JP3045605B2 - Camera shake detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera shake detecting device for detecting camera shake.

[0002]

2. Description of the Related Art As a conventional camera shake detection device,
Japanese Patent Publication No. 57-482 discloses a blur detection device using an AF sensor. In addition, Japanese Patent Application No. 2-3184
No. 17 discloses that infrared light is projected on the face and blur is detected by a change in the photocurrent of the reflected light.

[0003]

However, in the above-mentioned Japanese Patent Publication No. 57-482, when the environment is dark, the integration time of the sensor becomes long, and the response speed of detection does not match the blur detection. Has a drawback that blur detection during mirror up cannot be performed. In addition, Japanese Patent Application No. 2-3
In Japanese Patent No. 18417, there is a drawback that a component that does not affect the blur, such as a change in distance between the sensor and the face, is detected rather than the tilt of the camera, and the blur of the camera cannot be detected with high accuracy.

The camera shake detection apparatus of the present invention has been made in view of such a problem, and an object thereof is to provide a camera shake detection apparatus which has a simple structure and can detect camera shake even during mirror-up. It is to provide a camera shake detection device.

[0005]

In order to achieve the above object, a camera shake detecting device according to the present invention is arranged on the back of a camera, emits light toward a photographer, and reflects light from at least two points. Light receiving and receiving means for receiving light by a light receiving element and outputting a photocurrent signal corresponding to each point, and calculating means for calculating a difference of a reciprocal of a square root of the photocurrent output from the light receiving element. , The output of the arithmetic means is a camera shake signal.

[0006]

That is, the camera shake detecting apparatus of the present invention receives reflected light from at least two points of the photographer and outputs a photocurrent signal corresponding to each point. Then, the difference between the reciprocals of the square root of the output photocurrent is calculated, and the result is used as a camera shake signal.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

First, a method for detecting camera shake of the camera 10 will be described with reference to FIG. Assuming that the start of photographing is shown in FIG. 2A and that the face hardly moves during photographing, the position of the camera 10 when the camera shakes can be represented in FIG. 2B. That is, if there is camera shake, the camera 1
The rotation center of 0 moves x, and the camera 10 (sensor 12) tilts by φ.

As described in Japanese Patent Application No. 2-318417 previously filed by the present inventors, the inclination is the inclination Z between the face 14 and the camera 10 in FIG.
If the change in the distance Z ₁ / cos φ where ₁ is tilted by φ is detected, almost the tilt can be detected. The reason why the inclination may be detected is that the amount of movement of the subject on the film surface due to camera shake is βx + fφ (1) β: lateral magnification of the photographing optical system f: focal length of the photographing optical system

This is because the shake amount may be fφ because βx << fφ. But actually it faces 14 and the camera 10 is also ΔZ moved in Z ₁ direction shake.

[0011]

(Equation 1) Therefore, when camera shake is detected, it cannot be detected merely by measuring the distance between the camera 10 and the face 14.

However, since the ΔZ component has almost no effect on blur, equation (1) itself is correct. Therefore, in order to detect blur, if only the inclination φ can be detected even if the distance between the camera 10 and the face 14 changes (or if ΔZ can be detected as an amount having little effect on the inclination φ), Can be used as the blur amount.

The above method can be applied to general inclination detection. That is, as shown in FIG.
This is the case where the rotation axis of the subject 9 and the rotation axis of the tilt sensor 8 are aligned as shown in FIG. 7A, or the case where the rotation axis of the sample 9 and the rotation axis of the tilt sensor 8 are shifted as shown in FIG. Even if the distance between the tilt sensor 8 and the subject 9 changes as described above, a universal tilt sensor can be obtained if only the tilt φ can be detected. In design, even in the configuration as shown in FIG. 3A, actually, due to the variation in parts and the variation in assembly, FIG.
The configuration is as shown in FIG. Furthermore, the present inventors have discovered a sensor method for detecting only the inclination described below after repeating various trial and error.

That is, as shown in FIG. 4, a sensor having _two light receiving portions CL ₁ and CL ₂ is considered for one light projecting portion L, and the inclination is detected by the structure as shown in FIG.

First, when a light emission instruction is received from the drive circuit 1, the light emitting unit L emits light and reflects light reflected from the subject to the light receiving units CL ₁ ,
Received by the CL _2. If the light receiving currents of the light receiving sections CL ₁ and CL ₂ are i ₁ and i ₂ , the inclination is almost

[0016]

(Equation 2) Can be represented by FIG. 5 is a diagram showing a detailed configuration of an actual tilt detection circuit. The arithmetic circuit in FIG. 3 is realized by introducing the following calculation formula.

When the equation (1) is realized by analog operation,
The following calculation formula is obtained. Short-circuit current (i₁, I₂)
To eliminate such powers (here -1/2)
Where ik (arbitrary constant current) and i₁Logarithmic compression
Stretch (antilogarithmic) with flow ic. V_Tl_n(Ik / is) + V_Tl_n(I₁/ Is) = 2
V_Tl_n(Ic / is)However, V_T= KT / q… Thermal voltage is: reverse saturation current ∴ ik ・ i₁= Ic²  Next, the current to be obtained is assumed to be ic ', and V _BE (V
₁= V_BEIs expressed by ic and ik, V₁= 2V_Tl_n(Ik / is) -V_Tl_n(Ic / i
s) = V_Tl_n(Ic '/ is) ∴ ik²/ Ic = ic '. Therefore,

[0018]

(Equation 3)i_TwoCan be expressed in the same manner as the above equation. Fig. 5 shows the circuit based on the above calculation.
The figure is shown. As an example, the output V of UNiT2_OT2Ask for
You. The current ic flowing through the current mirror is V_Tl_n(Ik / is) + V_Tl_n(I_Two/ Is) = 2V_Tl_n(Ic / is) (ie, V_BE0+ V_BE2= V_BE3+ V_BE4) And ik · i_Two= Ic^Two Is established. next,
V_BE4= V_BE8V₁Is V₁= 2V_Tl_n(Ik / is) -V_Tl_n(Ic / is)

[0019] _{= V T l n (ic '} / is) ( ie,
_{V BE5 + V BE6 -V BE7 =} V BE9) to become. Since the current ic 'flowing through the resistor R is V ₁ = V _BE9 ,

[0020]

(Equation 4) Becomes Therefore, V _OT2 is

[0021]

(Equation 5) Becomes To determine the gradient output x ', since it is sufficient to V _OT2 -V _OT1, differential output V _OS is

[0022]

(Equation 6) Next, the slope x ', for example as a change in the V _OT2 -V _OT1, can be detected using a circuit as shown in Figure 6 (b).

Here, the light receiving element iPD according to the inclination direction
1 and iPD2 have a current of i ₁ > i ₂ or i ₁ <i ₂ . With this change, UNiT1, UNi
The output voltage V _OT1 and V _OT2 of T2 also maintain the relationship V _OT1> V _OT2 or V _OT1 <V _OT2. Therefore, V _OT2
When the output of −V _OT1 is changed around the reference voltage V _ref , the direction of the swing and the absolute value are easier to determine (FIG. 6).
(See (a)).

In FIG. 6B, the output V of OP4
_OS has a very small size (R ₁ = R ₂ = R ₃ =
R ₄ ), the amplification is made to a necessary and sufficient value in OP5. In this case, by connecting the filter capacitor C _L in parallel to the feedback resistor R _f, suppresses ripples.

FIG. 7 shows the minimum required functional blocks when the circuits of FIGS. 5 and 6 are converted to ic. A constant current source (i _ref ) and a constant voltage source (V _ref ) for generating the constant current (ik, ic ″) in FIG. 5 and the constant voltage (V _ref ) in FIG. 6B are added.

FIG. 8 shows a functional block in the case where a drive circuit for a light emitting section (infrared LED) is added to the function of FIG. A chip enable terminal (FuCE (bar)) is added in consideration of an interface such as a CPU. FIG. 9 shows a state when the ic of FIG. 8 is connected to the CPU 11.
The shake sensor ic causes the infrared LED (L) to emit light in response to the infrared LED drive pulse from the CPU 11, and the light reflected from the reflection surface is received by the photodiodes (CL1, CL2). Then, after a predetermined calculation process, it is output to the CPU 11 as a sensor output V _O.

