JPH06130474A - Camera shake sensing device of camera and inclination sensing device - Google Patents

Abstract

PURPOSE:To provide controllability for the level shift amount to any desired value by a level shift circuit after a computation reversely proportional to the square root of the photo-current output for compatibly achieving the enhancement of the inclining angle sensing resolution and widening of the inclining angle sensing range. CONSTITUTION:A driver circuit 12 drives a light projecting element 11 to cast light to the photographer positioned on the back of a camera. Sensors 13, 14 receive the reflected light from the photographer. The first and second calculator circuits 15, 16 compute the photo-current generated by the sensors 13, 14 into the outputs inversely proportioned to their square roots and emit the results. A level shift circuit 17 passes the output from the second calculator circuit 16 to a differential amplifier circuit 18 upon subjecting to a level shift. The circuit 18 conducts a differential amplification upon receiving the output level shifted and the output of the first calculator circuit 15. A control circuit 19 decides the level shift amount of the level shift circuit 17 in accordance with this output which was differentially amplified.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tilt detecting device and a camera shaking detecting device for detecting a camera shake by detecting a relative tilt between a photographer and a camera body.

[0002]

2. Description of the Related Art Conventionally, various types of shake detection devices used in cameras and the like have been proposed. For example, Japanese Patent Application No. 4-149674 filed by the present applicant is arranged on the back surface of a camera, projects light toward a photographer, receives reflected light from at least two points by a light receiving element, and A light emitting / receiving means for outputting a corresponding photocurrent signal and a computing means for computing the difference of the reciprocal of the square root of the photocurrent output from the light receiving element are provided, and the output of the computing means is used as a shake signal. A characteristic camera shake detection device is disclosed. Regarding the technique disclosed in this Japanese Patent Application No. 4-149674, its configuration and action will be described below.

A method for detecting camera shake will be described with reference to FIG. 11. A tilt sensor 2 is arranged on the rear surface of the camera 1, and the tilt sensor 2 is separated from the rear surface of the camera 1 by a predetermined distance. It is assumed that there is a face 3. Assuming that the shooting start time is as shown in FIG. 11A and the face 3 is hardly moved during the shooting, the position of the camera 1 when a camera shake occurs
It can be expressed as shown in FIG. That is, when there is camera shake, the rotation center of the camera 1 moves by x, and the camera 1 (tilt sensor 2) tilts by θ.

FIG. 12 is a diagram showing the relationship between the inclination sensor 2 and the face 3. In FIG. 12, reference numeral 4 is a light projecting element, and 5 and 6 are sensors for receiving the reflected light from the light projecting element 4 and converting it into a current. Here, the sensor 5, the light projecting element 4, and the sensor 6 are arranged in a line in the vertical direction of the face 3.

FIG. 13 is a block diagram of an electric processing system. Reference numeral 7 is an arithmetic circuit for processing the photocurrent Ip ₁ from the sensor 5 to generate a voltage proportional to the value represented by the relational expression of the equation 1. Further, the arithmetic circuit 8 is for processing the photocurrent Ip ₂ from the sensor 6 in the same manner as the arithmetic circuit 7 to generate a voltage proportional to the value expressed by the relational expression of the mathematical expression 2.

[0006]

[Equation 1]

[0007]

[Equation 2] A driving circuit 9 drives the light projecting element 4. The differential amplifier 10 is for differentially amplifying the output voltages of the arithmetic circuits 7 and 8. Here, the differential amplifier 10
Is a voltage proportional to the value expressed by the relational expression of Equation 3, and this voltage is proportional to the inclination of the face with respect to the sensor surface.

[0008]

[Equation 3] That is, by obtaining the amount of change in the relational expression of Equation 3,
The amount of change in the tilt angle θ can be obtained.

[0009]

However, in such a conventional example, it is necessary to improve the accuracy of blur prevention,
That is, it is difficult to simultaneously improve the inclination angle detection resolution and secure a necessary inclination angle detection range. In order to increase the inclination angle detection resolution, the amplification factor A of the differential amplifier 10 needs to be increased, but since the power supply voltage of the circuit is limited, increasing the amplification factor A increases the inclination angle detection range. Becomes narrower.

