Imaging device

Abstract

To provide an imaging device capable of keep focusing on a subject even if the subject moves fast.SOLUTION: An imaging device includes: a distance measuring device having a light emitting part for emitting light, a light reception part for receiving light which is emitted by the light emitting part and then reflected by a subject, and a generation part for generating information regarding a distance to the subject based on a light reception result by the light reception part; an imaging element for outputting a signal by receiving light passed through an optical system having a focus lens; and a control part for controlling the distance measuring device and the imaging element.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This relates to an imaging device. [Background technology]

[0002] BACKGROUND ART There has been proposed an imaging device that performs focus control by adjusting the position of a focus lens based on a distance measured by a TOF sensor that measures the distance to an object (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-32990 Summary of the Invention

[0004] According to one aspect of the disclosure, the imaging device comprises a distance measuring device having an emitting unit that emits light, a light receiving unit that receives light that is reflected by an object from the light emitting unit, and a generation unit that generates information regarding the distance to the object based on the light reception result of the light receiving unit, an imaging element that receives light that has passed through an optical system having a focus lens and outputs a signal, and a control unit that controls the distance measuring device and the imaging element.

[0005] The configurations of the embodiments described below may be modified as appropriate, and at least a portion of the configuration may be replaced with other components. Furthermore, components that are not particularly limited in terms of their placement may be placed in any position that can achieve their function, not limited to the placement disclosed in the embodiments. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a diagram showing the configuration of a camera according to the first embodiment. [Figure 2] 2(a) and 2(b) are flowcharts showing an example of processing executed by the body control unit of the camera body in the first embodiment. [Figure 3] Figure 3 is a timing chart showing the processing timings of the camera body and the distance measuring device in the first embodiment. [Figure 4] Figure 4 is a flowchart showing the flow of processing by the body control unit in the second embodiment. [Figure 5] Figure 5(a) is a timing chart showing the processing timings of the camera body and the distance measuring device in the second embodiment, and Figure 5(b) is a diagram showing a comparative example. [Figure 6] Figure 6 is a flowchart showing the drive control of the focus lens by the body control unit in the third embodiment. [Figure 7] Figure 7(a) is a timing chart showing the processing timings of the camera body and the distance measuring device in the third embodiment, and Figure 7(b) is a diagram showing a comparative example. [Figure 8] Figure 8 is a timing chart showing the processing timings of the camera body and the distance measuring device in the fourth embodiment. [Figure 9] Figure 9 is a flowchart showing the processing executed by the body control unit before performing the drive amount calculation of the focus lens using the result of the distance measurement processing in the fourth embodiment. [Figure 10] Figure 10 is a diagram showing an overview of the fourth embodiment. [Figure 11] Figure 11 is a diagram showing an overview of Modification Example 1 of the fourth embodiment. [Figure 12] Figure 12 is a diagram showing an overview of Modification Example 2 of the fourth embodiment. [Figure 13] Figure 13 is a flowchart showing the processing executed by the body control unit before performing the drive amount calculation of the focus lens using the result of the distance measurement processing in Modification Example 2 of the fourth embodiment. [Figure 14] Figure 14 is a diagram showing an overview of the processing in the fifth embodiment. [Figure 15] Figure 15 is a diagram showing an overview of the processing in a modification of the fifth embodiment.

Mode for Carrying Out the Invention

[0007] First Embodiment A digital camera 1 (hereinafter referred to as camera 1), which is an example of an imaging device according to a first embodiment, will be described below with reference to FIGS.

[0008] 1 is a diagram showing the configuration of a camera 1 according to the first embodiment. The camera 1 includes a camera body 2, an interchangeable lens 3, and a distance measuring device 50.

[0009] (Risting device 50) The distance measuring device 50 is, for example, a distance measuring device that uses LiDAR (Light Detection And Ranging) to irradiate a laser beam and measure the distance to an object and the shape and size of the object based on information on the reflected light. The distance measuring device 50 includes a light emitting unit 501, a light receiving unit 502, a control unit 503, and a distance measuring device side connector unit 504.

[0010] The light emitting unit 501 is, for example, a VCSEL (vertical cavity surface emitting laser), and emits laser light such as near-infrared light toward a target area. Here, the target area is an area corresponding to the imaging range of the distance measuring device 50, and is an area according to the angle of view of the distance measuring device 50.

[0011] The light receiving unit 502 detects light from the target area. Specifically, the light receiving unit 502 is an imaging element that detects light emitted from the light emitting unit 501 and reflected by an object (target) within the target area. The light receiving unit 502 includes a light receiving pixel unit 502a and a light receiving pixel control unit 502b. In the following description, light reflected by an object within the target area may be referred to as reflected light.

[0012] The light-receiving pixel unit 502a has a plurality of pixels, each having a photoelectric conversion unit. The plurality of pixels are arranged two-dimensionally (in the row and column directions). The photoelectric conversion units are configured by photodiodes (PDs) or more sensitive single photon avalanche diodes (SPADs).

[0013] The photoelectric conversion unit of each pixel of the light-receiving pixel unit 502a receives reflected light emitted by the light-emitting unit 501 and accumulates electric charges corresponding to the amount of reflected light. More specifically, the photoelectric conversion unit of each pixel accumulates electric charges corresponding to the amount of reflected light received within a predetermined exposure time. Then, the light-receiving pixel unit 502a outputs a signal corresponding to the electric charges accumulated in the photoelectric conversion unit from each pixel to the control unit 503 in accordance with a control signal from the light-receiving pixel control unit 502b.

[0014] The light-receiving pixel control unit 502b causes each pixel of the light-receiving pixel unit 502a to accumulate charge based on an instruction signal from the control unit 503, and causes each pixel to output a signal based on the accumulated charge.

[0015] Using signals output from each pixel of the light-receiving pixel section 502a, the control section 503 calculates the time Δt from when the light-emitting section 501 emits light until the reflected light of the emitted light is received by the light-receiving section 502, and calculates the distance to each object in the target area based on the time Δt and the speed of light. That is, the control section 503 includes a generation section 505 that calculates the distance to the object for each pixel of the light-receiving pixel section 502a and generates an image in which the pixel value is (a value corresponding to) that distance, and an image in which the pixel value is information based on the intensity of the reflected light (hereinafter, these will be collectively referred to as a distance image).

[0016] The control unit 503 transmits (transfers) the generated distance image to the body control unit 21 via the ranging-device-side connector unit 504 and the body-side connector unit 26, which will be described later. In the first embodiment, the ranging device 50 is detachable from the camera body 2. When the ranging device 50 is attached to the camera body 2, communication between the ranging device 50 and the camera body 2 becomes possible via the ranging-device-side connector unit 504 and the body-side connector unit 26.

