JP6149346B2 - Imaging device - Google Patents

Description

  The present invention relates to a photographing apparatus.

  A technique is known in which an imaging sensor is moved in the direction of the optical axis of a lens and focused to perform imaging (for example, Patent Document 1).

JP 2005-17699 A

When the conventional technology is realized, the movable range of the photographing sensor may be limited due to the influence of the type and characteristics of the lens, but the conventional technology does not consider the limitation. In addition, it is complicated for the user himself to consider the restriction every time shooting is performed.
The present invention has been made in view of the above problems, and an object thereof is to provide a technique capable of determining the position of a photographing sensor in accordance with the type and characteristics of a lens.

  An imaging apparatus according to the present invention is an imaging apparatus that performs imaging using an imaging sensor that detects light that has passed through a lens, and adjusts the size of the flange back by moving the imaging sensor in the optical axis direction of the lens by a moving unit. It is possible. Then, the lens information (focal length or the like) is acquired, and the photographing sensor is moved so that the flange back according to the lens information (focal length or the like) is obtained. That is, in the photographing apparatus, when the position of the lens, the position of the photographing sensor, and the position of the subject are in a specific relationship, the focus of the subject is adjusted by adjusting the lens position to form an image on the photographing sensor. Can be taken.

  When the lens is moved, the movable range of the lens is restricted in order to maintain a state in which the lens is not in contact with a structure such as a photographing sensor. Therefore, if the photographing sensor is moved so that the flange back according to the lens information (focal length, etc.) is obtained, the lens is moved within the movable range, and an image is formed on the photographing sensor by the lens. It is possible to adjust the position of the imaging sensor so as to maintain the positional relationship as possible.

  For example, in a retro-focus type lens, the main point of the lens generally exists in the back focus when the lens is closest to the shooting sensor (between the end point closest to the shooting sensor in the lens and the shooting sensor). Therefore, the focal length is less than the back focus when the lens is closest to the photographing sensor. When the focal length and the flange back match, the distance between the lens principal point and the shooting sensor (= focal length) matches the flange back. In the case of shooting at one point above, shooting is performed without moving the lens position from the state where the focal length and the flange back coincide. On the other hand, in order to shoot a subject closer to infinity, it is necessary to move the lens main point away from the image sensor, and in order to move the lens main point away from the image sensor in a retrofocus type lens, the lens is photographed. Need to keep away from the sensor. Therefore, even if the focus adjustment is performed after moving the shooting sensor so that the focal length of the lens matches the flange back, the distance between the lens and the shooting sensor can always be kept larger than the focal length. It is possible to prevent the lens and the image sensor from coming into contact with each other. In order to prevent the lens and the image sensor from coming into contact, the focal length of the lens and the back focus when the lens is closest to the image sensor (the back focus when focused at infinity) are matched. You may comprise.

  Further, the retrofocus type lens is configured by a combination of a concave lens and a convex lens, and at least one concave lens is present on the subject side as compared with at least one convex lens. The principal point moves away from the imaging sensor as the refraction of the concave lens is decreased (the curvature is decreased). Therefore, when comparing two types of retrofocus lenses in which the concave lens is different in refraction and the other lenses have the same configuration, the lens having the smaller concave lens has a principal point on the subject side. Then, according to the configuration of the present application in which the position of the image sensor can be adjusted according to the focal length in both of these two types of retrofocus type lenses, the image sensor is moved to a position where the subject can be imaged in both. It is possible to take a picture using a smaller lens (a lens having a smaller refraction). Therefore, it is possible to reduce the size of the lens at each focal length in the lens system used in the photographing apparatus.

  In the photographing apparatus, the control unit controls the moving unit to move the photographing sensor so that the flange back according to the lens information (focal length, etc.) is obtained, and then the moving unit is moved without changing the flange back. It is preferable to perform focus adjustment by controlling. In other words, after adjusting the size of the flange back by moving the shooting sensor first, the focus is adjusted so that the distance between the lens and the shooting sensor is always kept at or above the focal length even if the focus adjustment is performed. It is possible to adjust the focus while preventing the lens and the image sensor from coming into contact with each other.

  Furthermore, the method of adjusting the flange back according to the focal length of the lens as in the present invention can be applied as a program or method. In addition, the apparatus, program, and method as described above may be realized as a single apparatus, or may be realized using a shared component in an apparatus having multiple functions. Is included.

