JP2672149B2 - Video camera - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a video camera, and more specifically, in addition to zooming in a normal zoom range, super zooming is performed by inserting / removing a built-in converter lens. It relates to a video camera that is capable of.

[Conventional technology]

In a video camera with a built-in zoom lens device, the zoom lens is moved to continuously change the focal length,
You can shoot from wide-angle to telephoto (hereinafter referred to as the zoom range). By the way, in a small-sized zoom lens device mounted on a compact video camera, since the moving amount of the variable power lens cannot be increased, the variable amount of the focal length becomes small. For these reasons, compact video cameras have been dissatisfied with being unable to shoot outside the zoom range, which is generally called super wide angle or super telephoto. For this reason, in addition to the normal zooming performed by moving the zoom lens, the built-in converter lens is automatically inserted after the zoom lens is moved to a predetermined position on the optical axis, so that the zoom range outside the zoom range can be obtained. A video camera with a built-in zoom lens device capable of ultra-variable magnification has been attempted.

[Problems to be solved by the invention]

However, in the video camera described above, when switching from normal zooming to super zooming, and from super zooming to normal zooming, the converter lens is automatically inserted and removed on the optical axis. When the operation is performed, there arises a problem that, for example, an out-of-focus image or an image showing a part of the holding frame of the converter lens is recorded.

[Object of the invention]

The present invention has been made in view of the above circumstances, and does not record a disordered image due to the above operation even when a switching operation from normal zooming to super zooming or from super zooming to normal zooming is performed during recording. The purpose is to provide a video camera.

[Means for solving the problem]

To achieve the above object, the present invention achieves the above-mentioned object by recording means for recording an image by an operation signal from a recording operation part, a first sensor which is turned on when the converter lens is moved to an insertion position on the optical axis, and a converter. A second sensor which is turned on when the lens is moved to a retracted position off the optical axis; a means for outputting a switching signal when both the first sensor and the second sensor are in an off state; and the switching signal Recording control means for interrupting the recording regardless of the operation signal and restarting the recording when either the first sensor or the second sensor is turned on is output while is output.

[Operation] According to the above configuration, the switching from the normal variable power state to the super variable power state can be accurately detected by monitoring the signals from the first and second sensors, and the disturbance in the switching process. It is not necessary to record the recorded image. Moreover, when the converter lens is completely moved to the predetermined insertion position or the retracted position, the signal from the first or second sensor can be used as the recording restart signal, and the operability is improved. Further, in another invention, when the image recording is interrupted, the display means displays on the finder screen that the switching operation is in progress.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[Embodiment] In FIG. 2 showing an appearance of a video camera 2 of the present invention and FIG. 1 showing an example of a circuit of a drive control system thereof, the video camera 2 is rotatable with respect to a main body portion 3. And a grip portion 4 provided on the. A zoom lens 5 is attached to the front surface of the main body 3, and the zoom lens 5 is held by a lens barrel 6 which is divided into three parts, namely a front part, a middle part and a rear part. A front lens group 7 is fixed in the front lens barrel. In the middle lens barrel, a variable magnification lens 8, a correction lens 9, an optical axis X
In addition to the built-in wide converter 10 that can be inserted and removed freely, a beam splitter 12 and an iris 13 are also incorporated. Further, the master lens 14 is built in the rear lens barrel.

Finder 21 with a built-in CRT20 in the grip section 4
Is incorporated. An image pickup button 22 is provided on the rear surface of the grip portion 4, and a seesaw knob 2 for zooming is provided on the upper portion.
3, Super wide button 24 is provided on each side. Further, while supporting the side surface of the grip portion 4 with one hand, the imaging button 22 with the finger, the seesaw knob 23 for zooming,
A grip band 25 is attached so that the super wide button 24 can be operated.

