JP5610926B2 - Imaging apparatus and control method thereof - Google Patents

Description

  The present invention relates to an imaging apparatus such as a digital camera or a digital video camera, and more particularly to an imaging apparatus capable of both capturing a visible light image and capturing an infrared light image.

  In general, a digital camera or a digital video camera includes a filter that removes an infrared light component from a light component incident on an image sensor from an imaging optical system. This is because the image sensor is also sensitive to infrared light components, so that the color reproducibility of the captured image is reduced due to the mixture of infrared light components, and the resolution is prevented from being lowered due to aberrations. Because.

  On the other hand, in order to enable photographing in a dark place where the amount of visible light is insufficient, an imaging apparatus provided with a filter switching means that puts and removes an infrared light removal filter on the optical path of the imaging optical system has been proposed. Yes. In normal visible light shooting (hereinafter referred to as visible light shooting mode), an infrared light removal filter is placed in the optical path for shooting, while the sensitivity of the image sensor is improved in dark places where there is little visible light. Therefore, the infrared light removal filter is moved out of the optical path to enable photographing with infrared light (hereinafter referred to as infrared light photographing mode) (see Patent Document 1).

  By the way, when the infrared light removal filter is taken in and out of the optical path in this way, the focus state of the imaging optical system changes depending on the presence or absence of the infrared light removal filter. For this reason, even when the subject is in focus in the visible light photographing mode, if the infrared light photographing mode is switched to the infrared light photographing mode, the subject is out of focus as a result of moving out of the optical path.

  FIG. 5 shows the correction amount of the focus lens position and the zoom lens position when the infrared light removal filter is moved from the optical path to the outside of the optical path in the imaging lens having a zoom lens that changes the magnification of the imaging optical system. It is the figure which showed the relationship. A curve indicated by L1 in FIG. 5 is a correction amount of the focus lens position under an environment of only visible light, and the left end in FIG. 5 indicates the wide-angle end position of the zoom lens, and the right end indicates the end position on the telephoto side. Yes. On the other hand, the curve indicated by L2 in FIG. 5 is the correction amount of the focus lens position under the environment of only infrared light, and is greatly different from the curve L1. In an environment where the components of visible light and infrared light are mixed, the correction amount has an intermediate characteristic between L1 and L2. The change in the correction amount according to the component ratio of visible light and infrared light in this way is due to the characteristics of chromatic aberration of the lens of the imaging optical system. In consideration of such characteristics, there has been proposed an imaging apparatus that realizes correction of the focus lens position with a simple mechanism (see Patent Document 2).

JP 11-239356 A JP 2006-033716 A

  In autofocus (AF) control of an imaging apparatus such as a video camera, an AF evaluation value signal indicating the sharpness (contrast state) of a video signal generated using an imaging element is generated, and AF evaluation is performed on the AF evaluation value signal. The TV-AF system that searches for the position of the focus lens that maximizes the value is the mainstream. In such a TV-AF system, if it is far from the in-focus position, the high-frequency component of the video signal is reduced, so that it becomes difficult to detect the in-focus position, and a great deal of time is required to obtain the correct in-focus position. It becomes.

  As shown in FIG. 5 described above, the in-focus position differs by inserting and removing the infrared light removal filter from the optical path, and the in-focus position differs depending on the mixture ratio of the visible light and infrared light components. As a result, when the subject is in focus in the visible light shooting mode and the focus is out of focus as described above when switching to the infrared light shooting mode, it is necessary to obtain a correct in-focus position again. There was a problem that it took a long time.

  The TV-AF focus signal described above generally uses a high-frequency component of a video signal extracted by a bandpass filter in a certain band. Therefore, in general, when a normal subject image is photographed under sufficient illuminance, the value increases as the focus is achieved as shown in FIG. 13A, and the point where the level is maximum is the in-focus position. It becomes.

  However, in scenes where the sensitivity of the image sensor is increased under low illuminance, the output level of the focus signal decreases as a whole as shown in FIG. There is a tendency to end up. This is fatal in the TV-AF system in which the focus lens is controlled according to the increase / decrease state of the focus signal, and depending on the subject, the in-focus direction cannot be correctly determined, causing a malfunction. It may occur.

  The present invention has been made in view of the above-described problems, and its purpose is to quickly perform focusing when the visible light photographing mode is switched to the infrared light photographing mode, thereby reducing the discomfort of the photographer. is there.

  Another object of the present invention is to enable stable focus adjustment in a shooting mode in which the sensitivity of the image sensor is improved by retracting the infrared light removal filter from the shooting optical path. .

Imaging device according to the present invention includes an imaging optical system including a focus lens, an imaging element for generating an image signal of an object image formed by the imaging optical system and photoelectrically converted, the light incident to the imaging device An infrared light removing filter for removing the contained infrared light component, filter driving means for moving the infrared light removing filter in and out of the optical path of the imaging optical system, and a high-frequency component of the imaging signal obtained from the imaging element. A focus signal detecting means for taking out as a focus signal and reciprocatingly driving the focus lens to search for a focus direction, continuously moving the focus lens in the focus direction so that the focus signal reaches a peak. and a focus adjustment unit that performs focus adjustment by driving the focus lens, the focus adjusting means, by the filter drive means, the infrared light removed Fi If the data is out on an optical path of the imaging optical system, a shift direction of the focus position when a pre-stored the infrared light removal filter in the storage means is out on an optical path of the imaging optical system Based on this, the focus lens is continuously moved in a predetermined direction to search for a focal position .

  According to the present invention, it is possible to quickly perform focusing when switching from the visible light photographing mode to the infrared light photographing mode, and to reduce the discomfort of the photographer.

  In addition, it is possible to perform stable focus adjustment in an imaging mode in which the sensitivity of the image sensor is improved by retracting the infrared light removal filter from the imaging optical path.

1 is a block diagram showing a configuration of a main part of a video camera as an imaging apparatus according to a first embodiment of the present invention. 3 is a flowchart showing AF control processing in the first embodiment executed by the microcomputer 114 in FIG. 1. The flowchart which shows the TV-AF process performed in FIG. The flowchart which shows the TV-AF restart process performed in FIG. The figure which shows the example of the correction amount of a focus lens position when moving an infrared light removal filter out of an optical path. The figure for demonstrating the micro drive of the focus lens performed in TV-AF process. The figure for demonstrating the hill-climbing drive of the focus lens performed in TV-AF process. 7 is a flowchart showing a modification of the AF control process in the first embodiment executed by the microcomputer 114 in FIG. 1. The flowchart which shows AF control processing in 2nd Embodiment which the microcomputer 114 in FIG. 1 performs. 10 is a flowchart showing a one-shot operation executed in the TV-AF process of FIG. The flowchart which shows AF control processing in 3rd Embodiment which the microcomputer 114 in FIG. 1 performs. 9 is a flowchart showing a modification of AF control processing in the third embodiment executed by the microcomputer 114 in FIG. 1. The figure which shows the example of the focus signal at the time of sufficient illumination intensity and low illumination intensity. The flowchart of TV-AF control in 4th and 6th embodiment. The flowchart of the micro drive mode in 4th Embodiment. The flowchart of a hill-climbing drive mode. The flowchart of the micro drive mode in 5th Embodiment. 20 is a flowchart of TV-AF control in the sixth embodiment. The flowchart of the micro drive mode in 6th Embodiment. The flowchart of the micro drive mode in 7th Embodiment.

(First embodiment)
<Configuration of imaging device>
First, the imaging device according to the first embodiment of the present invention will be described. In the present embodiment, the imaging device is a video camera, but is not limited to a video camera and may be another imaging device such as a digital still camera.

  FIG. 1 is a block diagram illustrating a configuration of a main part of a video camera as an imaging apparatus according to the present embodiment. In FIG. 1, reference numeral 101 denotes a first fixed lens group, reference numeral 102 denotes a variable magnification lens that moves in the optical axis direction to perform variable magnification, and can change the focal length, and reference numeral 103 denotes an aperture. Reference numeral 104 denotes a second fixed lens group, and reference numeral 105 denotes a focus compensator lens (hereinafter referred to as a focus lens) having both a function of correcting the movement of the focal plane due to zooming and a focusing function. The first fixed lens group 101, the variable magnification lens 102, the stop 103, the second fixed lens group 104, and the focus lens 105 constitute an imaging optical system.

  Reference numeral 117 denotes an infrared light removal filter that removes an infrared light component from light incident from a subject. The infrared light removal filter 117 can be moved out of the optical path of the imaging optical system by a filter driving source 118. Reference numeral 106 denotes an image sensor as a photoelectric conversion element constituted by a CCD sensor or a CMOS sensor. The image sensor 106 captures a subject image formed by the imaging optical system and outputs a video signal. Reference numeral 107 denotes a CDS / AGC circuit that samples the output of the image sensor 106 and adjusts the gain.

  A camera signal processing circuit 108 performs various image processing on the output signal from the CDS / AGC circuit 107 to generate a video signal. Reference numeral 109 denotes a monitor constituted by an LCD or the like, which displays a video signal from the camera signal processing circuit 108. A recording unit 115 records the video signal from the camera signal processing circuit 108 on a recording medium such as a magnetic tape, an optical disk, or a semiconductor memory.

  Reference numeral 110 denotes a zoom drive source for moving the variable magnification lens 102. Reference numeral 111 denotes a focusing drive source for moving the focus lens 105. The zoom drive source 110 and the focusing drive source 111 are configured by actuators such as a stepping motor, a DC motor, a vibration motor, and a voice coil motor. Reference numeral 118 denotes a filter driving source which is a motor for moving the infrared light removal filter 117 in and out of the optical path of the imaging optical system.

  Each of the above driving sources is controlled by a driving command from a camera / AF microcomputer (hereinafter referred to as a microcomputer) 114 described later. The positions of the lenses and filters driven by the respective driving sources are detected by position detection means (not shown) and used for various controls by the microcomputer 114. As the position detecting means, a sensor for detecting the position may be provided. When a stepping motor is used as a driving source, the microcomputer 114 counts the number of driving pulses for driving the stepping motor. The position may be detected.

  Reference numeral 112 denotes an AF gate that passes only signals in a region used for focus detection among output signals of all pixels from the CDS / AGC circuit 107. The AF signal processing circuit 113 extracts a high frequency component, a luminance difference component (difference between the maximum value and the minimum value of the luminance level of the signal that has passed through the AF gate 112), and the like from the signal that has passed through the AF gate 112, and the AF evaluation value signal (Focus signal detection). The AF evaluation value signal is output to the microcomputer 114. The AF evaluation value signal represents the sharpness (contrast state) of the video signal generated based on the output signal from the image sensor 106. The sharpness changes depending on the focus state of the image pickup optical system. Specifically, the AF evaluation value signal is a signal representing the focus state of the imaging optical system.

