Imaging device

Abstract

To provide an imaging device capable of performing good communication while suppressing an increase in size.SOLUTION: An imaging device has: a first member made of a conductive member; a second member made of a non-conductive member; and a first antenna and a second antenna arranged between the first member and the second member and capable of wireless communication. The first antenna has a first surface having a first pattern formed thereon and perpendicular to an optical axis direction, the second antenna has a second surface having a second pattern formed thereon and inclined relative to the first surface, and the first antenna and the second antenna are arranged so as not to overlap each other when viewed from the optical axis direction and when viewed from a direction perpendicular to the second surface.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to an imaging device equipped with an antenna for transmitting and receiving radio waves such as wireless communication. [Background technology]

[0002] BACKGROUND ART Conventionally, imaging devices equipped with an antenna for transmitting images to the outside via wireless communication are known (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7009589 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, a wireless communication technology called Multi Input Multi Output (hereinafter referred to as MIMO) has been used, which can increase the amount of data handled in a certain period of time by transmitting and receiving data using multiple antennas. However, Patent Document 1 does not describe the arrangement of multiple antennas suitable for using MIMO. Because MIMO uses multiple antennas for communication, if the antennas are arranged close to each other to prevent the system from becoming too large, radio interference may occur, and sufficient wireless communication performance may not be achieved.

[0005] An object of the present invention is to provide an imaging device that is capable of performing good communication while suppressing an increase in size. [Means for solving the problem]

[0006] An imaging device according to one aspect of the present invention comprises a first member made of a conductive material, a second member made of a non-conductive material, and a first antenna and a second antenna arranged between the first member and the second member and capable of wireless communication, wherein the first antenna has a first surface on which a first pattern is formed and which is perpendicular to the optical axis direction, and the second antenna has a second surface on which a second pattern is formed and which is inclined relative to the first surface, and the first antenna and the second antenna are arranged so as not to overlap each other when viewed from the optical axis direction and when viewed from a direction perpendicular to the second surface. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide an imaging device that is capable of performing good communication while suppressing an increase in size. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is an external view of an imaging device according to a first embodiment. [Figure 2] 1 is a block diagram of an imaging device according to a first embodiment. [Figure 3] 2A and 2B are diagrams illustrating a configuration of a top cover unit of the imaging apparatus according to the first embodiment. [Figure 4] FIG. 2 is a diagram illustrating a storage configuration of a communication unit according to the first embodiment. [Figure 5] FIG. 2 is a diagram illustrating an antenna configuration of a communication unit according to the first embodiment. [Figure 6] FIG. 2 is a diagram illustrating a storage configuration of a communication unit according to the first embodiment. [Figure 7] FIG. 10 is a diagram illustrating a correlation coefficient of a communication unit according to the first embodiment. [Figure 8] FIG. 3(b) is a cross-sectional view taken along line AA in FIG. [Figure 9] 3A and 3B are diagrams illustrating an example of a posture in which the imaging device of the first embodiment is held. [Figure 10] FIG. 10 is a diagram showing an imaging device according to a second embodiment attached to a tripod. [Figure 11]10 is an explanatory diagram illustrating a case where a first communication unit and a second communication unit of a second embodiment are attached to a grip unit. FIG. [Figure 12] FIG. 10 is an exploded perspective view illustrating the configuration of an imaging device according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to designate the same components, and redundant explanations will be omitted. (First embodiment) Fig. 1 is an external view of a digital camera 1 as an example of an imaging device of this embodiment. Fig. 1(a) and Fig. 1(b) are respectively a front perspective view and a rear perspective view of the digital camera 1. Fig. 2 is a block diagram of the digital camera 1.

[0010] The display unit is provided on the rear surface of the digital camera 1, and displays images and various information. The touch panel a can detect touch operations on the display surface (operation surface) of the display unit .

[0011] The terminal cover 40 protects connectors such as a headphone terminal 41 that connects an external device to the digital camera 1. By connecting headphones to the headphone terminal 41, electronic sounds from the digital camera 1 can be heard through the headphones.

[0012] The outside viewfinder display section 43 is provided on the top surface of the digital camera 1 and displays various settings of the digital camera 1 such as the shutter speed and aperture.

[0013] The mode changeover switch 60 is an operation unit for switching between various modes.

[0014] The shutter button 61 is an operation unit for issuing shooting instructions, and is a switch with a two-stage detection unit in the direction of depression. Autofocus operation is performed when the shutter button 61 detects ON at the first stage, and shooting operation is performed when ON at the second stage. Note that the operation performed when ON at the first stage is detected can be changed using a function for customizing the operation button; for example, it is possible to perform only autoexposure operation without performing autofocus operation.

[0015] The main electronic dial 71 is a rotary operation member included in the operation unit 70. By turning the main electronic dial 71, it is possible to change settings such as shutter speed and aperture.

[0016] 2. It should be noted that the operation members such as the push buttons and dials shown in FIG. 1 are included in the operation unit 70 shown in FIG.

[0017] The power switch 72 is used to turn the power of the digital camera 1 on and off.

[0018] The sub electronic dial 73 is a rotary operation member that is used to move the selection frame, advance through images, and the like.

[0019] The video button 76 is used to instruct the start and stop of video shooting (recording).

[0020] The AE lock button 77 can fix the exposure state by pressing it in the shooting standby state.

[0021] The enlargement button 78 is used to turn on / off the enlargement mode in the live view (LV) display in the shooting mode. After turning on the enlargement mode, the LV image can be enlarged or reduced by operating the main electronic dial 71. The enlargement button 78 is used to increase the magnification of the playback image in the playback mode.