[0017] (Interchangeable Lens 3) The interchangeable lens 3 includes a lens-side mount portion 301, a photographing optical system (imaging optical system) 31, a lens control unit 32, and a lens memory 33. The lens-side mount portion 301 includes a lens-side connection portion 302. The lens-side connection portion 302 has a plurality of terminals such as a terminal for a clock signal, a terminal for a data signal, and a terminal for power supply. The interchangeable lens 3 is detachably attached to the camera body 2 by the lens-side mount portion 301 and a body-side mount portion 201 described later.

[0018] The photographing optical system 31 includes a plurality of lenses having a zoom lens (variable magnification lens) 31a for changing the focal length and a focus lens (focus adjustment lens) 31b, and a diaphragm 31c, and forms an image of an object on the imaging surface 22a of the imaging device 22.

[0019] The lens control unit 32 is composed of a processor such as a CPU (Central Processing Unit), an FPGA (Field Programmable Gate Array), or an ASIC (Application Specific Integrated Circuit), and a memory such as a ROM (Read Only Memory) and a RAM (Random Access Memory), and controls each part of the interchangeable lens 3 based on a control program. The lens control unit 32 controls the position of the zoom lens 31a, the position of the focus lens 31b, and the drive of the diaphragm 31c based on a signal output from the body control unit 21 of the camera body 2. When a signal indicating the moving direction and the moving amount of the focus lens 31b is input from the body control unit 21, the lens control unit 32 moves the focus lens 31b back and forth in the direction of the optical axis OA1 based on the signal to adjust the focus position of the photographing optical system 31. Further, the lens control unit 32 controls the position of the zoom lens 31a and the aperture diameter of the diaphragm 31c based on a signal output from the body control unit 21 of the camera body 2.

[0020] The lens memory 33 is constituted by, for example, a non-volatile storage medium or the like. Information related to the interchangeable lens 3 is stored (recorded) as lens information in the lens memory 33. The lens information includes data regarding the optical characteristics (e.g., exit pupil distance and F-number) of the photographic optical system 31, data regarding the shortest shooting distance of the photographic optical system 31, and the like. Note that the lens information varies depending on the type of the interchangeable lens 3. Also, the lens information may be stored in the memory inside the lens control unit 32. Further, the lens information may be stored in the body memory 23 of the camera body 2 described later. In this case, the body memory 23 stores the lens information of a plurality of interchangeable lenses 3.

[0021] Reading of data from the lens memory 33 is controlled by the lens control unit 32. When the interchangeable lens 3 is attached to the camera body 2, the lens control unit 32 transmits the lens information to the body control unit 21 via the terminals of the lens-side connection unit 302 and the body-side connection unit 202. Also, the lens control unit 32 transmits the position information (focal length information) of the controlled zoom lens 31a, the position information of the controlled focus lens 31b, information on the aperture value (F-number) of the controlled photographic optical system 31, and the like to the body control unit 21.

[0022] The lens control unit 32 performs communication for bidirectionally transmitting and receiving information between the camera body 2 and the interchangeable lens 3 via the terminals of the lens-side connection unit 302 and the body-side connection unit 202. When the zoom lens 31a moves and the focal length of the photographic optical system 31 changes, the lens control unit 32 may transmit the information on the focal length of the photographic optical system 31 and the information on the aperture value of the photographic optical system 31 to the body control unit 21, or may periodically transmit the information on the focal length of the photographic optical system 31 and the information on the aperture value of the photographic optical system 31 to the body control unit 21.

[0023] (Camera body 2) The camera body 2 includes a body-side mount portion 201, an imaging element 22, a body memory 23, a display unit 24, an operation unit 25, a body-side connector portion 26, and a body control unit 21.

[0024] The body-side mounting portion 201 includes a body-side connection portion 202. The body-side connection portion 202 has a plurality of terminals such as a terminal for a clock signal, a terminal for a data signal, and a terminal for power supply.

[0025] When the interchangeable lens 3 is attached to the camera body 2, the terminals provided on the body-side connection portion 202 and the terminals provided on the lens-side connection portion 302 are electrically connected. Thereby, power supply from the camera body 2 to the interchangeable lens 3 and communication between the camera body 2 and the interchangeable lens 3 become possible.

[0026] The imaging element 22 is a CMOS image sensor or a CCD image sensor. The imaging element 22 images an image of an object formed by the imaging optical system 31. The imaging element 22 includes a pixel portion 221 in which a plurality of pixels having a photoelectric conversion portion are two-dimensionally (in the row direction and the column direction) arranged, and a control portion 222 that controls the pixel portion 221. The photoelectric conversion portion is constituted by a photodiode.

[0027] The pixel portion 221 has imaging pixels that photoelectrically convert the received light by the photoelectric conversion portion and output signals used for image generation, and focus detection pixels that photoelectrically convert the received light by the photoelectric conversion portion and output signals used for focus detection.

[0028] The control portion 222 causes the focus detection pixels to output signals used for focus detection based on an instruction signal from the body control portion 21. Further, the control portion 222 causes the imaging pixels to output signals used for image generation based on an instruction signal from the body control portion 21.

[0029] The body memory 23 is constituted by, for example, a non-volatile storage medium or the like. Image data, a control program, and the like are recorded in the body memory 23. Writing data to the body memory 23 and reading data from the body memory 23 are controlled by the body control portion 21.

[0030] The display unit 24 displays an image based on image data generated from signals output from the imaging pixels of the pixel unit 221 (called a "live view image"), an image based on a distance image (called an "auxiliary image"), an image showing a focus detection area (AF area) such as an AF frame, information related to shooting such as shutter speed and F-number, and a menu screen, etc.

[0031] The operation unit 25 includes various setting switches such as a release button, a power switch, and switches for switching between various modes, and outputs operation signals to the body control unit 21 according to the respective operations.

[0032] The body control unit 21 is configured with a processor such as a CPU, FPGA, or ASIC, and memories such as ROM and RAM, and controls each unit of the camera 1 based on a control program. The body control unit 21 also controls the operation and processing of the distance measuring device 50 by issuing instructions to the control unit 503 of the distance measuring device 50.

[0033] The body control unit 21 drives the focus lens 31b based on the defocus amount calculated based on the signals output from the focus detection pixels. The body control unit 21 also generates image data based on signals used for image generation output from the imaging pixels of the pixel unit 221, and stores the image data in the body memory 23 or displays it on the display unit 24 as a live view image in response to a user's operation of the operation unit 25 (release button).

[0034] Here, when the photographer performs long exposure shooting (such as panning), signals output from the imaging pixels of the pixel unit 221 are used to generate image data to be stored in the body memory 23. For this reason, during long exposure shooting, images generated based on signals output from the imaging pixels of the pixel unit 221 cannot be displayed as live view images on the display unit 24. Therefore, unless some countermeasure is taken, the live view image will not be displayed on the display unit 24 (a blackout will occur).

