JPH05122569A - Camera - Google Patents

Abstract

PURPOSE:To obtain a camera equipped with a detecting means profitable for cost and a housing space which can surely detect the opening/closing state of a barrier and take a suitable countermeasure processing. CONSTITUTION:The opening/closing conditions of movable barriers 6, 7, 8 and 9 constituting the lens protecting device of this camera are detected based on the image pickup signals of a CCD 25. Namely, object beams from the barriers are passed through photographic lens 3a, 3b, 3c and 3d or the like focused to the barriers, and images are formed on the image pickup plane of the CCD 25. The image pickup signals of the barriers outputted from the CCD 25 are fetched through an A/D conversion part 26a to a system controller 26 and according to barrier luminance data based on the image pickup signals, the opening/closing states of the barriers are detected. When the opening/closing states are abnormal, the abnormality countermeasures are taken corresponding to the respective states.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera, and more particularly to an apparatus for detecting the open / closed state of a barrier for protecting the lens by opening / closing the lens in front of the taking lens.

[0002]

2. Description of the Related Art Conventionally, a movable barrier for protecting a lens such as a video camera or a still camera is usually attached to the front surface of the lens, and the movable barrier is slid or rotated in a predetermined direction. It was being opened and closed.
Since the barrier is exposed on the front surface, there is a risk that the movement thereof is blocked by a finger or the like or dust or the like is blocked by a sliding portion, and the barrier is not completely opened and closed. Therefore, it is detected that the barrier is completely opened or closed by using a detection unit such as a photo sensor or a press operation switch,
I had to confirm. Further, the barrier is arranged in the front part of the lens in the taking lens barrel, and therefore the photosensor and the like are often housed in the front outer part of the barrel.

Incidentally, as a barrier inspection apparatus of a system in which the opening / closing state of the lens protection barrier is not provided with a dedicated detecting element such as the above-mentioned photosensor or pressing switch, there is disclosed in Japanese Patent Laid-Open No. 3-9
It is proposed to be disclosed in Japanese Patent No. 0801. This device
A device for determining whether or not the clearance in the closed state of the barrier is below an allowable value from the outside to the lens protection barrier of the camera to be inspected, and the optical scanning means and the light receiving means are provided outside. ..

[0004]

However, in the conventional camera provided with the barrier detection switch, the provision of the switch for detecting the barrier open / closed state not only hinders downsizing of the outer shape of the lens barrel, The cost is also disadvantageous. That is, it is necessary to consider not only the space for arranging the switches but also the switch operating portion, and the shape of the lens barrel is limited. Further, in order to avoid the enlargement of the outer shape of the lens barrel, when the barrier is composed of two or four barriers facing each other, it is necessary to provide a switch on each barrier unit to ensure the detection operation. , And its input / output circuits are needed. Furthermore, the reliability of the switch becomes a problem.

The detection device disclosed in the above-mentioned Japanese Patent Laid-Open No. 3-90801 does not require a switch means for detecting a barrier open / closed state, but it is provided outside the device in which the barrier is incorporated. It is necessary to provide the scanning means and the light receiving means, and for example, the barrier open / closed state cannot be detected by the camera alone.

The present invention has been made in order to solve the above-mentioned inconvenience, and the output of the image pickup means is used for detecting the open / closed state of the barrier so that the detection can be performed more reliably.
Moreover, it is an object of the present invention to provide a camera that enables the lens barrel to be formed into a minimum external size, and does not require an element dedicated to the detection unit or the like and is advantageous in terms of cost.

[0007]

A camera of the present invention comprises a movable barrier for protecting a lens, a detecting means for detecting the open / closed state of the movable barrier based on the output of an image pickup means, and the detecting means. When it is detected that the movable barrier operates abnormally, the movable barrier is provided with means for performing a predetermined countermeasure against the abnormality. Also,
The opening / closing state of the movable lens protection barrier is detected based on the image pickup output.

