JP3672911B2 - Camera device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
This invention relates to a camera apparatus, in particular, relates to Luke camera apparatus be forced to infinity focus lens.
[0002]
[Prior art]
A video camera apparatus using an inner focus lens in which a front lens is fixed and a movable zoom lens and a focus lens are disposed inside the lens is known. A video camera device equipped with an inner focus lens is provided with an autofocus function. When a subject at infinity is photographed using the autofocus function, if a shielding object passes between the video camera device and the subject, the focus lens follows the shielding object. For this reason, the focus position of the focus lens changes for a short time regardless of the user's will.
[0003]
A video camera device using an inner focus lens is equipped with a focus ring and a focus volume for a manual focus function. However, since these are not physically connected to the focus lens, it is impossible to attach an index of the distance to the subject. Therefore, when a user takes a picture of a subject at infinity, it is necessary to check the position of the subject once with the viewfinder and focus on the infinity by operating the focus ring or the focus volume. .
[0004]
[Problems to be solved by the invention]
When the subject photographed by the above video camera device is reproduced, the focus on the subject is blurred by the time until the subject is focused on the shielding object and the time when the subject is focused again from the shielding object. . Further, when focusing on an object at infinity, the complicated operation as described above is required.
[0005]
Accordingly, an object of the present invention, in the video camera using an inner focus lens, it is possible to focus on infinity focus lens by a simple operation, it is possible to continue focusing on an object at infinity Luca It is to provide a mela device.
[0006]
[Means for Solving the Problems]
The present invention relates to a camera apparatus having a zoom function, an autofocus function up to infinity, and a manual focus function , a focus processing unit that detects a focus state of a captured image, a zoom detection unit that detects a zoom state, and auto-focus lens driving means driven in response to the output signal from the focusing processing unit, a manual focus lens position adjusting accepting means for accepting an adjustment of the focus lens position from the outside, depending on the state of the manual focus lens position adjustment accepting unit Manual focus lens driving means for driving the position of the focus lens, infinity focus lens driving means for driving the focus lens to an infinite focus position according to the zoom state detected by the zoom detection means , and focusing operation Control And a push switch, when the push switch is pressed while the auto-focus lens driving unit or a manual focus lens driving means is in operation, interrupt the operation of the auto-focus lens driving unit or a manual focus lens driving means, The camera device is characterized in that the infinity focus lens driving means is operated, and the focus lens is moved and held at a focus position at infinity according to the zoom state detected by the zoom detection means .
[0007]
By operating the infinity switch, the focus lens is forcibly moved to the infinity position and fixed.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a video camera apparatus according to the present invention, which comprises a control system of the apparatus, a signal processing system, and a lens control system.
[0009]
A power switch 1 for controlling the power on / off of the video camera device and a REC / STBY switch 2 for setting a shooting mode to a recording mode or a standby mode are connected to the system controller 3.
[0010]
When a subject (not shown) is photographed, a subject image enters the lens 4. The lens 4 is an inner focus lens and is configured as shown in FIG. That is, the inner focus lens 4 includes a fixed first group lens F1 and a third group lens F3, a zoom lens F2 that is a second group lens, and a focus lens F4 that is a fourth group lens. A PN filter 31 and an iris ring 32 are disposed between the zoom lens F2 and the third group lens F3. An infrared dummy glass 33 is disposed between the focus lens F4 and a CCD image sensor 5 described later. In the inner focus lens 4 having such a configuration, the optical system can be downsized.
[0011]
The subject image incident through the inner focus lens 4 is photoelectrically converted by the CCD image sensor 5 into an image signal. The luminance signal Y and the chroma signal C, which are components of the imaging signal, are supplied to the video signal processing circuit 8 via the sample hold circuit 6 and the AGC amplifier 7. In the video signal processing circuit 8, after the luminance signal Y and the chroma signal C are separated, only the luminance signal Y is supplied to the viewfinder 9. In the viewfinder 9, the video signal formed based on the luminance signal Y is monitored. Further, only the luminance signal Y is supplied from the AGC amplifier 7 to the focus processing circuit 10. The focus processing circuit 10 is composed of a high-pass filter, and a high luminance component in the luminance signal Y is extracted and a portion where the luminance is maximum is detected. Control is performed so that the focus lens F4 is moved to the portion where the luminance is maximized. The output signal of the focus processing circuit 10 is converted into a digital signal by the A / D conversion circuit 11 and supplied to the system controller 3.
[0012]
A drive signal generated by the system controller 3 based on the output signal of the A / D conversion circuit 11 is supplied to the focus driver 12. Based on the output signal of the focus driver 12, the focus motor 13 moves the focus lens F4 to the in-focus position. Further, the focus lens position sensor 20 detects the position of the focus lens F 4 and supplies the detection signal to the system controller 3 via the focus position detection circuit 21.
[0013]
The position of the zoom lens F2 is detected by the zoom lens position sensor 14, and this detection signal is converted into a digital signal by the A / D conversion circuit 16 via the zoom position detection circuit 15. The output signal of the A / D conversion circuit 16 is supplied to the system controller 3. The system controller 3 supplies a drive signal to the zoom driver 17 based on the signal supplied from the A / D conversion circuit 16. The zoom motor 18 driven by the output signal of the zoom driver 17 moves the zoom lens F2 to the optimum position.
