Note: Descriptions are shown in the official language in which they were submitted.
! IMPROVED M33THOD AND APPARI~TUS FOR IMAGE CAPTllRE
OF INFORMATION ON DOCUMENTS
l Field of the Invention
_.
2 This invention rela-tes to improvements ln document
3 processing, more particularly to improved methods and apparatus
4 for the image capture of information on a face of the documents,
and more particularly to an improved method and apparatus for
6 illuminating the documents for increased reliability of such
7 image capture.
8 Background of the Invention
9 Recently, increased efforts have been devoted to
improving the efEiciency of reading written or printed
11 information from the face of paper documents. For example, in
12 the area of processing of financial documents such as checks,
13 deposit slips, remittance advice stubs, and the like, the use of
14 image processing technology has been receiving increased
application. In accordance with typical image processing
16 techniques, doculllents are transported to a scanning station at
17 which a camera and assoclated electronlcs are used to capture and
18 digitize all or a portion of the image of a face of each of the
19 documents. The digitlzed image is stored and subsequently
processed, for example, to display the lmage (by way of a CRT,
21 for instance) to an operator for keying specific in~ormation into
22 the system processor; the document irnages also being used, for
23 example, for bank statement preparation and/or reproduced for
24 archlval storage on microfilm, magnetic tape, optical discs,
etc.
26 A chlef advantage of this technology is that the
27 document images, rather than the documents, are used for viewing
28 and processing, thus increasing -the speed and overall flexlbility
29 of the document processing operation, as well as reducing or
ellminating the need for retaining the documents themselves. The
31 archiving, cataloging, and other processes wh~ch are requlrecl for
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1 record-keeping purposes can be more efflclently carried out, and
2 additionally, the space required for such electronically-
3 reprodllced forms can be much reduced from that heretofore
4 requlred.
The increasing use of background lllustrations and
6 safety patterns on checks and other items, however, poses special
7 problems for the image processing of these financial documents.
8 First, these patterns and illustrations increase the amount of
9 data bit storage required in the system processor. Secondly, the
various scenes of mountains, seashores, animals, and the like
11 which are imprinted on the checks oftentimes obscure and
12 interfere with pertinent data Erom being image captured from the
13 face of the document, especially the si~natures and dollar
14 amounts written thereon. In particular, these patterns make it
difficult, if not lmposslble, for the camera to discriminate
16 between the important information which is to be captured from
17 the face of the check and the background illustrations.
18 Amplifying this problem is that conventional image processing
19 normally relies upon front lighting of the document and such
front llghting actually enhances the background patterns, which
21 in turn further obscures the information or data which is to be
22 detected or captured from the face of the document.
23 oblects and Summary _f the Invention
24 In llght of the above, it is therefore an initial ob~ect
of the present invention to provide a new and lmproved method and
26 apparatu~ in an image processing system for rellably detecting
27 land capturing information and other data imprinted or hand
28 written on checks and other financial documents.
29 It ls another ob~ect of the present lnvention to provlde
a new and lmproved method and apparatus for enhancing the ability
31 to image capture data from the face of patterned or illustrated
32 checks in a documen-t processing system while at the same time
33 ~linimlzing data storage capacity required for same.
~ 3~
1 It is another object of the invention to provide a
2 method and apparatus of the type described in which the
3 undesirable effects of front document lighting are minimized and
4 the reflected light variations due to imprinted design patterns
are minimized.
6 These and other objects, feature~ and advantages will be
7 apparent to those skilled in the art from the following detailed
8 description, when read in conjunction W7 th the accompanying
g drawings and appended claims.
In accordance with a broad aspect of the invention, an
11 apparatus and method are provided for uniquely illuminating the
12 financial document so as to enhance the electronic detection and
13 image capture of imprinted and handwritten information on the
14 ~aces of the document, as distinguished from the background
illustration or patterns on such document face. The illumination
16 approach provides back lighting of the document so that the light
17 passes through the document to an electroni.c detection means, such
18 as a document digitizing camera, whereby the imprinted or
19 handwritten information is emphasized or enhanced and the lighter,
or less opaque, background patterns are de-emphasized or
21 eliminated altogether.
