JP2007295240A - Imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging apparatus constituted so that a user can easily confirm information about the reliability of flange-back adjustment or the like. <P>SOLUTION: The imaging apparatus 34 comprises an evaluation value generation means 28 for generating a focus evaluation value expressing a focused state from a video signal obtained by using imaging elements 21 to 23, and display signal generating means 29 to 32 for generating a display signal for displaying information indicating relation between the position of a focus lens attached to an interchangeable lens and the focus evaluation value. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an imaging apparatus such as a video camera, and more particularly to an imaging apparatus that outputs information usable for flange back adjustment and the like.

  As disclosed in Patent Document 1, the interchangeable lens imaging device has a function of electrically adjusting the flange back in order to match the flange back of the interchangeable lens with the flange back of the imaging device. There is.

  Further, Patent Document 2 discloses an interchangeable lens that can automatically perform back focus adjustment. This interchangeable lens drives the back focus adjustment lens based on the difference between the flange back information of the photographing device to which the interchangeable lens is attached and the flange back information of the photographing device to which the lens device is actually attached at the time of assembly and adjustment. To do.

  Further, in Patent Document 3, in order to enable stable photographing without being affected by temperature change, information necessary for correcting the imaging plane position accompanying temperature change is transmitted to the lens device, An imaging apparatus that drives a movable lens based on information has been proposed.

  However, in the conventional flange back adjustment, both the error caused by combining the flange back information set for the interchangeable lens and the flange back information set for the image pickup apparatus and the error caused by the influence of the temperature change are both included. Could not cope with.

In order to solve this, it is considered that the most effective means is to obtain a correction value most suitable for the temperature at the time of adjustment by performing a flange back adjustment by the user.
JP 2000-121911 (paragraphs 0028 to 0034, FIG. 3, etc.) JP 2003-131103 A (paragraphs 0121 to 00137, FIG. 5 and the like) Japanese Patent Laid-Open No. 11-84501 (paragraph 0052, FIG. 1, etc.)

  However, when the user performs flange back adjustment, the reliability of the adjustment may be low depending on the brightness, color, shape, and distance of the subject that is being photographed at that time. In this case, it is desirable to perform readjustment while changing the subject, but conventionally there has been no means for the user to confirm the reliability of adjustment.

  An object of the present invention is to provide an imaging apparatus that allows a user to easily check information such as the reliability of flange back adjustment.

  An imaging apparatus according to an aspect of the present invention includes an evaluation value generation unit that generates a focus evaluation value that represents a focus state from a video signal obtained by using an imaging element, and a position of a focus lens provided in an interchangeable lens. And display signal generating means for generating a display signal for displaying information indicating a relationship with the focus evaluation value.

  In addition, an imaging apparatus according to another aspect of the present invention includes an evaluation value generation unit that generates a focus evaluation value representing a focus state from a video signal obtained using an imaging element, and focus control performed in an interchangeable lens. And determining means for determining whether or not the focus evaluation value satisfies a predetermined condition in a state where in-focus is obtained.

  According to the present invention, the focus evaluation value for the position of the focus lens can be confirmed by display means such as a monitor. For this reason, the reliability of flange back adjustment can be improved by using this function for flange back adjustment, for example. Moreover, it can be easily determined whether readjustment is necessary.

  Further, according to the present invention, it is determined whether or not the focus evaluation value satisfies a predetermined reliability condition in a state where focus is obtained by focus control, that is, whether or not the focus position obtained by focus control is reliable. can do. Therefore, by using this function, for example, for flange back adjustment, it is possible to easily determine whether or not flange back readjustment is necessary, and as a result, the reliability of flange back adjustment can be increased. .

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows a configuration of a camera system including a digital video camera as an imaging apparatus according to an embodiment of the present invention and an interchangeable lens attached to the camera.