It is a block diagram of the imaging device concerning the embodiment of the present invention. (2A), (2B), and (2C) are diagrams showing the positional relationship between the lens and the imaging sensor. It is a flowchart which shows an imaging | photography process.

Here, embodiments of the present invention will be described in the following order.
(1) Configuration of photographing apparatus:
(2) Shooting process:
(3) Other embodiments:

(1) Configuration of photographing apparatus:
FIG. 1 shows a photographing apparatus 1 according to an embodiment of the present invention. The photographing apparatus 1 includes an optical system 10, a photographing sensor 14, a moving unit 14a, a storage unit 15, a display unit 20, a recording unit 30, An input unit 40, a focus adjustment unit 43, an aperture adjustment unit 45, a shutter control unit 50, an exposure control unit 60, a CPU 70, and an image generation unit 80 are provided. In accordance with a predetermined program, the CPU 70 moves the moving unit 14a, the focus adjustment unit 43, the aperture adjustment unit 45, the shutter control unit 50, the exposure control unit 60, the storage unit 15, the image generation unit 80, the display unit 20, the recording unit 30, and the input. The operation of the unit 40 is controlled.

  The optical system 10 includes a lens 11 that forms an image of a subject on the image sensor 14, an aperture 12, and a shutter 13. In the present embodiment, the lens 11 and the diaphragm 12 are provided in a lens barrel, and the lens barrel is attached to a housing (not shown) in a replaceable manner. In the present embodiment, the lens 11 is a so-called retrofocus type lens and includes a plurality of lenses arranged along a direction parallel to the optical axis. In FIG. expressing. Each lens is supported by the outer edge portion, and focus adjustment can be performed by making one or all of the lenses movable in the optical axis direction. The position of the lens 11 is configured to be controlled by the focus adjustment unit 43. When the focus adjustment unit 43 is instructed to adjust the lens position, the focus adjustment unit 43 moves the lens 11 to adjust the focus. I do. In this embodiment, a memory and a communication circuit (not shown) are provided in the lens barrel, and information (lens information) indicating the focal length of the lens 11 is recorded in the memory. The CPU 70 can communicate via a communication circuit in the lens barrel with the lens barrel attached to the housing, and can acquire lens information recorded in the memory.

  In the present embodiment, the diaphragm 12 is constituted by a plurality of shielding plates that are rotatably supported in a plane perpendicular to the optical axis of the lens 11, and the plurality of shielding plates rotate in conjunction with each other. Thus, it is possible to change the area of the unshielded portion in a plane perpendicular to the optical axis. The aperture diameter of the aperture 12 is configured to be controlled by an aperture adjuster 45. When the aperture adjuster 45 is instructed about the aperture diameter of the aperture 12, the aperture adjuster 45 drives the aperture 12 to Set to the indicated opening diameter.

  The shutter 13 is a mechanical focal-plane shutter, and includes a plurality of open / close (foldable) light-shielding curtains as flat plate-shaped light-shielding portions parallel to the imaging sensor surface of the imaging sensor 14. The light-shielding curtain is configured to move in a direction perpendicular to the optical axis in accordance with a control signal from the shutter control unit 50. Normally, the light-shielding curtain does not block the optical path in the direction parallel to the optical axis. Is retained. In addition, in a state where the light shielding curtain is held without blocking the light path, when a predetermined trigger is given, the state where the light shielding curtain is held without blocking the light path is released, and the light shielding curtain is moved with respect to the optical axis. Thus, the blades are driven in the vertical direction, and the plurality of blades block the optical path. In FIG. 1, the moving direction of the light-shielding curtain is indicated by a dashed arrow Am.

  The imaging sensor 14 is a CMOS (Complementary Metal Oxide Semiconductor) image sensor that includes a color filter arranged in a Bayer array and a plurality of light receiving elements (photodiodes) that accumulate charges corresponding to the amount of light for each pixel by photoelectric conversion. Of course, the image sensor may be another sensor such as a CCD (Charge Coupled Device) image sensor. The imaging sensor 14 according to the present embodiment performs a reset operation for resetting the accumulated charge corresponding to the amount of light received by the light receiving element when the exposure control unit 60 issues a reset instruction, and may start exposure at each light receiving element. it can. Further, the image sensor 14 can end the exposure by reading out information indicating the amount of light received by the light receiving element when the exposure control unit 60 issues a reading instruction.

