JPH10142649A - Blurring correcting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the fluctuation of light quantity by the individual dispersion of each of a projecting element and a position detecting element by providing a regulating part for regulating the relative positional relation in detecting optical axial direction of the position detecting element and the projecting element. SOLUTION: In order to regulate the position in detecting optical axial direction of a projecting part 23, a regulating part 40 using rack-and-pinion mechanism is provided. A CPU 3 makes a LED 23a emit a light, and the received light quantity by a position sensitive device(PSD) at that time is measured. When this light quantity is judged within an allowable difference, the regulation is terminated. On the other hand, when it is judged out of the allowable difference, it is judged whether the light quantity is larger than a designed value or not. The position of the LED 23a is regulated by the regulating part 40 according to this judgment. This work is repeated until the light quantity is regulated within the designed value ± the allowable difference, and when the light quantity is laid within the designed value ± allowable difference, the regulation is terminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blur correction device for correcting image blur caused by camera shake or the like in a camera or the like, and more particularly, to a blur correction device having an improved position detection unit for detecting the position of a blur correction optical system. It is.

[0002]

2. Description of the Related Art Conventionally, as a blur correction device of this type, a part of a photographing lens (hereinafter referred to as a blur correction lens) is used to correct a blur of an image caused by a vibration of a camera during photographing. Is known to move in a direction perpendicular to the direction.

FIG. 6 is a block diagram showing an example of a conventional blur correction device. Two angular velocity sensors 30a, 30
b denotes a sensor for detecting the vibration of the camera 1 and the lens 2. The outputs of the angular velocity sensors 30a and 30b are subjected to signal processing by the angular velocity
Input to PU3. The CPU 3 generates a control signal including movement target position information of the blur correction lens 10 based on the angular velocity signal from the angular velocity processing circuit 4, and the control signal is output to the voltage driver 5. Voltage driver 5
Are motors 14a, 14b so as to correct image blur.
By b, the blur correction lens 10 is driven in the xy directions in a plane orthogonal to the optical axis.

The position sensors 20a and 20b are sensors for detecting the position of the driven blur correction lens 10. The detection signals are processed by the position detection processing circuit 6 and then sent to the CPU 3 as current position information. Feedback will be given.

Next, the structure of the entire position detecting section including the position detecting sensors 20a and 20b will be described. FIG.
FIG. 10 is a detailed diagram illustrating a position detection unit of a shake correction device according to a conventional example. Note that the position detection sensors 20a and 20b are arranged separately in the x-axis direction and the y-axis direction, but have the same structure, and therefore only the position detection sensor 20a is shown in FIG.

The position sensor 20a (20b) is a one-dimensional PSD (Position Sensitive Device) 21a (21) which is a position detecting element provided at the bottom of the case body 28a.
b), the slit member 22a (22b) fixed to the lens frame 11 holding the blur correction lens 10, and the PSD 21a (21) with respect to the slit member 22a (22b).
b) is provided on the top plate 29a on the side opposite to that of b), and comprises an LED 23a (23b) which is a light emitting element of a point light source.
The light emitted from 3a (23b) is
a (22b) to reach the PSD 21a (21b). A motor 14 for driving the blur correction lens 10 is provided on the symmetrical side of the position sensors 20a and 20b with respect to the optical axis of the blur correction lens 10.
a, 14b (see FIG. 6) are attached.

FIG. 8 is a diagram showing an ideal PSD output. As shown in FIG. 8A, the PSD 21a (21
b) shows the position information of the moving light as two current values I1 and I
The light receiving position is obtained by calculating the output as 2 and calculating this. Therefore, the position of the light that reaches the one-dimensional PSD 21a (21b) moves according to the moved position of the shake correction lens 10, and the two output signals of the PSD 21a (21b) change. This output signal is processed by the detection position processing circuit 6, and the CPU 3 can detect the position of the blur correction lens 10 in the x and y directions. As shown in FIG. 8B, the PSD 21a (21b)
If the length of the effective light receiving surface in the detection direction is 2L1 [mm],
Ideally, a position detectable stroke extends from the center position in the detection direction of the PSD 21a (21b) to ± L1 [mm], and the PSD 21a (21b) can detect the position of light within this stroke.

[0008]

In the above-described conventional shake correcting device, the position of the shake correcting lens 10 is detected by the slits 22a and 22b integrated with the lens frame 11 of the shake correcting lens 10 by the LEDs 23a and 23b. And the slit light is transmitted to the one-dimensional PSD 21a,
This is performed by receiving light at 21b. In addition, one position detection unit is provided for each of the xy axes, and detects the position of the shake correction lens 10 in the xy plane.

In this position detecting section, PSDs 21a, 21
The sum of the output currents from b depends on the amount of light incident on the PSDs 21a and 21b. The sum of this output current is PS
I1 which is the sum of outputs I1 and I2 from D21a and 21b
+ I2, the LEDs 23a and 23b emit light,
The light amount incident on the SDs 21a and 21b.

Ideally, the amount of incident light of this LED should be constant in the position detection range (see FIG. 8), but when the amount of incident light changes, I1 + I2 obtained from the outputs of the PSDs 21a and 21b also change in the same manner. . Of course, I
The same applies to the fluctuation trends of I1, I2, and individual. This fluctuation in the light amount of the LED causes a considerably large error even in the actual position detection unit.

The position detection is performed by processing the PSD output signals I1 and I2.
The output range fluctuates in subsequent signal processing. This will be described with reference to FIGS.

FIG. 9 is a block diagram showing a process of processing a PSD output current signal. In FIG. 9, output currents I1 and I2 from PSD 21a are current-to-voltage converters (I / V
Converters 25a1 and 25a2, respectively.
1, V2. These voltages V1 and V2 are amplified by the amplifiers 26a1 and 26a2, and the voltages V1 'and V1'
Get 2 '. The voltages V1 'and V2' are digitally converted by the A / D converter 27a, and the position is calculated by the calculator 28a.

FIG. 10 is a diagram showing the voltages V1 'and V2' after amplification. The amplified voltages V1 'and V2' are I
/ V converted voltages V1 and V2 are converted to dynamic range D
[V] is gained by the gain set so that it can be used effectively. Signals V1 'and V2' after amplification
Is designed to be within the range of D1 to D2 [V] in FIG.

However, as described above, the output currents I1,
When there is a change in I2, not only the converted voltages V1 and V2, but also the output ranges of the amplified voltages V1 'and V2' change. When the output range of the amplified voltages V1 'and V2' fluctuates in a decreasing direction, the dynamic range D [V]
In contrast, the output range of the amplified voltages V1 'and V2' is
Become smaller. This reduces the resolution of position detection,
The position detection accuracy also decreases.

Conversely, if the output range of the amplified voltages V1 'and V2' fluctuates in the increasing direction, the amplified voltage V1 'and V2'
The output range of 1 'and V2' is the dynamic range D [V]
Will be exceeded. That is, the signal is saturated around D2 [V]. In particular, as in the latter case, the amplified voltage V1 ′
, V2 'are saturated, information necessary for position detection cannot be obtained, and the current lens position cannot be obtained.

An object of the present invention is to provide a blur correction device capable of eliminating fluctuations in the amount of light due to individual variations of the light projecting element and the position detecting element.

[0017]

In order to solve the above-mentioned problems, a first aspect of the present invention provides a blur correction optical system for correcting a blur of an image, and a driving unit for driving the blur correction optical system. 5, 14), a position detecting element (21) for detecting the position of light on the light receiving surface, and a light projecting element (23) for projecting light to the position detecting element. And a controller (40) for adjusting a relative positional relationship between the position detecting element and the light projecting element in the detection optical axis direction.

According to a second aspect of the present invention, there is provided a blur correction optical system (10) for correcting a blur of an image, a driving unit (5, 14) for driving the blur correction optical system, and a position of light on a light receiving surface. A position detecting element (21) for detection, a slit member (22) provided in the blur correction optical system, and a light projecting element (23) for projecting light to the position detecting element via the slit member; A position detecting unit (20) for detecting a position of the blur correction optical system; and an adjusting unit (40) for adjusting a relative positional relationship between the position detecting element and the light projecting element in a detection optical axis direction. I have.

The third aspect of the present invention is the first or second aspect.
Wherein the adjustment section is capable of adjusting the position in multiple stages.

According to a fourth aspect of the present invention, there is provided the first to third aspects.
In the blur correction device according to any one of the above, the adjustment unit has a unitized structure together with the position detection element and the light projection element of the position detection unit.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a detailed view illustrating a position detection portion of the shake correction apparatus according to the first embodiment. The parts performing the same functions as those of the above-described related art are denoted by the same reference numerals, and overlapping drawings and descriptions are appropriately omitted. In the first embodiment, an adjusting unit 40 using a rack and pinion mechanism is provided to adjust the position of the light projecting unit 23 in the detection optical axis direction. The adjusting unit 40
The slit member 22a and the PSD 21a shown in FIG. 7 are immovable as in the related art, and the distance between the PSD 21a and the LED 23a is adjusted by changing the position of the LED 23a.

The adjustment section 40 has a rack 41a formed on a holder 23-1a of an LED 23a movably provided on a top plate 29a, and teeth meshing with the rack 41a are cut in a circle so that the position is fixed. A pinion gear 42a, a motor 44a that rotates the pinion gear 42a forward and reverse through a transmission system 43a, a driver 45a that drives the motor 44a based on a drive signal from the CPU 3, and the like are provided. By rotating the rack 41a up and down, the rack 41a
The LED 23a integrated with the camera is moved up and down (see arrows)
Position can be adjusted. Note that, in the LED 23a, an upward direction is defined as an a direction.

FIG. 2 is a flowchart showing the adjustment operation of the shake correction apparatus according to the first embodiment. First, CP
U3 causes the LED 23a to emit light (S100), and measures the amount of received light I1 + I2 of the PSD 21a at that time (S100).
101). Next, it is determined whether or not this light amount is within the design value ± tolerance (S102). If it is determined that the light amount is within the tolerance, the adjustment ends.

On the other hand, when the CPU 3 determines in S102 that the light amount is not within the tolerance, it determines whether or not the light amount is larger than the design value (S103). From this determination, the position of the LED 23a is adjusted by the adjustment unit 40. That is, when the light amount is larger than the design value, the position of the LED 23a is raised so as to increase the distance between the LED 23a and the PSD 21a in order to prevent over-range (S
104). That is, the adjustment unit 40 controls the LED 23a
Is moved in the direction a. Conversely, when the light amount is smaller than the design value, the position of the LED 23a is lowered so as to increase the light amount so that the range can be used effectively (S105). That is, the LED 23a is moved in a direction opposite to the direction a.

This operation is repeated until the light quantity falls within the design value ± tolerance, and when the light quantity falls within the design value ± tolerance (S102), the adjustment is completed. in this way,
By adjusting the height of the LED 23a only once by using the adjusting unit 40 having the rack and pinion mechanism, the PSD 2 can be adjusted regardless of the individual variation of the LED 23a.
1a can be kept constant.

According to the first embodiment, the position of the LED can be adjusted by the adjusting unit in the position detecting unit in the shake correction apparatus. In the case of a large variation from the design value, it is possible to cope with a light amount fluctuation such as a position detection output signal being extremely small with respect to a dynamic range or exceeding an output range (range over). This light amount adjustment is performed only once by the adjustment unit when the shake correction apparatus according to the present embodiment is assembled.

Here, the adjusting section 40 will be described in more detail. The position of the shake correction lens 10 is detected by taking into consideration the light quantity obtained from a light emitting element (LED) serving as a light source, the output range of a position detecting element (PSD), and the like, and a processing circuit
To design. However, as described above, the light amount fluctuation of the LED is actually quite large, so that the light amount cannot be kept constant. If the light quantity fluctuates, the range will be over in the processing circuit 6 later.

The factors of the light quantity fluctuation are considered to be three points of individual difference of LED, type of LED, and temperature characteristic. In particular, each LED will have a different amount of light. It is generally said that the variation in the light amount of the LED is about 1/2 to 2 times the design value.

As a matter of course, the amount of light emission differs depending on the type of LED. In general, under a certain amount of light emission, the intensity is equal to the LED in the optical axis direction of the LED.
It is known that it is inversely proportional to the square of the relative distance between PSDs (26a) (FIG. 3). That is, the smaller the LED-PSD distance (26a), the higher the photocurrent received by the PSD. Therefore, the fluctuation of the light amount can be canceled by providing the adjusting unit 40 for adjusting the distance between the LED and the PSD in the optical axis direction.

The present invention is provided with a means for solving the light quantity fluctuation caused by the above factors. The present invention has an adjustment unit which can adjust the relative distance between the LED and the PSD, and performs this adjustment. This makes it possible to adjust the light emission amount. That is, if the distance between the LED and the PSD is made variable in accordance with the individual light amount of the LED and this distance is adjusted, a constant light amount can be maintained. Also, LE
If the members for fixing the D and PSD are integrated, it can be applied to other devices employing this position detection unit.

(Second Embodiment) FIG. 4 is a view showing a second embodiment of a blur correction device according to the present invention. In the second embodiment, the LED 23 a
There is provided an adjusting unit 50 for adjusting the height. The adjustment unit 50 includes a holder 51, a holding ring 54, a spring 57, and the like.

The holder 51 is provided with a top plate 29a (see FIG. 1).
, For accommodating the LED 23a, and a stepped hole 52 having a small diameter portion, a medium diameter portion, and a large diameter portion is formed. The stepped hole 52 has a screw portion 53 formed in a large diameter portion. The holding ring 54 is provided integrally with the LED 23 a, and a screw portion 55 screwed with the screw portion 53 of the holder portion 51 is formed on the outer periphery, and the holding ring 5 is formed on the upper surface.
A screw groove 56 for rotating the screw 4 is formed. The spring 57 is for urging the LED 23a upward in FIG. 4, and is inserted between the neck of the LED 23a and the middle diameter portion of the holder 51.

The adjusting section 50 of the present embodiment includes a holding ring 5
By rotating the screw groove 56 of No. 4, the holding ring 54
Is moved up and down, and the LED2
The vertical position of 3a can be adjusted.

(Third Embodiment) FIG. 5 is a view showing a third embodiment of a blur correction device according to the present invention. The adjustment unit 60 of the third embodiment includes a holder 61, a spring 63, and the like.
This is a structure in which the height of the LED 23a is adjusted by using the bending of the spring 63.

The holder 61 is provided with a top plate 29a (see FIG. 1).
, For accommodating the LED 23a, and having a structure in which the spring 63 is easily fitted.
Are formed at predetermined intervals in the vertical direction. Spring 6
3 is inserted into the spring hook groove 62, and the upper end is the LED 23a.
Is in contact with the neck.

The adjusting section 60 of the third embodiment performs the coarse positioning stepwise by inserting the spring 63 into one of the spring engaging grooves 62, and thereafter performs the light amount measurement similarly to the first embodiment. While performing, by the drive mechanism not shown,
The LED 23a can be accurately positioned by being pressed downward and making fine adjustments using the bending of the spring 63.

Various modifications and changes are possible without being limited to the above-described embodiment, and these are also within the equivalent scope of the present invention. For example, although an example in which the light projecting element such as an LED is positioned has been described, the positioning may be performed by moving a position detecting element such as a PSD. Further, the adjustment unit is not limited to the structure of each of the above-described embodiments, and may use a ratchet mechanism or the like.

[0038]

As described above, according to the present invention,
Since the distance between the light projecting element and the position detecting element is adjusted, it is possible to keep the light quantity fluctuation due to the individual variation of each element constant. In addition, if an adjusting unit for adjusting the distance between the light emitting element and the position detecting element is provided and each element is configured as a unit, it is possible to cope with a difference in light amount depending on the type of each element.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of a blur correction device according to the present invention.

FIG. 2 is a flowchart illustrating an adjustment operation of the shake correction apparatus according to the first embodiment.

FIG. 3 is a diagram showing a relationship between a distance between a light emitting element and a light receiving element and a light amount.

FIG. 4 is a diagram showing a second embodiment of the shake correction apparatus according to the present invention.

FIG. 5 is a diagram showing a third embodiment of the shake correction apparatus according to the present invention.

FIG. 6 is a block diagram illustrating an example of a conventional shake correction apparatus.

FIG. 7 is a detailed diagram illustrating a position detection unit of a shake correction device according to a conventional example.

FIG. 8 is a diagram showing an ideal PSD output.

FIG. 9 is a block diagram illustrating a process of processing a PSD output current signal.

FIG. 10 is a diagram illustrating voltages V1 ′ and V2 ′ after amplification.

[Explanation of symbols]

1: Camera body 2: Lens 3: CPU 4: Angular velocity processing circuit 5: Voltage driver 6: Position detection processing circuit 10: Blur correction lens 11: Blur correction lens frame 14a, 14b: Driving motor 20a, 20b: Position sensor 21a , 21b: Position detecting elements (PSD) 22a, 22b: Slit members 23a, 23b: LEDs 24a, 24b: LED-PSD distances 25a1, 25a2, 25b1, 25b2: Current-voltage converters 26a1, 26a2, 26b1, 26b2: Amplifier 27a, 27b: A / D converter 28a, 28b: Operation unit 30a, 30b: Angular velocity sensor 40: Adjustment unit 41a, 41b: Rack 42a, 42b: Pinion gear

Claims (4)

[Claims] 1. A blur correction optical system that corrects image blur, a drive unit that drives the blur correction optical system, a position detection element that detects a position of light on a light receiving surface, and light to the position detection element. A position detecting unit having a light projecting element for projecting light, and detecting a position of the shake correction optical system; and an adjusting unit for adjusting a relative positional relationship between the position detecting element and the light projecting element in a detection optical axis direction. A blur correction device comprising: 2. A blur correction optical system for correcting a blur of an image, a drive unit for driving the blur correction optical system, a position detection element for detecting a position of light on a light receiving surface, and provided in the blur correction optical system. A position detecting unit for detecting a position of the blur correction optical system, the light detecting element having a light projecting element for projecting light through the slit member and the position detecting element through the slit member; An image stabilization apparatus comprising: an adjustment unit that adjusts a relative positional relationship of an optical element in a detection optical axis direction. 3. The blur correction device according to claim 1, wherein the adjustment unit is capable of adjusting a position in multiple stages. 4. The blur correction device according to claim 1, wherein the adjusting unit is unitized together with the position detecting element and the light projecting element of the position detecting unit. An image stabilizing device characterized by the following.