This problem will be described with reference to FIGS. 14 and 15. As shown in FIG. 14A, when the face 3 is parallel to the sensor surface 2, the number 1 and the number 2
The change in the value expressed by the relational expression of
4 (b). Therefore, the output of the differential amplifier 10 becomes as shown in FIG.
A linear relationship is established in the range of −θ ₀ ≦ θ ≦ + θ ₀ , and the tilt angle can be detected. Here, the range of −θ ₀ ≦ θ ≦ + θ ₀ is a tilt angle corresponding to the blurring that occurs during one release operation.

On the other hand, consider the case where the face 3 is inclined at a large angle with respect to the sensor surface 2 as shown in FIG. When a cheek is used as the face 3, for example, the cheek is originally inclined largely depending on the person, and therefore, the cheek is as shown in FIG. In this case, the change in the value expressed by the relational expressions of the equations 1 and 2 with respect to the inclination angle θ is as shown in FIG. Therefore, the output of the differential amplifier 10 becomes as shown in FIG. 15C, and is not in a linear relationship in the range of −θ ₀ ≦ θ ≦ + θ ₀ , and is in a saturated state except for a part thereof. The angle θ cannot be detected correctly.

The present invention has been made in view of the above problems, and provides a tilt detection device and a camera shake detection device which can both improve the tilt angle detection resolution and widen the tilt angle detection range. The purpose is to do.

[0013]

SUMMARY OF THE INVENTION That is, according to the present invention, a light projecting means for projecting light toward an object to be detected and light transmitting means arranged so as to sandwich the light transmitting means, respectively, reflect light from the object to be detected. From the first and second photocurrents, which receive the light and generate the first and second photocurrents according to the amount of the received light, the first and second calculated values inversely proportional to the square root from the first and second photocurrents, respectively. And a first calculating means for outputting the calculating means.
And a differential amplifying means for differentially amplifying the output of the second calculated value and outputting the tilt information of the object to be detected, and a calculation path from the first light receiving means to the differential amplifying means, It is characterized by comprising level shift means for level shifting the output and control means for controlling the level shift amount of the level shift means based on the output of the differential amplifying means.

Further, according to the present invention, the light projecting means and the first and second light receiving means are arranged on the back surface of the camera, and from the temporal change of the relative inclination between the photographer and the camera body, It is characterized by detecting camera shake.

[0015]

According to the present invention, the first and second light receiving means projecting light from the light projecting means toward the object to be detected and arranged with the light transmitting means sandwiched between the object to be detected. The respective reflected lights are received, and first and second photocurrents are generated according to the amount of received light. Then, from the above-mentioned first and second photocurrents, first and second calculation values inversely proportional to the square root are calculated by the calculation means and output. The outputs of the first and second calculated values by the calculating means are differentially amplified by the differential amplifying means, and the tilt information of the detected object is output. Then, in the calculation path from the first light receiving means to the differential amplification means, the output is level-shifted by the level shift means, and the level shift is performed by the control means based on the output of the differential amplification means. The level shift amount of the means is controlled.

Further, the light projecting means, the first
Also, the second light receiving means is arranged, and the camera shake of the photographer is detected from the temporal change of the relative inclination between the photographer and the camera body.

[0017]

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

FIG. 1 is a block diagram showing the concept of the first embodiment of the present invention. In the figure, the light projecting element 11 is driven by the drive circuit 12,
It is arranged on the back of the camera and projects light toward the photographer. Further, the sensors 13 and 14 as the first and second light receiving elements are arranged so as to sandwich the light projecting element 11 and on the back surface of the camera, and reflected light from the light projecting element 11 reflected from the photographer. For receiving light.

The first and second arithmetic circuits 15 and 16 are
The outputs generated by the sensors 13 and 14 are calculated. The level shift circuit 17 level-shifts the output of the second arithmetic circuit 16 and supplies it to the differential amplifier circuit 18. The differential amplifier circuit 18 differentially amplifies the outputs of the first arithmetic circuit 15 and the level shift circuit 17 and outputs the amplified outputs to the control circuit 19. The control circuit 19 is a circuit for determining the level shift amount of the level shift circuit 17 according to the output of the differential amplifier circuit 18.