  When a recording image is captured by the imaging apparatus 1 according to the present embodiment (normal imaging), the exposure time is controlled by a combination of the shutter 13 that is a mechanical shutter and the electronic shutter of the imaging sensor 14. That is, in the case of normal shooting in this embodiment, the exposure time is controlled by an electronic front curtain-mechanical rear curtain shutter system in which exposure is started by the electronic shutter in the photographing sensor 14 and exposure is ended by the light shielding curtain of the shutter 13. Is done. Specifically, in the case of normal shooting, exposure is started in a line-sequential manner with an electronic shutter, and the light is shielded by a mechanical shutter so that each line is shielded at the timing at which the exposure time for each line reaches a set shutter speed. Is started. In the photographing apparatus 1, live view display can be performed on the display unit 20, and when an image for performing the live view display is photographed, the exposure time is controlled by an electronic shutter method. That is, both the front curtain and the rear curtain are controlled by the electronic shutter.

  The moving unit 14 a moves the photographing sensor 14 in the direction of the optical axis As of the lens 11 in accordance with a control signal from the CPU 70. The moving unit 14a only needs to be able to move the image sensor 14 in the direction of the optical axis As, and various mechanisms can be adopted for the movement. For example, it is possible to employ a configuration in which a member that supports the image sensor 14 is supported by a rail that extends in the direction of the optical axis As, and a member that supports the image sensor 14 is moved along the rail by a driving source such as various motors. is there. Of course, other configurations such as a ball screw and a rack and pinion mechanism may be employed, or a mechanism similar to the mechanism for moving the lens 11 may be used.

  In the present embodiment, when the CPU 70 acquires information such as the focal length of the lens 11, the CPU 70 sends a control signal for moving the imaging sensor 14 to the moving unit 14 a so that the focal length matches the flange back. Output. That is, in the moving unit 14a, when the size of the flange back is instructed by the control signal, the moving amount of the imaging sensor 14 necessary to obtain the instructed flange back size is specified, and only the moving amount is determined. The imaging sensor 14 is moved.

FIG. 2A is a diagram schematically illustrating the lens 11. The lens 11 shown in this example includes a concave lens 11a and a convex lens 11b. In FIG. 2A, the position of the optical axis As the direction of the imaging sensor 14 side of the end point E of the convex lens 11b is located P _1, the position of the optical axis As the direction of the mounting surface of the lens 11 is located P _2, imaging sensor The position in the optical axis As direction of the 14 imaging surface is the position P ₃ . In FIG. 2A, the parallel light traveling from the left side toward the image sensor 14 intersects at the position P ₃ of the image sensor 14. Therefore, in FIG. 2A, the back focus when focused to infinity by the lens 11 is L ₁ , and the flange back is L ₂ .

Since the CPU 70 moves the photographing sensor 14 so that the focal length and the flange back coincide with each other, the position of the principal point P becomes the position P ₂ and the focal length is L ₂ after the movement. In the retrofocus type lens, the principal point P of the lens 11 exists between the end point E of the convex lens 11b on the image sensor 14 side and the image sensor 14. Accordingly, the focal length L ₂ is always less than or equal to the back focus L ₁ .

In FIG. 2A, light traveling from the left side of the drawing in parallel with the optical axis As (light from infinity) converges to one point on the image sensor 14, so that light from infinity can be photographed at one point. On the other hand, in order to photograph a subject closer to infinity, the principal point of the lens 11 is moved away from the photographing sensor 14. That is, as shown in FIG. 2B, by distancing the concave lens 11a and a convex lens 11b from the imaging sensor 14, performs focus adjustment by moving the subject side than the position P ₂ of the mounting surface of the position of the principal point P is the lens 11 It will be. Therefore, even if the focus adjustment is performed after the photographing sensor is moved so that the focal length of the lens 11 and the flange back coincide with each other, the lens 11 (the convex lens 11b in the example shown in FIGS. 2A and 2B) and the photographing sensor 14 Can always be kept larger than the focal length L ₂ , and contact between the lens 11 and the image sensor 14 can be prevented.