  The microcomputer 114 controls the operation of the entire video camera and performs AF control for moving the focus lens 105 by controlling the focusing drive source 111. The microcomputer 114 performs AF control in the TV-AF method (hereinafter simply referred to as TV-AF) as AF control.

  Reference numeral 116 denotes an operation mode switch, which is operated when the photographer switches between the visible light photographing mode and the infrared light photographing mode. When the infrared light photographing mode is selected, the filter drive source 118 is controlled by the microcomputer 114, the infrared light removal filter 117 is moved out of the optical path of the image pickup optical system, and the image pickup apparatus is moved to the infrared light. Shooting conditions suitable for optical shooting are set. On the other hand, when the visible light imaging mode is selected, the infrared light removal filter 117 is moved on the optical path, and the imaging device is set to imaging conditions suitable for visible light imaging.

  In the above description, the infrared light removal filter 117 is moved by the filter drive source 118 in accordance with the switching of the operation mode changeover switch. However, the filter moving means and the operation mode switching means are defined as a common member as follows. It is good also as composition to do. That is, when a lever or the like for manually moving the infrared light removal filter 117 in and out of the optical path is provided in place of the filter driving source 118 and the photographer operates the lever to move the filter out of the optical path, a filter position detection (not shown) is performed. The movement of the filter is detected by the microcomputer 114, and the operation mode is switched to the infrared light imaging mode. Conversely, when the filter is moved on the optical path by lever operation, the operation mode is switched to the visible light photographing mode. In this way, it is not necessary to provide a motor as the filter driving means, and the size and cost of the imaging apparatus can be reduced.

  The infrared LED (infrared light projection unit) 119 is driven to emit light in response to an instruction from the microcomputer 114, and can project infrared light onto a subject to obtain an infrared image. The light emission ON / OFF instruction is input by the photographer through an operation member (not shown).

<AF Control Processing in First Embodiment>
Next, AF control processing executed by the microcomputer 114 will be described. FIG. 2 is a flowchart showing an AF control process executed by the microcomputer 114 in FIG. This process is executed in accordance with a computer program stored in the microcomputer 114, and is repeatedly executed, for example, at the readout cycle of the imaging signal from the imaging device 106 for generating one field image.

  In FIG. 2, first, in S201, it is determined whether or not the infrared light removal filter 117 has inserted / removed or removed / inserted on the optical path. That is, it is determined whether or not the mode has been changed from the visible light shooting mode to the infrared light shooting mode, or from the infrared light shooting mode to the visible light shooting mode. If it has been inserted or removed, that is, if the shooting mode has changed, the process proceeds to S205, and if there is no insertion or removal and the shooting mode has not changed, the process proceeds to S202.

  In S205, it is determined whether or not the infrared light removal filter 117 has been inserted into and removed from the optical path, that is, whether or not the visible light photographing mode has shifted to the infrared light photographing mode. When the infrared light removal filter 117 is inserted into and removed from the optical path, that is, when the visible light photographing mode is shifted to the infrared light photographing mode, the drive direction of the focus lens 105 is set to infinity in S206. When the infrared light removal filter 117 is removed from the optical path and inserted, that is, when the infrared light photographing mode is shifted to the visible light photographing mode, the driving direction of the focus lens 105 is set to the closest direction in S207.

  This is due to the following reason. In the case of the characteristics as shown in FIG. 5, when the infrared light removal filter 117 is inserted on the optical path and then removed, the correction amount is in the minus direction, so that the focus position (focal position) is in the infinity direction. I understand. Therefore, when the infrared light removal filter 117 is inserted on the optical path and removed, that is, when the visible light photographing mode is shifted to the infrared light photographing mode, the driving direction (correction direction) of the focus lens 105 is set to the infinity direction. Set it. In the reverse case, for the same reason, the driving direction of the focus lens 105 may be set to the close direction opposite to the infinity direction.

  In S208, the hill-climbing drive mode is set by TV-AF control described later. This hill-climbing drive mode will be described later. In step S209, an insertion / extraction flag is set, and TV-AF control in step S210 to be described later is executed.

  Here, the process described above is a process that is a feature of the present embodiment, and the infrared light removal filter 117 has been inserted / removed or removed / inserted on the optical path, that is, from the visible light photographing mode to the red state. When the mode is changed to the external light shooting mode, or when the infrared light shooting mode is changed to the visible light shooting mode, the in-focus position is changed as described above. Here, when searching for the in-focus direction from the micro drive mode (the micro drive mode will be described later) and trying to obtain the in-focus position, the high-frequency component of the video signal is reduced if the focus position is greatly deviated. Therefore, it becomes difficult to detect the in-focus position, and much time is required to obtain the correct in-focus position. For this reason, the AF control characteristic is made to increase the response, that is, by forcibly shifting to the hill-climbing drive mode, the in-focus position can be obtained quickly. Further, the focus lens 105 is moved to the in-focus position by storing the shift direction (correction direction) of the in-focus position when the infrared light removal filter 117 is inserted and removed on the optical path in a non-illustrated nonvolatile memory or the like. It becomes possible to move quickly in the direction.

  Further, here, when the infrared light removal filter 117 is inserted into and removed from the optical path, that is, when the visible light photographing mode is shifted to the infrared light photographing mode, the moving direction of the focus lens 105 is moved to the infinity direction. Conversely, when the infrared light removal filter 117 is removed from the optical path and inserted, that is, when the infrared light photographing mode is shifted to the visible light photographing mode, the focus lens 105 is moved in the closest direction. However, since this moving direction may change depending on the optical characteristics, it may be set according to the optical characteristics of the imaging apparatus, and may be set according to the focal length.

  Next, in S201, if the infrared light removal filter 117 does not insert / extract on the optical path and the photographing mode has not changed, the process proceeds to S202, where it is determined whether the insertion / extraction flag is set. judge. When the insertion / removal flag is set, the infra-red light removal filter 117 is inserted / removed on the optical path and the photographing mode is changed, so that the in-focus position is being searched for in the hill-climbing drive mode. Therefore, the process proceeds to S210 and the hill-climbing drive mode is continuously executed by TV-AF control.

  Conversely, when the insertion / extraction flag is not set, normal TV-AF control is being executed. In that case, it transfers to S203 and it is determined whether infrared LED119 was operated ON / OFF. When the ON / OFF operation is performed, the process proceeds to S204. If the ON / OFF operation has not been performed, the process proceeds to S210 and TV-AF control is executed.

In S204, a forced restart flag is set. This is because when the infrared LED 119 is turned ON / OFF, the in-focus position is changed by changing the component ratio of visible light and infrared light. For this reason, by setting a forced restart flag, an operation for re-focusing is executed in the TV-AF control described later. As a result, the focus position changes depending on ON / OFF of the infrared LED 119, but the change of the AF evaluation value is small, and it is possible to prevent the focus lens from being stopped unintentionally and remaining out of focus. it can.

3 and 4 are flowcharts showing the TV-AF process executed in S210 in FIG.

  In FIG. 3, first, an AF evaluation value is acquired from an image signal (S301). Then, a TV-AF restart determination process described later with reference to FIG. 4 is performed (S302). Next, it is determined whether or not the TV-AF mode is the minute drive mode (S303). The minute drive mode will be described later. As a result of the determination in S301, when the mode is the minute drive mode (YES in S303), the focus lens 105 is minutely driven (S304). The minute driving will be described later with reference to FIG.

  Next, it is determined whether or not it is in focus (S305). If the result of determination in S305 is in-focus (YES in S305), driving of the focus lens 105 is stopped (S309). Next, the AF evaluation value at the in-focus position of the focus lens 105 is stored in a memory (not shown) of the microcomputer 114 (S310). Next, the current mode is shifted to the restart mode (S311).

  As a result of the determination in S305, if the in-focus state is not obtained (NO in S305), it is determined in which direction the in-focus position is with respect to the current position of the focus lens 105 (S306). Next, in S307, it is determined whether or not the direction of the in-focus position (hereinafter referred to as the in-focus direction) has been determined (S307).

  If the in-focus direction can be determined as a result of the determination in S307 (YES in S307), the TV-AF mode is shifted to the hill-climbing drive mode (S308). If the result of the determination in S303 is that the mode is not the minute drive mode (NO in S303), it is determined whether or not the mode is the hill-climbing drive mode (S312).

  As a result of the determination in S312, when the mode is the hill-climbing drive mode (YES in S312), the focus lens 105 is hill-climbed (focus position detection control) at a predetermined speed (S313). Next, it is determined whether or not the AF evaluation value exceeds the peak in the hill-climbing drive of the focus lens 105 (S314). If the AF evaluation value exceeds the peak as a result of the determination in S314 (YES in S314), the focus lens 105 is placed at a position where the AF evaluation value has peaked in the hill-climbing driving of the focus lens 105 (hereinafter referred to as a peak position). Return (S315).

  Next, it is determined whether or not the focus lens 105 has returned to the peak position (S316). As a result of the determination in S316, when the peak position is returned (YES in S316), the TV-AF mode is shifted to the minute drive mode (S317). In step S322, the insertion / extraction flag is cleared. Thereby, it can be determined that the search for the in-focus position in the hill-climbing drive mode is completed due to the infrared light removal filter 117 being inserted and removed on the optical path and the photographing mode being changed.

  If the result of determination in S312 is that the mode is not the hill-climbing drive mode (NO in S312), the current mode is the restart mode, the process proceeds to S318, and the restart flag is determined by the TV-AF restart determination process in S302 described later. Determine if is set. When the restart flag is not set (NO in S318), the driving of the focus lens 105 is stopped (S319).

  As a result of the determination in S318, if the restart flag is set (YES in S318), the TV-AF mode is shifted to the minute drive mode (S320). Then, the restart flag is cleared (S321).

  FIG. 4 is a flowchart showing the TV-AF restart determination process in S302 of FIG.

  First, in S401, it is determined whether the forced restart flag is set. When the forced restart flag is set, the infrared LED 119 is turned ON / OFF in FIG. 2 and the in-focus position is shifted, so the TV-AF control is restarted from the initial state. For this purpose, the process proceeds to S407, data used in the TV-AF control is initialized, and the process proceeds to the minute drive mode in S408. Then, the process proceeds to S409, and the forced restart flag is cleared.

  If the forced restart flag is not set in S401, the process proceeds to S402. Here, the AF evaluation value stored in the memory (not shown) of the microcomputer 114 is compared with the latest AF evaluation value, and whether or not these differences are larger than a predetermined value, that is, the AF evaluation value. It is determined whether or not there is a large fluctuation in. If the AF evaluation value fluctuates as a result of the determination in S402 (YES in S402), it is determined whether or not the hill-climbing drive mode is set (S403).

  If the result of determination in S403 is that the mode is not the hill-climbing drive mode (NO in S403), the restart process is executed, or if the mode is the micro drive mode, the TV-AF process is performed to restart the micro drive from the initial state again. The data to be used is initialized (S404). Then, the process proceeds to S405. If the result of determination in S403 is that it is a hill-climbing drive mode (YES in S403), the process proceeds to S405.

  Next, in S405, it is determined whether or not it is a restart mode. If the result of determination in S405 is that it is a restart mode (YES in S405), a restart flag is set (S406). Then, the process ends. If the result of determination in S405 is not a restart mode (NO in S405), the process ends. As a result of the determination in S402, when the AF evaluation value fluctuates little (NO in S402), the process is terminated as it is.

  FIG. 6 is a view for explaining the minute driving of the focus lens 105 executed in S304 in the TV-AF process of FIG. In FIG. 6, the horizontal axis indicates time, and the vertical axis indicates the position of the focus lens 105. In the upper part of the figure, a vertical synchronizing signal of the video signal is shown.

  As shown in FIG. 6, an AF evaluation value EVA for charges accumulated in the image sensor 106 during the period A (indicated by the slanted ellipse in the figure) is taken in at time TA, and is input to the image sensor 106 during the period B. An AF evaluation value EVB for the accumulated charge is taken in at time TB. Further, the AF evaluation value EVC for the electric charge accumulated in the image sensor 106 during the period C is captured at time TC. At time TD, the AF evaluation values EVA, EVB, and EVC are compared, and if EVA> EVB and EVB> EVC, the driving (vibration) center (center position) of the minute driving is moved. On the other hand, if EVA <EVB or EVB <EVC, the vibration center is not moved. In this way, the micro drive is used to determine the direction in which the AF evaluation value increases while moving the focus lens 105, or to search for the position (peak position) of the focus lens 105 where the AF evaluation value is the largest.

  Note that the control for driving the focus lens 105 minutely (minutely reciprocating) in order to determine whether or not it is in focus from the change in AF evaluation value can also be referred to as focus confirmation control. Also, the control for finely driving the focus lens 105 to determine the in-focus direction from the change in the AF evaluation value can be referred to as in-focus direction discrimination control.

  FIG. 7 is a diagram for explaining the hill-climbing drive of the focus lens 105 executed in S313 in the TV-AF process of FIG. In FIG. 7, the horizontal axis indicates the position of the focus lens 105, and the vertical axis indicates the AF evaluation value.

  As shown in FIG. 7, in the movement of A, since the AF evaluation value decreases after exceeding the peak, the presence of the peak position (focus position) can be confirmed. In this case, after the focus lens 105 is returned to the vicinity of the peak position, the hill-climbing drive is terminated, and the process shifts to the minute drive. On the other hand, in the movement of B, since there is no peak and the AF evaluation value decreases monotonously, it can be determined that the driving direction of the focus lens 105 is incorrect. In this case, the driving direction of the focus lens 105 is reversed and the hill-climbing driving is continued. In this way, driving the focus lens 105 and determining the peak position where the AF evaluation value obtained during that time reaches a peak or its vicinity is hill-climbing driving.

  FIG. 8 is a flowchart showing a modification of the AF control process executed by the microcomputer 114 in FIG. Since this process is basically the same as the AF control process in FIG. 2, the operations common to those in FIG. 2 are omitted with the last two digits being the same as those in FIG. 2, and only different operations are described.

  First, in step S801, it is determined whether the infrared light removal filter 117 has inserted / removed or removed / inserted on the optical path. That is, it is determined whether or not the mode has been changed from the visible light shooting mode to the infrared light shooting mode, or from the infrared light shooting mode to the visible light shooting mode. If there is insertion / extraction, that is, if the shooting mode is changed, the process proceeds to S824. If there is no insertion / extraction and the shooting mode is not changed, the process proceeds to S821.

  In step S824, an offset amount for moving the focus lens 105 is set. In FIG. 5 described above, it can be seen that the position correction amount of the focus lens 105 is larger than that at the time of insertion by removing the infrared light removal filter 117 on the optical path even in visible light. It can be seen that the correction amount decreases as the infrared light component increases. Therefore, since the focus position does not become larger than the correction amount of L1 for only visible light, the focus direction can be easily specified by moving the focus lens 105 by the maximum correction amount in advance. it is conceivable that. Therefore, although not shown, an offset amount corresponding to the focal length is stored in advance in a nonvolatile memory, and the offset amount of the focus lens 105 is set from the current focal length.

  Next, in S825, the infrared light removal filter 117 performs an insertion → removal or removal → insertion operation on the optical path. That is, the infrared light photographing mode is changed to the visible light photographing mode, or the infrared light photographing mode is visible. The focus lens position before the transition to the optical photographing mode is stored, and the offset amount set in S824 is added to the focus lens position to set the target position of the focus lens. In step S826, a focus lens offset driving flag is set. In step S827, the focus lens 105 is driven to the target position set in step S825.

  While the focus lens 105 is being driven to the target position, the process proceeds from S801 to S821. In S821, it is determined whether the focus lens offset driving flag is set. If the focus lens offset driving flag is set, the process proceeds to S822, and conversely, the focus lens offset driving flag is set. If it is not set, the process proceeds to S802, and the same processing as in FIG. 2 is executed.

  In S822, it is determined whether the focus lens 105 has reached the target position of the focus lens set in S825. If the focus lens 105 has not reached the target position, the process proceeds to S827 and the focus lens 105 is continuously driven. If it is determined that the focus lens 105 has reached the target position, the process proceeds to S823, the focus lens offset driving flag is cleared, and the process proceeds to S805.

  The processes after S805 are the same as those in FIG. However, in S805, it is determined whether or not the infrared light removal filter 117 has been inserted into and removed from the optical path, that is, whether or not the visible light photographing mode has shifted to the infrared light photographing mode. The driving direction of the lens is reversed. In other words, when the infrared light removal filter 117 is inserted into and removed from the optical path, that is, when the visible light photographing mode is shifted to the infrared light photographing mode, the driving direction of the focus lens 105 is set to the closest direction in S828. When the infrared light removal filter 117 is removed from the optical path and inserted, that is, when the infrared light photographing mode shifts to the visible light photographing mode, the driving direction of the focus lens 105 is set to the infinity direction in S829. .

  As described above, this is because the infrared light removing filter 117 is inserted into the optical path, removed, or removed, and inserted, that is, the visible light photographing mode is shifted to the infrared light photographing mode, or the infrared light photographing mode. This is because the focus lens 105 is moved by the focus lens position correction amount corresponding to the visible light of L1 in FIG. Thereby, when the infrared light removal filter 117 is inserted into and removed from the optical path, that is, when the visible light photographing mode is shifted to the infrared light photographing mode, the in-focus position is closest depending on the ratio of the infrared light component. Therefore, the driving direction of the focus lens 105 is set to the closest direction, and hill-climbing driving is executed. In the opposite case, that is, when the infrared light removal filter 117 is removed from the optical path and inserted, that is, when the infrared light photographing mode is shifted to the visible light photographing mode, the driving direction is reversed as compared with FIG. It is clear that

  Here, in FIGS. 2 and 8, when the insertion / extraction flag is set, the focus lens 105 is driven in the hill-climbing driving process of S313 in FIG. 3 compared to when the insertion / extraction flag is not set. You may increase the speed. As a result, it is possible to reduce the time until the in-focus position is found, and it is possible to move quickly to the in-focus position. When the drive speed of the focus lens 105 when the insertion / removal flag is not set is α1 (mm / s), and when the insertion / removal flag is set, the drive speed α2 of the focus lens 105 is expressed by Equation (1). Can be expressed as

α2 = α1 * 2 (1)
For example, it is assumed that when the insertion / extraction flag is not set, the driving speed of the focus lens 105 is set to a driving speed that moves 1/4 of the focal depth in one field period. In this case, when the insertion / removal flag is set, the driving speed of the focus lens 105 is a driving speed that moves 1/2 times the focal depth in one field period. However, the values are not limited to those described above.

<Advantages in First Embodiment>
As described above, the infrared light removal filter 117 performs insertion → removal or removal → insertion operation on the optical path, that is, the transition from the visible light photographing mode to the infrared light photographing mode, or the visible light from the infrared light photographing mode. When shifting to the shooting mode, the in-focus position changes. That is, since the in-focus state is changed to the out-of-focus state, it is necessary to reduce the time during which the focus is out of focus by changing the AF control to a response-responsive control. Here, if the minute drive mode is executed by the TV-AF control, it takes time to find the in-focus direction. Therefore, in a transient state immediately after the shooting mode is changed, as a control for increasing the responsiveness of the AF control, the mode is forcibly shifted to the hill-climbing drive mode, and the focus lens 105 is moved in a predetermined direction so that the focus position can be quickly adjusted. Can be explored. As a result, it is possible to reduce the time that the focus is out of focus and reduce the discomfort of the photographer. When a predetermined time has elapsed from the transient state immediately after the shooting mode is changed and the steady state is reached, the AF control is returned to the original state.

  Further, since the ratio of the visible light component and the infrared light component differs depending on ON / OFF of the infrared LED 119, the in-focus position changes. Therefore, it is possible to maintain a stable in-focus state by restarting the TV-AF control by turning on / off the infrared LED 119.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. The hardware configuration in the second embodiment is the same as that described with reference to FIG. 1 in the first embodiment.

<AF Control Processing in Second Embodiment>
An AF control process executed by the microcomputer 114 in the second embodiment will be described. FIG. 9 is a flowchart showing an AF control process executed by the microcomputer 114 in FIG. Since this process is basically the same as the AF control process in the first embodiment, the operations common to those in FIG. 2 are omitted with the last two digits being the same as those in FIG. 2, and only the different operations are described. To do.

  In the present embodiment, the infrared light removal filter 117 performs an insertion → removal or removal → insertion operation on the optical path, that is, the transition from the visible light photographing mode to the infrared light photographing mode, or the visible light from the infrared light photographing mode. When shifting to the shooting mode, the one-shot operation is executed.

  First, in step S901, it is determined whether or not the infrared light removal filter 117 has performed an operation of inserting → removing or removing → inserting on the optical path. That is, it is determined whether or not the mode has been changed from the visible light shooting mode to the infrared light shooting mode, or from the infrared light shooting mode to the visible light shooting mode. If there has been insertion / extraction, that is, the shooting mode has changed, the process proceeds to S905. If there is no insertion / extraction and the shooting mode has not changed, the process proceeds to S902.

  In step S <b> 905, it is determined whether the infrared light removal filter 117 has been inserted on the optical path and removed, that is, whether the visible light photographing mode has shifted to the infrared light photographing mode. When the infrared light removal filter 117 is inserted into and removed from the optical path, that is, when the visible light photographing mode is shifted to the infrared light photographing mode, the drive direction of the focus lens 105 is set to infinity in S906. When the infrared light removal filter 117 is removed from the optical path and inserted, that is, when the infrared light photographing mode is shifted to the visible light photographing mode, the driving direction of the focus lens 105 is set to the closest direction in S907.

  Next, in S909, the insertion / extraction flag is cleared. In step S931, the one-shot operation end flag is cleared, a flag indicating whether the one-shot operation is being executed is cleared, and the one-shot operation is started.

  Next, a one-shot operation described later is executed in S932. This is a characteristic process in the present embodiment, which is changed to control that increases the responsiveness of AF control. That is, by performing the one-shot operation, the focus lens 105 is largely moved within the driving range, and an approximate focus position is searched (coarse search). Thereafter, in order to obtain a final in-focus position, the driving speed of the focus lens 105 is set slower than that in the rough search, and a peak position having a large AF evaluation value is searched (micro search). Thereby, a focus position can be obtained quickly.

  In S933, it is determined whether or not the one-shot operation is finished. If the one-shot operation is finished, the insertion / extraction flag is cleared in S934. If the one-shot operation is not finished, the process is finished. The one-shot operation is continued at the next processing timing.

  In S902, it is determined whether the insertion / extraction flag is set. If the insertion / extraction flag is set, the one-shot operation has not been completed, so the process proceeds to S932 and the one-shot operation is continued. When the insertion / extraction flag is not set, the one-shot operation is completed, and the infrared light removal filter 117 is inserted into the optical path, removed, or removed, and inserted, that is, the visible light photographing mode is changed to the infrared light photographing mode. This means that the in-focus position at the time of transition or the transition from the infrared light photographing mode to the visible light photographing mode is obtained.

  If the insertion / extraction flag is not set in S902, the process proceeds to S903. The subsequent processing is the same as in the first embodiment described above, and executes TV-AF control, and restarts TV-AF control depending on whether the infrared LED 119 is turned on or off. Determine whether or not.

  FIG. 10 is a flowchart showing the one-shot operation executed in S932 in FIG.

  First, an AF evaluation value is acquired in S1001. In step S1002, it is determined whether the mode is the coarse search mode. If it is in the coarse search mode, the process proceeds to S1003. In S1003, the first driving direction is set as the driving direction of the focus lens. In S1004, the focus lens drive speed is set to the first drive speed.

  In step S1005, it is determined whether the AF evaluation value is lowered or hits the edge. As a result of the determination in S1005, when the AF evaluation value is lowered or hits the edge, the process proceeds to S1006, and the process moves to the fine search mode, and the AF evaluation value is not lowered or does not hit the edge. , The process is terminated, and the coarse search mode is continued.

  If it is determined in S1002 that the mode is not the coarse search mode, the process proceeds to S1007 to determine whether the mode is the fine search mode. If the result of determination in S1007 is that it is in the fine search mode, the flow proceeds to S1008, and if not, the flow proceeds to S1012.

  In step S1008, the second driving direction opposite to the first driving direction is set as the driving direction of the focus lens. In step S1009, the second driving speed slower than the first driving speed is set as the driving speed of the focus lens.

  Here, the drive direction set in S906 or S907 in FIG. 9 is set as the first drive direction of the focus lens. Further, the first and second driving speeds are set as follows, for example. That is, the drive speed is set so that the amount by which the focus lens 105 moves in the period at which the AF evaluation value is acquired for the first drive speed is greater (twice) than the depth of focus. The second driving speed is set so that the amount by which the focus lens 105 moves in the period of acquiring the AF evaluation value is smaller (1/2 times) than the focal depth.

  In S1010, it is determined whether the AF evaluation value has exceeded the peak or has hit the end. As a result of the determination in S1010, when the AF evaluation value exceeds the peak or hits the end, the process proceeds to S1011 and the peak position return mode is performed. If the AF evaluation value does not exceed the peak and does not hit the end, the process is terminated and the minute search mode is continued.

  In S1012, the peak position return mode is set, and when it is determined that the AF evaluation value exceeds the peak in the fine search mode, the focus lens is moved to the peak position of the obtained AF evaluation value. If it hits the edge in the minute search mode, the AF evaluation value peak position cannot be found, and the subject has no contrast. Therefore, the focus lens 105 is moved to the focus lens position or the end position before the one-shot operation is performed. Let

  In step S1013, it is determined whether the focus lens 105 has returned to the peak position. If the result of determination in S1013 is that the focus lens 105 has not returned to the peak position, the processing is terminated and the peak position return mode is continued. Conversely, when the focus lens 105 returns to the peak position, the focus lens is stopped in S1014, a one-shot operation end flag is set in S1015, and the one-shot operation is ended.

  Here, the second embodiment may be combined with the modification of the AF control process shown in FIG. 8 in the first embodiment described above.

<Advantages in Second Embodiment>
As described above, the infrared light removal filter 117 performs insertion → removal or removal → insertion operation on the optical path, that is, the transition from the visible light photographing mode to the infrared light photographing mode, or the visible light from the infrared light photographing mode. When shifting to the shooting mode, the in-focus position changes. That is, the focused state is changed to the blurred state. Therefore, it is necessary to reduce the time when the focus is out of focus by increasing the responsiveness of the AF control. Here, if normal TV-AF control is executed, it takes time to find the in-focus position. Therefore, the focus lens can be moved to a position where the AF evaluation value peaks at high speed with high accuracy by executing the one-shot operation as a means for changing the AF control characteristic to a characteristic that increases the responsiveness. As a result, it is possible to reduce the time that the focus is out of focus and reduce the discomfort of the photographer.

(Third embodiment)
Next, a third embodiment of the present invention will be described. The hardware configuration in the third embodiment is the same as that described with reference to FIG. 1 in the first embodiment.

<AF Control Processing in Third Embodiment>
An AF control process executed by the microcomputer 114 in the third embodiment will be described. FIG. 11 is a flowchart showing an AF control process executed by the microcomputer 114 in FIG. Since this process is basically the same as the AF control process in the first embodiment, the operations common to those in FIG. 2 are omitted with the last two digits being the same as those in FIG. 2, and only the different operations are described. To do.

  In the present embodiment, the infrared light removal filter 117 performs an insertion → removal or removal → insertion operation on the optical path, that is, the transition from the visible light photographing mode to the infrared light photographing mode, or the visible light from the infrared light photographing mode. When shifting to the shooting mode, the TV-AF control is re-executed to increase the amount of movement of the focus lens 105 during minute driving.

  First, in S1101, it is determined whether or not the infrared light removal filter 117 has performed an operation of inserting → removing or removing → inserting on the optical path. That is, it is determined whether or not the mode has been changed from the visible light shooting mode to the infrared light shooting mode, or from the infrared light shooting mode to the visible light shooting mode. If there is an insertion / extraction, that is, the shooting mode is changed, the process proceeds to S1144. If there is no insertion / extraction and the shooting mode is not changed, the process proceeds to S1102.

  In S1144, the large amplitude flag is set. In step S1145, a forced restart flag is set. This is a characteristic process in the present embodiment. When this large amplitude flag is set, although not shown, the focus lens 105 in the minute drive of S304 is included in the TV-AF control process in FIG. 3 described above. Increase the amount of movement per time. Assuming that the amount of movement of the focus lens 105 during normal micro-drive is β1, when the large amplitude flag is set, the amount of movement β2 of the focus lens 105 is set as shown in Expression (2). .

β2 = β1 * 2 (2)
For example, if the amount of movement β1 of the focus lens 105 during normal micro drive is set to ¼ of the focal depth, the amount of movement β2 of the focus lens 105 once when the large amplitude flag is set. Is set to ½ of the depth of focus. However, it is not necessarily limited to the above-described formula (2). This makes it difficult to detect the in-focus position when there is a large deviation from the in-focus position, because the high-frequency component of the video signal is reduced. By increasing the amount of movement of the focus lens 105 once, AF evaluation is performed. Increase the amount of change in value to make it easier to find the in-focus direction. And the time for obtaining the correct in-focus position is reduced. Further, since the in-focus position changes, the TV-AF control is restarted by setting a forced restart flag. Thereby, a change in the AF evaluation value is small, and it is possible to prevent the focus lens from being unintentionally stopped and being out of focus.

  In S1146, the insertion / extraction count is cleared, an insertion / extraction flag is set in S1147, and TV-AF control (S1110) is executed.

  In step S1102, it is determined whether the insertion / extraction flag is set. If the insertion / extraction flag is set, the process proceeds to S1141, and if the insertion / extraction flag is not set, the process proceeds to S1103. Steps after S1103 are the same as those in the first embodiment.

  In S1141, it is determined whether the insertion / extraction count is greater than a predetermined count value. If the insertion / extraction count is larger than the predetermined count value, the process proceeds to S1142, the insertion / extraction flag is cleared, and the large amplitude flag is cleared in S1148. Conversely, if the insertion / extraction count is equal to or smaller than the predetermined count value, the process proceeds to S1143, and the insertion / extraction count is counted up.

  In this case, the large amplitude flag is cleared when the count value is larger than the predetermined count value. However, the present invention is not limited to this. However, although not shown, the focus is determined in S305 in FIG. When 105 is stopped, the large amplitude flag may be cleared.

  FIG. 12 is a flowchart showing a modification of FIG. 11 in the AF control process executed by the microcomputer 114.

  Since this process is basically the same as the AF control process shown in FIG. 11, the same operations as those in FIG. 11 are omitted with the last two digits being the same as those in FIG. 2 and FIG. explain.

  In FIG. 12, the infrared light removal filter 117 performs insertion → removal or removal → insertion operation on the optical path, that is, transition from the visible light photographing mode to the infrared light photographing mode, or visible light photographing from the infrared light photographing mode. When the mode is shifted, the TV-AF control is re-executed to increase the driving speed of the focus lens 105 during hill-climbing driving.

  That is, in FIG. 11 described above, the large amplitude flag is set in S1144 and the large amplitude flag is cleared in S1148. In FIG. 12, the large driving speed flag is set in S1251, and the driving is performed in S1252. Clear high speed flag. Thereby, the time until the in-focus position is found is reduced.

  Further, by combining the AF control process shown in FIG. 11 and the AF control process shown in FIG. 12, the direction to the in-focus position can be found quickly, and the in-focus position after the direction to the in-focus position is known. Time to find is reduced.

<Advantages in the third embodiment>
As described above, the infrared light removal filter 117 performs insertion → removal or removal → insertion operation on the optical path, that is, the transition from the visible light photographing mode to the infrared light photographing mode, or the visible light from the infrared light photographing mode. When shifting to the shooting mode, the in-focus position changes. That is, the focused state is changed to the blurred state. Therefore, it is necessary to reduce the time that the focus is out of focus by increasing the responsiveness of the AF control. Here, if normal TV-AF control is executed, it takes time to find the in-focus position. Therefore, the AF control characteristic is a characteristic that increases the responsiveness, and the amount of change in the AF evaluation value is increased by increasing the amount of movement of the focus lens 105 at the time of minute driving, so that the in-focus direction can be found early and the in-focus position is obtained. To reduce the time until. As a result, it is possible to reduce the time that the focus is out of focus and reduce the discomfort of the photographer.