In such a structure, the light projecting element 11 is driven by the drive circuit 12 to project the light toward the photographer on the back surface of the camera. This light is reflected by the photographer and received by the sensors 13 and 14 as reflected light. Then, the photocurrents generated by these sensors 13 and 14 are calculated and generated in the first and second arithmetic circuits 15 and 16 to outputs which are inversely proportional to the square root of the photocurrent. Of these, the output of the second arithmetic circuit 16 is
The level is shifted in the level shift circuit 17. This level-shifted output and the first arithmetic circuit 15
Is output to the differential amplifier circuit 18 and differentially amplified. Then, the control circuit 19 determines the level shift amount of the level shift circuit 17 according to the differentially amplified output. Next, a second embodiment of the present invention will be described.

FIG. 2 is a block diagram showing the configuration of the second embodiment according to the present invention. In the figure, an analog processing circuit 20 and a microcomputer 21 for sequence control are connected. Further, the analog processing circuit 20 is connected with a light emitting element 22, sensors 23 and 24 for detecting blurring, that is, for detecting a tilt angle of the face, and a capacitor 25 for level shift described later. These light emitting element 22, sensors 23 and 24
Are all located on the back of the camera and the sensor 2
3 and 24 are arranged in a line so as to sandwich the light emitting element 22. On the other hand, the microcomputer 21 is connected to an aperture drive circuit 26, a mirror-up drive circuit 27, a front curtain drive circuit 28 and a rear curtain drive circuit 29.

In this embodiment, the present invention is applied to a single-lens reflex camera, which has a diaphragm in the taking lens. The shutter uses a focal plane shutter and has a front curtain and a rear curtain. Further, although not shown, the light from the taking lens is normally guided to the upper finder optical system by a mirror, but the light from the taking lens is switched to the shutter direction by raising the mirror during photographing.

FIG. 3 is a circuit diagram showing details of the inside of the analog processing circuit 20. In the figure, 30 is a current source for supplying a current value Iref. Furthermore, 31, 32, 3
3 is a diode, and 34 and 35 are transistors. Assuming that the potential on the anode side of the diode 31 is V ₁ ,
It becomes like the relational expression of Formula 4.

[0024]

[Equation 4] Here, k is the Boltzmann constant, T is the absolute temperature, q is the unit charge of electrons, and Is is the reverse saturation current of the diode (transistor).

Since photocurrents Ip ₁ and Ip ₂ flow through the emitters of the transistors 34 and 35, respectively, the emitter potentials V ₂ and V ₃ of the transistors are
The relational expressions of Formulas 5 and 6 are obtained, respectively.

[0026]

[Equation 5]

[0027]

[Equation 6] Further, 37 and 38 are buffer amplifiers, and if the respective outputs are V ₄ and V ₅ , the relational expression of Equation 7 is established.

[0028]

[Equation 7]

Further, 39, 40 are transistors, 41,
42 is a diode. When the collector currents of the transistors 39 and 40 are Ic ₁ and Ic ₂ , respectively, the relational expressions of the equations 8 and 9 hold.

[0030]

[Equation 8]

[0031]

[Equation 9] Here, from the relational expressions of the above equations 4, 5, 7, and 8,
The relational expression of Expression 10 is obtained.

[0032]

[Equation 10] Further, the relational expression of the expression 11 is obtained from the relational expressions of the expression 4, the expression 6, the expression 7, and the expression 9.

[0033]

[Equation 11] The resistance value of the resistors 43 and 44 is R, and therefore the potentials V ₆ and V ₇ of the collectors of the transistors 39 and 40 are obtained by the relational expressions of the equations 12 and 13.

[0034]

[Equation 12]

[0035]

[Equation 13] Further, when the output potential of the buffer amplifier 45 is V ₈ , the relational expression of Expression 14 is established.

[0036]

[Equation 14]

The buffer amplifier 46 has a level shift function, and a resistor 47 is connected to its feedback path. The current values from the current source 48 and the transistor 65 are added to the inverting terminal of the buffer amplifier 46. If these current values are 0, the relational expression of Expression 15 is established.

