JP3253828B2 - Optical system adjustment device for image reader - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical system adjusting device for an image reading apparatus used in a digital copying machine, a facsimile machine, and the like, and more particularly, to moving a lens block having a lens and a photoelectric conversion element for adjusting the optical system. The present invention relates to an optical system adjustment device capable of preventing the floating when the operation is performed.

[0002]

2. Description of the Related Art As shown in the conventional example of FIG. 7, in an image reading apparatus used in a digital copying machine, a facsimile machine, or the like, reflected light emitted from a light source 38 and reflected on the original surface of an original S is reflected by a mirror 39 and a mirror 39. An image on a document surface is read by allowing the light to enter a photoelectric conversion element (for example, a CCD) 33 via a lens 32. In order to adjust the magnification in the image reading as described above, for example, as shown in Japanese Patent Application Laid-Open No. 2-20847, a method in which a table on which a lens 32 is attached is moved along a guide rod by a motor is adopted. Have been. In a reading apparatus employing this method, an optical system adjusting means including a table, a guide rod, a motor, and the like is permanently provided in the image reading apparatus, and has an enlargement / reduction (magnification) function.

However, in a facsimile machine, a low-cost copying machine, or the like, in which only the same-size function is provided, the permanent provision of the above-described optical system adjusting means in the image reading apparatus increases the cost. In addition, since there is no need for permanent installation at the same time, in such low-cost equipment, the optical system adjusting device is provided as a kind of equipment outside the image reading device. In other words, when adjusting the optical system for adjusting the magnification or the like in such an image reading apparatus, a lens block including a lens and a photoelectric conversion element is mounted on a base in the apparatus, and the optical system is externally controlled. The lens block in the device is gripped by the grip portion by inserting the grip portion of the adjustment device into the image reading device,
In this state, the gripper is moved, and the lens block on the base is slid thereby to adjust the magnification and the like, and then the lens block is fixed to the base.

[0004]

However, in the prior art in which the optical system adjusting device is not always provided in the image reading device as described above, the lens block is slid on the base during adjustment, so that friction with the base is caused. The lens block may be lifted by the resistance, so that the optical axis is deviated, and the output signal of the photoelectric conversion element read for adjustment greatly fluctuates. As a result, stable adjustment cannot be performed.

[0005]

An object of the present invention is to solve the above-mentioned problems of the prior art, and to prevent a lens block from floating during adjustment in an optical system adjusting device that is not permanently installed in an image reading apparatus, thereby achieving stable adjustment. It is an object of the present invention to provide an optical system adjustment device for an image reading device.

[0006]

In order to achieve the above object,
Optical adjustment device of the image reading apparatus of the present invention is an optical system adjusting device for adjusting the position of the lens block of an image reading apparatus including a lens block including a photoelectric conversion element and a lens reading a document image, wherein In a device arranged outside the image reading device, the optical system adjusting device is provided.
The lens holder is inserted into the image reading device and the lens
A gripper for gripping the lock, and moving the gripper.
And the lens block in the image reading device
Control to adjust the magnification by sliding in the optical axis direction on the base
Unit and the control unit slides the lens block.
The lens block is on the base due to the frictional resistance of
Raise the lens block from the top to the base
A lens block biasing section that elastically biases and prevents
It has the above configuration . Further, the image reading apparatus of the present invention
Optics adjusting device, the lens block urging unit, the <br/> lens block in contact with the the partial lens block sliding
And has a rotating member that rotates in the moving direction.
You .

[0007]

With the above arrangement, the first means includes:
When the lens block is lifted from the base when holding the lens block and moving on the base, the lens block is immediately pressed down from above by the lens block urging part. In this case, the output signal of the photoelectric conversion element, which is read at the same time, fluctuates greatly, and as a result, a problem that stable adjustment cannot be performed can be solved. In the second means, it is possible to reduce the time of insertion of lifting and gripping portion of the lens block, the impact caused by colliding the end and lens block of the lens block biasing portion.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below in detail with reference to the drawings. As shown in FIG. 7, the image reading apparatus to be adjusted by the optical system adjusting device converts reflected light of light emitted from the light source 38 and reflected on the original surface of the original S through the mirror 39 and the lens 32. An image is read from the document surface by being incident on the conversion element 33. As shown in the schematic diagram of FIG. 3, the optical system adjusting device 1 is placed outside the image reading device 30, the grip portion 2 is inserted into the image reading device 30, and the lens 32 and the photoelectric The lens block 31 containing the conversion element 33 is gripped, and is slid on the base 35 so as to be positioned at an optimum position.

FIG. 4 is an explanatory diagram schematically showing a main part of the image reading apparatus. FIG. 4 shows an arrangement in which an adjustment pattern P having a length L is arranged on a document surface, and an image thereof is read into a photoelectric conversion element 33 as an image having a length l via a lens 32 in a lens block 31. It shows that. The photoelectric conversion element 33 is provided on the substrate 36. Also,
The lens block 31 has an elongated hole 37, and has a structure that can be fixed to the base 35 through the elongated hole 37 after adjusting the movement along the optical axis Q.

