JPH0220836A - Camera with zoom lens - Google Patents

Abstract

PURPOSE:To eliminate out-of-focus in case a range-finding position is slipped and when framing is changed in zoom-driving by comparing the result of a second range finding operation with the result of a first range-finding operation and updating range-finding data only when the result obtained from the second range finding operation is nearer a focal length value than a first range-finding value. CONSTITUTION:The focal length value (f) of a zoom lens 3 is adjusted by driving a zoom motor 2. While, length (l) to an object is measured by a range- finding means 4, and an object imprinting magnification (r) on a film is calculated based on the range-finding value (l) and said focal length value (f) by a calculating means 5 after zooming. Then, the range refinding is performed after zoom-driving in the way that focusing is performed in a latest position. The range-finding data is updated only when the object length (l) is near the focal length within a constant value as the result of the range refinding. Thereby focusing almost all the objects is accomplished.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a camera with a zoom lens, and more specifically, a camera with a zoom lens that has a fixed magnification function that can track a subject at a size ratio set by the photographer. Regarding the camera.

[Prior Art] Conventionally, when a photographer attempts to photograph a person or the like using a zoom lens, the photographer manually or electrically varies and sets the zoom position each time. In particular, when photographing a moving subject, for example, when photographing a skier in downhill form, it is especially important to manually or manually Moving the zoom lens for tracking using a zoom (power zoom) was a very laborious task.

Therefore, the present applicant has already developed a camera with an auto-zoom function that allows the photographer to set the ratio of the size of the human image to the photographic image frame in advance in Japanese Patent Laid-Open No. 62-251.
This was proposed in Publication No. 729 and Japanese Patent Application No. 62-53241.

[Problems to be Solved by the Invention] In the electric zoom camera of the prior application, the photographer does not have to worry about zoom operation (he can take the desired picture just by tracking the subject. Setting the ratio of the size of the subject to the image frame was done by limiting the subject to a person and assuming the person's size to be a predetermined size, such as in bust mode or full body mode. In the case of extremely small people, such as infants, the whole body will be captured even if you use bust mode.

Also, if you suddenly wanted to change the ratio, you had to cancel the auto zoom mode to take pictures at a ratio other than the set ratio.

Therefore, from the user's point of view, it is desirable to be able to freely set the size of the subject to be photographed on the film, that is, to be able to set it continuously rather than discontinuously, and to be able to easily check the ratio, and to use auto zoom. 1 without canceling
It is desirable to be able to take pictures at a uniform ratio.

However, with this configuration, if the distance is measured before auto zoom, if the subject moves while the zoom is being driven,
The camera goes out of focus. Therefore, it is better to use the data measured again after zooming, but if you use the 100 meters distance data unconditionally, if the 811 distance position shifts or if you change the framing while zooming. etc. have the disadvantage of being out of focus.

The purpose of the present invention was to solve these problems, and takes into account that when using the auto zoom shooting mode, most people approach from the front.
To provide a camera with a zoom lens that updates a measured distance value only when approaching after zoom driving.

[Means and operations for solving the problems] As shown in FIG. Focal length value f
Adjust.

On the other hand, the distance g to the subject is 711 by the distance measuring means 4.
After zooming with the zoom switch 1, the calculation means 5 calculates the imaging magnification r of the subject onto the film based on the ΔPj distance value g and the focal length value f. Further, at this time, an attitude signal is manually inputted to the calculation means 5 from the attitude determining means 8 which detects whether the photographing attitude of the camera is vertical or horizontal. This calculated printing magnification r is stored in the storage means 6. Then, based on the imprint magnification r from the storage means 6 and the measured distance value ρ from the JP1 distance means 4, the auto zoom control means 7 stores the imprint magnification r of the subject onto the film in the storage means. A focal length value f is determined so that the focal length f;IJ is controlled by the zoom motor 2 until the focal length value f;

[Example] First, prior to a detailed explanation of the present invention, the magnification of imprinting a subject onto a film will be explained.