[0035] When performing panning shooting, the photographer needs to adjust the shooting direction so that the subject is located at the same position in the frame during shooting (for example, 1 / 30 second). Therefore, if blackout occurs during long-exposure shooting, it may be impossible or difficult to perform panning shooting because the subject cannot be tracked while viewing the display unit 24 (live view image).

[0036] Therefore, in the first embodiment, while the live view image cannot be displayed on the display unit 24, the body control unit 21 displays the distance image output from the distance measuring device 50 on the display unit 24 as an auxiliary image.

[0037] Hereinafter, the flow of the display control of the display unit 24 by the body control unit 21 will be described with reference to the flowcharts of FIGS. 2(a) and 2(b) and other drawings as appropriate.

[0038] The processes of FIGS. 2(a) and 2(b) are processes that start when the power of the camera body 2 is turned on and communication with the distance measuring device 50 becomes possible, and are executed simultaneously in parallel. When the process of FIG. 2(a) starts, first, in step S2, the body control unit 21 determines whether there is an imaging instruction from the photographer (whether the shutter button has been fully pressed). If the determination in this step S2 is negative, the process proceeds to step S4, and the body control unit 21 generates a live view image based on the signal output from the imaging element 22 and displays it on the display unit 24. Thereafter, the body control unit 21 repeats the process of step S4 until there is an imaging instruction from the photographer. On the other hand, if the determination in step S2 is affirmative, the process of step S4 is not performed, and the determination in step S2 is repeated until the determination in step S2 becomes negative (until the full press of the shutter button is released).

[0039] On the other hand, when the process of FIG. 2(b) starts, in step S10, the body control unit 21 requests the distance measuring device 50 to transfer distance images at predetermined time intervals.

[0040] Next, in step S12, the body control unit 21 receives a distance image from the distance measuring device 50. This step S12 is repeatedly executed at the above-mentioned predetermined time interval.

[0041] Next, in step S14, the body control unit 21 determines whether an image (live view image) based on the signal output from the imaging pixels of the pixel unit 221 is being displayed on the display unit 24 (whether step S4 in FIG. 2(a) is being executed). For example, when long-exposure shooting (continuous shooting) is being performed, the determination in this step S14 is negative, and the process proceeds to step S18. On the other hand, if the determination in step S14 is affirmative, the process proceeds to step S16.

[0042] When the process proceeds to step S16, the body control unit 21 displays an image (live view image) based on the signal output from the imaging pixels of the pixel unit 221 on the display unit 24. After that, the process returns to step S12.

[0043] On the other hand, when the process proceeds to step S18, the body control unit 21 displays the distance image on the display unit 24 as an auxiliary image. After that, the process returns to step S12.

[0044] When the process returns to step S12 after passing through step S16 or step S18, the processing of steps S12 to S18 is executed again. Note that the processing in FIGS. 2(a) and 2(b) is forcibly terminated when the power of the camera body 2 is turned off. Also, the processing in FIGS. 2(a) and 2(b) may be stopped as appropriate according to the operation of the photographer. For example, when the photographer performs an operation to display the menu screen, the body control unit 21 stops the processing in FIGS. 2(a) and 2(b) and displays the menu screen on the display unit 24.

[0045] FIG. 3 is a timing chart showing the processing timings of the camera body 2 and the distance measuring device 50 in the first embodiment.

[0046] In the distance measurement device 50, when the body control unit 21 receives a transfer request for a distance image by performing the process of step S10 in FIG. 2, as shown in FIG. 3, the exposure process, the output process, and the transfer process are repeatedly executed.

[0047] The exposure process is a process in which the light receiving pixel unit 502a receives the reflected light of the light emitted by the light emitting unit 501 and accumulates charges in the photoelectric conversion unit of each pixel of the light receiving pixel unit 502a. The output process is a process in which the control unit 503 generates a distance image based on information corresponding to the intensity of the reflected light. The transfer process is a process in which the control unit 503 transfers the generated distance image to the body control unit 21. Note that the control unit 503 may transfer a distance image within a range corresponding to the angle of view being imaged in the camera body 2, or may transfer all of the generated distance images.

[0048] Each time a distance image is transferred from the distance measurement device 50, the body control unit 21 of the camera body 2 makes the determination in step S14 in FIG. 2(b). And at the timing of the determination, if it is in a state where the live view image cannot be displayed, that is, when the accumulation process of still images for long exposure shooting is being performed and the accumulation process of the live view image has not been performed immediately before, the body control unit 21 displays the distance image (auxiliary image) on the display unit 24 (see "Distance Image Display 1-5" in FIG. 3).

[0049] On the other hand, if the live view image can be displayed at the timing of the determination, the body control unit 21 displays an image (live view image) based on the signal output from the imaging pixels on the display unit 24 (see S2 in FIG. 2(a), "Live View Display" in FIG. 3).

[0050] In this way, the body control unit 21 displays the distance image transferred from the distance measuring device 50 on the display unit 24 during periods when a live view image cannot be displayed on the display unit 24, allowing the photographer to capture images while checking the position of the subject within the frame, such as during long exposure shooting. This allows the photographer, when performing panning, to continue adjusting the shooting direction so that the subject is positioned in the same position in the frame during shooting. This makes it possible to capture appropriate images with panning.

[0051] As described above in detail, according to the first embodiment, the camera body 2 includes a display unit 24 that displays an image, and a body control unit 21 that selects either an image (live view image) generated based on a signal output from the pixel unit 221 of the image sensor 22 or a distance image (auxiliary image) received from the distance measuring device 50 and displays it on the display unit 24. This allows the distance image to be displayed on the display unit 24 during periods when the image generated based on the signal output from the pixel unit 221 of the image sensor 22 cannot be displayed on the display unit 24, thereby preventing blackouts from occurring when performing long exposure photography such as panning. Therefore, the photographer can confirm the position of the subject within the frame from the auxiliary image displayed on the display unit 24 during long exposure photography, allowing long exposure photography (panning) to be performed while keeping the subject at approximately the same position within the frame. This allows panning images to be captured with reduced subject blur.

[0052] Furthermore, according to the first embodiment, the start and end timings of the accumulation process of the live view image and the exposure process in the distance measuring device 50 are differentiated. This makes it possible to transfer a distance image from the distance measuring device 50 to the camera body 2 at a time when the live view image cannot be displayed on the display unit 24.

[0053] In the first embodiment, the body control unit 21 displays an auxiliary image on the display unit 24 during a period when a live view image cannot be displayed on the display unit 24, but this is not limited to this. Even during a period when an image generated based on signals output from the imaging pixels of the pixel unit 221 can be displayed on the display unit 24, a distance image may be displayed as appropriate on the display unit 24. Furthermore, for repeated ranging and accumulation, the ranging time and accumulation time may be different for each run.

[0054] In the first embodiment, the control unit 503 of the distance measuring device 50 may generate only an image in which the pixel values represent distances, instead of a distance image, and output this to the body control unit 21. In this case, the body control unit 21 may generate a distance image based on the acquired information about the distance to the object, and display it on the display unit 24. For example, a common method is to display the image in a different color depending on the distance, but the display method is not limited to this.