FIG. 10 is a diagram showing the structure of the tilt sensor 8. FIG. 11 is a diagram showing the tilt sensor 8 (y ₀ = 13 [m
m] ), the inclination angle φ measured by using the above-described shake detection circuits of FIGS. 5 and 6, and the φ of the inclination detection circuit output V _OUT .
-V _OUT characteristic. Tilt angle φ = ± 0.256
The output V _OUT changes by about 60 [mV] with respect to [゜]. 234 mV / d for tilt angle φ = 1 [１]
5 shows the change in eg.

As is clear from FIG. 11, the inclination sensor 8
Is from 30 to 50 [mm].
In the range, the value of V _OUT becomes substantially a group and the distance Z
Is constant with respect to the deflection angle φ (V
_OUT / deg). Therefore,
If the range in which the influence of the distance Z is canceled is set as the effective range, the inclination can be detected.

Actually, the dynamic range of V _OUT is 0 ≦
If V _OUT ≤ 5.0 [V], φ = ± 10.7 [°]
(V _OUT = 2.5 [V] is assumed to be φ = ± 0 [°]). To use it as camera shake detection,
0.1 m allowable scattering circle on the film surface at f = 100 mm
To detect m, tan ^-1 (0.1 / 100) = 0.057 ° to 0.0
It suffices if an accuracy of 57 ° or less can be detected. From FIG. 11, it can be confirmed that 0.057 ° can be sufficiently detected. FIG.
Data 1 is data when a lens is arranged in front of the light projecting portion L and the diameter of the light projecting spot is reduced. FIG. 12 shows φ-V when there is no lens in front of the light projecting portion L and the light projecting angle is about ± 15 °.
_OUT characteristic.

FIG. 3 shows data in a wider angle range. Since the swing angle is large, the inclination slightly changes depending on the distance Z due to the unbalance of the projection angle and the variation of the light receiving sensitivity of the light receiving sections CL ₁ and CL ₂ , but Z> 60.
It turns out that it is stable. Although there is no group as shown in FIG. 11 irrespective of Z, the sensitivity to the angle is very strong compared to the change in distance, so that it is sufficient for tilt detection. Also, by increasing the light projection current or attaching a light projection lens as shown in FIG.
There is a detection range where Z can be ignored. Also, as shown in FIG. 12, in this embodiment, a wide angle range can be detected.

Further, when the φ-V _OUT characteristic is simply obtained by the difference i ₁ −i ₂ between the currents i ₁ and i ₂ of the light receiving sections CL ₁ and CL ₂ , the inclination of the characteristic varies with the distance Z, though not shown. Therefore, it is necessary to use it at the same time as distance detection, or to use it only at a fixed distance. Further, a case where a correlation with a camera shake signal is obtained using the tilt sensor 8 (hereinafter, referred to as a blur sensor) in FIG. 10 will be described. The camera shake signal is shown in FIG.
(A) As shown in (b), the LED of the PSD transmitting unit 50
Is received by the two-dimensional PSD 52. Since the trajectory of one point (the LED of the PSD transmitting unit 50) is followed on the two-dimensional plane, a signal equivalent to blur can be detected.

The blur sensor (sensor section 54) is a two-dimensional PS
It rotates integrally with D52 and detects the inclination with respect to the reflector 56 shown in the figure. Shake was performed by appropriately shaking the tip of the reference rod. In this embodiment, the shake corresponding to φ = ± 0.256 [°] is adjusted by the stopper 58.

FIGS. 14 (a) and 14 (b) are correlation diagrams between the y-axis of the camera shake signal (PSD) and the shake sensor when the reflection surface of the reflector 56 is flat (the y-axis direction of the PSD and the shake sensor CL). It is combined in _{1 ~L~CL 2-axis).} Although the output of the shake sensor and the camera shake signal have opposite phases, the correlation is very good. The horizontal axis of the correlation diagram indicates the offset value when the signal of the blur sensor is advanced or delayed in time, and it can be seen that there is no time delay of the blur sensor. Next, assuming a case where a person actually photographs the camera, a result obtained by correlating the camera shake signal and the shake sensor is shown below.

FIGS. 15A, 15B and 15C show examples of the experiment. As shown in FIG. 15A, the above-described two-dimensional PSD 52 is placed on the front of the camera 10 and the PSD transmitting unit 50 is provided.
The signal emitted from the LED is received as a camera shake signal. The blur sensor (sensor unit 54) is placed on the back of the camera 10 and detects a change in the tilt angle of the photographer 60 with respect to the face 62. The detection results are as follows.