  In FIG. 1, reference numeral 12 denotes an interchangeable lens provided with a photographing optical system. The photographing optical system includes a fixed first lens 1, a second lens (variator lens) 2 that performs zooming, a diaphragm 3, a fixed third lens 4, a focus function and a compensator function that corrects image plane movement accompanying zooming. And a fourth lens (focus lens) 5 including

  A light beam from a subject passes through a photographing optical system and enters a color separation prism (not shown) in a video camera body (hereinafter simply referred to as a camera) 34, and three primary color lights (red light, Green light and blue light). Red light forms an image on the image sensor 21, green light forms an image on the image sensor 22, and blue light forms an image on the image sensor 23. The image sensors 21, 22, and 23 are configured by CCD sensors or CMOS sensors.

  The positions of the variator lens 2 and the focus lens 5 in the optical axis direction are detected by position sensors 51 and 52 such as encoders, and the detection information is supplied to the lens microcomputer 10.

  The image sensors 21, 22, and 23 photoelectrically convert subject images, respectively, and outputs are amplified to optimum levels by amplifiers 25, 26, and 27, and input to the camera signal processing circuit 28. It is converted into a video signal such as a standard television signal. The video signal is sent to the display unit 61 via the video superimposing circuit 33, whereby the captured video is displayed on the display unit 61. The video signal is recorded on a recording medium (not shown) (semiconductor memory, optical disk, magnetic tape, etc.) through compression processing or the like.

  Further, the camera signal processing circuit 28 extracts a high frequency component from the video signal, and generates an AF evaluation value representing the contrast state of the video, that is, the focus state of the photographing optical system. The AF evaluation value is generated, for example, by taking the absolute value of the high-frequency component extracted from the video signal and integrating the absolute value data within a predetermined image area. The AF evaluation value signal is read as data by the AF data reading program of the camera microcomputer 29.

  The AF evaluation value read by the camera microcomputer 29 is combined with switch information such as ON / OFF of an AF selection switch (not shown) provided on the camera 34 side and the state of the zoom switch, and the camera side contact 30 and the lens side contact. 11 and transferred to the lens microcomputer 10.

  The lens microcomputer 10 sends a signal to the zoom motor driver 7 to drive the variator lens 2 in the TELE or WIDE direction in accordance with the zoom switch information from the camera microcomputer 29. The zoom motor driver 7 drives the variator lens 2 via the zoom motor 6.

  The cam data storage unit 10a in the lens microcomputer 10 stores lens cam data, which will be described later. The lens microcomputer 10 sends a signal to the focus motor driver 9 based on the lens cam data and moves the focus lens 5 via the focus motor 8 in accordance with the zooming caused by the movement of the variator lens 2. Thereby, zooming without focus fluctuation can be performed.

  In the present embodiment, since the focus lens 5 is a rear focus type in which the focus lens 5 is disposed rearward (image side) with respect to the variator lens 2, the image plane position changes with zooming. For this reason, the focus lens 5 is moved based on the lens cam data described above to maintain the in-focus state. The position of the focus lens 5 for maintaining focus according to the zoom position varies depending on the subject distance. Therefore, as shown in FIG. 5A, the lens cam data is stored as data indicating the position of the focus lens 5 according to the position of the variator lens 2 and the subject distance (for example, 1 m, 2 m). .

  The lens microcomputer 10 determines the rotation direction and the rotation amount of the focus motor 8 using the lens cam data selected by the position information of the variator lens 2 detected by the position sensor 51 and the subject distance information. The subject distance is calculated from the position of the variator lens 2 and the position of the focus lens 5 detected by the position sensor 52.

  When the AF switch is ON, the AF control unit 10b in the lens microcomputer 10 sends a signal to the focus motor driver 9 so that the AF evaluation value received from the camera microcomputer 29 is maximized. Move. Thereby, autofocus (AF) is performed.

  Here, regarding the driving of the focus lens 5 based on the lens cam data, it is necessary to determine an origin for ensuring accurate back focus. The origin is determined by correcting with a predetermined correction value using a predetermined reference value as a reference. The predetermined correction value here is a total value of the correction value held in the memory in the lens microcomputer 10 by the interchangeable lens 12 and the correction value transmitted from the camera 34.