[0038]

[Equation 15]

The resistors 49, 50, 51 and 52 determine the rate of increase of the differential amplifier 53. The output of the differential amplifier 53 is output from the B1 terminal and the C1 terminal of the microcomputer 21 (see FIG. 2). C
One terminal is an A / D conversion input terminal. The output of the Vref generating circuit 55 is output from the B8 terminal and input from the C4 terminal of the microcomputer 21. This Vre
The f voltage is used as a reference voltage of the A / D converter in the microcomputer 21. That is, 0V to V
The analog voltage up to ref is A / D converted. Further, the output of the Vref generating circuit 55 is the resistance 5
The pressure is divided at 6,57. Here, the resistors 56 and 57 have the same resistance value, and the voltage at the midpoint thereof is Vref / 2.
This midpoint potential is input to one end of the resistor 52 after passing through the buffer amplifier 54.

Further, the above-mentioned resistors 49, 50, 51, 5
When the resistance values of 2 are R ₄₉ , R ₅₀ , R ₅₁ , and R ₅₂ , R ₄₉ = R ₅₀ , R ₅₁ = R ₅₂ , R ₅₁ = 100 · R ₄₉ . Therefore, the amplification factor A of the differential amplifier 53 is 10
It is 0. The output voltage V _OUT of the differential amplifier 53 is given by
It is calculated by the relational expression of.

[0041]

[Equation 16]

Further, the frame 58, the resistor 47, and the current source 3
Reference numerals 6 and 48 form a level shift circuit. B2,
The B3 terminals are C of the microcomputer 21, respectively.
It is connected to terminals 3 and C4, and inputs a cut (CUT) signal and a reset (RESET) signal from the microcomputer 21, respectively.

Further, 59 and 60 are transistors 61.
And 62 are base resistances, and 63 is a diode. An external capacitor 25 is connected to the B4 terminal. Further, 64 is a buffer amplifier, 65 is a transistor, and 66 is a resistor. Next, the operation of the level shift circuit thus configured will be described with reference to the timing chart of FIG.

At time t ₀ , the microcomputer 21 raises the reset signal to "H (high level)", the transistor 62 is turned on to start discharging the electric charge of the capacitor 25, and the cut signal is sent. Fall to "L" (low level). The microcomputer 21 causes the reset signal to fall to "L" at time t ₁ ,
Before this, the charging voltage Vc of the capacitor 25 is zero. Therefore, by lowering the reset signal to "L", the capacitor 25 is started to be charged by the current source 36, and Vc gradually starts to increase. As a result, the emitter potential of the transistor 65 connected to the buffer amplifier 64 starts to increase like Vc. The collector current I ₆₅ of the transistor 65 is obtained by the equation (17).

[0045]

[Equation 17] However, I ₃₆ is the output current value of the current source 36, t is the elapsed time from time t _1, C ₂₅ is the capacitance value of the capacitor 25, and R ₆₆ is the resistance value of the resistor 66. If the current value flowing out from the inverting terminal of the buffer amplifier 46 is I _OFFSET ,
The relational expression of is established.

[0046]

[Equation 18] However, I ₄₈ is the output current of the current source 48. Therefore, the offset voltage V _OFFSET of the buffer amplifier 46 is
It becomes like the relational expression of Expression 19.

[0047]

[Formula 19] However, R ₄₇ is the resistance value of the resistor 47.

Therefore, t <(I ₄₇ · C ₂₅ · R ₆₆ ) /
At I ₃₆ , V _OFFSET <0 and t> (I ₄₇ · C ₂₅ ·
With R ₆₆ ) / I ₃₆ , V _OFFSET > 0, and t = (I ₄₇ · C
_{For 25} · R ₆₆ ) / I ₃₆ , V _OFFSET = 0.

At t = 0, that is, at time t ₁ , V
_OFFSET = -R ₄₇ · I ₄₈ . When the object at the initial state is largely inclined, V _6, although a potential difference depending on the degree tilt between the V ₇ occurs, in V _OFFSET = -R ₄₇ · I ₄₈ to the potential difference is the time t ₁ R ₄₇ and I ₄₈ are set so as not to exceed the absolute value of.

Therefore, at time t ₁ , a large negative offset voltage is applied to the non-inverting terminal of the differential amplifier 53, so that the output voltage V ₀ of the differential amplifier 53 is as shown in FIG. , GND level.

At time t ₂ , V ₀ begins to rise and reaches V ₀ = Vref / 2 at time t ₃ . The microcomputer 21 monitors V ₀ from the C1 terminal,
_{When 0} = Vref / 2 is reached, the cut signal is raised to "H", and the output current from the current source 36 is cut off. As a result, the charging voltage Vc of the capacitor 25 is fixed. Next, the operation of the embodiment will be described with reference to the flowchart of FIG. Figure 5 shows the exposure flow with blur prevention applied.
It is a chart.

