JP2008096582A - Camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means for checking the state of a field of a wider range than a photographing optical system and a photographing range of a photographing part while keeping an eye on an optical finder. <P>SOLUTION: A camera is provided with a first imaging part for photographing recording images, a finder optical system, a second imaging part, a display part, and a control part. The finder optical system has an eyepiece for observing optical images of an object by a light flux from a photographing optical path of the first imaging part. The second imaging part photographs a view field checking image from an optical path different from the first imaging part. A display processing part carries out field angle display processing indicating a range of a field angle of the first imaging part in a view field checking image. The display part presents the view field checking image processed by field angle display on the eyepiece. The control part switches a first state presenting optical images on the eyepiece and a second state presenting the view field checking image on the eyepiece. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a camera having a viewfinder suitable for telephoto shooting and the like.

Conventionally, in a digital camera, it is possible to display an image being shot on a display device such as a liquid crystal monitor and determine a shooting composition. In particular, in a video camera, a camera provided with an auxiliary photographing unit for photographing a wide-angle image for finder display is known in addition to a recording imaging unit. Patent Document 1 is shown as an example of the above camera.
JP-A-5-145818

  Incidentally, a conventional single-lens reflex camera has a TTL (Through The Lens) type optical viewfinder that observes an image of a subject with reflected light from a movable mirror arranged in a photographing optical path. Such an optical finder can confirm the state of the subject through the photographing optical system as it is, and the range of the field of view by the optical finder substantially coincides with the angle of view of the photographing optical system. Therefore, especially when the angle of view of the photographing optical system is narrow as in telephoto shooting, there is room for improvement in that the user easily loses sight of the moving subject and misses a photo opportunity.

  The present invention has been made in view of the above problems of the prior art. An object of the present invention is to provide a means capable of confirming a wider range of the state of the field of view and an imaging range of an imaging unit than an imaging optical system without taking an eye off the optical viewfinder.

  A camera according to a first aspect includes a first imaging unit that captures an image for recording, a finder optical system, a second imaging unit, a display unit, and a control unit. The viewfinder optical system has an eyepiece that can observe an optical image of a subject by a light beam from a photographing optical path of the first imaging unit. The second imaging unit captures a visual field confirmation image from an optical path different from that of the first imaging unit. The display processing unit performs an angle of view display process that indicates a range of the angle of view of the first imaging unit in the visual field confirmation image. The display unit presents the visual field confirmation image subjected to the view angle display process to the eyepiece unit. The control unit switches between a first state in which an optical image is presented to the eyepiece and a second state in which a visual field confirmation image is presented to the eyepiece.

  The second invention is a camera to which an external camera unit can be attached. This camera includes an attachment unit for connecting camera units, an imaging unit that captures an image for recording, a finder optical system, a communication unit, a display processing unit, a display unit, and a control unit. The viewfinder optical system has an eyepiece that can observe an optical image of a subject by a light beam from a photographing optical path of the imaging unit. The communication unit receives from the camera unit a field-of-view confirmation image taken on a different optical path from the imaging unit. The display processing unit performs an angle of view display process that indicates a range of an angle of view of the imaging unit in the visual field confirmation image. The display unit presents the visual field confirmation image subjected to the view angle display process to the eyepiece unit. The control unit switches between a first state in which an optical image is presented to the eyepiece and a second state in which a visual field confirmation image is presented to the eyepiece.

In a third aspect based on the first aspect or the second aspect, the display processing unit superimposes a frame indicating a field angle range on the visual field confirmation image.
In a fourth aspect based on the third aspect, the display processing unit changes the display color of the frame based on at least one of luminance and hue of the visual field confirmation image.
In a fifth aspect based on the first or second aspect, the display processing unit makes the display of the visual field confirmation image different between the inside and the outside of the angle of view.

In a sixth aspect based on the fifth aspect, the display processing unit performs image processing using a smoothing filter or a contour extraction filter on a portion corresponding to the outside of the angle of view in the data of the visual field confirmation image.
In a seventh aspect based on the fifth aspect, the display processing unit displays the inside of the angle of view in color in the visual field confirmation image, and displays the outside of the angle of view in black and white.

In an eighth aspect based on the fifth aspect, the display processing section performs image processing for distorting a portion corresponding to the outside of the angle of view of the visual field confirmation image.
In a ninth aspect based on the fifth aspect, the display processing unit reduces the luminance outside the angle of view in the visual field confirmation image to be lower than that inside the angle of view.
In a tenth aspect based on the fifth aspect, the display processing section performs image processing for lowering the resolution than the image inside the angle of view in a portion corresponding to the outside of the angle of view in the data of the visual field confirmation image. Apply.

In an eleventh aspect based on the first or second aspect, the camera further includes a mount portion. The mount unit is detachable from the interchangeable lens, and acquires angle-of-view information related to the angle of view from the interchangeable lens. The display processing unit stops the view angle display process in the second state when the view angle information cannot be acquired.
In a twelfth aspect based on the first or second aspect, the camera further includes a mount portion. The mount unit is detachable from the interchangeable lens, and acquires angle-of-view information related to the angle of view from the interchangeable lens. The display processing unit displays an error display on the display unit in the second state when the angle of view information cannot be acquired.

  According to the present invention, a user can confirm a field-of-view confirmation image photographed in an optical path different from the photographing optical path of the recording image in the eyepiece portion of the finder optical system. In addition, the field-of-view confirmation image shows the range of the angle of view of the imaging unit that captures the recording image.

(Description of the first embodiment)
Hereinafter, the configuration of the single-lens reflex electronic camera according to the first embodiment will be described with reference to the drawings.
FIG. 1 is a diagram illustrating a photographing mechanism of the electronic camera in the first embodiment. FIG. 2 is a front view of the camera body in the first embodiment. The electronic camera according to the first embodiment includes a camera body 11 and a lens unit 12 that houses a photographing optical system.

  The camera body 11 and the lens unit 12 are provided with a pair of mounts 13 and 14 that form a male-female relationship. The lens unit 12 is exchangeably attached to the camera body 11 by coupling the lens side mount 14 to the camera side mount 13 by a bayonet mechanism or the like. The mounts 13 and 14 are each provided with an electrical contact (not shown). When the camera body 11 and the lens unit 12 are connected, electrical connection between the two is established by contact between the electrical contacts.

