JPH06258704A - Zoom camera - Google Patents

Abstract

PURPOSE:To reduce the consumption of a power source battery and the sense of incongruity given to a photographer by preventing wasteful autofocusing action from being performed. CONSTITUTION:The camera is provided with an automatic power-off action controlling means 11(sequence controller) which automatically resets a zoom lens or multi-focus lens to a wide end when focal distance information obtained at a focal distance detecting means 8 expresses focal distance on the short focus side having low focusing sensitivity and including the wide end even through switch inputting is not performed for a specified term at a switch inputting discriminating means 11, or, which does not cancel automatic power-off action making a lens barrel collapse to a specified position but performs the automatic power-off action only when a focal distance is other than that focal distance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switch input discriminating means for discriminating whether or not a switch input has been made within a certain period of time, and the switch input discriminating means discriminating that a switch input has not been made. In this case, the present invention relates to an improvement of a zoom camera including means for automatically resetting the zoom lens to the wide end or for performing an auto power-off operation of retracting the lens barrel to a predetermined position.

[0002]

2. Description of the Related Art Recent lens shutter cameras drive zooming with an actuator such as a DC motor, and
The ones with auto focus function are the mainstream.

In this type of zoom camera, the size is further reduced as compared with the conventional model, and in order to achieve the purpose of this size reduction, the photographing optical system changes the F number and the focussing when the focal length changes. In the case of, the lens extension amount is usually changed. Therefore, a focal length detecting means for performing the F number correction and the lens extension amount correction is required, and the most common one is that the brush moves on the code pattern of the gray code in conjunction with the movement of the focal length. In addition to this, there is also a method of using a variable resistor whose output is variable in association with movement of the focal length.

However, in the camera having such a structure, there is mechanical play between the photographing optical system and the focal length detecting means, and therefore, when the zoom drive is stopped, it is always biased in a fixed direction. By doing so, this backlash is removed, and the reproducibility of the correspondence between the focal length and the output of the detection means is improved. However, if the lens barrel is moved by the photographer, this correspondence will be lost, and the focal length corresponding to the output of the focal length detection means will differ from the actual focal length, resulting in exposure shift and focusing during focusing. It may cause misalignment. Of these, the effect that is particularly large is the focus shift on the TELE side, which has high focus sensitivity.

In view of this point, as a safety measure when the lens barrel is moved, after the photographer operates the release switch or the zoom switch, no switch input is performed for a fixed time (usually about 5 minutes). If it is not performed, zoom to WIDE (wide) end or sink (collapsed position).
By providing a so-called auto power off function that automatically resets to, if the photographer subsequently shoots at a position other than the WIDE end, zooming is always performed,
The applicant of the present application has filed a prior application (Japanese Utility Model Laid-Open No. 3-60331) for canceling the backlash of the lens barrel by the one-sided drive during the stop.

FIG. 6 shows a simple circuit configuration of a zoom camera having an auto power off function.

In FIG. 5, reference numeral 51 is a sequence controller for controlling the sequence of the entire camera, 52 is a distance measuring unit for measuring the distance to the subject for autofocusing, and 53 is photometry for measuring the luminance of the subject for automatic exposure. Reference numeral 54 is a taking lens, 55 is a lens driving unit that drives the taking lens 54 during focusing, 56 is a shutter, 57 is a shutter driving circuit that drives the shutter 56, and 58 is a focal length of the taking lens 54. For detecting the focal length, 59 is a zoom motor for zooming, and 60 is the zoom motor 59.
It is a zoom motor drive circuit for driving the.

Reference numeral 61 is a release switch, and 62 is TELE.
A switch, 63 is a WIDE switch, 64 is a main switch in a release standby state (main ON) when ON, and a release prohibition state (main OFF) when OFF, 6
Reference numeral 5 is a battery that serves as a power source for the camera.

Next, an example of the structure of the focal length detecting means 58 will be described with reference to FIG. It is assumed here that the focal length detecting means 58 is a variable resistor whose output is variable in association with movement of the focal length.

In FIG. 6, 71 is a variable resistor,
Both ends are connected to a constant voltage VC (= 2.5 V) and GND, the movable contact piece moves in conjunction with zooming, and moves to the VC side during the TELE zoom and to the GND side during the WIDE zoom. Reference numeral 72 is an A / D converter for A / D converting the potential V _OUT of the movable contact piece of the variable resistor 71.

In the above structure, the potential V _OUT of the movable contact piece of the variable resistor 71 is A / D converted by the A / D converter 72,
By outputting this to the system controller 51, the focal length of the taking lens 54 can be detected by the system controller 51.

The detection result is divided into a plurality of zones in the sequence controller 51 so as to facilitate arithmetic processing. FIG. 7 shows an example of the correspondence between the potential (output) V _OUT and the focal length corresponding to the potential (output) V _OUT when this division is made into 13 zones.

In the example of FIG. 7, the focal length of the camera is "35.
~ 105 mm ", and TE is added to each divided zone.
The numbers “1 to 13” called “zoom position” are sequentially attached from the LE end.

Next, the operation relating to the automatic power-off function of the camera having the above-mentioned structure will be described with reference to the flowchart of FIG.

First, in the initial state, the camera is in a switch input standby state with the main switch 64 turned on, and enters a low current consumption mode (such as dropping the clock frequency of the microcomputer) to reduce the consumption of the battery 65. It is assumed that

In this state, the release switch 61 is turned off.
When there is a switch input such as N, the camera releases the low current consumption mode and operates according to the switch input (steps 401 → 402 → 403). For example, if the release switch 61 is turned on, the release operation is performed (at this time, the focal length detecting means 58 detects the focal length, and the calculation of the focusing position and the automatic exposure are performed according to the zoom position).

Immediately after the above operation is completed, an auto power off timer (for example, a 5-minute timer) is started (step 404), and the camera waits until the timer ends. Then, if there is any switch input during this WAIT, the operation according to the switch input is performed (step 4
04 → 405 → 403), and then the auto power-off timer is restarted from the first count number (reset value) (step 404). When there is no switch input while the auto power-off timer is counting and the timer ends, the camera automatically zooms the lens barrel to the WIDE end (steps 404 → 405 → 406 → 40).
7) After that, the mode is returned to the low current consumption mode, that is, the initial state (step 408).

[0018]

However, in the above-mentioned conventional example, the auto power-off timer is always started after the switch input such as the release operation, and
Since the number of times of automatic zooming to the WIDE end is large, battery consumption becomes faster.

In addition, the auto power off operation gives the photographer a feeling of strangeness because the camera starts moving even if nothing is touched, and the lens barrel is moved by the photographer, causing a focus shift during focusing. If it happens,
T that has a high focus sensitivity has an effect on the actual photograph appearance.
Only on the ELE side, there is almost no effect when the lens barrel is near the WIDE end, and even in such a case WI
It is useless to perform the automatic zoom to the DE end.

(Object of the Invention) A first object of the present invention is to provide a zoom camera capable of reducing consumption of a power battery and a sense of discomfort given to a photographer without performing unnecessary autofocus operation. .

A second object of the present invention is to provide a zoom camera capable of achieving power saving of a power supply battery.

[0022]

SUMMARY OF THE INVENTION The present invention is a focal length detecting means for detecting the focal length of a zoom lens or a multifocal lens, and a switch input determining means for determining whether or not a switch input has been made within a fixed time. When it is determined by the switch input determination means that no switch input is performed, the zoom lens or the multifocal lens is automatically reset to the wide end, or the lens barrel is set to a predetermined position. If the focal length information obtained by the automatic power-off operation means for performing the automatic power-off operation for collapsing and the focal length detection means is the focal length on the short focus side including the wide end, the operation by the automatic power off operation means It is equipped with an auto power off operation control means that cancels the Even if it does not exist, if the focal length information obtained by the focal length detecting means is the focal length on the short focal side including the wide end with low focus sensitivity, the zoom lens or the multifocal lens is automatically operated. The auto power-off operation of resetting to the wide end or retracting the lens barrel to a predetermined position is canceled, and is performed only at other focal lengths.

Further, a temperature detecting means for detecting the ambient temperature of the camera, a switch input determining means for determining whether or not a switch input is performed within a fixed time, and a switch input by the switch input determining means. If it is determined that there is not, an automatic power off operation means for automatically resetting the zoom lens or the multifocal lens to the wide end or for performing an automatic power off operation for retracting the lens barrel to a predetermined position. If the temperature information obtained by the temperature detecting means is below a predetermined temperature, the operation by the auto power off operation means is canceled, and if the temperature information exceeds the predetermined temperature, it is not canceled. Even if the switch input is not performed for a certain period, the temperature information obtained by the temperature detecting means is If the force characteristic is low and the temperature is lower than the specified temperature, the zoom lens or the multifocal lens is automatically reset to the wide end, or the auto power off operation to retract the lens barrel to the specified position is canceled. I have to.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on the illustrated embodiments.

FIG. 1 is a block diagram showing the circuit arrangement of a zoom camera according to the first embodiment of the present invention.
Are the same as 51 to 65 in FIG. 6, and thus the details thereof are omitted here. Further, the focal length detecting means 8 is configured as shown in FIG. 6, and as shown in FIG. 7, the detection result here is divided into a plurality of zones (13 zones) in the sequence controller 1 so as to facilitate arithmetic processing. And are associated with each other.

FIG. 2 is a flowchart showing the operation relating to the automatic power-off function of the zoom camera having the above-mentioned configuration, which will be described below.

In the initial state, the camera has the main switch 1
4 is turned on to be in a switch input standby state, and is in a low current consumption mode (for example, to reduce the clock frequency of the microcomputer) to reduce the consumption of the battery 15.

If there is a switch input such as turning on the release switch 11, the camera releases the low current consumption mode and operates according to the switch input (step 10).
1 → 102 → 103). For example, the release switch 11
If is ON, the release operation is performed.

After the above operation is completed, the focal length detecting means 8 detects the focal length (step 104) and the result is "zoom position>10", that is, the number 1
Within the three zones 1, 12, and 13 (see FIG. 7) (focal length 4
(Less than 7 mm), the zoom lens in the photographing lens 4 is located near the WIDE end, so it is determined that the auto power off operation is not necessary, and the low power consumption mode is immediately set.
That is, it returns to the initial state (step 105 → 110).

On the other hand, the focal length detected by the focal length detecting means 8 is “zoom position ≦ 10”, that is, within 10 zones of numbers 1 to 10 (focal length 47 mm or more).
If so, the auto power off timer is started and WAIT is performed until the timer ends. And this WAIT
If there is any switch input in the meantime, the operation according to the switch input is performed, and then the auto power-off timer is restarted from the first count number (reset value) (step 106 → 107 → 103 → 104 → 10
5 → 106, or steps 106 → 107 → 108 →
107 → 103 → 104 → 105 → 106).

If there is no switch input while the auto power-off timer is clocking and the timer expires,
The lens barrel (zoom lens) is automatically zoomed to the WIDE end via the zoom motor drive circuit 10 and the zoom motor 9, and then the low current consumption mode is entered, that is, the initial state is returned (step 105 → 106 → 107 → 108
→ 109 → 110).

(Second Embodiment) In the first embodiment,
If there is no switch input while the auto power off timer is counting and the timer expires, set the lens barrel to WID
Although the zoom is made to the E end, the lens barrel may be reset to the retracted position at this time. Hereinafter, this type of camera will be referred to as a second embodiment of the present invention.

FIG. 3 is a flow chart showing the operation relating to the automatic power-off function of the camera in the second embodiment, which will be described below. The circuit configuration and the like are the same as those of the first embodiment except that a retracting means for retracting the lens barrel is added, and therefore the description thereof is omitted.