  Similarly, the infrared light removal filter 117 performs insertion → removal or removal → insertion operation on the optical path, that is, the transition from the visible light photographing mode to the infrared light photographing mode, or the visible light from the infrared light photographing mode. When shifting to the photographing mode, the time until the in-focus position is obtained is reduced by increasing the driving speed of the focus lens 105 during hill-climbing driving.

  In addition, the infrared light removal filter 117 performs an insertion → removal or removal → insertion operation on the optical path, that is, the visible light photographing mode is shifted to the infrared light photographing mode, or the infrared light photographing mode is changed to the visible light photographing mode. When the transition is made, the TV-AF control is restarted. As a result, it is possible to prevent the AF evaluation value from changing so little that the image remains out of focus without restarting.

  As described above, in each of the above-described embodiments, the infrared light removal filter 117 performs an operation of insertion → removal or removal → insertion on the optical path, that is, the transition from the visible light photographing mode to the infrared light photographing mode, or When shifting from the infrared light photographing mode to the visible light photographing mode, the AF control characteristic is made to increase the response. As a method of increasing the responsiveness, as described above, the hill-climbing driving mode, or the one-shot operation, increasing the amount of movement of the focus lens 105 during minute driving, and increasing the driving speed of the focus lens 105 during hill-climbing driving are executed. . As a result, it is possible to quickly obtain the in-focus position, the time during which the focus is out of focus is shortened, and the photographer's discomfort can be reduced.

  In addition, by restarting the TV-AF control by turning on / off the infrared LED 119, it follows the change in the in-focus position due to the difference in the ratio between the visible light component and the infrared light component, thereby achieving stable focusing. It becomes possible to keep the state.

  In addition, when the infrared light removal filter 117 is inserted or removed, that is, when the visible light photographing mode and the infrared light photographing mode are switched, the TV-AF control is restarted. Since it does not start, it can be prevented from remaining blurred.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described. The hardware configuration in the fourth embodiment is the same as that described with reference to FIG. 1 in the first embodiment.

  FIGS. 14 and 15 are the drawings that best represent the main points of the present embodiment. The feature is that the TV-AF control mode is changed according to the current shooting mode and the in-focus state, and The control characteristic of the TV-AF is changed depending on whether the control mode is the stability priority mode or the normal mode.

  In the hardware configuration shown in FIG. 1, the microcomputer 114 can switch between the visible light photographing mode and the infrared light photographing mode in accordance with the illuminance condition at the time of photographing. Generally, in order to remove an infrared light component unnecessary for photographing under a sufficient illuminance, the visible light photographing mode is set in which photographing is performed with the infrared light removing filter 117 inserted. In addition, in order to shoot with improved sensitivity of the image sensor 106 under low illuminance, the infrared light shooting mode is set in which the infrared light removal filter 117 is retracted from the imaging optical system.

  Next, an outline of the focus adjustment control performed by the microcomputer 114 will be described with reference to FIGS.

  As described above, FIG. 14 and FIG. 15 are drawings that best represent the main points of the present embodiment, and the feature thereof is that the TV-AF control mode is set in accordance with the current shooting mode and in-focus state. In addition, the control characteristic of the TV-AF is changed depending on whether the control mode is the stability priority mode or the normal mode.

  In FIG. 14, in S1401, it is determined whether the currently set photographing mode is the infrared light photographing mode or the visible light photographing mode. If the current photographing mode is the visible light photographing mode, the process proceeds to S1402. If it is, the process proceeds to S1403. In S1402, the control mode of TV-AF control is set to the normal mode as processing in the visible light photographing mode. In S1403, it is determined whether or not the mode is the minute drive mode. If the mode is the minute drive mode, the process proceeds to S1404. If not, the process proceeds to S1412. In step S1404, a minute driving operation is performed to drive the focus lens with a predetermined amplitude to determine whether the focus lens is in focus or in which direction the focus is present. The detailed operation here will be described with reference to FIG.

  In S1405, it is determined whether or not in-focus determination is performed by the minute driving operation in S1404. If in-focus determination is performed by the minute driving operation, the process proceeds to S1406. Otherwise, the process proceeds to S1408. In S1406, it is determined whether or not the direction can be determined by the minute driving operation in S1404. If the direction can be determined, the process proceeds to S1407 and proceeds to the hill climbing operation. If not, the process returns to S1401 and the minute driving mode is continued. To do.

  In S1408, it is determined again whether the currently set photographing mode is the infrared light photographing mode or the visible light photographing mode. If the photographing mode is the infrared light photographing mode, the process proceeds to S1409. Transits to S1410. In step S1409, as a process in the case where focus determination can be performed in the infrared light shooting mode, the control mode of the TV-AF control is set to the stability priority mode in order to stabilize the subsequent focus adjustment operation.

  In this embodiment, the stability priority mode is set when the focus can be determined in the infrared light shooting mode. It does not matter as a setting.

  In S1410, the focus signal level at the time of in-focus is stored in the memory, and then the process proceeds to S1411 to shift to the restart determination mode. Here, the restart determination mode is a flow for determining whether or not minute driving (direction determination) is performed again (S1420, S1421).

  In S1412, it is determined whether or not the hill-climbing drive mode is selected. If the hill-climbing drive mode is selected, the process proceeds to S1413. Otherwise, the process proceeds to S1417. In S1413, a hill-climbing drive operation is performed, and the focus lens is hill-climbed and driven at a predetermined speed in a direction in which the focus signal increases. The detailed operation here will be described with reference to FIG.

  In S1414, it is determined whether or not the peak position of the focus signal has been found by the hill-climbing drive operation in S1413. If the peak position of the focus signal is found, the process proceeds to S1415. If not, the process returns to S1401 and the hill-climbing drive mode. Continue.

  If it is determined in S1414 that the peak position has been found, the focus determination mode is set after the focus lens is moved to the peak position (S1419). In S1415, after the focus lens position at which the focus signal has reached a peak is set as the target position, the process proceeds to S1416 and the process proceeds to the stop mode.

  In S1417, it is determined whether or not it is the stop mode. If it is the stop mode, the process proceeds to S1418, and if not, the process proceeds to S1420. In S1418, it is determined whether or not the focus lens has returned to the position where the focus signal reaches the peak. If so, the process proceeds to S1419 to shift to the minute drive (focus determination) mode, and otherwise to S1401. Continue return stop mode.

  In S1420, the current focus signal level is compared with the focus signal level held in S1410, and it is determined whether or not the fluctuation amount is larger than a predetermined value. If it is determined that the fluctuation amount is large, the process proceeds to S1421, and the mode is shifted to the minute drive (direction determination) mode. If not, the process returns to S1401 and the restart determination mode is continued.

  In FIG. 15, in S1501, it is determined whether the counter indicating the operation state of minute driving is currently 0. If so, the process proceeds to S1502, and if not, the process proceeds to S1503. In S1502, the current focus signal level is held as processing when the focus lens 105 is on the close side. The focus signal here is based on an image signal generated from charges accumulated in the image sensor 106 when the focus lens 105 is on the infinity side in S1510 described later.

  In S1503, it is determined whether or not the current counter is 1. If so, the process proceeds to S1504, and if not, the process proceeds to S1509. In S1504, a vibration amplitude and a center movement amplitude for driving the focus lens 105 in S1508 described later are calculated. Usually, these amplitudes are set within the depth of focus. In S1505, the focus signal level on the infinity side held in S1502 is compared with the focus signal level on the near side held in S1510, which will be described later. If the former is large, the process proceeds to S1506, and if the latter is large, the process proceeds to S1507.

  In S1506, the vibration amplitude and the center movement amplitude are added to obtain a drive amplitude. In S1507, the vibration amplitude is set as the drive amplitude. In S1508, driving is performed in an infinite direction based on the driving amplitude obtained in S1506 or S1507. In S1509, it is determined whether or not the current counter is 2. If so, the process proceeds to S1510, and if not, the process proceeds to S1511.

  In S1510, the current focus signal level is held as processing when the focus lens 105 is on the infinity side. The focus signal here is based on an image signal generated from the charge accumulated in the image sensor 106 when the focus lens 105 is on the close side in S1502.

  In S1511, a vibration amplitude and a center movement amplitude for driving the focus lens 105 in S1515 described later are calculated. Usually, these amplitudes are set within the depth of focus. In S1512, the focus signal level on the near side held in S1510 and the focus signal level on the infinity side held in S1502 are compared. If the former is large, the process proceeds to S1513, and if the latter is large, the process proceeds to S1514.

  In S1513, the vibration amplitude and the center movement amplitude are added to obtain a drive amplitude. In S1514, the vibration amplitude is set as the drive amplitude. In S1515, based on the drive amplitude calculated | required by S1513 or S1514, it drives to a close direction.

  In S1516, it is determined whether or not the current direction determination mode is selected. If so, the process proceeds to S1517, and if not, the process proceeds to S1522. In S1517, it is determined whether the current TV-AF control mode is the stability priority mode or the normal mode, and if it is the stability priority mode, the process proceeds to S1518, and if it is the normal mode, the process proceeds to S1519.

  In S1518, TH1 is set as the center movement frequency threshold value in the stability priority mode. In S1519, TH2 is set as the center movement frequency threshold in the normal mode. TH2 is smaller than TH1.

  In S1520, it is determined whether the number of continuous center movements in the same direction is larger than the threshold value set in S1518 or S1519. If so, the process proceeds to S1521, and if not (the threshold value or less), the process proceeds to S1524. To do. In S1521, it is determined that the direction can be determined.

  In S1522, it is determined whether the focus lens reciprocates a predetermined number of times in the same area. If so, the process proceeds to S1523, and if not, the process proceeds to S1524. In S1523, it is determined that the in-focus state has been determined. In S1524, if the counter indicating the operation state of minute driving is 3, the counter is reset to 0, and if it is any other value, the counter is added.

  The most characteristic part of the present embodiment is that the TV-AF control mode is changed according to the current shooting mode and focus state in S1401 to S1402 and S1408 to S1409, and further the TV-AF control is performed in S1517 to S1519. The threshold value of the number of continuous center movements in the same direction necessary for direction determination is changed depending on whether the mode is the stability priority mode or the normal mode. As a result, the transition to the hill-climbing drive mode is restricted once the in-focus determination has been made.Therefore, even during shooting under low illuminance, malfunction due to the influence of noise components in the focus signal is reduced, and stable focus adjustment operation is achieved. Can be obtained.