[0008]

The state of the barrier is detected by the image pickup means, and if the movement of the barrier is abnormal, a countermeasure is taken. Further, it is detected by the output of the image pickup means that the barrier is in the open or closed state.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. FIG. 1 is a block diagram of a camera showing an embodiment of the present invention. The open / close status of the movable barriers 6, 7, 8, 9 constituting the lens protection device of the camera is determined by the image capturing means. It is assumed that it is detected by the system controller 26 having a built-in detecting means based on the image pickup signal of the CCD 25 which is an element. As shown in FIG. 1, in the present camera, the subject light is a second lens which is a first lens group 3a and a variable power lens which constitute a photographing optical system supported by a lens barrel 21.
An image is formed on the image pickup surface of a CCD 25, which is an image pickup unit, after passing through the group lens 3b, the diaphragm 22, the third group lens 3c, the fourth group lens 3d which is a focus lens, and the LPF 23 which is an optical filter. On the front surface of the first lens group 3a, as shown in a perspective view of FIG. 3, drive barriers 6 and 7 which are thin plate-shaped movable barriers constituting a lens protection device for the lens 3a and driven by the drive barriers. The movable barriers and the driven barriers 8 and 9 are rotatably arranged. Then, the image pickup signal output from the CCD 25 is subjected to processing such as amplification and sample hold by the pre-process circuit 27, and further processed by the video process circuit 28.
It is output to the recording circuit as a video signal. The pre-process circuit 27 and the video process circuit 28 are the system controller 26 including a microcomputer.
The SSG circuit (synchronization signal generation circuit) 29 controlled by S.

On the other hand, the drive barriers 6 and 7 are driven by the barrier opening / closing motor 11, and the second lens group 3b for zooming, the diaphragm 22, and the fourth lens group 3d for focusing are used.
Are each driven by the actuator group 32.
Further, the barrier opening / closing motor 11 and the actuator group 32
Is a drive circuit 3 controlled by the system controller 26.
It is driven by 3, 34. The output of the zoom encoder 24 for detecting the amount of extension of the second lens group 3b is
It is input to the system controller 26.

To detect the open / closed state of the barriers 6, 7, 8 and 9, the second and fourth lens groups are moved to the macro state, which is the closest focus position, and the image of the barrier opened / closed state is detected. Is imaged on the CCD 25. The output of the image processing signal from the pre-processing circuit 27 is captured as a luminance signal via the A / D conversion unit 26a incorporated in the system controller 26, and the capture timing is specified by the sample timing specified in the system controller 26. Only the luminance data (hereinafter referred to as barrier luminance data D) specified by the unit 26c and based on the image pickup signal corresponding to a predetermined position of the barrier described later on the image pickup screen is based on the timing designation of the vertical and horizontal synchronizing signals. To be extracted. The open / closed states of the barriers 6, 7, 8, 9 are detected from the brightness data D of the barrier image pickup signal. In addition,
Each other control element (not shown) of the camera is controlled by the system controller 26. Incidentally, in recent years, it is generally available that a microcomputer that constitutes the system controller 26 has a built-in conversion unit such as the A / D conversion unit 26a described above. Can be configured.

The close-up position focus state in the macro state when detecting the barrier open / closed state will be described with reference to FIG.
(A) shows the moving state of each lens in the close-up in-focus state of the macro state of the lens barrel. In this state, the second group lens 3b is on the wide side, and the fourth group lens 3d is
It has moved to the nearest position. Further, FIG. 2B shows a close-up in-focus state in the telescopic state, the second group lens 3b is in the tele position, and the fourth group lens 3d is moved to the close-up position. In the state of FIG. 2 (B), the closest position stays at about several tens of centimeters, but in the state of FIG. 2 (A), the closest position is from 0 cm to a few centimeters, which is just before the first lens group 3a. It is possible to properly form an image of the opened / closed state of the barriers 6, 7, 8, 9 arranged on the CCD 25 on the CCD 25 and extract the image pickup signal thereof. Furthermore, in the above-mentioned in-focus state, the depth of field is extremely shallow, and the subject outside the barrier is in a white-blurred state, which is convenient for detecting the state of the barrier. Further, at the time of detection, the diaphragm 22 is set to the open state. The state of this shooting optical system
This is referred to as "barrier focusing state".