22 Broadly stated, the invention is an improved method for
23 the image capture of data from the face of documents having
24 background patterns or i7lustrations of lesser opacity than the
opacity of the medium of which the data is formed, comprising the
26 step of: directing a first light at a back side of a document of
27 intensity sufficient to travel through said document and render
28 said patterns or illustrations substantially invisible to image
29 capture, thereby to enhance the image capture of said data;
concomitantly directing a second light at the front side of said
31 document; and captuxing the image data on said document from only
32 one of said sidesO
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1 In another broad aspect~ the invention is an apparatus
2 for enhancing the image capture of data from the face of documents
3 having background patterns or illustrations of lesser opacity than
4 the opacity of the medium of which the data is formed, said
apparatus comprising: means for transporting each of said
6 documents in a transport path past a viewing station operative for
7 capturing document data only from one side of said transport path;
8 image capture means disposed in front of said viewing station for
9 capturing the image of at least a portion of a face of said
documents; first illumination means for illuminating a back side
11 of said documents at said viewing station so as to render said
12 patterns or illustrations essentially invisible to said image
13 capture means and to enhance the image capture of said data; and
14 second illumination means for concomitantly illuminating the front
side of said documents.
16 Brief Description of the Drawinqs
17 Preferred embodiments of the invention are illustrated
18 in the accompanyi.ng drawings in which:
19 P.TGURE 1 is a perspective, diagrammatic illustration of
20 one preferred embodiment of the apparatus of the present
21 invention;
22 FIGURE 2 is a p~rspective, diagrammatic illustration of
23 an alternate embodiment of the apparatus of the invention for
24 focusing back-light onto a particular portion of the document;
FIGURE 3 is a perspective diagrammatic illustration of
26 another alternate embodiment of tAe apparatus of the invention
.
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1 for focllsing back llght onto a very small selectlve portion of
2 the document.
3 Detailed Descrip-tion of the Preferred Embodiments
4 Referring now to Flgure 1, the back-lighting apparatus
of the invention ls used in conjunction with known lmage capture
6 or detection means (not shown) which may be, for example, a
7 conventional document digitizing camera (and associated
8 electronics~ or other type of image scanning equipment. One type
9 of suitable image capture apparatus is described in U.S. Patent
4,510,619 and assigned to the assignee of the present invention.
11 A conventlonal transport assembly (not depicted~ is provided by
12 which documents 12 are manually or automatlcally transported
13 (along a transport guide 11) in the direction of the arrow A into
14 the viewlng area of the image detection means. The most widely
used image detection means is a digitizing camera ln which a
16 small area, such as the illustrated area 13, is scanned. As the
17 document 1~ is transported past the viewing area 13, a face of
18 the document 12 (or selected portions thereoE) are scanned, with
19 the captured image stored and used for subsequent processing, as
deslred. For the purpose of this description, and for
21 illustrative purposes, the document 12 ls a check haviny
22 background illustrations or patterns on the face of the check.
23 As illustrated, the check 12 has a number of MICR
24 (Magnetic Ink Character Recognition) characters 19,- usually alon~
a lower marginal area or field 20. As is conventional, various
26 lines and block 22 are provided indicating locations for entering
27 the identification of the payor and payee, dollar amount of the
28 instrument, etc. Of particular concern, patterns or scenic
29 designs 23 have been pre-printed on the face of th~ check
and, as shown, such designs may extend into the areas or fields
31 in whlch the MICR characters 19 are located or in whlch the
32 dollar amounts or payor/payee ldentlfications have been
33 ~handwrltten O prlnted. Som~ Of the prlnted characters 19 or
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1 handwritten data may ln fact be located directly over portions of I
2 the scenic design 23 so that such deslgn portions practically ,
3 obscure the important check data.
4 Two lamps, such as elongated fluorescent tubes 1~ and
16, are in conventional systems normally provided ad~acent to the I
6 front face oE the check 12. The tubes 1~ and 16 are typically I
7 located side-by-side, on each side of the viewing area 13, the j
8 detection means (carnera) ordinarily detecting light reflected
9 from the document 12 (and the data on the face of the document)
within the viewing area 13. It has been found that because of
11 the nature by which light is reflected from the document 12, and
12 particularly under the circumstances of this front lighting by
13 itself, that the dark areas of the design 23 oftentimes
14 completely obscure the information which is desired to be image
captured, particularly the handwritten informatlon (dollar
16 amount, slgnature, etc.), and the ability of the camera to
17 capture such information~
18 To overcome such problem, and in accordance with a
19 preferred embodiment of the invention, one or more lamps, for
instance fluorescent tubes 17 and 18, are disposed behind the
21 document 12, as shown in Figure 1. The lamps 17 and 18, ln the
22 preferr~d embodiment of Figure 1, back-light ea~h document 12
23 generally in the same area and in the same manner as the tubes 15 i
24 and 1~, only on the back side thereof. The result is that light ¦
from the tubes 17 and 1~ travels through the document 12 and
26 tends to ~wash out~' tha less opaque or halftone lnk that is
27 typically used for printing the scenic illustrations and safety
2~ patterns on the checks.