  First, the configuration of the lens unit 12 will be described. The lens unit 12 includes a zoom lens 15, a zoom encoder 15a, a focus lens 16, a lens driving unit 16a, a diaphragm 17, a diaphragm driving unit 17a, and a lens microcomputer 18. The zoom encoder 15a, the lens driving unit 16a, and the aperture driving unit 17a are each connected to the lens microcomputer 18.

The zoom lens 15 is a lens for adjusting the focal length, and is configured to be movable back and forth in the optical axis direction in accordance with an operation of a zoom ring (not shown). The zoom lens 15 is attached with a zoom encoder 15a for detecting the position of the lens in the optical axis direction.
The focus lens 16 is a lens for adjusting the in-focus position, and is configured to be movable back and forth in the optical axis direction. The lens driving unit 16 a drives the focus lens 16 by a motor (not shown) and outputs the position of the focus lens 16 in the optical axis direction to the lens microcomputer 18.

The diaphragm 17 adjusts the amount of light incident on the camera body 11 by opening and closing the diaphragm blades. The aperture drive unit 17a controls the aperture of the aperture 17 with a motor (not shown).
The lens microcomputer 18 communicates with the camera body 11 through the electrical contacts of the mount 14 and executes various controls in the lens unit 12. The lens microcomputer 18 transmits lens data and the like recorded in a ROM (not shown) to the camera body 11.

Incidentally, the lens unit 12 shown in FIG. 1 is merely an example of a configuration of a general zoom lens unit. Therefore, in addition to the lens unit 12 described above, for example, a lens unit that does not include the lens microcomputer 18 or a single-focus lens unit can be attached to the camera body 11 of the first embodiment.
Next, the configuration of the photographing mechanism of the camera body 11 will be described. The camera body 11 includes a main mirror 21, a mechanical shutter 22, a first image sensor 23, a sub mirror 24, a focus detection unit 25, a finder optical system (32 to 35), a photometry unit 26, and a superimposition. Part (SI part) 27, finder monitor 28, interchangeable lens 29, and second image sensor 30.

  The main mirror 21, the mechanical shutter 22, and the first image sensor 23 are arranged along the optical axis of the photographing optical system. A sub mirror 24 is disposed behind the main mirror 21. In addition, a finder optical system, a photometry unit 26, an SI unit 27, a finder monitor 28, a lens 29, and a second image sensor 30 are arranged on the upper portion of the camera body 11. Further, a focus detection unit 25 is disposed in the lower region of the camera body 11. A hot shoe 31 for attaching a flash light emitting device or the like is provided on the upper portion of the camera body 11.

  The main mirror 21 is pivotally supported by a rotation shaft (not shown) and can be switched between an observation state and a retracted state. The main mirror 21 in the observation state is inclined and arranged in front of the mechanical shutter 22 and the first image sensor 23. The main mirror 21 in the observation state reflects the light beam that has passed through the photographing optical system upward and guides it to the finder optical system. The central portion of the main mirror 21 is a half mirror. A part of the light beam transmitted through the main mirror 21 is refracted downward by the sub mirror 24 and guided to the focus detection unit 25. The focus detection unit 25 detects an image shift amount of a subject image divided by a separator lens (not shown) for each AF area, and performs so-called phase difference detection type focus detection.

On the other hand, the retracted main mirror 21 is flipped upward together with the sub mirror 24 and is at a position off the photographing optical path. When the main mirror 21 is in the retracted state, the light beam that has passed through the photographing optical system is guided to the mechanical shutter 22 and the first image sensor 23.
The finder optical system has a diffusion screen (focus plate) 32, a condenser lens 33, a pentaprism 34, and an eyepiece lens 35. Of the optical elements of the finder optical system, the pentaprism 34 is housed in the position of the projecting portion 11 a of the camera body 11.

The diffusing screen 32 is positioned above the main mirror 21, and the light beam reflected by the main mirror 21 in the observation state is once imaged. The light beam formed on the diffusing screen 32 passes through the condenser lens 33 and the pentaprism 34, and is 90 to the incident surface of the pentaprism 34.
Guided to an exit surface having an angle of °. Then, the light beam from the exit surface of the pentaprism 34 reaches the eyes of the user via the eyepiece lens 35. The surface facing the exit surface of the pentaprism 34 is a half mirror.

The photometry unit 26 has a light receiving surface in which light receiving elements are two-dimensionally arranged. The photometric unit 26 can re-image a part of the light beam imaged on the diffusion screen 32 on the light receiving surface, and divide the photographing screen into a plurality of light beams by the light beam that has passed through the photographing optical system so that photometry can be performed. The photometry unit 26 is disposed in the vicinity of the pentaprism 34.
The SI unit 27 irradiates the diffusion screen 32 with illumination light, thereby performing superimpose display (SI display) in which the position of the AF area at the time of shooting is superimposed on the optical image of the finder optical system.

The in-viewfinder monitor 28 is disposed so as to be opposed to the half mirror surface (the surface facing the exit surface) of the pentaprism 34. A visual field confirmation image, which will be described later, is displayed on the finder monitor 28.
The lens 29 is exposed to the outside of the camera body 11 and is attached to the lens mounting portion 29a of the camera body 11 so as to be replaceable. The second image sensor 30 directly captures an image of the subject via the lens 29. The second image sensor 30 can photograph the subject from an optical path different from that of the first image sensor 23 that performs photographing with the light flux that has passed through the lens unit 12. Note that the angle of view of the lens 29 is set to be wider than the angle of view of the lens unit 12.

  Further, the lens 29 and the second image sensor 30 of the first embodiment are housed in the protruding portion 11 a of the camera body 11. As shown in FIG. 2, the projecting portion 11 a of the camera body 11 is formed in a shape projecting upward from the camera body 11 at a substantially middle position on the upper surface side of the camera body 11. That is, since the positions of the lens 29 and the second image sensor 30 are away from the position of the mount 13 of the camera body 11, there is less possibility that the luminous flux from the subject is blocked by the lens barrel of the lens unit 12 and vignetting occurs.