  The correction value on the interchangeable lens 12 side is a fixed correction value due to variations in manufacturing errors and the like that occur at the stage of manufacturing the interchangeable lens 12, and fluctuations due to changes in optical characteristics due to temperature changes in the photographing optical system. It is a total value with a typical correction value.

  The correction value on the camera 34 side is a fixed correction value caused by variations in manufacturing errors and the like that occur at the stage of manufacturing the camera 34, and flange back fluctuation due to temperature change with respect to the flange back value set at the time of shipment from the factory. This is a total value with a variable correction value for correction. The camera 34 is provided with a temperature detection element 24, and a correction value for the flange back fluctuation can be obtained according to the output (temperature) from the temperature detection element 24.

  However, if the reference value based on the correction value on the interchangeable lens 12 is different from the reference value based on the correction value on the camera 34 side, the correction value transmitted on the interchangeable lens 12 side and the correction transmitted from the camera 34 are used. An error occurs when combining values. The present embodiment relates to a flange back adjustment method for obtaining an adjustment value for correcting an error due to this combination. More specifically, the present invention relates to a method for enabling easy confirmation of the accuracy (reliability) of the flange back adjustment, particularly when the user performs the flange back adjustment.

  The display unit 61 displays the video signal (subject image) as described above, or displays an image for flange back adjustment described later. The camera 34 according to the present embodiment has a normal mode in which a normal subject is captured and a captured image is displayed on the display unit 61. In addition, it has an adjustment mode for performing the flange back adjustment operation and displaying an adjustment image (a menu screen or an AF evaluation value graph image described later) on the display unit 61. These mode switching can be performed by a mode switching switch 63 provided in the camera 34.

  FIG. 2 shows a menu screen on the display unit 34 when the camera 34 is set to the adjustment mode. In this embodiment, it is possible to select AF adjustment in which the flange back adjustment is performed using the AF function and MF adjustment in which the manual focus (MF) is used. The adjustment value initialization is an operation to return the flange back information on the camera 34 side to the factory setting value.

  FIG. 3 shows a basic procedure of flange back adjustment performed in this embodiment. When the adjustment mode is selected by the mode switch 63, the camera microcomputer 29 enters the adjustment mode. When the user selects AF adjustment on the menu screen for flange back adjustment, the camera microcomputer 29 first moves the variator lens 2 to the TELE end in step (abbreviated as S in the figure) 1. In step 2, an AF command is transmitted to the lens microcomputer 10, and the focus lens 5 is moved by focus control by the AF control unit 10b to focus on a specific subject. Then, the variator lens 2 is moved to the WIDE end in step 3 while the focus lens 5 is held at the in-focus position.

  In step 4, the camera microcomputer 29 reads the current position of the focus lens 5, that is, the focus position f1 at the TELE end. Next, in step 5, an AF command is transmitted to the lens microcomputer 10, and the focus lens 5 is moved by focus control by the AF control unit 10b to focus on the specific subject.

  In step 6, the current position of the focus lens 5, that is, the focus position f2 at the WIDE end is read.

  Next, in step 7, an adjustment value is calculated using (f1-f2) and the lens coefficient set for the interchangeable lens 12. Then, the calculated adjustment value and the flange back information set at the stage of manufacturing the camera 34 are summed, and this is stored in a memory (not shown) in the camera microcomputer 29 as new flange back information. . If the user has performed flange back adjustment on the interchangeable lens 12 before this time, the sum of the adjustment value calculated this time and the flange back information stored as a result of past adjustments is obtained. Is stored in the memory as new flange back information.

  Next, in step 8, the adjustment value obtained in step 7 is corrected by temperature, and the adjustment value after the temperature correction is transmitted to the lens microcomputer 10. This makes it possible to correct the flange back error that occurs when the interchangeable lens 12 and the camera 34 are combined. This will be described later.