Further, in the retrofocus type lens as shown in FIGS. 2A and 2B, at least one concave lens 11a is present on the subject side as compared with at least one convex lens 11b. The principal point P moves away from the image sensor as the refraction of the concave lens 11a is decreased (the curvature is decreased). For example, FIG. 2C is a diagram in the case where only the concave lens 11a is changed to a thinner concave lens 11c from the lens configuration shown in FIG. 2A, and the position of the principal point P when the concave lens 11c is used as shown in FIG. The position P ₄ is closer to the subject than the position P ₂ . Then, as in the present, if an adjustable arrangement the position of the optical axis As the direction of the imaging sensor 14, the flange back and the focal length even in the lens system as shown in FIG. 2C and (L ₄ shown in FIG. 2C) It is possible to perform photographing by moving the photographing sensor 14 so as to match. Accordingly, it is possible to perform photographing using a smaller lens (a lens having a smaller refraction), and it is possible to reduce the size of the lens at each focal length in the lens system used in the photographing apparatus 1. is there.

  The display unit 20 includes an interface circuit (not shown), a liquid crystal panel driver, a liquid crystal panel, an eyepiece (not shown), and the like. In the present embodiment, the display unit 20 is an EVF (Electronic View Finder) that displays an image showing a subject to be photographed and allows the user to grasp information such as the state of the subject before photographing and photographing conditions. The photographing apparatus 1 according to the embodiment is a mirrorless digital camera provided with an EVF.

  The recording unit 30 can insert a recording medium (not shown), and records information on the recording medium and reads information from the recording medium with the recording medium inserted in the recording unit 30. Can do. That is, the image data indicating the photographed image can be recorded on the recording medium. The storage unit 15 is a memory that temporarily records image data (information indicating the amount of received light for each light receiving element) output from the imaging sensor 14.

  The image generation unit 80 is configured by a circuit that generates image data by executing various processes according to a predetermined procedure for the received light amount information for each pixel and each color output from the imaging sensor 14. The image processing executed by the image generation unit 80 includes processing for outputting an evaluation value for performing AE (Automatic Exposure) processing and an evaluation value for performing AF (Automatic Focus) processing. That is, the image generation unit 80 specifies an evaluation value (for example, an average value of luminance) for evaluating the brightness of pixels included in a predetermined photometry area set within a shooting range by the shooting sensor 14, It is possible to output as an evaluation value for performing AE processing. The CPU 70 outputs a control signal to the aperture adjustment unit 45, the shutter control unit 50, and the exposure control unit 60 based on the evaluation value for performing the AE process, and adjusts the exposure so that the proper exposure is obtained. That is, the CPU 70 has a function of specifying shooting conditions when shooting image data based on an instruction or default setting in the input unit 40 and setting each unit according to the shooting conditions. More specifically, the CPU 70 specifies shooting conditions necessary for achieving proper exposure based on the evaluation value for performing the above-described AE processing, and the aperture 12, shutter speed, and shutter 13 position are set according to the shooting conditions. A control signal is output to the aperture adjustment unit 45, the shutter control unit 50, and the exposure control unit 60 so as to be set. Note that the shooting conditions necessary for achieving proper exposure can be specified under various preconditions (for example, aperture priority, shutter speed priority, etc.).

  In addition, the image generation unit 80 evaluates the degree of focus of pixels included in a predetermined distance measurement area set within the shooting range by the shooting sensor 14 (for example, a value indicating the magnitude of contrast, etc.). ) Can be specified and output as an evaluation value for performing the AF process. The CPU 70 outputs a control signal to the focus adjustment unit 43 based on the evaluation value for performing the AF process, and adjusts the exposure so as to be in focus. That is, the CPU 70 outputs a control signal to the focus adjustment unit 43 to change the position of the lens 11 until the evaluation value for performing the above-described AF processing is within a predetermined range indicating that it is in focus, Realize in-focus state.

  The input unit 40 includes a shutter button, an input unit for switching a shooting mode, an input unit for switching an aperture, an input unit for switching a shutter speed, and an input unit for operating various setting menus. The user can give various instructions to the photographing apparatus 1 by operating the input unit 40. In this embodiment, the stroke amount of the shutter button can be detected in two stages. That is, it is possible to distinguish and detect a state where the shutter button is half-pressed and a state where the shutter button is fully pressed. Also, in this embodiment, when the shutter button is half-pressed, it is considered that an instruction to determine exposure and focus adjustment is performed while continuing the live view display, and when the shutter button is fully pressed, recording is performed. It is considered that an instruction to record an image on the medium is given.

  With the above configuration, in the present embodiment, it is possible to perform shooting while the imaging sensor 14 is moved so that the lens 11 and the imaging sensor 14 can be prevented from coming into contact with each other. In addition, it is possible to reduce the size of the lens at each focal length in the lens system used in the photographing apparatus 1.

(2) Shooting process:
Next, a photographing process in the present embodiment will be described in detail with an example. FIG. 3 is a flowchart of a photographing process that starts in response to entering the photographing mode or changing the lens during the photographing mode. In the initial state, the image sensor 14 is located at a position farthest from the lens 11. The CPU 70 normally executes processing for performing live view display on the display unit 20 and executes processing for capturing an image for recording when the shutter button is fully pressed. In the present embodiment, the photographing sensor 14 is moved based on the lens information before performing live view display. For this reason, the CPU 70 acquires information (focal length and the like) of the lens 11 (step S100). That is, the CPU 70 acquires the focal length of the lens 11 by acquiring the information of the lens 11 recorded in the memory in the lens 11 via the communication circuit in the lens barrel that contains the lens 11. The CPU 70 may acquire the lens name from the lens 11 or the user's input operation, and may acquire the focal length of the lens 11 from the lens name using a table that the CPU 70 has in advance.

  Next, the CPU 70 moves the photographing sensor so that the focal length = flange back (step S105). That is, the CPU 70 outputs a control signal indicating the focal length acquired in step S100 to the moving unit 14a. When the moving unit 14a acquires the control signal, the moving distance of the photographing sensor 14 necessary for matching the focal length indicating the control signal with the flange back is specified, and the photographing sensor 14 is moved by the moving distance. . As a result, for example, as shown in FIG. 2A, a state in which the focal length matches the flange back is realized.

  Next, the CPU 70 adjusts the aperture 12 so as to have an aperture diameter corresponding to the set value of the aperture 12 set by the user (step S110). That is, the user sets the F value of the diaphragm 12 in advance by the input unit 40. The CPU 70 outputs a control signal for adjusting the diaphragm 12 to the set F value to the diaphragm adjusting unit 45, and the diaphragm adjusting unit 45 controls the diaphragm 12 so that the aperture diameter corresponds to the F value of the diaphragm 12. To do.

  When the aperture diameter of the diaphragm 12 is controlled to be a set value set by the user, the AE process is executed next. That is, in the state where the aperture diameter of the diaphragm 12 becomes a set value set by the user, the image generating unit 80 evaluates to evaluate the brightness of the pixels in the photometric area set in advance within the photographing range of the light receiving sensor. A value is specified and output as an evaluation value for performing AE processing on the CPU 70 (step S115). Note that the shutter speed at this stage is a default value (or a set value at the time of the previous shooting).

  Next, the CPU 70 adjusts the shutter speed so as to achieve proper exposure based on the evaluation value for performing the AE process (step S120). That is, the CPU 70 compares the evaluation value for performing the AE process with a predetermined appropriate exposure range, and specifies the shutter speed necessary for the evaluation value for performing the AE process to fall within the proper exposure range. . Then, the CPU 70 outputs a control signal indicating the shutter speed to the exposure control unit 60. As a result, the exposure control unit 60 adjusts the shutter speed of the electronic shutter in the light receiving sensor so that the evaluation value for performing the AE process becomes a shutter speed necessary for entering the appropriate exposure range.

  With the AE process as described above, the CPU 70 delivers the image data generated by the image generation unit 80 to the display unit 20 in a state where the exposure of the image to be shot is appropriate exposure, and the display unit 20 performs the image after the AE process. Is in a live view display state. Next, the CPU 70 determines whether or not the shutter button has been half-pressed (step S125). If it is not determined that the shutter button has been half-pressed, the processing from step S110 is repeated. On the other hand, if it is determined in step S125 that the shutter button is half-pressed, the CPU 70 specifies an evaluation value for evaluating the contrast of the distance measurement area set in advance within the photographing range of the light receiving sensor, and the CPU 70. Is output as an evaluation value for performing AF processing on (step S130). Then, the CPU 70 outputs a control signal to the focus adjustment unit 43 based on the evaluation value, and performs the focus adjustment by moving the lens 11 so that the evaluation value is included in the predetermined focusing range (step S135). . In addition, since the imaging sensor 14 is disposed at a position where the focal length of the lens 11 and the flange back coincide before the focus adjustment, the lens 11 does not approach the imaging sensor 14 in the focus adjustment.

  Next, the CPU 70 determines whether or not the state in which the shutter button is pressed is released (step S140). If it is determined that the shutter button is released, the processing after step S110 is performed. repeat. On the other hand, if it is determined in step S140 that the shutter button has been fully pressed, the CPU 70 captures an image for recording and records it on a recording medium (step S145). That is, the CPU 70 outputs a control signal to the exposure control unit 60 to start exposure in the photographing sensor 14 and outputs a control signal to the shutter control unit 50 to start the movement of the shutter 13. Here, the movement start timing of the shutter 13 is adjusted so that the exposure ends with the exposure time corresponding to the shutter speed set in step S120. When the movement of the light shielding curtain of the shutter 13 is completed, the CPU 70 outputs a control signal to the exposure control unit 60 and performs reading from all the pixels on the photographing sensor 14. As a result, since the image data is output from the image sensor 14 to the storage unit 15, the CPU 70 outputs a control signal to the image generation unit 80, and performs predetermined processing on the image data output to the storage unit 15. The image processing is executed, and the image data indicating the result is recorded on the recording medium inserted in the recording unit 30. Thereafter, the processing after step S110 is repeated. According to the above processing, after adjusting the position of the image sensor 14 so that the flange back coincides with the focal length, it is possible to perform imaging while adjusting the focus while maintaining the position of the image sensor 14. Note that when the power is turned off or the lens is exchanged, the photographing sensor 14 is located at a position farthest from the lens 11.

(3) Other embodiments:
The above embodiment is an example for carrying out the present invention. As long as the flange back is adjusted according to the focal length of the lens, the following modifications may be combined as appropriate, and various other embodiments may be used. It can be adopted.

  For example, in the above-described embodiment, the display unit 20 is an EVF using a liquid crystal panel, but the display unit 20 is a display unit other than the EVF, for example, a display unit using a liquid crystal panel attached to the back of the photographing apparatus 1. It may be, or a system using a system other than the liquid crystal panel may be used. The photographing apparatus 1 may be a single-lens reflex camera provided with a mirror, a movie camera, or a device such as a mobile phone having a photographing function. Furthermore, in the above-described photographing sensor 14, the color filter is a Bayer array, but the present invention may be applied to a photographing apparatus using a sensor configured with an array other than the Bayer array. For example, the present invention may be applied to a photographing apparatus using a 3CCD or a three-layer sensor.

  Further, the lens 11 may be configured such that an optical zoom operation can be executed by making one or all of the lenses movable in the optical axis direction. In this case, after the focal length is adjusted by the zoom operation, the photographing sensor 14 is moved so that the focal length matches the flange back.

DESCRIPTION OF SYMBOLS 1 ... Imaging device, 10 ... Optical system, 11 ... Lens, 11a ... Concave lens, 11b ... Convex lens, 11c ... Concave lens, 12 ... Aperture, 13 ... Shutter, 14 ... Shooting sensor, 14a ... Moving part, 15 ... Memory | storage part, 20 Display unit, 30 Recording unit, 40 Input unit, 43 Focus adjustment unit, 45 Adjustment unit, 50 Shutter control unit, 60 Exposure control unit, 70 CPU, 80 Image generation unit

Claims (4)

A photo sensor that detects the light passing through the lens;
A moving unit that moves the photographing sensor in the optical axis direction of the lens;
An acquisition unit for acquiring a focal length of the lens;
Wherein by controlling the moving unit, imaging device and a said imaging sensor controller Before moving so as to have a focal length matching flange back of the lens before performing the imaging. The imaging apparatus according to claim 1, wherein the control unit moves the imaging sensor to a position farthest from the lens when the power is turned off. The imaging device according to claim 1 , wherein the control unit moves the imaging sensor to a position farthest from the lens when exchanging the lens. Focus in which the control unit controls the moving unit to move the image sensor so that the flange back according to the lens information is obtained, and then performs focus adjustment by controlling the lens without changing the flange back. An adjustment unit;
Imaging device according to any one of claims 1 to 3.

Images