JPH0367236A - Focal distance controller for camera - Google Patents

Abstract

PURPOSE:To automatically drive a photographing lens to a focal distance which is frequently used by a photographer by counting how often the photographing lens is set to the respective focal distances or a focal distance range and regarding the focal distance or any focal distance in the focal distance range to which extent the photographing lens is set most frequently as an initial focal distance. CONSTITUTION:Based on the result detected by a detection means 104, a counting means 105 counts how often and to what focal distance or what focal distance range the photographing lens is set at every focal distance or focal distance range. Based on the counted result, a selection means 106 selects the focal distance or the focal distance range to or within which the photographing lens is set most frequently and makes the selected focal distance of any focal distance in the selected focal distance range at the initial focal distance. Thereafter, when a main operation member 101 is operated, the photographing lens is automatically driven to the focal distance which is frequently used by the photographer. Thus, the deflection of the focal distance need not be newly executed after a main switch is turned on. Thus, the operability of a camera is improved.

Description

[Detailed description of the invention] A6 Industrial application fields The present invention relates to a focal length control device for a camera.

B. Prior Art Conventionally, there have been known cameras that are equipped with a main switch (main operating member) such as a power switch, and when the main switch is turned on to take a picture, the photographic lens is extended from the reset position to the wide-angle position. There is. In this type of camera, electric zooming of the photographing lens (zoom lens) and photographing are possible by operating a zoom button or a release button after the above-mentioned main switch.

Problems to be Solved by the C0 Invention Generally, photographers have a focal length that they use frequently when taking pictures. For example, a photographer who mainly takes portraits may prefer to use a focal length on the telephoto side rather than on the wide-angle side. Mainly used.

However, with conventional cameras, when the main switch is turned on, the shooting lens is uniformly driven to the wide-angle end, so photographers who frequently use the telephoto side focal length as described above cannot After turning on the switch, it is necessary to operate the zoom button to zoom up the photographic lens, which is not only cumbersome, but also poses a risk of missing a photo opportunity.

The technical problem of the present invention is that when the main switch is turned on,
The objective is to drive the photographic lens to a focal length frequently used by the photographer.

D. Means for Solving Problem 9 To explain with reference to FIG. 1, which is a diagram corresponding to the claims, the present invention comprises a main operating member 101 that is operated prior to photographing in order to put the camera in a state in which photographing is possible; Focal length change operation member 1 operated to change the focal length of the lens
02 and the main operating member 10], the photographing lens is driven to a predetermined initial focal length, and when the camera is in a shooting ready state, the focal length changing operating member 1 is operated.
When 02 is operated, the present invention is applied to a focal length control device for a camera, which includes drive means 1 and 03 that drive the photographing lens to a focal length corresponding to the operation. Based on the detection result of the detection means 104, the detection means 104 detects the focal length or focal length range of the photographic lens, and the number of times the photographic lens is set to which focal length or focal length range is detected. A counting means 105 counts for each focal length range, and based on the counting result of the counting means 105, the focal length or focal length range in which the taking lens is set the most times is selected, and the selected focal length or selected focal length is selected. and selecting means 106 for setting any focal length within the range as the initial focal length, thereby solving the above technical problem.

Based on the detection result of the detection means 104, the E0 effect counting means 105 counts for each focal length or focal length range how many times the photographing lens has been set to which focal length or focal length range. Based on this counting result, the selection means 106 selects the focal length or focal length range for which the taking lens is set the most times, and selects the selected focal length or any focal length within the selected focal length range. Set to initial focal length. Thereafter, when the main operating member Iol is operated, the photographing lens is driven to reach this initial focal length.

F. Embodiment 1 First Embodiment A first embodiment of the present invention will be described with reference to FIGS. 2 to 5.

In FIG. 2 showing the overall configuration, the control circuit 1 includes a focal length encoder 2. Motor drive circuit 3 and switch S
WI to SW4 are connected, and a zoom motor 4 is connected to the motor drive circuit 3. Here, the camera of this example is equipped with a zoom lens whose focal length is variable between 35 mm and 70 mm. focal length ranges F(1) to F(10). The focal length encoder 2 then inputs to the control circuit 1 a signal indicating which focal length range the current focal length of the photographing lens is included in.