  On the other hand, when the user selects MF adjustment on the menu screen, flange back adjustment is performed in the same manner as AF adjustment, except that the focus is adjusted by the user's manual focus operation in steps S2 and S5. New flange back information and an adjusted value after temperature correction are obtained.

  Next, processing on the interchangeable lens 12 side using the adjustment value obtained in the above flange back adjustment will be described.

  The adjustment value transmitted from the camera microcomputer 29 is subjected to predetermined processing as a correction value in the lens microcomputer 10. In the lens microcomputer 10, lens cam data is stored as ideal values (design values) as shown in FIG. The ideal lens cam data is corrected as follows.

  If the adjustment value (flange back change information) transmitted from the camera 34 side is positive, the flange back (or back focus) is longer than the ideal value. Therefore, the adjustment value is obtained from the ideal lens cam data. The subtracted data is handled as lens cam data. This is equivalent to the fact that the adjusted lens cam data is shifted downward parallel to the ideal lens cam data, as indicated by the dotted line in FIG. Then, by performing focus correction control of the focus lens 5 with the new lens cam data after the adjustment, zooming can be performed while maintaining the in-focus state. If the adjustment value is negative, the flange back (or back focus) is smaller than the ideal value, and data obtained by adding the adjustment value to the ideal lens cam data is handled as lens cam data. This is equivalent to the fact that the adjusted lens cam data is shifted in parallel upward in FIG. 5 with respect to the ideal lens cam data.

  Here, FIGS. 6 and 7 show the relationship between the focus position and the AF evaluation value. The horizontal axis indicates the position of the focus lens 5 (focus position), and the vertical axis indicates the AF evaluation value. The focus position where the AF evaluation value reaches the maximum (peak value) is the focus position. However, in practice, if the focal point falls within the allowable circle of confusion, it can be regarded as in-focus, so that the in-focus position has a certain range.

  When a sufficiently bright and high-contrast subject is photographed, the AF evaluation value becomes a high sharpness curve (AF evaluation curve) as shown in FIG. 6, and the focus position is narrow. However, if the amount of light of the subject is insufficient or the contrast is low, the AF evaluation curve becomes a gentle mountain shape, that is, a curve with low sharpness as shown in FIG.

  When performing the flange back adjustment, if the in-focus position obtained in step 2 and step 5 in FIG. 3 is an in-focus position with respect to a subject from which an AF evaluation curve having a high sharpness as shown in FIG. The back adjustment value can be obtained with a small error. However, as shown in FIG. 7, if the focus position is for a subject that can obtain only an AF evaluation curve with a low sharpness, the focus position itself may include an error that cannot be ignored. The adjustment value also includes an error component. For this reason, even if the flange back adjustment operation is normally completed, there is a possibility that the adjustment is not actually performed correctly.

  However, conventionally, there has been no means for evaluating the reliability indicating whether or not the flange back adjustment has been performed accurately. If the reliability is known, when it is low, the subject can be changed and the flange back adjustment can be performed again to reduce the error as much as possible.

  Therefore, in this embodiment, the AF evaluation curve for the focus position is displayed on the display unit 61 in the adjustment mode (including during the flange back adjustment operation and after the adjustment operation is completed). By viewing this display, the user can easily confirm the reliability of the flange back adjustment.

  The display data for displaying the AF evaluation curve on the display unit 61 is created by the camera microcomputer 29. The display data is created as bitmap pattern data and output to the bitmap memory 31. The bitmap generation circuit 32 reads this bitmap pattern data from the bitmap memory 31, converts it into an analog video signal, and outputs it to the video superimposing circuit 33. Then, it is superimposed on the video signal by the video superimposing circuit 33 and output to the display unit 61.

  In the present embodiment, a case where an AF evaluation curve is displayed on the display unit 61 provided in the camera 34 will be described, but the present invention is not limited to this. For example, the bitmap pattern data may be output to the personal computer PC via a PC connector (USB connector or the like) 62 provided on the camera 34, and an AF evaluation curve may be displayed on the PC screen.

  FIG. 8 shows the procedure of the flange back adjustment operation including the AF evaluation curve display operation in this embodiment.

  When the adjustment mode is selected by the mode switch 63, the camera microcomputer 29 enters the adjustment mode. When the user selects AF adjustment on the menu screen for flange back adjustment, the camera microcomputer 29 first moves the variator lens 2 to the TELE end in step 101. Next, in step 102, an AF command is transmitted to the lens microcomputer 10, and the focus lens 5 is moved by focus control using the AF evaluation value by the AF control unit 10b.

  In step 103, the AF evaluation values during the focus control are sequentially acquired and displayed on the display unit 61 so as to draw an AF evaluation curve.

  In step 104, the lens microcomputer 10 determines whether or not the AF evaluation value at that time is the maximum, and if it does not reach the maximum value, continues the focus control. The screen of the display unit 61 at this time is shown in FIG. In FIG. 9, the position (vertical line) of the focus lens 5 in the focus control at the tele end and the AF evaluation curve in a predetermined range including the current focus position are displayed in a graph. This display shows the user intuitively understand the relationship between the focus position and the AF evaluation value.

  In the present embodiment, the case where the AF evaluation curve is displayed in a graph will be described. However, as other display forms, figures, characters (numerical values), etc., which show the relationship between the focus position and the AF evaluation value, are used. You may make it display.

  When the AF control unit 10b determines that the AF evaluation value is the maximum (in-focus), the camera microcomputer 29 determines in step 105 that the focus lens 5 remains at the in-focus position at the TELE end. The variator lens 2 is moved. In step 106, the focus position f1 at the TELE end is read.

  Next, in step 107, the camera microcomputer 29 transmits an AF command to the lens microcomputer 10, and moves the focus lens 5 by focus control using the AF evaluation value by the AF control unit 10b.

  In step 108, AF evaluation values during the focus control are sequentially acquired and displayed on the display unit 61 so as to draw an AF evaluation curve. The AF evaluation curve at this time is displayed in a different area from the AF evaluation curve at the TELE end.

  In step 109, the lens microcomputer 10 determines whether or not the AF evaluation value at that time is the maximum, and if it does not reach the maximum value, continues the focus control. When the AF evaluation value reaches the maximum value (in-focus), in step 110, the focus position f2 at the WIDE end is read. The screen of the display unit 61 at this time is shown in FIG.

  Further, in step 111, the user confirms the relationship between the position (f1) of the focus lens 5 at the TELE end and the AF evaluation curve, and the position (f2) of the focus lens 5 at the WIDE end and the AF evaluation curve. And determine whether readjustment is necessary. For example, when the focus position (vertical line) brought into focus by the focus control of the AF control unit 10b at the TELE end or the WIDE end is deviated from the truly maximum position on the AF evaluation curve. Need readjustment. In this case, for example, the subject is changed and “readjustment” on the display screen is selected by the user, so that the camera microcomputer 29 performs the flange back adjustment again.

  In this way, when the focus focus position substantially coincides with the position that is truly maximum on the AF evaluation curve, when the user selects “END” on the display screen, the process proceeds to step 112. In step 112, the camera microcomputer 29 calculates an adjustment value of the flange back using the AF evaluation value displayed in the graph at this time. Further, in step 113, as described in step 8 of FIG. 3, the adjustment value is corrected by a temperature change, a final flange back adjustment value is obtained, and this operation is terminated.

  In the first embodiment, the case where the AF evaluation curve is displayed has been described, but instead of displaying the AF evaluation curve, the reliability of the flange back adjustment is calculated, and when the reliability falls below a predetermined threshold value, the AF evaluation curve is displayed again. A warning message for prompting adjustment may be displayed on the display screen. In other words, the reliability of the flange back adjustment is also the reliability of the focus control of the AF control unit 10b.