When the seesaw knob 23 is operated, the variable magnification lens 8
Drives the stepping motor 26 to move back and forth on the optical axis X to perform zooming. The correction lens 9 moves on the optical axis X by the driving of the stepping motor 27, and corrects the movement of the focus surface due to the movement of the variable power lens 8. During normal zooming operation with the seesaw knob 23, the wide converter 10
As shown by the solid line in FIG. 1, the retracted position is from the optical axis X, and the wide converter 10 in this retracted position is confirmed by the microswitch 28. In this case, the zoom lens 5 can continuously change the focal length in the range of 9 to 54 mm by moving the variable power lens 8. When the super wide button 24 is operated, after the variable power lens 8 moves to the wide-angle end, the wide converter 10 is inserted on the optical axis X as shown by the chain double-dashed line. Confirmed by the microswitch 29. Then, in this case, the focal length is reduced to about 6 mm, which cannot be obtained by the normal zooming operation, and the object distance from 0 to infinity can be covered within the focusing range.

The beam splitter 12 takes out a part of the photographing light beam and makes it enter the distance measuring sensor 30 through a lens. The distance measuring sensor 30 constitutes a well-known phase difference detection type distance measuring device together with the AF circuit 31, and the AF circuit 31 outputs a distance measuring signal corresponding to the object distance. This distance measurement signal is input to the controller 33 via the AD converter 32. The zoom lens 5 is an inner focus type, and the stepping motor 27 is driven to move the correction lens 9 in response to the distance measurement signal to perform focusing.

An image sensor 3 such as a CCD is provided behind the master lens 14.
4 is arranged to convert the optical image obtained by the zoom lens 5 into a video signal. The image sensor 34 is connected to the video processing circuit 35. The video processing circuit 35 includes a recording circuit 38 for recording a video tape 37 and the controller 33.
CRT2 via switching transistor 36 controlled by
0 is connected.

The controller 33 is composed of a microcomputer, and performs zooming and focusing of the zoom lens 5, display of the CRT 20, driving of the recording circuit 38 and video tape 37.
Control the running of. When a zooming operation is performed using the seesaw knob 23 or the like provided on the camera body side, either the telephoto side or the wide-angle side zoom signal is output from the zoom signal generation unit 39. The controller 33 outputs a drive signal to the driver 40 in response to this zoom signal, and the stepping motor 26 rotates to either the telephoto side or the wide-angle side. By this rotation, the variable power lens 8 moves on the optical axis X to perform variable power. The position information of the variable power lens 8 is a potentiometer.
The position information is detected by 41 and is fed back to the controller 33 via the AD converter 42.

The controller 33 supplies a drive signal to the driver 43 in accordance with the position information of the variable power lens 8 to drive the stepping motor.
The position of the correction lens 9 is controlled via 27. In addition, the controller 33 operates the driver 43 based on the distance measurement signal input via the AD converter 42, and moves the correction lens 9 for focus adjustment. Therefore, the correction lens 9 is used not only for correcting the movement of the focus surface during zooming, but also for focus adjustment.

The recording circuit 38 and the recording control unit 44 are connected to the controller 33, and when the imaging button 22 is turned on, the controller 33 sends a drive signal to the recording control unit 44 which controls the recording circuit 38 and the video tape 37. Output. This recording controller
A capster motor 46 is connected to 44 via a driver 45. Further, the controller 33 is connected to a character generator 47 and a driver 48 for displaying a character image generated by the character generator 47 on the CRT 20.

The super wide button 24 is operated to obtain a super wide-angle magnification beyond the normal zoom range where zooming is performed only by moving the zoom lens 8. As a result, the super wide signal is input from the super wide signal generator 49 to the controller 33. When the controller 33 receives this super wide signal, the controller 33 outputs a drive signal to the driver 40 to move the variable power lens 8 to the wide angle end position shown in FIG. Insert at the indicated position. As a result, the focal length of the zoom lens 5 can be shortened to about 6 mm by combining the variable magnification lens 8 at the wide-angle end position and the wide converter 10.