  In FIG. 16, in S1601, the drive speed of the focus lens 105 is set. In S1602, it is determined whether the current focus signal level has increased from the previous time. If so, the process proceeds to S1603, and if not, the process proceeds to S1604. In S1603, based on the speed set in S1601, the focus lens 105 is driven to climb in the same direction as the previous time.

  In S1604, it is determined whether or not the focus signal level has decreased beyond the peak. If so, the process proceeds to S1605, and if not, the process proceeds to S1606. In step S1605, it is determined that the peak position has been found. In S1606, based on the speed set in S1601, the focus lens 105 is hill-climbed in the direction opposite to the previous time. In addition, when this S1606 is repeated in the hill-climbing drive mode, it means that the focus lens 105 is in the hunting state because a sufficient amount of change in the focus signal of the subject cannot be obtained.

  Thus, in the focus adjustment control by the TV-AF method, the focus signal is always maximized by moving the focus lens 105 while repeating restart determination → micro drive → mountain climbing drive → stop → micro drive → restart determination. The in-focus state is maintained as follows.

(Fifth embodiment)
Subsequently, a fifth embodiment of the present invention will be described. FIGS. 14 and 17 are drawings that best represent the main points of the present embodiment, and the feature thereof is that the TV-AF is controlled according to the current shooting mode and in-focus state, as in the first embodiment. The mode is changed, and further, the control characteristics of the TV-AF are changed depending on whether the control mode is the stability priority mode or the normal mode. After the focus is determined once in the infrared light shooting mode, it is difficult to shift to the hill-climbing drive mode by changing the threshold of the number of center movements in the first embodiment. However, in this embodiment, the focus signal level is predetermined. A state transition that forcibly shifts to the hill-climbing drive mode when it is equal to or less than the value is provided. And it is made difficult to change to the hill-climbing drive mode by changing the minimum focus signal threshold.

  A block diagram showing a system configuration of the imaging apparatus is FIG. 1 as in the fourth embodiment. In FIG. 17, in S1901, it is determined whether the current TV-AF control mode is the stability priority mode or the normal mode. If it is the stability priority mode, the process proceeds to S1902. If it is the normal mode, the process proceeds to S1903. Transition.

  In S1902, TH3 is set as the lowest focus signal threshold value in the stability priority mode. In S1903, TH4 is set as the lowest focus signal threshold value in the normal mode. TH4 is larger than TH3. In S1904, it is determined whether the current focus signal level is greater than the threshold set in S1902 or S1903. If so, the process proceeds to S1905, and if not, the process proceeds to S1906.

  In step S1905, as a process in the case where the current focus signal level is low and it is difficult to determine the direction by normal center movement, it is assumed that the direction can be determined, and the mountain is forcibly driven in a predetermined direction from the next time. In S1906, it is determined whether the counter indicating the operation state of minute driving is currently 0. If so, the process proceeds to S1907, and if not, the process proceeds to S1908.

  In step S1907, the current focus signal level is held as processing when the focus lens 105 is on the close side. The focus signal here is based on an image signal generated from the charge accumulated in the image sensor 106 when the focus lens 105 is on the infinity side in S1915 described later.

  In S1908, it is determined whether or not the current counter is 1. If yes, the process proceeds to S1909, and if not, the process proceeds to S1914. In S1909, the vibration amplitude and the center movement amplitude for driving the focus lens 105 are calculated in S1913 described later. Usually, these amplitudes are set within the depth of focus. In S1910, the focus signal level on the infinity side held in S1907 is compared with the focus signal level on the near side held in S1915, which will be described later. If the former is large, the process proceeds to S1911. If the latter is large, the process proceeds to S1912.

  In S1911, the vibration amplitude and the center movement amplitude are added to obtain a drive amplitude. In S1912, the vibration amplitude is set as the drive amplitude. In S1913, based on the drive amplitude obtained in S1911 or S1912, the lens is driven in the direction of infinity (the movable range of the focus lens is larger).

  In S1914, it is determined whether the current counter is 2. If so, the process proceeds to S1915, and if not, the process proceeds to S1916. In S1915, the current focus signal level is held as processing when the focus lens 105 is on the infinity side. The focus signal here is based on the image signal generated from the charge accumulated in the image sensor 106 when the focus lens 105 is on the close side in S1907.

  In S1916, a vibration amplitude and a center movement amplitude for driving the focus lens 105 in S1920 described later are calculated. Usually, these amplitudes are set within the depth of focus. In S1917, the focus signal level on the near side held in S1915 is compared with the focus signal level on the infinity side held in S1907. If the former is large, the process proceeds to S1918, and if the latter is large, the process proceeds to S1919.

  In S1918, the vibration amplitude and the center movement amplitude are added to obtain a drive amplitude. In S1919, the vibration amplitude is set as the drive amplitude. In S1920, driving is performed in the closest direction based on the driving amplitude obtained in S1918 or S1919.

  In S1921, it is determined whether or not the current direction determination mode is selected. If so, the process proceeds to S1922, and if not, the process proceeds to S1924. In S1922, it is determined whether or not the focal point exists in the same direction for a predetermined number of times. If so, the process proceeds to S1923, and if not, the process proceeds to S1926. In S1923, it is determined that the direction can be determined.

  In S1924, it is determined whether the focus lens is reciprocating in the same area a predetermined number of times. If so, the process proceeds to S1925, and if not, the process proceeds to S1926. In S1925, it is determined that the in-focus determination has been made. In S1926, if the counter indicating the operation state of minute driving is 3, the counter is reset to 0, and if it is any other value, the counter is added.

  The most characteristic part of the present embodiment is that the TV-AF control mode is changed according to the current shooting mode and in-focus state in S1401 to S1402 and S1408 to S1409, and further the TV-AF control is performed in S1901 to S1903. The minimum focus signal threshold necessary for forcibly shifting to the hill-climbing mode is changed according to whether the mode is the stability priority mode or the normal mode. As a result, the transition to the hill-climbing drive mode is restricted once the in-focus determination has been made.Therefore, even during shooting under low illuminance, malfunction due to the influence of noise components in the focus signal is reduced, and stable focus adjustment operation is achieved. Can be obtained. Since other processes are the same as those in the fourth embodiment, description thereof is omitted.

(Sixth embodiment)
Subsequently, a sixth embodiment of the present invention will be described. FIGS. 18 and 19 are drawings that best represent the main points of the present embodiment, and the feature thereof is that in the same manner as in the fourth and fifth embodiments, the TV- The control mode of the AF is changed, and the control characteristic of the TV-AF is changed according to whether the control mode is the stability priority mode or the normal mode. After focusing is determined once in the infrared light shooting mode, it is difficult to shift to the hill-climbing drive mode in the fourth and fifth embodiments, but in this embodiment, it is more stable by making it difficult to perform the restart determination. The focus adjustment operation can be obtained.

  A block diagram showing a system configuration of the imaging apparatus is FIG. 1 as in the fourth embodiment. In FIG. 18, in S2001, it is determined whether the currently set photographing mode is the infrared light photographing mode or the visible light photographing mode. If the photographing mode is the visible light photographing mode, the process proceeds to S2002. If it is, the process proceeds to S2003.

  In S2002, the control mode of the TV-AF control is set to the normal mode as processing in the visible light photographing mode. In S2003, it is determined whether or not the mode is the micro drive mode. If the mode is the micro drive mode, the process proceeds to S2004, and if not, the process proceeds to S2012.

  In S2004, a minute driving operation is performed, the focus lens is driven with a predetermined amplitude, and it is determined whether it is in focus or in which direction the focus is present. The detailed operation here will be described with reference to FIG.

  In S2005, it is determined whether or not the focus determination has been performed by the minute drive operation in S2004. If the focus determination is performed by the minute drive operation, the process proceeds to S2008, and if not, the process proceeds to S2006. In S2006, it is determined whether or not the direction can be determined by the minute drive operation in S2004. If the direction can be determined, the process proceeds to S2007 and the hill-climbing operation is performed. If not, the process returns to S2001 and the minute drive mode is continued. To do.

  In S2008, it is determined again whether the currently set shooting mode is the infrared light shooting mode or the visible light shooting mode. If it is the infrared light shooting mode, the process proceeds to S2009. Transits to S2010. In S2009, as a process when the in-focus determination can be performed in the infrared light shooting mode, the control mode of the TV-AF control is set to the stability priority mode in order to stabilize the subsequent focus adjustment operation.

  In the present embodiment, the stability priority mode is set when the focus can be determined in the infrared light shooting mode. However, the stability priority mode is set after a lapse of a predetermined time after shifting to the infrared light shooting mode. It does not matter as a setting.

  In S2010, the focus signal level at the time of focusing is stored in the memory, and then the process proceeds to S2011 to shift to the restart determination mode. Here, the restart determination mode is a flow for determining whether or not minute driving (direction determination) is performed again (S2023, S2024).

  In S2012, it is determined whether or not the hill-climbing drive mode is selected. If the hill-climbing drive mode is selected, the process proceeds to S2013, and if not, the process proceeds to S2017. In S2013, a hill-climbing driving operation is performed, and the focus lens is hill-climbed and driven at a predetermined speed in a direction in which the focus signal increases. The detailed operation here is the same as that of the fourth embodiment, and will be omitted.

  In S2014, it is determined whether or not the peak position of the focus signal has been found by the hill-climbing drive operation in S2013. If the peak position of the focus signal is found, the process proceeds to S2015, and if not, the process returns to S2001 and the hill-climbing drive mode. Continue. If it is determined in S2014 that the peak position has been found, the focus determination mode is set after the focus lens is moved to the peak position (S2019).

  In S2015, after setting the focus lens position at which the focus signal reaches a peak as the target position, the process proceeds to S2016, and the process proceeds to the stop mode. In S2017, it is determined whether the mode is the stop mode. If the mode is the stop mode, the process proceeds to S2018. If not, the process proceeds to S2020.

  In S2018, it is determined whether or not the focus lens has returned to the position where the focus signal reaches the peak. If so, the process proceeds to S2019 to shift to the minute drive (focus determination) mode, and otherwise to S2001. Continue return stop mode.

  In S2020, it is determined whether the control mode of the current TV-AF control is the stability priority mode or the normal mode. If it is the stability priority mode, the process proceeds to S2021, and if it is the normal mode, the process proceeds to S2022. In S2021, TH5 is set as the focus signal fluctuation amount threshold value in the stability priority mode. In S2022, TH6 is set as the focus signal fluctuation amount threshold value in the normal mode. TH6 is smaller than TH5.

  In S2023, the current focus signal level is compared with the focus signal level held in S2010, and it is determined whether or not the fluctuation amount is larger than the threshold set in S2021 or S2022. If it is determined that the amount of variation is large, the process proceeds to S2024 to shift to the minute drive (direction determination) mode. If not, the process returns to S2001 and the restart determination mode is continued.