  FIG. 11 shows the procedure of the flange back adjustment operation of this embodiment.

  When the adjustment mode is selected by the mode switch 63, the camera microcomputer 29 enters the adjustment mode. When the user selects AF adjustment on the menu screen for flange back adjustment, the camera microcomputer 29 first moves the variator lens 2 to the TELE end in step 201. Next, in step 202, an AF command is transmitted to the lens microcomputer 10, and the focus lens 5 is moved by focus control using the AF evaluation value by the AF control unit 10b.

  In step 203, the lens microcomputer 10 determines whether or not the AF evaluation value at that time is the maximum, and if it does not reach the maximum value, continues the focus control.

  When the AF control unit 10b determines that the AF evaluation value is the maximum (in-focus), the camera microcomputer 29 determines in step 204 that the focus lens 5 remains at the in-focus position at the TELE end. The variator lens 2 is moved. In step 205, the focus position f1 at the TELE end is read.

  Next, in step 206, the camera microcomputer 29 transmits an AF command to the lens microcomputer 10, and moves the focus lens 5 by focus control using the AF evaluation value by the AF control unit 10b.

  In step 207, the lens microcomputer 10 determines whether or not the AF evaluation value at that time is the maximum, and if it does not reach the maximum value, continues the focus control. When the AF evaluation value reaches the maximum value (focuss), in step 208, the focus position f2 at the WIDE end is read. A display screen while steps 201 to 208 are being executed is shown in FIG. Note that the AF evaluation curve described in the first embodiment may be displayed on this screen.

  In step 209, the camera microcomputer 29 calculates the reliability of the focus position at the TELE end. This calculation method will be described later.

  In step 210, if the calculated reliability exceeds a predetermined threshold (that is, if a predetermined reliability condition is satisfied), then in step 211, the reliability of the focus position at the WIDE end is calculated. To do.

  In step 212, if the calculated reliability exceeds a predetermined threshold value, the display unit 61 displays that the flange back adjustment has been completed normally, as shown in FIG. Then, the process proceeds to Step 215.

  On the other hand, when the reliability of the focus position at the TELE end or the WIDE end falls below a predetermined threshold in Step 210 or Step 212 (that is, when a predetermined reliability condition is not satisfied), readjustment is performed as shown in FIG. Displays a warning message prompting Instead of displaying the warning message, a warning sound may be generated from a speaker (not shown) provided in the camera 34.

  Next, in Step 214, the camera microcomputer 29 performs the flange back adjustment again by selecting “Readjustment” on the display screen by the user who changed the subject. Thus, when the reliability of the focus position exceeds a predetermined threshold value, the screen shown in FIG. 13 is displayed on the display unit 61. Then, the process proceeds to Step 215.

  In step 215, the camera microcomputer 29 calculates the adjustment value of the flange back using the AF evaluation value at this time. Further, in step 216, as described in step 8 of FIG. 3, the adjustment value is corrected by a temperature change to obtain a final flange back adjustment value, and this operation is terminated.

  Hereinafter, the reliability calculation method described above will be described. The reliability in the present embodiment indicates how much the focus control of the AF control unit 10b is performed based on the AF evaluation value with a high degree of sharpness.

  The most basic reliability is obtained by the reciprocal of the standard deviation. The standard deviation is a value representing the degree of data dispersion. As shown in FIG. 15, the standard deviation is a value represented by adding the square value of the difference between the average value of all data and each data, averaging it, and taking the square root of the average value. .

  The standard deviation becomes smaller as the data sharpness becomes higher as shown in FIG. 6, and becomes larger as the sharpness becomes lower as shown in FIG. As a result of the focus control, it is considered that the higher the sharpness of the AF evaluation curve, the higher the reliability. Therefore, a value obtained by taking the reciprocal of the standard deviation of the AF evaluation curve can be regarded as the reliability of the focus position by the focus control.

  In each of the above embodiments, the case where the AF evaluation curve is displayed or the reliability of the focus position is determined in the flange back adjustment has been described. However, the display of these AF evaluation curves and the determination of the reliability of the focus position can be used other than the flange back adjustment. For example, it can be used to check whether or not focus control is executed with high accuracy in normal shooting.

1 is a block diagram showing a configuration of a camera system including a video camera that is Embodiment 1 of the present invention. FIG. 3 is a diagram illustrating a menu screen in the video camera according to the first embodiment. The flowchart which shows the basic procedure of a flange back adjustment method. FIG. 4 is a diagram illustrating lens cam data (design data) according to the first exemplary embodiment. FIG. 4 is a diagram illustrating lens cam data (corrected data) according to the first exemplary embodiment. The figure which shows the tolerance | permissible_range of the focusing focus position with respect to AF evaluation curve. The figure which shows the tolerance | permissible_range of the focusing focus position with respect to AF evaluation curve. 9 is a flowchart illustrating a procedure of a flange back adjustment operation for performing an AF evaluation curve display operation in the first embodiment. 6 is a diagram illustrating a display screen during focus adjustment at a TELE end in Embodiment 1. FIG. The figure which shows the display screen at the time of completion | finish of the flange back adjustment in Example 1. FIG. It is Example 2 of this invention, Comprising: The flowchart which shows the procedure of the flange back adjustment operation which performs reliability calculation. The figure which shows the display screen in the flange back adjustment in Example 2. FIG. The figure which shows the display screen at the time of completion | finish of flange back adjustment in Example 2. FIG. The figure which shows the display screen at the time of completion | finish of flange back adjustment in Example 2. FIG. The figure which shows the calculation formula of a standard deviation.

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 Variator lens 5 Focus lens 10 Lens microcomputer 12 Interchangeable lens 21, 22, 23 Image pick-up element 24 Temperature detection element 28 Camera signal processing circuit 29 Camera microcomputer 31 Bitmap memory 32 Bitmap generation circuit 33 Video superimposition circuit 34 Video camera 61 Display unit 62 Connector for PC connection 63 Mode selector switch

Claims (10)

An imaging device to which an interchangeable lens is attached,
Evaluation value generating means for generating a focus evaluation value representing a focus state from a video signal obtained by using an image sensor;
An image pickup apparatus comprising: a display signal generating unit configured to generate a display signal for displaying information indicating a relationship between a position of a focus lens provided in the interchangeable lens and the focus evaluation value.   The display signal generating means displays the display signal for displaying information indicating a relationship between the focus lens position and the focus evaluation value in a state where focus is obtained by focus control performed in the interchangeable lens. The imaging apparatus according to claim 1, wherein: An adjustment mode for performing flange back adjustment on the interchangeable lens;
The imaging apparatus according to claim 1, wherein the display signal generation unit generates the display signal in the adjustment mode.   The imaging apparatus according to claim 1, wherein the display signal is a signal that enables display by a graph, a figure, or characters.   5. The imaging apparatus according to claim 1, further comprising a display unit configured to display information indicating a relationship between a position of the focus lens and the focus evaluation value based on the display signal. . An imaging device to which an interchangeable lens is attached,
Evaluation value generating means for generating a focus evaluation value representing a focus state from a video signal obtained by using an image sensor;
An image pickup apparatus comprising: a determination unit that determines whether or not the focus evaluation value satisfies a predetermined reliability condition in a state where focus is obtained by focus control performed in the interchangeable lens.   The imaging apparatus according to claim 6, further comprising a warning unit that outputs a warning signal when the focus evaluation value does not satisfy the predetermined reliability condition. An adjustment mode for performing flange back adjustment on the interchangeable lens;
The imaging apparatus according to claim 6, wherein the determination unit performs the determination in the adjustment mode.   The imaging apparatus according to claim 7, wherein the warning signal is a signal for performing display or audio output. An imaging device according to any one of claims 1 to 9,
An imaging system comprising: an interchangeable lens attached to the imaging device.