In the initial state, the camera has the main switch 1
4 is turned on to be in a switch input standby state, and is in a low current consumption mode (for example, to reduce the clock frequency of the microcomputer) to reduce the consumption of the battery 15.

If there is a switch input such as turning on the release switch 11, the camera releases the low current consumption mode and operates according to the switch input (step 20).
1 → 202 → 203). For example, the release switch 11
If is ON, the release operation is performed.

After the above operation is completed, the focal length detecting means 8 detects the focal length (step 204) and the result is "zoom position>10", that is, the number 1
Within the three zones 1, 12, and 13 (see FIG. 7) (focal length 4
(Less than 7 mm), the zoom lens in the photographing lens 4 is located near the WIDE end, so it is determined that the auto power off operation is not necessary, and the low power consumption mode is immediately set.
That is, it returns to the initial state (step 205 → 210).

On the other hand, the focal length detected by the focal length detecting means 8 is "zoom position≤10", that is, within 10 zones of numbers 1 to 10 (focal length 47 mm or more).
If so, the auto power off timer is started and WAIT is performed until the timer ends. And this WAIT
If there is any switch input in the meantime, the operation according to the switch input is performed, and then the auto power off timer is restarted from the first count number (reset value) (step 206 → 207 → 203 → 204 → 20
5 → 206 or steps 206 → 207 → 208 →
207 → 203 → 204 → 205 → 206).

If there is no switch input while the auto power-off timer is clocking and the timer expires,
The lens barrel is automatically driven to the retracted position via a retracting means (not shown), and then the low current consumption mode is entered, that is, the initial state is restored (step 205 → 206 → 207 → 2).
08 → 209 → 210).

(Third Embodiment) A lithium battery or a manganese battery used as a power source for a camera has poor output characteristics at low temperatures. Therefore, if it is determined that the temperature around the camera is low, if the low power consumption mode is immediately entered without performing the automatic power-off operation, it is possible to save power when the temperature is low. Hereinafter, this type of camera is referred to as a third embodiment.

FIG. 4 is a flow chart showing the operation relating to the auto power off function of the camera in the third embodiment, which will be described below. The circuit configuration and the like are the same as those in the first embodiment except that a temperature sensor for detecting the temperature around the camera is added, and therefore the description thereof will be omitted.

In the initial state, the camera has the main switch 1
4 is turned on to be in a switch input standby state, and is in a low current consumption mode (for example, to reduce the clock frequency of the microcomputer) to reduce the consumption of the battery 15.

Here, if there is a switch input such as turning on the release switch 11, the camera releases the low current consumption mode and operates according to the switch input (step 30).
1 → 302 → 303). For example, the release switch 11
If is ON, the release operation is performed.

After the above operation is completed, the temperature TEMP around the camera obtained based on the output of the temperature sensor (not shown) is detected. If the result is "TEMP≤0 ° C.", it is for power saving. Immediately, it returns to the low current consumption mode, that is, the initial state (step 304 → 309).

On the other hand, if the temperature around the camera obtained based on the output of the temperature sensor (not shown) is “TEMP> 0 ° C.”, the auto power off timer is started and WAIT is performed until the timer ends. If there is any switch input during this WAIT, the operation according to the switch input is performed, and then the auto power off timer is restarted from the first count number (reset value) (step 305 → 306 →). 303 → 304 → 305,
Or, steps 305 → 306 → 307 → 308 → 30
7 → 303 → 304 → 305).

If there is no switch input while the auto power-off timer is counting and the timer ends,
Performs zoom reset operation to enter the low current consumption mode, that is, returns to the initial state (step 305 → 306 →
307 → 308 → 309).

Also in this embodiment, as in the first or second embodiment, the focal length detection means 8 detects the focal length, and the result is "zoom position>10".
In the case of, that is, when the zoom lens is located in the vicinity of TELE, it is possible to make the camera more convenient by automatically zooming to the WIDE end, retracting the lens barrel, and combining auto power off operation. Is possible.

According to the above first and second embodiments, the timer starts the auto power off only when the lens barrel is near TELE, and the auto power off operation is performed at the same time when the timer ends. Therefore, the battery power consumption can be reduced, and even if the lens barrel is displaced, the auto power off operation is not performed when the lens barrel is located near the WIDE end that does not affect the focus shift. There are no movements, and the sense of discomfort given to the photographer can be reduced.

Further, according to the third embodiment, when the ambient temperature of the camera is "TEMP.ltoreq..degree. C.", the low power consumption mode is immediately entered without starting the auto power off timer. Therefore, power saving can be achieved, and further power saving can be achieved by adding the above auto power off function.

[0049]

As described above, according to the present invention,
Even if the switch input is not performed for a certain period, if the focal length information obtained by the focal length detecting means is the focal length on the short focal side including the wide end with low focus sensitivity, the zoom lens is changed. The automatic power-off operation of automatically resetting to the wide end or retracting the lens barrel to a predetermined position is canceled, and is performed only at other focal lengths.

Therefore, it is possible to reduce the consumption of the power supply battery and the sense of discomfort given to the photographer without performing unnecessary autofocus operation.

Even if the switch input is not performed for a certain period, if the temperature information obtained by the temperature detecting means is below a predetermined temperature at which the output characteristic of the power supply battery becomes low, the zoom lens Is automatically reset to the wide end, or the auto power off operation for retracting the lens barrel to a predetermined position is canceled.

Therefore, power saving of the power supply battery can be achieved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a zoom camera according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing an operation of a main part of the camera shown in FIG.

FIG. 3 is a flowchart showing an operation of the zoom camera according to the second embodiment of the present invention.

FIG. 4 is a flowchart showing an operation of a zoom camera according to a third embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a conventional zoom camera.

6 is a circuit diagram showing a configuration example of a focal length detecting means of FIG.

7 is a diagram showing the relationship between the potential V _OUT , the focal length, and the zoom position in FIG.

FIG. 8 is a flowchart showing the operation of a conventional zoom camera.

[Explanation of symbols]

 1 Sequence Controller 4 Photographic Lens 8 Focal Length Detection Means 9 Zoom Motor 10 Zoom Motor Drive Circuit 11 Release Switch

Claims (3)

[Claims] 1. A focal length detecting means for detecting a focal length of a zoom lens or a multifocal lens, a switch input determining means for determining whether or not a switch input is performed within a fixed time, and the switch input determining means. If it is determined that the switch input has not been performed, the auto power off operation means for automatically resetting the zoom lens or the multifocal lens to the wide end and the focal length detection means If the obtained focal length information is the focal length on the short focal side including the wide end, the operation by the auto power off operation means is canceled, and the auto power off operation control means is not canceled at other focal lengths. Zoom camera. 2. A focal length detecting means for detecting a focal length of a zoom lens, a switch input determining means for determining whether or not a switch input is performed within a fixed time, and a switch input by the switch input determining means. If it is determined that it has not been performed, the auto power off operation means for performing the auto power off operation for retracting the lens barrel to a predetermined position, and the focal length information obtained by the focal length detection means are set at the wide end. A zoom camera provided with an auto power-off operation control means that cancels the operation by the auto power-off operation means if the focal length is on the side of the short focus side and does not cancel it at other focal lengths. 3. A temperature detecting means for detecting the ambient temperature of the camera, a switch input determining means for determining whether or not a switch input is performed within a fixed time, and a switch input is performed by the switch input determining means. If it is determined that the zoom lens or the multifocal lens has not been automatically reset to the wide end, or an auto power off operation means for performing an auto power off operation for retracting the lens barrel to a predetermined position. If the temperature information obtained by the temperature detecting means is below a predetermined temperature, the operation by the auto power off operation means is canceled, and if the temperature information exceeds the predetermined temperature, it is not canceled. Zoom camera with and.