JPH031659A - Planer scanning type picture reader - Google Patents

Abstract

PURPOSE:To designate a trimming area quickly with high accuracy by moving a dot projection image displayed on an original table to each required point and designating the area automatically based on the moving distance at that time. CONSTITUTION:The reader consists of prescribed light reflecting means 7-12, a point light source 13, drive means 14-17, 3-5 in main and subscanning directions, origin detection sensors 18, 6 and a trimming area calculation means (CPU or the like). Through the constitution above, when the light source 13 is lighted, its radiation light is projected onto an original on an original table 1 via the optical reflection means and an input optical system to form the projection image of the light source 13. Then each drive means moves the projection image to the origin on the table 1 at first and then moves the projection image of the original in the main and subscanning directions to make the projection image to coincide with each required point of the trimming area. In this case, each moving distance of the projection image from the origin to each required point by the sensors 18, 6 is detected. The CPU calculates the trimming area based on the distance.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a plane scanning image reading device, and in particular,
This invention relates to a technique for specifying a trimming area within a manuscript.

<Prior Art> Conventionally, in a plane scanning image reading device, a trimming area within a document is specified as follows.

This type of flat scanning image reading device is provided with a document table cover on the document table on which the document is placed, and which holds the document placed on the document table from above. A trimming table for specifying a trimming area is provided on the cover. The trimming table is a transparent sheet on which a grid scale is formed, and is attached to the document table cover so as to be openable and closable.

When determining a trimming area within a document, the trimming table is opened, and after the document is centered upward at a predetermined position on the document table cover, the trimming table is closed. In this state, since the trimming table is transparent, it is possible to visually confirm the document and the grid scales superimposed thereon from above the trimming table.

Using this grid scale, the operator reads the coordinate values of the area to be trimmed in the document, and the trimming area is designated by inputting the coordinate values manually from the operation panel.

<Problems to be Solved by the Invention> However, according to the above-mentioned conventional apparatus, the trimming area in the document is read visually using the grid scale of the trimming table, which tends to cause reading errors due to parallax, making it difficult to trim. There is a problem that the area cannot be specified with high precision.

In addition, it is necessary to enter the read coordinate values of the trimming area by keystroke again, so there is another problem that specifying the trimming area is time-consuming.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a plane scanning image reading device that can accurately and quickly specify a trimming area within a document. .

Means for Solving the Problems> In order to achieve the above objects, the present invention has the following configuration.

That is, in the present invention, a document placed on a document table is irradiated with linear light, and an image of the document is formed on a CCD line sensor via an input optical system corresponding to the irradiated area, and 18 CCD line sensors In a plane scanning image reading device that reads an image in the main scanning direction and performs sub-scanning by moving a linear light relative to the original table, a device is provided on the optical path from the input optical system to the CCD line sensor. a point light source provided on an optical path branched by the light reflecting means at a position equivalent to a CCD line sensor with respect to the document table; a first driving means for moving a projected image of the irradiation light from the point light source projected onto the original table in the main scanning direction on the original table; and a first driving means for moving the projected image in the sub-scanning direction on the original table. two driving means; a first detection means for detecting a moving distance of the projected image in the main scanning direction; a second detecting means for detecting a moving distance of the projected image in the sub-scanning direction; a trimming area for calculating a trimming area based on each movement distance detected by the first detection means and the second detection means when the projected image is moved to a required location related to the trimming area of the original on the original; It is equipped with a calculation means and.

Effect〉 The effects of the configuration of the present invention are as follows.

When specifying trimming within a document, when a transmissive or reflective document is placed on the document table and a zero-point light source is turned on, the irradiated light passes through the light reflection means and the input optical system. The image is projected onto the original on the original table through the image. Then, the first driving means and the second driving means first move the projected image to the origin on the document table, and then move the projected image at the origin in the main scanning direction and the sub-scanning direction, so that the projected image match each required point in the trimming area. At this time, the moving distance of each of the projected images from the origin to each of the required points is detected by the first detection means and the second detection means. Based on these movement distances, the trimming area is calculated by the trimming area calculation means.

<Example> Hereinafter, an example of the present invention will be described in detail based on the drawings.

■Tsuchikuse■ The schematic configuration of a plane scanning type image reading device according to this embodiment will be explained with reference to FIG. Note that FIG. 1(a) shows a plan view of the device, and FIG. 1(b) shows a front view.

In the figure, reference numeral 1 denotes an original table, and this original table 1 is provided with a glass plate 2 on which a transmissive original (not shown) is set. A screw shaft 3 is screwed into one side of the document table 1 in the sub-scanning direction, a guide rail 4 is fitted into the other side, and a pulse motor 5 is connected to one end of the screw shaft 3. The document table 1 is configured to be fed in a sub-scanning manner by the following. The above-mentioned sub-scanning feed mechanism corresponds to the second driving means in the configuration of the present invention. Note that the original table 1 is provided with an origin detection sensor 6 for detecting the origin position of sub-scanning feed.

The reflecting mirrors 7, 8, 9 and the lens unit 1O are an input optical system for reading the image of the original, and the original table 1
The transmitted light from the original set is imaged on the CCD line sensor II via the manual optical system. The lens unit 10 projects the original image onto the CCD line sensor 11 as an erect image. The CCD line sensor 11 is composed of a large number of pixel groups arranged in the main scanning direction, and reads images in the main scanning direction by self-scanning each of these pixels.

A half mirror 12 as a light reflecting means is interposed on the optical path from the lens unit 10 to the CCD line sensor 11. On the optical path branched by the half mirror 12, the CCD line sensor 11 is connected to the original table l. That is, the distance from the half mirror 12 on the optical path is from the half mirror 12 to the CCD line sensor 1.
A visible semiconductor laser 13 as a point light source is provided at a position equal to the distance from the point light source to the point light source.

The laser 13 is driven by a main scanning feed mechanism, which will be explained next.
It is configured to be movable in the main scanning direction.

In the main scanning feed mechanism, a screw shaft 15 is screwed onto a laser movable base 14 to which a laser 13 is attached, a guide rail 16 is fitted, and a pulse motor 17 connected to one end of the screw shaft 15 is driven. By laser 13
is configured to drive in the main scanning direction. The main scanning feed mechanism described above corresponds to the first drive means in the configuration of the present invention. The main scanning feed mechanism is equipped with an origin detection sensor 18 for detecting the origin position of the main scanning feed, and the read image at this origin position becomes the position of the first pixel of the movable pixels of the CCD line sensor 11. It is pre-positioned.

Next, the configuration of the control system of this embodiment will be explained with reference to FIG.

The CPU 20 has functions corresponding to the first detection means, second detection means, and trimming area calculation means in the configuration of the present invention. Such a function will be explained in detail in the operation description below. The CPU 20 is connected via a pass line 21 to a ROM 22 for program storage, a RAM 23 for data storage, a motor control circuit 24 for the pulse motor 5,
A motor control circuit 25 for the pulse smoke 17, a control register 26 for the laser 13, an indicator 27 that displays the moving distance in the main scanning direction, and an indicator 28 that displays the moving distance in the sub-scanning direction.
, and registers 29 and 30, respectively.

The second register register memorizes and holds the states of the origin detection sensor 6 and I8, respectively, and the register 30 stores the states of the origin detection sensor 6 and I8, respectively, and the register 30 stores the states of the origin detection sensor 6 and I8, respectively.
The states of the drive switch SWl of the document table 1 and the drive switch SW2 of the original table 1 are stored and held. CPU
20 constantly monitors the status of these registers 29 and 30 by polling them.

Switch SW1. SW2 is a momentary switch operated by an operator.

When the switches SWI and SW2 are in the neutral state, the register 29
rl is set in each terminal B0 to B3, and the switches SWI and SW2 are turned to the contact T1 side, Bo e
La child 2'01, B+ terminal 2' IJ, 'OJ' is set to the Bz terminal, and rlJ is set to the B3 terminal, respectively. Also, when the switches SWI and SW2 are pushed to the contact T2 side, 11 is placed on the B0 terminal, rob is placed on the B terminal, [3, and ' is placed on the terminal.
rQJ is set to the IJ and Bl terminals, respectively.

The CPU 20 outputs necessary pulse signals to the motor control circuits 24 and 25 according to the levels of the terminals B0 to B of the register 30, and controls the laser movable table 14 and the document table 1.
are driven as follows.

That is, the laser movable table 14 has terminals B, , B, rlJ,
rl", it is maintained in a stopped state when "IJ.

When rQJ, it is driven in the direction of the main scanning origin and "OJ.

``When it is 11, it is driven in the direction away from the origin.

The manuscript table 1 is B2. B3 terminal f) < r I J
.

When rlj, it is maintained in a stopped state, when rlJ and raJ, it is driven in the direction of the sub-scanning origin, and when roJ and rlJ, it is driven in a direction away from the origin.

The switch SW3 is a switch operated by the operator when the projected image of the point light source onto the document table 1 matches a predetermined point in the trimming area, and is connected to the CPU 20 via the interrupt control circuit 31. .

Next, the operation of specifying a trimming area using the apparatus according to this embodiment will be described with reference to FIG.

FIG. 3 is a plan view showing the original fg32 placed on the glass plate 2 of the original table l.

(2) First, the laser 13 is turned on by outputting a laser drive signal from the CPU 20 to the control register 26. The beam irradiated from the laser 13 is transmitted to the half mirror 1
2. Lens section 10. The light then enters the glass plate 2 via the reflecting mirror 9°8.7, and a dotted projected image is projected onto the glass plate 2.

(2) Next, in order to return the document table 1 and the laser movable table 14 to their original positions, the switches 5WISW2 are each turned to the contact T2 side. This makes register 3
The 80 terminal of 0 is set to 'IJ, the Bl terminal is set to roJ, and the [3, terminal is set to 'IJ, t3+ terminal force rO). Based on this, the CPU 20 controls the motor control n circuit 2.
4. At 25, output the required pulse signal and move the laser movable table 1.
4 and the original table 1 in the direction of the origin.

When the laser movable table 14 and the document table 1 reach their respective origins, the origin detection sensors 6 and 18 are activated.
r□, 1 is sent to the B, , B, terminals of the register 29, respectively. Based on this, the CPU 20 stops outputting pulse signals to the motor control circuits 24 and 25, so that the laser movable table 14 and the document table 1 stop at their respective origins.

At this time, by driving the laser movable table 14 and the document table 1 described above, the point-like projected image projected on the glass plate 2 of the document table 1 also moves in the main scanning direction and the sub-scanning direction, and the laser movable table 14 and the document table 1 are driven. When the original table l returns to the origin, the projected image is located at the origin AI on the glass plate 2 shown in FIG.

■ When the setting of the laser movable table 14 and original table l to the origin position is completed, switch SWI is turned on.

SW2 is operated again, and the dotted projected image at the origin A1 is adjusted to the desired rectangular trimming area 33 of the original 32 (in the figure,
The laser movable table 14 and the document table 1 are driven until they coincide with the first point B1 (indicated by a broken line).

At this time, the CPU 20 counts the number of pulse signals respectively sent to the motor control circuits 24 and 25. When the projected image moves away from the origin A, each of the pulse signals is amplified and counted,
Each time it moves toward the origin A, it is counted down.

Here, the minimum moving distance of the laser movable table 14 driven by one pulse of the pulse signal given to the motor control circuit 25 for main scanning feed control is ll, and the total distance of the pulse signal given to the motor control circuit 25 is ll. If the numerical value is 11, the moving distance d of the projected image in the main scanning direction.

is expressed as follows.

d, 1 = ffi, Xnl ---
h-(1) Here, the screw pinch of the spiral shaft 15 is determined in advance so that the minimum moving distance l is an integral multiple of the pixel pitch of the CCD line sensor 11.

A pulse signal for main scanning feed is output to the motor control circuit 25, and a moving distance d4 of the projected image in the main scanning direction is calculated by the CPU 20 based on the above equation (1).
The result is displayed on the display 27.

Similarly, the moving distance d in the sub-scanning direction is calculated based on the following equation (2), and the result is displayed on the display 28.

d, -2□ ×n2 ・・・・・・(2
) Here, l is the motor control circuit 2 for sub-scanning feed control.
4 indicates the minimum moving distance of the document table 1 driven by one pulse among the pulse signals given to the motor control circuit 24, and n2 is the count value of the pulse signal given to the motor control circuit 24.

