JPH0476454B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a filter conversion device for color-separating an optical image, and more particularly, to a filter conversion device for color-separating an optical image. Concerning switching to filters.

[Prior Art] An image reading device such as a so-called image scanner, which optically scans the surface of a document and reads optical images of figures, characters, etc. on the surface of the document as electrical signals, generally uses an optical system that is illuminated by an illumination optical system. The configuration is such that the reflected light from the document surface is imaged on a light receiving element such as a CCD sensor via a reduction optical system, thereby converting the optical image of the document surface into an image signal.

In addition, so-called color image reading devices that read originals in color focus the reflected light from the original surface on a light-receiving element through a filter corresponding to a specific hue, thereby creating an optical image of the original surface in color. It is separated and converted into image signals for each hue.

In other words, the color image reading device is configured to switch filters of the three primary colors Red R, Green G, and Blue B on the optical path of the light reflected from the document surface to obtain image signals corresponding to each hue. The original color original image can be reproduced from these hue-specific image signals. In addition,
In general, it is configured to be able to switch to an ND filter in addition to the three primary colors mentioned above, thereby obtaining an image signal effective for optical length alignment and light intensity adjustment.

There are various types (mechanisms) of filter conversion devices that switch these filters on the optical path. For example, a large number of circular holes are provided in a rotating disk so as to equally divide a predetermined concentric circle within the surface of the rotating disk, a circular filter is mixed in the holes, and the rotating disk is aligned with the optical path. There is a configuration in which they are arranged orthogonally and the optical path is cut by a circular filter on a rotating disk.

[Problems to be Solved by the Invention] However, the recent trend in color image reading devices is toward miniaturization, and as a result, filter conversion devices are also required to be more compact. ing.

In other words, with the rotating disk described above,
Since it requires a height equivalent to the diameter of the disc, there is a problem in that it is difficult to achieve miniaturization.

[Objective of the Invention] The present invention has been made in view of the above background, and provides a compact filter conversion device that does not hinder miniaturization of various image processing devices that require a filter conversion operation. is its purpose.

[Means for Solving the Problems] Therefore, in the filter conversion device according to the present invention, a plurality of filters are held in a row, and a drive groove that is orthogonal to the filter arrangement direction and open to at least one side is arranged in the filter arrangement direction in the filter arrangement direction. A filter holding means formed with a plurality of conditions at predetermined intervals sandwiching the filter; a guide means for guiding the movement of the filter holding means in the filter arrangement direction; A rotating member that is rotatably provided to substantially coincide with an extension line, and a drive groove that protrudes from the rotational plane of the rotating member at intervals equal to the drive groove interval of the filter holding means across the center of rotation of the rotating member. and a driving means for rotationally driving the rotating member, and when the rotating member is rotated by the driving means, the two driving members are alternately fitted into the driving groove of the filter holding means and rotated. As the member rotates, the fitting position thereof moves along the drive groove, and the filter holding means is moved and driven along the guide means, so that a filter of a desired hue can be positioned between the optical paths.

With the above configuration, the large number of filters (filter group) are held in a row, so the height can be reduced. Therefore, by applying this, various image processing devices can be miniaturized.

[Embodiments of the Invention] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a side sectional view schematically showing the main components of a color image reading device to which an embodiment of a filter conversion device according to the present invention is applied.

This color image reading device U reads an original PA placed on a transparent plate 1 in color.
A fluorescent lamp 2 illuminates the original surface 0, and the reflected light from the original surface 0 is reflected by a plurality of mirrors 3, 4, 5, 6,
7 and guided to a reduction lens 8 via a filter conversion device F according to the present invention, and is imaged on a CCD sensor 9 disposed at the focal position of the reduction lens 8, so that an optical image of the original PA is formed. is converted into an image signal by the CCD sensor 9.

FIG. 2 is a plan view of the color image reading device shown in FIG. 1. FIG. 3 is a plan view of the main parts of the filter conversion device F, with a part of FIG. 2 viewed from the - arrow.

The filter conversion device F includes filters R, G, and B for the three primary colors of red, green, and blue whose color separation hues are different from each other, and a neutral density filter for obtaining an image signal effective for optical length alignment and light intensity adjustment. This is a filter switching device that appropriately sets the ND on the optical path of the reflected light from the document surface 0.

In other words, this filter conversion device F includes a holding plate 10 as a filter holding means for holding the filter group (filters ND, R, G, B) in a line;
Guide rails 11 and 12 serve as guide means for guiding the holding plate 10 in the column direction of the filter group.
It is equipped with a driving disk 13 as a rotating member and a driving motor 14 as a driving means for rotationally driving the driving disk 13, and guide rails 11, 12.
The drive disk 13 is fixed and pivotally supported at a predetermined location within the device by a support member (not shown).

The drive motor 14 is driven and controlled based on detection signals from reflective photo sensors 15 and 16 that detect the movement of the holding plate 10 and a reflective photo sensor 17 that detects the rotational position of the drive disc 13. The control will be described later with reference to a circuit diagram.

The light receiving range of the CCD sensor 9 is a substantially rectangular range X shown in FIG. has been done.

The holding plate 10 has a plurality of substantially rectangular openings 10b formed in its longitudinal direction, and the filter group is fixed to each of the openings 10b. Furthermore, a plurality of long grooves 10a are formed between these openings 10b as driving grooves perpendicular to the row direction.
A pin 13a serving as a driving member provided upright on a driving disk 13, which will be described later, is fitted into and engaged with the long groove 10a.

The holding plate 10 is slidably held by guide rails 11 and 12 each having a substantially U-shaped cross section at the top and bottom of the longitudinal direction. 12 is supported by a support member (not shown) and fixed to the front side of the reduction lens 8, that is, at a predetermined position between the mirror 7 and the reduction lens 8.

The driving disk 13 has a pair of pins 13a, 13a facing each other on a predetermined circumference within its plane, and
Slits 13b, 13b are formed opposite to each other on the circumferential edge portion perpendicular to the pins 13a, 13a, and the pins 13a, 13a are connected to the aforementioned holding plate 1.
It is slidably fitted into and engaged with the long groove 10a of 0. The drive disk 13 is rotatably supported by a support member (not shown) and connected to a drive motor 14 by a gear train having a predetermined reduction ratio. Further, the pins 13a are configured such that their opposing pitches are the same pitch as the pitch between the long grooves 10a.

Therefore, when the drive motor 14 rotates the drive disk 13 by half a rotation, the long groove 10a engaged with the pin 13a erected on the drive disk 13 slides in conjunction with the rotation. In other words, the driving disk 13
are the pins 13a, 13 that are erected facing each other in that plane.
The pins 13a are configured to be stopped in a state where they are simultaneously engaged with two of the plurality of long grooves 10a formed at a predetermined pitch on the holding plate 10, and the pins 13a, 13a As the pin 13a rotates, one pin 13a is disengaged from the corresponding long groove 10a, and the other pin 13a is rotated while being engaged with the other corresponding long groove 10a. The holding plate 10 is moved by the engagement relationship with the corresponding long groove 10a. That is, the holding plate 10 is moved in conjunction with the rotation of the drive disk 13, and by rotating the drive disk 13 by half a rotation, only the pitch between the long grooves 10a is moved in the guide direction of the guide rails 11 and 12. It is something that is moved.

The photo sensors 15 and 16 face the holding plate 10, and are fixed at positions facing the lower part of the opening 10b in the holding plate 10.

Further, the photo sensor 17 is inserted into the slits 13b and 13 of the driving disk 13 without using the holding plate 10.
It is fixed at a position directly facing part b. on the other hand,
At each portion of the slits 13b, 13b of the drive disk 13, reflecting plates 13c, 13c are fixed to the back side facing the photo sensor 17, and the detection light emitted by the photo sensor 17 is reflected by the reflecting plates 13c, 13.
The structure is such that the light is reflected by c. For this reason,
A slit 1 formed at the peripheral edge of the drive disk 13
3b and 13b are detected by the photo sensor 17.

At the bottom of the filter G of the holding plate 10, there is a reflector plate MR.
is fixed, and there is a reflector plate at the bottom of filter B.
MG is fixed. Furthermore, reflecting plates MD and MN are fixed to the lower part of the filter R.

In the reflector plate MR, the holding plate 10 is moved in conjunction with the rotation of the driving disk 13, that is, the holding plate 10 is moved in response to the rotational movement of the pin 13a on the driving disk 13 as the driving disk 13 rotates. When the filter G is driven and faces the drive disk 13, it is detected by the photo sensor 16. In addition, the reflector MG
is similarly detected by the photo sensor 15 when the holding plate 10 is driven to move and the filter B faces the drive disk 13. Furthermore, the reflector MD,
MN is similarly detected by the photo sensors 16 and 15 when the holding plate 10 is driven to move and the filter R faces the drive disk 13, respectively.

That is, when the filter ND is located on the optical path of the reduction lens 8, the detection output of the photo sensors 15 and 16 is
Since MN and MD are detected respectively, they are turned on and on (1, 1), and when filter R is located, the photo sensor 16 detects the reflector MR, so they are turned off and on (0, 1), and the filter G is turned on. is located, the photo sensor 15 detects the reflector MG.
is detected, so it becomes on and off (1, 0),
When filter B is located, nothing is detected in either case, so it becomes off, off (0, 0).

FIG. 4 is a circuit block diagram showing a control circuit for the drive motor 14.

This control circuit includes latches 20 and 21 that temporarily store input signals, a power-on reset 22 with a predetermined time constant, an AND 23, and a comparator 2.
4 and a display circuit 25.

The detection signal S ₀ of the photo sensor 15 is detected by the latch 20
sent to. The detection signal S ₁ of the photo sensor 16 is then sent to the latch 21 . Photo sensor 17
The detection signal P of the power-on reset 22 and the output signal of the power-on reset 22 are sent to the AND 23.
The output of the latch 20,2 is used as a latch trigger signal.
Sent to 1. Also, the control signals C ₀ and C ₁ are
The signal is sent to the comparator 24.

The comparator 24 compares the respective control signals C ₀ , C ₁ with the respective detection signals S ₀ , S ₁ , and when they are equal, this fact is displayed on the display circuit 25 and the , becomes an operation end signal _D2 indicating the end of the control operation of this control circuit. on the other hand,
If these are not equal, a drive signal to that effect
D ₀ and D ₁ are sent to the drive motor 14 . and,
The drive motor 14 is controlled to rotate forward or reverse by the drive signals D ₀ and D ₁ .

That is, in this control circuit, the detection signals S 0 and S 1 of the photo sensors 15 and 16 are latched at every timing of the detection signal P, that is, every timing when the photo sensor 17 detects the slit 13b, and each time the detection signals S ₀ and S ₁ are latched by the comparator 24. be compared. The drive motor 14 is driven to rotate in forward and reverse directions by the drive signals D ₀ and D ₁ that are the comparison results, and this rotational drive is performed by the control signals C ₀ and C ₁ and the detection signals S ₀ and
This is repeated until S ₁ matches. Therefore,
If each control signal C ₀ , C ₁ instructs the desired filter,
The control circuit shown in FIG. 4 is activated, that is, the control circuit controls the rotation of the drive disk 13 by the drive motor 14, so that the desired filter is automatically and accurately positioned on the optical path of the reduction lens 8. be done.

Note that the power-on reset 22 converts a signal that rises at a predetermined time constant to an AND 23 when the power is turned on.
The detection signal P of the photo sensor 17, which becomes the latch trigger signal for the latches 20 and 21, is applied to the AND2 after a predetermined time has elapsed since the power was turned on.
This is to allow the data to be sent from 3.

In other words, according to such a configuration, the filter
The shapes of ND, R, G, and B are molded to the minimum necessary size to cover the light receiving range X of the CCD sensor 9, and thus are miniaturized. and,
Since the filter group is held in a line by the holding plate 10, the height can be reduced. Therefore, by applying this, various image processing devices can be miniaturized.

Note that in this embodiment, the photo sensors 15, 1
Although 6 and 17 are of reflective type, they are not limited to this, and can be changed as appropriate, for example, they can be of transmissive type. Further, in this embodiment, the filter conversion device is applied to a color image reading device, but it goes without saying that the filter conversion device can also be applied to a color copying device and the like.

[Effects of the Invention] As explained above, according to the present invention, the filters are arranged in a row, resulting in a simple configuration,
A filter conversion device with reliable filter conversion operation can be constructed at low cost. In addition, the height can be reduced and the height does not increase even when the number of filters is increased, and by applying this, it is possible to downsize various image processing devices and reduce the cost of the image processing devices.

Furthermore, since the filter holding means is moved and driven by the rotation of the rotating member protruding at intervals equal to the interval between the driving grooves, half a rotation of the rotating member moves one pitch of the driving groove, that is, one filter. This makes filter conversion control easier.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view schematically showing the main components of a color image reading device to which an embodiment of a filter conversion device according to the present invention is applied, and FIG. 2 is a side sectional view of the color image reading device shown in FIG. 1. plan view of
3 is a plan view of the main part of the filter conversion device F, with a part of FIG. 2 viewed from the - arrow, and FIG. F...Filter conversion device, R, G, B, ND...
...Filter, 10... Holding plate (filter holding means), 10a... Long groove (driving groove), 11, 12...
Guide rail (guide means), 13... Drive disk (rotating member), 13a... Pin (drive member), 14
...Drive motor (drive means).

Claims (1)

[Claims] 1. A plurality of filters having different color separation hues are selectively switched and inserted between the optical paths, the plurality of filters are held in a line, and the filter arrangement direction is a filter holding means in which a plurality of orthogonal drive grooves open to at least one side are formed at predetermined intervals across the filter in the filter arrangement direction; a guide means for guiding the filter holding means in the filter arrangement direction; a rotating member rotatably provided with its rotation center substantially aligned with the open end of the drive groove on an extension line in the moving direction of the filter holding means; two driving members protruding at intervals equal to the driving groove spacing of the holding means and capable of fitting into the driving grooves; and a driving means for rotationally driving the rotating member; Due to the rotation, the two driving members alternately fit into the driving grooves of the filter holding means, and as the rotating member rotates, the fitting position thereof moves along the driving groove and the filter holding means is moved. A filter converting device characterized in that it is configured to be moved and driven along the guide means to position a filter of a desired hue between optical paths.