  In FIG. 19, in S <b> 2101, it is determined whether or not the counter indicating the operation state of minute driving is currently 0. If so, the process proceeds to S <b> 2102, and if not, the process proceeds to S <b> 2103. In S2102, the current focus signal level is held as a process when the focus lens 105 is on the close side. The focus signal here is based on an image signal generated from the charge accumulated in the image sensor 106 when the focus lens 105 is on the infinity side in S2110 described later.

  In S2103, it is determined whether or not the current counter is 1. If so, the process proceeds to S2104, and if not, the process proceeds to S2109. In S2104, the vibration amplitude and the center movement amplitude for driving the focus lens 105 are calculated in S2108 described later. Usually, these amplitudes are set within the depth of focus.

  In S2105, the focus signal level on the infinity side held in S2102 is compared with the focus signal level on the near side held in S2110, which will be described later. If the former is large, the process proceeds to S2106, and if the latter is large, the process proceeds to S2107. In S2106, the vibration amplitude and the center movement amplitude are added to obtain a drive amplitude. In S2107, the vibration amplitude is set as the drive amplitude.

  In S2108, based on the driving amplitude obtained in S2106 or S2107, driving is performed in the infinity direction. In S2109, it is determined whether or not the current counter is 2. If so, the process proceeds to S2110, and if not, the process proceeds to S2111.

  In S2110, the current focus signal level is held as processing when the focus lens 105 is on the infinity side. The focus signal here is based on an image signal generated from charges accumulated in the image sensor 106 when the focus lens 105 is on the close side in S2102.

  In S2111, a vibration amplitude and a center movement amplitude for driving the focus lens 105 in S2115 described later are calculated. Usually, these amplitudes are set within the depth of focus. In S2112, the focus signal level on the near side held in S2110 is compared with the focus signal level on the infinity side held in S2102. If the former is large, the process proceeds to S2113, and if the latter is large, the process proceeds to S2114.

  In S2113, the vibration amplitude and the center movement amplitude are added to obtain a drive amplitude. In S2114, the vibration amplitude is set as the drive amplitude. In S2115, based on the drive amplitude obtained in S2113 or S2114, driving is performed in the closest direction.

  In S2116, it is determined whether or not the current direction determination mode is selected. If so, the process proceeds to S2117, and if not, the process proceeds to S2122. In S2117, it is determined whether or not the focal point exists in the same direction for a predetermined number of times. If so, the process proceeds to S2118, and if not, the process proceeds to S2121. In S2118, it is determined that the direction has been determined.

  In S2119, it is determined whether or not the focus lens has reciprocated in the same area a predetermined number of times. If so, the process proceeds to S2120, and if not, the process proceeds to S2121. In S2120, it is determined that the in-focus determination has been made. In S2121, if the counter indicating the operation state of minute driving is 3, the counter is reset to 0, and if it is any other value, the counter is added.

  The most characteristic part of the present embodiment is that the control mode of TV-AF is changed according to the current shooting mode and focus state in S2001 to S2002 and S2008 to S2009, and further, the control of TV-AF is controlled in S2020 to S2022. The threshold value of the focus signal fluctuation amount necessary for restart determination is changed depending on whether the mode is the stability priority mode or the normal mode.

  As a result, once the focus is determined, restart of the TV-AF operation is limited. Therefore, even when shooting under low illuminance, malfunction caused by the noise component of the focus signal is reduced, and more stable focus adjustment is possible. An operation can be obtained. Since other processes are the same as those in the fourth embodiment, description thereof is omitted.

(Seventh embodiment)
Subsequently, a seventh embodiment of the present invention will be described. FIGS. 14 and 20 are drawings that best represent the main points of the present embodiment, and the feature thereof is the same as in the fourth, fifth, and sixth embodiments in accordance with the current shooting mode and in-focus state. Thus, the control mode of the TV-AF is changed, and the control characteristics of the TV-AF are changed according to whether the control mode is the stability priority mode or the normal mode. After the focus is determined once in the infrared light shooting mode, it is difficult to shift to the hill-climbing drive mode in the fourth and fifth embodiments, and the restart determination is difficult to perform in the sixth embodiment. However, in this embodiment, it is possible to obtain a more stable focus adjustment operation by facilitating the focus discrimination itself.

  A block diagram showing a system configuration of the imaging apparatus is FIG. 1 as in the fourth and fifth embodiments. In FIG. 20, in S2201, it is determined whether the counter indicating the operation state of minute driving is currently 0. If so, the process proceeds to S2202, and if not, the process proceeds to S2203.

  In step S2202, the current focus signal level is held as processing when the focus lens 105 is on the close side. The focus signal here is based on an image signal generated from charges accumulated in the image sensor 106 when the focus lens 105 is on the infinity side in S2210 described later.

  In S2203, it is determined whether or not the current counter is 1. If so, the process proceeds to S2204, and if not, the process proceeds to S2209. In S2204, a vibration amplitude and a center movement amplitude for driving the focus lens 105 in S2208 described later are calculated. Usually, these amplitudes are set within the depth of focus.

  In S2205, the focus signal level on the infinity side held in S2202 is compared with the focus signal level on the near side held in S2210, which will be described later. If the former is large, the process proceeds to S2206, and if the latter is large, the process proceeds to S2207. In S2206, the vibration amplitude and the center movement amplitude are added to obtain a drive amplitude. In S2207, the vibration amplitude is set as the drive amplitude.

  In S2208, based on the drive amplitude obtained in S2206 or S2207, driving is performed in the infinity direction. In S2209, it is determined whether or not the current counter is 2. If so, the process proceeds to S2210, and if not, the process proceeds to S2211.

  In S2210, the current focus signal level is held as processing when the focus lens 105 is on the infinity side. The focus signal here is based on an image signal generated from charges accumulated in the image sensor 106 when the focus lens 105 is on the close side in S2202.

  In S2211, the vibration amplitude and the center movement amplitude for driving the focus lens 105 in S2215 described later are calculated. Usually, these amplitudes are set within the depth of focus. In S2212, the focus signal level on the near side held in S2210 and the focus signal level on the infinity side held in S2202 are compared. If the former is large, the process proceeds to S2213, and if the latter is large, the process proceeds to S2214.

  In S2213, the vibration amplitude and the center movement amplitude are added to obtain a drive amplitude. In S2214, the vibration amplitude is set as the drive amplitude. In S2215, driving is performed in the closest direction based on the driving amplitude obtained in S2213 or S2214.

  In S2216, it is determined whether or not the current direction determination mode is selected. If so, the process proceeds to S2217, and if not, the process proceeds to S2219. In S2217, it is determined whether a focal point exists in the same direction continuously for a predetermined number of times. If so, the process proceeds to S2218, and if not, the process proceeds to S2224. In S2218, it is determined that the direction has been determined.

  In S2219, it is determined whether the control mode of the current TV-AF control is the stability priority mode or the normal mode. If it is the stability priority mode, the process proceeds to S2220, and if it is the normal mode, the process proceeds to S2221.

  In S2220, TH7 is set as the round-trip count threshold in the stability priority mode. In S2221, TH8 is set as the round-trip frequency threshold in the normal mode. TH8 is larger than TH7. In S2222, it is determined whether or not the current reciprocation count (inversion count) of the focus lens 105 is larger than the threshold set in S2220 or S2221. If so, the process proceeds to S2223, and if not, the process proceeds to S2224. In S2223, it is determined that the in-focus determination has been made. In S2224, if the counter indicating the operation state of minute driving is 3, the counter is reset to 0, and if it is any other value, the counter is added.

  The most characteristic part of the present embodiment is that the control mode of the TV-AF is changed in S1406 to S1408 depending on whether the current shooting mode is the infrared light shooting mode or the visible light shooting mode, and further S2217. In S2219, the same-area reciprocation frequency threshold value of the focus lens 105 necessary for focusing determination is changed according to whether the control mode of the TV-AF is the stability priority mode or the normal mode.

  As a result, the time required for focusing determination is shortened, so that malfunctions due to the influence of noise components of the focus signal can be reduced even during shooting under low illuminance, and a more stable focus adjustment operation can be obtained. Since other processes are the same as those in the fourth, fifth, and sixth embodiments, description thereof is omitted.

(Eighth embodiment)
Subsequently, an eighth embodiment of the present invention will be described. As in the fourth to seventh embodiments, the feature of this embodiment is that the TV-AF control mode is changed according to the current shooting mode and focus state, and the control mode is stable. The control characteristic of the TV-AF is changed depending on whether the mode is the priority mode or the normal mode. In the fourth to seventh embodiments, the focus adjustment is always performed using the latest focus signal in each control step. However, in this embodiment, for example, the average value of the focus signals for the three most recent fields is used. Thus, the focus signal itself is used after being smoothed. As a result, the influence of noise is reduced, and a stable focus adjustment operation can be obtained. The detailed description is the same as that of the fourth to seventh embodiments, and will be omitted.

(Ninth embodiment)
Subsequently, a ninth embodiment of the present invention will be described. As in the fourth to seventh embodiments, the feature of this embodiment is that the TV-AF control mode is changed according to the current shooting mode and focus state, and the control mode is stable. The control characteristic of the TV-AF is changed depending on whether the mode is the priority mode or the normal mode. In the fourth to seventh embodiments, for example, the magnitude relationship between the fluctuation amount of the focus signal and the threshold value is directly compared at the time of restart determination. However, in this embodiment, this fluctuation amount is given a hysteresis α to When the difference between the fluctuation amount and the threshold value is greater than or equal to α, it is determined that the restart should be performed. As a result, the influence of noise is reduced, and a stable focus adjustment operation can be obtained. The detailed description is the same as that of the fourth to seventh embodiments, and will be omitted.

  Although the present invention has been described in detail based on preferred embodiments thereof, the present invention is not limited to these specific embodiments, and various forms within the scope of the present invention are also included in the present invention. included. A part of the above-described embodiments may be appropriately combined.