The imprint magnification is uniquely determined by the subject pressure Ml) and the focal length f of the zoom lens. That is, as shown in FIG. 2, the height of the person 10 is y, the height of the person image 13 imaged on the film 1I012 of the camera 11 is X, and x/y [r is the printing magnification. In Figure 2, f-(x/y) ・p-r-p・・・・・・・・・(1
) holds true. In this equation (1), the size y of the person 10 at the time of photography does not change, so if you want to keep the size This means that all you have to do is change it so that it holds true. In the electric zoom camera of the earlier application,
The ratio of the size of the subject to the photographic image frame was stored in the camera in advance (111 cm), but if the image magnification was also stored in several types, for example, 35mm film When using r'-
If it is about 1730 to 1140, the photographing result will be about a bust, and if it is about -I/70 to l/80, it will be a full-body image (provided that the height of the person 10 as the subject is about 175 cI11).

By the way, if you want to set the zoom ratio yourself and memorize the imprint magnification r, you can transform the above formula (1) to obtain r-f/, lJ .・
. . . (2) Therefore, the imprint magnification r can be determined by this equation (2).

Examples of the present invention will be described below.

FIG. 3 is a block diagram of a camera with a zoom lens showing an embodiment of the present invention. AF (autofocus) 7
The 1F1 distance section 22 is independent as a distance measurement block,
Distance measurement is started according to a command from the CPU 30. In this case, distance measurement is performed using 11 pairs of data (based on a certain distance, for example, 3 m), and when the distance measurement is completed, an all down signal is sent to the CPU 30. Upon receiving this ranging end signal, the CPU 30 changes the serial clock to A.
The distance measurement data is sent to the F dl distance section 22, and in response, the distance measurement data is sent to the CPU 30 from the AF distance measurement N22 as a serial signal.
is read, and the A F J) J operation is completed.

The strobe 14 starts charging according to a signal from the CPU 30,
When charging of the strobe 14 is completed, the CPU 30 detects this and sends a charging stop signal to the strobe 14. The subsequent light emission of the strobe 14 is also performed by a signal from the CPU 30.

The ceramic oscillator 34 is for generating a basic clock for the CPU 30.

Selector switch 18°19.20 connected to CPU30
Of these, the selector switch 18 is a switch for setting the self-timer mode, the selector switch 19 is a mode selector switch for switching the shooting mode between manual zoom mode (power zoom mode) and auto zoom mode, and the selector switch 20 is a switch for setting the flash 14. This is a switch for switching the light emission to "1 dynamic flash, 1 flash prohibition 11-" and forced flash.

The photographing mode selected by these changeover switches 18 to 20 is displayed on a liquid crystal display board 21. In the self-timer mode, a light-emitting cord 15 consisting of an LED emits light to issue a warning.

Further, switches 31 and 32 are a zoom up switch and a zoom down switch, respectively.

In either manual zoom mode or auto zoom mode, pressing the zoom up switch 31 moves the zoom lens in the direction of increasing the focal length, and pressing the zoom down switch 32 moves the zoom lens in the direction of shortening the focal length. moves.

When in auto zoom mode, after this zoom
The 1ll distance is calculated, and the imprint magnification r is calculated from the 7Ill distance value and the focal length value, and this imprint magnification r is stored in the memory of the CPU 30.

The above changeover switches 18, 19.20 and zoom switch 31.32 are turned on and off in synchronization with the turning on of a power switch (not shown), which is a power switch, so that the switch input state control line 35 of the CPU 30 goes to "L" level. The reception can only be added when the

Further, a switch 36 for detecting the attitude of the camera is connected to the CPU 30. In other words, the camera body
The switch 36 detects whether the photographic image frame is in a normal posture with a horizontally elongated frame or the photographic image frame is vertically elongated, and the CPU 30 determines this.