FIG. 3 shows an embodiment of the insertion / removal mechanism of the wide converter 10. A movable frame 50 holding the variable power lens 8 is formed integrally with a sleeve 51, and the sleeve 51 is slidably attached to a guide bar 52. Further, as shown in the figure, the fork portion 50a formed on the lower end bundle of the movable frame 50 is also engaged with the guide bar 53, so that the variable magnification lens 8 is movable.
At the same time, it moves back and forth without being eccentric to the optical axis X.

Stepping motor for variable power with built-in reduction gear
26 rotates the lead screw 55. The mover 56 integrally formed with the projection 56a is screwed into the lead screw 55,
It moves back and forth according to the rotation direction of the stepping motor 26. The protrusion 56a is in contact with the protrusion 51a protruding from the sleeve 51 from the front, and the movable frame 50 biased forward by the spring 57 is positioned by the moving element 56. The fork portion of the mover 56 engages with the guide bar 59, thereby stopping the rotation of the mover 56.

A drive cam 60 is slidably attached to the guide bar 59. The drive cam 60 is provided with a partial cylindrical body 60a centered on the guide bar 61 and a cam strip 60b formed in a spiral shape on its inner surface, and is biased rearward by a spring 62. The drive cam 60 contacts the stopper 63 and normally stands by at the initial position, but when pressed by the moving element 56, it moves forward against the spring 62.

A holder 65 holding the wide converter 10 is pivotally attached to the guide bar 61 so as not to move in the front-rear direction. A stopper 65a is formed at the lower end of the holder 65. The stopper 65a turns on the micro switch 28 when the holder 65 is retracted and turns on the micro switch 29 when the holder 65 is inserted. When the micro switches 28 and 29 are turned on, a holder stop signal is output to the controller 33, and when turned off, a holder drive signal is output.

A pin 66 is provided on the side surface of the holder 65, and a bifurcated holder drive spring 68 is attached to the pin 66. The leg portions 68a, 68b of the holder drive spring 68 are biased so as to sandwich the projection 69 formed on the end surface of the sleeve integrated with the holder 65, and each end portion of the leg portions 68a, 68b has a cam line 60b of the drive cam 60. Are engaged so as to be sandwiched from both sides.

When the drive cam 60 stands by at the initial position, the wide converter 10 is at the retracted position, and when the drive cam 60 moves forward, the wide converter 10 rotates counterclockwise and the stopper 65a. When comes into contact with the guide bar 53, its rotation is stopped.

A movable frame 70 holding the correction lens 9 is slidably supported on the guide bar 61. This movable frame 70 is a spring 71
Is urged forward by. A projection 72a is provided on the sleeve 72 integrated with the movable frame 70, and the focusing moving element 73
Engages with the projection 73a. Focusing mover 73
Is screwed into a lead screw 75 that is rotated by driving the stepping motor 27, and moves forward and backward according to the rotation direction. In addition, the projection 76 of this focusing moving element 73
Is engaged with a groove formed on the inner wall of the lens barrel 6, and the focusing moving element 73 moves forward and backward without rotating.

Operation of the video camera according to the present invention
This will be described with reference to the drawings. Main switch (not shown)
When turned on, a part of the light from the subject received by the distance measuring sensor 30 is converted into an electric signal via the beam splitter 12 and sent to the AF circuit 31. Image sensor
The light from the subject reaching the light receiving surface of 34 is converted into a video signal and sent to the video processing circuit 35. The video signal processed by this video processing circuit 35 is converted into a video signal and
It is output to T20 and the recording circuit 38. Since the switching transistor 36 is in the conductive state when the main switch is ON, the image taken by the zoom lens 5 is displayed on the CRT 20 to which the video signal is output.