[0055] Second Embodiment The second embodiment will be described in detail below with reference to Figures 4 to 5(b). The configuration of the camera 1 of the second embodiment is the same as that of the first embodiment described above, so a description thereof will be omitted.

[0056] In the second embodiment, body control unit 21 controls image sensor 22 and distance measuring device 50, and drives focus lens 31b based on the outputs from each. More specifically, body control unit 21 controls the drive of focus lens 31b based on signals output from focus detection pixels in pixel unit 221, and controls the drive of the focus lens based on the distance image output from distance measuring device 50 during periods when drive control based on signals output from these focus detection pixels cannot be performed.

[0057] FIG. 4 is a flowchart showing the flow of processing of the body control unit 21 in the second embodiment. The processing in FIG. 4 starts when the power of the camera body 2 is turned on and communication with the distance measuring device 50 becomes possible. When the processing in FIG. 4 starts, in step S30, the body control unit 21 waits until an AF instruction is received. When an AF instruction (half-pressing of the shutter button) is received from the photographer, the process proceeds to step S32, and the body control unit 21 outputs a distance measurement process start instruction to the control unit 503 of the distance measuring device 50.

[0058] Thereafter, the body control unit 21 executes the processing in step S34 and the processing in step S36 in parallel.

[0059] In step S34, the body control unit 21 receives a distance image from the distance measuring device 50. On the other hand, in step S36, the body control unit 21 executes a focus detection process. Note that the processes in steps S34 and S36 may or may not be performed at the same timing. Therefore, in FIG. 4, after step S32, when at least one of the processes in steps S34 and S36 is performed, the process proceeds to step S37.

[0060] When the process proceeds to step S37, the body control unit 21 determines whether there is a shooting instruction (whether the shutter button has been fully pressed). If the determination in this step S37 is affirmative, the body control unit 21 proceeds to step S38 and executes a shooting process. Thereafter, the process returns to step S30. Note that it is assumed that the distance measuring device 50 performs a distance measurement process even while the shooting process in step S38 is being performed in the camera body 2. On the other hand, if the determination in step S37 is negative, the process proceeds to step S39.

[0061] When shifting to step S39, the body control unit 21 determines whether the focus lens 31b can be driven using the result of the focus detection process. That is, the body control unit 21 determines whether the result of the focus detection process has been obtained (whether step S36 has been performed) in the parallel processing of the immediately preceding steps S34 and S36. If the determination in this step S39 is affirmed, the body control unit 21 shifts to step S40.

[0062] When shifting to step S40, the body control unit 21 drives the focus lens based on the result of the focus detection process. Thereafter, it shifts to step S44, and the body control unit 21 determines whether the AF instruction has been canceled. If the determination in this step S44 is negated, it returns to steps S34 and S36. On the other hand, if the determination in step S44 is affirmed, it returns to step S30.

[0063] On the other hand, if the determination in step S39 is negated, that is, if the result of the focus detection process could not be obtained in the parallel processing of the immediately preceding steps S34 and S36, the body control unit 21 shifts to step S42 and drives the focus lens 31b based on the distance image. When driving the focus lens based on the distance image, distance information in a range corresponding to the AF area set in the most recent focus detection process (S36) is obtained from the distance image. Then, based on the following formula (1), the target lens position (moving target position) of the focus lens 31b is calculated, and the focus lens 31b is driven to the calculated target lens position. Target lens position = Constant A ÷ Distance …(1)

[0064] Note that the constant A is assumed to be a predetermined value (design value). The constant A may be stored, for example, in the lens memory 33 of the interchangeable lens 3 and read out as appropriate, or may be stored in the body memory 23 of the camera body 2.

[0065] After that, the process proceeds to step S44, and the body control unit 21 determines whether or not the AF instruction (half-pressing of the shutter button) has been released. If the determination in this step S44 is negative, the process returns to steps S34 and S36. On the other hand, if the determination in step S44 is affirmative, the process returns to step S30.

[0066] Note that the process of FIG. 4 is forcibly terminated when the power of the camera body 2 is turned off. Also, the process of FIG. 4 may be appropriately stopped according to the operation of the photographer.

[0067] FIG. 5(a) is a timing chart showing the processing timings of the camera body 2 and the distance measuring device 50 in the second embodiment. As an example, FIG. 5(a) shows a case where a still image is taken by fully pressing the shutter button, then the shutter button is half-pressed, and then the shutter button is fully pressed again to take a still image.

[0068] In the distance measuring device 50, when a transfer request for a distance image is received (when the body control unit 21 executes the process of step S32 in FIG. 4), as in the first embodiment, as shown in FIG. 5(a), the exposure process, the output process, and the transfer process are repeatedly executed at predetermined time intervals.

[0069] On the other hand, in the camera body 2, when a still image is being taken (during "accumulation (still image)" in FIG. 5(a)), the focus detection process cannot be performed, but when a distance image is transferred from the distance measuring device 50, a drive amount calculation is performed based on the distance image (see reference numerals B1 and B2 in FIG. 5(a)).

[0070] After that, when the shutter button is half-pressed, during the half-pressing (during time H in FIG. 5(a)), since the focus detection process (S36) can be performed, the body control unit 21 repeatedly executes the accumulation (live view) process, the AF calculation process, the drive amount calculation process, and the drive process at predetermined time intervals as shown by the frame filled with gray in FIG. 5(a).

[0071] The accumulation (live view) process is a process in which light is received by the focus detection pixels of the pixel unit 221 and electric charges are accumulated in the photoelectric conversion units of the focus detection pixels. The AF calculation process executes focus detection processing based on signals from the focus detection pixels and calculates the target lens position of the focus lens 31b based on equation (2). Target lens position = Current lens position + L (Focus detection result) ... (2) L is a function for converting the focus detection result into the lens drive amount, and the coefficients required for the conversion are data received from the lens memory 33.

[0072] In this second embodiment, while the shutter button is half-pressed (during time H), and while it is not possible to drive the focus lens 31b based on the signal output from the focus detection pixel, the body control unit 21 drives the focus lens 31b based on the distance image (see symbols C1 and C2 in Figure 5(a)).

[0073] On the other hand, while the shutter button is half-pressed (during time H), if it is possible to drive the focus lens 31b based on the signal output from the focus detection pixel, the body control unit 21 drives the focus lens 31b based on the result of the focus detection process.

[0074] Fig. 5(b) is a diagram showing a comparative example, in which focus lens 31b is driven based only on signals output from focus detection pixels, without using a distance image transferred from distance measuring device 50.

[0075] In the second embodiment (FIG. 5(a)), after a still image is captured, focus lens 31b can be driven based on the distance image during the time it takes for focus lens 31b to be driven based on focus detection processing (references C1 and C2). On the other hand, in the comparative example of FIG. 5(b), after a still image is captured, it takes a long time before focus lens 31b can be driven.

