JPS5974531A - Camera having auto-focusing device - Google Patents

Abstract

PURPOSE:To perform the lens focusing driving and the camera operating driving with one motor, by calculating the extent of movement of a lens, which is required for the in-focus point of an object lens, as a forecasted value, and switching and connecting a clutch to a camera driving mechanism or a lens driving mechanism in relation to calculated result. CONSTITUTION:A distance measuring circuit 56 which calculates the extent of movement of the object lens from its current position to the infocus point is calculated by the first release signal 33; and when the forecasted value is operated, a clutch 6 is operated to connect the rotation of the motor to the lens driving mechanism, and the lens is driven, and the motor is stopped when the lens is driven in accordance with the forecasted value. When the distance measuring circuit 56 is operated and it is confirmed that a new forecasted value is within a tolerance, the clutch is connected to the camera driving mechanism side, and the motor is driven on condition that the second release signal is generated, and the shutter operation and the winding operation are performed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a camera having an automatic focus adjustment device, and more specifically, an automatic focus adjustment device configured to use one motor as a drive source to drive lens focusing and drive camera operation. The present invention relates to a camera having:

Various automatic focusing devices have already been proposed and implemented.

First, the automatic focusing device (
Japanese Patent Application No. 56-101723) will be briefly explained with reference to FIG.

The invention is an automatic focus adjustment device that performs automatic focus adjustment by moving the lens 101 forward and backward using a motor 110 based on focus adjustment information.

This device includes a motor drive circuit 116, a sensor 111 in which a number of light-receiving layers are arranged on a plane perpendicular to the optical axis of the objective lens 101, and an A-- A predicted value calculated by calculating the outputs of the D conversion 113 and the A-D conversion 113 and calculating data indicating how far the current position of the objective lens is from the in-focus position as a control measurement value of the objective lens. An arithmetic unit 114 detects the amount of movement of the lens driven by the drive circuit, and a displacement amount detector 107 and a control circuit 115
Contains.

The operation of the control circuit 115 will be explained with reference to the flowchart shown in FIG.

The control circuit 1115 activates the sensor 11 according to the AF activation signal.
1 (step 20), and the A-D conversion 113 and predicted value calculator 114 are activated (step 21).
(Step 22).

Then, the predicted value calculator 114 calculates a predicted value (N).

First, it is determined whether the predicted value (N) is within a predetermined allowable range (within No) (Ste knob 30).
.

For example, if the predicted value (N) of the calculated movement amount is zero or a value close to zero (N≦No), the lens 101 is considered to be at the end position and the focus adjustment is completed (step 31
).

If the above conditions are not satisfied, the motor drive circuit 116 is activated to drive the motor 110 (step 25).

The amount of movement of the lens 101 by the motor 110 is detected by the movement amount detector 107 (step 26).

The detected value is sent to the control circuit 115 every moment, and the control circuit 115 uses the detected value (N') and the predicted value (
N) (step 27).

When N=N', a motor drive stop signal is generated to stop the motor 110 (step 28).

Then, the above (step 20), (step 21), and (step 22) are performed, and the new predicted value (N) obtained in (step 22) is zero or a value close to zero (N≦No) in (step 30). If so, the lens 101 is considered to be at the end point position and focus adjustment is completed (step 31).
.

That is, the invention has a predicted value (N) and its predicted value (,N)
Automatic focusing of the lens is performed by repeatedly driving the lens and evaluating the results of the lens driving.

An object of the present invention is to apply the focus adjustment drive as described above to a motor drive camera, and to provide a camera having an automatic focus adjustment device that enables the focus adjustment drive and the camera concealment drive for the inspection using one motor. It is about providing.

In order to achieve the above object, a camera having an automatic focus adjustment device according to the present invention includes a motor, a camera drive mechanism that performs a series of operations such as camera release and winding by rotation of the motor, and a camera drive mechanism that performs a series of operations such as camera release and winding by rotation of the motor; a lens drive mechanism that moves the photographing release forward and backward; a lens drive amount detection device that detects the lens drive amount of the lens drive mechanism; a clutch that switches and connects the rotation of the motor to the camera drive mechanism and the lens drive mechanism; A clutch position information sensor that outputs clutch position information, a release switch that generates a first release signal when pressed down in the first stage and a second release signal when pressed down continuously, and a clutch position information sensor that outputs clutch position information; A distance measuring circuit calculates and outputs the amount of movement of the lens as a predicted value, and the distance measuring circuit is operated by the first Lullize signal, and when the predicted value is calculated, the clutch is operated to rotate the motor. is connected to the lens driving mechanism to drive the lens, the lens driving amount detection device measures the driving amount, and when driving corresponding to the predicted value is performed, the motor is stopped, and the distance measuring circuit When the new predicted value is confirmed to be within the allowable range, the clutch is activated to connect the camera drive mechanism, and the motor is driven on the condition that the second release signal is generated to release the shutter. and a control circuit that performs a winding operation and ends the camera operation on the condition that the second release signal is not generated at the end of the camera operation.

