JP2010186085A - Lens adapter and conversion lens - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens adapter and conversion lens easily and certainly mounted to an imaging device such as a digital still camera or the like. <P>SOLUTION: This lens adapter includes a projection 41 with a shape inserted into a fixed groove 141 formed in an outer peripheral surface of a lens ring 140 of the imaging device, a stopper 40 having the projection 41, a support shaft 23 for rockably supporting the stopper 40, rocking guides 33a and 33b for rocking the stopper 40 so that the projection 41 comes into or out of the fixed groove 141, and an outer frame 30 for operating the rocking guides 33a and 33b so as to form a fixed state where the projection 41 comes into the fixed groove 141 or a released state where the projection 41 comes out of the fixed groove 141. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a lens adapter and a conversion lens that are used by being attached to an imaging apparatus such as a digital still camera.

  2. Description of the Related Art Conventionally, an imaging apparatus such as a digital still camera or a digital video camera forms a subject image with an imaging lens, and is a CCD (Charge Coupled Device Image Sensor) image sensor or CMOS (Complementary Metal Oxide) disposed at the rear of the imaging lens. Semiconductor) A subject image is captured by an image sensor such as an image sensor. For example, in a digital still camera, a retractable zoom lens may be employed in order to capture a subject image at different magnifications and to reduce the thickness.

However, in the retractable zoom lens, the magnification is limited to a narrow range. Therefore, a technique is known in which a tele or wide conversion lens can be mounted via a cylindrical lens adapter that can project a zoom lens into the internal space so that shooting can be performed at a wider magnification. .
Specifically, a cylindrical lens ring that houses the zoom lens unit is protruded from the front surface of the case, and a thread groove is formed on the inner peripheral surface of the lens ring. Further, a thread is formed on the outer peripheral surface on the other end side of the lens adapter to which the conversion lens can be attached on one end side. The lens adapter is screwed into the lens ring so that the conversion lens can be mounted via the lens adapter.

JP 2000-235222 A

However, the technique disclosed in Patent Document 1 has a problem that it takes time to screw the lens adapter, and the mounting is troublesome. In addition, the screw thread is liable to be crushed and there is a problem in durability. Furthermore, when the screwing is insufficient, the lens adapter may drop off, which causes a problem in reliability.
In the case of a single-focus lens, the conversion lens can be directly screwed into the lens ring without using a lens adapter. However, even in this case, it takes time to screw the conversion lens. There is.

  Therefore, the problem to be solved by the present invention is to provide a lens adapter and a conversion lens that can be easily and reliably attached to an imaging apparatus such as a digital still camera.

The present invention solves the above-described problems by the following means.
According to a first aspect of the present invention, a protrusion having a shape that fits into a groove formed on an outer peripheral surface of a lens ring of an imaging device, a fixed piece having the protrusion, and a swinging of the fixed piece. A support shaft that is movably supported; a swing guide for swinging the fixed piece so that the protrusion enters and exits the groove; and a fixed state in which the protrusion enters the groove or the protrusion A lens adapter having an operation unit that operates the swing guide so as to be in a released state that has come out of the groove, and a mounting unit on which an optical component can be mounted so as to coincide with the optical axis of the imaging lens of the imaging device; is there.

  According to a sixth aspect of the present invention, a projection having a shape that fits into a groove formed on an outer peripheral surface of a lens ring of an imaging device, a fixing piece having the protrusion, and the fixing piece A swinging support for swinging the fixed piece so that the protrusion enters and exits the groove, and a fixed state in which the protrusion enters the groove or the protrusion. It is a conversion lens having an operation unit that operates the swing guide so that the unit is released from the groove, and an auxiliary lens for changing the focal length of the imaging lens of the imaging device.

(Function)
The inventions according to the first and sixth aspects have protrusions shaped to fit into grooves formed on the outer peripheral surface of the lens ring of the image pickup apparatus. In addition, an operation unit is provided that causes the protrusion to enter a fixed state where the protrusion enters the groove or a release state where the protrusion protrudes from the groove. For this reason, in order to attach the lens adapter or the conversion lens to the imaging apparatus, the operation unit may be in a fixed state in which the protrusion enters the groove.
On the other hand, in order to remove from the imaging device, it is only necessary to bring the protruding portion out of the groove.

  According to the present invention, the lens adapter and the conversion lens can be easily attached to the imaging apparatus because the projection can be attached to and detached from the groove simply by moving the projection into and out of the groove. In addition, since the projecting portion enters the groove, it is in a fixed state, so that the lens adapter and the conversion lens are securely attached.

It is a perspective view which shows the front side of the digital still camera which can mount | wear with the lens adapter of this invention. It is a perspective view which shows the back side of the digital still camera which can mount | wear with the lens adapter of this invention. It is a block diagram which shows the structure of the digital still camera which can mount | wear with the lens adapter of this invention. It is a perspective view which shows the condition at the time of attaching a lens adapter as one Embodiment (1st Embodiment) of the lens adapter of this invention. It is a perspective view showing a lens adapter as one embodiment (first embodiment) of a lens adapter of the present invention. It is a perspective view which shows the inner frame of a lens adapter as one Embodiment (1st Embodiment) of the lens adapter of this invention. It is a perspective view which shows the cancellation | release state of a lens adapter as one Embodiment (1st Embodiment) of the lens adapter of this invention. It is sectional drawing which shows the cancellation | release state of a lens adapter as one Embodiment (1st Embodiment) of the lens adapter of this invention. It is a perspective view which shows the fixed state of the lens adapter as one Embodiment (1st Embodiment) of the lens adapter of this invention. It is sectional drawing which shows the fixed state of the lens adapter as one Embodiment (1st Embodiment) of the lens adapter of this invention. It is sectional drawing which shows the cancellation | release state of a lens adapter as one Embodiment (2nd Embodiment) of the lens adapter of this invention. It is a perspective view which shows the cancellation | release state of a lens adapter as one Embodiment (3rd Embodiment) of the lens adapter of this invention. It is a perspective view which shows the fixed state of the lens adapter as one Embodiment (3rd Embodiment) of the lens adapter of this invention. It is sectional drawing which shows the cancellation | release state of a lens adapter as one Embodiment (4th Embodiment) of the lens adapter of this invention. It is sectional drawing which shows the fixed state of the lens adapter as one Embodiment (4th Embodiment) of the lens adapter of this invention. It is sectional drawing which shows the fixed state of the teleconversion lens as one Embodiment (5th Embodiment) of the conversion lens of this invention.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
Here, the imaging apparatus according to the present invention is assumed to be a digital still camera 100 in the following embodiments. In addition, the lens adapter in the present invention is assumed to be the lens adapters 10, 50 to 70 that are used by being mounted on the digital still camera 100. Furthermore, it is assumed that the conversion lens in the present invention is a teleconversion lens 80 used by being mounted on a digital still camera.
The description will be given in the following order:

1. 1st Embodiment (The operation part: The example fixed by the movement to an optical axis direction and a circumferential direction)
2. Second Embodiment (Fixed piece: Example using elastic material for protrusion)
3. Third embodiment (operation unit: an example of fixing only by movement in the optical axis direction)
4). Fourth embodiment (operation unit: an example of fixing only by movement in the circumferential direction)
5). Fifth embodiment (example in which a teleconversion lens is directly fixed)

[Configuration example of imaging device]

FIG. 1 is a perspective view showing the front side of a digital still camera 100 to which the lens adapters 10, 50 to 70 of the present invention can be attached.
FIG. 2 is a perspective view showing the back side of the digital still camera 100 to which the lens adapters 10, 50 to 70 of the present invention can be attached.
As shown in FIGS. 1 and 2, the digital still camera 100 has a rectangular parallelepiped case 110 constituting an exterior. A zoom lens unit 130 and a lens ring 140 that protrudes from the periphery of the zoom lens unit 130 and has a fixed groove 141 (corresponding to a groove in the present invention) formed on the outer peripheral surface are provided on the front surface of the case 110.

Above the zoom lens unit 130, a flash 111 for emitting photographing auxiliary light, an AF (Auto Focus) auxiliary light emitting unit 112, and a finder window 113 are provided in order from the left. On the upper surface of the case 110, a power button 114 for turning on / off the power and a shutter button 115 for photographing are arranged.
Note that “up / down / left / right” means up / down / left / right of the digital still camera 100 as viewed in FIG.

Furthermore, as shown in FIG. 2, a display 116, a zoom lever 117, a menu button 118, a cross key 119, a determination button 120, and an exposure correction button 121 are provided on the rear surface of the case 110.
The display 116 is a liquid crystal display or the like, and displays a photographed image, reproduces a photographed image, etc. in addition to a setting menu. The zoom lever 117 is operated when the operator performs zooming (magnification operation). The menu button 118 is operated when various setting menus (still image shooting mode, moving image shooting mode, playback mode, etc.) are displayed on the display 116. The displayed setting menu is selected with the cross key 119 and pressed. Determine at 120. The exposure correction button 121 is operated when performing exposure correction such as backlight correction with one touch by opening and closing the aperture.

In such a digital still camera 100, the zoom lens unit 130 (see FIG. 1) is a retractable type. For this reason, when the power is turned off, it is housed inside the case 110, thereby improving portability when not in use and preventing the zoom lens unit 130 from being damaged.
On the other hand, when the power is turned on, it protrudes from the front surface of the case 110 and photography is possible. Then, the subject image formed by the front lens 131 (one of the imaging lenses) or the like is photographed by the imaging element 122 disposed at the rear part of the zoom lens unit 130.
As the image sensor 122, for example, a CCD (Charge Coupled Device) image sensor, a CMOS (Complementary Metal Oxide Semiconductor) image sensor, or the like can be used.

  In addition, the zoom lens unit 130 is disposed inside the fixed barrel 132 disposed inside the lens ring 140, the outer movable barrel 133 disposed inside the fixed barrel 132, and the outer movable barrel 133. The inner movable lens barrel 134 is provided. When the power is turned on, the outer movable barrel 133 projects from the fixed barrel 132 and the inner movable barrel 134 projects from the outer movable barrel 133.

Here, the fixed barrel 132 is disposed inside the case 110, and the front surface protrudes at substantially the same height as the lens ring 140. A focus lens 135 (not shown) and a diaphragm 136 (not shown) are provided inside the fixed barrel 132. The outer movable barrel 133 is formed with an outer diameter substantially the same as the inner diameter of the fixed barrel 132 and is supported so as to be able to advance and retreat forward from the fixed barrel 132. Inside the zoom lens 137 is provided. (Not shown) is provided. Furthermore, the inner movable lens barrel 134 is formed with an outer diameter substantially the same as the inner diameter of the outer movable lens barrel 133 and is supported so as to be able to move forward and backward from the outer movable lens barrel 133. A zoom lens 138 (not shown) is provided.
The focus lens 135, the zoom lens 137, and the zoom lens 138 together with the front lens 131 constitute an imaging lens of the digital still camera 100.

Further, an openable / closable lens cover 139 is provided at the tip of the inner movable barrel 134. When the power of the digital still camera 100 is turned on and the zoom lens unit 130 (the outer movable lens barrel 133 and the inner movable lens barrel 134) protrudes, the lens cover 139 is opened and the front lens 131 is exposed to allow photographing. It becomes.
On the other hand, when the power is turned off and the outer movable lens barrel 133 and the inner movable lens barrel 134 are accommodated in the fixed lens barrel 132, the lens cover 139 is closed to protect the front lens 131.

FIG. 3 is a block diagram showing the configuration of the digital still camera 100 to which the lens adapters 10, 50 to 70 of the present invention can be attached.
As shown in FIG. 3, the digital still camera 100 includes a zoom lens unit 130, and a front lens 131, a zoom lens 138, a zoom lens 137, and a focus lens 135 are arranged along the optical axis.

  An aperture 136 is disposed between the zoom lens 137 and the focus lens 135. The diaphragm 136 is driven by the diaphragm driving device 123 and can increase or decrease the opening amount. For example, when shooting a bright subject, in order to reduce the amount of light incident on the image sensor 122 disposed at the rear of the focus lens 135, the amount of light of the aperture 136 is reduced to reduce the amount of light. Conversely, when shooting a dark subject, in order to increase the amount of light incident on the image sensor 122, the amount of aperture of the diaphragm 136 is increased to increase the amount of light.

Furthermore, the focus lens 135 is movable in the optical axis direction and is driven by the focus lens driving device 124. The focus lens driving device 124 is, for example, a stepping motor or a linear motor, and performs focusing (focus adjustment operation) by sliding the focus lens 135 in the optical axis direction.
Furthermore, the outer movable barrel 133 (see FIG. 1) including the zoom lens 137 and the inner movable barrel 134 (see FIG. 1) including the zoom lens 138 can be moved in the optical axis direction by a stepping motor, a linear motor, or the like. And is driven by the zoom lens driving device 125.

The digital still camera 100 includes an A / D (Analog / Digital) conversion unit 126, a camera DSP (Digital Signal Processor) 127, a memory 128, a display 116, a zoom lever 117, and a CPU (Central Processing Unit) 129. Is provided.
Among these, the A / D converter 126 converts the analog signal output from the image sensor 122 into a digital signal. Specifically, the subject image formed by the zoom lens unit 130 is photoelectrically converted by the image sensor 122, and an analog signal as an output thereof is converted into a digital signal by the A / D converter 126.

  The converted digital signal is subjected to processing such as gamma correction, color separation, and color difference matrix by the camera DSP 127. Then, it is stored in the memory 128 and displayed on the display 116 as a subject image. Further, the luminance data of the digital signal converted by the A / D conversion unit 126 is transmitted to the CPU 129.

  The CPU 129 performs calculation for exposure control based on the transmitted luminance data. If the result is not appropriate, the aperture driving device 123 is controlled to adjust the aperture 136 so that the exposure becomes appropriate. In addition, the CPU 129 controls the focus lens driving device 124 and slides the focus lens 135 to perform focusing (focus adjustment operation). Furthermore, the CPU 129 controls the zoom lens driving device 125 according to the operation of the zoom lever 117, and performs zooming (magnification operation) by sliding the zoom lens 137 and the zoom lens 138.

As described above, the digital still camera 100 performs auto exposure control and auto focus control by the CPU 129. Further, the zoom lens unit 130 is zoomed by operating the zoom lever 117, and photographing at different magnifications becomes possible. Furthermore, when photographing at a wider magnification, the lens adapters 10 and 50 to 70 (not shown: corresponding to optical auxiliary parts) are attached to the lens ring 140 (see FIG. 1). Then, a tele or wide conversion lens is attached to the lens adapter 10, 50-70.
In the case of a single-focus lens digital still camera, a teleconversion lens 80 (not shown: corresponding to an optical component) is directly attached.

<1. First Embodiment>
[Example of lens adapter configuration]

FIG. 4 is a perspective view showing a situation when the lens adapter 10 is attached as one embodiment (first embodiment) of the lens adapter of the present invention.
As shown in FIG. 4, the digital still camera 100 includes a retractable zoom lens unit 130. Here, when using the teleconversion lens 150 that enables photographing at a higher magnification, if the heavy teleconversion lens 150 is directly attached to the zoom lens unit 130, a load is applied to the drive system of the zoom lens unit 130, resulting in failure. Cause.

Therefore, the cylindrical lens adapter 10 is attached to the lens ring 140 of the digital still camera 100, and the teleconversion lens 150 is attached to the lens adapter 10. The lens adapter 10 includes an inner frame 20 and an outer frame 30. Then, after the extrapolated portion 21 of the inner frame 20 is extrapolated to the lens ring 140, it is fixed to the fixing groove 141. The teleconversion lens 150 is mounted by screwing into the mounting portion 22 of the inner frame 20.
In actual use, the teleconversion lens 150 and the wide conversion lens are screwed into the mounting portion 22 of the lens adapter 10 in advance, and the lens adapter 10 is attached to the lens ring 140 with one touch.

  Thus, the teleconversion lens 150 is attached to the digital still camera 100 via the cylindrical lens adapter 10. Therefore, the internal space of the lens adapter 10 becomes a protruding region of the zoom lens unit 130. Therefore, the zoom lens unit 130 is not burdened with the weight of the teleconversion lens 150, and zooming of the zoom lens unit 130 is not hindered.

FIG. 5 is a perspective view showing a lens adapter 10 as one embodiment (first embodiment) of the lens adapter of the present invention.
FIG. 6 is a perspective view showing an inner frame 20 of the lens adapter 10 as one embodiment (first embodiment) of the lens adapter of the present invention.
As shown in FIG. 5, the lens adapter 10 according to the first embodiment has an inner frame 20, an outer frame 30 (corresponding to an operation unit in the present invention), and a stopper 40 (corresponding to a fixed piece in the present invention). is doing.

Here, the inner frame 20 has an extrapolation portion 21 that can be extrapolated to the outer peripheral surface of the lens ring 140 (see FIG. 4), and a teleconversion lens so as to coincide with the optical axis of the zoom lens unit 130 (see FIG. 4). 150 (see FIG. 4). Therefore, if the extrapolation part 21 is extrapolated to the lens ring 140 and the teleconversion lens 150 is attached to the attachment part 22, it is possible to shoot at a higher magnification than when only the zoom lens unit 130 is used.
Note that a thread groove is formed on the inner peripheral surface of the mounting portion 22 so that various optical components such as the teleconversion lens 150 and the wide conversion lens can be screwed in and mounted.

The inner frame 20 has a support shaft 23 (see FIG. 5) that supports the stopper 40 in a swingable manner. Three support shafts 23 are formed at positions that divide the circumference of the extrapolated portion 21 into three equal parts, and stoppers 40 are fitted in the respective support shafts 23. Therefore, the three stoppers 40 can be rotated by movement like a seesaw around each support shaft 23. As shown in FIG. 6, each stopper 40 is formed with a protrusion 41, a peak 42, and a valley 43, and the protrusion 41 is a fixing groove 141 (see FIG. 4) of the lens ring 140 (see FIG. 4). (See FIG. 4).
The support shaft 23 and the stopper 40 are not limited to three, and may be four or more.

Furthermore, the inner frame 20 has a guide groove 24. Three guide grooves 24 are formed in the same manner as the support shaft 23 (see FIG. 5), and guides the outer frame 30 (see FIG. 5) externally inserted into the inner frame 20.
Specifically, each guide groove 24 is substantially L from the release position 24a on the mounting portion 22 side toward the outer insertion portion 21, and then reaching the fixed position 24b in the circumferential direction of the outer insertion portion 21. It has a letter shape. Each guide groove 24 is fitted with a guide protrusion 31 (not shown) formed on the inner peripheral surface of the outer frame 30. Therefore, the outer frame 30 can move along the guide grooves 24 in the optical axis direction of the zoom lens unit 130 (see FIG. 4), and the outer frame 30 faces the digital still camera 100 (see FIG. 1). The zoom lens unit 130 can be rotated in the circumferential direction in the moved state.

  Further, the inner frame 20 has a holding portion 25 for holding the outer frame 30 moved along the guide grooves 24 at the fixed position 24b. In the holding portion 25, when the guide projection 31 (not shown) of the outer frame 30 reaches the fixed position 24b, the holding projection 32 (not shown) formed on the outer frame 30 has a suitable click feeling. It is provided to be fitted. Therefore, in the outer frame 30, the holding projection 32 is held by the holding portion 25 with an appropriate force in a state where the guide projection 31 is moved to the fixing position 24b.

On the other hand, the outer frame 30 (see FIG. 5) has a swing guide 33 (see FIG. 5) on the inner peripheral surface. According to the positional relationship between the swing guide 33 and the stopper 40, the protrusion 40 shown in FIG. 6 is moved into and out of the fixing groove 141 (see FIG. 4) of the lens ring 140 (see FIG. 4). Rock.
Specifically, when the guide protrusion 31 (not shown) of the outer frame 30 is at the release position 24 a, the stopper 40 can be removed by the positional relationship between the crest 42 and trough 43 of the stopper 40 and the swing guide 33. Open in the direction. Therefore, the projecting portion 41 is released from the fixing groove 141. Conversely, when the guide protrusion 31 is at the fixed position 24b (see FIG. 6), the stopper 40 swings so as to close inward, and the protruding portion 41 enters the fixed groove 141.
In addition, on the side surface of the outer frame 30, for the convenience when the outer frame 30 is moved and the swing guide 33 is operated, a holding portion 34 with a depression is formed. In addition, on the lower surface of the outer frame 30, a platform mounting portion 35 that has been D-cut processed in consideration of attachment of a tripod platform 160 (not shown) is formed.

FIG. 7 is a perspective view showing a released state of the lens adapter 10 as one embodiment (first embodiment) of the lens adapter of the present invention.
FIG. 8 is a cross-sectional view showing a released state of the lens adapter 10 as one embodiment (first embodiment) of the lens adapter of the present invention.
As shown in FIGS. 7 and 8, when the outer frame 30 is positioned on the mounting portion 22 side of the inner frame 20, the stopper 40 is released.

In this release state, the guide protrusion 31 of the outer frame 30 is in the release position 24a (see FIG. 7) of the guide groove 24 of the inner frame 20. As a result, the swing guide 33a of the outer frame 30 comes into contact with the upper surface of the peak portion 42 of the stopper 40 and pushes the peak portion 42 down.
On the other hand, the swing guide 33 b is located above the valley portion 43 of the stopper 40, and there is a gap between the stopper 40. Therefore, the stopper 40 rotates counterclockwise around the support shaft 23 (see FIG. 8) so that the peak portion 42 is pushed down, and the protrusion 41 on the opposite side of the peak portion 42 opens outward. become.

  Therefore, when the outer frame 30 is positioned on the mounting portion 22 side of the inner frame 20 and the guide protrusion 31 is set to the release position 24a (see FIG. 7) of the guide groove 24, the swing guide 33a causes the peak portion 42 of the stopper 40 to move. The protrusion 41 is opened by pushing down. Therefore, as shown in FIG. 8, the protrusion 41 is in a state in which it protrudes from the fixing groove 141 of the lens ring 140 inserted in the outer insertion portion 21. As a result, the lens ring 140 is released from the extrapolation portion 21 of the lens adapter 10 in a released state.

FIG. 9 is a perspective view showing a fixed state of the lens adapter 10 as one embodiment (first embodiment) of the lens adapter of the present invention.
FIG. 10 is a cross-sectional view showing a fixed state of the lens adapter 10 as one embodiment (first embodiment) of the lens adapter of the present invention.
As shown in FIGS. 9 and 10, if the outer frame 30 is positioned on the outer insertion portion 21 side of the inner frame 20, the stopper 40 is in a fixed state.

In this fixed state, the guide protrusion 31 of the outer frame 30 is in the fixing position 24b (see FIG. 9) of the guide groove 24 of the inner frame 20. As a result, the swing guide 33b of the outer frame 30 comes into contact with the upper surface of the protrusion 41 of the stopper 40 and pushes down the protrusion 41.
On the other hand, the swing guide 33a is located above the support shaft 23 (see FIG. 10) and is not only separated from the mountain portion 42 but also affects the swing of the stopper 40 around the support shaft 23. It is in a position that does not reach. Therefore, the stopper 40 rotates clockwise around the support shaft 23 so that the protrusion 41 is pushed down, and the protrusion 41 closes inward.

  Therefore, if the outer frame 30 is positioned on the outer insertion portion 21 side of the inner frame 20 and the guide protrusion 31 is set to the fixing position 24b (see FIG. 9) of the guide groove 24, the swing guide 33b is the protrusion 41 of the stopper 40. Is pushed down to swing the projection 41 in the closing direction. Therefore, as shown in FIG. 10, the protrusion 41 enters the fixing groove 141 of the lens ring 140 inserted into the outer insertion portion 21. As a result, the lens ring 140 is fixed to the extrapolation portion 21 of the lens adapter 10.

  Further, as shown in FIG. 9, the holding projection 32 of the outer frame 30 is held by the holding portion 25 with an appropriate force. Therefore, it is prevented that the outer frame 30 moves naturally and the fixed state is inadvertently released. Furthermore, the lens adapter 10 can cope with zooming of the zoom lens unit 130 by the internal space of the inner frame 20 as shown in FIG. Furthermore, the large platform 160 can be accommodated by the platform mounting part 35 of the outer frame 30.

As described above, in the lens adapter 10 according to the first embodiment, the protrusion 41 enters the fixing groove 141 from the released state (see FIG. 8) in which the protrusion 41 of the stopper 40 has come out of the fixing groove 141 of the lens ring 140. It is possible to easily shift to the fixed state (see FIG. 10).
Specifically, in the released state shown in FIGS. 7 and 8, the extrapolated portion 21 of the inner frame 20 is extrapolated to the lens ring 140 as shown in FIG. 8.

Next, it operates so that the outer frame 30 may be moved to the optical axis direction which goes to the extrapolation part 21. FIG. As a result, the guide protrusion 31 of the outer frame 30 moves away from the release position 24a (see FIG. 7) and moves straight along the guide groove 24 of the inner frame 20.
Further, the swing guide 33a of the outer frame 30 moves away from the peak portion 42 of the stopper 40, and the swing guide 33b of the outer frame 30 comes into contact with the upper surface of the protrusion 41 of the stopper 40. As a result, the stopper 40 rotates clockwise about the support shaft 23, and the protrusion 41 of the stopper 40 fits into the fixing groove 141 of the lens ring 140 as shown in FIG.

Therefore, in the lens adapter 10 of the first embodiment, the outer frame 30 is operated and moved toward the outer insertion portion 21 of the inner frame 20, so that the protrusion 41 enters the fixing groove 141. Become.
The swing guide 33a and the swing guide 33b are formed in advance so as to be in a fixed state when the outer frame 30 is moved toward the outer insertion portion 21, and the protrusion 41 is formed in the fixing groove 141. It is pre-formed in a shape that fits.

Here, since the outer frame 30 is movable in the optical axis direction, the outer frame 30 may move back toward the mounting portion 22 after being moved toward the outer insertion portion 21. And the protrusion 41 may be in the release state where it has slipped out of the fixed groove 141.
Therefore, after the outer frame 30 is moved toward the outer insertion portion 21, the outer frame 30 is further rotated clockwise in the circumferential direction. As a result, as shown in FIG. 9, the guide protrusion 31 of the outer frame 30 moves to the fixing position 24 b, and the holding protrusion 32 of the outer frame 30 is held by the holding portion 25 of the inner frame 20. Therefore, it is possible to prevent inadvertent return to the release state.

Conversely, in order to change the lens adapter 10 of the first embodiment from the fixed state (see FIG. 10) to the released state (see FIG. 8), in the fixed state shown in FIG. Rotate counterclockwise. As a result, the holding protrusion 32 of the outer frame 30 is detached from the holding portion 25 of the inner frame 20.
Further, the outer frame 30 is moved toward the mounting portion 22, and the guide protrusion 31 is positioned at the release position 24a as shown in FIG. As a result, the swing guide 33a of the outer frame 30 pushes down the peak portion 42 of the stopper 40, and the protruding portion 41 as shown in FIG. 8 is released from the fixed groove 141.

  Therefore, the lens adapter 10 according to the first embodiment can be fixed to the lens ring 140 easily and reliably by one-touch two-action (moving and rotating the outer frame 30) as in the bayonet method. In addition, it is not necessary to provide an unpleasant key groove as in the bayonet method, and it is not necessary to hide the key groove using another member.

Compared to the case where a flexible claw integrally formed on the inner frame is used instead of the stopper 40 supported in a swingable manner on the support shaft 23, the claw may be scraped during attachment or detachment. The load does not act.
In addition, it is also conceivable to use a claw that is warped outward in advance so as not to contact the lens ring 140. However, if it is fixed for a long time in a high temperature environment, the necessary warpage shape is deformed by thermal creep, and the warpage is reduced. For this reason, the flexible claw eventually causes problems such as shaving and load on the lens ring 140.

<2. Second Embodiment>
[Example of lens adapter configuration]

FIG. 11 is a cross-sectional view showing a released state of the lens adapter 50 as one embodiment (second embodiment) of the lens adapter of the present invention.
As shown in FIG. 11, the lens adapter 50 of the second embodiment includes the inner frame 20, the outer frame 30, and the stopper 40 in the same manner as the lens adapter 10 (see FIG. 8) of the first embodiment. Have.

Here, the inner frame 20 supports the outer insertion portion 21 that can be extrapolated to the outer peripheral surface of the lens ring 140, the mounting portion 22 that can mount an optical component such as a conversion lens, and the stopper 40 so as to swing freely. And a shaft 23. The stopper 40 formed with the elastic protrusion 51, the peak portion 42, and the valley portion 43 can be rotated by a movement like a seesaw around the support shaft 23, and the elastic protrusion 51 is fixed to the fixing groove of the lens ring 140. Enter and exit 141.
In addition, although the support shaft 23 and the stopper 40 are provided in the position which divides the circumference of the extrapolation part 21 into 3 equally, four or more may be sufficient.

The inner frame 20 has a guide groove 24. The guide groove 24 guides the guide protrusion 31 of the outer frame 30 that is extrapolated to the inner frame 20. Therefore, the outer frame 30 can move in the optical axis direction along the guide groove 24.
The guide groove 24 has a substantially L shape similar to the lens adapter 10 (see FIG. 7) of the first embodiment. Therefore, after the outer frame 30 is moved toward the outer insertion portion 21, the outer frame 30 can be further rotated clockwise in the circumferential direction.

  Furthermore, the outer frame 30 has a swing guide 33a and a swing guide 33b. The swing guide 33 a and the swing guide 33 b swing the stopper 40 so that the elastic protrusion 51 enters and exits the fixing groove 141 of the lens ring 140 according to the positional relationship with the stopper 40. Further, on the lower surface of the outer frame 30, a platform mounting portion 35 that has been D-cut processed in consideration of attachment of a tripod platform 160 (see FIG. 10) is formed.

In the lens adapter 50 according to the second embodiment, the elastic protrusion 51 is fixed to the fixing groove 141 from the released state (see FIG. 11) in which the elastic protrusion 51 of the stopper 40 has come out of the fixing groove 141 of the lens ring 140. It can be easily shifted to the fixed state.
Specifically, first, the extrapolated portion 21 of the inner frame 20 is extrapolated to the lens ring 140 in the release state shown in FIG.

Next, it operates so that the outer frame 30 may be moved to the optical axis direction which goes to the extrapolation part 21. FIG. As a result, the guide protrusion 31 of the outer frame 30 moves straight along the guide groove 24 of the inner frame 20.
Further, the swing guide 33 a of the outer frame 30 is separated from the peak portion 42 of the stopper 40, and the swing guide 33 b of the outer frame 30 comes into contact with the upper surface of the elastic protrusion 51 of the stopper 40. As a result, the stopper 40 rotates clockwise about the support shaft 23, and the elastic protrusion 51 fits into the fixing groove 141 of the lens ring 140.

Therefore, the lens adapter 50 according to the second embodiment is in a fixed state in which the elastic protrusion 51 enters the fixing groove 141 by operating the outer frame 30 and moving it toward the outer insertion portion 21 of the inner frame 20. It becomes.
In addition, after moving the outer frame 30 toward the extrapolation part 21, the outer frame 30 is further rotated clockwise in the circumferential direction, whereby the lens adapter 10 of the first embodiment (see FIG. 9). Similarly, the holding projection of the outer frame 30 is held by the holding portion of the inner frame 20. Therefore, it is possible to prevent inadvertent return to the release state.

  Here, the elastic protrusion 51 is formed of a material having elasticity (in this embodiment, rubber), and the resin peak portion 42 and valley portion 43 and the rubber elastic protrusion 51 are two-color molded. Etc. are integrally formed. Therefore, in the stopper 40, the elastic protrusion 51 entering and exiting the fixed groove 141 has appropriate elasticity. Thereby, when the elastic protrusion 51 is fitted in the fixing groove 141, the elastic protrusion 51 is slightly crushed, so that the lens adapter 50 is firmly fixed and the play when attached is completely prevented.

Further, it is possible to prevent powder blowing due to rubbing between the stopper 40 and the lens ring 140 when the lens adapter 50 is attached, and durability is improved. Furthermore, the contact noise when the lens adapter 50 is attached / detached can be reduced, and the convenience for the user is improved.
If the groove is wide and deep, the area where the elastic protrusion is fitted can be increased, so that more reliable fixation is possible.

<3. Third Embodiment>
[Example of lens adapter configuration]

FIG. 12 is a perspective view showing a released state of the lens adapter 60 as one embodiment (third embodiment) of the lens adapter of the present invention.
FIG. 13 is a perspective view showing a fixed state of the lens adapter 60 as one embodiment (third embodiment) of the lens adapter of the present invention.
As shown in FIGS. 12 and 13, the lens adapter 60 of the third embodiment is similar to the lens adapter 10 of the first embodiment (see FIGS. 7 and 9). 30 and a stopper 40. The stopper 40 is swingably supported on the support shaft of the inner frame 20.

Here, the inner frame 20 has a guide groove 61. Three guide grooves 61 are provided at positions that divide the circumference of the mounting portion 22 into three equal parts, and guide the outer frame 30 that is extrapolated to the inner frame 20.
Specifically, each guide groove 61 is linear from the release position 61a on the mounting portion 22 side toward the outer insertion portion 21 until reaching the fixed position 61b. Each guide groove 61 is fitted with a guide protrusion 62 formed on the inner peripheral surface of the outer frame 30. Therefore, the outer frame 30 can move along the guide grooves 61 in the optical axis direction of the zoom lens unit 130 (see FIG. 4).

  Further, the inner frame 20 has a holding portion 63 for holding the outer frame 30 moved along the respective guide grooves 61 at a fixed position 61b. The holding portion 63 is provided such that when the guide protrusion 62 of the outer frame 30 reaches the fixed position 61b, the holding protrusion 64 formed on the outer frame 30 is fitted with an appropriate click feeling. Therefore, in the outer frame 30, the holding protrusion 64 is held by the holding portion 63 with an appropriate force in a state where the guide protrusion 62 has moved to the fixing position 61b.

Furthermore, the outer frame 30 has a swing guide 33a and a swing guide 33b on the inner peripheral surface. The swing guide 33a and the swing guide 33b are arranged so that the protrusion 41 enters and exits the fixing groove 141 (see FIG. 4) of the lens ring 140 (see FIG. 4) according to the positional relationship with the stopper 40. 40 is swung.
Specifically, as shown in FIG. 12, when the outer frame 30 is positioned on the mounting portion 22 side of the inner frame 20 and the guide protrusion 62 is at the release position 61 a of the guide groove 61, the swing guide 33 a is the stopper 40. The peak portion 42 is pushed down to swing the projection 41 in the opening direction. Therefore, the protrusion 41 is in a state of coming out of the fixing groove 141 of the lens ring 140 inserted in the outer insertion portion 21. As a result, the lens ring 140 is released from the extrapolation portion 21 of the lens adapter 10 in a released state.

On the other hand, as shown in FIG. 13, when the outer frame 30 is moved to the outer insertion portion 21 side of the inner frame 20 so that the guide protrusion 62 is positioned at the fixed position 61b of the guide groove 61, the swing guide 33b is stopped. The protrusion 41 of 40 is pushed down and rocked in the direction of closing the protrusion 41. Therefore, the protrusion 41 enters the fixing groove 141 (see FIG. 4) of the lens ring 140 (see FIG. 4) inserted in the extrapolation portion 21. As a result, the lens ring 140 is fixed to the extrapolation portion 21 of the lens adapter 10.
Further, the holding protrusion 64 of the outer frame 30 is held by the holding portion 63 with an appropriate force. Therefore, it is possible to prevent the outer frame 30 from moving naturally and inadvertently releasing the fixed state.

As described above, the lens adapter 60 according to the third embodiment can be easily and reliably fixed to the lens ring 140 (see FIG. 4) by one-touch / one-action only for the movement operation of the outer frame 30. Therefore, the convenience is further improved as compared with the lens adapter 10 (see FIGS. 7 and 9) of the first embodiment.
In the lens adapter 60 of the third embodiment, since the outer frame 30 only moves linearly, the holding force of the holding protrusion 64 by the holding portion 63 is increased in order to avoid inadvertent release of the fixed state. It is preferable to set. For example, the holding force 63 may be adjusted by deepening the dent of the holding portion 63 and increasing the holding protrusion 64 according to the dent.

<4. Fourth Embodiment>
[Example of lens adapter configuration]

FIG. 14 is a cross-sectional view showing a released state of the lens adapter 70 as one embodiment (fourth embodiment) of the lens adapter of the present invention.
FIG. 15 is a cross-sectional view showing a fixed state of the lens adapter 70 as one embodiment (fourth embodiment) of the lens adapter of the present invention.
As shown in FIGS. 14 and 15, the lens adapter 70 of the fourth embodiment is similar to the lens adapter 10 of the first embodiment (see FIGS. 8 and 10). 30 and a stopper 40.

Here, the inner frame 20 supports the outer insertion portion 21 that can be extrapolated to the outer peripheral surface of the lens ring 140, the mounting portion 22 that can mount an optical component such as a conversion lens, and the stopper 40 so as to swing freely. And a shaft 23. The stopper 40 on which the protrusion 41 is formed can be rotated by a movement like a seesaw about the support shaft 23, and the protrusion 41 enters and exits the fixing groove 141 of the lens ring 140.
In addition, although the support shaft 23 and the stopper 40 are provided in the position which divides the circumference of the extrapolation part 21 into 3 equally, four or more may be sufficient.

Further, the inner frame 20 has a leaf spring 71 that urges one end of the stopper 40 to be pushed down. Therefore, the stopper 40 rotates counterclockwise around the support shaft 23 so that the leaf spring 71 side is pushed down, and the protrusion 41 on the opposite side to the leaf spring 71 is urged so that it always opens outward. It is in the state.
Furthermore, the inner frame 20 has a guide groove 72. The guide groove 72 is formed with a predetermined length in the circumferential direction of the inner frame 20, and guides the guide protrusion 73 of the outer frame 30 that is extrapolated to the inner frame 20. Therefore, the outer frame 30 can rotate within a predetermined range in the circumferential direction along the guide groove 72.

Further, the outer frame 30 has a swing guide 74. The swing guide 74 is formed on an inclined surface such that one end side is low and the other end side is high. Specifically, from the shape having almost no height as shown in FIG. 14, the outer frame 30 is rotated clockwise in the circumferential direction until it becomes a shape having a height as shown in FIG. 15. To change. And finally, it becomes a certain height. Furthermore, on the lower surface of the outer frame 30, there is formed a platform mounting portion 35 that has been subjected to D-cut processing in consideration of attachment of a tripod platform 160 (see FIG. 10).
Note that the swing guide 74 having a lower end and a higher end can also be applied to the lens adapter 10 (see FIGS. 8 and 10) of the first embodiment.

In the lens adapter 70 according to the fourth embodiment, the protrusion 41 enters the fixing groove 141 from the released state (see FIG. 14) in which the protrusion 41 of the stopper 40 has come out of the fixing groove 141 of the lens ring 140. It is possible to easily shift to the fixed state (see FIG. 15).
Specifically, first, the extrapolated portion 21 of the inner frame 20 is extrapolated to the lens ring 140 in the release state shown in FIG.

Next, the outer frame 30 is operated to rotate clockwise in the circumferential direction. As a result, the guide projection 73 of the outer frame 30 rotates clockwise along the guide groove 72 of the inner frame 20.
Further, the swing guide 74 of the outer frame 30 is gradually increased, and the upper surface of the protrusion 41 is pushed down. As a result, the stopper 40 turns clockwise about the support shaft 23 against the bias of the leaf spring 71, and the protrusion 41 is fixed to the fixing groove of the lens ring 140 as shown in FIG. Get stuck in 141.

  Therefore, the lens adapter 70 of the fourth embodiment is in a fixed state in which the protrusion 41 enters the fixing groove 141 by operating the outer frame 30 and rotating it clockwise in the circumferential direction. Therefore, it can be fixed easily and reliably by one-touch and one-action (only the rotation operation of the outer frame 30), so that it is more convenient than the lens adapter 10 of the first embodiment (see FIGS. 8 and 10). Will improve.

Further, since the swing guide 74 is formed so as to gradually increase in the clockwise rotation direction, the protrusion 41 is pressed more strongly in the fixed state shown in FIG. Therefore, rattling of the fixed lens adapter 70 is completely prevented. In addition, since the depth of the fixing groove 141 can be minimized while maintaining the attachment strength that can sufficiently withstand the stress at the time of fixing, the digital still camera 100 (see FIG. 4) can also be reduced in size.
In the fixed state shown in FIG. 15, the holding projection of the outer frame 30 is held by the holding portion of the inner frame 20 as in the lens adapter 10 (see FIG. 9) of the first embodiment. Therefore, it is possible to prevent inadvertent return to the release state.

<5. Fifth embodiment>
[Conversion lens configuration example]

FIG. 16 is a cross-sectional view showing a fixed state of the teleconversion lens 80 as one embodiment (fifth embodiment) of the conversion lens of the present invention.
As shown in FIG. 16, the teleconversion lens 80 of the fifth embodiment is similar to the lens adapter 10 (see FIG. 10) of the first embodiment, and includes an inner frame 20, an outer frame 30, and a stopper 40. have.

Here, the inner frame 20 includes an extrapolating portion 21 that can be extrapolated to the outer peripheral surface of the lens ring 140, and a support shaft 23 that supports the stopper 40 in a swingable manner. The stopper 40 formed with the protrusion 41, the peak portion 42, and the valley portion 43 can be rotated by a seesaw-like movement around the support shaft 23, and the protrusion 41 is formed in the fixing groove 141 of the lens ring 140. coming and going.
In addition, although the support shaft 23 and the stopper 40 are provided in the position which divides the circumference of the extrapolation part 21 into 3 equally, four or more may be sufficient.

The inner frame 20 has a guide groove 24. The guide groove 24 guides the guide protrusion 31 of the outer frame 30 that is extrapolated to the inner frame 20. Therefore, the outer frame 30 can move in the optical axis direction along the guide groove 24.
The guide groove 24 has a substantially L shape similar to the lens adapter 10 (see FIG. 9) of the first embodiment. Therefore, after the outer frame 30 is moved toward the outer insertion portion 21, the outer frame 30 can be further rotated clockwise in the circumferential direction.

Furthermore, in the inner frame 20, a first lens 81, a second lens 82, and a third lens 83 (corresponding to an auxiliary lens in the present invention) are arranged along the optical axis. For this reason, by attaching the teleconversion lens 80 to the lens ring 140, it becomes possible to shoot at a high magnification.
A wide conversion lens or a macro conversion lens can be used by the lenses arranged in the inner frame 20.

  On the other hand, the outer frame 30 has a swing guide 33a and a swing guide 33b. The swing guide 33 a and the swing guide 33 b swing the stopper 40 so that the protrusion 41 enters and exits the fixing groove 141 of the lens ring 140 according to the positional relationship with the stopper 40. In addition, on the lower surface of the outer frame 30, a platform mounting portion 35 that has been subjected to D-cut processing in consideration of attachment of a tripod platform 160 is formed.

In the teleconversion lens 80 according to the fifth embodiment, the protrusion 41 of the stopper 40 is released from the fixing groove 141 of the lens ring 140 and is in a fixed state in which the protrusion 41 enters the fixing groove 141 ( (See FIG. 16).
Specifically, first, the extrapolated portion 21 of the inner frame 20 is extrapolated to the lens ring 140 in the released state.

Next, it operates so that the outer frame 30 may be moved to the optical axis direction which goes to the extrapolation part 21. FIG. As a result, the guide protrusion 31 of the outer frame 30 moves straight along the guide groove 24 of the inner frame 20.
Further, the swing guide 33a of the outer frame 30 moves away from the peak portion 42 of the stopper 40, and the swing guide 33b of the outer frame 30 comes into contact with the upper surface of the protrusion 41 of the stopper 40. As a result, the stopper 40 rotates clockwise about the support shaft 23, and the protrusion 41 fits into the fixing groove 141 of the lens ring 140.

  As described above, the teleconversion lens 80 according to the fifth embodiment operates the outer frame 30 and moves the outer frame 30 toward the outer insertion portion 21 of the inner frame 20, so that the protrusion 41 enters the fixing groove 141. It becomes a fixed state. Further, after the outer frame 30 is moved toward the extrapolating portion 21, the outer frame 30 is further rotated clockwise in the circumferential direction, whereby the lens adapter 10 of the first embodiment (see FIG. 9). Similarly, the holding projection of the outer frame 30 is held by the holding portion of the inner frame 20.

  Therefore, the teleconversion lens 80 of the fifth embodiment can be fixed to the lens ring 140 easily and reliably by one-touch two-action (movement and rotation operation of the outer frame 30). In addition, it is possible to prevent inadvertent return to the release state. Then, shooting at a high magnification becomes possible.

Further, the present invention is not limited to the above-described embodiment, and various modifications as described below are possible.
(1) In the embodiment, the lens adapters 10, 50 to 70 are attached to the digital still camera 100. Further, the tele conversion lens 80 is attached to the digital still camera. However, the lens adapters 10, 50 to 70 and the teleconversion lens 80 can be mounted on various imaging devices such as a digital video camera and a camera-equipped mobile phone.

  (2) The teleconversion lens 150 is attached to the lens adapters 10, 50 to 70 of the embodiment. However, a wide conversion lens, a macro conversion lens, a filter or the like can be attached. The conversion lens of the present invention may be not only the teleconversion lens 80 but also a wide conversion lens or a macro conversion lens.

  (3) In the lens adapters 10, 50 to 70 and the teleconversion lens 80 of the embodiment, the stoppers 40 are arranged at three positions so that the fixed portion forms a triangle. However, when it is not necessary to consider the tripod head 160, the stopper 40 may be added to four or more places so that it can withstand a large stress and can be fixed more reliably.

DESCRIPTION OF SYMBOLS 10 Lens adapter 20 Inner frame 21 Extrapolation part 22 Mounting part 23 Support shaft 24 Guide groove 25 Holding part 30 Outer frame (operation part)
31 Guide protrusion 33, 33a, 33b Oscillating guide 35 Head mounting part 40 Stopper (fixed piece)
41 Projections 42 Mountains 43 Valleys 50 Lens Adapter 51 Elastic Projections (Projections)
60 Lens adapter 63 Holding part 70 Lens adapter 74 Swing guide 80 Tele conversion lens (conversion lens)
81 First lens (auxiliary lens)
82 Second lens (auxiliary lens)
83 Third lens (auxiliary lens)
100 Digital still camera (imaging device)
130 Zoom lens unit 131 Front lens (imaging lens)
140 Lens ring 141 Fixed groove (groove)

Claims (6)

A protrusion shaped to fit into a groove formed on the outer peripheral surface of the lens ring of the imaging device;
A fixing piece on which the protrusion is formed;
A support shaft for swingably supporting the fixed piece;
A swing guide for swinging the fixed piece so that the protrusion enters and exits the groove;
An operation unit for operating the swing guide so that the protrusion enters a fixed state where the protrusion enters the groove or a release state where the protrusion protrudes from the groove;
A lens adapter having a mounting portion on which an optical component can be mounted so as to coincide with the optical axis of the imaging lens of the imaging device. The lens adapter according to claim 1,
The operation unit is movable in the optical axis direction of the imaging lens,
The swing guide is formed so that the protrusion is in the fixed state when the operation unit is moved toward the imaging device. The lens adapter according to claim 1,
The operation unit is movable in the optical axis direction of the imaging lens, and is rotatable in the circumferential direction of the imaging lens in a state where the operation unit is moved toward the imaging device.
The swing guide is formed so that the protrusion is in the fixed state when the operation unit is moved toward the imaging device. The lens adapter according to claim 1,
A lens adapter having a holding portion for holding the operation portion so as to maintain the fixed state of the protrusion. The lens adapter according to claim 1,
The protrusion is formed of a material having elasticity. A protrusion shaped to fit into a groove formed on the outer peripheral surface of the lens ring of the imaging device;
A fixing piece on which the protrusion is formed;
A support shaft for swingably supporting the fixed piece;
A swing guide for swinging the fixed piece so that the protrusion enters and exits the groove;
An operation unit for operating the swing guide so that the protrusion enters a fixed state where the protrusion enters the groove or a release state where the protrusion protrudes from the groove;
A conversion lens comprising: an auxiliary lens for changing a focal length of the imaging lens of the imaging device.

Images