[0076] That is, in the comparative example (Fig. 5(b)), since the time until the focus lens 31b is driven is long, if the object moves significantly during that time, the driving amount of the focus lens 31b may increase. For this reason, when a shooting instruction is input from the photographer, the time until a still image can be taken becomes long, and there is a risk of delay in shooting. Alternatively, there is a risk of shooting before driving the focus lens 31b. On the other hand, in this second embodiment, after shooting a still image, since the time until the focus lens 31b can be driven is short, a still image can be taken in a focused state immediately after a shooting instruction is input from the photographer.

[0077] As described above, in this second embodiment, the body control unit 21 controls the imaging element 22 and the distance measuring device 50, and drives the focus lens 31b based on the outputs from each. Thereby, the number of driving times of the focus lens 31b can be increased. More specifically, in this second embodiment, when the body control unit 21 cannot drive the focus lens 31b based on the focus detection signal output from the focus detection pixels of the pixel unit 221 at the timing of acquiring the distance image generated by the distance measuring device 50, the focus lens 31b is driven based on the distance image. Thereby, compared with the case of driving the focus lens 31b based only on the focus detection signal (comparative example), since the driving frequency of the focus lens 31b can be increased, the time from when a shooting instruction is input until shooting starts can be shortened.

[0078] Also, in this second embodiment, the driving of the focus lens 31b based on the focus detection signal is preferentially performed rather than the driving of the focus lens 31b based on the distance image. Thereby, the driving accuracy (autofocus accuracy) of the focus lens 31b can be maintained high.

[0079] In the second embodiment described above, the case has been described in which body control unit 21 drives focus lens 31b based on a distance image acquired from distance measuring device 50, but this is not limited to this. For example, instead of a distance image, control unit 503 of distance measuring device 50 may generate data that can calculate the distance to the object (for example, data including time Δt for each pixel) and output this to body control unit 21. In this case, body control unit 21 may drive focus lens 31b based on this data.

[0080] In the second embodiment, the case where the formula (1) is used to calculate the target lens position based on the distance information is described, but this is not limiting and other formulas may be used. Furthermore, for the repeated distance measurement and accumulation, the distance measurement time and accumulation time may be different for each time.

[0081] Third Embodiment Next, a third embodiment will be described in detail with reference to Figures 6 to 7(b). The configuration of the camera 1 of the third embodiment is the same as that of the first and second embodiments described above, so a description thereof will be omitted.

[0082] The third embodiment is characterized in that the timing of the accumulation process of the focus detection process executed in the camera body 2 and the timing of the exposure process of the distance image executed in the distance measuring device 50 are shifted.

[0083] 6 is a flowchart showing drive control of focus lens 31b by body control unit 21 in the third embodiment. The processing in FIG. 6 starts when power to camera body 2 is turned on and communication with distance measuring device 50 becomes possible.

[0084] 6 starts, first, in step S50, body control unit 21 determines the timing of focus detection processing and distance measurement processing. For example, body control unit 21 determines the timing of each processing so that, while storage processing is being performed in camera body 2, drive amount calculation and drive of focus lens 31b are performed using a distance image transferred from distance measuring device 50.

[0085] Next, in step S52, the body control unit 21 waits until it receives an AF command. When it receives an AF command (halfway pressing the shutter button) from the photographer, it proceeds to step S54, where the body control unit 21 drives the focus lens based on the output signals of the focus detection pixels, or drives the focus lens based on a distance image. In step S54, if the body control unit 21 has previously acquired output signals of the focus detection pixels, it drives the focus lens based on the output signals of the focus detection pixels. On the other hand, if the body control unit 21 has previously acquired a distance image, it drives the focus lens based on the distance image.

[0086] Next, in step S56, the body control unit 21 determines whether or not a shooting instruction has been received from the photographer (whether or not the shutter button has been fully pressed). If the determination in step S56 is negative, the process returns to step S54. On the other hand, if the determination in step S56 is positive, the process proceeds to step S58.

[0087] When the process proceeds to step S58, the body control unit 21 generates an image based on the output signals from the pixel unit 221 (imaging pixels) and stores the image in the body memory 23. After that, the body control unit 21 returns to step S52. After returning to step S52, the processes and determinations of steps S52 to S58 are repeatedly executed until the power to the camera body 2 is turned off.

[0088] FIG. 7(a) is a timing chart showing the processing timings of the camera body 2 and the distance measuring device 50 in the third embodiment. In this third embodiment, as shown in FIG. 7(a), the driving process of the focus lens 31b based on the output signal of the focus detection pixels indicated by the thick white frame and the driving process of the focus lens 31b based on the distance image indicated by the thick gray frame are out of sync. The accumulation process in the focus detection element and the exposure process timing in the distance measuring device 50 are set. In this third embodiment, the time required for the accumulation process and the time required for the exposure process in the distance measuring device are different, and the start timing and the end timing of each process are different.

[0089] FIG. 7(b) is a diagram showing a comparative example. The comparative example in FIG. 7(b) is an example in which the focus lens driving based on the distance image is not executed, and only the focus lens driving based on the output signal of the focus detection pixels is executed. As can be seen by comparing FIGS. 7(a) and 7(b), in this third embodiment (FIG. 7(a)), the number of times the focus lens 31b is driven can be increased. By doing so, for example, even when the object moves at high speed within the frame, the movement of the object can be tracked. Thereby, it is possible to suppress the focus from becoming soft (the object being out of focus) at the timing when the object starts to move.

[0090] As described in detail above, according to this third embodiment, the body control unit 21 makes the timing at which the focus lens 31b can be driven based on the distance image of the distance measuring device 50 different from the timing at which the focus lens 31b can be driven based on the output signal from the focus detection pixels of the pixel unit 221. As a result, the focus lens 31b can be driven based on the distance image during the time when the focus lens 31b cannot be driven based on the output signal from the focus detection pixels. In this way, by increasing the number of times (driving frequency) the focus lens 31b is driven, it becomes possible to continuously focus on the object even if the object moves at high speed.

[0091] In the above-described embodiment, the timing at which the light reception by the light reception unit 502 (exposure in FIG. 7(a)) ends is made different from the timing at which the light reception by the focus detection pixels of the pixel unit 221 (accumulation in FIG. 7(a)) ends. In this case, for example, when the light reception time by the light reception unit 502 and the light reception time by the focus detection pixels are of the same length, the timing at which the light reception ends can be made different by making the timing at which the light reception starts different. Also, regarding the repeatedly performed distance measurement and accumulation, the distance measurement time and the accumulation time for each time may be different.