FIG. 5 is an explanatory diagram for explaining the principle of adjusting the magnification by moving the lens block 31. As shown in FIG. FIG.
(A) shows that the lens block 31 is at a distance Z for a predetermined magnification.
Since it is shifted to the left by (Z> 0), it indicates that it is necessary to move to the position of the dotted line to the right. (B) indicates that the lens block 31 is shifted to the right by the distance Z, and It indicates that it is necessary to move to the left to the position. The shift amount Z is represented by L as a reference length of the pattern P, an imaging length corresponding thereto, that is, a reference length expressed as the number of pixels of the image of the photoelectric conversion element 33, and an imaging length at the time of shift. Assuming that l1, it can be obtained by the following equation.

Z = (1 / m) {(l / l1) −1} × f (m + 1) (1) m = (l × p) / L where f is the focal length of the lens, and m is used The magnification p is the pixel pitch of the photoelectric conversion element (CCD) 33. That is, the lens block 31 is moved to the document side (to the right in FIG. 5) when the calculation result by this formula is positive, and is moved in the opposite direction when the calculation result is negative. Hereinafter, an embodiment of the present invention for realizing such a movement will be described.

FIG. 1A is a side view of a main part of an optical system adjusting device according to an embodiment of the present invention, and FIG. 1B is a front view showing a state where a lens block 31 is gripped. As shown, the optical system adjustment device of this embodiment includes a lens block 31.
, A lens block urging unit 3 for preventing the lens block 31 from lifting, a support member 4 for supporting the grip unit 2 and the lens block urging unit 3, and a connection for connecting the support member 4 to the slider 5. Ball screw 8 for moving the slider 5 and the connecting member 6 in the direction of the arrow along the slide guide 7 using the member 6 and the pulse motor 9 as driving sources.
It has.

FIG. 1B is a front view of the lens block 31 and the main part of the optical system adjustment device viewed from the light source side (original side). As shown in FIG.
Are gripping both sides. For example, the grip portion 2 is formed of an elastic body or the like, and grips the lens block 31 from the left and right by a frictional force. However, when the lens block 31 is moved for adjustment, that is, when the lens block 31 is moved by being gripped by the grip portion 2, When the lens block 31 is going to jump upward due to, for example, being caught, it is gently gripped to allow instantaneous lifting, thereby reducing the impact force applied to the lens block 31.

Further, the lens block urging portion 3 includes a support portion 4
Are rotatably supported by stepped screws 11 on both sides (FIG. 1B) of the elastic body 12 (for example, a tension coil spring).
One end of the lens block urging portion 3 presses the lens block 31 from above with the constant pressure of the spring of 12a). Note that the elastic body 12 for applying a constant pressure is the above-described tension coil spring 12.
a has one end on the support member 4 and the other end on the lens block urging portion 3.
Is connected to one end by a spring hook 13,
A leaf spring may be used instead of the coil spring 12a .
The urging portion 3 may be made of an elastic body and attached to the support member 4 so as not to rotate, and may be pressed by the elastic force of the elastic body itself. However, a coil spring is preferable in terms of durability.

The lens block of the lens block urging unit 3
The rotating member 14 is rotatably provided at the end on the side that presses the 31. This rotating member 14 is a lens block 31
The contact moves when the gripper 2 moves down from above to grip the lens block 31 and the end (contact) of the lens block urging portion 3 hits the lens block 31. Rolling friction is used for the back-and-forth movement, thereby reducing the load.

FIG. 2 is a block diagram showing the configuration of a control system of an optical system adjusting apparatus according to an embodiment of the present invention, and FIG. 6 is an operation flowchart of the above embodiment. In FIG. 2, only the photoelectric conversion element 33 belongs to the image reading device. Hereinafter, the operation at the time of the operation for adjusting the lens block position will be described with reference to FIGS. First, the grip 2 of the optical system adjusting device is inserted into the image reading device, and the lens block 31 is gripped by the grip 2 (S1). At this time, the rotating member 14 of the lens block urging unit 3 is moved from above to the lens block.
The upper surface of 31 is pressed down. The photoelectric conversion element 33 in the image reading device and the control system of the optical system adjusting device are connected as shown in FIG. 2 (S2).

After the preparation as described above, the document is started to be conveyed by turning on the start key of the image reading apparatus (S).
3) A start signal from the start key or the like is also supplied to the control unit 21 (not shown), a drive ON / OFF signal from the control unit 21 is turned on, and a CCD driver unit having a timing generation unit is provided. 22 to photoelectric conversion element (C
CD) 33 are output.

Thus, the VIDEO is output from the photoelectric conversion element 33.
As the O signal, an analog signal corresponding to the density on the document surface is output for each line. This analog signal is CCD
The signal is amplified by the output amplifier 23 and input to the AD converter 24. A timing signal from the CCD driver unit 22 is also supplied to the AD conversion unit 24, and an analog signal is sampled in pixel units in synchronization with readout from the photoelectric conversion element 33, and is converted into, for example, 8-bit digital pixel data. Output. Further, the pixel data output from the AD conversion unit 24 is stored in the image data memory unit 25 via the bus switching unit 26.

When a predetermined number of lines have been read and the adjustment pattern P on the document has been read, the control unit 21 turns on / off the drive.
The F signal is turned off to stop the image reading.
Then, the control unit 21 performs a binarization process on the pixel data in the image data memory unit 25, and stores the binarized data in another area of the image data memory unit 25. Note that this binarization processing can also be performed by the AD conversion unit 25. In this case, 2
The binarized pixel data is output from the AD converter 25 and
The digitized data is directly stored in the image data memory unit 25 (S4).

In the binarized data, the adjustment pattern portion on the document is "1", and the background portion is "0" otherwise. Therefore, if the bar-shaped adjustment pattern is made parallel to the line direction (main scanning direction, that is, the direction in which the photoelectric conversion elements are arranged), the image of the adjustment pattern has a pixel data string in which “1” s are continuous. Subsequently, the control unit 21 reads the binarized data from the image data memory unit 25, and can easily recognize the number of continuous pixels corresponding to the length of the imaging pattern (S5).

When the control unit 21 recognizes the length (number of pixels) l1 of the read image, it compares it with the reference length l (S
6). That is, the shift amount Z is calculated from Expression (1). Alternatively, the shift amount Z corresponding to l1 is obtained from a table provided in the control unit 21. Subsequently, the control circuit 27 determines the moving direction and the moving amount of the lens block 31 according to the sign and the value of the deviation amount Z, gives a pulse train of a number proportional to the moving amount to the pulse motor 9, and Rotate by the required number in the corresponding direction.

Thus, the connecting member 6 and the slider 5 shown in FIG. 1A move in the direction of the arrow along the slide guide 7 (S7). Then, the support member 4 moves in the left-right direction (FIG. 1).
(A)), the gripper 2 moves in the left-right direction with the movement, and the lens block 31 moves on the base 35 in the arrow direction (left-right direction). During this movement, the lens block 31 may come up momentarily .
It is pressed from above by the part 3 and immediately returns to the original state.

After moving the lens block 31 as described above, the original is conveyed again (S3), and the control unit 21 obtains the image length l2 after the movement (S3).
5). If l2 is the same as the reference length l, the adjustment is completed (S8). On the other hand, if an error remains, the position adjustment of the lens block 31 corresponding to the error is similarly performed, and the adjustment is terminated when the error disappears (S
8). When the adjustment is completed, the lens block 31 is
(S9), and the adjustment work is completed by separating the gripper 2 and the like of the optical system adjustment device from the image reading device (S1).
0).

[0024]

As described above, according to the present invention,
First, as soon as the lens block tries to rise from the base during the movement, the lens block is pressed from above by the lens block urging portion, so that the fluctuation of the output signal of the photoelectric conversion element due to the optical axis shift is reduced, and the stability is reduced. Adjustment can be realized. Second, upon insertion of the lifting or gripping portion of the lens block, since the impact can be reduced by colliding with the end portion and the lens block in the lens block urging portion, it is possible to realize a more stable adjustment, Damage to the lens block urging portion and the lens block can be prevented.

[Brief description of the drawings]

FIGS. 1A and 1B are a side view and a front view of a main part of an optical system adjusting device according to an embodiment of the present invention.

FIG. 2 is a configuration block diagram of a control system of the optical system adjustment device according to the embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a relationship between an optical system adjustment device and an image reading device according to the present invention.

FIG. 4 is an explanatory diagram for explaining an optical system adjusting device according to one embodiment of the present invention.

FIGS. 5A and 5B are other explanatory views illustrating an optical system adjusting device according to an embodiment of the present invention.

FIG. 6 is an operation flowchart of the optical system adjusting apparatus according to the embodiment of the present invention.

FIG. 7 is an explanatory diagram of a main part of an image reading apparatus according to the related art and the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Optical system adjustment device, 2 ... Grasping part, 3 ... Lens block
Urging part , 4 ... support member, 11 ... stepped screw, 12 ... elastic body,
14 ... Rotating member, 21 ... Control unit, 30 ... Image reading device, 31 ...
Lens block.

Claims (2)

(57) [Claims] 1. A optical adjustment device for adjusting the position of the lens block of an image reading apparatus including a lens block including a photoelectric conversion element and a lens reading a document image, is disposed outside of the image reading apparatus Wherein the optical system adjustment device is inserted into the image reading device.
A gripper for gripping the lens block,
The lens block is moved to the
Slide in the optical axis direction on the base in the image reading device to enlarge the magnification
A control unit for adjusting the lens block, and the control unit controls the lens block.
Lens block due to frictional resistance when sliding the lens block
The lens block is raised from above the base.
A lens block that elastically biases the upper surface in the base direction to prevent it
An optical system adjusting device for an image reading device, comprising: 2. The lens block urging portion , wherein the lens block slides on a portion in contact with the lens block.
2. An optical system adjusting device for an image reading apparatus according to claim 1, further comprising a rotating member which rotates in a predetermined direction .