29 More specifically, the back-llghting approach of the !
invention takes advantage of the fact that the opacity of the i
31 medium of which the pertinent data that is desired to be image
32 captured ~dollar amounts, signatures, MIC~ characters) is printed
33 or written is greater than the opaclty of the ink used to print
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1 the background patterns and illustrations. Thus, the light from
2 the tubes 17 and 18 passes through the document, and in a
3 diffused manner through the designs and patterns 23, and is more
4 effectlvely blocked by the more opaque handwritten and printed
data, thus efectively washing out the background illustrations
6 and patterns, and enhancing the image capture of the pertlnent
7 data.
8 Additionally, digltizlng camera apparatus which is
9 typically used to "capture" the image in many document processlng
image systems essentially operates on the basic principal of
11 detecting and storing transltions between light and dark areas on
12 the document; and by utllizing the back-llghting technique of the
13 invention, the halftone patterned areas are washed out
14 sufficiently so that no light-to-dark transitions appear to occur
in those areas. Consequently, in addition to enhancing the
16 capture oE the relevant data from the document, the method and
17 apparatus of the invention enables a reductlon in the amount of
18 memory that is requlred to accompllsh the requlred storage and
19 processing.
It should also be noted that in optlmizlng the image
21 capture of the desired relevant data from the document, the data
22 must in the first lnstance be reliably detected; and there is
23 virtually no way to predict ln advance the type, nature or
24 quality of such data, particularly the handwritten data.
Accordingly, to achleve such optimization, the back lighting of
26 the document is preferably used in con~unction with the front
27 lightlng of the document, as shown in Figure l.
28 Furthermore, lt has been found that when such
29 combinàtion ls employed, it may be desirable to ad~ust the
relative intensities of the llght emi-tted from the rear tubes 17
31 and 18 wlth respect to the front tubes 15 and 16; and for thls
32 purpose, separate power supplies 25 and 26 are provided to
33 lndep dently control the respestlve lntenslties of the set oL
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1 tubes 15 and 16 and the set of tubes 17 and 18. In addition, it
2 may be desirable to use automatic gain type controls for
3 regulating the intensltles as a function of the amount of light
reflected from the document. secause the kind, quality and
nature of the particular documents belny processed may vary from
6 one geographlcal area of the country to the other, or even from I
7 batch to batch, some experimentation may be necessary to ¦
8 de-termine the desired respective light intensities from the front
9 and rear lights which will optimize image capture of the desired
data.
11 It should be appreciated that although elongated
12 fluorescent tubes 17 and 18 have been previously described as the
13 back-lightlng source, various other types of lighting means can
14 be alternatively employed. For example, one could use I
incandescent lamps or, alternatively, light sources which emit !
16 light of particular wavelength compatible with the spectral ¦
17 sensitlvity of the particular detection means.
18
If only particular areas of the document, rather than ¦
19 the entire document, are o~ lnterest ln particular applications,
the light apparatus can be arranged to back-illuminate primarlly, I
21 or only, that particular area of lnterest. For example, as shown ¦
22 in Figure 2, the rear llght arrangement may utillze a pair of ¦
23 vertically dlsposed and shaped llght plpes ~or other similar type
24 light-directlng means) 30 and 31 in combinat~on wlth one or more
lncandescent ~or other type) light sources 34 and 3s so as to
26 concentrate the light on a particular vertical segment at the
27 back of the document 12.
28 Alternatively, and as shown in Flgure 3, it may be !
29 desirable to back-illumlnate, for example, only a por-tion of the I
lower marginal area 20 of the document 12 whlch contain the MICR ¦
31 characters 19; and for this purpose, a llght p~pe ~Q having a ¦
32 narrow, shorter vertical height portion 41 aligned with, and
33 ad~acent to, the lower marginal area 20 can be employed w1th a
34 single incandescent lamp 43 used as the light ~source.
~33c~
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1 ~lthough the inventlon has been descr~bed and
Z illustrated wlth respect to partlcular preferred embodiments, it I
3 is understood that such descriptlon has been made by way of ¦
4 example only and that numerous changes in the combination and ¦
S arrangement of parts can be resort~d to by those skllled in the I
art wlthout departlng from the spirlt and the scope of the !
7 invention as herelnafter clalmed.