Here, in the first embodiment, the following description is given on the assumption that a lens 29 having an optical zoom function and an AF function is attached to the lens attachment portion 29a. Note that the zoom mechanism and AF mechanism in the lens 29 are basically the same as those in the lens unit 12, and a duplicate description thereof will be omitted. In FIG. 1, the lens 29 is shown as a single lens for simplicity.
Next, the circuit configuration of the electronic camera will be described. FIG. 3 is a block diagram of the camera body of the first embodiment. The camera main body 11 includes a first imaging unit 41, a second imaging unit 42, a memory 43, a recording I / F 44, a display, in addition to the focus detection unit 25, the photometry unit 26, the SI unit 27, and the in-finder monitor 28. An I / F 45, a main monitor 46, an external I / F 47, an operation unit 48, a power supply unit 49, a CPU 50 and a system bus 51 are included. Here, the first imaging unit 41, the memory 43, the recording I / F 44, the display I / F 45, the external I / F 47 and the CPU 50 are connected via a system bus 51. The CPU 50 is also connected to the electrical contact of the mount 13 and the electrical contact of the hot shoe 31 (the illustration thereof is omitted in FIG. 3).

The first imaging unit 41 includes a first imaging element 23, a first analog processing unit 41a, and a first digital processing unit 41b.
The first image sensor 23 is a sensor for generating a main image that is a recording image. The first image sensor 23 photoelectrically converts the light beam that has passed through the lens unit 12 at the time of release, and outputs an analog image signal of the main image. The output signal of the first image sensor 23 is input to the first analog processing unit 41a. Note that the first image sensor 23 can also output a through image by thinning out at predetermined intervals during shooting standby (non-release). Therefore, the main mirror 21
Can be determined by the CPU 50 based on the through image of the first image sensor 23.

  The first analog processing unit 41a is an analog front end circuit having a CDS circuit, a gain circuit, an A / D conversion circuit, and the like. The CDS circuit reduces the noise component of the output of the first image sensor 23 by correlated double sampling. The gain circuit amplifies the gain of the input signal and outputs it. In this gain circuit, the imaging sensitivity corresponding to the ISO sensitivity can be adjusted. The A / D conversion circuit performs A / D conversion of the output signal of the first image sensor 23. In FIG. 3, illustration of each circuit of the first analog processing unit 41a is omitted.

  The first digital processing unit 41b performs various kinds of image processing (defective pixel correction, color interpolation, gradation conversion processing, white balance adjustment, edge enhancement, etc.) on the output signal of the first analog processing unit 41a. Generate image data. The first digital processing unit 41a also executes compression / decompression processing of the data of the main image. The first digital processing unit 41 a is connected to the system bus 51.

The second imaging unit 42 includes a second imaging element 30, a second analog processing unit 42a, and a second digital processing unit 42b. Since the configuration of the second imaging unit 42 substantially corresponds to the configuration of the first imaging unit 41, a part of the description of the overlapping portion of both is omitted.
The second image sensor 30 captures a field-of-view confirmation image for the viewfinder. The second image sensor 30 photoelectrically converts the subject image formed through the lens 29 at predetermined intervals and outputs a through image (field-of-view confirmation image). The output signal of the second image sensor 30 is input to the second analog processing unit 42a.

The second analog processing unit 42a is an analog front end circuit having a CDS circuit, a gain circuit, an A / D conversion circuit, and the like. The second digital processing unit 42b executes a color interpolation process for the through image. The through image data output from the second digital processing unit 42 b is input to the CPU 50.
The memory 43 is a buffer memory for temporarily recording the data of the main image in the pre-process and post-process of the image processing by the first digital processing unit 41b.

  A connector for connecting the recording medium 52 is formed in the recording I / F 44. The recording I / F 44 executes writing / reading of captured image data with respect to the recording medium 52 connected to the connector. The recording medium 52 includes a hard disk, a memory card with a built-in semiconductor memory, or the like. In FIG. 3, a memory card is illustrated as an example of the recording medium 52.

  The display I / F 45 controls the display on the main monitor 46 based on an instruction from the CPU 50. The main monitor 46 is disposed, for example, on the back surface of the camera body 11. The main monitor 46 displays various images according to instructions from the CPU 50 and the display I / F 45. For example, the main monitor 46 can display a reproduction image of the main image, a menu screen that can be input in a GUI (Graphical User Interface) format, and the like (illustration of each image is omitted).

The external I / F 47 has a connection terminal of a serial communication standard such as USB (Universal Serial Bus). The external I / F 47 controls data transmission / reception with a computer or the like connected via the connection terminal in accordance with the communication standard.
The operation unit 48 includes a plurality of switches that accept user operations. For example, the operation unit 48 includes a release button 48a, a mode dial 48b, a wide preview button 48c, an aperture preview button 48d, and a zoom switch 48e.

  The release button 48a receives from the user an instruction input for starting an AF operation before photographing and an instruction input for starting an exposure operation during photographing. The mode dial 48b receives an input for switching the shooting mode from the user. The wide preview button 48c accepts a switching operation between a finder display of an optical image by the finder optical system and a display of a visual field confirmation image (wide preview display) by the finder monitor 28 from the user. The aperture preview button 48d accepts a confirmation input from the user for confirming the range of the depth of field. When the confirmation input is made, the diaphragm 17 is narrowed down, and the user can confirm the range of the depth of field with the finder optical system. The zoom switch 48e accepts an operation for optically or electronically enlarging / reducing the magnification of the visual field confirmation image from the user.

The power supply unit 49 supplies battery power (not shown) to each part of the camera body 11. The power supply unit 49 detects the remaining battery level based on the battery voltage.
The CPU 50 performs overall control of each part of the electronic camera. The CPU 50 functions as a sequence control unit 50a, a shooting setting unit 50b, a display processing unit 50c, and a face detection unit 50d by a program stored in a ROM (not shown).

  The sequence control unit 50a performs control of operations of the lens unit 12, the main mirror 21, the mechanical shutter 22, the first imaging unit 41, the second imaging unit 42, and the like. Further, the sequence control unit 50a executes control for switching between finder display by the finder optical system and wide preview display in accordance with the operation of the wide preview button 48c. The sequence control unit 50a also functions as a light emission control unit that performs light emission control of an external flash light emitting device (not shown).