Here, when the release button (not shown) is pressed 1- and the auto zoom mode is selected by turning on the mode changeover switch 19, the CPU 30 selects the (1-1) ) is used to calculate the focal pressure #f, and the zoom motor 24 is driven via a motor drive unit 26 consisting of an interface IC 23 which also serves as an AE (automatic exposure) +111 light unit and a bridge circuit. The position of the zoom ring 24A, which is moved by the zoom motor 24, is determined by an encoder 25 such as a photointerrupter via an interface IC 23.
Since it is fed back to the PU 30, the CPU 30
Based on the information from the encoder 25, the zoom motor 24
1. I can control q. In addition, the zoom motor 24
Since the magnification in the finder 16 changes in conjunction with this, the photographer can check the actual photographic image frame by looking through the finder 16.

Therefore, at this time, by pressing the zoom up switch 31 or the zoom down switch 32, the imprint magnification can be varied and reset.

The lens motor 27 is driven to rotate normally via the interface IC 23 and the motor drive section 26, and moves the photographing lens to the focal position calculated based on the all distance values from the AF distance measuring section 22. In this case as well, the position of the photographing lens is determined by the encoder 28 via the interface IC 23.
It is controlled by being fed back to the PU 30. Thereafter, when the release button is fully pressed, the lens motor 27 is driven in reverse to perform a shutter operation and expose the image. Thereafter, the wind motor 29 advances the film frame by frame, and the series of operations is completed.

Note that when converting the AF API distance data to lens position data, mechanical variations in the lens position, variations in the zoom coefficient, etc. may occur, but these values are stored in the E2-PROM33 as adjustment data during production. Since it is stored, the CPU 30 can calculate an accurate lens position using the AF alj distance data and the data in the E2-PROM 33.

In addition, since the interface IC23 is originally an IC for one light per Δ, the CPU 30 uses the interface IC2
Shutter control is performed based on the photometric value of step 3. In this case, what about E2-PROM33? The error of the i-1 light value is stored, and the CPU 30 stores the photometry data and the E2-PROM 33.
Calculate the correct exposure time using the data. E2-PR
Signals are exchanged between the OM 33 and the CPU 30 by serial communication for writing and reading data, and by direct line control for their status.

Next, the operation of this embodiment will be explained using flowcharts shown in FIGS. 4 to 8.

As shown in FIG. 4, when the release button Ii is pressed and the No. 1 release is turned on, the process immediately proceeds to the ill distance subroutine. In this /l1ll distance subroutine, the AF71Ilj distance section 22 performs a distance measuring operation to find the distance g to the subject. Once this distance measurement result data is stored, it is then checked to see if it is in auto zoom mode, and if it is not in auto zoom mode (if it is in manual zoom mode)
, 11P1 light is performed by the interface IC23. Then, the photographing lens is driven and moved to the in-focus position based on the subject pressure #g, which is the distance measurement data, and the second
The release is checked. When the release button is fully pressed and the second release is turned on, a check is made to see if the camera is in self-timer mode, and if it is not in self-timer mode, the exposure subroutine is executed and the photo is taken.
The film winds up and ends. In the self-timer mode, the self-timer operates and counts, and when the count ends, the exposure subroutine is executed.

When the auto zoom mode is selected by turning on the mode changeover switch 19, first, it is checked whether the camera is in a landscape orientation or a portrait orientation. The camera is usually used in a landscape orientation, but when the camera is released in a horizontal orientation like this, it is necessary to operate the zoom switch 31 or 32 before release, as will be described later. By rme CPU3
The imprint magnification r stored as 0 is used as the new imprint magnification r', and when the camera is rotated in a portrait orientation, a coefficient a is added to the imprint magnification r stored in the CPU 30. This is then set as the new printing magnification r'.

Here, if the camera is vertically oriented, the CPU 30.

The reason why the stored imprint magnification r is multiplied by the coefficient a will be explained. The coefficient a is set to a value of 1.4 to 1.5. The value of this coefficient a is the ratio of the height and width of the shooting image frame,
That is, it is the ratio of the length and width of ordinary photographic paper or 35IllW film. In other words, for photographic paper, if the vertical length is 1, then the horizontal length is 1.4, so
a-1,4/l-1,4, and for 35a+m film, the vertical length is 2411II11 and the horizontal length is 36IIII, so a-31i/24-1.5
It is. Cameras are normally used in an orientation where the image frame is horizontally elongated, but when photographing a person, for example in bust mode, it is often necessary to change the camera orientation from horizontal to vertical. It is also desirable that the size of the person be automatically adjusted to the same proportion to the photographic image frame. In other words, even if the zoom magnification of li'l- is ``,'' the ratio of the vertical size of the person in the shooting image frame will be different when the camera is oriented vertically and when it is oriented horizontally. However, when the camera is held vertically, if the person is taken a times as large as when it is held horizontally, the vertical direction of the person in the shooting frame will be the same regardless of whether the camera is held vertically or horizontally. The ratio of the size of the image can be kept constant at all times.The image magnification ``imprint magnification'' stored in the CPU 30 by operating the zoom switches 31 and 32 is based on the case where the camera is oriented horizontally.

After the imprint magnification r' is set, a subroutine for calculating the focal length f is executed based on the imprint magnification r'. That is, the above imprint magnification r' and A
The focal pressure ijf[[f is calculated from the subject distance g, which is F distance measurement data, based on the equation (1) above. A subroutine for calculating the focal length f will be described later. Next, a comparison is made between the current zoom value (focal length value), which is the focal length of 1 mm, and the auto zoom focal length f at the 1 mark position obtained by the above calculation. [If the focal pressure l11f substantially matches the focal pressure of 1 mark, it is determined that the desired auto-zoom position is already in place, and the process skips the next zoom drive process and jumps to the photometry subroutine.If the current zoom value is 11 marks The criterion (f±k) for determining whether the focal length is approximately equal to the focal length f may be, for example, ±1 pulse of the zoom encoder 25, or may be a case where the imprint magnification differs from the stored value by only a few percent. In short, it is sufficient to set a level at which the user hardly notices when the zoom lens is moved, thereby shortening the time lag of the shirt release as much as possible.
If the 8th zoom ratio is performed immediately after setting r, the subject is not moving, so the next zoom drive will not be performed and you will not miss a photo opportunity. If the distance is greater than , the zoom motor 24 will drive at high speed to change the zoom value to
Move to one target focal pressure Mf. That is, auto-zoom high-speed driving is performed. In this auto-zoom high-speed drive, the fifth
As shown in the figure, first, it is checked whether the zoom lens is at the target focal length f. Target focal pressure i
! l! If it is at position f, the zoom motor 24 is braked, then the motor is turned off and the process returns. I
If it is not at the N target focal length position, the motor 24 is driven in the forward direction when the zoom is up, and the motor 24 is driven in the reverse direction when the zoom is down. After this zoom drive, the ap1 distance is performed again. The reason for performing the n1 distance here is to check whether the subject has approached during zoom driving. That is, even if the zoom lens is moved at high speed, if the subject is a fast-moving subject or a close-distance subject, the subject may fall outside the depth of field during zoom driving. Therefore, even in such a case, the Δp1 distance is re-performed so that the camera can focus on the latest position. Then, as a result of this 71111 distance, it is checked whether the distance measurement data, that is, the subject distance g, is close within a certain value, and the Δp + distance data is updated only when the subject distance Ω is close within a certain value. do.

Here, the reason why the distance p is updated only when the subject gets closer will be described. First, since it is in auto zoom mode, most of the subjects are people. When taking pictures of people, the person should face the camera unless it is a very artistic photo.

Therefore, in most cases, if a person moves, it will be toward the camera. For example, small children
When I point my camera at them, they always run towards me, and even though I sometimes take pictures of them entering wedding ceremonies, I almost never take pictures of them exiting.

Further, even if it is desired to lock the focus during zoom driving, in the case of photographing a person, the focus is almost always locked on the person closest to the camera.

This is because simply adopting the #l-1 distance data after zoom driving may result in shifting the focus that has been achieved. For example, if a person leaves the static I distance zone, the distance measurement data will be a long distance, so such distance measurement data will not be adopted. In other words, it is a good idea to judge that the subject is approaching only when the distance is closer than the previous distance measurement. However, since the target is a person, it will not approach as quickly as possible, and for this reason,
For example, a person who runs 100 meters in 10 seconds may be set as a person who moves faster. Therefore, in order to judge whether the current /]-1 distance data is in a short distance direction with respect to the small data distance measurement data and the difference between both data is within a certain value, zoom drive time X 100n+/ l0sec −・−
A value such as ---.-(3) can be set.