That is, FIGS. 16A and 16B show the PSD.
17A and 17B show the correlation between the camera shake signal and the output of the shake sensor in the y direction (change in displacement in the y direction). FIGS. 17A and 17B show the correlation between the PSD camera shake signal and the derivative of the output in the y direction of the shake sensor (change in speed in the y direction). 18A and 18B show the correlation between the PSD hand shake signal and the change in the displacement of the shake sensor in the x direction. FIGS. 19A and 19B show the PSD hand shake signal and the change in the speed of the shake sensor in the x direction. Shows the correlation of Correlation is -200 to +60
The timing of ON / OFF of the second release is also shown for reference by using data for 0 ms. In any case, the correlation between the shake sensor and the PSD hand shake signal is very high, which confirms that the tilt detection sensor of this embodiment can be used as a shake sensor.

Hereinafter, a second embodiment of the tilt sensor will be described. It is desirable to use infrared light for the light emission and reception of the tilt sensor, but when the surroundings are bright, noise light (steady light) other than the reflected light of the light emitted to the light reception sensor is applied and the reliability of the detection data is reduced. There is. Therefore, an example of a tilt sensor detection circuit that can be used in such an environment will be described below.

FIG. 20 is a diagram showing a circuit configuration of a detection circuit having such a function of removing stationary light. SPD200 ,
Input units 201A and 201B respectively corresponding to 200B
Is a completely common circuit configuration, only 201A will be described.

The output current i ₁ from the SPD 200 is amplified by the preamplifier 100 and the amplification transistor 101 via the input terminal 300. This amplification transistor 10
The base of 1 is connected to the input of the preamplifier 100, the emitter is connected to the output of the preamplifier 100, and the collector is input to a current mirror circuit composed of PNP transistors 102 and 103. The collector of the PNP transistor 103, which is the output of the current mirror circuit, is connected to the current source 10
4, 106, the anode of the compression diode 105, the inverting input terminal of the hold amplifier 109, and the output terminal 301 of the input unit 201, and are connected to the buffer 202. The cathode of the compression diode 105 is connected to the output of the voltage follower 113 together with the cathode of the diode 107. The current source 115 and the diode 114 are connected to the non-inverting input terminal of the voltage follower 113.

The output of the voltage follower 113 is also supplied to the input section 201B. A current source 108 is connected to the anode of the diode 107, and further connected to a non-inverting input terminal of a hold amplifier 109. A hold transistor 110, a hold resistor 111, and a hold capacitor 112 are connected to the output of the hold amplifier 109 as shown. Next, the operation of the input unit 201A will be described.

The output current i ₁ from the SPD 200 is amplified by the preamplifier 100 and the amplifying transistor 101 via the input terminal 300. At this time, the stationary light current I _pa generated in the SPD 200 due to the stationary background light is also input. Have been. The operation of removing the steady photocurrent _Ipa will be described.

Here, it is assumed that the compression diode 105, the diode 107 and the diode 114 have the same characteristics, and the current sources 106 and 108 are set to the same current value. First, a steady light removing operation is performed prior to the detection of the projected light and reflected light of the IRED. Hold amplifier 10
Reference numeral 9 denotes the anode potential of the compression diode 105 and the anode potential of the diode 107, that is, the hold amplifier 10
The output voltage is determined so that the input voltages at the inverting input terminal and the non-inverting input terminal of the Ninth Input Unit 9 are equal. When the steady light current _Ipa is amplified by the preamplifier 100 and the amplification transistor 101, the current flows into the compression diode 105 via the current mirror circuit including the PNP transistors 102 and 103, and the cathode potential of the compression diode 105 is increased. Then, the potential of the inverting input terminal of the hold amplifier 109 also rises.
, The base potential of the hold transistor 110 rises, and the steady-state photocurrent _Ipa flows to the ground as a collector current via the hold resistor 41A.

By such a feedback action, the steady photocurrent I
_pa is removed and flows to the ground and is not amplified. The output voltage of the hold amplifier 109 corresponding to the level of the steady light current _Ipa is
Is stored. The bias current of the amplifying transistor 101 is provided by the current source 104, and the state where no current flows at the point A 'in the figure is maintained by the above-described steady light removing operation. Next, the operation at the time of detecting the IRED emission and the reflected light will be described.

The hold amplifier 109 by simultaneously with the emission of the IRED holdoff signal T _H stops its function,
Also, the current source 106 is turned off. Here, since the hold capacitor 112 holds the charge for removing the steady light as described above, the signal current i _{1 of the} SPD 200 generated by the reflected light is removed by the preamplifier 100 and the amplification while the steady light current I _pa is removed. The signal is amplified by the transistor 101, passes through a current mirror circuit including PNP transistors 102 and 103, and further passes through a point A 'in FIG.
A signal current flows through the compression diode 105. Therefore, the anode potential of the compression diode 105, that is, the input section 20
The output voltage V ₀ of the first output terminal 301 can be expressed by the following equation.

[0044]

(Equation 7)

The output 301 of the input unit 201A is
It is input to the above-mentioned UNiT ₁ via 02A (see FIG. 5). Circuits subsequent to UNiT1 are the same as those shown in FIG. 5 and FIG. Here, an example in which the stationary light is cut has been described.

As another method of cutting off the stationary light, it is conceivable to increase the light amount of the light projecting section much more than that of the stationary light. However, normally, there is a limit to the amount of current that can flow through the light-emitting LED in a steady state. Therefore, if light is emitted in a pulsed manner only at the timing of blur detection, the light amount of the light-emitting portion can be increased. Although not specifically described here, this technique is generally used as a method for increasing the light amount of the active AF. FIG. 21 is a block diagram of a TTL single-lens reflex camera incorporating a shake detection apparatus according to one embodiment of the present invention.

The main CPU 901 sequentially executes sequential control based on a program stored in a ROM provided therein, thereby controlling operations of peripheral ICs and the like. The AFIC 907 is a general distance measuring IC based on phase difference detection, measures the distance to a subject, and outputs obtained subject distance information to the main CPU 901.
Transfer to

E ² The PROM 913 is a non-volatile storage element, and the adjustment data for correcting an error generated due to a variation in the distance information or a functional variation in the lens position when converting the distance measurement data into the lens position data at the time of production is stored in the PROM 913. ^Two It is stored in the PROM 913.

The IFIC 911 measures the brightness of the subject,
The control of the driver 927 is performed. The light receiving element 912 measures the photometry of the copy body with the average and the spot, and
Supply to FIC911.

The driver 927 drives a DC motor, a stepping motor, a magnet, and the like. DC motor 9
Reference numeral 15 denotes a driving lens drive, DC motor 917 denotes zooming, and DC motor 919 denotes charging and mirror driving of a front curtain and a rear curtain of a focal plane shutter;
Feed the film. The stepping motor 921 drives the aperture, and the magnets 923 and 925 respectively lock the leading curtain and the leading curtain of the focal plane shutter.

A BIC 909 is a shake detection IC,
The infrared light emitted from D929 is reflected on the face of the photographer and received by two pairs of light receiving elements 931.
It is supplied to the CPU 901 via the IC 909. FIG.
FIG. 2 is a release flowchart of a camera incorporating the shake detection apparatus according to one embodiment of the present invention.

First, when the fur release R 1 SW 903 is pressed, the photographing lens is driven to the in-focus position obtained from the distance measurement information by the LDRIV subroutine (S20).
Next, it is determined whether or not the R2SW 905 is ON (S2
1) When the second release R2SW 905 is turned on, the mirror is raised in the MUDRIV subroutine (S22), and the aperture is driven to a predetermined aperture position in the AVCDRIV subroutine (S23). Here, in the shake detection subroutine BSEN (S24), the shake of the camera is detected, and when the shake is converged, the SDRI
The process moves to the V subroutine (S25), in which the focal plane shutter is driven to expose the film. Then A
In the VODRIV subroutine (S26), the aperture is returned to the original position (open position), and the MDDRIV subroutine (S2
7) The mirror is lowered, and the WIND subroutine (S2)
In step 8), the film is fed for one frame.

The shake detection subroutine BSEN24 will be described in more detail with reference to FIG.
929 is turned on (S30), and a timer is started (S31). Next, a limiter is determined (S32). If the shake amount does not converge even after a predetermined time has elapsed, a warning flag is set, the LED 929 is turned off (S35), and the process exits the subroutine. Also, when the shake in the limiter is equal to or less than the predetermined value (S34), the LED 929 is turned off and the process exits the subroutine. FIG. 24 shows a subroutine for detecting the shake amount in FIG.

The output from the BIC 909 is A / D converted to obtain an ADDT (S41). Next, INITFG is checked (S42). INITFG is a flag that is initialized to 0 at the beginning of a main routine (not shown), and is set when this subroutine "vibration amount detection" is executed once. In the case of the first time, INITFG is set (S46). For the second and subsequent times, the previous A / D conversion value A
The difference between DOD and the current A / D conversion value ADDT is a predetermined value AD.
It is determined whether it is less than TH (S43). If the value is equal to or less than a predetermined value, a flag OKFG indicating that the shake amount is an allowable amount
Is set (S45), and the process exits this subroutine. If the value is equal to or more than the predetermined value, the current A / D conversion value ADDT is stored (S
44), exit this subroutine. As described above, the shutter can be opened at the position where the blur amount is the minimum. Further, the shutter can be released by predicting the timing at which the blur becomes minimum based on the output of the blur sensor. This technology is disclosed in Japanese Patent Application
Since it is described in detail in -218672 and the like,
Detailed description is omitted here. Hereinafter, an example of mounting a blur sensor on a camera will be described.

FIG. 25 is a perspective view of a camera provided with a blur sensor. 800 is a camera body, 802 is a finder eyepiece, 804 is a blur sensor, 806 is a release button , and 810 is a photographing lens . The arrows of x, y, and z are virtual axes on the camera, and represent rotation axes when indicating the direction of blur. That is, the shake A 'around the x axis is a shake in the rotational direction, and the shake around the y and z axes is a shake in the rotational directions B' and C ', respectively. FIGS. 26A and 26B show two directions,
FIG. 3 is a layout diagram of a shake sensor when detecting shake around x and y axes. FIGS. 27 (a), (b) and (c) show one direction x,
FIG. 7 is a layout diagram of a shake sensor when detecting a shake about y or an oblique axis. FIGS. 28A and 28B show the positional relationship between the camera and the photographer based on the texture when the photographer holds the camera. FIG. 29 shows a state where the photographer holds the camera as viewed from the side.

This shake sensor detects a change in the relative position (angle) between the sensor mounting surface and the photographer's face, and it is desired that the light projecting portion is close to a stable plane. FIG.
(A) the Ki respectively to the viewfinder in the right eye, FIG. 28 (b)'ll in the left eye Iteiru. At this time, by placing the sensor almost directly under the viewfinder, the blur sensor 804 emits light to the cheek of the photographer, and satisfies the above condition. FIG. 29 shows the blur sensor 804 and the vertical position of the photographer. Therefore, the blur sensor 804 and the viewfinder eyepiece 8
02 is the position shown in FIG.
4 is arranged so as to be located almost directly below the finder eyepiece 802. Hereinafter, the arrangement of the light emitting and receiving units will be described with reference to FIGS.

FIG. 26 shows how to detect a shake in two axial directions.
(A) As shown in (b), the light receiving section is arranged in a direction perpendicular to the detection axis. For example, (a) detects shake around x and y axes, and (b) detects shake around two axes in oblique directions. When detecting the blur in one axis direction, by arranging as shown in FIGS. 27 (a), (b) and (c), the blur around the x, diagonal and y axis is detected. 2
The detection in the axial direction or the one-axis direction may be selected depending on the degree of accuracy or the direction in which the shake is to be detected.

Although the above description has been made with reference to the configuration of one light-emitting unit and two light-receiving units in FIG. 4, the application as shown in FIG. 30 is also conceivable. (A) is two light projections, two light receptions, (b) is two light projections,
This is an example of one light reception. In these cases, since there are two light emitting units, L ₁ and L ₂ are respectively illuminated in time series (− line and... Line in chronological order), and the current of the light receiving element is sampled and held. It can be easily achieved by connecting to.

[0059]

As described in detail above, the camera shake detecting apparatus of the present invention can detect blur even with the mirror up with a simple configuration.

[Brief description of the drawings]

FIG. 1 is a configuration diagram for performing tilt detection according to an embodiment of the present invention.

FIG. 2 is a diagram for describing a method for detecting camera shake.

FIG. 3 is a diagram showing a positional relationship between a subject and a tilt sensor.

FIG. 4 is a diagram showing a sensor configuration having two light receiving units for one light projecting unit.