The shooting setting unit 50b performs autofocus (AF), automatic exposure (AE) calculation, auto white balance (AWB) calculation, and the like, and various parameters (exposure time, aperture) of the first imaging unit 41 Value, imaging sensitivity, etc.). The shooting setting unit 50b also bears processing related to AF, AE, and AWB of the second imaging unit 42.
More specifically, the shooting setting unit 50b calculates the defocus amount (shift amount and shift direction from the in-focus position) of the focus lens 16 for each AF area based on the image shift amount of the focus detection unit 25. . In addition, the photographing setting unit 50 b performs AE calculation and AWB calculation based on the output of the photometry unit 26. Note that the shooting setting unit 50b can also execute each calculation of AF, AE, and AWB based on the through image data of the first image sensor 23 or the second image sensor 30.

The display processing unit 50c performs various types of image processing on the through image data of the second imaging unit 42. The visual field confirmation image output from the display processing unit 50c is displayed on the finder monitor 28.
The face detection unit 50d performs a known face detection process on the through image data of the second imaging unit 42 to detect the face area of the subject included in the visual field confirmation image. For example, the face detection unit 50d extracts a face area by a facial feature point extraction process described in Japanese Patent Laid-Open No. 2001-16573. Examples of the feature points include eyebrow, eye, nose, and lip end points, face contour points, head apexes, and chin lower end points. Alternatively, as disclosed in Japanese Patent Laid-Open No. 8-63597, the face detection unit 50d detects the contour of the skin color area based on the color information of the subject, and further detects the face by matching with a template of face parts prepared in advance. May be.

The operation of the electronic camera related to the wide preview display in the first embodiment will be described below with reference to the flowchart of FIG.
Step 101: When the user turns on the power of the camera body 11, the CPU 50 starts supplying power to the second image sensor 30. At the stage of S101, the main mirror 21 is at the observation position. Therefore, the user can observe the subject image by the light flux that has passed through the lens unit 12 from the eyepiece lens 35. FIG. 5 shows a display state of an optical image of a subject in the finder optical system.

Step 102: The CPU 50 determines whether or not the wide preview button 48c is pressed. When the wide preview button 48c is pressed (YES side), the process proceeds to S103. On the other hand, when the wide preview button 48c is not pressed (NO side), the process proceeds to S123.
Step 103: The CPU 50 determines whether or not the SI unit 27 is performing SI display of the AF area when the wide preview button 48c is pressed. When SI display is being performed (YES side), the process proceeds to S104. On the other hand, when the SI display is not performed (NO side), the process proceeds to S105.

Step 104: The CPU 50 instructs the SI unit 27 to stop SI display. This is because in the wide preview display, an optical image by the finder optical system is not displayed and SI display is not necessary.
Step 105: The CPU 50 performs a shooting condition setting operation. Specifically, the CPU 50 executes AF based on the output of the focus detection unit 25. Further, the CPU 50 performs AE calculation and AWB calculation based on the output of the photometry unit 26. In S105, the SI display of the AF area by the SI unit 27 is not performed.

Step 106: The CPU 50 executes wide preview determination control to determine whether or not the wide preview display is prohibited.
Specifically, the CPU 50 displays a wide preview display when any of the following conditions is satisfied: (1) when the flash light emitting device emits light at the time of shooting, or (2) when the luminance of the object scene is equal to or less than the threshold value. Set the prohibited flag to on.

Step 107: The CPU 50 determines whether or not a flag for prohibiting wide preview display is set to ON in the wide preview determination control (S106). When the wide preview display is prohibited (YES side), the process proceeds to S123. On the other hand, if wide preview display is permitted (NO side), the process proceeds to S108.
Step 108: The CPU 50 stops the operations of the focus detection unit 25 and the photometry unit 26 before starting the wide preview display. This is because during the wide preview display, the focus detection unit 25 and the photometry unit 26 cannot function due to a light shielding operation described later.

Step 109: The CPU 50 executes a light blocking operation for cutting incident light from the lens unit 12 to the finder optical system.
Specifically, the CPU 50 moves the main mirror 21 from the observation position to the retracted position, and cuts incident light to the finder optical system. If the luminance of the object scene is sufficiently low, the CPU 50 may cut the incident light to the finder optical system by narrowing the diaphragm 17.

Step 110: The CPU 50 acquires lens information (such as the lens positions of the zoom lens 15 and the focus lens 16) from the lens unit 12.
Step 111: The CPU 50 executes AF of the lens 29 based on the lens position of the focus lens 16 in the lens information of S110. If the lens 29 is pan focus and does not have an AF function, the step of S111 is omitted.

Step 112: The CPU 50 performs an initial setting of the AE and AWB of the second imaging unit 42 based on the shooting conditions acquired in S105. After the second imaging unit 42 starts imaging, the CPU 50 adjusts the AE and AWB parameters of the second imaging unit 42 based on the through image data of the second imaging unit 42.
Step 113: The CPU 50 captures a field-of-view confirmation image by the second image sensor 30 of the second imaging unit 42. Then, the second imaging unit 42 outputs the visual field confirmation image data to the CPU 50.

Step 114: The display processing unit 50c of the CPU 50 displays the visual field confirmation image on the finder monitor 28. Since the angle of view of the lens 29 is wider than the angle of view of the lens unit 12, it is possible to display a wider range of subjects in the field-of-view confirmation image than in the optical image of the finder optical system.
Further, FIG. 6 shows the state of the camera body 11 when the wide preview is displayed in S114. In the wide preview display, since the incident light from the lens unit 12 to the finder optical system is cut by the light shielding operation (S109), the user can observe only the visual field confirmation image of the finder monitor 28 from the eyepiece 35. it can. Therefore, the user can observe the scene with a field-of-view confirmation image having a wider angle than the viewfinder optical system without taking his eyes off the eyepiece lens 35. FIG. 6 shows an example in which the main mirror 21 is moved to the retracted position during the light shielding operation so as to be in a light shielding state.

Further, the display processing unit 50c in S114 executes an angle-of-view display process that shows the range of the angle of view of the first imaging unit 41 on the visual field confirmation image.
Specifically, first, the display processing unit 50c calculates the range of the angle of view of the first imaging unit 41 in the visual field confirmation image based on the lens information (S110) and the zoom position data of the lens 29.