After this, as in the manual zoom mode described above, photometry is performed, and then the photographing lens is driven and moved to the in-focus position based on the distance measurement data, and the second release is checked.

When the release button is fully pressed and the second release is turned on, the exposure subroutine is executed immediately if it is not in self mode, and if it is in self mode, the exposure subroutine is executed when the self timer finishes counting and the film is released. Winding is performed.

By the way, when the zoom up switch 31 or the zoom down switch 32 is pressed, a routine shown in FIG. 6 is executed. These zoom switches 31 and 32 are operated to obtain a desired imaging magnification r of the subject before pressing the release button.

When entering the routine where the switches 31 and 32 are turned on, a manual zoom subroutine is first executed. The details of this manual zoom subroutine will be described later, but while the zoom up switch 31 is on, the focal length is lengthened, and while the zoom down switch 32 is on, the focal length is shortened. The zoom lens moves to , and when switches 31 and 32 are turned off, zooming is completed. After the manual zoom subroutine is executed, a check is made to see if the auto zoom mode is active. If you are not in auto zoom mode, the process ends here. If you are in auto zoom mode, then calculate the imprint magnification r and set this to CP.
Store in U30.

That is, when the manual zooming described above is completed, perform 71P1 distance to find the distance mD to the current subject, and then use the distance g and the current zoom value f to calculate the distance (
2) Measure the imprint magnification based on the formula. Then,
Thereafter, the posture of the camera is checked, and if the camera is in a landscape orientation, the above-calculated imprint magnification r is stored as is in the CPU 30, and if the camera is in a portrait orientation, the above-mentioned imprint magnification Divide the magnification by the coefficient a and store this as the imprint magnification r.In other words, even if the camera is in a vertical orientation, the CPU 30 stores it as the imprint magnification in a horizontal orientation. .

When the zoom switch 31 or 32 is operated to perform zooming to a desired zoom position, the CPU 30 stores the imprint magnification r obtained from the aI11 distance value and focal length value after this zooming. Therefore, if the release button is then pressed, auto-zooming is performed to the zoom position where the stored printing magnification r is obtained, as described above. The memorized printing magnification will not change unless you operate the zoom switch 31 or 32 again.
The same retraction magnification r is used each time the camera is released. If it is desired to improve the imprinting ratio r, the zoom switch 31 or 32 may be operated to zoom again to the zoom position where the desired imprinting magnification r is obtained. The memorized imprint magnification r is based on the horizontal orientation of the camera, and when the camera is placed in a vertical orientation, the actual imprint magnification r' is equal to a of the imprint magnification r, as described above. Double.

The manual zoom subroutine in Figure 6 above is shown in Figure 7.
As shown in the figure. When the zoom up switch 31 or the zoom down switch 32 is pressed, the process shifts to the manual zoom flow shown in FIG. Here, first, a motor flag is set. Setting the motor flag means turning on the zoom motor 24, and resetting it means turning off the zoom motor 24. Next, the timer counter is reset and started, and is used to determine when a certain period of time has elapsed, which will be described later. Here, when the zoom up switch 31 is pressed, the zoom motor 24 rotates forward and the zoom lens is extended, and when the zoom down switch 32 is pressed, the zoom motor 24 is rotated in the reverse direction and the zoom lens is extended. be included. After the zoom motor 24 rotates in the normal or reverse direction, the motor flag is reversed and the zoom motor 24 is rotated in the normal direction until the timer counter finishes counting aF+ for a certain period of time or the zoom lens reaches the wide end or telephoto end. The rotation or reversal continues. For example, after the zoom motor 24 continues to rotate normally for a certain period of time, the timer counter is reset and started at step 11j, and the motor flag is checked. Since the motor flag has been reset by the inversion of the motor flag, the zoom motor 24 is turned off. Then, the rlj and motor flags are inverted, and the above operation is repeated after a certain period of time has elapsed. In this way, the zoom-up motor drive is performed by pulse drive with a duty ratio of 1:1 (50%). In the case of zooming down, the motor is similarly driven by pulse driving. Note that the duty ratio of the pulse drive is not limited to 1F/11, and may be changed at will as necessary, and the same applies to the drive frequency.

When the encoder 25 confirms that the zoom lens has reached the wide end or telephoto end, or the switch 31
．． 32 are off, the zoom motor 24 is turned off and the process returns to the main routine.

FIG. 8 shows a subroutine for calculating the focal length ill shown in the flowchart of FIG. 4. Regarding the flow of this subroutine, first, the set imprint (Δrate r′
and the subject distance g, which is the AF71111 distance data, the focal length i1f is calculated by 6;19. Next, this calculated focal length Hf is the minimum focal length 'M' of the zoom lens.
l~, the focal length '4f is this minimum value f
If the calculated focal length f is larger than the maximum focal length fMAX of the zoom lens, the focal length f is fixed at this maximum value fMAX. In the case of fMIN≦f≦fMΔX, the focal length of 111f is used as is. This is because the subject is too close or too far from the set printing magnification , it is impossible to set the printing magnification r'.In this case, a warning is displayed on the liquid crystal display panel 21, or a ceramic sounding element is used to produce the QJ sound. You can.

FIGS. 9(8) and 9(B) show specific configuration examples of the switch 36 for detecting the attitude of the camera. This switch 36
consists of a conductive ball 39 suspended from a support part 37 by a conductive wire 38, and a conductive member 40 arranged around the three balls, and the conductive wire 38 is connected to a resistor 4.
] is connected to the human power port of the CPU 30 in a pulled up state, and the conductive member 40 is grounded.

Now, when the camera is in its normal landscape orientation, the image shown in Figure 9 (
As shown in A), the ball 39 is hanging down due to its own weight.
The switch 36 is off because it does not contact the conductive member 40, and therefore the input port of the CPU 30 is at the "H" level. When the camera is in a vertical position, the 9th
As shown in Figure (13), the ball 39 and the conductive member 40
Since C contacts, switch 36 turns on, and therefore C
The human power port of P U 30 is at the "L0 level" and it is detected that the camera is in a vertical orientation.

[Effects of the Invention] As described above, according to the present invention, when using auto zoom, the distance measurement value is determined only when the person approaches with the front facing forward. Since we have updated the camera, we recommend using a camera with a zoom lens that can focus on most subjects.
can do.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the basic configuration of a camera with a zoom lens according to the present invention, FIG. 2 is a side view showing the relationship between the camera and the subject to explain the imprint magnification r, and FIG. A block diagram of an electric circuit of a camera with a zoom lens showing an embodiment of the present invention; FIGS. 4 to 8 are a flowchart for explaining the operation of the camera shown in FIG. 3; FIG. 9(A); (B) is an electric circuit diagram showing the configuration and operation of a switch that detects the attitude of this camera. 1...Zoom switch 2.24.
......Zoom motor 3...
...Zoom lens (photographing lens) 4...
・・・・・・l] 11 distance T stage 5・・・・・・・・・・・・
・Calculating means 6...... Storage means 7... Auto zoom control means 22
,...-A F 1llllll distance unit (71111 distance unit) 30...CPU (calculation means, storage means. Auto zoom control stage) 31...Zoom Up switch (zoom switch) 32...Zoom down switch (zoom switch)

Claims (1)

[Claims] (1) A rangefinder, a zoom lens whose focal length can be changed electrically, and a focal length that determines the focal length of the zoom lens that provides a constant magnification from the distance information to the subject obtained by the rangefinder. In a camera with a zoom lens, the camera includes a setting means and a driving means for driving and controlling the zoom lens to the determined focal length prior to photographing, a process of re-measuring the distance after the driving means finishes driving the zoom lens; A constant magnification characterized by comprising a process of comparing the remeasurement result with the original distance measurement result and updating the distance measurement data only when the remeasurement result is closer than the original distance measurement value. A camera with a zoom lens that has functions.