Switches SWI and SW2 are zoom up buttons (not shown),
These are switches that are turned on in conjunction with the operation of the zoom down button, and the control circuit 1 sends a zoom up signal to the motor drive circuit 3 when the zoom switch SWI is on, and sends a zoom up signal to the motor drive circuit 3 when the switch S front 2 is on. Each outputs a down signal. The motor drive circuit 3 drives the photographic lens by the zoom motor 4 in response to the zoom up signal and the zoom down signal from the control circuit 1, and changes the focal length of the lens to the telephoto side and the wide angle side, respectively.

In other words, the 6 switch SW3 that zooms up and zooms down is a switch that is turned on in conjunction with the operation of a release button (not shown), and the control circuit 1 controls the aperture and shutter (not shown) when this switch SW3 is turned on. Drive and take pictures.

The switch SW4 is a main switch for enabling the camera to take pictures, and is turned on in conjunction with the operation of a main button (not shown). When this switch SW4 is off, the above-mentioned zooming and photographing will not be performed even if the switches SWI to SW3 are operated. When the switch SW4 is turned on, the well-known lens barrier opens and the photographic lens that has been in the reset position is extended to a predetermined photographic possible position (initial position), and then the above-mentioned switches SWI to S
Zooming and photography are possible by operating W3. The focal path M (initial focal length 1) of the photographic lens at the above-mentioned initial position is 35 mm at the wide-angle end when the camera is manufactured.
However, by operating the switches SWI and SW2 and performing zooming multiple times, it is changed as shown below.

Next, #control vB according to the flowcharts in Figures 3 to 5.
The control procedure using route 1 will be explained.

This program is started when the main switch SW4 is turned on, and the initial focal length (
(determined in step S15, which will be described later, and stored in step 816), then the lens barrier is opened in step S2, and the photographing lens is directed to the initial focal length by the motor 4 via the motor drive circuit 3 in step S3. Zoom up. Then, when it is determined in step S4 that the initial focal length has been reached, the photographing lens is stopped in step S5.

Thereafter, the process proceeds to step S6 in FIG. 3(b), where it is determined whether the zoom switch SWI or SW2 is on, and if both switches are off, it is determined whether the release switch SW3 is on or not at step S17. If the switch SW3 is off, the process returns to step S6, and if it is on, the aperture and shutter (not shown) are driven to take a picture in step 818, and then the process returns to step S6.

Also, in step S6, the zoom switch SWI is activated.

If it is determined that any one of SW2 is turned on, the process proceeds to step S7, and zooming is performed according to the turned on switch. That is, if the switch SWI is turned on, a zoom up signal is sent to the motor drive circuit 3, and the zoom up signal is sent to the motor drive circuit 3. If is on, the zoom down signal is output to each. As a result, the motor movement circuit 3 uses the motor 4 to drive the photographing lens to zoom up or zoom down.Next, in step S8, it is determined whether the switch SW1 or SW2 is still on, and if it is affirmative, the process proceeds to step S7. Go back and continue zooming, and if negative, stop zooming in step S9 and proceed to step S1
Go to 0.

In step 310, it is determined whether 8 seconds have elapsed since zooming was stopped. If negative, the states of the zoom switches SWI and SW2 are determined in step S19. switch S
If either WI or SW2 is on, step S
7, and if both are off, the process returns to step S1O. Further, if it is determined in step S10 that 8 seconds have elapsed, that is, if the focal length is held at the same value for 8 consecutive seconds, the process proceeds to step 811. Here, it is defined that when this focal length is maintained for 8 seconds, the photographic lens is set to a focal length range that includes this focal length.

In step S1l, the output signal of the focal length encoder 2 is read, and then in step 812, the number of times the photographing lens is set to the current focal length range is counted based on the read signal.

Details of this step S12 are shown in FIG. First, in step 5121, it is determined which of the above-mentioned focal length ranges F(1) to F(10) the current focal length of the photographic lens falls, based on the signal from the focal length encoder 2, and then in step 5122. Let I=1. Next, in step 5123, the focal length range F (I) and the focal length range obtained in step 5121 are compared, and if they do not match (if step 5124 is negative), then in step 8126 is incremented by "1" and returns to step 5123, where the above-described process is repeated. Also, if both focal length ranges match (step 5124
is affirmed), in step 5125, the set number of counts iN (I) is determined as rlJ? Proceed to step S13 of step f step number 3 vA(b).