  Here, when the lens information cannot be acquired from the lens unit 12 as in the case where the old lens unit 12 having no lens-camera communication function is attached to the camera body 11, the display processing unit 50c performs the first imaging. The range of the angle of view of the part 41 cannot be calculated. Therefore, when the lens information cannot be acquired as described above, the display processing unit 50c stops the view angle display process. That is, the display processing unit 50c displays the field-of-view confirmation image captured by the second imaging unit 42 on the finder monitor 28 as it is, and omits the display of the field angle range of the first imaging unit 41. In addition, when the lens information cannot be acquired as described above, the display processing unit 50c may superimpose and display an error display indicating that the lens information cannot be acquired on the visual field confirmation image using the on-screen function. An example of the visual field confirmation image when the lens information cannot be acquired is shown in FIG. The visual field confirmation image in FIG. 7 corresponds to the scene in FIG. In the example of FIG. 7, the characters “no lens information” are displayed on the visual field confirmation image as the error display.

  Secondly, the display processing unit 50c performs processing (1) or (2) described later on the data of the visual field confirmation image based on the calculation result regarding the range of the angle of view described above. Then, the display processing unit 50c displays the visual field confirmation image after the view angle display processing on the in-finder monitor 28. When the lens information can be acquired from the lens unit 12, the display processing unit 50c may superimpose and display a display indicating the numerical value of the focal length of the lens unit 12 on the visual field confirmation image with an on-screen function (see FIG. 8). ).

  (1) The display processing unit 50c superimposes and displays the frame indicating the range of the angle of view on the field-of-view confirmation image using the on-screen function as the angle of view display process. An example of the visual field confirmation image in which the angle of view of the first imaging unit 41 is displayed in a frame is shown in FIG. The visual field confirmation image in FIG. 8 corresponds to the scene in FIG. According to the view angle display process (1), the user can clearly grasp the shooting range of the first imaging unit 41 by the frame display on the visual field confirmation image.

Here, in order to improve the visibility of the frame display, the display processing unit 50c preferably changes the display color of the frame display according to the luminance and hue of the visual field confirmation image.
First, changing the display color of the frame display by hue will be described. The display processing unit 50c generates a color histogram for each color of red, green, and blue of the visual field confirmation image, and determines the color tone of the visual field confirmation image from the color histogram. As an example, when the visual field confirmation image has many green color components and few red and blue color components, the display processing unit 50c determines that the color tone of the visual field confirmation image is green. Then, the display processing unit 50c determines a complementary color for the above color tone as a display color for frame display. As an example, if the color tone of the visual field confirmation image is green, the display processing unit 50c determines the display color of the frame display to be magenta.

  Next, the change of the display color of the frame display by luminance will be described. The display processing unit 50c generates a luminance histogram of the visual field confirmation image and determines the overall brightness of the visual field confirmation image from the luminance histogram. Then, the display processing unit 50c adjusts the brightness of the display color of the frame display according to the brightness of the visual field confirmation image. Specifically, when the visual field confirmation image is a bright scene, the display processing unit 50c reduces the brightness of the display color of the frame display. On the other hand, when the visual field confirmation image is a dark scene, the display processing unit 50c increases the brightness of the display color of the frame display.

(2) The display processing unit 50c performs display with different display modes of the visual field confirmation image inside and outside the range of the angle of view as the angle of view display process. Also in this case, the user can clearly grasp the imaging range of the first imaging unit 41 in the visual field confirmation image.
At this time, the display processing unit 50c displays the visual field confirmation image as it is inside the imaging range of the first imaging unit 41. On the other hand, the display processing unit 50c performs display in a state where visibility of the visual field confirmation image is lowered outside the imaging range of the first imaging unit 41 (see FIG. 9). Examples of the view angle display process in (2) include the following examples (a) to (f).

  (A) The display processing unit 50c performs a filtering process using a smoothing filter or a contour extraction filter on the data corresponding to the outside of the angle of view of the first imaging unit 41 in the visual field confirmation image data. To do. In the case of (a), in the view confirmation image of the in-viewfinder monitor 28, a normal image that has not been filtered is displayed as it is inside the angle of view of the first imaging unit 41. On the other hand, according to the image processing using the smoothing filter, the image is displayed out of focus with the outside of the angle of view of the first imaging unit 41, so that the identification is easy. Similarly, according to the image processing by the contour extraction filter, since only the contour of the image is highlighted outside the angle of view of the first imaging unit 41, it is easy to identify.

(B) The display processing unit 50c displays the range of the angle of view of the first imaging unit 41 in the visual field confirmation image in color, and displays the outside of the angle of view of the first imaging unit 41 in black and white. In the case of (b), in the visual field confirmation image of the in-viewfinder monitor 28, only the inside of the angle of view of the first imaging unit 41 is conspicuous in color display, so that it is easy to identify.
(C) The display processing unit 50 c makes the luminance outside the angle of view of the first imaging unit 41 in the visual field confirmation image lower than the inside of the angle of view of the first imaging unit 41. According to the case (c), in the field-of-view confirmation image of the in-viewfinder monitor 28, the inside of the angle of view of the first imaging unit 41 is displayed relatively brightly and is easily distinguished.

  (D) The display processing unit 50 c sets the resolution outside the angle of view of the first imaging unit 41 in the visual field confirmation image to be lower than the inside of the angle of view of the first imaging unit 41. The resolution outside the angle of view at this time is appropriately determined within a range in which the user can recognize the movement of the subject. According to the case of (d), in the field-of-view confirmation image of the in-viewfinder monitor 28, the outside of the angle of view of the first imaging unit 41 is a rough image, and the inside of the angle of view of the first imaging unit 41 is a fine and clear image. Therefore, it becomes easy to identify.

(E) The display processing unit 50c performs image processing for distorting the outside of the angle of view of the first imaging unit 41 in the visual field confirmation image.
As an example, the display processing unit 50c performs a geometric transformation process for adding distortion to a portion corresponding to the outside of the angle of view of the first imaging unit 41 in the data of the visual field confirmation image. Execute. This distortion may be either a barrel type in which the corners of the image shrink toward the inside, or a pincushion type in which the corners of the image extend toward the outside. Then, the display processing unit 50c displays a normal visual field confirmation image that is not subjected to the geometric conversion process as it is in the region where the inside of the view angle of the first imaging unit 41 is displayed on the in-finder monitor 28. On the other hand, the display processing unit 50c displays a distorted field-of-view confirmation image by adding distortion to an area in the finder monitor 28 that displays the outside of the angle of view of the first imaging unit 41.

  In FIG. 10A, an explanatory diagram in the case of applying barrel-shaped distortion outside the angle of view of the first imaging unit 41 is shown. In particular, in the case of barrel distortion, the image outside the angle of view of the first imaging unit 41 is distorted so as to be closer to the center than the original position. In other words, the in-viewfinder monitor 28 can display a wide range of the object scene as much as the image is distorted and shrunk. Therefore, the in-viewfinder monitor 28 can display a wider range of the scene than the normal display state as in the case where a fisheye lens is used.

  As another example, the display processing unit 50c has a geometry that shrinks and distorts the image in the vertical direction or the horizontal direction in a portion corresponding to the outside of the angle of view of the first imaging unit 41 in the data of the visual field confirmation image. A geometric conversion process may be performed. At this time, it is preferable that the display processing unit 50c increases the distortion of the image as the distance from the center increases. FIG. 10B is an explanatory diagram when the outside of the angle of view of the first imaging unit 41 is contracted in the horizontal direction. Even in this example, the in-viewfinder monitor 28 can display a wider range of field than the normal display state. Note that the case where the outside of the angle of view of the first imaging unit 41 is contracted in the vertical direction is substantially the same as in the case of FIG.

In the case of (e) described above, in the field-of-view confirmation image of the in-viewfinder monitor 28, the outside of the angle of view of the first imaging unit 41 is distorted and displayed, so that it is easy to identify. In addition, when it is difficult to identify the boundary of the angle of view of the first imaging unit 41, it is more preferable that the display processing unit 50c simultaneously performs the frame display described in (1) above.
According to the above (e), the subject can be detected even when the size of the range corresponding to the angle of view of the first imaging unit 41 is fixed in the in-finder monitor 28 regardless of the zoom state of the first imaging unit 41. Can be displayed without interruption. As an example, let us consider a case where the first imaging unit 41 is zoomed up while the size of the range corresponding to the angle of view of the first imaging unit 41 is fixed in the in-finder monitor 28 with reference to FIG. Prior to zooming of the first imaging unit 41, subjects from point A to point C are continuously displayed in the field-of-view confirmation image of the monitor 28 in the finder. Here, when the visual field confirmation image on the in-viewfinder monitor 28 is partially digitally zoomed in conjunction with the zoom-up of the first imaging unit 41, the visual field confirmation image on the in-finder monitor 28 changes as follows. First, the field-of-view confirmation image is zoomed within the range of the angle of view of the first imaging unit 41 and is displayed only up to the range of the point A ′. On the other hand, when the field-of-view confirmation image is displayed as it is outside the range of the angle of view of the first imaging unit 41, the range from point B to point C is displayed. In this case, the subject in the section from point A to point B is displayed. Will be displayed intermittently. However, as shown by the alternate long and short dash line in FIG. 11, if the image is distorted outside the angle of view of the first imaging unit 41, the image can be displayed by connecting the point A ′ to the point C. The subject can be continuously displayed without interrupting the image at the corner boundary.

(F) The display processing unit 50 displays a field-of-view confirmation image by putting a translucent mask outside the angle of view of the first imaging unit 41. In the case of (f), in the field-of-view confirmation image of the in-viewfinder monitor 28, the visibility outside the angle of view of the first imaging unit 41 is reduced, so that it is easy to identify.
Further, the CPU 50 in S114 can execute zooming of the lens 29 and electronic zoom of the visual field confirmation image by the display processing unit 50c in accordance with the user's operation of the zoom switch 48e. At this time, it is preferable that the display processing unit 50c displays information regarding the optical zoom and electronic zoom of the visual field confirmation image on the in-finder monitor 28. Note that FIG.
In the visual field confirmation image shown in FIG. 8, a zoom bar indicating the current zoom state of the second imaging unit 42 and the range in which the magnification can be adjusted is superimposed and displayed with an on-screen function.

Step 115: The CPU 50 determines whether or not the lens position of the zoom lens 15 of the lens unit 12 has changed (whether the lens unit 12 has been zoomed). If the lens position has changed due to the zooming of the lens unit 12 (YES side), the process proceeds to S116. On the other hand, when there is no change in the lens position (NO side), the process proceeds to S117.
Step 116: The CPU 50 re-acquires lens information regarding the lens position of the zoom lens 15 from the lens unit 12. Then, the CPU 50 returns to S113 and repeats the above operation. Thereby, in the display process of S114, the display process part 50c can perform the frame display which reflected the change of the angle of view by zooming of the zoom lens 15. FIG.

Step 117: The CPU 50 determines whether or not there is a photographing instruction by pressing the release button 48a. If there is a shooting instruction (YES side), the process proceeds to S118. On the other hand, if there is no shooting instruction (NO side), the process proceeds to S119.
Step 118: The CPU 50 executes a main image photographing process, and photographs the main image by the first image sensor 23 of the first imaging unit 41. Thereafter, the first imaging unit 41 generates image data of the main image, and the CPU 50 records the image data of the main image on the recording medium 52.

  Here, in the photographing process of the main image in S118, the CPU 50 once cancels the light shielding state by the wide preview display and the light shielding operation, and operates the focus detection unit 25 and the photometry unit 26 to reset the photographing conditions before photographing. . Then, the CPU 50 shoots the main image based on the shooting conditions reset immediately before shooting. In this case, the CPU 50 resumes the wide preview display after the photographing is completed.

Note that the CPU 50 may shoot the main image without canceling the state of the light shielding operation based on the shooting condition of S105. In this case, since the operation for resetting the photographing conditions can be omitted, the subject can be photographed more quickly.
Step 119: The CPU 50 determines whether or not the pressing of the wide preview button 48c is released. When the pressing of the wide preview button 48c is released (YES side), the process proceeds to S120. On the other hand, when the wide preview button 48c is pressed (NO side), the CPU 50 returns to S113 and continues the wide preview display. That is, in the state where the wide preview button 48c is pressed, the CPU 50 continues to display the visual field confirmation image on the in-finder monitor 28 as a moving image.