■ The projected image is the first point P of the trimming area 33.

If it matches, the operator operates the switch SW3 to output C via the interrupt control circuit 31.
An interrupt command is given to the PU20.

Based on this command, the CPU 20 outputs the pulse count value nl+n! is stored in the RAM 23, and the CPU
The count value n l + n 2 within 20 and the display 2
The display of 728 is erased.

(2) After specifying the first point P1 of the trimming area 33, the process moves on to specifying the second point P2. In this case, by operating the main scanning feed switch SWI to drive the laser movable table 14, the dot-like projection image at point P1 is transferred to point P2.
move it to At this time, the number of pulse signals output to the motor control circuit 25 is counted in the same way as in the case (2) above, and the distance traveled from the first point P1 is displayed on the display 27.

(2) When the projected image coincides with the second point P2, the operator operates the switch SW3. As a result, point P
The pulse count value n when the projected image moves from , to point P2 is stored in the RAM 23, and the count value of the CPU 20 and the display on the display 27 are erased.

(2) After specifying the second point P of the trimming area 33, the process moves on to specifying the third point P3. In this case, the sub-scanning feed switch SW2 is operated to move the dotted projected image at point P2 to point P3. At this time, the pulse signals output to the motor control circuit 24 are counted, and
From point P2 to point P.

The distance traveled is displayed on the display 28.

(2) When the projected image coincides with point P3, the operator operates switch SW3 again. As a result, point P2
Pulse count value n when the projected image moves from to point P
4 is stored in the RAM 23, and CI'tJ20
The counted value and the display on the display 28 are erased.

■ Count value n stored in RAM23 as described above
The trimming area is calculated from l+nz+ns and na as follows.

The trimming area in the main scanning direction is represented by the number of pixels of the CCD line sensor 11 based on the pulse count value n + + 13 in the main scanning direction.

That is, C with respect to the minimum movement distance 11 of the laser movable table 14
When the number of pixels of the CD line sensor 11 is N, the number of pixels N1 corresponding to the above count value n is calculated from the following equation (3), and similarly the number of pixels N3 corresponding to the count value n is calculated from the following equation (4). )
Calculated from.

N + = N X n + −・”
(3) N, = Nxn, ......(
4) The trimming area data in the main scanning direction calculated in this way is stored in the RAM 23.

On the other hand, as the trimming area data in the sub-scanning direction, the pulse count values nz and na in the sub-scanning direction are used as they are.

[Phase] Based on the trimming area data obtained as described above, in the main scanning direction, image data of each of the N1 to N+N pixels from the first picture of the CCD line sensor 11 is read, In the sub-scanning direction, the image data of the CCD line sensor 11 is read from the 02nd pulse signal to the n2+nth pulse signal sent from the CPU 20 to the motor control circuit 24.

FIG. 4 is a schematic diagram of the main parts of a plane scanning image reading device according to a second embodiment of the present invention.

In the figure, each part indicated by the same reference numeral as in FIG. 7 and a reflecting mirror 8.9 are screwed together to the screw shafts 3a and 3b, respectively, as in FIG. 1, and each screw shaft 3a.

3b is connected to a gear box 50 and is rotationally driven by a pulse motor 5, and at this time, the reflecting mirror 7 is moved in the sub-scanning direction at a speed of 2.
The original is scanned in the sub-scanning direction by moving the set of reflecting mirrors 8 and 9 in the sub-scanning direction at half the moving speed of the reflecting mirror 7.

Also in such an apparatus, a laser 13 movable in the main scanning direction is provided between the lens unit 10 and the CCD line sensor 11 to detect the moving distance in the main scanning direction, as in the first embodiment. By detecting the moving distance of the reflection mirror 7 in the sub-scanning direction, the trimming area can be designated as in the first embodiment.

The feature of the present invention is that the trimming area is automatically specified based on moving a point-shaped projected image projected on the document table to each required point related to the trimming area. The shape of the image and the calculation method of the trimming area data are arbitrary. For example, when specifying a polygonal trimming area as shown in FIG. Specify each point by
The trimming area may be determined by calculating (m+ +rr++, mz).

In addition, when specifying a circular trimming area as shown in Fig. 5(b), line-sequential trimming is performed based on specifying the center point P and an arbitrary point P2 on the circumference. The trimming area may be determined by calculating the coordinate values of the intersection points Q, , Q, between the scanning line and the circular trimming area.

Further, in the above embodiment, in order to facilitate understanding of the explanation, the case where the original image is read at the same magnification through the lens unit 10 was taken as an example.
It can also be applied to the case where the image is enlarged and read.

For example, when the lens unit 10 is set to an arbitrary magnification M,
The trimming area may be determined based on the value obtained by multiplying the count value nI""n4 of the pulse signal by 1/M.

Further, the point light source is not limited to a visible semiconductor laser, but may be configured such that irradiated light from a high-intensity light emitting diode lamp is extracted through a point-like aperture.

Furthermore, the means for moving the projected image on the document table in the main scanning direction is not limited to moving the point light source itself; it is also possible to fix the point light source and move the document table in the main scanning direction. It is also possible to

Furthermore, as a light reflection means provided on the optical path from the input optical system to the CCD line sensor, in addition to the half mirror as in the above embodiment, a retractable total reflection mirror or a A total reflection mirror or the like can also be used.

In addition, if the original table 1 and the laser movable table 14 are configured to be able to switch between high-speed feeding and low-speed feeding, the dotted projected image can be moved at high speed to near the desired point in the trimming area, and then the point-like projection image can be moved at low speed. Since the point projection image can be precisely positioned at that point, it is preferable for specifying the trimming area more quickly and accurately.

Further, although the embodiments have been described using a transmissive original as an example, the present invention can also be applied to a case where it is checked whether a reflective original is included in the trimming area.

<Effects of the Invention> As is clear from the above description, according to the present invention, the point-like projected image projected on the document table is moved to each required point in the trimming area of the document, and the projected image is moved at that time. Since the trimming M range is automatically specified based on distance detection, the trimming range is read visually using a grid scale, compared to conventional equipment that requires manual input. The trimming area can be specified accurately and quickly.

[Brief explanation of drawings]

Figures 1 to 3 relate to the first embodiment of the present invention.
2 is a schematic block diagram of the control system, and FIG. 3 is an explanatory diagram of the trimming area designation operation. FIG. 4 is a schematic configuration diagram of the second embodiment of the present invention, and FIG. 5 is an explanatory diagram of a modified example of the trimming area designation operation. 1... Original table 2... Glass plate 6.18.
... Origin detection sensor 7.8.9 ... Reflection mirror 10 ... Lens 11 ... CCD line sensor 12 ... Half mirror 13 ... Laser 32 ...
・Manuscript 33...Trimming area applicant
Sugi, Patent Attorney, Dainippon Screen Manufacturing Co., Ltd.
Tsutomu Tani Figure 2 Main scanning direction Figure 3 Whistle Figure 4 Main scanning direction Main scanning direction Figure 5 (b)

Claims (1)

[Claims] (1) The original placed on the original table is irradiated with linear light, and the original is sent to the CCD via the input optical system in accordance with the irradiated area.
In a plane scanning image reading device that forms an image on a line sensor, reads the image in the main scanning direction with the CCD line sensor, and performs sub-scanning by moving the document table and the linear light relatively, the input A light reflecting means provided on the optical path leading from the optical system to the CCD line sensor, and a point light source provided on the optical path branched by this light reflecting means at a position equivalent to the CCD line sensor with respect to the document table. and a first driving means for moving a projected image of the irradiation light of the point light source onto the document table via the light reflection means and the input optical system in the main scanning direction on the document table; and the projected image. a second driving means for moving the projected image in the sub-scanning direction on the document table; a first detecting means for detecting the moving distance of the projected image in the sub-scanning direction; and a first detecting means for detecting the moving distance of the projected image in the sub-scanning direction. 2 detecting means; and when the projected image is moved to a desired location on the document placed on the document table in relation to a trimming area of the document, the first detecting means and the second detecting means detect the projected image. A plane scanning image reading device comprising: a trimming area calculation means for calculating a trimming area based on each moving distance.