In the camera (not shown) in the same embodiment, the release SW (switch) is a two-stage stroke, and the first release SW is the first stroke SW.
Is turned on, and the second release is performed on the second stroke.
The switch SW is turned on. Then, in step S1,
The first release SW is monitored, and if the first release SW is on, the process proceeds to step S2 to perform AF (autofocus) processing. For more information about this AF,
Since it is not directly related to the present invention, its explanation is omitted.

Next, in step 3, the second release SW is monitored. If the second release SW is in the ON state, the process proceeds to step S4 to perform photometry, and then in step S5, automatic level adjustment is performed. In this automatic level adjustment, according to the timing chart shown in FIG.
The voltage of the capacitor 25 is set so that the level becomes ₀ = Vref / 2.

Then, in step S6, a signal is output to the diaphragm driving circuit 26 to start diaphragm driving.
Then, in step S7, a signal is output to the mirror-up drive circuit 27 to start the mirror-up. Subsequently, in step S8, diaphragm drive and mirror up detection are performed. The detection of the diaphragm drive and the end of mirror up are performed by detecting the state of an encoder (not shown). Next, in step S9, the amount of blurring is detected. The blur amount B (t) at the time t is calculated according to the relational expression of Expression 20.

[0055]

[Equation 20]

Here, V ₀ (t) is B1 at time t
It is the output voltage from the terminal. Also, V ₀ (t−Δt)
Is B1 at a time that is Δt before the time t.
It is the output voltage from the terminal.

When the amount of blur is detected in this way, the amount of blur is determined in the following step S10. Where B
If (t)> B _th (B _th is a constant), the shake amount is larger than the threshold value, and therefore the process returns to step S9 to repeat the shake amount detection. On the other hand, if B (t) ≦ B _th , the amount of blurring is smaller than the threshold value, so it is determined that the blurring is sufficiently small, and the process proceeds to step S11 to perform the front curtain start.

Next, in step S12, the exposure time timer is operated. Here, the exposure time timer is operated according to the photometric result obtained in step S4.
Then, in step S13, the trailing curtain is started and then returned. By operating in this way, it is possible to take a picture at the timing when the blur is small. Next, a third embodiment of the present invention will be described.

FIG. 6 shows a third embodiment of the present invention, which is shown in FIG.
3 is a circuit diagram showing an internal configuration of the analog processing circuit of FIG.
The configuration of the third embodiment is the same as that of the second embodiment except that the internal portion of the analog processing circuit is different from that of the second embodiment. Therefore, the circuit elements designated by the same reference numerals as those in the second embodiment have the same functions as those in the second embodiment, and the description thereof will be omitted here.

In the above-described second embodiment, the buffer amplifier 46 has the level shift function, but in the third embodiment, instead, the buffer amplifier 38 has the level shift function. There is. That is, the resistor 47 and the current source 48 connected to the buffer amplifier 46 are deleted, and the current source 6 is connected to the inverting terminal side of the buffer amplifier 38.
7 and a return path having a resistor 68 are connected. here,
When the offset voltage of the buffer amplifier 38 is set to V _OFFSET , the relational expression of Expression 21 is established.

[0061]

[Equation 21] Then, the relational expression of the expression 22 is obtained from the relational expressions of the expression 6 and the expression 9.

[0062]

[Equation 22] Further, the relational expression of Expression 23 is obtained from the relational expression of Expression 4.

[0063]

[Equation 23] Here, if V _OFFSET = (kT / q) lnI _OFFSET and the relational expression of the above equation 23 is modified, the relational expression of the following equation 24 is obtained.

[0064]

[Equation 24] Accordingly, by providing a function of the level shift to the buffer amplifier 38 is changed to V ₇ 'the output of the V ₇ is shown in the number 25 of the relation.

[0065]

[Equation 25] Therefore, comparing with the relational expression of the above equation 13, V ₇ ′ -VC
The coefficient is multiplied by I _OFFSET times with respect to C. As described above, the third embodiment differs from the above-described second embodiment in the level shift method, but the level adjustment can be roughly performed in this method as well.

FIG. 7 is a circuit configuration diagram showing a modification of the above-described third embodiment. In the third embodiment, the buffer amplifier for level shifting is provided after the transistor 35 for logarithmic compression, but in the modification shown in FIG. 7, the buffer amplifier 69 and the resistor 70 for level shifting are provided. Are provided in front of the transistor 35 for logarithmic compression. Incidentally, in FIG. 7, the circuit elements having the same reference numerals as those in FIG. 6 have the same functions.

Further, in the third embodiment, as shown in FIG. 11 or 12, only uniaxial shake detection is performed, but the arrangement as shown in FIG. 8 is adopted. Alternatively, the shake detection in the biaxial directions may be performed. That is, the light projecting element 4, the sensors 5 and 6 are the same as those shown in FIG. 12, and are one light emitting element and a pair of sensors. On the other hand, the sensors 71 and 72 are for detecting blurring in a direction orthogonal to the blurring direction detected by the light projecting element 4, the sensors 5 and 6. The processing circuits of the sensors 71 and 72 are exactly the same as the processing circuits of the sensors 5 and 6. Next, a fourth embodiment of the present invention will be described with reference to FIGS.

In the second and third embodiments described above, the A / D converter in the microcomputer 21 is used for level adjustment, but in the fourth embodiment, the analog is used. A comparator is provided in the processing circuit 20 to adjust the level.

In the circuit configuration diagram shown in FIG. 9, FIG.
Circuit elements with the same reference numerals as have the same function. In FIG. 9, inverters 73 and 74 are connected in series between the B3 terminal and the base resistor 60 of the transistor 62. Also, 75 and 76 are NAND gates, and 77 is a comparator. Next, the operation of the level shift circuit according to the fourth embodiment will be described with reference to the timing chart of FIG.

At time t ₀ , the microcomputer 21 raises the reset signal to "H" to turn on the transistor 62 and start discharging the capacitor 25. At the same time, in the set-reset flip-flop composed of the NAND gates 75 and 76, since the signal of "L" is inputted to the terminal represented by the relational expression of the equation 26,
After being set, the output represented by the relational expression of Expression 27 becomes "L".

[0071]

[Equation 26]

[0072]

[Equation 27]

As a result, the transistor 61 is turned off, and the current from the current source 36 flows toward the diode 63. However, since the transistor 62 is on at this time, the capacitor 25 is not charged.

Next, at time t ₁ , when the reset signal is lowered to "L", the capacitor 25 starts charging,
Vc starts to increase gradually. Then, as in the second embodiment described above, V ₀ is started to increase at the time t _2, the reach to the V ₀ = Vref / 2 at the time t _3.

As a result, the output of the comparator 77 is
Inversion from "H" to "L" resets the set-reset flip-flop, and the output represented by the relational expression of Expression 27 becomes "H". Therefore, the transistor 61 is turned on, and the output current from the current source 36 is cut off. As a result, the charging voltage of the capacitor 25 is fixed.

[0076]

As described above, according to the present invention, since the level shift circuit is newly provided, the tilt detection device capable of enhancing both the tilt angle detection resolution and the tilt angle detection range can be achieved. Also, it is possible to provide a camera shake detection device.

[Brief description of drawings]

FIG. 1 is a block diagram showing the concept of a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a second embodiment according to the present invention.

FIG. 3 is a circuit diagram showing details of the inside of the analog processing circuit of FIG.

FIG. 4 is a timing chart for explaining the operation of the level shift circuit according to the second embodiment.

FIG. 5 is a flowchart of exposure to which blurring prevention is applied, for explaining the operation of the second embodiment.

FIG. 6 is a circuit diagram showing an internal configuration of the analog processing circuit of FIG. 2 in a third embodiment of the present invention.

FIG. 7 is a circuit configuration diagram showing a modification of the third embodiment.

FIG. 8 is a diagram showing an arrangement example of a light projecting element and a sensor when performing blur detection in two axial directions.

FIG. 9 is a circuit diagram showing an internal configuration of the analog processing circuit of FIG. 2 in a fourth embodiment of the present invention.

FIG. 10 is a timing chart illustrating the operation of the level shift circuit according to the fourth embodiment.

FIG. 11 is a diagram showing how a camera shake is caused by a conventional camera shake detection device.

FIG. 12 is a diagram showing a relationship between the tilt sensor of FIG. 11 and a face.

FIG. 13 is a schematic block configuration diagram showing a circuit of an electric processing system of a conventional camera shake detection device.

FIG. 14 is a diagram showing changes with respect to the tilt angle θ when the tilt sensor and the face are parallel to each other.

FIG. 15 is a diagram showing a change with respect to the tilt angle θ when the tilt sensor and the face are tilted at a large angle.

[Explanation of symbols]

11 ... Projecting element, 12 ... Driving circuit, 13, 14, 23,
24 ... Sensor, 15 ... First arithmetic circuit, 16 ... Second arithmetic circuit, 17 ... Level shift circuit, 18 ... Differential amplifier circuit, 19 ... Control circuit, 20 ... Analog processing circuit, 21 ...
Microcomputer, 22 ... Light emitting element, 25 ... Capacitor, 26 ... Aperture drive circuit, 27 ... Mirror up drive circuit, 28 ... Front curtain drive circuit, 29 ... Rear curtain drive circuit.

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] May 21, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0041

[Correction method] Change

[Correction content]

[0041]

[Equation 16] The frame 58, the resistor 47, and the current sources 36 and 48 are
It constitutes a level shift circuit. B2 and B3 terminals are
They are connected to the C 2 and C 3 terminals of the microcomputer 21, respectively, and are for inputting a cut (CUT) signal and a reset (RESET) signal from the microcomputer 21, respectively.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0046

[Correction method] Change

[Correction content]

[0046]

[Equation 18] However, I ₄₈ is the output current of the current source 48. Therefore, the offset voltage V of the buffer amplifier 46 is
_OFFSET is represented by the relational expression of Expression 19.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0047

[Correction method] Change

[Correction content]

[0047]

[Formula 19] However, R ₄₇ is the resistance value of the resistor 47.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0048

[Correction method] Change

[Correction content]

Therefore, t <(I ₄₈ · C ₂₅ · R ₆₆ ) /
At I ₃₆ , V _OFFSET <0 and t> (I ₄₈ · C ₂₅ ·
With R ₆₆ ) / I ₃₆ , V _OFFSET > 0, and t = (I ₄₈ · C
_{For 25} · R ₆₆ ) / I ₃₆ , V _OFFSET = 0.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0065

[Correction method] Change

[Correction content]

[0065]

[Equation 25] Therefore, comparing with the relational expression of the above expression 13, V ₇ −VCC
On the other hand, V ₇ ′ -VCC is multiplied by a factor of (I _OFFSET ) ^1/2 . As described above, the third embodiment differs from the above-described second embodiment in the level shift method, but the level adjustment can be roughly performed in this method as well.

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0067

[Correction method] Change

[Correction content]

Further, in the first to third embodiments,
As shown in FIG. 11 or 12, only uniaxial blurring detection is performed, but biaxial blurring detection may be performed with the arrangement shown in FIG. 8. That is, the light projecting element 4, the sensors 5 and 6 are the same as those shown in FIG. 12, and are one light emitting element and a pair of sensors. On the other hand, the sensors 71 and 72 are for detecting blurring in a direction orthogonal to the blurring direction detected by the light projecting element 4, the sensors 5 and 6. The processing circuits of the sensors 71 and 72 are exactly the same as the processing circuits of the sensors 5 and 6. Next, a fourth embodiment of the present invention will be described with reference to FIGS.

Claims (2)

[Claims] 1. A light projecting means for projecting light toward an object to be detected, and light-transmitting means sandwiching the light-transmitting means. First and second light receiving means for generating first and second photocurrents, and computing means for outputting first and second computed values inversely proportional to the square root from the first and second photocurrents, respectively Differential amplification means for differentially amplifying the outputs of the first and second calculation values by means, and outputting inclination information of the object to be detected; and a calculation path from the first light receiving means to the differential amplification means. In particular, the inclination detection is provided with a level shift means for level shifting the output, and a control means for controlling the level shift amount of the level shift means based on the output of the differential amplifying means. apparatus. 2. The light projecting means and the first and second light receiving means are arranged on the back surface of the camera, and the camera shake of the photographer is detected from the temporal change of the relative inclination between the photographer and the camera body. The camera shake detection device for a camera according to claim 1, wherein: