed without fail at the time of setting to the shooting mode. Therefore, in the present invention, when exiting from the shooting mode, the focus end operation and the zoom end operation are performed, but by setting the focus storage position to the shooting mode set position during the focus end operation, The focus initialization operation is omitted to reduce the time for the initialization operation.
According to this invention, since the initialization operation of the optical system for performing the focus adjustment is not performed when the shooting mode is set, the start-up time when the shooting mode is set can be shortened, and the focus adjustment is performed during the normal operation. Since the position of the optical system and the control signal can be synchronized, even if the position of the optical system that performs focus adjustment and the control signal are out of sync, the amount of the shift is fed back to provide an image without focus shift. Can be provided.
According to a second aspect of the present invention, a focusing optical system that performs focus adjustment, a focusing optical system moving unit that moves the focusing optical system, a focus position detecting unit that detects a position of the focusing optical system, and moves the focusing optical system. In the imaging apparatus provided with control means for performing the control for storing the focus optical system in the shooting mode setting position in the end operation of the focusing optical system when the shooting mode is released, the shooting mode is set. The initialization operation of the focusing optical system can be deleted.
The present invention relates to an imaging apparatus having no variable magnification optical system, and performs a focus end operation when releasing from a shooting mode, but sets a focus storage position to a shooting mode set position during a focus end operation. The focus initialization operation is omitted when the camera is set to the photographing mode, thereby shortening the time required for the initialization operation.
According to this invention, the same operation and effect as those of the first aspect can be obtained.
[0005]
A variable power optical system having a variable power function, variable power optical system moving means for moving the variable power optical system, variable power position detecting means for detecting the position of the variable power optical system, and a focal point An image sensor that performs adjustment; an image sensor moving unit that moves the image sensor; an image sensor position detector that detects the position of the image sensor; and control that moves the variable power optical system and the image sensor. In the image pickup apparatus provided with the control means, in the focus end operation by the image pickup device when the photographing mode is released, the image pickup device is stored in the photographing mode set position, so that the focus by the image pickup device when the photographing mode is set is set. Is omitted.
According to the present invention, in an imaging apparatus having a variable power optical system, focusing is performed by moving an imaging element while fixing a third lens unit. And the zoom end operation, but by setting the storage position of the image sensor to the shooting mode setting position during the focus end operation by the image sensor, the focus initialization operation by the image sensor when setting to the shooting mode is omitted. This is to reduce the time for the initialization operation.
According to this invention, the same operation and effect as those of the first aspect can be obtained.
According to a fourth aspect of the present invention, the imaging device performs focus adjustment, an imaging device moving unit that moves the imaging device, an imaging device position detection unit that detects a position of the imaging device, and control for moving the imaging device. In the imaging apparatus provided with a control unit for performing the operation, when the imaging mode is terminated when the imaging mode is released, the imaging element is stored in the imaging mode setting position to initialize the imaging element when the imaging mode is set. The operation can be deleted.
According to the present invention, in an image pickup apparatus having no variable magnification optical system, focusing is performed by moving an image pickup device while fixing a third lens unit. Performs the operation, but sets the storage position of the image sensor to the shooting mode set position during the focus end operation by the image sensor, thereby omitting the focus initialization operation by the image sensor when setting the camera to the shooting mode. It saves time.
According to this invention, the same operation and effect as those of the first aspect can be obtained.
A fifth aspect of the present invention is characterized in that a switching point of the position detection signal of the variable power position or the focal position is arranged at a position close to a direction in which the automatic focusing scan is started in the photographing area.
According to this invention, even when the position of the optical system for performing focus adjustment is out of synchronization with the control signal, the switching point of the position detection signal is arranged near the start position of the automatic focusing scan, so that the speed is faster. The amount of deviation can be fed back.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail using embodiments shown in the drawings. However, the components, types, combinations, shapes, relative arrangements, and the like described in this embodiment are not merely intended to limit the scope of the present invention but are merely illustrative examples unless otherwise specified. .
FIG. 1 is a block diagram illustrating an example of a digital camera according to the first embodiment of the present invention. This digital camera includes a photographing optical system 1 having first to third groups of lenses and an aperture / shutter unit 27, a shutter drive unit 7 for driving the aperture / shutter unit 27, an aperture drive unit 18, and a drive source thereof. A shutter motor 6, an aperture motor 7, a motor driver 12 for driving these motors, a zoom drive unit 14 for driving the first and second lens groups, a zoom motor 13 as a drive source, and a zoom position , A position detector 29 for detecting the first and second lens positions, a focus driver 16 for driving the third lens group, a focus motor 15 as a drive source, and a third group. A position detecting unit 28 for detecting a lens position of the camera, an infrared cut OLPF 2 for cutting infrared light from light passing through the photographing optical system 1, and a CCD or the like. Image sensor 4 that photoelectrically converts the image data, an image sensor driver 26 that drives the image sensor 4, an F / E circuit 5 that incorporates a CDS, AGC, and A / D circuit, and compresses and decompresses the photoelectrically converted image data. An image processing unit 8 for performing image processing, a video amplifier 24 for amplifying an image signal for outputting an image to an external TV or the like, an external television 25, an LCD 23 for displaying a captured image, and storing signal data. A memory 10, a storage medium 11 for storing compressed image data, a main switch 19 for turning on / off the main body, a release switch 20 for photographing a subject, a zoom selection switch 21 for selecting a zoom, various modes And a control section / calculation section 9 which controls all controls.
[0007]
Next, a series of operations of the digital camera of the present embodiment will be described. When the main switch 19 is turned on, a signal from the main switch 19 is sent to the controller / arithmetic unit 9 and various initializations and the like are performed. Mode contents selected by the mode selection switch 22 such as a photographing mode, a reproduction mode, and an erasing mode are sent to the control unit / calculation unit 9 as signals, and each mode is set.
The operation when the shooting mode is selected will be described. In the case of the photographing mode, zoom operation is enabled, and the zoom position selected by the zoom selection switch 21 is sent to the control unit / calculation unit 9 as a zoom position signal. By transmitting a predetermined amount of signal from the control / calculation unit 9 to the motor driver 12 to move the lens to the selected zoom position, the focus motor 15 for focus drive and the zoom motor 13 for zoom drive are rotated. It becomes possible. The focus motor 15 and the zoom motor 13 are linked with the focus drive unit 16 and the zoom drive unit 14, respectively. The zoom drive unit has a count detection unit 30 for counting the rotation from the zoom motor. The zoom is linked with the variable power lens group in the photographing optical system 1, and the focus is linked with the focus lens in the photographing optical system 1, and is moved to a predetermined position and set to the selected zoom position. The zoom and the focus have position detection units 28 and 29, respectively, and the zoom performs position control based on the absolute position detected by the position detection unit 29 and the count by the count detection unit 30. Focus control is performed by an absolute position detected by the position detection unit 28 and a count by a pulse count. The aperture / shutter unit 27 is disposed in the photographing optical system 1, the aperture switches the aperture diameter according to the brightness, and the shutter performs an operation of blocking or passing the light amount to the image sensor.
[0008]
Next, an operation until the release switch 20 is pressed and an image is written on the recording medium will be described. When the release switch 20 is pressed, a signal from the release switch 20 is sent to the controller / arithmetic unit 9. On the other hand, the light that has passed through the photographing optical system 1 is cut by an infrared cut filter and an OLPF (optical low-pass filter) 2 to cut infrared light, thereby cutting off high-frequency components that are sources of false colors and moiré. Reach 4 The image sensor 4 is periodically driven by an image sensor driver 26. The light arriving at the image sensor 4 is converted into an electric signal by the image sensor 4. The converted electric signals are sent to CDS, AGC, and A / D 5, respectively. In the CDS, low-frequency noise is removed, and in the AGC, only the video signal is amplified to a specified level, then A / D-converted by an A / D and output as a digital signal. The output digital signal is sent to the image processing unit 8. The controller / arithmetic unit 9 which has received the signal from the release switch 20 controls the motor driver 12 to drive the focus motor 15 in order to perform a focusing operation (hereinafter referred to as AF) of the TTL contrast peak detection method. Output a signal. In response to the control signal, the focus lens moves for the AF operation via the focus drive unit.
The image processing unit 8 generates an AF evaluation value from a digital signal from the image sensor 4. The generated AF evaluation value is sent to the control unit / arithmetic unit, and a focus position is derived by arithmetic processing. Further, a signal for moving the focus lens to the focus position derived from the control unit / calculation unit is output, and the focus lens is moved to the focus position.
After the focus lens moves to the in-focus position, the respective digital signals output from the CDS, AGC, and A / D are sent to the image processing unit 8, where color information interpolation processing, white balance gain processing, and edge enhancement processing are performed. , .Gamma. Processing, conversion processing for separating a luminance signal and two color difference signals, and the like. In order to record the signal data in the recording medium 11, the signal data stored in the memory 10 is sent to the image processing unit 8 again, subjected to the synthesis and compression processing, and then written in the recording medium 11.
When displaying a through image for determining the composition, only the signal from the image sensor 4 which has been subjected to the thinning is output, and after passing through the CDS, AGC, and A / D 5, the image processing unit 8 performs the same operation. Is performed, and further thinning processing is performed. Thereafter, the image data is temporarily stored in the memory 10, sent to the image processing unit 8, subjected to video conversion processing, and output to the video amplifier 24. When a TV (television monitor) 25 is connected, a through image can be output to the TV monitor. Similarly, in order to display on the LCD (liquid crystal monitor) 23, conversion processing for display on the liquid crystal monitor is performed instead of the video conversion processing performed by the image processing unit 8, and output is displayed on the LCD (liquid crystal monitor) 23.
[0009]
FIG. 2 is a diagram showing the movement of the photographing lens and the output of a zoom position detection signal. The movement of the photographing lens, the zoom position detection signal, and the focus position detection signal will be described with reference to FIG. The photographing lens includes one group, two groups, and three groups. The first and second units are mechanically linked, and perform a zooming operation by rotation from a zoom motor. The third group is independently linked to the focus motor to perform focus adjustment. The zoom position detection signal is switched to a position P just before the storage position. With the switching point P as count 0, the WIDE position is at the 1750 count position and the TELE is at the 4000 count position. The storage position is at the -150 count position. Therefore, the zoom position can be set to a desired position by the zoom position detection signal and the zoom count. In FIG. 2, the position of the third group (focus) lens is indicated by an inf position. Although it is difficult to understand in FIG. 2, the positions of the third group fluctuate slightly.
FIG. 3 is a diagram showing a focus position at a typical zoom position and an output of a focus position detection signal. Assuming that the switching point P of the focus position detection signal is 0 pulse, the WIDE inf position is -16 pulses, the MEAN inf position is -32 pulses, the TELE inf position is -13 pulses, and the storage position is -38 pulses. It becomes. The extension to the near distance is on the object side (pulse increasing direction). Also, in this example, the shortest shooting distance is variable while the focus extension amount from WIDE to TELE is fixed. The feed amount for the same distance is small in WIDE, and increases as the position is closer to the TELE side. That is, when the shortest photographing distance is fixed, the feeding of WIDE is small, and the feeding amount of TELE is large. Incidentally, the storage positions of the zoom and the focus can be arbitrarily set.
[0010]
FIG. 4 is a flowchart for explaining a conventional setting operation to a shooting mode for comparison with the present invention. First, when a set signal to the photographing mode is detected (S1), it is checked whether the zoom position detection signal is LOW (S2). If the signal is not LOW, it is moved in the zoom housing direction (S12), and if LOW, the zoom wide position is repeated. (S3) It is checked whether the focus position detection signal is HIGH (S4). If it is not HIGH, it moves in the focus near direction (S13), and if it is HIGH, it moves in the focus inf direction (S5). It is checked whether the focus position detection signal is LOW (S6). If the focus position detection signal is not LOW, the focus position is moved in the direction of focus inf (S14). The shutter is set to the open position (S9), an image is displayed on the LCD (S10), and the photographing mode is set. That (S11).
FIG. 5 is a flowchart for explaining a conventional release operation to the shooting mode for comparison with the present invention. First, when a release signal from the photographing mode is detected (S21), the image display on the LCD is turned off (S22), and the shutter is set to the fully open position (S23). Next, it is checked whether the focus position detection signal is HIGH (S24). If the focus position detection signal is HIGH, the focus position is moved in the focus near direction (S31). If the focus position detection signal is HIGH, the focus position is moved in the focus inf direction (S25). If it is LOW, it is checked (S26). If it is not LOW, it moves in the focus inf direction (S32), and if it is LOW, it is set to the focus storage position (S27), and it is checked whether it is the zoom position detection signal LOW (S28). If it is not LOW, it moves in the zoom housing direction (S33), and if it is LOW, it is set to the zoom housing position (S29), and the shooting mode release operation is completed (S30).
As shown in FIG. 6, the focus storage position is set to the -16 pulse position which is the WIDE inf position. By doing so, the focus position when the shooting mode is set and the focus position when the shooting mode is released become the same, and if the focus initialization operation is performed when the shooting mode is released, the focus initialization operation when the shooting mode is set can be deleted. .
[0011]
FIG. 7 is a flowchart showing the operation at the time of setting the shooting mode when the shooting mode of the present invention is selected. The same operation has the same step number. First, when a set signal to the photographing mode is detected (S1), it is checked whether the zoom position detection signal is LOW (S2). If the signal is not LOW, it is moved in the zoom housing direction (S12), and if LOW, the zoom wide position is repeated. (S3), the aperture is set to the fully open position (S8), the shutter is set to the open position (S9), an image is displayed on the LCD (S10), and the setting to the photographing mode is completed (S11). As is clear from this flowchart, it is understood that steps S4 to S7 of the conventional steps in FIG. 4 are omitted, the "focus initialization operation" becomes unnecessary, and the time for setting the shooting mode is shortened.
FIG. 8 is a flowchart illustrating an operation of releasing the camera to the shooting mode. The same operation has the same step number. First, when a release signal from the photographing mode is detected (S21), the image display on the LCD is turned off (S22), and the shutter is set to the fully open position (S23). Next, it is checked whether the focus position detection signal is HIGH (S24). If the focus position detection signal is HIGH, the focus position is moved in the focus near direction (S31). If the focus position detection signal is HIGH, the focus position is moved in the focus inf direction (S25). It is checked whether it is LOW (S26). If it is not LOW, it is moved in the focus inf direction (S32), and if it is LOW, the focus storage position is set to the photographing mode set position (S34: this flow is different from FIG. 5). It is checked whether the zoom position detection signal is LOW (S28). If it is not LOW, it is moved in the zoom housing direction (S33), and if it is LOW, it is set to the zoom housing position (S29), and the shooting mode release operation is performed. Complete (S30).
Also, as the mechanism of the focus drive unit, a mechanism that does not cause a focus position shift due to vibration etc. is naturally adopted, but if an unexpected focus position shift occurs, the shift amount is not corrected, Unfocused shooting must be performed until the shooting mode is released. FIG. 9 shows an operation diagram when the present invention is performed during the AF operation at the zoom position WIDE. First, the reset operation will be described with reference to the digital camera described above. The absolute position of a focus member (lens, image sensor), a control performed by a position detection signal output from a position detection unit and a pulse signal of a focus motor are controlled. The purpose is to match the synchronization of the signals.
[0012]
In FIG. 9, the -16 pulse is the inf position and the 22 pulse is the near position. It is also assumed that the position of +2 pulse is the focus position. In this description, the hill-climbing AF is performed in all areas of the normal shooting area (from inf to near). The upper part performs an AF scan from the inf side to the near side, and the lower part performs an AF scan from the near side to the inf side. The movement of the focus member is indicated by an arrow, and AF scanning is performed in the range of (inf) margin (1) + normal photographing area (2) + near margin (3). As a result, it is determined that the in-focus position exists in the +2 pulse, and the camera moves to the +2 pulse position (4). Thereafter, backlash is removed, and the camera stops at the position of +2 pulse which is the focus position (5). Switching of the position detection signal is performed during the scan of the normal imaging region (2), and the synchronization of the control signal and the absolute position of the focus member (lens, imaging element) are matched at the switching point.
If the focus member is displaced, if the displacement is larger than the margin on the inf side and near side, the AF scan range to be executed will be displaced. And near-end defocusing occurs. In addition, when there is another distance measuring device, the focus position is moved based on the result of the distance measuring device, so that a focus shift occurs in any area. Similarly, in the distant view photographing mode or the like, a focus shift occurs in any area. If the switching of the position detection signal is detected during the operation of the focus member and the feedback is performed in this way, such a focus shift can be avoided.