[0092] (Modification example) In the above-described third embodiment, when the body control unit 21 drives the focus lens 31b based on the distance image, it may determine whether the driving amount of the focus lens 31b exceeds a predetermined range, and if it exceeds, may not drive the focus lens 31b. The predetermined range means the driving amount of the focus lens 31b corresponding to the distance that the object can move after the driving of the focus lens 31b based on the output signal of the immediately preceding focus detection pixel. That is, the predetermined range is set to be larger if the time after driving the focus lens 31b based on the output signal of the focus detection pixel immediately before is longer, and smaller if the time is shorter. By doing so, for example, when photographing a bird as the object but misrecognizing the grass or trees behind the bird as the object (when the driving amount of the focus lens 31b is more than expected), the possibility of focusing on the grass or trees behind can be reduced.

[0093] 《Fourth Embodiment》 Next, the fourth embodiment will be described in detail with reference to FIGS. 8 to 10. Since the configuration of the camera 1 in this fourth embodiment is the same as that in the first to third embodiments described above, the description thereof will be omitted.

[0094] This fourth embodiment is characterized in that the constant A in the formula (1) (target lens position = constant A ÷ distance) described in the second embodiment is appropriately calibrated (corrected). In this fourth embodiment, resetting the constant A is called calibration.

[0095] In the fourth embodiment, when an AF instruction is input from the photographer (when the shutter button is half-pressed), as shown in FIG. 8, the camera body 2 repeats accumulation processing, AF calculation processing, and driving processing. Further, in the distance measuring device 50, as distance measuring processing, exposure processing and output processing are repeated, and in the camera body 2, driving processing based on the result of the distance measuring processing is performed. In FIG. 8, for convenience of explanation, it is assumed that the "driving" processing includes the "driving amount calculation" processing and the "driving processing" illustrated in FIGS. 5(a) of the second embodiment and 7(a) of the third embodiment. Also, in FIG. 8, the "transfer" processing illustrated in FIGS. 5(a) and 7(a) is omitted.

[0096] FIG. 8 illustrates a case where the time required for the accumulation processing on the camera body 2 side is the same as the time required for the distance measuring processing on the distance measuring device 50 side, that is, the period during which the imaging element 22 receives light to obtain a focus detection signal and the period during which the light receiving unit 502 receives light to obtain a distance image coincide.

[0097] In the example of FIG. 8, the focus lens 31b is driven based on the result of the distance measuring process 1, then the focus lens 31b is driven based on the result of the accumulation process 1, then the focus lens 31b is driven based on the result of the distance measuring process 2, and then the focus lens 31b is driven based on the result of the accumulation process 2, and so on. In this way, the driving of the focus lens 31b based on the result of the distance measuring process and the driving of the focus lens 31b based on the result of the accumulation process are alternately and repeatedly executed. And in the driving of the focus lens 31b based on the result of the distance measuring process among these, the process as shown in FIG. 9 is executed.

[0098] FIG. 9 is a flowchart showing the processing executed by the body control unit 21 before performing the driving amount calculation of the focus lens 31b using the result of the distance measuring process. In the following, for convenience of explanation, the case where it is the stage before performing the driving amount calculation of the focus lens 31b using the result of the distance measuring process 2 in FIG. 8 (the stage at time T1 in FIG. 8) will be described.

[0099] 9 starts, first, in step S70, the body control unit 21 acquires the focus detection result immediately before. At time T1, the body control unit 21 acquires the focus detection result obtained as a result of accumulation process 1.

[0100] Next, in step S72, the body control unit 21 acquires a distance image obtained at the same timing as the focus detection result obtained in step S70. At time T1, the body control unit 21 acquires a distance image obtained as a result of distance measurement process 1.

[0101] Next, in step S74, the body control unit 21 determines whether or not a distance image was acquired by the processing of step S72. If the determination in step S74 is positive, the process proceeds to step S76, where the calculation formula is calibrated using the acquired focus detection result and distance image (the constant A in calculation formula (1) is corrected).

[0102] Specifically, the body control unit 21 calibrates the constant A(n+1) used to determine the target lens position based on the distance measurement value of distance measurement process (n+1), using the distance measurement value output D(n) of distance measurement process n and the lens position AFL(n) obtained as a result of accumulation process n. When the calibrated constant is A'(n+1), A'(n+1) can be calculated using the following equation (3): A'(n+1)=D(n)×AFL(n) …(3)

[0103] Therefore, for example, the constant A(2) used at time T1 in Fig. 8 is A(2) = D(1) × AFL(1). Also, for example, the constant A(5) used at time T2 in Fig. 8 is A(5) = D(4) × AFL(4).

[0104] After the process of step S76 is performed as described above, all the processes in Fig. 9 are completed. Also, if the determination in step S74 is negative, all the processes in Fig. 9 are completed without going through the process of step S76.

[0105] An overview of the fourth embodiment is shown in Figure 10. The middle section of Figure 10 schematically shows changes in the target lens position. In the middle section of Figure 10, the target lens position of focus lens 31b based on the focus detection result is indicated by a black circle (●), and the target lens position of focus lens 31b based on the distance image is indicated by a white circle (◯).

[0106] 10 , in the fourth embodiment, calibration 1 of constant A (calculation of A(2)) is performed based on the results of distance measurement process 1 and AF calculation process 1, and when calculating the target lens position (movement target position of focus lens 31b) based on the result of distance measurement process 2, the constant A(2) calibrated by calibration 1 is used. Furthermore, calibration 2 of constant A (calculation of A(3)) is performed based on the results of distance measurement process 2 and AF calculation process 2, and when calculating the target lens position based on the result of distance measurement process 3, the constant A(3) calibrated by calibration 2 is used. In this way, by calibrating constant A from the relationship between the AF calculation result obtained at the same timing and the distance based on the distance image, it is possible to accurately calculate the target lens position based on distance information immediately afterwards.

[0107] In the fourth embodiment, it can be said that the body control unit 21 calibrates the movement target position of the focus lens 31b based on the distance image, using the movement target position of the focus lens 31b based on the focus detection signal.

[0108] As described above in detail, according to the fourth embodiment, the movement target position of focus lens 31b based on the focus detection signal is used to calibrate the movement target position of focus lens 31b based on the distance image. More specifically, the constant A(n+1) in equation (1) is calibrated based on the result of distance measurement process n and the result of AF calculation process n performed simultaneously with distance measurement process n. As a result, when calculating the target lens position based on the distance image obtained in distance measurement process (n+1), the constant A(n+1) can be used to accurately calculate the target lens position. Note that the distance measurement time and accumulation time for each repeated distance measurement and accumulation may be different.

[0109] (Modification Example 1) FIG. 11 is a diagram showing an overview of Modification Example 1 of the fourth embodiment. This Modification Example 1 shows a case where the time required for the accumulation process on the camera body 2 side is longer than the time required for the distance measurement process on the distance measurement device 50 side.

[0110] In this Modification Example 1, the focus lens 31b is driven in the order of driving of the focus lens 31b based on the distance measurement process 1, driving of the focus lens 31b based on the distance measurement process 2, driving of the focus lens 31b based on the accumulation process 1,.... Then, in the driving of the focus lens 31b based on the result of the distance measurement process among these, the same process as in FIG. 9 is executed.