Step 120: The CPU 50 stops capturing the field-of-view confirmation image by the second imaging unit 42 and turns off the finder monitor 28.
Step 121: The CPU 50 cancels the light shielding state by the light shielding operation. As a result, the user can again observe the subject image by the light flux that has passed through the lens unit 12 from the eyepiece lens 35.

Step 122: The CPU 50 restarts the operations of the focus detection unit 25 and the photometry unit 26. In addition, the CPU 50 instructs the SI unit 27 to resume SI display.
Step 123: The CPU 50 determines whether or not an operation for turning off the power of the camera body 11 has been performed. When the above operation is performed (YES side), the process proceeds to S124. On the other hand, when there is no operation (NO side), the CPU 50 returns to S102 and repeats the above operation.

Step 124: The CPU 50 stops the power supply to the second image sensor 30. This is the end of the description of the operation according to the flowchart of FIG.
The effects of the first embodiment will be described below. In the electronic camera according to the first embodiment, the second photographing unit 42 shoots a visual field confirmation image from an optical path different from that of the first photographing unit 41, and displays the visual field confirmation image on the viewfinder monitor 28 so that the visual field confirmation image can be observed from the eyepiece 35. . Therefore, the user can selectively observe the optical image by the finder optical system and the visual field confirmation image by the second imaging unit 42 according to the situation without taking his eyes off the eyepiece lens 35.

  In particular, when a telephoto lens with a narrow angle of view is attached to the camera body 11, the field of view of the optical image by the finder optical system is narrowed. I can grasp. Therefore, for example, even in a situation where a moving subject is taken by telephoto shooting, for example, the user can track the subject relatively easily, and the possibility of missing a photo opportunity is reduced.

Further, in the electronic camera of the first embodiment, the display processing unit 50c executes an angle-of-view display process that shows the range of the angle of view of the first imaging unit 41 on the view confirmation image (S114). Therefore, in the wide preview display, the user can observe the state of the object scene with the field-of-view confirmation image while paying attention to the range that can be captured by the first imaging unit 41.
(Description of Second Embodiment)
FIG. 12 is a view for explaining the photographing mechanism of the electronic camera in the second embodiment. Here, in the description of the following embodiment, the same reference numerals are given to the components of the camera that are common to the first embodiment, and the duplicate description will be omitted.

The second embodiment is a modification of the first embodiment, and shows an example in which the second imaging unit 42 is attached to the movable member 54 that houses the light emitting unit 53 for flash photography. The base end side of the movable member 54 is pivotally supported on the camera body 11 by a rotation shaft (not shown). The movable member 54 can rotate with respect to the camera body 11 to switch between the first position and the second position.
When the movable member 54 is in the first position, the movable member 54 is accommodated in the camera body 11, and the movable member 54 constitutes a part of the surface of the camera body 11. On the other hand, when the movable member 54 is in the second position, the distal end side of the movable member 54 to which the second imaging unit 42 and the light emitting unit 53 are attached protrudes from the camera body 11 (see FIG. 13). Therefore, when the movable member 54 is at the second position, it is possible to irradiate the subject by the light emission of the light emitting unit 53 and to capture the visual field confirmation image by the second imaging unit 42. Here, the lens 29 and the light emitting unit 53 of the second imaging unit 42 are arranged side by side on the distal end side of the movable member 54.

  In the second embodiment, in addition to the substantially same effect as the first embodiment, the shooting position of the second imaging unit 42 can be greatly separated from the optical axis of the lens unit 12. Therefore, it is possible to reduce the risk of vignetting of the visual field confirmation image with the lens barrel of the lens unit 12 as compared with the case of the first embodiment. In the second embodiment, since the second imaging unit 42 can be stored in the camera body 11 when the movable member 54 is not in use, the design and functionality of the camera body 11 can be improved.

(Description of the third embodiment)
FIG. 14 is a view for explaining the photographing mechanism of the electronic camera system in the third embodiment. FIG. 15 is a block diagram of an electronic camera system in the third embodiment. The third embodiment shows an example in which a camera system 55 is configured by externally attaching a camera unit 55 that captures a visual field confirmation image to the camera body 11.

  The camera system of the third embodiment has a camera body 11 and a camera unit 55. The camera body 11 according to the third embodiment has substantially the same configuration as the camera body 11 according to the first embodiment, except that the camera body 11 does not include the lens attachment part 29a and the second imaging part 42. The camera body 11 communicates with the camera unit 55 via the external I / F 47. In the third embodiment, the camera unit 55 is attached to the hot shoe 31 of the camera body 11.

  On the other hand, as shown in FIG. 14, the camera unit 55 includes an attachment portion 56 that engages with the hot shoe 31, a lens 57 and a lens attachment portion 57 a, and a position adjustment portion 58. The lens 57 and the lens mounting portion 57a are attached to the main body portion 55a of the camera unit 55. The lens 57 can be attached to and detached from the lens attachment portion 57a, and various interchangeable lenses can be attached to the lens attachment portion 57a. The configurations of the lens 57 and the lens mounting portion 57a are substantially the same as the configurations of the lens 29 and the lens mounting portion 29a of the first embodiment.

  The position adjustment unit 58 is a pedestal-like member having a mounting portion 56 on the bottom surface, and supports the main body portion 55a of the camera unit 55 so as to be slidable in the height direction of the camera system (vertical direction in the figure). ing. The position adjustment unit 58 serves to adjust the distance from the optical axis of the lens 57 of the camera unit 55 to the attachment unit 56. Therefore, even if the camera unit 55 is attached to a camera body 11 of a different model, the parallax of the camera unit 55 is adjusted by adjusting the distance between the optical axis of the photographing optical system and the optical axis of the lens 57 by the position adjustment unit 58. Therefore, the compatibility of the camera unit 55 can be improved. Further, the user can prevent the vignetting of the visual field confirmation image by the lens barrel of the lens unit 12 by adjusting the optical axis position of the lens 57 by the position adjusting unit 58.

  As shown in FIG. 15, the camera unit 55 includes an imaging unit 59, a CPU 60, and a communication unit 61. The imaging unit 59 includes an imaging element 59a, an analog processing unit 59b, and a digital processing unit 59c. The image sensor 59a photoelectrically converts the subject image formed through the lens 57 at predetermined intervals and outputs a through image (field-of-view confirmation image). The output signal of the image sensor 59a is input to the analog processing unit 59b. The analog processing unit 59b is an analog front end circuit having a CDS circuit, a gain circuit, an A / D conversion circuit, and the like. The digital processing unit 59c executes color interpolation processing of the through image.