FIG. 5 is a diagram illustrating a detailed configuration of a tilt detection circuit.

[6] FIG. 6 (a) is a diagram showing the magnitude of the difference output V _OS for the relationship between the V _OT1 and V _OT2, FIG. 6 (b) Figure 1
3 is a diagram illustrating a configuration of a subtraction circuit of FIG.

FIG. 7 is a diagram showing the minimum necessary functional blocks when the circuits in FIGS. 5 and 6 are converted to ic.

FIG. 8 is a diagram showing functional blocks in a case where a driving circuit for a light emitting unit (infrared LED) is further added to the function of FIG. 7;

9 is a diagram showing a state when ic of FIG. 8 is connected to a CPU.

FIG. 10 is a diagram illustrating a configuration of a tilt detection sensor.

FIG. 11 shows the inclination detection sensor of FIG. 10 and FIGS. 5 and 6
FIG. 6 is a diagram showing a tilt angle φ measured by using the shake detection circuit and a φ-V _OUT characteristic of an output V _OUT of the tilt detection circuit.

FIG. 12 shows a case where there is no lens in front of the light projecting section L and the light projecting angle is about ± 1.
It is a figure which shows a φ-V _OUT characteristic at about 5 degrees.

FIG. 13 is a diagram illustrating a configuration of a PSD transmitting unit, a two-dimensional PSD, and its vicinity.

FIG. 14 is a correlation diagram between the shake sensor and the y-axis of the camera shake signal when the reflection surface is a flat surface.

FIG. 15 is a diagram illustrating an experimental example for correlating a camera shake signal with a shake sensor.

FIG. 16 is a diagram showing a correlation between a PSD camera shake signal and a y-direction output (y-direction displacement change) of a shake sensor.

FIG. 17 is a diagram showing a correlation between a PSD camera shake signal and a derivative (y-direction speed change) of a y-direction output of a shake sensor.

FIG. 18 is a diagram showing a correlation between a PSD camera shake signal and a change in displacement of a shake sensor in the x direction.

FIG. 19 is a diagram showing a correlation between a PSD camera shake signal and a change in speed of the shake sensor in the x direction.

FIG. 20 is a diagram showing a circuit configuration of a detection circuit having a steady light removing function.

FIG. 21 is a block diagram of a TTL single-lens reflex camera incorporating a shake detection device according to one embodiment of the present invention.

FIG. 22 is a release flowchart of a camera incorporating the shake detection apparatus according to one embodiment of the present invention.

FIG. 23 is a diagram showing a procedure of a shake detection subroutine BSEN24.

FIG. 24 is a diagram illustrating a procedure of a shake amount detection subroutine in FIG. 23;

FIG. 25 is a perspective view of a camera provided with a blur sensor.

FIG. 26 is an arrangement diagram of a shake sensor when detecting shake around x and y axes in two directions.

FIG. 27 is an arrangement diagram of a shake sensor when detecting shake around an axis in one direction x, y or an oblique direction.

FIG. 28 is a diagram illustrating a positional relationship between the camera and the photographer based on the texture when the photographer holds the camera.

FIG. 29 is a diagram illustrating a state where the photographer holds the camera as viewed from the side.

FIG. 30 is a diagram illustrating another configuration example of the light projecting unit and the light receiving unit.

[Explanation of symbols]

1 ... Drive circuit, 3 ... 1 / (i ₁ ) ^1/2 Circuit, 5 ... 1 /
(I ₂ ) ^1/2 Circuit, 7: subtraction circuit, 9: subject.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masataka Ide 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside the Olympus Optical Industrial Co., Ltd. (72) Inventor Jun Maruyama 2-43-2 Hatagaya, Shibuya-ku, Tokyo Within Olympus Optical Co., Ltd. (72) Inventor Toshiro Kikuchi 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Co., Ltd. (56) References JP-A-4-151135 (JP, A) Hei 2-5 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03B 17/00 G03B 5/00

Claims (1)

(57) [Claims] 1. A light emitting and receiving device which is arranged on the back of a camera, emits light toward a photographer, receives reflected light from at least two points by a light receiving element, and outputs a photocurrent signal corresponding to each point. Means for calculating the difference between the reciprocals of the square root of the photocurrent output from the light-receiving element, wherein the output of the arithmetic means is used as a camera shake signal.