FIG. 10 is a block diagram illustrating an example of a digital camera according to the second embodiment of the present invention. The same components are denoted by the same reference numerals, and duplicate description will be omitted. FIG. 10 differs from FIG. 1 in that three groups of lenses are omitted and the zooming function is eliminated. Therefore, the zoom motor 13, the zoom drive unit 14, the position detection unit 29, and the count detection unit 30 are also omitted.
FIG. 11 is a block diagram illustrating an example of a digital camera according to the third embodiment of the present invention. The same components are denoted by the same reference numerals, and duplicate description will be omitted. FIG. 11 differs from FIG. 1 in that the third lens unit is fixed and focus driving is performed by moving the image sensor 4.
[0013]
FIG. 12 is a block diagram illustrating an example of a digital camera according to the fourth embodiment of the present invention. The same components are denoted by the same reference numerals, and duplicate description will be omitted. FIG. 12 differs from FIG. 11 in that three groups of lenses are omitted and the zoom function is eliminated. Therefore, the zoom motor 13, the zoom drive unit 14, the position detection unit 29, and the count detection unit 30 are also omitted.
FIG. 13 is a diagram illustrating a case where the area in which the hill-climbing AF is performed is not the entire normal shooting area (from inf to near). That is, when the focus position is detected by the hill-climbing AF, the focus member is moved to the focus position without performing the subsequent AF scan. The upper part performs an AF scan from the inf side to the near side, and the lower part performs an AF scan from the near side to the inf side. In this case, when the switching point of the position detection signal is located at a position closer to the direction in which the AF scan is started in the normal shooting area, the switching point is more likely to be passed, and feedback can be performed more reliably. Become. Further, in the present embodiment, the synchronization of the control signal with the absolute position of the focus member (lens, imaging element) is matched during the AF operation, but may be matched during driving other than the AF operation.
FIG. 14 is a flowchart for explaining a conventional AF operation for comparison with the present invention. First, a release switch signal is detected (S41), and the current focus position is confirmed (S42). Next, the focus member is moved to the AF scan start position (S43). Then, an AF scan is performed (S44), the in-focus position is confirmed (S45), and if there is no in-focus position, the focus position is moved to a predetermined focus position (S48), and the absence of the AF in-focus position is displayed (S49). If there is an in-focus position in step S45, it is moved to the in-focus position (S46), and it is confirmed whether or not backlash removal is necessary (S47). If necessary, backlash removal is performed and return (S50). If it is not necessary, AF focusing display is performed (S51).
[0014]
FIG. 15 is a flowchart illustrating the AF operation of the present invention. The same operation has the same step number. First, a release switch signal is detected (S41), and the current focus position is confirmed (S42). Next, the focus member is moved to the AF scan start position (S43). Then, an AF scan is performed (S44), and it is checked whether or not the position detection signal is switched (S52). If there is a switch, it is checked whether or not it is switched at the stored pulse position (S56). For example, the shift amount between the stored pulse position and the switching pulse position is stored (S57), and the process proceeds to step S53. If the switching is performed in step S56, the process proceeds to step S53. If the position detection signal is switched in step S52, the AF scan is continued (S53), the AF scan is completed (S54), and the pulse shift amount is corrected. (S55), the in-focus position is confirmed (S45), and if there is no in-focus position, the focus position is moved to a predetermined focus position (S48), and no AF in-focus position is displayed (S49). If there is an in-focus position in step S45, it is moved to the in-focus position (S46), and it is confirmed whether or not backlash removal is necessary (S47). If necessary, backlash removal is performed and return (S50). If it is not necessary, AF focusing display is performed (S51).
In FIG. 15, the synchronization at the time of the AF operation may be performed only for the first AF operation after the shooting mode is set, or may be performed a plurality of times until the shooting mode is released.
[0015]
【The invention's effect】
As described above, according to the first to fourth aspects of the present invention, the initialization operation of the optical system for performing the focus adjustment is not performed when the shooting mode is set, so that the start-up time when the shooting mode is set can be shortened, and During normal operation, the position of the optical system that performs focus adjustment and the control signal can be synchronized, so even if the position of the optical system that performs focus adjustment and the control signal are out of sync, the amount of deviation is fed back. By doing so, it is possible to provide an image without defocus.