The CPU 60 controls each part of the camera unit 55 based on an instruction from the camera body 11.
The communication unit 61 is connected to the external I / F 47 via the cable 62. The communication unit 61 receives an instruction from the camera body 11 and transmits visual field confirmation image data to the camera body 11.

The operation of the wide preview display by the camera system of the third embodiment is almost the same as that of the first embodiment, except that the camera unit 55 executes the operation of the second image pickup unit 42, and is therefore detailed. Description is omitted.
Also by the camera system of the third embodiment, substantially the same effect as that of the first embodiment can be obtained.

(Supplementary items of the embodiment)
In the above embodiment, an example relating to a single-lens reflex type electronic camera has been mainly described. However, the present invention can also be applied to a silver salt camera that takes a subject image with a film and captures the main image. In the above-described embodiment, the lenses 29 and 57 that capture the field-of-view confirmation image may be configured such that the camera body 11 or the camera unit 55 cannot be replaced.

  The present invention can be implemented in various other forms without departing from the spirit or the main features thereof. For this reason, the above-described embodiment is merely an example in all respects and should not be interpreted in a limited manner. The present invention is defined by the claims, and the present invention is not limited to the text of the specification. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

Explanatory drawing of the imaging mechanism of the electronic camera in 1st Embodiment Front view of the camera body in the first embodiment Block diagram of the camera body in the first embodiment Flowchart showing the operation of the electronic camera related to the wide preview display in the first embodiment The figure which shows the display state of the optical image of a to-be-photographed object in a finder optical system The figure which shows the state of the camera body at the time of wide preview display The figure which shows an example of a wide preview display when lens information cannot be acquired The figure which shows the example which displayed the angle of view of the 1st imaging part on the frame by the wide preview display Explanatory drawing when changing the display mode of the visual field confirmation image in the wide preview display (A) Explanatory diagram when displaying the field-of-view confirmation image with barrel distortion, (b) Explanatory diagram when displaying the field-of-view confirmation image distorted in the horizontal direction Explanatory drawing showing the display range when the field-of-view confirmation image is distorted Explanatory drawing of the imaging mechanism of the electronic camera in 2nd Embodiment The perspective view which shows the state which has a movable member in a 2nd position. Explanatory drawing of the imaging mechanism of the electronic camera system in 3rd Embodiment The block diagram of the electronic camera system in 3rd Embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Camera body, 12 ... Lens unit, 13 ... Mount, 23 ... 1st image sensor, 28 ... Monitor in a finder, 29 ... Lens, 30 ... 2nd image sensor, 32 ... Diffusing screen (focus plate), 33 ... Condenser Lens 34... Pentaprism 35. Eyepiece 41. First imaging unit 42. Second imaging unit 47. External I / F 50. CPU 50 c Display processing unit 55 Camera unit 56. Attaching part, 57 ... lens, 59 ... imaging part, 61 ... communication part

Claims (12)

A first imaging unit that captures an image for recording;
A finder optical system having an eyepiece capable of observing an optical image of a subject by a light beam from a photographing optical path of the first imaging unit;
A second imaging unit that captures a visual field confirmation image from an optical path different from that of the first imaging unit;
A display processing unit that executes an angle-of-view display process that indicates a range of an angle of view of the first imaging unit in the visual field confirmation image;
A display unit for presenting the visual field confirmation image subjected to the angle-of-view display processing to the eyepiece unit;
A control unit that switches between a first state in which the optical image is presented to the eyepiece unit and a second state in which the visual field confirmation image is presented to the eyepiece unit;
A camera comprising: A camera to which an external camera unit can be attached,
An attachment for connecting the camera unit;
An imaging unit for capturing images for recording;
A finder optical system having an eyepiece capable of observing an optical image of a subject by a light flux from a photographing optical path of the imaging unit;
A communication unit that receives, from the camera unit, a field-of-view confirmation image captured in a different optical path from the imaging unit;
A display processing unit that executes an angle-of-view display process that indicates a range of an angle of view of the imaging unit in the visual field confirmation image;
A display unit for presenting the visual field confirmation image subjected to the angle-of-view display processing to the eyepiece unit;
A control unit that switches between a first state in which the optical image is presented to the eyepiece unit and a second state in which the visual field confirmation image is presented to the eyepiece unit;
A camera comprising: The camera according to claim 1 or 2,
The display processing unit superimposes a frame indicating the range of the angle of view on the visual field confirmation image. The camera according to claim 3.
The display processing unit changes a display color of the frame based on at least one of luminance and hue of the visual field confirmation image. The camera according to claim 1 or 2,
The display processing unit makes the display of the visual field confirmation image different between the inside and the outside of the angle of view. The camera according to claim 5, wherein
The display processing unit performs image processing using a smoothing filter or a contour extraction filter on a portion corresponding to the outside of the angle of view in the data of the visual field confirmation image. The camera according to claim 5, wherein
The display processing unit color-displays the inside of the angle of view in the visual field confirmation image and displays the outside of the angle of view in black and white. The camera according to claim 5, wherein
The display processing unit performs image processing for distorting a portion corresponding to the outside of the angle of view of the visual field confirmation image. The camera according to claim 5, wherein
The camera according to claim 1, wherein the display processing unit lowers the luminance outside the angle of view in the visual field confirmation image as compared with the inside of the angle of view. The camera according to claim 5, wherein
The display processing unit performs image processing for lowering the resolution of the portion corresponding to the outside of the angle of view in the data of the visual field confirmation image, as compared with the image inside the angle of view. . The camera according to claim 1 or 2,
An interchangeable lens is detachable, and further includes a mount unit that acquires angle-of-view information about the angle of view from the interchangeable lens,
The display processing unit stops the angle-of-view display processing in the second state when the angle-of-view information cannot be acquired. The camera according to claim 1 or 2,
An interchangeable lens is detachable, and further includes a mount unit that acquires angle-of-view information about the angle of view from the interchangeable lens,
The display processing unit displays an error display on the display unit in the second state when the angle-of-view information cannot be acquired.

Images