JP2019023683A - Imaging device - Google Patents

Abstract

To solve the problem in which: in an imaging device including a converter lens, sunlight and the like is condensed on an imaging element and the imaging element is burned even when an interchangeable lens is not attached to the imaging device.SOLUTION: An imaging device 1 arranges a first polarization filter 105 and a second polarization filter 106 between a lens mount part 101 and an imaging element 110 and on an optical axis 149. The first polarization filter 105 is rotated in mechanical linkage to attachment/detachment rotation operation of an interchangeable lens 2. The imaging device 1 can thus attenuate light entering the imaging element 110 and can prevent burning of the imaging element 110.SELECTED DRAWING: Figure 4b

Description

  The present invention relates to prevention of burning of an image pickup element of an image pickup apparatus such as an interchangeable lens video camera.

  In an imaging apparatus such as an interchangeable lens video camera, a technique for miniaturizing an imaging element such as a CCD or a CMOS is taken with the aim of miniaturization. For this reason, an image sensor having a size smaller than the widely used image sensor size may be mounted. However, when an image is taken with an interchangeable lens made for the size of the imaging element that is widely used in these video cameras, only a part of the light beam of the interchangeable lens is received by the imaging device, so it is widely used. There is a problem that the angle of view becomes narrower than that of a camera equipped with an imaging device.

  In order to widen the angle of view, a technique of providing a converter lens in the camera body has been conventionally known. The converter lens not only widens the angle of view, but also reduces the F value of the entire optical system including the interchangeable lens and the converter lens, thereby enabling bright shooting. Capturing brightly has the advantage that ISO sensitivity can be suppressed even when the shooting environment is dark, and shooting can be performed with less noise.

  However, in an imaging apparatus including a converter lens, there is a problem that sunlight or the like is concentrated on the imaging element and the imaging element is burned even when the interchangeable lens is not attached to the imaging apparatus.

  Therefore, for the conventional image sensor burn problem, two polarizing filters are arranged on the optical axis between the interchangeable lens and the image sensor, and one of the two filters is driven by an electric motor or the like. Therefore, there is an object that attenuates sunlight and the like as polarized ND (Neutral Density). For example, Patent Document 1.

JP 2013-109008 A

However, in the above conventional example, since the polarizing filter is driven by an electric motor or the like, there is a problem that the image pickup device cannot be prevented from being burned when the image pickup device is not energized, such as when an interchangeable lens is detached from the image pickup device. .

In the imaging apparatus 1 having the bayonet-type interchangeable lens 2 and the lens mount portion 101 corresponding to the bayonet,
A first polarizing filter 105 and a second polarizing filter 106 between the lens mount unit 101 and the image sensor 110 and on the optical axis 149;
A two-stage spur gear 141 composed of a large-diameter gear and a small-diameter gear, a biasing member 143 that urges the two-stage spur gear 141, and an internal gear that rotates about the optical axis 149 are provided at locations not on the optical axis 149. 142, an abutting portion 144 which is a mechanical end of the internal gear 142, and a lock portion 104 disposed on the lens mount portion 101,
The interchangeable lens 2 has a bayonet claw portion 150, a contact portion 151 that is a part of the bayonet claw portion 150, and a concave portion 152 that holds the interchangeable lens 2 by being combined with the lock portion 104,
The internal gear 142 has a contact portion 145 that contacts a contact portion 151 that is a part of the bayonet claw portion 150 when the interchangeable lens 2 is rotationally attached and detached.
The outer periphery of the first polarizing filter 105 has a spur gear shape,
The spur gear on the outer periphery of the first polarizing filter 105 meshes with the large-diameter spur gear of the two-stage spur gear 141,
The small-diameter two-stage spur gear 141 meshes with the internal gear 142,
The two-stage spur gear 141 is urged in the rotational direction of the gear by the urging member 143,
The internal gear 142 always urges the bayonet claw 150 of the interchangeable lens 2 in the rotational direction to remove it,
When the interchangeable lens 2 is attached to the lens mount portion 101, the biasing force of the internal gear 142 is one part of the bayonet claw portion 150 via a contact portion 145 that is a part of the internal gear 142. The contact portion 151, which reaches the recess portion 152 through the bayonet claw portion 150, and is received by the lock portion 104,
When the interchangeable lens 2 is not attached, the urging force of the internal gear 142 is received by the abutting portion 144,
When the interchangeable lens 2 is attached to the lens mount 101, the polarization directions of the first polarizing filter 105 and the second polarizing filter 106 are substantially parallel,
When the interchangeable lens 2 is not attached, the polarization directions of the first polarizing filter 105 and the second polarizing filter 106 are not substantially parallel.

  As described above, according to the present invention, even when the imaging apparatus is not energized, the effect of preventing the image sensor from burning can be obtained.

It is an external appearance perspective view of the state which attached the interchangeable lens 2 to the imaging device 1 which concerns on embodiment of this invention. It is an external appearance perspective view of the state which removed interchangeable lens 2 of imaging device 1 concerning an embodiment of the present invention. 1 is a block diagram illustrating a configuration of an imaging apparatus 1 according to an embodiment of the present invention. It is a disassembled perspective view which shows the main structures of the imaging device 1 which concerns on the implementation type | system | group of this invention. FIG. 4b is a perspective view of the assembled state of FIG. 4a. 2 is a perspective view showing a bayonet structure of an interchangeable lens 2 that can be attached to the imaging apparatus 1. FIG. The mechanical connection from the contact part 145 which is a part of the internal gear 142 which contacts the contact part 151 to the first polarizing filter 105 is shown, and the mechanical connection between the electric motor 146 and the second polarizing filter 106 is shown. FIG. FIG. 6b is a cross-sectional perspective view of FIG. 6a for explaining the mechanical connection of FIG. 6a. The interchangeable lens 2 is attached to the imaging device 1, and the abutment portion 151 that is a part of the bayonet claw 150 of the interchangeable lens 2 abuts on a contact portion 145 that is a part of the internal gear 142. FIG.

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

  FIG. 1 is an external perspective view of an imaging apparatus 1 according to an embodiment of the present invention. In particular, FIG. 1A is an external perspective view of the imaging device 1 viewed from the subject side on the upper surface, and FIG. 1B is an external perspective view viewed from the photographer side of the upper surface. FIG. 2 is an external perspective view of the imaging apparatus 1 with the interchangeable lens 2 removed.

The imaging device 1 is configured as a lens interchangeable digital video camera. FIG.
As shown in FIG. 2, the imaging apparatus 1 includes a bayonet type interchangeable lens 2 and a lens mount portion 101 corresponding to the bayonet.
In addition, a converter lens 102 described later is provided between the lens mount unit 101 and the image sensor 110 described later and on an optical axis 149 connecting the lens mount unit 101 and the center of the image sensor 110.

  Further, a first polarizing filter 105 and a second polarizing filter 106 described later are provided between the lens mount unit 101 and the image sensor 110 and on the optical axis 149. In addition, when the interchangeable lens 2 is attached to the imaging device 1 on the lens mount unit 101, a lens release button 124 that has a lock unit 104 for holding the interchangeable lens 2 and is integrated with the lock unit 104 is provided. When the lens release button 124 is pressed by an urging member (not shown), the lock unit 104 moves in conjunction with it, and the lock is released from the recess 152 shown later, and the interchangeable lens 2 can be rotated and detached.

  There are a power button 120 and a REC button 121 on the left side when the imaging apparatus 1 is viewed from the subject side. When the power button 120 is pushed in from the power-off state, the power is turned on, and photographing is possible. When the power is turned on, a shooting through image is displayed on the display panel 131 of the panel unit 130 installed on the back side of the imaging apparatus 1. On the left side of the imaging device 1 as viewed from the subject, there is a rotary dial 122, and the setting F value can be changed by rotating the rotary dial 122. In addition, a mode selection dial 123 is provided at this place, and the photographing mode can be changed by rotating.

  The imaging device 1 is configured to reduce the light beam by about 0.65 times by the converter lens 102 and form an image on the 1 Inch type imaging device 110 of about 13.2 mm × about 8.8 mm.

  FIG. 3 is a block diagram showing a configuration of the imaging apparatus 1 according to the embodiment of the present invention. By operating the power button 120, the imaging device 1 pushes the power switch 301, and the signal is sent to the control IC 351. The imaging device 1 is turned on and enters a standby state. When the REC button 121 is pressed in this state, the REC switch 302 detects this operation, REC is started, and writing of the digital video data to the recording unit 140 is started. When the REC button 121 is pressed again in this state, the REC is terminated, the standby state is restored, and the writing of the digital video data to the recording unit 140 is completed.

  The imaging apparatus 1 includes an electronic contact portion 103 that performs data communication with the interchangeable lens 2. The electronic contact unit 103 performs data communication such as transmission of power to the interchangeable lens 2, reception of lens identification information from the interchangeable lens 2, and transmission of autofocus and F value control signals to the interchangeable lens 2. When the power of the imaging device 1 is turned on with the interchangeable lens 2 mounted, or when the interchangeable lens 2 is mounted with the power of the imaging device 1 turned on, the interchangeable lens is first passed through the electronic contact portion 103. 2 is supplied with electric power. The interchangeable lens 2 supplied with power is controlled to send lens identification information of the interchangeable lens 2 to the imaging apparatus 1.

  The lens identification information received from the electronic contact unit 103 is sent to the control IC 351. The control IC 351 that has received this information finds equivalent lens identification information from the lens identification information group stored in advance in the program memory unit 311. When the equivalent lens identification information is found, the control IC 351 receives information on the limit F value associated with the lens identification information from the program memory unit 311. The information on the limit F value is information on the lowest value of the F value in which the peripheral light amount drop does not stand out after the imaging device 1 including the converter lens 102 corrects the peripheral light amount. The control IC 351 that has received the information on the limit F value sends a control signal that is set to be equal to or greater than the limit F value to the interchangeable lens 2 through the electronic contact portion 103 to control the F value.

  The F value can be changed by operating the rotary dial 122. When the rotary dial 122 is turned in the standby state or REC, the rotary dial detection switch 303 detects the operation. The rotary dial detection switch 303 sends the signal to the control IC 351, and the control IC 351 can change the F value in accordance with the rotation amount of the rotary dial 122 within the range of the F value equal to or higher than the limit F value.

  The subject image formed through the interchangeable lens 2 and the converter lens 102 is converted into an electric signal by the image sensor 110. The converted signal is input to the control unit 350 of the main board 310. The control unit 350 includes an image processing unit 352 that converts signal charges sent from the image sensor 110 into digital video data of luminance and color signals, a control IC 351 that is a CPU, and a work memory unit 353 that is a volatile memory. Is done.

  The control IC 351 receives the peripheral light amount correction data associated with the lens identification information group from the program memory unit 311 and sends the peripheral light amount correction data to the image processing unit 352. The image processing unit 352 performs peripheral light amount correction on the electrical signal sent from the image sensor 110 based on the peripheral light amount correction data, and then converts it into digital video data. The converted digital video data is temporarily recorded in the work memory unit 353 and is recorded in the recording unit 140 under the control of the control IC 351. The digital video data is sent from the image processing unit 352 to the panel image processing unit 132 in the panel unit 130.

  The sent digital video data is converted into a format for display on the display panel 131 and is displayed on the display panel 131 as a through image at the time of shooting. Various icon displays stored in advance in the program memory unit 311 can be displayed on the display panel 131.

  FIG. 4a is an exploded perspective view showing a main configuration of the imaging apparatus 1 according to the embodiment of the present invention. From the right side of the drawing, a lens mount 101, a mount holder 147 having an abutting portion 144, a lock portion 104, a mask portion 148, a first polarizing filter 105, an internal gear 142 having a contact portion 145 to be described later, a two-stage spur gear 141, the biasing member 143, the second polarizing filter 106, the electric motor 146, the converter lens 102, and the image sensor 110. The line connecting the lens mount 101 and the center of the image sensor 110 is the optical axis 149. .

  4b is a perspective view of the assembled state of FIG. 4a. FIG. 5 is a perspective view showing a bayonet structure of the interchangeable lens 2 that can be attached to the imaging apparatus 1. The interchangeable lens 2 has a bayonet claw portion 150, a contact portion 151 that is a part of the bayonet claw portion 150, and a concave portion 152 that holds the interchangeable lens 2 by coupling with the lock portion 104.

  4A, 4B and 5, the imaging apparatus 1 includes the first polarizing filter 105 and the second polarizing filter 106 between the lens mount unit 101 and the imaging element 110 and on the optical axis 149. The image pickup apparatus 1 rotates around a light beam 149, a biasing member 143 that biases the two-stage spur gear 141, a two-stage spur gear 141 composed of a large-diameter gear and a small-diameter gear at a location not on the optical axis 149. It has an internal gear 142, an abutting portion 144 that is a mechanical end of the internal gear 142, and a lock portion 104 disposed on the lens mount portion 101.

  The interchangeable lens 2 includes a bayonet claw portion 150, a contact portion 151 that is a part of the bayonet claw portion 150, and a concave portion 152 that holds the interchangeable lens 2 by coupling with the lock portion 104. The internal gear 142 has an abutment portion 145 that abuts against an abutment portion 151 that is a part of the bayonet claw portion 150 when the interchangeable lens 2 is rotationally attached and detached.

  FIG. 6A shows a mechanical connection from a contact portion 145 that is a part of the internal gear 142 that contacts the contact portion 151 to the first polarizing filter 105, and the electric motor 146 and the second polarizing filter 106. It is the figure which showed the mechanical connection. FIG. 6A is a diagram in the case where the interchangeable lens 2 is not attached to the lens mount unit 101. FIG.

  FIG. 6B is a cross-sectional perspective view showing the meshing state of the two-stage spur gear 141 and the internal gear 142 of FIG. 6A for explaining the mechanical connection of FIG. 6A.

  FIG. 7 is a schematic diagram illustrating a state in which the interchangeable lens 2 is attached to the imaging device 1 in FIG. 7 is a view showing that a contact portion 151 which is a part of a bayonet claw portion 150 of the interchangeable lens 2 is in contact with a contact portion 145 which is a part of an internal gear 142. FIG.

  6A, 6B, and 7, the imaging apparatus 1 has a spur gear shape on the outer periphery of the first polarizing filter 105, and the spur gear on the outer periphery of the first polarizing filter 105 is a large diameter spur gear of the two-stage spur gear 141. Engage with gears. Further, the small-diameter spur gear of the two-stage spur gear 141 meshes with the internal gear 142. The two-stage spur gear 141 is urged in the rotational direction by the urging member 143. The internal gear 142 is always urged in the rotational direction 153 for removing the bayonet claw 150 of the interchangeable lens 2. When the interchangeable lens 2 is attached to the lens mount portion 101, the biasing force of the internal gear 142 is a part of the bayonet claw portion 150 via a contact portion 145 that is a part of the internal gear 142. The contact portion 151 is reached. Further, the urging force of the internal gear 142 reaches the recess 152 via the bayonet claw 150 and is received by the lock 104. When the interchangeable lens 2 is not attached, the urging force of the internal gear 142 is received by the contact portion 144.

  When the interchangeable lens 2 is attached to the lens mount unit 101, the polarization directions of the first polarizing filter 105 and the second polarizing filter 106 are substantially parallel. When the interchangeable lens 2 is not attached, the polarization directions of the first polarizing filter 105 and the second polarizing filter 106 are not substantially parallel.

  In the present embodiment, the rotation angle of the first polarizing filter 105 can be made larger than the rotation angle of the internal gear 142 due to the difference in diameter between the small gear and the large gear of the two-stage spur gear 141. is there. Therefore, the rotation angle of the first polarizing filter 105 can be made larger than the rotation angle of the interchangeable lens 2.

  Further, although different from the present embodiment, it is also possible to arrange the second polarizing filter 106 between the converter lens 102 and the image sensor 110, thereby reducing the area of the second polarizing filter 106, Effective for miniaturization.

  With the above configuration, the imaging apparatus 1 arranges the first polarizing filter 105 and the second polarizing filter 106 between the lens mount unit 101 and the imaging element 110 and on the optical axis 149. The first polarizing filter 105 rotates mechanically in conjunction with the attaching / detaching rotation operation of the interchangeable lens 2. Thereby, the imaging apparatus 1 can attenuate light entering the imaging element 110 and can prevent the imaging element 110 from being burnt.

  Therefore, when the imaging apparatus is not energized, such as when an interchangeable lens is detached from the imaging apparatus, an effect of preventing the image sensor from burning can be obtained.

1... Imaging device 1
2 ... Interchangeable lens 2
102 ··· Converter lens 102
110... Image sensor 110
121... REC button 121
122... Rotating dial 122
123... Mode selection dial 123
124 ··· Lens release button 124
131... Display panel 131
132... Panel image processing unit 132
133... Touch panel unit 133
351... Control IC 351
352... Image processing unit 352
104... Lock section 104
105... First polarizing filter 105
106 ··· Second polarizing filter 106
141 ··· Two-stage spur gear 141
142 .... Internal gear 142
143... Biasing member 143
144 ··· Attached part 144
145... Abutment portion 145
146 ... Electric motor 146
147... Mount holder 147
148... Mask portion 148
149 .... Optical axis 149
150 ... Bayonet claw 150
151... Contact portion 151
152 ··· concave portion 152
153 ... Rotation direction 153

Claims (3)

In the imaging apparatus 1 having the bayonet-type interchangeable lens 2 and the lens mount portion 101 corresponding to the bayonet,
A first polarizing filter 105 and a second polarizing filter 106 between the lens mount unit 101 and the image sensor 110 and on the optical axis 149;
A two-stage spur gear 141 composed of a large-diameter gear and a small-diameter gear, a biasing member 143 that biases the two-stage spur gear 141, and an internal gear 142 that rotates around the optical axis 149 are provided on portions that are not on the optical axis 149. And an abutting portion 144 that is a mechanical end of the internal gear 142, and a lock portion 104 disposed on the lens mount portion 101,
The interchangeable lens 2 has a bayonet claw portion 150, a contact portion 151 that is a part of the bayonet claw portion 150, and a concave portion 152 that holds the interchangeable lens 2 by being combined with the lock portion 104,
The internal gear 142 has a contact portion 145 that contacts a contact portion 151 that is a part of the bayonet claw portion 150 when the interchangeable lens 2 is rotationally attached and detached.
The outer periphery of the first polarizing filter 105 has a spur gear shape,
The spur gear on the outer periphery of the first polarizing filter 105 meshes with the large-diameter spur gear of the two-stage spur gear 141,
The small-diameter two-stage spur gear 141 meshes with the internal gear 142,
The two-stage spur gear 141 is urged in the rotational direction of the gear by the urging member 143,
The internal gear 142 always urges the bayonet claw 150 of the interchangeable lens 2 in the rotational direction 153 to remove,
When the interchangeable lens 2 is attached to the lens mount portion 101, the biasing force of the internal gear 142 is one part of the bayonet claw portion 150 via a contact portion 145 that is a part of the internal gear 142. The contact portion 151, which reaches the recess portion 152 through the bayonet claw portion 150, and is received by the lock portion 104,
When the interchangeable lens 2 is not attached, the urging force of the internal gear 142 is received by the abutting portion 144,
When the interchangeable lens 2 is attached to the lens mount unit 101, the polarization directions of the first polarizing filter 105 and the second polarizing filter 106 are parallel,
The imaging apparatus, wherein when the interchangeable lens 2 is not attached, the polarization directions of the first polarizing filter 105 and the second polarizing filter 106 are not parallel. The imaging apparatus according to claim 1, wherein the rotation angle of the first polarizing filter 105 is larger than the rotation angle of the interchangeable lens 2. Like the first polarizing filter 105, the second polarizing filter 106 has a spur gear shape on the outer periphery.
An electric motor 146 having a spur gear at a place not on the optical axis 149;
The imaging device according to claim 1, wherein the second polarizing filter 106 and a spur gear that is a part of the electric motor 146 are engaged with each other.