[0022] The playback button 79 is used to switch between the shooting mode and the playback mode. Pressing the playback button 79 during the shooting mode switches to the playback mode, and the most recent image recorded on the recording medium 200 can be displayed on the display unit 28.

[0023] The menu button 81 is used to display a menu screen on the display unit 28 that allows various settings. The cross button 74 includes at least up, down, left, and right buttons. The SET button 75 is mainly used to confirm selected items, etc. The user (photographer) can intuitively make various settings using the menu screen displayed on the display unit 28, the SET button 75, and the cross button 74.

[0024] The eyepiece finder (peek-in type finder) includes an eyepiece 16 and an EVF unit 29 provided therein. The user can view an image displayed on the EVF unit 29 through the eyepiece 16.

[0025] The eyepiece detector 57 is an eyepiece detection sensor (approach detector) that detects whether or not the user places his / her eye close to the eyepiece 16, and is disposed inside the eyepiece 16.

[0026] The speaker 120 can play back predetermined electronic sounds and the audio of captured video data based on instructions from the system control unit 50.

[0027] The cover 202 is a cover for a slot in which the recording medium 200 is stored.

[0028] The grip portion (handling portion) 82 has a shape that protrudes toward the subject side beyond the imaging surface so that the user can take pictures comfortably.

[0029] The lens unit 150 includes the lens 103 and is configured to be detachable from the digital camera 1. The lens 103 is usually made up of multiple lenses, but for simplicity, only one lens is shown in FIG.

[0030] The lens side communication terminal 6 is used when the lens unit 150 communicates with the digital camera 1. The camera side communication terminal 10 is used when the digital camera 1 communicates with the lens unit 150.

[0031] The lens unit 150 communicates with the system control unit 50 via the lens side communication terminal 6 and the camera side communication terminal 10. The lens system control circuit 4 controls the aperture 5 via the aperture drive circuit 2, and adjusts the focus by displacing the position of the lens 103 via the AF drive circuit 3.

[0032] The AE sensor 17 measures the brightness of the subject through the lens unit 150 .

[0033] The focus detection unit 11 outputs defocus amount information to the system control unit 50. The system control unit 50 controls the lens unit 150 based on the defocus amount information to perform phase difference AF. The focus detection unit 11 may be a dedicated phase difference sensor, or may be configured as an imaging surface phase difference sensor of the image sensor 22.

[0034] The shutter 101 is a focal plane shutter for controlling the exposure time of the image sensor 22 under the control of the system control unit 50 .

[0035] The image sensor 22 is configured with a CCD, CMOS element, etc., and converts an optical image of a subject into an electrical signal. The aspect ratio of the image sensor 22 is 3:2 or 4:3, and the longitudinal direction (X direction) of the digital camera 1 and the longitudinal direction of the image sensor 22 coincide with each other.

[0036] The A / D converter 23 converts the analog signal output from the image sensor 22 into a digital signal.

[0037] The image processing unit 24 performs predetermined pixel interpolation, resizing such as reduction, and color conversion processing on the data from the A / D converter 23 or the data from the memory control unit 15. The image processing unit 24 also performs predetermined arithmetic processing using the captured image data. Based on the arithmetic results obtained by the image processing unit 24, the system control unit 50 performs exposure control and focus detection control.

[0038] The output data from the A / D converter 23 is written into the memory 32 via the image processing unit 24 and the memory control unit 15 or via the memory control unit 15 .

[0039] The memory 32 stores image data obtained by the image sensor 22 and converted into digital data by the A / D converter 23, as well as image data to be displayed on the display unit 28 and the EVF unit 29. The memory 32 has a storage capacity sufficient to store a predetermined number of still images and a predetermined period of moving images and audio. The memory 32 also serves as a memory for displaying images (video memory).

[0040] The D / A converter 19 converts the image display data stored in the memory 32 into an analog signal and outputs it to the display unit 28 or the EVF unit 29. The display unit 28 or the EVF unit 29 displays an image according to the analog signal from the D / A converter 19 on a display such as an LCD or an organic EL.

[0041] The outside viewfinder display 43 displays the settings such as shutter speed and aperture via an outside viewfinder display drive circuit 44 .

[0042] The nonvolatile memory 56 is an electrically erasable and recordable memory, and may be, for example, an EEPROM, etc. Constants and programs for the operation of the system control unit 50 are stored in the nonvolatile memory 56.

[0043] The system control unit 50 is made up of at least one processor or circuit, and controls the entire digital camera 1. The system control unit 50 performs each process of this embodiment, which will be described later, by executing a program recorded in the nonvolatile memory 56. The system control unit 50 also performs display control by controlling the memory 32, the D / A converter 19, the display unit 28, etc.

[0044] The system memory 52 is, for example, a RAM, and stores constants and variables for the operation of the system control unit 50, programs read from the nonvolatile memory 56, and the like.

[0045] The system timer 53 measures the time used for various controls and the time of the built-in clock.

[0046] The mode changeover switch 60, the first shutter switch 62, the second shutter switch 63, and the operation unit 70 are used to input various operation instructions to the system control unit 50.

[0047] The mode selector switch 60 switches the operating mode of the system control unit 50 between a still image capture mode, a video capture mode, a playback mode, etc. Modes included in the still image capture mode include an auto capture mode, an auto scene determination mode, a manual mode, an aperture priority mode (Av mode), a shutter speed priority mode (Tv mode), and a program AE mode (P mode). There are also various scene modes and custom modes that provide capture settings for specific capture scenes. The user can directly switch to one of these modes using the mode selector switch 60. Alternatively, after switching to a list screen of capture modes using the mode selector switch 60, the user may select one of the displayed modes and then switch using other operating members. Similarly, the video capture mode may also include multiple modes.

[0048] The first shutter switch 62 is turned on and generates a first shutter switch signal SW1 when the shutter button 61 provided on the digital camera 1 is pressed halfway (a shooting preparation instruction) during operation. The system control unit 50 starts shooting preparation operations such as AF (autofocus) processing, AE (auto exposure) processing, AWB (auto white balance) processing, and EF (pre-flash) processing in response to the first shutter switch signal SW1.

[0049] The second shutter switch 63 is turned on when the shutter button 61 is fully pressed (photographing instruction) and generates a second shutter switch signal SW2. The system control unit 50 starts a series of photographing processing operations, from reading out a signal from the image sensor 22 to writing the captured image to the recording medium 200 as an image file, in response to the second shutter switch signal SW2.

[0050] The operation unit 70 is an input unit that receives operations from the user and includes the various operation members described above.

[0051] The power supply control unit 80 is composed of a battery detection circuit, a DC-DC converter, a switch circuit for switching between powered blocks, and the like, and detects whether a battery is installed, the type of battery, and the remaining battery power. The power supply control unit 80 also controls the DC-DC converter based on the detection results and instructions from the system control unit 50, and supplies the required voltage to each unit, including the recording medium 200, for the required period of time.

[0052] The power supply unit 30 includes a primary battery such as an alkaline battery or a lithium battery, a secondary battery such as an NiCd battery, an NiMH battery, or a Li battery, an AC adapter, or the like.

[0053] The recording medium I / F 18 is an interface with a recording medium 200 such as a memory card or a hard disk.

[0054] The recording medium 200 is a recording medium such as a memory card for recording captured images, and is composed of a semiconductor memory, a magnetic disk, or the like.

[0055] The communication unit 54 includes a first communication unit (first antenna) 54a and a second communication unit (second antenna) 54b, and is connected to an external device wirelessly or via a wired cable to transmit and receive video and audio signals. Specifically, the communication unit 54 can transmit images (including LV images) captured by the image sensor 22 and images recorded on the recording medium 200, and can also receive images and various other information from external devices. The communication unit 54 can also connect to a wireless LAN (Local Area Network) or the Internet, and is also compatible with MIMO (Multi-Input Multi-Output), a wireless communication technology that transmits and receives data using multiple antennas. The communication unit 54 can also communicate with external devices via Bluetooth (registered trademark) and Bluetooth Low Energy.

[0056] The shake detection unit 55 can use an acceleration sensor, a gyro sensor, or the like, and can detect movement of the digital camera 1 (such as panning, tilting, lifting, and whether the digital camera 1 is stationary). The shake detection unit 55 detects shake of the digital camera 1 in three axial directions: the pitch direction around the pitch axis of the digital camera 1, the yaw direction around the yaw axis, and the roll direction around the roll axis. The shake detection unit 55 outputs a signal (angular velocity signal) indicating the angular velocity of vibration of the digital camera 1, and the system control unit 50 calculates the magnitude of vibration of the digital camera 1 from the angular velocity signal. The system control unit 50 performs optical image shake correction (optical image stabilization) by moving the image sensor 22 in a plane perpendicular to the optical axis according to the calculated vibration amount. Based on the signal detected by the shake detection unit 55, the system control unit 50 can also determine whether an image captured by the image sensor 22 was captured with the digital camera 1 held horizontally or vertically.

[0057] The eyepiece detection unit 57 detects whether the eye (object) is approaching (approaching the eye) or moving away (moving away from the eyepiece unit 16). The system control unit 50 switches the display unit 28 and the EVF unit 29 between display (display state) and non-display (non-display state) depending on the state detected by the eyepiece detection unit 57. Specifically, at least in a shooting standby state and when the display destination switching is automatic switching, when the eye is not placed in the camera, the display destination is set to the display unit 28 and the display is turned on, and the EVF unit 29 is turned off. Furthermore, when the eye is placed in the camera, the display destination is set to the EVF unit 29 and the display is turned on, and the display unit 28 is turned off.

[0058] The touch panel 70a and the display unit 28 can be configured as an integrated unit. For example, the touch panel 70a is configured so that its light transmittance does not interfere with the display of the display unit 28, and is attached to the upper layer of the display surface of the display unit 28. Then, input coordinates on the touch panel 70a are associated with display coordinates on the display surface of the display unit 28. This makes it possible to provide a GUI (Graphical User Interface) that allows the user to directly operate the screen displayed on the display unit 28.

[0059] The holding structure of the first communication unit 54a and the second communication unit 54b in this embodiment will be described below with reference to Fig. 3. Fig. 3 is a diagram showing the structure of the top cover unit of the digital camera 1. Fig. 3(a) and Fig. 3(b) are an exploded perspective view and an assembly diagram of the top cover unit, respectively.

[0060] The top cover 90 is an exterior component molded from a conductive material such as conductive resin or magnesium alloy, and is connected with screws 99 to a main chassis 160 (shown in Figure 11) molded from a conductive material such as conductive resin or magnesium alloy.

[0061] The antenna cover 91 is molded from a non-conductive resin material and is a cover member that covers a part of the top cover 90. The antenna cover 91 is fixed to the upper part of the top cover 90 with screws 99. A space is formed between the top cover 90 and the antenna cover 91 to accommodate the first communication unit 54a and the second communication unit 54b.

[0062] The first communication unit 54a and the second communication unit 54b are included in the communication unit 54 and are configured to be able to communicate wirelessly. The first communication unit 54a and the second communication unit 54b are disposed at positions away from the center of the optical axis of the image sensor 22 and closer to the subject than the eyepiece 16 (EVF unit 29) through which the user views the subject.

[0063] The first communication unit 54a is arranged so that the substrate surface (first surface) on which the antenna pattern (first pattern) is wired is perpendicular to the optical axis direction (Z direction). The first communication unit 54a is also arranged so that the longitudinal direction of the antenna pattern is the same as the longitudinal direction (X direction) of the digital camera 1 (image sensor 22). Here, "perpendicular" includes not only "strictly perpendicular" but also "substantially perpendicular (approximately perpendicular)." Furthermore, "identical" includes not only "strictly identical" but also "substantially identical (approximately identical)."

[0064] The second communication unit 54b is disposed such that the substrate surface (second surface) on which the antenna pattern (second pattern) is wired is inclined relative to the direction perpendicular to the optical axis direction (Y-axis direction) with respect to the first communication unit 54a. The inclination angle may be any angle that allows a correlation coefficient (described later) to have a value that satisfies communication performance, and is, for example, 90 degrees ± 30 degrees. The inclination angle is preferably 90 degrees ± 10 degrees, and more preferably 90 degrees. Here, 90 degrees includes not only the case where it is exactly 90 degrees, but also the case where it is substantially 90 degrees (approximately 90 degrees). In this embodiment, the second communication unit 54b is disposed such that it is inclined 90 degrees relative to the Y-axis direction with respect to the first communication unit 54a. The second communication unit 54b is disposed such that the longitudinal direction of the antenna pattern is the same as the longitudinal direction of the digital camera 1 (image sensor 22).

[0065] Furthermore, shake detection unit 55 is housed in an area where directions (Z-axis direction and Y-axis direction) perpendicular to the board surfaces of first communication unit 54a and second communication unit 54b intersect, further inside (negative Y-axis side) of the space housing first communication unit 54a and second communication unit 54b. This makes it possible to house the antenna efficiently inside digital camera 1.

[0066] The antenna fixing member 92 is a non-conductive member molded from a non-conductive resin material. The conductive plate 93 is a sheet metal member made of a conductive material such as an aluminum alloy, stainless steel, or copper plate. The conductive plate 93 is disposed between the antenna fixing member 92 and the first and second communication units 54a and 54b, and is fixed with screws 99. The conductive plate 93 is electrically connected to the ground patterns 548 (shown in FIG. 5 ) of the first and second communication units 54a and 54b. The conductive plate 93, the first and second communication units 54a, and 54b are fastened to the top cover 90 with screws 99, and are electrically connected to the top cover 90.

[0067] Hereinafter, a configuration (antenna unit) in which the first communication unit 54a and the second communication unit 54b are attached to the antenna fixing member 92 of this embodiment will be described with reference to Fig. 4. Fig. 4 is a diagram showing a holding configuration for the first communication unit 54a and the second communication unit 54b.

[0068] The first communication unit 54a and the second communication unit 54b include coaxial cables 541a and 541b, respectively. Coaxial connectors 542a and 542b are provided at the ends of the coaxial cables 541a and 541b, respectively. The coaxial connectors 542a and 542b are connected to a main board (not shown) (system control unit 50), allowing the system control unit 50 to perform desired communication and control. The coaxial cable holding member 94 is molded from non-conductive resin and is used to attach the coaxial cables 541a and 541b to the top cover 90. The coaxial cable 541a is wired between the top cover 90 and the coaxial cable holding member 94. The coaxial cable 541b is wired to the coaxial cable holding member 94 so that it does not fall off the coaxial cable holding member 94 due to its own weight.

[0069] Coaxial cables are noise-resistant electrical cables, with the conductor wire through which the signal passes covered in an insulator, which is then covered in a ground (GND) conductor. However, if multiple coaxial cables run parallel to each other over a long distance while touching each other, there is a possibility that the signals from both cables may cause radio wave interference. Therefore, it is desirable to install a coaxial cable holding member 94 between coaxial cables 541a and 541b to prevent the coaxial cables from touching each other. This improves the shielding effect of the coaxial cables and reduces the risk of radio wave interference between the coaxial cables.

[0070] The configuration of the antenna of this embodiment will be described below with reference to Fig. 5. Fig. 5 is a diagram showing the antenna configuration of the communication unit 54, and is a front view of a substrate on which an antenna pattern is wired.

[0071] The communication unit 54 transmits a signal from a main board (not shown) through a coaxial cable 541, and transmits the signal to a matching component 543 of the communication unit 54 via a solder joint 547. A ground shield portion covering the outer periphery of the coaxial cable 541 is connected to a ground pattern 548 via the solder joint 547.

[0072] The matching component 543 adjusts the signal (current) transmitted through the coaxial cable 541 so that the antenna impedance has a desired value. By adjusting the antenna impedance using the matching component 543, it is possible to make the transmitted signal (current) less likely to be reflected. For example, even if the first communication unit 54a and the second communication unit 54b have the same pattern and the same board layer configuration, it is desirable to set the matching component 543 to an optimal impedance value depending on the installation location.

[0073] First transmitting unit 545 and second transmitting unit 546 are oscillation points that oscillate the current supplied to power supply unit 544 as radio waves.

[0074] The power supply pattern 550 is an antenna pattern that supplies current from the power supply section 544 to the first transmitting section 545 and the second transmitting section 546 .

[0075] The first antenna pattern 551 is an antenna pattern extending from the power supply pattern 550 to the first transmitting unit 545, and has a wiring length suitable for the 2.4 GHz frequency band.