The controller 33 which receives the distance measurement signal from the AF circuit 31 through the AD converter 32 drives the stepping motor 27 to move the correction lens 9 to focus the zoom lens 5. When focusing is performed, a focused optical image is formed on the light receiving surface of the image sensor 34. The AF circuit 31 also outputs a focus signal to the controller 33. The controller 33, to which the focus signal is input, outputs a drive signal to the driver 48, and the character generator
The "STAND / BY" shown in FIG. 5 generated at 47 is displayed on the CRT 20 on which the image is displayed. When the image pickup button 22 is pressed in this state, the characters "REC" shown in FIG. 6 are displayed on the CRT 20. Then, from the controller 33 to the recording circuit 3
8, a record signal is output to the recording control unit 44.

The recording control unit 44 rotates the capstan motor 46 to run the video tape 37. This capstan motor 46
The video recording circuit 38, which is synchronized with, records the video signal output from the video processing circuit 35 on the video tape 37. Incidentally, the record signal is electrically locked,
When the focus signal is not output from the AF circuit 31 to the controller 33, the controller 33 does not output the record signal. Therefore, the image recorded on the video tape is not out of focus.

Seesaw knob when zooming in normal zoom range
The rotation direction of the stepping motor 26 is determined according to the operation of 23, and the mover 56 retracts during zooming to the telephoto side. As a result, the projection 56a of the mover 56 pushes the projection 51a of the sleeve 51, and the zoom lens 8 retracts together with the movable frame 50, and zooming to the telephoto side is performed.

The movement of the variable power lens 8 is detected by the potentiometer 41, and the correction lens 9 is detected from both the position information of the variable power lens 8 and the position information corresponding to the distance measurement signal from the AF circuit 11.
Is calculated. Based on the data thus calculated, the controller 33 drives the stepping motor 27,
The position control of the correction lens 9 is performed. Therefore, the focused video signal is recorded on the video tape 37.

When the super wide signal is input to the controller 33, the stepping motor 26 is driven so as to move the mover 56 forward. The movable frame 50 follows the movement of the movable element 56 as it moves forward, but when the movable frame 50 moves to the wide-angle end position that is set in front of the holder 65, the sleeve 51 moves to the stopper 78. It abuts and further advancement is restricted.

In this state, when the stepping motor 26 is further driven and the mover 56 moves forward, the mover 56 pushes the drive cam 60. In this way, when the moving cam 60 moves forward against the spring 62, the one cam leg 60b causes the leg 6 of the holder drive spring 68 to move.
8a is pressed counterclockwise. This allows the other leg
A counterclockwise biasing force is generated at 68b, and the holder 65 is rotated counterclockwise around the guide bar 61 via the protrusion 69. This rotation causes the micro switch 28 to stop 65
When the pressing of a is released, it is turned off and a holder drive signal is output to the controller 33.

The controller 33 stops the output of the record signal and turns off the switching transistor 36,
Further, the driver 48 is driven to CR the character image "W →→→ SW" generated by the character generator 47 shown in FIG.
Project on T20. Note that "W" and "SW" mean wide angle and super wide angle, respectively, and this character image indicates that the operation for switching from wide angle to super wide angle is in progress.

When the holder 65 rotates counterclockwise and the stopper 65a contacts the guide bar 53 and the micro switch 29, the wide converter 10 is aligned with the optical axis X and becomes the super wide angle state.
In the super wide-angle state in focus, the AF circuit 31 outputs a focus signal to the controller 33. And the stopper 65
A holder stop signal is output to the controller 33 from the micro switch 29 which is pressed by a and turned on.

After that, the controller 33 stops driving the driver 48, turns on the switching transistor 36, and the video signal is displayed on the CRT 20. Then, the controller 33 outputs the record signal again to the recording circuit 38 and the recording control unit 44.
Therefore, the optical image formed on the light receiving surface of the image sensor 34 in the ultra-wide-angle state is converted into a focused video signal and recorded on the video tape 37.

When returning to the normal variable magnification range, the stepping motor 26 is reversely rotated to move the mover 56 backward. Then, the drive cam 60 is retracted while following the moving element 56 by the bias of the spring 62. During this backward movement, the cam strip 60b rotates the holder 65 clockwise through the holder drive spring 68 and the protrusion 69. By this rotation, the micro switch 29 is turned off,
The holder drive signal is output to the controller 33. As described above, the controller 33 stops the recording of the video tape 37 and displays the character image "W ←←← SW" from the character generator 47 on the CRT 20.