[0014]
A TELE / WIDE switch 19 that determines the size of the subject with respect to the image frame and controls the position (wide-angle side or telephoto side) of the zoom lens F2 is connected to the system controller 3. When the TELE / WIDE switch 19 is pressed during recording, a drive signal is supplied from the system controller 3 to the zoom driver 17 according to the length of the pressing time. The output signal of the zoom driver 17 is supplied to the zoom motor 18, and the zoom lens F2 is moved to a desired position. At this time, as the zoom lens F2 moves, the focus lens F4 is moved according to a cam curve described later.
[0015]
In addition, the infinity switch 22 is connected to the system controller 3. The infinity switch 22 is a switch that supplies a high (hereinafter referred to as H) level signal to the system controller 3 when pressed. When the infinity switch 22 is pressed while the inner focus lens 4 is controlled by the autofocus function or the manual focus function, an H level signal is supplied to the system controller 3. A drive signal is supplied from the system controller 3 to the focus driver 12. A focus motor 13 is driven by the focus driver 12. Corresponding to the position of the zoom lens F2, the focus lens F4 is forcibly moved to an infinite position by the focus motor 13.
[0016]
That is, when the infinity switch 22 is pressed, the H level signal of the infinity switch 22 interrupts the autofocus function or the manual focus function, and sets the focus lens F4 to the infinity position. Therefore, by operating the infinity switch 22, even when a shielding object crosses in the vicinity of the video camera device, the position of the focus lens F4 is held at the infinity position and focused on the subject at the infinity position. The state is maintained. Further, a complicated operation for immediately photographing a subject at infinity is not necessary, and it is possible to focus the focus lens F4 to the position at infinity simply by pressing the infinity switch 22. Note that when the infinity switch 22 is pressed again, the focus lens F4 focused on the infinity position is released.
[0017]
FIG. 3 shows details of the focus lens F4. The focus lens F <b> 4 moves on the focus motor shaft 13 </ b> A attached to the focus motor 13. For example, a stepping motor is used as the focus motor 13, and the in-focus position is managed by the number of passes through the mountain of the shaft 13A.
[0018]
The inner focus lens is configured such that the focus lens F4 is moved as the zoom lens F2 is moved. For this reason, a cam curve for automatically controlling the relative position of the zoom lens F2 and the focus lens F4 is set in the system controller of the video camera device using the inner focus lens. As shown in FIG. 4, the cam curve has a different inclination depending on the in-focus distance. For this reason, a plurality of cam curves are provided to cover from close to infinity.
[0019]
FIG. 5 is a flowchart showing the operation of the infinity switch 22 described above. When the infinity switch 22 is pressed to switch to interrupt processing, it is detected whether the interrupt flag is "0" or "1" (step 41). If the interrupt flag is "0", the flag Is set to "1" (step 42). Corresponding to the flag “1”, the position of the zoom lens F2 is detected, and the A / D value corresponding to the position is read (step 43). The position of the focus lens F4 corresponding to the A / D value of the zoom lens F2 is detected (step 44), and the focus lens F4 is moved to the infinity position (step 45).
[0020]
On the other hand, if the flag is detected as “1” in step 41, the flag is returned to “0” (step 46), and the lens control operation is returned to the routine before the infinity switch 22 is pressed. (Step 47).
[0021]
【The invention's effect】
In the present invention, the focus lens is forcibly moved to the infinity position by operating the infinity switch. For this reason, when shooting an infinite subject, it is possible to start shooting immediately by simply pressing the infinity switch. Further, even if a shielding object passes in the vicinity of the video camera device, the focus position is not blurred because the position of the focus lens is fixed at infinity. Furthermore, it is possible to continue photographing an object at infinity with the video camera device fixed to a tripod or the like.
[Brief description of the drawings]
FIG. 1 is a block diagram of a video camera device according to the present invention.
FIG. 2 is a diagram showing details of an inner focus lens.
FIG. 3 is a diagram showing details of a focus lens.
FIG. 4 is a diagram showing a cam curve.
FIG. 5 is a flowchart showing the operation of the infinity switch.
[Explanation of symbols]
3 System controller 4 Inner focus lens F2 Zoom lens F4 Focus lens 22 Infinity switch

Claims (1)

In the camera device with zoom function, autofocus function up to infinity and manual focus function ,
Focus processing means for detecting a focus state of the captured image;
Zoom detection means for detecting the zoom state;
And auto-focus lens driving means driven in response to the output signal from the focusing processing means,
Manual focus lens position adjustment accepting means for accepting adjustment of the focus lens position from the outside;
Manual focus lens driving means for driving the position of the focus lens according to the state of the manual focus lens position adjustment receiving means;
Infinity focus lens driving means for driving the focus lens to a focus position at infinity according to the zoom state detected by the zoom detection means ;
A pressure switch for controlling the focus operation,
When the push switch is pressed while the auto-focus lens driving means or the manual focus lens driving means is in operation, interrupt the operation of the auto-focus lens driving means or the manual focus lens driving unit, said Infinite A camera apparatus, wherein a far focus lens driving unit operates and the focus lens is moved and held at a focus position at infinity according to a zoom state detected by the zoom detection unit .

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