[0076] The second antenna pattern 552 is an antenna pattern extending from the power supply pattern 550 to the second transmitting unit 546, and has a wiring length suitable for the 5.0 GHz frequency band.

[0077] Ground connection portion 549 is a hole that penetrates the board and is used to connect communication portion 54 to top cover 90 with screws 99. Top cover 90 is connected to main chassis 160 (shown in FIG. 11) with screws 99. Since main chassis 160 connects to all conductive members of digital camera 1, ground pattern 548 has electrical characteristics that are so-called earth.

[0078] The length of the antenna pattern from power supply 544 to first transmitting unit 545 and the length of the antenna pattern from power supply 544 to second transmitting unit 546 are λ / 4, where λ is the wavelength of the radio wave of the set frequency. When the set frequency is f and the propagation speed is v, the length of the antenna pattern can be calculated using the following formula.

[0079]

number

[0080] In this embodiment, the communication unit 54 includes two antennas, one for 2.4 GHz and one for 5.0 GHz. Each antenna is a so-called monopole antenna, with a first end connected to ground. A monopole antenna can be designed with a length of λ / 4, which is half the length of a typical dipole antenna, λ / 2, and therefore the communication unit 54 can be designed to be compact.

[0081] The distance between the antenna patterns of the first communication unit 54a and the second communication unit 54b and the mounting configuration will be described below with reference to Fig. 6. Fig. 6 is a diagram showing the holding configuration of the communication unit 54. Fig. 6(a) is a front view of the antenna unit of Fig. 4. Fig. 6(b) is a cross-sectional view taken along line AA of Fig. 6(a). The position of line AA is the same as the cross-sectional position of Fig. 3(a).

[0082] The first communication unit 54a and the second communication unit 54b have the same configuration as the communication unit 54 described in FIG. 5. When the power supply pattern 550, the first antenna pattern 551, and the second antenna pattern 552 are attached at the position of the first communication unit 54a in FIG. 6(b), the suffix "a" is added to the end of their respective numbers. Specifically, the power supply pattern 550a, the first antenna pattern 551a, and the second antenna pattern 552a are referred to as the power supply pattern 550a, the first antenna pattern 551a, and the second antenna pattern 552a, respectively, and the description continues. The power supply pattern 550a, the first antenna pattern 551a, and the second antenna pattern 552a constitute a first pattern formed on the first communication unit 54a. Similarly, when the communication unit 54 is attached at the position of the second communication unit 54b, the suffix "b" is added to the end of their respective numbers. Specifically, the power supply pattern 550b, the first antenna pattern 551b, and the second antenna pattern 552b are referred to as the power supply pattern 550b, the first antenna pattern 551b, and the second antenna pattern 552b, respectively, and the description continues. The power supply pattern 550b, the first antenna pattern 551b, and the second antenna pattern 552b constitute a second pattern formed in the second communication unit 54b.

[0083] The spatial distance L1 is the distance between a first antenna pattern 551a included in the first pattern formed in the first communication unit 54a and a first antenna pattern 551b included in the second pattern formed in the second communication unit 54b. The spatial distance L2 is the distance between a second antenna pattern 552a included in the first pattern formed in the first communication unit 54a and a second antenna pattern 552b included in the second pattern formed in the second communication unit 54b.

[0084] As described above, the first antenna patterns 551a and 551b are antenna patterns suitable for 5.0 GHz, and the second antenna patterns 552a and 552b are antenna patterns suitable for 2.4 GHz.

[0085] Generally, when arranging multiple antennas, it is desirable to space them apart by a distance of λ / 2 (λ / 4 in the case of monopole antennas). That is, based on the relationship between frequency f, propagation speed v, and wavelength λ, it is desirable to space them apart by 31.25 mm (=λ / 4) for 2.4 GHz and 15 mm (=λ / 4) or more for 5.0 GHz. However, in this case, the antennas would not fit in the space between the top cover 90 and the antenna cover 91, and the size of the digital camera 1 would increase.

[0086] Therefore, in this embodiment, the spatial distance L1 between the first antenna patterns is set to approximately 10 mm (=λ / 6), and the spatial distance L2 between the second antenna patterns is set to approximately 10 mm (=λ / 12.5). If the spatial distances L1 and L2 are too close, the correlation coefficient becomes 1, and different antennas will oscillate as if they were the same antenna.

[0087] Hereinafter, the correlation coefficient when the first communication unit 54a and the second communication unit 54b are suitably arranged will be described with reference to Fig. 7. Fig. 7 is a diagram showing the correlation coefficient between the first communication unit 54a and the second communication unit 54b. The horizontal axis of Fig. 7 represents frequency, and the vertical axis represents the correlation coefficient.

[0088] When the correlation coefficient approaches 1, electromagnetic coupling occurs even between different communication units (antennas), reducing antenna efficiency. This reduces communication distance and communication capacity, preventing MIMO from functioning. Therefore, the closer the correlation coefficient is to 0, the better the MIMO communication efficiency. In this embodiment, multiple communication units are arranged close to each other and are arranged to fulfill MIMO functionality.

[0089] The correlation coefficient 213 between the first communication unit 54a and the second communication unit 54b is approximately 0.3 in the 2.4 GHz frequency band widely used in the I-Triple-E 802 standard (hereinafter referred to as the IEEE 802 standard). The correlation coefficient 213 is approximately 0.3 or less in a frequency band 211 of 5.0 GHz or higher corresponding to IEEE 802.11n / 11ac / 11ax. 212 indicates the range of the correlation coefficient 0.3±10%. In this way, the first communication unit 54a and the second communication unit 54b function normally as independent antennas in MIMO.