Claims (12)

An imaging optical system including a focus lens;
An image sensor for generating an image signal of an object image formed by the imaging optical system and photoelectrically converted,
An infrared light removal filter that removes an infrared light component contained in the light incident on the image sensor;
Filter driving means for taking the infrared light removal filter into and out of the optical path of the imaging optical system;
A focus signal detection means for extracting a high-frequency component of an imaging signal obtained from the imaging element as a focus signal;
The focus lens is searched for the in-focus direction by reciprocatingly driving the focus lens, the focus lens is continuously moved in the in-focus direction, and the focus lens is driven to adjust the focus so that the focus signal reaches a peak. Focusing means for performing ,
The focus adjusting unit is configured such that when the infrared light removal filter is taken in and out of the optical path of the imaging optical system by the filter driving unit, the infrared light removal filter stored in advance in the storage unit is the imaging optical. An imaging apparatus , wherein a focus position is searched by continuously moving the focus lens in a predetermined direction based on a shift direction of an in-focus position when being taken in and out of an optical path of the system. Setting means for setting an offset amount for moving the focus lens when the infrared light removal filter is put in and out of the optical path of the imaging optical system by the filter driving means;
The focus adjustment unit moves the focus lens based on the offset amount set by the setting unit when the infrared light removal filter is put in and out of the optical path of the imaging optical system by the filter driving unit. Then, the focus lens is continuously moved in a predetermined direction on the basis of the shift direction of the in-focus position when the infrared light removal filter stored in advance in the storage means is put in and out of the optical path of the imaging optical system. The imaging apparatus according to claim 1, wherein the imaging device is moved to search for a focal position. Said focusing means, the pre-Symbol focus lens is moved continuously in a predetermined direction the driving speed of the focus lens when searching for a focal position, the infrared light removal filter on an optical path of the imaging optical system the imaging apparatus according to claim 1 or 2, characterized that you larger than when not out. An imaging optical system including a focus lens;
An imaging element that photoelectrically converts an object image formed by the imaging optical system to generate an imaging signal;
An infrared light removal filter that removes an infrared light component contained in the light incident on the image sensor;
Filter driving means for taking the infrared light removal filter into and out of the optical path of the imaging optical system;
A focus signal detection means for extracting a high-frequency component of an imaging signal obtained from the imaging element as a focus signal;
The focus lens is searched for the in-focus direction by reciprocatingly driving the focus lens, the focus lens is continuously moved in the in-focus direction, and the focus lens is driven to adjust the focus so that the focus signal reaches a peak. Focusing means for performing,
Said focusing means, by the filter drive means, when said infrared light removal filter is out on an optical path of the imaging optical system, when searching the focus direction by causing the focus lens round trip driven the movement amount of the focus lens, the infrared light removal filter imaging device characterized that you larger than when not out on an optical path of the imaging optical system. An imaging optical system including a focus lens;
An image sensor for generating an image signal of an object image formed by the imaging optical system and photoelectrically converted,
An infrared light removal filter that removes an infrared light component contained in the light incident on the image sensor;
Filter driving means for taking the infrared light removal filter into and out of the optical path of the imaging optical system;
A focus signal detection means for extracting a high-frequency component of an imaging signal obtained from the imaging element as a focus signal;
And a focus adjustment unit that performs focus adjustment by driving the focus lens such that the focus signal becomes a peak,
The focus adjustment unit has a hill-climbing drive mode in which the focus lens is continuously moved in a predetermined direction to search for a focus position, and a minute drive mode in which the focus lens is searched for by reciprocating the focus lens. When the number of movements in the same direction of the center position of the reciprocating drive of the focus lens in the minute driving mode is larger than a threshold value, the moving direction of the center position is changed to the hill-climbing driving mode as the driving direction of the focus lens. The infrared light removal filter is inserted into the optical path of the imaging optical system in the visible light photographing mode, and the infrared light removal filter is retracted from the optical path of the imaging optical system for photographing. in the case of infrared light imaging mode to perform, toward the case of the infrared light imaging mode, characterized in that to increase the threshold Image apparatus. An imaging optical system including a focus lens;
An imaging element that photoelectrically converts an object image formed by the imaging optical system to generate an imaging signal;
An infrared light removal filter that removes an infrared light component contained in the light incident on the image sensor;
Filter driving means for taking the infrared light removal filter into and out of the optical path of the imaging optical system;
A focus signal detection means for extracting a high-frequency component of an imaging signal obtained from the imaging element as a focus signal;
Focus adjusting means for adjusting the focus by driving the focus lens so that the focus signal reaches a peak;
It said focusing means, chromatic and climbing drive mode to search for a focal position is moved continuously the focus lens in a predetermined direction, and a fine drive mode to search for a focal position by causing the focus lens round trip driven and, wherein when the value of the focus signal threshold below in the fine drive mode, the shifts Previous Symbol climbing drive mode, performs photographing by inserting the infrared removing filter on an optical path of the imaging optical system In the case of the visible light photographing mode and in the case of the infrared light photographing mode in which photographing is performed by retracting the infrared light removal filter from the optical path of the imaging optical system, the case of the infrared light photographing mode is better. , imaging device, characterized in that to reduce the threshold. An imaging optical system including a focus lens;
An imaging element that photoelectrically converts an object image formed by the imaging optical system to generate an imaging signal;
An infrared light removal filter that removes an infrared light component contained in the light incident on the image sensor;
Filter driving means for taking the infrared light removal filter into and out of the optical path of the imaging optical system;
A focus signal detection means for extracting a high-frequency component of an imaging signal obtained from the imaging element as a focus signal;
Focus adjusting means for adjusting the focus by driving the focus lens so that the focus signal reaches a peak;
Said focusing means, said has a fine drive mode to search for a focal position by causing the focus lens reciprocations driven, and a stop mode in which the focus lens is stopped, the variation of the focus signal in the stop mode When the amount is larger than the threshold value, the mode is shifted to the minute driving mode, and the infrared light removing filter is inserted in the optical path of the imaging optical system to perform imaging, and the infrared light in the case the filter for removing infrared light imaging mode for imaging is retracted from the optical path of the imaging optical system, toward the case of the infrared light imaging mode, characterized that you increase the threshold imaging device. An imaging optical system including a focus lens, an imaging element that photoelectrically converts an object image formed by the imaging optical system to generate an imaging signal, and an infrared light component included in light incident on the imaging element is removed A method of controlling an imaging apparatus comprising: an infrared light removing filter; and a filter driving means for taking the infrared light removing filter into and out of an optical path of the imaging optical system,
A focus signal detection step of extracting a high-frequency component of an image pickup signal obtained from the image pickup device as a focus signal;
The focus lens is searched for the in-focus direction by reciprocatingly driving the focus lens, the focus lens is continuously moved in the in-focus direction, and the focus lens is driven to adjust the focus so that the focus signal reaches a peak. A focusing step to be performed,
In the focus adjustment step, when the infrared light removal filter is put in and out of the optical path of the imaging optical system by the filter driving means, the infrared light removal filter stored in advance in the storage means is used as the imaging optical. A control method for an image pickup apparatus, wherein a focus position is searched by continuously moving the focus lens in a predetermined direction based on a shift direction of an in-focus position when the lens is taken in and out of the optical path of the system. An imaging optical system including a focus lens, an imaging element that photoelectrically converts an object image formed by the imaging optical system to generate an imaging signal, and an infrared light component included in light incident on the imaging element is removed A method of controlling an imaging apparatus comprising: an infrared light removing filter; and a filter driving means for taking the infrared light removing filter into and out of an optical path of the imaging optical system,
A focus signal detection step of extracting a high-frequency component of an image pickup signal obtained from the image pickup device as a focus signal;
The focus lens is searched for the in-focus direction by reciprocatingly driving the focus lens, the focus lens is continuously moved in the in-focus direction, and the focus lens is driven to adjust the focus so that the focus signal reaches a peak. A focusing step to be performed,
In the focus adjustment step, when the infrared light removal filter is put in and out of the optical path of the imaging optical system by the filter driving unit, the focus lens is reciprocated to search for the in-focus direction. A method for controlling an imaging apparatus, wherein the amount of movement of the focus lens is made larger than when the infrared light removal filter is not taken in and out of the optical path of the imaging optical system. An imaging optical system including a focus lens, an imaging element that photoelectrically converts an object image formed by the imaging optical system to generate an imaging signal, and an infrared light component included in light incident on the imaging element is removed A method of controlling an imaging apparatus comprising: an infrared light removing filter; and a filter driving means for taking the infrared light removing filter into and out of an optical path of the imaging optical system,
A focus signal detection step of extracting a high-frequency component of an image pickup signal obtained from the image pickup device as a focus signal;
A focus adjustment step of adjusting the focus by driving the focus lens so that the focus signal reaches a peak,
The focus adjustment step includes a hill-climbing drive mode in which the focus lens is continuously moved in a predetermined direction to search for a focus position, and a minute drive mode in which the focus lens is searched for by reciprocating the focus lens. When the number of movements in the same direction of the center position of the reciprocating drive of the focus lens in the minute driving mode is larger than a threshold value, the moving direction of the center position is changed to the hill-climbing driving mode as the driving direction of the focus lens. The infrared light removal filter is inserted into the optical path of the imaging optical system in the visible light photographing mode, and the infrared light removal filter is retracted from the optical path of the imaging optical system for photographing. In the case of the infrared light photographing mode to be performed, the threshold value is increased in the case of the infrared light photographing mode. Control method for an image device. An imaging optical system including a focus lens, an imaging element that photoelectrically converts an object image formed by the imaging optical system to generate an imaging signal, and an infrared light component included in light incident on the imaging element is removed A method of controlling an imaging apparatus comprising: an infrared light removing filter; and a filter driving means for taking the infrared light removing filter into and out of an optical path of the imaging optical system,
A focus signal detection step of extracting a high-frequency component of an image pickup signal obtained from the image pickup device as a focus signal;
A focus adjustment step of adjusting the focus by driving the focus lens so that the focus signal reaches a peak,
The focus adjustment step includes a hill-climbing drive mode in which the focus lens is continuously moved in a predetermined direction to search for a focus position, and a minute drive mode in which the focus lens is searched for by reciprocating the focus lens. When the value of the focus signal in the minute driving mode is equal to or less than a threshold value, the visible light is used for shooting by shifting to the hill-climbing driving mode and inserting the infrared light removal filter on the optical path of the imaging optical system. In the case of the photographing mode, and in the case of the infrared light photographing mode in which the infrared light removal filter is retracted from the optical path of the imaging optical system for photographing, the infrared light photographing mode is more A control method for an imaging apparatus, characterized by reducing a threshold value. An imaging optical system including a focus lens, an imaging element that photoelectrically converts an object image formed by the imaging optical system to generate an imaging signal, and an infrared light component included in light incident on the imaging element is removed A method of controlling an imaging apparatus comprising: an infrared light removing filter; and a filter driving means for taking the infrared light removing filter into and out of an optical path of the imaging optical system,
A focus signal detection step of extracting a high-frequency component of an image pickup signal obtained from the image pickup device as a focus signal;
A focus adjustment step of adjusting the focus by driving the focus lens so that the focus signal reaches a peak,
The focus adjustment step has a micro drive mode for searching for a focus position by reciprocatingly driving the focus lens, and a stop mode in which the focus lens is stopped, and a variation amount of the focus signal in the stop mode. In the case of visible light photographing mode in which the transition to the minute driving mode is performed and the infrared light removal filter is inserted in the optical path of the imaging optical system, and the infrared light removal is performed. An imaging apparatus characterized in that the threshold value is larger in the infrared light imaging mode than in the infrared light imaging mode in which the filter is retracted from the optical path of the imaging optical system. Control method.

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