Next, the structure of the lens protection device including the above barrier will be described with reference to FIG. The present lens protection device is a device that covers the front surface of the lens 3a with a barrier that is a lens protection member. As shown in FIG. 3, the opening / closing mechanism portion of the present device is a space formed by the outer frame 2 of the lens barrel 21 that holds the lens 3a and the camera exterior body 1 supported by the camera body (not shown). -It shall be incorporated into the space. That is, the inner diameter portion 5e of the barrier base 5 of the base member is inserted into and fixed to the ring-shaped portion 2b of the outer portion of the outer frame 2. Further, the receiving ring 4 which is a receiving member is screwed to the screw portion 2a of the outer frame 2.
Then, each member of a lens protection device described later is incorporated in the barrier base 5, and the exterior body 1 is positioned and fixed by the screw 18 in the screw hole 5g of the blade base 5 by the mounting hole 1g thereof.

Next, the structure of each member of the lens protection device will be described. First, the barrier base 5 is provided with two shaft holes 5b, and the first support shaft 15 and the second support shaft 1 are provided.
6 is rotatably inserted. The pulley 13 is fixed to one end of only the first support shaft 15. On the other hand, the first
The other ends of the two support shafts 15 and 16 are axially supported and supported by the shaft holes 1b of the exterior body 1, respectively. A barrier opening / closing motor 11 is supported by the camera body, and a pulley 12 is fixed to the output shaft of the motor 11. Then, the belt 14 is hung between the pulley 13 and the pulley 13, and the rotation of the motor 11 is transmitted to the first support shaft 15.

Driving barriers 6 and 7 are fitted and fixed to the subject side of the first and second support shafts 15 and 16 through shaft holes 6b and 7b provided at their own predetermined ends. Further, driven barriers 8 and 9 mounted on the subject side so as to be slidably stacked on the drive barriers 6 and 7 are fitted through shaft holes 8b and 9b provided at their own predetermined ends. ,
It is pivotally supported. And, in the drive barriers 6 and 7,
Gears 6a and 7a meshing with each other are fixed to the lens side so as to rotate in opposite directions. Further, pins 6c and 7c which are contact portions with the driven barriers 8 and 9 are planted near the support shaft holes of the drive barriers 6 and 7. On the side of the driven barriers 8 and 9, bottomed grooves 8c and 9c are provided at positions facing the pins 6c and 7c in the vicinity of the support shaft holes. The groove widths of the grooves 8c and 9c in the barrier rotation direction are the pins 6c and 7c.
The width c is such that it can be relatively moved by a predetermined angle with respect to the center of the spindle. Since the barriers 6 and 7 and the barriers 8 and 9 are thus interlocked with each other through the pins 6c and 7c, the driven barriers 8 and 9 are the drive barriers 6 and 7.
The driven barriers 8 and 9 have a smaller rotation angle than the driven barriers 8 and 9.

The operating state of the barrier of the lens protection device having the above construction is shown in the state diagrams of FIGS. 4 to 6 showing the relationship between the moving position and the lens opening 2c in each state of the opening / closing effective portion of each barrier. Be done. That is, during the lens protection operation, the drive barriers 6, 7 move to the advanced position (6A, 7A) in the closed state where the free ends rotate to protect the lens, and the driven barriers 8, 9 also. Also moves to the advanced position (8A, 9A) in the closed state. In the closed state, the inner edge portions 6d and 7d are in contact with each other in a state in which they overlap each other on the dividing lines of the barriers 6 and 7 in the optical axis direction by a small amount (not shown), or the inner edge portions 6d and 7d are located in the immediate vicinity and are in the closed state. Is kept. At the same time, the driven barriers 8 and 9 also have inner edge portions 8d and 9 thereof.
d becomes superposed on the outer edge portions 6e and 7e of the drive barriers 6 and 7, and further, the outer edge portions 8e and 9e are formed on the outer casing 1.
Around the opening 1c and the lens opening 2c are closed.
(See Figure 4). On the other hand, at the time of lens opening operation, the drive barriers 6 and 7 are at the retracted positions (6B, 7B) in the open state, and the driven barriers 8 and 9 are also at the retracted positions (8B, 9) in the open state.
The lens 2a is rotated and retracted, and the opening 2c of the lens 3a is opened (see FIG. 5). Further, FIG. 6 shows a state in the middle of the operation of the barrier opening / closing state, or a half-open state in which the movement of the barrier is blocked by something. In this state, the barriers 6, 7, 8, 9 are located at the intermediate positions 6c, 7c, 8c, 9c, respectively.

To detect the open / closed state of the barrier in the present camera, the photographing lens system is set to the macro closest position focusing state, that is, the barrier focusing state, and the opened / closed state of the barrier is imaged. Then, as described above, the C
After A / D conversion of the luminance component of the image pickup signal of CD25,
It is detected by loading it in the system controller 26. As a detection point of the open / closed state of the barrier, as shown in FIG.
Of the imaging points P1 to P9 in the part surrounded by the polygon,
Points P7, P8, and P9 are located on the lower side L of the barrier near the spindles 15 and 16. The luminance component of the image pickup signal corresponding to the point, that is, the barrier luminance data D
Is taken into the system controller 26 to determine the open / closed state of the barrier. FIG. 7 is a diagram showing barrier luminance data D by the image pickup signal of the point on the lower side for each operating state of the barrier. First, in the closed state of the barrier, as shown in FIG.
Since the barrier luminance data D obtained from the barrier imaging signals of 7, P8 and P9 are all off (dark state), it is determined that the barrier is closed. Further, in the open state of the barrier, as shown in FIG. 7B, points P7, P8, P
Since all the barrier luminance data D of 9 are on (bright state), it is determined that the barrier is open. Although the signal waveform of FIG. 7 is schematically shown as a constant value, the image pickup signal itself has a waveform in which both end portions are slightly lowered due to a fall in peripheral light amount or the like. On / off judgment for this is to judge the on / off by comparing with a predetermined reference value.

Then, the barrier is completely opened for some reason,
Alternatively, when the closed state is not achieved, the CCD 25
For example, the edges of the barriers 6 and 7 are imaged on the lower side of the upper image. From this, as shown in FIG. 7C, only the barrier luminance data D at the point P8 at the center of the lower side is on (bright state), or the point P7 at the end of the lower side,
When any of the barrier brightness data D of P8 and P9 is on or off, it is determined that the barrier opening / closing is incomplete. The signal HD shown in FIG. 7 represents the horizontal synchronizing signal of the image pickup signal corresponding to the video signal of the lower side of the CCD 25 corresponding to the lower side L of the points P7 to P9,
The barrier luminance data D is fetched based on this signal. This signal is a signal output from the SSG circuit 29 and serving as a timing reference for the sample timing designating section 26c. Further, in the case of the present embodiment, the data of the above-mentioned three points is taken in as the above-mentioned data D, but in the case where the memory means for recording the image signal is built in, the number of points can be further increased or the open / close state can be detailed. It is also possible to easily extract data.

With respect to the barrier opening or closing processing operation in the camera of the present embodiment configured as described above, FIG.
This will be described with reference to the flowchart of No. 9. First, we will explain the barrier opening process.This process is restarted when the power switch of the camera is turned on, when the playback mode is switched to the recording mode, or when the photographer intentionally closes the barrier. When it does, it is executed. In this process, as shown in FIG. 8, zooming process (1) is performed in step S101. This process is a process in which the photographing lens is brought into a very close focus position of the macro, that is, zooming is set to a macro and the barrier focusing state is set. Succeedingly, in a step S102, the barrier luminance data D of the points P7 to P9 are read. Based on the data D, it is determined which one of the states (A), (B) and (C) in FIG. 7 (step S103). In the closed state, the process proceeds to step S104. If it is in the open state, this processing determines that the current state of the barrier is abnormal because the barrier opening operation is being performed based on the fact that the camera recognizes that the barrier is currently closed. Then, the process jumps to step S105 to execute a subroutine "error process (1)" of FIG. 10 which will be described later.

In step S104, the barrier opening / closing motor 11 is driven to start the barrier opening operation, and after waiting a predetermined time (step S106), the data D is read again (step S107). Then, the open / close state of the barrier is determined (step S108). If the open state is confirmed, the process proceeds to step S109, the zooming process (2) is executed, and the present routine is ended. The zooming process (2) is a process of moving the photographing lens to a predetermined zooming and focusing state which is convenient for normal photographing. On the other hand, if it is still in the closed state, the process jumps to step S110 to repeat the opening operation a predetermined number of times, and thus the process returns to step S104. This is an operation of opening the barrier by repeating the opening operation several times when dust adheres to a gap or the like of the barrier drive mechanism and the movement becomes poor. If the open state does not occur even after repeating the predetermined number of times, it is determined that the movement of the barrier is abnormal, and the subroutine "error processing (2)" shown in FIG. 11 to be described later is executed.

Subroutine "Error processing (1)"
Is a process of performing an abnormality handling measure when the originally closed state is left open. In such a state, it is possible that the barrier mechanism has been destroyed, dust is stuck in the sliding part of the barrier, or the user has pry open the barrier with his or her finger, so it can be restored to normal. Whether or not to process. Figure 1
As shown in the flowchart of FIG. 0, first, the barrier close driving operation is executed for a predetermined time (step S30).
1). Then, the barrier luminance data D is fetched and its value is set as D11 (step S302). Subsequently, the open state of the barrier is determined from the data D11, and if it is in the closed state, it is considered that the operating state of the barrier has been recovered, the routine is terminated, the routine returns to the routine of FIG.
Proceed to 104. On the other hand, if it is not in the closed state, step S3
At 04, the barrier opening drive operation is executed for a predetermined time. The barrier luminance data D at that time is fetched, and the value is set as D22 (step S305). From the value D22, it is determined whether the barrier is fully opened (step S30).
6). If it is in the open state, the movement of the barrier is strange, but it is assumed that the shooting is possible for the time being, and the process proceeds to step S308, "barrier operation failure, camera shooting is possible".
Is displayed. Then, for photographing, the process returns to the routine of FIG. 8 and proceeds to step S109.

If the barrier fully closed state cannot be confirmed in the determination in step S306, the flow advances to step S307 to compare the data D11 and D22. If the two values do not change, it is determined that the barrier cannot be moved, the process proceeds to step S309, "barrier operation failure" is displayed, and this routine ends. On the other hand, if there is a change in the values D11 and D22, it is considered that there is some movement, and the opening / closing operation is performed a predetermined number of times. Therefore, the process proceeds to step S310, the number of repetitions is checked, and the step S30 is performed.
Return to 1.

Further, the subroutine "error processing (2)" is also processing for carrying out abnormality handling, and as shown in FIG. 11, it is judged whether or not the barrier is in a fully closed state (step S401). If it is not in the fully closed state, it is judged that the barrier has stopped halfway open,
"Barrier malfunction" is displayed (step S40
3), this routine ends. On the other hand, if it is in the fully closed state, it means that either the barrier cannot be opened and shooting is not possible, or that it is in a dark state where outside light cannot be obtained, and "Cannot shoot" is displayed. (Step S402), and when the barrier is not broken down, the barrier imaging data D is monitored and waits until the outside light is obtained (Step S404). It should be noted that external light is not always necessary when stroboscopic photography is performed, and stroboscopic photography can be performed so that the routine exits from this routine.

Next, the barrier closing process will be described. This process is performed before the power is turned off when the power switch of the camera is turned off.
This is executed when the recording mode is switched to the reproduction mode, or when the photographer intentionally closes the barrier. The flow chart of this processing is shown in FIG. 9, but it can be considered that this processing is performed by replacing the opening operation in the barrier opening processing shown in FIG. 8 with a closing operation. Therefore, in the description of this routine, a process different from the opening process of FIG. 8 will be mainly described. Step S201,
Step 202 is the same process as steps S101 and 102 of FIG. 8, respectively. Then, in step S203, the open / close state of the barrier is determined based on the barrier luminance data D. If the barrier is not opened, it is determined that the current state of the barrier is abnormal, the process jumps to step S205, and a subroutine "error process (3)" described later is executed. On the other hand, when the barrier is closed, it is in a normal state, and the process proceeds to steps S204 and 206 to execute the barrier closing operation for a predetermined time. In step S207, the barrier brightness data D is fetched, in step S208 it is confirmed that the barrier is fully closed, and this routine is finished. At this time, the taking lens system is
Hold the barrier focusing state as it is, and put it in a state convenient for the next barrier opening process, or
You may move to a predetermined lens position.