That is, in the control circuit 1, each focal length range F(1) to
Variables N(1) to N(10) indicating the count value of the number of settings are stored corresponding to F(10), and according to the above processing, the number of times the shooting lens is used for each focal length range is stored. The settings are counted. In the above, the focal length range based on the output signal of the focal length encoder 2 is compared with each focal length range F(]) to F(10), and if they match, the count value corresponding to the focal length range is set to "1". '', but since the output of encoder 2 tells you which focal length range the focal length of the photographing lens is included in, you can increase the count value corresponding to that focal length range at that point. good.

In step 813, the count value TN indicating the total number of times the photographing lens is set to the above-mentioned focal length range is incremented by "1", and the process proceeds to step S14, where this count value reaches a predetermined value (100 times). Determine whether or not. Step S
If 14 is negative, the process returns to step S6, and if affirmative, the count value TN is reset to zero and the process proceeds to step S15. In step S15, the initial focal length is determined based on the number of settings obtained in step S12.

To explain with reference to FIG. 5 showing details of step S15,
First, set J=1 in step 3151, then step 5
At step 152, the number of times N(1) is set for the focal length range F(1) is read out, and the process proceeds to step 5153. In step 5153, the value of J is incremented by "1-", and then in step 51
54, the number of settings N of the focal length range F (J)
(J), and in step 5155 N(1) and N(
In step 8156, the larger value is newly set as N(1) based on the result of this size comparison, and the corresponding focal length range is newly set as F(1).
1).

Next, in step S]57, it is determined whether or not J=10, that is, whether the comparison has been completed for all focal length ranges. , focal length range F(1
) (for example, the smallest focal length) is set as the new initial focal length.

After that, the process proceeds to step S16 in FIG. 3(b),
The initial focal length determined in step S15 is stored and the process returns to step S6. Note that this program ends when the main switch SW4 is turned off.

According to the above procedure, zooming switches SW1, SW
After changing the focal length of the photographic lens by operating 2, if that focal length is maintained for 8 seconds, it is determined that the photographic lens is set to that focal length, and the focal length that includes that focal length is determined. The count value provided corresponding to the range increases (step 512), and when such focal length setting is performed a predetermined number of times, the focal length range that has been set the most times is selected from among each focal length range. A predetermined focal length within this focal length range is set as the initial focal length (step 515). This initial focal length is stored in the control circuit 1, and then the main switch SW4
When turned on, the photographic lens is driven to that initial focal length.

Therefore, for example, if the telephoto side focal length is frequently used, that telephoto side focal length will automatically become the initial focal length, and each time the main switch 4 is turned on, the photographing lens will be driven to that focal length. There is no need to perform a zooming operation when taking pictures, improving operability and reducing the chance of missing a photo opportunity. Further, if the focal length on the wide-angle side is used frequently after that, the initial focal length is automatically set to the value on the wide-angle side using the above-described procedure.

Note that the time for determining whether the photographing lens is set to an arbitrary focal length is not limited to the above-mentioned 8 seconds.

In the configuration of the above embodiment, the main switch SW4 serves as the main operation member 101, and the zoom switches SWI and SW2 serve as the focal length change operation member 102.

The motor drive circuit 3 and the zoom motor 4 form the drive means 10.
3, the focal length encoder 2 detects the detection means 104, fl
ilJ11 circuit l includes counting means 105 and selection means 10
6 respectively.

-Second example- Next, a second embodiment of the present invention will be explained with reference to FIG.

In the first embodiment, when the focal length is maintained continuously for 8 seconds, it is determined that the photographing lens is set to that focal length range, but in this embodiment, photographing is performed at a certain focal length. It is determined that the photographing lens has been set to that focal length range.

FIG. 6 shows the processing procedure of the control circuit 1 in this embodiment, and the same parts as in FIG. 3(b) are given the same reference numerals.

To explain the differences mainly, after zooming is stopped in step S9, the process returns to step S6 and the process proceeds to step 86.
- S9 are repeated, and when it is determined in step S17 that the release switch SW3 is on, step 81
Photographing is performed in step 8, and then the process of step Sll-516 (which has already been explained with reference to FIG. 3(b)) is performed.

According to the above, when photographing is performed at a given focal length, it is determined that the photographing lens is set to that focal length, and one of the above-mentioned setting times N(1) to N(10) is counted up. Therefore, the focal length that the photographer prefers can be selected more accurately as the initial focal length.