[0111] For example, assuming that the body control unit 21 performs the process of FIG. 9 at the time point T3 in FIG. 11 (the stage of driving the focus lens 31b based on the distance measurement process 3). In this case, the body control unit 21 acquires the focus detection result of the accumulation process 1 (that is, the result of the AF calculation process 1) as the immediately previous focus detection result (S70). Next, the body control unit 21 acquires the distance image obtained at the same timing as the acquired focus detection result (S72). In this case, the body control unit 21 acquires the distance image of the distance measurement process 1 that is executed overlapping with the accumulation process 1. Then, the body control unit 21 calibrates the calculation formula (constant A) using the acquired focus detection result and distance image (S76, refer to "Calibration 1" in FIG. 11).

[0112] Also, assume that at time point T4 in FIG. 11 (the stage of driving the focus lens 31b based on the distance measurement process 4), the body control unit 21 performs the process of FIG. 9. In this case, the body control unit 21 acquires, as the immediately previous focus detection result, the focus detection result of the accumulation process 1 (that is, the result of the AF calculation process 1) (S70). Next, the body control unit 21 acquires the distance image obtained at the same timing as the acquired focus detection result (S72). In this case, the body control unit 21 acquires the distance image of the distance measurement process 1 that is executed in duplicate with the accumulation process 1. Then, the body control unit 21 calibrates the calculation formula (constant A) using the acquired focus detection result and the distance image (see "Calibration 1" in FIG. 11) (S76). That is, the value used for calibrating the constant A at time point T4 is the same as the value used for calibrating the constant A at time point T3. Therefore, when using the same value as the immediately previous calibration as in the case of time point T4, the calibration calculation may be omitted.

[0113] Also, at time point T5 in FIG. 11 (the stage of driving the focus lens 31b based on the distance measurement process 5), the body control unit 21 first acquires, as the immediately previous focus detection result, the focus detection result of the accumulation process 2 (that is, the result of the AF calculation process 2) (S70). Next, the body control unit 21 acquires the distance image obtained at the same timing as the acquired focus detection result (S72). In this case, the body control unit 21 acquires the distance image of the distance measurement process 3 that is executed in duplicate with the accumulation process 2. Then, the body control unit 21 calibrates the calculation formula (constant A) using the acquired focus detection result and the distance image (see "Calibration 2" in FIG. 11) (S76).

[0114] As described above, according to the first modification example, the constant A is calibrated based on the result of the immediately previous accumulation process and the result of the distance measurement process performed at the same timing as the accumulation process. Thereby, even when calculating the target lens position based on the distance image, the target lens position can be calculated with high accuracy. Note that for the repeatedly performed distance measurement and accumulation, the distance measurement time and the accumulation time may be different each time.

[0115] (Second Modification Example) FIG. 12 is a diagram showing an outline of Modification 2 of the fourth embodiment. This Modification 2 shows a case where the time required for the accumulation process on the camera body 2 side is shorter than the time required for the distance measurement process on the distance measurement device 50 side.

[0116] In this Modification 2, the focus lens 31b is driven in the order of driving of the focus lens 31b based on the accumulation process 1, driving of the focus lens 31b based on the distance measurement process 1, driving of the focus lens 31b based on the accumulation process 2, driving of the focus lens 31b based on the accumulation process 3, driving of the focus lens 31b based on the distance measurement process 2,.... Then, in the driving of the focus lens 31b based on the result of the distance measurement process among these, the process of FIG. 13 is executed.

[0117] FIG. 13 is a flowchart showing the process executed by the body control unit 21 before performing the driving amount calculation of the focus lens 31b using the result of the distance measurement process. In the following, for convenience of explanation, a case where it is the stage before performing the driving amount calculation of the focus lens 31b using the result of the distance measurement process 2 in FIG. 12 (the stage of time point T12 in FIG. 12) will be described.

[0118] When the process of FIG. 13 is started, first, in step S170, the body control unit 21 acquires the distance measurement image obtained by the immediately preceding distance measurement process. At time point T12, the body control unit 21 acquires the distance measurement image obtained as the result of the distance measurement process 1.

[0119] Next, in step S172, the body control unit 21 acquires the focus detection result obtained as the result of the accumulation process performed at the same timing as the distance measurement process in which the distance image acquired in step S170 was obtained. Note that the accumulation process performed at the same timing as the distance measurement process means the accumulation process whose entire implementation period overlapped with the period of the distance measurement process. At time point T12, the body control unit 21 acquires the focus detection result obtained by the accumulation process 1 and the focus detection result obtained by the accumulation process 2.

[0120] Next, in step S174, the body control unit 21 determines whether the focus detection result could be obtained in step S172. If the determination in this step S174 is affirmative, the process proceeds to step S176, and the calculation formula is calibrated using the obtained focus detection result and the distance image (correcting the constant A in the calculation formula (1)).

[0121] Specifically, the body control unit 21 uses the average value AFL of the obtained result of the distance measurement process (distance measurement value output D) and the obtained result of the accumulation process (lens position). ave to calibrate the constant A. The calibrated constant A' is obtained by the following formula (4). A' = D × AFL ave …(4)

[0122] After the process of step S176 is performed as described above, the entire process in FIG. 13 ends. If the determination in step S174 is negative, the entire process in FIG. 13 ends without going through the process of step S176.

[0123] As described above, according to this second modification example, the constant A is calibrated based on the result of the immediately preceding distance measurement process and the result (average value) of the accumulation process performed at the same timing as the distance measurement process. Thereby, even when calculating the target lens position based on the distance image, the target lens position can be calculated with high accuracy.

[0124] In this second modification example, since the results (focus detection results) of the distance measurement process 2 and the accumulation process 3 are obtained, it is not necessary to drive the focus lens 31b based on the result of the distance measurement process 2. However, since the result of the accumulation process 3 may not be obtained, if the result of the accumulation process 3 is not obtained, the focus lens 31b may be driven based on the result of the distance measurement process 2. Regarding the repeatedly performed distance measurement and accumulation, the distance measurement time and the accumulation time may be different each time.

[0125] <<Fifth Embodiment>> Next, the fifth embodiment will be described in detail with reference to FIG. 14. Since the configuration of the camera 1 in the fifth embodiment is the same as that in the first to fourth embodiments described above, the description thereof will be omitted.

[0126] In the fifth embodiment, in order to frequently drive the focus lens 31b based on the focus detection result on the camera body 2 side (that is, to improve the AF speed), it is necessary to speed up the acquisition cycle of the focus detection result and perform accumulation processing at a high frame rate. However, when performing such accumulation processing at a high frame rate, there is a risk that the power consumption will increase.

[0127] Therefore, in the fifth embodiment, the following processing is executed. FIG. 14 shows an overview of the processing in the fifth embodiment.