If it is confirmed in step S208 that the barrier has not been fully closed, step S20
The above closing drive operation is repeated a predetermined number of times via 9. However, if the fully closed state is not reached, the process proceeds to the subroutine "error process (4)". This error processing (4)
Is a process of performing an abnormality handling process corresponding to the error process (2) of FIG. 11 and a process of displaying a warning.

The error process (3) is a process for performing an abnormality handling process corresponding to the error process (1) in FIG. 10, and like the error process (1), the barrier is opened and closed a predetermined number of times. The movement of the barrier is checked by the operation such as repeating only, and when the abnormality is not recovered, the display such as "barrier operation failure" is executed.

As described above, the camera of the present embodiment does not need to be provided with a dedicated detecting means for checking the barrier movement state, and is used for photographing.
By taking in an image pickup output signal of the image of the barrier open / closed state of the CD 25 to the system controller 26, not only the open / closed state of the barrier but also the movement itself of the barrier, for example, whether it is in the half-opened state or the like can be surely detected. It is convenient to carry out the treatment.

[0028]

As described above, the camera of the present invention detects the open / closed state of the movable barrier based on the output of the image pickup means, thereby confirming the open / close state of the barrier or dealing with a predetermined abnormality of the barrier. Since the treatment can be executed, the present invention ensures that the opened / closed state of the barrier is more reliable.
In addition, it is possible to detect the degree of opening such as half-opening. Therefore, when the movement of the barrier is abnormal, appropriate countermeasure processing can be taken. Further, since the image pickup means is used, it is advantageous in terms of cost, and the arrangement space of the detecting means is also advantageous.

[Brief description of drawings]

FIG. 1 is a block diagram of a camera showing an embodiment of the present invention.

2A and 2B are diagrams showing a photographing optical system of the camera shown in FIG. 1, in which FIG. 2A shows a zooming wide state and FIG. 2B shows a zooming tele state.

FIG. 3 is an exploded perspective view of a barrier mechanism of the camera shown in FIG.

4 is a front view of the barrier mechanism of FIG. 3 in a barrier closed state.

5 is a front view of the barrier mechanism of FIG. 3 in a barrier open state.

6 is a front view of the barrier mechanism of FIG. 3 in a half-opened state of the barrier.

7 is a diagram showing a barrier luminance signal corresponding to the open / closed state of the barrier of the camera of FIG. 1, (A) showing a closed state;
(B) shows an open state, and (C) shows a half-open state.

8 is a flowchart of a "barrier opening process" of the camera shown in FIG.

9 is a flowchart of a "barrier closing process" of the camera shown in FIG.

10 is a flowchart of a subroutine "error processing (1)" called in the barrier opening processing of FIG.

FIG. 11 is a flowchart of a subroutine “error processing (2)” called in the barrier opening processing of FIG.

[Explanation of symbols]

6,7 …………………… Drive barrier (movable lens protection barrier) 8,9 ……………… Driven barrier (movable lens protection barrier) 25 ……………… CCD ( Detecting means) 26 ........................ System controller (detecting means) 26a ........................ A / D converter (detecting means) 26c ........................ Sample timing designating section (detecting means) 27 ... Preprocess circuit (detection means) S105 (S301 to S310) ... error processing (1) (abnormality countermeasure) S111 (S401 to S404) ... error processing (2) (Troubleshooting) S205 ……………… Error processing (3) (Troubleshooting) S210 ……………… Error processing (4) (Troubleshooting)

Claims (2)

[Claims] 1. A movable barrier for protecting a lens, a detection means for detecting an open / closed state of the movable barrier based on an output of an image pickup means, and an operation of the movable barrier by the detection means may be abnormal. A camera comprising: a means for performing a predetermined abnormality countermeasure when detected. 2. A camera configured to detect the open / closed state of a movable lens protection barrier based on an image pickup output.