Method and Apparatus for Print Verification

1. Field of the Invention

The present invention relates to a method and apparatus for print verification and, more particularly, to a method and apparatus for verifying that printed number sequencing on documents is correct.

2. Description of the Related Art

A common printing application involves printing on pre-printed, sequentially numbered forms. Examples of this type of printing include check printing, insurance policies, receipts, etc. The sequential numbering on these forms is particularly important since the number information is often used to guarantee traceability, facilitate record keeping, etc. In applications such as check printing, it is crucial that each individual document be readily identifiable and the correct number is printed in a proper location. Accordingly, it is desirable to quickly and easily verify that the printed information is properly associated with the printed form.

U.S. Pat. No. 4,645,240 to Whitehead et al discloses numbered documents, each of which has a unique identifying number. In order to prevent unauthorized duplication of the documents, at least two characters in the identifying number differ from one another in at least one visible characteristic such as size.

U.S Pat. No. 4,733,887 to Mowry Jr. discloses a method of preparing secure financial documents in which a major amount, such as dollar amount, is printed in a white on black pattern, while a minor amount, such as a cents amount, is printed in a black on white pattern. The printing patterns are used in order that any alteration of the document is difficult.

While the related art references disclose manners in which documents can be produced to prevent unauthorized alteration, the references fail to disclose any manner in which the printed material on the documents can be verified. Accordingly, there still exists a need for a method and apparatus for print verification which quickly and easily enables verification of the printed material on the documents.

An object of the present invention is to provide a method and apparatus which facilitates verification of printed information on documents.

Another object of the present invention is to provide a method and apparatus for verifying printed information which does not consume an excessive amount of time.

A further object of the present invention is to provide a method and apparatus for verifying printed information which does not significantly increase the costs associated with the printing process.

To achieve the foregoing and another objects and to overcome the shortcomings discussed above, a method and apparatus for verifying printed information on documents is provided. The pre-printed information is printed in a first color at a desired location on the document. Thereafter, the desired information is printed at the same location in a second color which is different from the first color such that the printed information in the second color overlies the printed information in the first color. If any of the information printed in the first color is left exposed and is not covered by the information printed in the second color, it is determined that improper printing has occurred.

The invention will be described in detail with reference to the following drawings wherein:

FIG. 1 is a block diagram of an apparatus used for printing verification;

FIG. 2 shows a pre-printed number printed in a first color according to the present invention;

FIG. 3 shows a properly printed number following printing in a second color by a printing unit according to the present invention;

FIG. 4 shows a printing discrepancy detected after printing in the,, second color by the printing unit of the present invention; and

FIG. 5 s an alternate printing discrepancy detected following printing in the second color by the printing unit of the present invention.

Referring now to the drawings, and particularly to FIG. 1 thereof, an apparatus 10 for verifying printed information on documents is illustrated. Apparatus 10 includes a supply 14 which supplies documents 12 having information printed thereon and a receiver 16 for receiving the documents. The information printed on documents 12, such as number information, is printed in a first color. The documents 12 are located on a belt 18 which travels around, for example, spaced rollers 20 and 22. As the documents 12 are provided to belt 18 from supply 14, belt 18 travels to provide each document 12 in confronting relationship with a printing unit 28.

Printing unit 28 operates to print desired information, such as sequential numbers, on each document 12. Printing unit 28 prints the desired information in a second color which is different from the color of the preprinted information provided on the sheets in supply 14. The desired information which is printed in the second color corresponds to the information, e.g., the particular numbers, that should have been printed in the first color. The desired information is further printed in the particular location where the information in the first color should have been printed. Printing unit 28 prints the information in the second color such that the information overlies the information printed in the first color. Printing unit 28 prints the desired information in a font, size, etc. corresponding to that of the pre-printed information. Documents 12 then travel past printing unit 28 to a sensing means 30.

Sensing means 30 can comprise, for example, a photosensitive light sensing means which transmits light to a specified location of said document where the information is printed, the photosensitive light sensing means then receiving the light reflected by the documents. Sensing means 30 detects whether any of the information printed in the first color remains exposed after printing unit 28 prints the information in the second color. If any of the information printed in the first color does remain exposed, an indication can be made by indicator 32 that the information printed in the first color on the particular document has been improperly printed. The indication can, for example, be audible or visual.

A controller 24 controls operation of the printing unit 28, sensing means 30 and indicator 32. Controller 24 further controls the rotational movement of rollers 20 and 22 to control the delivery of the documents to the printing unit 28 and sensing means 30. Controller 24 thus controls apparatus 10 such that, as rollers 20 and 22 operate to move belt 18 to deliver the documents 12 in confronting relationship with printing unit 28 and sensing means 30, the printing unit 28 and the sensing means 30 will be selectively operated to print information in the proper location on each document 12 and to sense exposure of the information printed in the first color at the proper location.

Once it has been determined that the information printed in the first color is not exposed, apparatus 10 provides verification that the documents supplied from supply 14 have been properly printed. In contrast, if improper printing of the information in the first color is sensed, the particular improperly printed document or an entire set of documents can be discarded and proper printing can subsequently be performed.

FIG. 2 illustrates an example of printed information on a document supplied from supply 14. This information is printed in a first color, in this example, gray.

FIG. 3 illustrates an example of properly printed information provided on a document 12 after the information has been printed in the second color, in this example, black. As shown in FIG. 3, the information printed in the first color is entirely covered by the information printed in the second color, thus leaving no exposed portions of the information printed in the first color. This information is thus determined to have been properly printed.

FIG. 4, in contrast, illustrates an example of information which was improperly pre-printed. The information printed in the first color (i.e., 34) and the information printed in the second color (i.e., 36) are different. Accordingly, when the information is printed in the second color over the information printed in the first color, portions of the information printed in the first color (i.e., portions of the 4) remain exposed. It is thus determined that improper printing of the information in the first color has been performed. The printing can thus be corrected.

FIG. 5 illustrates another example of improperly printed information. While the information printed in the second color (black) is the same information printed in the first color (gray), portions of the information printed in the first color remain exposed due to mis-registration during the process of printing in the first color. In certain applications, for example, check printing, it is necessary to print the information in an exact position. Accordingly, mis-registration during the printing process can be detected by the method and apparatus of the present invention.

The present invention thus provides a simple and efficient manner to verify the integrity of information printed on documents. Accordingly, document printing can be reliably performed without consuming extraordinary amounts of time and materials.

While the invention has been described in conjunction with a specific embodiment, it is readily apparent that various embodiments can be used to verify the integrity of the printed information. For example, various sensing means can be used to detect exposure of the information printed in the first color. A light emitter could be provided on one side of the document and a light detector could be provided on an opposite side of the document to detect light transmitted through, not reflected by the document. The print controller 24, printing unit 28, sensing means 30 and indicator 32 could be provided in conjunction with a printer which prints the information in the first color to reduce the time necessary for the printing and verification operations. The indicator can comprise a visual or audible indicator. Alternatively, the presence of improperly printed documents can be determined in other manners. For example, a plurality of document receivers could be provided such that one document receiver receives properly printed documents while a separate document receiver receives improperly printed documents. While the printing of numbers has been disclosed, any type of printed information can be verified using the method and apparatus of the present invention. While printing in different colors has been disclosed, printing can be performed in different shades of one color.

It is thus evident that many alternatives, modifications and verifications will be apparent to those skilled in the art. Accordingly, the preferred embodiment of the invention as set forth herein is intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the invention as defined in the following claims.