According to the fifth aspect, even when the position of the optical system for performing focus adjustment is out of synchronization with the control signal, the switching point of the position detection signal is arranged near the start position of the automatic focusing scan, so that the speed is faster. The amount of deviation can be fed back.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating an example of a digital camera according to a first embodiment of the present invention.
FIG. 2 is a diagram illustrating the movement of a photographing lens and output of a zoom position detection signal according to the present invention.
FIG. 3 is a diagram illustrating a focus position at a typical zoom position and an output of a focus position detection signal.
FIG. 4 is a flowchart illustrating a conventional setting operation to a shooting mode for comparison with the present invention.
FIG. 5 is a flowchart illustrating a conventional release operation to a shooting mode for comparison with the present invention.
FIG. 6 is a diagram illustrating a focus position at a zoom position according to the present invention and an output of a focus position detection signal.
FIG. 7 is a flowchart illustrating an operation when a shooting mode is set when the shooting mode of the present invention is selected.
FIG. 8 is a flowchart illustrating an operation of canceling a shooting mode according to the present invention.
FIG. 9 is a diagram illustrating an operation performed when an AF operation is performed at the zoom position WIDE of the present invention.
FIG. 10 is a block diagram illustrating an example of a digital camera according to a second embodiment of the present invention.
FIG. 11 is a block diagram illustrating an example of a digital camera according to a third embodiment of the present invention.
FIG. 12 is a block diagram illustrating an example of a digital camera according to a fourth embodiment of the present invention.
FIG. 13 is a diagram showing a case where the area where the hill-climbing AF of the present invention is performed is not the entire normal photographing area (from inf to near).
FIG. 14 is a flowchart illustrating a conventional AF operation for comparison with the present invention.
FIG. 15 is a flowchart illustrating an AF operation according to the present invention.
[Explanation of symbols]
Reference Signs List 1 shooting optical system, 6 shutter motor, 7 shutter drive unit, 9 control unit / calculation unit 12 motor driver, 13 zoom motor, 14 zoom drive unit, 15 focus motor, 16 focus drive unit, 17 aperture motor, 18 aperture drive unit , 27 aperture / shutter unit, 28, 29 position detector, 30 count detector

Claims (5)

Variable power optical system having a variable power function, variable power optical system moving means for moving the variable power optical system, variable power position detecting means for detecting the position of the variable power optical system, and focus optics for performing focus adjustment System, focus optical system moving means for moving the focus optical system, focus position detecting means for detecting the position of the focus optical system, and control for performing control for moving the variable power optical system and the focus optical system. Means, the imaging device comprising:
In the end operation of the focusing optical system when the shooting mode is released, the focusing optical system is stored in the shooting mode set position, thereby omitting the initialization operation of the focusing optical system when the shooting mode is set. Imaging device. A focusing optical system for performing focus adjustment, a focusing optical system moving unit for moving the focusing optical system, a focus position detecting unit for detecting a position of the focusing optical system, and a control for moving the focusing optical system. In an imaging device including a control unit,
In the end operation of the focusing optical system when the shooting mode is released, the focusing optical system is stored in the shooting mode set position, thereby omitting the initialization operation of the focusing optical system when the shooting mode is set. Imaging device. A variable power optical system having a variable power function, variable power optical system moving means for moving the variable power optical system, variable power position detecting means for detecting the position of the variable power optical system, and an image sensor for performing focus adjustment And an image sensor moving means for moving the image sensor, an image sensor position detecting means for detecting a position of the image sensor, and a control means for performing control for moving the variable magnification optical system and the image sensor. In the imaging device,
In the focus end operation by the image sensor when the shooting mode is canceled, the image sensor is stored in the shooting mode set position, thereby omitting the focus initialization operation by the image sensor when the shooting mode is set. An imaging device characterized by the following. An image sensor for performing focus adjustment, an image sensor moving means for moving the image sensor, an image sensor position detecting means for detecting a position of the image sensor, and a control means for performing control for moving the image sensor Imaging device,
In the focus end operation by the image sensor when the shooting mode is canceled, the image sensor is stored in the shooting mode set position, thereby omitting the focus initialization operation by the image sensor when the shooting mode is set. An imaging device characterized by the following. The switching point of the position detection signal of the variable power position or the focal position is arranged at a position close to the direction in which the automatic focusing scan is started in the photographing area. An imaging device according to claim 1.

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