[0090] In the case of monopole antennas, the first communication unit 54a and the second communication unit 54b are preferably spaced apart by at least λ / 4. However, as mentioned above, even if the spatial distance L1 between the antennas compatible with 5.0 GHz is set to λ / 6 and the spatial distance L2 between the antennas compatible with 2.4 GHz is set to λ / 12.5, the correlation coefficient is approximately 0.3, and the antennas operate independently. In this way, by arranging the first communication unit 54a and the second communication unit 54b at a distance shorter than the generally required λ / 4, it is possible to prevent the digital camera 1 from becoming larger. Furthermore, even in MIMO communication, communication that is practically usable can be performed without significantly reducing the amount of data handled in a certain period of time.

[0091] If priority is given to not increasing the size of the digital camera 1, it is desirable to set the spatial distance L1 between antennas compatible with the 5.0 GHz band to λ / 6, and the spatial distance L2 between antennas compatible with the 2.4 GHz band to λ / 12.5. However, this does not apply if priority is given to the correlation coefficient (i.e., the correlation coefficient is set to 0.3 or less). For example, the spatial distance L1 may be set in the range from λ / 6 to λ / 4, and the spatial distance L2 may be set in the range from λ / 12.5 to λ / 4.

[0092] 8, a description will be given of a configuration in which the first communication unit 54a and the second communication unit 54b are housed in the space between the top cover 90 and the antenna cover 91. FIG. 8 is a cross-sectional view taken along line AA in FIG. 3(a), and shows the cross-sectional configuration of the top cover 90.

[0093] If the first communication unit 54a and the second communication unit 54b are positioned with their antennas randomly spaced apart, they cannot be completely covered by the antenna cover 91, which increases the size of the antenna cover 91 and the overall size of the digital camera 1.

[0094] In this embodiment, the first communication unit 54a is positioned so that the substrate surface on which the antenna pattern is wired is perpendicular to the optical axis direction and the longitudinal direction of the antenna pattern is the same as the longitudinal direction of the digital camera 1 (image sensor 22).

[0095] In addition, the second communication unit 54b is positioned so that the substrate surface on which the antenna pattern is wired is tilted 90 degrees relative to the direction perpendicular to the optical axis direction, with the first communication unit 54a as the reference, and so that the longitudinal direction of the antenna pattern is the same as the longitudinal direction of the digital camera 1 (image sensor 22).

[0096] The first and second communication units 54a and 54b are arranged so that the boards of the second and first communication units 54b and 54a do not overlap on an extension of the board projection plane of the first and second communication units 54a and 54b, respectively. In other words, the first and second communication units 54a and 54b are arranged so that they do not overlap when viewed in directions (Z-axis direction and Y-axis direction) perpendicular to each other's board plane. In this embodiment, by arranging the shake detection unit 55 inside the first and second communication units 54a and 54b, it is possible to efficiently accommodate the shake detection unit 55 and the communication unit 54 in the digital camera 1 in a space closer to the subject than the eyepiece unit 16 (EVF unit 29).

[0097] Here, we will explain the polarization direction of the radio waves (electromagnetic waves) transmitted and received by the communication unit 54. Generally, electromagnetic waves are divided into vertically polarized waves that move vertically and horizontally polarized waves that move horizontally according to the vibration of the electric field propagating through space. If the polarization directions of transmitted and received waves do not match, the antenna will not be able to communicate data effectively, resulting in reduced communication efficiency.

[0098] In this embodiment, by arranging the second communication unit 54b at an angle with respect to the first communication unit 54a, the polarization directions of the first communication unit 54a and the second communication unit 54b can be changed, thereby reducing the correlation coefficient. Therefore, even in MIMO, communication can be performed without significantly reducing the amount of data handled in a certain period of time.

[0099] 9, an example of how a user holds the digital camera 1 and photographs a subject is illustrated, and it is explained that the first communication unit 54a and the second communication unit 54b are unlikely to be covered by the hand. FIG. 9 is a diagram showing an example of a posture in which the digital camera 1 is held. FIG. 9(a) is a front view of the digital camera 1 held horizontally by the user. FIG. 9(b) is a side view of the digital camera 1 held horizontally by the user. FIG. 9(c) is a front view of the digital camera 1 held vertically by the user. FIG. 9(d) is a side view of the digital camera 1 held vertically by the user.

[0100] A typical posture for a user taking a photograph is to hold grip portion 82 with the right hand, lens unit 150 with the left hand, and look into the viewfinder (eyepiece portion 16).

[0101] 9(a) and 9(b), the position of the communication unit 54 is at a position on the top of the digital camera 1 that is unlikely to be covered by the user's hands or face. In addition, in FIGS. 9(c) and 9(d), the position of the communication unit 54 is at a position on the side of the digital camera 1 that is unlikely to be covered by the user's hands or face.

[0102] In this way, the communication unit 54, which is located away from the center of the optical axis of the digital camera 1 and is located closer to the subject than the eyepiece 16, is located in a place that is unlikely to be covered by the user's hands or face, allowing for good wireless communication during shooting. (Second embodiment) In the first embodiment, we described a case where multiple communication units are arranged inside the top cover 90, away from the center of the optical axis of the image sensor 22 and closer to the subject than the eyepiece 16, so that they are unlikely to be covered by the user's hands or face when the user holds the digital camera 1 to take a picture.

[0103] In this embodiment, a configuration is described that enables good MIMO communication using multiple communication units without increasing the size of the digital camera 1 in shooting situations where the user is not holding the digital camera 1.

[0104] The spatial distance and holding angle between the antenna patterns of the first communication unit 54a and the second communication unit 54b are the same as those in the first embodiment. In this embodiment, only the configurations different from those in the first embodiment will be described, and a description of the common configurations will be omitted.