[0128] When an AF instruction is input from the photographer (when the release button is half-pressed), first, as shown at time t1 in FIG. 14, the body control unit 21 starts distance measurement by the distance measurement device 50. Note that the distances (such as 10 m and 5 m) described below the distance measurement process in FIG. 14 mean the difference between the position of the object obtained from the distance image and the in-focus position of the interchangeable lens 3. This difference will be referred to as the "focus shift amount" hereinafter.

[0129] Thereafter, the body control unit 21 repeatedly drives the focus lens 31b based on the distance measurement by the distance measurement device 50, and each time it repeats, it determines whether the focus shift amount has become less than a predetermined value. When the focus shift amount becomes less than a predetermined value (for example, 2 m) (see time t2 in FIG. 14), the body control unit 21 starts driving the focus lens 31b based on the output signal of the focus detection pixel. That is, similar to the second embodiment described above, the focus lens 31b is driven using the distance image, and the focus lens 31b is also driven based on the output signal of the focus detection pixel.

[0130] By doing so, until time t2, the imaging device 22 is not made to output a signal (or charge is not accumulated in the photoelectric conversion section of the pixel section 221), and the focus lens 31b is not driven based on the focus detection result. Therefore, compared with the case where the focus lens 31b is driven based on the focus detection result from time t1, power consumption can be reduced.

[0131] As described above, according to the fifth embodiment, when the amount of focus deviation based on the distance image is less than a predetermined value, the body control unit 21 does not output a signal from the imaging device 22 (or does not accumulate charge in the photoelectric conversion section of the pixel section 221). Therefore, it is possible to reduce the power consumption in the camera body 2. Note that for the repeatedly performed distance measurement and accumulation, the distance measurement time and accumulation time for each time may be different.

[0132] (Modification example) In the above fifth embodiment, the case where focus detection using the focus detection pixels is not performed from time t1 to time t2, that is, until the amount of focus deviation becomes less than a predetermined value, has been described. However, the present invention is not limited to this.

[0133] For example, as shown in FIG. 15, the focus lens 31b is driven based on the focus detection result also from time t1 to time t2. However, the frequency of focus detection may be made lower than the frequency of focus detection after time t2 (the number of focus detections per unit time, the frame rate).

[0134] Even in this case, compared with the case where focus detection is performed at a high frequency from time t1, power consumption can be reduced.

[0135] In each of the above embodiments and modification examples, even while a still image is being taken in the camera body 2 (during still image exposure), there may be a case where a signal can be output from the focus detection pixels. In this case, the processing executed while receiving an AF instruction as described in each of the above embodiments and modification examples (during half-press) may be executed during still image exposure.

[0136] Note that the processes executed by the body control unit 21 described in the first to fifth embodiments and the modification examples may be arbitrarily combined.

[0137] Note that in each of the above embodiments and modification examples, the case where the distance measuring device 50 is detachable from the camera 1 has been described. However, the present invention is not limited to this, and the camera 1 may include the distance measuring device 50 (it may be an integrated type). In this case, the processes of FIGS. 2(a), 2(b), and 4 are started at the timing when the power of the camera body 2 is turned on.

[0138] Note that in each of the above embodiments and modification examples, the case where the camera 1 is an interchangeable-lens camera has been described. However, the present invention is not limited to this, and the camera 1 may be an integrated-lens camera.

[0139] The above-described embodiments are not limited thereto, and various modifications can be made without departing from the gist of the invention.

Explanation of Reference Numerals

[0140] 1 Camera 2 Camera Body 3 Interchangeable Lens 21 Body Control Unit 22 Image Sensor 31 Imaging Optical System 31b Focusing Lens 50 Distance Measuring Device 501 Light Emitting Unit 502 Light Receiving Unit 503 Control Unit

Claims

1. A distance measuring device having a light emitting unit that emits light, a light receiving unit that receives light reflected by an object from the light emitted by the light emitting unit, and a generation unit that generates information regarding the distance to the object based on the light receiving result of the light receiving unit; An imaging device including an imaging element that receives light that has passed through an optical system having a focus lens and outputs a signal; A control unit that controls the distance measuring device and the imaging element.

2. The imaging device according to claim 1, wherein the control unit controls at least one of the distance measuring device and the imaging element such that a timing at which the light receiving unit starts or ends light reception is different from a timing at which the imaging element starts or ends light reception.

3. The imaging element has pixels that output signals used for focus detection of the optical system, The imaging device according to claim 2, wherein the control unit controls such that a timing at which the light receiving unit starts or ends light reception is different from a timing at which the pixels start or end light reception.

4. The imaging device according to claim 3, wherein when the control unit starts moving the focus lens, the control unit controls the position of the focus lens based on the information regarding the distance to the object generated by the distance measuring device while the focus lens is not moving.

5. The imaging device according to claim 3, wherein the control unit controls the position of the focus lens based on the signal and controls the position of the focus lens based on the information regarding the distance to the object.

6. The imaging device according to claim 5, wherein the control unit controls the position of the focus lens when a movement amount of the focus lens based on the information regarding the distance to the object is within a predetermined range.

7. The imaging device according to claim 3, wherein the control unit calibrates a movement target position of the focus lens based on the information regarding the distance to the object using a movement target position of the focus lens based on the signal.

8. The imaging device according to claim 7, wherein the control unit controls the distance measuring device and the imaging element such that a period during which the light receiving unit receives light to obtain the information regarding the distance to the object used for calibration of the movement target position of the focus lens overlaps with a period during which the imaging element receives light to obtain the signal.

9. The imaging device according to any one of claims 1 to 8, comprising a display unit that displays at least one of an image generated based on a signal output from the imaging element and an image based on information regarding the distance to the object.

10. The imaging device according to claim 9, wherein the display unit displays an image based on information regarding the distance to the object during a period when an image generated based on a signal output from the imaging element is not being displayed.

11. The imaging element has pixels that output signals used for focus detection of the optical system, The imaging device according to claim 1, wherein the control unit changes the number of times the imaging element outputs the signal per unit time when the distance based on the information regarding the distance to the object becomes less than a predetermined distance.

12. The imaging device according to claim 11, wherein the control unit makes the number of times the imaging element outputs the signal per unit time when the distance based on the information regarding the distance to the object is less than the predetermined distance greater than the number of times the imaging element outputs the signal per unit time while the distance based on the information regarding the distance to the object is greater than or equal to the predetermined distance.

13. The imaging device according to claim 11, wherein the control unit makes the number of times the photoelectric conversion unit of the pixel accumulates charge per unit time when the distance based on the information regarding the distance to the object is less than the predetermined distance greater than the number of times the photoelectric conversion unit of the pixel accumulates charge per unit time while the distance based on the information regarding the distance to the object is greater than or equal to the predetermined distance.

14. The imaging device according to any one of claims 1 to 13, wherein the distance measuring device is detachable from the imaging device.

Images