JPS58108862A - Original reader - Google Patents

Abstract

PURPOSE:To prevent omission of read and repetitive read of information through a simple constitution, without reference to the optical-axis direction of a lens for the light irradiated from the normal position of an original to be read, by using plural reading elements. CONSTITUTION:Image formation luminous flux from an area between l' and l'' behind a lens 4 (image field side) and that from an area between l'' and l''' are directed differently to illuminate CCDs 5a and 5b arranged at different positions. Through the single lens 4, the linear part l to be read is projected on those two CCDs 5a and 5b as split parts, so principal beams 9b and 9c of light directed from the boundary l'' between the two areas of said part l to be read coincide with each other up to a half-mirror 8 through the lens 4. Therefore, even if original supporting glass flexes and even if an original floats over the glass, such a trouble that information read at the part l'' disappears or is read duplicatively by the two CCDs.

Description

[Detailed description of the invention] JIL in the general office where the desired company is formed based on the number
Regarding the scar removal device.

There are many devices that digitally read ripples *m* using a solid-state image sensor such as a company COD as a reading element in the above-mentioned R image device. ,・For example, 12 dots/- or 16 dots/l for an A4 paper 297 mm in the longitudinal direction.
When it is desired to remove defects with 1 Iol, the required number of pixels of a solid-state imaging device such as a CCD is as large as 6564 in the former case and 4752 in the latter case.

By the way, the current maximum number of pixels in COD is 2048,
For this reason, a so-called split imaging method has been adopted, as known from Japanese Patent Laid-Open No. 1i854-102820, in which two or six or nine or more 5[00D's are used in parallel in the electrical scanning direction, that is, the main scanning direction. There is.

The linear part to be read in the main scanning direction of the document is divided into a plurality of areas according to the number of ≦COD, and each COD is divided into a plurality of areas.
However, the boundaries of each area are taken in advance, and wIeMiL is created only by one of the CODs.
It is electrically controlled so that

The principle of a conventional reading device of this type is as shown in FIG.

In Figure 1, C111L is placed on a transparent original support stand (not shown).
The area from the edge 1&' to the center 11L' of the long linear reading part in the vertical direction (main scanning direction) of this manuscript 1a is covered by the lens 4a. by CCD5aL:I) into the reading area.

In addition, the area from the central part 1&' to 1/ is projected and imaged by the lens 4b onto the WIt capture area of C0D5b.
The reading area of D5m and 5b is a long straight line in the vertical direction in the plane of FIG. 1, and C0D5a and 5b electrically scan the image in this direction and convert the optical image into an electrical signal. In other words, 0
GD5t reads from i a/ to 1sLl, and CCD
5b reads from 1 at to 1C. Therefore, manuscript 1a
Alternatively, a unit in which the lens 4b, CCD 5a, and 5b are integrated is arranged in a direction perpendicular to the plane of FIG.
The scanner moves in the sub-scanning direction) and performs fine scanning of the document, reading it from one end to the other. In addition, 9a and 9b are 1
a′.

From 1a' (chief ray directed to 3CD5a, 9c, 94
is the principal ray directed from 1a, 1m' to ccn5b.The above configuration has the following disadvantages.In other words, since the imaging principal ray generally has an oblique angle with respect to the document WIK, the document platen glass is If the original is bent by the weight of a book or the like or if it floats above the glass, information will be missing or overlapped at each boundary of the divided portion to be read. To explain this using Fig. 1, in Fig. 1, 1a is the normal document position, 1b
1C is the document position when the document platen glass (not shown) is blurred.
is the position of the manuscript near the center of a book etc. opened in the middle, etc.
When the document table glass (not shown) is bent, the document is at position 1b, but the positional relationship between the imaging lenses 4a, 4b and the solid-state image sensors 5a, 5b remains unchanged. Maximum-angle imaging chief rays 9a, 9b, 9c,
9d is at the same angle as when the original is placed at the normal position #It1a, . Therefore, the information that was in part A of the manuscript will be missing.

On the other hand, when the original is lifted from the gripping glass to the position 1C, the information 1m in the part B of the original 1c is 21
The object of the present invention is to solve the above-mentioned problems and provide a Kudomi Castle device. FIG. 2 shows an embodiment of the present invention. Lol! , 2, the ripple*document placed on the document support glass (not shown) is fed in the direction of arrow S (sub-scanning direction). The linear object to be read at facing the main scanning direction of the original 1i11 is a single lens 4.
The ocOD5a is projected and imaged onto the linear reading sections of the two COD5a t5b.

The action of 5b is the same as described above.

The area from the end I' to the center r of the part to be read j is made into a linear reading part of 00D5* by the lens 4, and the area from the center 51' to the other end 161'' is made into a cc by the same lens 4.
The straight line j[ilK projection image of p5b is formed. 21 above
Pixel ij OCD 5 a or C (3D
5b.

The linear reading sections of the CCDs 5a and 5b are oriented in a direction corresponding to the longitudinal direction of the object M/ to be read, but since the object sl to be read is projected by the single lens 4 as described above, the C0D
When 5a and 5b are arranged on one straight line, the boundary It
It becomes difficult to project s l' onto both the CCD 5aK and 511. Therefore, at the rear of lens 4 (I#!Kai@)
The imaging light flux from the region between ', l' and J#, II
The CCD 5 which directs the 4a element beams from the area between 1 and 1 in different directions and directs each imaging light beam to a CCD 5 arranged at different positions.
a, 5b. For this reason, in the embodiment shown in FIG. 2, a half mirror 8 is placed behind the lens 4 to divide the combined 1112-element bundle from the lens 4. Therefore, the original C0D5kK incident on the regions between l' and l' that passed through the half mirror 8 was I that was reflected by the half mirror 78.
I, nine bundles 1d from the area between C7, OCD 5a
incident on .

As described above, since the linear scattered part I is divided and projected into two (30D 5 a + 5 b) by the single lens 4, from the boundary I' of the two areas of the part to be read I, 0CD5a,
The principal light directed toward 5b +1!9 b, 9 at; L, passes through the lens 4 and reaches the half mirror 8. Therefore, as mentioned above, the document support glass may become damaged or
Even if the information rises from the supporting glass, it is possible to prevent the inconvenience that the information removed at the portion l' is missing, or that a is removed twice by the two QC and D.

In addition, the main yr- directed from l' to GGD5&, 5b, respectively.
The lens 4.0 (3D5a
.

5b may be determined (the position of the lens and COD may be set further back than the illustrated position or even closer to the hand), but in this case, the document support glass may be bent as described above, or Ms may be placed on this glass. If it rises from the surface, 0GD5 a * 5 b
The range to be captured may change slightly, that is, the position of I' may shift slightly to the right or left, and the magnification may be slightly different on the left and right sides of the image when reproducing the image.
Lens 4, CGD5a.

sbu main jt, *9 b, 9 a Ka111 state I
Hi) It is best to position it perpendicular to ljLN I K as shown in the figure. Also 1 yuan 1i19m), 9
0 and the lens original axis X do not necessarily have to match, but to improve image quality,
From the viewpoint of ease of balancing the amount of light on b, it is preferable to make the lens original axis X coincide with the main jtis 9b, 9C. Therefore, as shown in Figure 2, the lens source @X and the chief ray 9
The lenses 4. C0D5a, 5
It is better to set the position and direction of b.

In FIG. 2, 6 is a lamp that illuminates the line portion I to be read of the document 1, and 7 is a fixed mirror that reflects the light beam from the line portion E to be read in a direction substantially parallel to the surface of the document and directs it to the lens 4. It is.

In the above example, the original 1 was moved in the S direction and optically scanned in the sub-scanning direction, but the original 1 was held fixed and the lamps 6, 1 and 7
．． To hold the lens 4 r OG D 5 a, 5 b integrally and move it in the S direction with respect to the original 1 K
or between the fixed-foot original and the fixed-foot lens.
By moving the document, the document may be optically scanned in the sub-scanning direction.

In any case, according to the present invention, in an apparatus using a plurality of reading elements, even if the position of the face sales source deviates from the normal position in the direction of the lens base axis, missing information and redundant reading of related information can be prevented. This can be prevented with a simple configuration.

[Brief explanation of the drawing]

Figure M1 is a detailed diagram of an example, and Figure 2 is a diagram of an embodiment of the present invention. 1 is Hamontorihara Kusunoki, 4 is lens, 5a, 5b is COD, 8
is a half mirror, l Fi is a straight rippled part. Izuhito Canon Co., Ltd. Agent Gi Marushima -62'￥ Heyo A

Claims (1)

[Claims] Covered! The first border of the Hamonshiki part of Toribara side
and a second area are projected onto the first and second reading elements, and the first and second areas of the part to be read are shared between the first and second reading elements. In the imaging device, the gIILs to be detected are projected onto the first and second reading elements using one lens, and at this time, a -7 mirror is placed after the lens, and the light beam transmitted through the half mirror is projected onto the first and second reading elements. A document reading y4L device characterized in that a second reading element receives a light beam reflected by a reading element.