[0105] 10 is a diagram showing digital camera 1 attached to tripod 190. When taking pictures using digital camera 1, the user may attach digital camera 1 to a tripod or head rather than holding it in his or her hand, and take pictures using a remote control or wireless communication. In this case, by locating communication unit 54 in grip portion 82 that protrudes from inside digital camera 1, good wireless communication can be achieved without radio waves being blocked by the metal exterior of digital camera 1 itself or lens unit 150.

[0106] FIG. 11 is an explanatory diagram of a case where the first communication unit 54a and the second communication unit 54b are attached to the grip unit 82. As shown in FIG.

[0107] The main chassis 160 is molded from a conductive material such as conductive resin or magnesium alloy, and a battery 203 is housed inside the main chassis 160 .

[0108] The front cover 180 is molded from a non-conductive resin material and is fixed to the main chassis 160 with screws (not shown). A space is formed between the main chassis 160 and the front cover 180 to accommodate the first communication unit 54a and the second communication unit 54b.

[0109] The first communication unit 54a and the second communication unit 54b are directly fixed to the main chassis 160 by screws 99. The ground pattern 548 of the communication unit 54 is connected to a conductive member of the digital camera 1, and has electrical characteristics as a so-called earth.

[0110] Bottom cover 170 is molded from a non-conductive resin material and is an exterior part used when fixing digital camera 1 to a tripod 190 or a platform (not shown). Bottom cover 170 includes a battery cover 204 from which battery 203 can be removed.

[0111] The first and second communication units 54a, 54b are arranged at approximately 90 degrees from each other so that the boards of the second and first communication units 54b, 54a do not overlap on extensions of the board projection surfaces of the first and second communication units 54a, 54b. In this case, by accommodating the battery 203 inside the first communication unit 54a and the second communication unit 54b, it is possible to efficiently arrange the first communication unit 54a and the second communication unit 54b in the space formed between the main chassis 160 and the front cover 180.

[0112] Furthermore, by arranging the first communication unit 54a and the second communication unit 54b at an angle of 90 degrees, the polarization directions of the first communication unit 54a and the second communication unit 54b can be changed, thereby reducing the correlation coefficient. Therefore, even in MIMO, communication can be performed without significantly reducing the amount of data handled in a certain period of time. (Third embodiment) In this embodiment, as in the first embodiment, a configuration will be described in which multiple communication units are arranged inside the top cover 90 on the subject side of the eyepiece 16, which is less likely to be covered by the user's hands or face when holding the digital camera 1 to take a picture. In particular, an antenna mounting configuration will be described in which the antennas are arranged in a twisted direction and the polarization directions (vertical polarization and horizontal polarization) are changed to further improve the correlation coefficient between the antennas. Note that in this embodiment, only configurations that are different from the first embodiment will be described, and a description of common configurations will be omitted.

[0113] FIG. 12 is an exploded perspective view showing the configuration of the imaging device of the third embodiment.

[0114] The top cover 90 is molded from a conductive material such as conductive resin or magnesium alloy, and is connected with screws 99 to a main chassis 160 (shown in Figure 11) that is also molded from a conductive material such as conductive resin or magnesium alloy.

[0115] The antenna cover 91 is molded from a non-conductive resin material and fixed to the top of the top cover 90 with screws 99. A space is formed between the top cover 90 and the antenna cover 91 to accommodate the first communication unit 54a and the second communication unit 54b.

[0116] The first communication unit 54a and the second communication unit 54b enable wireless communication and are arranged closer to the subject than the eyepiece unit 16 through which the user views the subject.

[0117] The first communication unit 54a is arranged so that the substrate surface on which the antenna pattern is wired is perpendicular to the optical axis direction and its longitudinal direction is the same as the longitudinal direction of the digital camera 1 (imaging element 22).

[0118] The second communication unit 54b is disposed such that the substrate surface on which the antenna pattern is wired is inclined by 90 degrees relative to the first communication unit 54a in the direction perpendicular to the optical axis direction (X-axis direction), and the longitudinal direction of the antenna pattern is aligned with the optical axis direction. The relationship between the first communication unit 54a and the second communication unit 54b may be a twisted relationship.

[0119] By accommodating the shake detection unit 55 further inside the space that accommodates the first communication unit 54a and the second communication unit 54b, the communication unit 54 and the shake detection unit 55 can be efficiently accommodated within the digital camera 1.

[0120] Generally, the polarization direction is determined according to the direction of the current flowing through the antenna, so the polarization plane can be changed by tilting it by 90 degrees. In this embodiment, the correlation coefficient can be improved by setting the longitudinal direction of the antenna pattern of the first communication unit 54a to the X-axis direction and the longitudinal direction of the antenna pattern of the second communication unit 54b to the Z-axis direction.

[0121] The antenna fixing member 92 is a non-conductive member molded from a non-conductive resin material. The conductive plate 93 is a sheet metal member made of a conductive material such as aluminum alloy, stainless steel, or copper plate. The conductive plate 93 is disposed between the antenna fixing member 92 and the first communication unit 54a and is fixed with screws 99 on the upper surface of the first communication unit 54a. At this time, the conductive plate 93 is electrically connected to the first communication unit 54a. When fastened to the top cover 90 with the screws 99, the conductive plate 93 and the first communication unit 54a are electrically connected to the top cover 90. Similarly, the second communication unit 54b is fixed to the top cover 90 with the screws 99 and is electrically connected to the top cover 90.

[0122] The disclosure of this embodiment includes the following configuration. (Configuration 1) a first member made of a conductive member; a second member made of a non-conductive material; a first antenna and a second antenna that are disposed between the first member and the second member and are capable of wireless communication; the first antenna has a first surface on which a first pattern is formed and which is orthogonal to an optical axis direction; the second antenna has a second surface on which a second pattern is formed and which is inclined relative to the first surface; An imaging device characterized in that the first antenna and the second antenna are arranged so that they do not overlap each other when viewed from the optical axis direction and when viewed from a direction perpendicular to the second surface. (Configuration 2) 2. The imaging device according to configuration 1, wherein the second surface is inclined at 90 degrees relative to the first surface. (Configuration 3) further comprising an image sensor that converts an optical image of a subject into an electrical signal; a longitudinal direction of the first pattern and a longitudinal direction of the imaging element are the same; 3. The imaging device according to configuration 2, wherein the longitudinal direction of the second pattern is the same as the longitudinal direction of the imaging element. (Configuration 4) further comprising an image sensor that converts an optical image of a subject into an electrical signal; a longitudinal direction of the first pattern and a longitudinal direction of the imaging element are the same; 3. The imaging device according to configuration 2, wherein the longitudinal direction of the second pattern is the same as the optical axis direction. (Configuration 5) the first member is an exterior member, 5. The imaging device according to any one of configurations 1 to 4, wherein the second member is an exterior member that covers a part of the first member. (Configuration 6) Further comprising an eyepiece, The imaging device according to configuration 5, wherein the first and second antennas are arranged closer to the subject than the eyepiece. (Configuration 7) 7. The imaging device according to configuration 5 or 6, further comprising a shake detection unit disposed in a region where the optical axis direction intersects with a direction perpendicular to the second surface. (Configuration 8) the first member is a member for fixing the first and second antennas, 3. The imaging device according to configuration 1 or 2, wherein the second member is an exterior member having a grip portion for a photographer to grip the imaging device. (Configuration 9) 9. The imaging device according to configuration 8, further comprising a battery disposed in a region where the optical axis direction intersects with a direction perpendicular to the second surface. (Configuration 10) 10. The imaging device according to any one of configurations 1 to 9, wherein the first and second patterns include a first antenna pattern and a second antenna pattern, each tuned to a different frequency. (Configuration 11) When the wavelength of the radio wave of the set frequency is λ, the distance between the first antenna patterns is in the range of λ / 6 to λ / 4; 11. The imaging device according to claim 10, wherein the distance between the second antenna patterns is in the range of λ / 12.5 to λ / 4. (Configuration 12) 12. The imaging device according to any one of configurations 1 to 11, wherein the first and second communication units are monopole antennas.

[0123] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention. (Explanation of symbols) 1. Digital camera (imaging device) 54a First communication unit (first antenna) 54b Second communication unit (second antenna) 90 Top cover (first component) 91 Antenna cover (secondary component) 160 Main chassis (first component) 189 Front cover (second part) 550a First antenna pattern (first pattern) 551a Power supply pattern (first pattern) 552a Second antenna pattern (first pattern) 550b First antenna pattern (second antenna pattern) 551b Feed pattern (second antenna pattern) 552b Second Antenna Pattern (Second Pattern)

Claims

1. a first member made of a conductive member; a second member made of a non-conductive material; a first antenna and a second antenna that are disposed between the first member and the second member and are capable of wireless communication; the first antenna has a first surface on which a first pattern is formed and which is orthogonal to an optical axis direction; the second antenna has a second surface on which a second pattern is formed and which is inclined relative to the first surface; An imaging device characterized in that the first antenna and the second antenna are arranged so that they do not overlap each other when viewed from the optical axis direction and when viewed from a direction perpendicular to the second surface.

2. 2. The imaging device according to claim 1, wherein the second surface is inclined at 90 degrees with respect to the first surface.

3. further comprising an image sensor that converts an optical image of a subject into an electrical signal; a longitudinal direction of the first pattern and a longitudinal direction of the imaging element are the same; 3. The imaging device according to claim 2, wherein the longitudinal direction of the second pattern is the same as the longitudinal direction of the imaging element.

4. further comprising an image sensor that converts an optical image of a subject into an electrical signal; a longitudinal direction of the first pattern and a longitudinal direction of the imaging element are the same; 3. The imaging device according to claim 2, wherein the longitudinal direction of the second pattern is the same as the optical axis direction.

5. the first member is an exterior member, 3. The imaging device according to claim 1, wherein the second member is an exterior member that covers a part of the first member.

6. Further comprising an eyepiece, 6. The imaging device according to claim 5, wherein the first and second antennas are arranged closer to the subject than the eyepiece.

7. 6. The imaging device according to claim 5, further comprising a vibration detection unit disposed in a region where the optical axis direction intersects with a direction perpendicular to the second surface.

8. the first member is a member for fixing the first and second antennas, 3. The imaging device according to claim 1, wherein the second member is an exterior member having a grip portion for a photographer to grip the imaging device.

9. 9. The imaging device according to claim 8, further comprising a battery disposed in a region where the optical axis direction intersects with a direction perpendicular to the second surface.

10. 3. The imaging device according to claim 1, wherein the first and second patterns include a first antenna pattern and a second antenna pattern, each tuned to a different frequency.

11. When the wavelength of the radio wave of the set frequency is λ, the distance between the first antenna patterns is in the range of λ / 6 to λ / 4; 11. The imaging device according to claim 10, wherein the distance between the second antenna patterns is in the range of λ / 12.5 to λ / 4.

12. 3. The imaging device according to claim 1, wherein the first and second antennas are monopole antennas.

Images