Further, FIG. 7 shows steps S21 and S22 in the process of FIG.
This shows a modified example with the addition of . That is, step 5
If 157 is affirmed, in step 821, the ratio of the largest number of settings N(1) to the total number of settings is calculated. Then, in step S22, it is determined whether the calculated ratio is greater than or equal to a predetermined value. If negative, the process returns as is; if affirmative, the initial focal length 1M is set as described above in step S22.

According to this, when the number of settings N(1) is less than a predetermined ratio, that is, 1, for example, when the setting distribution of each focal length range is averaged, 1 ± the focal length range that is set most often is Since the initial focal length is not necessarily used, the initial focal length is not updated.

Although the above example uses a zoom lens, the invention is not limited to this, and the present invention can also be applied to a case where a multifocal lens capable of photographing at a plurality of focal lengths is used. In this case, instead of setting the focal length range as described above, the number of settings may be counted for each focal length that can be photographed.

Furthermore, when the total number of times the photographing lens is set reaches a predetermined value, the initial focal length is determined according to the number of times each focal path MliiH is set. The initial focal length may be determined at the end, ie.

For example, after loading the film, the number of settings for each focal length range may be started, and when the film is removed, the initial focal length may be determined based on the number of settings. It is sufficient to determine that the film has been loaded when the film information is input from the DX code, and then to determine that the film has been removed when the back cover is opened.

Alternatively, instead of setting the initial focal length when the number of settings reaches a predetermined value, you can always check which focal length range has been set the most times, and each time set the focal length that has been set the most times as the initial focus. It may be set as a distance.

Furthermore, if the photographer determines that the initial focal length determined as described above is inconvenient to use, or if the camera is lent to a third party, the initial focal length or the current It may also have a function to cancel or temporarily suspend the contents.

FIG. 8 shows the procedure for temporarily suspending the determined initial focal length.

When a cancel switch SWC (not shown) is turned on, this program is started. First, in step S31, the current initial focal length is read out, and in step S32, it is stored in another storage area. Then, in step S33, the initial focal length (for example,
35 mm (hereinafter referred to as the initial setting value) is read out, and in step S34, this initial setting value is stored as the initial focal length from the next time onwards. Also, in this state, turn the switch SWC again.
When turned on, the focal length stored in another area in step S32 is stored again as the initial focal length from the next time. According to this, the initial focal length is temporarily reserved, which is convenient, for example, when lending the camera to a third party.

Note that the initial focal length may be permanently canceled by operating the switch SWC as described above.

G8 Effects of the Invention According to the present invention, the number of times the photographic lens is set for each focal length or focal length range is counted, and the focal length or focal length within the focal length range that has been set the most times is set as the initial value. Since the focal length is set to the focal length, when the main switch is turned on for photographing, the photographing lens is automatically driven to the focal length frequently used by the photographer. Therefore, unlike in the past, there is no need to change the focal length again after turning on the main switch, and photography can be performed immediately, improving operability and reducing the chance of missing a photo opportunity.

[Brief explanation of drawings]

FIG. 1 is a complaint correspondence diagram. 2 to 5 show a first embodiment of the present invention, FIG. 2 is a block diagram showing the overall configuration of a focal length control device according to the present invention, and FIGS. 3 to 5 show a processing procedure. flowchart,
FIG. 6 is a flowchart of the processing procedure in the second embodiment. FIGS. 7 and 8 are flowcharts showing modified examples, respectively. 1: Control circuit 2: Focal length encoder 3: Motor drive circuit 4: Zoom motor 101: Main operation member 102: Focal length change operation member 103: Driving means 104: Detection means 105: Counting means 106 = Selection means SWI, SW2: Zoom switch SW3 Nireise switch SW4: Main switch

Claims (1)

[Scope of Claims] A main operating member that is operated prior to shooting to enable the camera to take pictures; a focal length changing operating member that is operated to change the focal length of the photographic lens; When the operating member is operated, the photographing lens is driven to a predetermined initial focal length, and when the focal length changing operating member is operated while the camera is in the photographing ready state, A focal length control device for a camera comprising: a driving means for driving a photographing lens to achieve a focal length; a detecting means for detecting a focal length or a focal length range of the photographing lens; a counting means for counting for each focal length or focal length range how many times the photographic lens has been set to which focal length or focal length range; and selecting means for selecting a focal length or focal length range from a large number of focal lengths and setting the selected focal length or any one of the selected focal length ranges as the initial focal length. Camera focal length control device.