Further, when the holder 65 rotates, the wide converter 10 moves from the optical axis X to the retracted position. In this state, the micro switch 28 is turned on and the holder stop signal is sent to the controller.
Output to 33. Therefore, the CRT20 has a zoom lens 5
The image captured in and the letters "REC" are displayed. Also, the image is recorded on the video tape 37. Thus, the wide converter 10 moves in and out on the optical axis at the time of switching between the normal variable power state and the super wide-angle state, but during the switching, the controller 33 turns off both the micro switches 28 and 29. To stop the operation of the recording circuit 38 and the recording control unit 44, and when the wide converter 10 has finished moving, it is detected that one of the micro switches 28 and 29 is turned on, and the recording circuit 38 and the recording are recorded. It functions as a recording control unit that operates the control unit 44. As a result, the distorted image during the movement of the wide converter 10 is not recorded, so that the video tape is not wasted, and when the wide converter 10 has moved to the insertion position or the retracted position, it is automatically recorded. Is restarted, so that it becomes possible to continue recording without any additional operation.

In this embodiment, when the wide converter 10 is inserted, it is switched to super-variable magnification, but when a lens having an opposite polarity is used for the wide converter 10,
The wide converter 10 may be removed.
Further, in this embodiment, the video camera that realizes super-variation using the wide converter 10 has been described, but the video camera of the present invention can realize super-variation even when a teleconverter is used.

〔The invention's effect〕

As described above, according to the video camera of the present invention, when the movable converter lens that enables super-variable magnification moves between the retracted position and the inserted position, the switching signal is output and the recording interrupting means. The image recording of the recording means driven by the operation signal is interrupted, so that the image disturbed by the switching operation is not recorded. Further, when the converter lens is completely moved to the predetermined insertion position or the retracted position, an ON signal is obtained from the first or second sensor, and this signal automatically restarts recording. Recording can be automatically continued without any additional operation.

According to another invention, in addition to the above-mentioned configuration, the viewfinder screen for displaying the recording range of the zoom lens device is provided with display means for displaying that the switching operation is being performed based on the switching signal, so that the image recording is interrupted. When this is done, it is possible to display on the finder screen that the switching operation is in progress.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an example of a control circuit of a video camera of the present invention. FIG. 2 is a perspective view showing a video camera of the present invention. FIG. 3 is a perspective view of an essential part showing an embodiment of the wide converter insertion / removal mechanism. FIG. 4 is a diagram showing a character image of the character generator displayed on the CRT. 5 and 6 are diagrams showing a video image displayed on the CRT and a character image of the character generator. 5 …… Zoom lens 7 …… Front lens 8 …… Variable lens 9 …… Compensation lens 10 …… Wide converter 26,27 …… Stepping motor 40,43 …… Driver 56 …… Motor 60 …… Drive cam 65 …… Holder.

Claims (2)

(57) [Claims] 1. A video camera capable of switching to a super variable power state by inserting and removing a converter lens with respect to the optical axis, in addition to the normal variable power for moving the variable power lens on the optical axis. Recording means for recording an image in response to an operation signal from the recording operation section, a first sensor that is turned on when the converter lens is moved to the insertion position on the optical axis, and a retracted position where the converter lens is off the optical axis. A second sensor which is turned on when the first sensor and the second sensor are both in an off state, a means for outputting a switching signal when both the first sensor and the second sensor are in an off state, and the operation while the switching signal is being output. A video camera, comprising: a recording control unit that interrupts recording regardless of a signal and restarts recording when either one of the first and second sensors is turned on. 2. The video camera according to claim 1, wherein during the switching signal is being output, a display during the switching operation is displayed on a viewfinder screen displaying a recording range of the zoom lens device. .