The present invention will be described in more detail below with reference to the drawings and the like. FIG. 3 is a schematic diagram for explaining an embodiment of an automatic focusing camera mechanism for carrying out the method of the present invention.

The drive motor 1 is a motor used for both lens focusing drive and camera operation drive.

The 20 rotations of the output shaft of the motor 1 are transmitted to the gear 4 through the reduced chain table row 3, and connected to the clutch gear 5 to drive it.

The clutch gear 5 is an electromagnetic cruncher that moves up and down in the figure in response to a control signal to switch power transmission.

In the figure, the clutch gear 5 is connected to the gear 7, and the driving force from the motor 1 is transmitted through the gear 7 and the gear 8 to the camera drive mechanism 9.
has been communicated to. The camera drive mechanism 9 has a known configuration including a shank, a film top, a mirror drive, and a shutter release, and should be understood as a part that executes electric camera operations other than AF (automatic focus adjustment).

When a signal is connected to the electromagnetic clutch 6 in the state shown in this figure, the clutch gear 5 moves downward, separates from the gear 7, and meshes with the lens drive gear I2, and the driving force from the motor 1 is transferred to the lens. The drive system can be switched.

The switch 10 is a switch that detects that the clutch gear 5 is in the upper position in the figure, and the switch If is a clutch position detection switch that detects that the clutch gear 5 is in the lower position.These switches form a clutch information sensor and the clutch Detects and outputs the status.

The rotation of the lens driving gear 12 is transmitted to the coupling 34 of the camera mount via the gears 13 to 20, and then to the compensation ring 24 on the lens side.

The main lens 30 is connected to a coupling 24 on the lens side via a helicoid 26, and is moved forward and backward by the rotation of the gear 25.

The light beam that has passed through the main lens 30 passes through a semi-transparent part at the center of a mirror 31 that also serves as a finder optical path, and is changed in optical path by an auxiliary mirror 32, and is then directed to a distance measuring sensor 33 (see Fig. 1) installed at the bottom of the mirror box. corresponds to the sensor 111 described in connection with ).

As described above, the focus detection calculation result (predicted value) by the distance measuring sensor 33 is output as the number of pulses (N) until focusing.

To detect the lens drive amount corresponding to the predicted value, the rotation amount of the gear 2o in the lens drive system is taken out to the perforated disk 28 via the gear 21 and the gear 22, and the rotation of this disk 28 is detected by the LED 29 and the bottom transistor. 27 and input to a control circuit (CPU) to be described later, and when the predicted value is reached, a signal is generated to stop the motor 1, the motor is temporarily stopped, and the distance measurement sensor 33 measures again. When it is confirmed that the desired movement has been performed, an output confirming completion of focus adjustment is generated. If the reconfirmation is not possible, the motor 1 is driven again.

FIG. 2 is a system block diagram of the camera.

The release button 50 is a release button that operates a switch 51 consisting of switch elements SW, 3W2,
Closing only SW, sw, , sw2 can be closed continuously.

The photometry block 53 is a well-known photometry block for automatic exposure determination, and the AE circuit 54 is the photometry block 5.
This is a circuit that determines the shutter speed and aperture value from the photometric output of No. 3 and other conditions.

The AE display section 60 is a display section that displays photometric data determined by the AE circuit 54.

The power hold section 52 is a SW of the switch 51.

This is a circuit that maintains the power of the AE circuit 54 and the distance measuring circuit 56 when the AE circuit 54 and the distance measuring circuit 56 are closed (hereinafter referred to as the time when the Lullies signal is generated).

The distance measuring circuit 56 is a circuit corresponding to the predicted value calculation circuit 114 described in connection with FIG.

The output of the distance measurement sensor 33 is connected to the distance measurement circuit 56 . The focus display section 58 is a display section that displays the output of the distance measuring circuit 56 as whether distance measurement is possible or not, and if distance measurement is possible, the calculated value (N) is divided into in-focus point, front focus, and rear focus.

Distance measurement failure may be caused by the subject itself not having enough contrast (for example, a white wall) or insufficient lighting; in the latter case, the triangular marks on both sides should be lit at a relatively large duty, and in the former case, the comparison should be made. It is designed to be lit with a small duty to distinguish between the two.

The exposure control device 61 is a circuit that controls an electromagnet that controls the rear curtain based on the output of the AE circuit 54. gate 5
Reference numeral 9 denotes a gate that determines motor drive conditions for executing the original functions of the camera.

Next, the operation of the camera will be further explained.

Press the release button 50 and turn the switch 51 to SW.

When turned on and generates the Lullies signal, the power hold circuit is activated and a bold state of the circuit power supply is formed.

This causes the AE circuit 54 to operate, calculate exposure control data, and display the data on the E display device in the viewfinder.

Further, the CPU 55 and the distance measuring device mainly involved in focus detection operate to calculate a predicted value (N) indicating how much the lens should be driven from the aforementioned current position of the lens. This step is shown in Figure 2 (Step 20).
(Step 21) Corresponds to (Step 22).

When it is impossible to calculate the predicted value (N), for example, when the subject is unpredictable, the focus display device 58 is blinked and the above-mentioned display is performed.

In this case, the clutch 57 described in connection with FIG. 3 is not operated to the lens drive side, and a standby state is formed in which the sequence does not proceed any further.

On the other hand, in the case where distance measurement is possible, the above (N) provided that N>N
When o) is obtained, a switching signal is sent to the clutch 6, and the clutch 6, which was on the camera mechanism drive side (state C), is changed to the lens drive side (state L), from top to bottom in Fig. 3. The gear 5 is moved to switch to the lens drive system.

As a result, the rotation of the motor 1 (Fig. 3) is caused by the rotation of the lens 30.
and the encoders 27, 28, 29 transmit the above (N)
The motor 1 is driven until a detection corresponding to .

This step corresponds to (step 25) shown in FIG.

As a result, the lens 30 is moved toward the focused point,
When the encoders 27, 28, and 29 detect the end of the movement (N), the motor l is stopped. This step corresponds to (step 26), (step 27), and (step 28) in FIG. 2 above.

In this state, the CPU 55 and distance measuring circuit 56 are operated to execute the above (step 20), (step 21), and (step 22), and whether the newly obtained predicted value (N) is within the predetermined tolerance range (within No). (Step 30)
). As a result, if the lens position is adjusted properly,
A circle in the center of the focus display device 58 is lit to indicate completion of focus adjustment, and a switching signal is sent to the clutch 6, changing the clutch 6 from the lens drive side (L state) to the camera mechanism drive side (C state). state), the gear 5 is moved from the bottom to the top in FIG. 3 to switch to the camera drive system.

If proper lens position adjustment is performed, the switching is not performed and distance measurement and readjustment are performed again.

When the release button 5o is pressed halfway (not shown in FIG. 4), in other words, when the SWl eye is turned on and only the first Lurise signal is generated, the clutch 6, which was on the lens drive side (L state), is moved to the camera. The predetermined sequence is ended by switching to the mechanism drive side (shape C!!3).

In other words, the focus state is memorized (fixed). Therefore, after focusing by pressing the release button halfway, you can change the composition by shifting the subject position.

Further, if refocusing is required at this stage, if you release your finger from the release button 50, swl will be turned off, all distance measurement information will be cleared, and the state will be the same as the original state.

When the Baidu release button 50 is pressed to turn SWl on, the same operation is repeated to perform distance measurement and readjustment.

After completing a predetermined sequence by switching the clutch 6 from the lens drive side (L state) to the camera intermediary drive side (C state), release button 50 is completed.
When the button is further pressed and SW1 and SW2 are turned on (a second release signal is generated), the sequence of operations of the camera mechanism is executed.

The input terminal of the gate 59 receives a focus signal indicating that focus adjustment has been completed, a clutch operation completion signal indicating that the clutch 6 has been switched to the camera side, and a second release signal, all of which are ready for use with the next camera. Execution of the motor rotation start (step 200) of the sequence of one operation is started.

When the motor rotates <step 200), the narrowing down operation begins (step 201), and at the same time, the mirror lifting operation (step 202) is performed. When the aperture is completed in accordance with the rotation of the motor and the mirror has finished rising, the tension of the front curtain is released and the front curtain starts (step 2).
03) L, a trigger SW (not shown) is operated to use this one point as a reference for exposure.

Since the AE circuit 54 has already been operated and the data for setting the appropriate exposure value (!) has been calculated, the exposure control circuit 61 determines the timing for running the rear curtain.

That is, when proper exposure is obtained, the trailing curtain holding magnet is turned off, the trailing curtain starts (step 204), and the shutter operation is completed (step 205).

This signal causes the motor 1 to start again in step 20.
6), lowering the mirror (step 207), winding the film (step 208), and simultaneously charging the shack (
Step 209) is performed.

As a result, when the winding operation is completed (step 300
), the motor 1 is stopped, and one operation of photographing the camera is completed.

At step 301), it is determined whether the first Lurise signal is being output continuously, that is, whether the photographer intends to take continuous photographs or only one shot.

If the photographer has released his/her finger from the release button 50, it is assumed that the photographer intends to take a single photo, and the power is released (step 3o3) to end the photographing operation.

On the other hand, if the release button is held down for continuous shooting, the first Lullize signal will continue to be output, so clear the distance measurement information (step 302), start distance measurement again, and repeat the above operation. Will have to repeat it again.

Since the camera according to the present invention is configured and operates as described above, it can be expected to have various operating modes as described below.

■Determining and displaying whether focus detection is possible using the second release signal; (if focus detection is possible) displaying the current position of the lens using the focus display device 58; fixing the predicted value primarily; and connecting the lens drive system using the clutch 6; (If the focus cannot be detected), a message to that effect is displayed, and the clutch 6 is not connected to the lens drive system (in this case, it is necessary to change the subject or manually adjust the focus).

(When the clutch is connected to the lens drive system) Motor 1 moves the lens until the predicted value is reached 4' Measurement and drive continue until the in-focus point is confirmed as a result of step 30. Repeated.

Please note that the subject may not move immediately after adjusting the focus.
0), if the predicted value exceeds (No), the adjustment and determination are performed again.

(When the in-focus point is confirmed), the clutch 6 is switched to the camera drive system, thereby forming a so-called focus lock state.

When the Lullies signal disappears in this state, the state returns to the state before (2).

■Operation by the second release signal The in-focus point is confirmed, the clutch connects the camera side,
When the second release signal is generated, a series of camera operations are performed by the operation of the camera mechanism.

■Continuous shooting When the first Lullize signal is generated at the end of the series of camera operations described above, the state described in (■) will occur, and as long as the release button is pressed, continuous automatic focus adjustment shooting will be performed on the condition that focus detection is possible. It will be done.

As explained above, in the device according to the present invention, the various operation modes described above can be realized by switching and using one motor using a clutch.

[Brief explanation of the drawing]

FIG. 1 is a block diagram illustrating the principle of automatic focus adjustment used in the apparatus of the present invention, and FIG. 2 is a flowchart illustrating the operation of the apparatus according to the block diagram. FIG. 3 is a schematic diagram for explaining an embodiment of the autofocus #jjlI section camera mechanism according to the present invention. FIG. 4 is a system block diagram of an autofocus camera for implementing the method of the present invention. 1...Motor 2...Pinion 3...
Reduction gear train 4...Gear 5...Clutch gear 6...Clutches 7 to 8...Camera side gear 9...Camera drive mechanism 10.11.51...Switch 12...Lens drive Gears 13 to 20... Lens drive side gear 21.22... Encoder connection gear 23.24... Coupling shaft 25... Helicoid drive gear 26... Helicoid 27... Phototransistor 28... Perforated disc 29...L E D30
...Main lens 31...Main mirror 32...
Secondary mirror 33... Distance measurement sensor 34... Coupling 50... Release button 52... Power seat-111 section 53... Photometry block 54... AE circuit 55.
...CPU 5 G...1lt11 distance circuit 58...Focus display section 59...Gate 60...AE display gB61
...Exposure control circuit patent applicant Yashica Co., Ltd. Patent attorney Hisashi Inoro

Claims (1)

[Claims] a motor, and a camera release by rotation of the motor;
a camera drive mechanism that performs a series of operations of the winding ring; a lens drive mechanism that advances and retreats the photographic release by rotation of the motor; a lens drive amount detection device that detects the amount of lens drive of the lens drive mechanism; and rotation of the motor. a clutch that switches and connects the camera drive mechanism and the lens drive mechanism; a clutch position information sensor that outputs position information of the clutch; a first-stage press down generates a first release signal; a subsequent press-down generates a second release signal; a distance measuring circuit that calculates and outputs the amount of movement of the lens required from the current position of the objective lens to the in-focus point as a predicted value; When the value is calculated, the clutch is operated to connect the rotation of the motor to the lens drive mechanism to drive the lens, and the lens drive amount detection device measures the drive amount to correspond to the predicted value. When the drive is performed, the motor is stopped, the distance measuring circuit is operated, and when it is confirmed that the new predicted value is within an allowable range, the clutch is operated to connect the camera drive mechanism side; a control circuit that drives the motor to perform a shutter winding operation on the condition that the second release signal is generated, and ends the camera operation on the condition that the second release signal is not generated at the time when the camera operation is finished; A camera having an automatic focus adjustment device comprising: