CSA Z243 41-1980 Paper Used in Optical Character Recognition (OCR) Systems (First Edition).pdf

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1、ANSI X3.62-I 979 Revision of ANSI X3.17-1974 (Reaffi r med 2004) American National Standard for Paper Used in Optical Character Recognition (OCR) Systems Secretariat Computer and Business Equipment Manufacturers Association Approved November 16, 1978 American National Standards Institute, lnc Prefac

2、e to CSA standard 2243.41-1 980 OCR Paper This is the first edition of CSA Standard 2243.41, OCR Paper, and is a revision and expansion of the Guidelines for OCR Paper Requirements contained in Appendix E of CSA Standards 2243.224915, Style A Character Set for Optical Character Recognition; and 2243

3、.24-1975, Style B Character Set for Optical Character Recognition. ANSI Standard X3.62-1979, OCR Paper, was reviewed and adopted with the modifications listed. However, the document should be considered an interim and transitional Standard, using Imperial measure, and further modification may be exp

4、ected. CSA Standard 2243.41-1980, OCR Paper, was prepared by the CSA Technical committee on Character Recognition under the jurisdiction of the Standards Steering Committee on Computers, Information Processing and Office Machines and was formally approved by these Committees. Rexdale, January, 1980

5、Note: AZZ enquiries regarding this Standard shoutd be addressed to Cnadin Standards Association, 178 RexdaZe BouZevard, RexdaZe, Ontario M9W 1R3. CSA Standards me subject to periodical review and suggestions for their improvement will be directed to the appropriate committee. Requests for interpreta

6、tion will QZSO be accepted by the committee. They should be worded in such u manner CIS to permit a simple “yes“ or rrnff unswer based on the Ziteral text of the requirement concerned. Formal interpreta- tions are published in !TSA lnformtion Update“ (for subscription details and a free sample copy,

7、 write to CSA Information Central or teZephme (426) 744-4228). Technical Committee on Character Recqtion C.Y. Suen (Chairman) Concordia University, Montreal, Quebec R. Brown Moore Business Forms, Toronto, Ontario AmDm DW Ottawa, Ontario GJ. GRllRrrt Post Office Department, Ottawa, Ontario LmRm Horni

8、ng R.L. Crain Limited, Ottawa, Ontario DJm Hupp Recognition Equipment (Canada) Ltd., Markharn, Ontario R.C. Mafreux IBM Canada Ltd., Don Mills, Ontario D. Miller OCR Concepts Ltd., Rexdale, Ontario J. Tucker Control Data Canada Ltd., Montreal, Quebec E. Wand St. Catharines, Ontario J.L. Welch Dornta

9、r Fine Papers Limited, Cornwall, Ontario H.Z. Rogers (Secretary, Non-voting) Canadian Standards Association, Rexdale, Ontario In addition to the members of the Committee, the foZZowing made valuable contribution to the development of this Standard in their capacities as noted: C. Mi that is, the rec

10、eiver used for measurement shall exclude specularly reflected light. Reflectance measurements shall be re- ferred to the perfect reflecting diffuser (I 00% reflec- tance). However, in practice, barium sulfate ( BaS04) may be used with sufficient accuracy. In case of dis- agreement, the measurements

11、shall be based on the perfect reflecting diffuser. Paper reflectance measurements shall be made using the infioite pad method; that is, the samples being measured should be backed with a sufficient number of paper thicknesses of the same type of paper such that doubling the number will not change th

12、e measured value of reflectance. Reflectance may be determined either by means of spectrophotomet- ric measurements or by a number of reflectance measurements in different spectral bands. See Ameri- can National Standard Practice for Spectrophotometry and Description of Color in CIE 193 1 System, AN

13、SI/ ASTM E308-66 (R1974). 2.5.1.1 Visual Spectrum. The average reflectance of the paper shall be not less than 60% in the range from 425 nm (nanometers) to 500 nm, and shall be not less than 70% in the range from 500 nm to 700 nm. 2.5.1.2 Infrared Spectrum. When the near infra- red (IR) spectrum is

14、of interest, an average reflectance of 70% in the range from 700 nm to 1200 nm is re- quire d. 2.5.2 fluorescence. Fluorescence can adversely affect the reading or sorting capabilities, or both, of certain OCR systems. Therefore, fluorescent additives should not be used in OCR papers. It is recogniz

15、ed, however, that a certain degree of fluorescent contami- nation may be unavoidable in the papermaking process. For Type I and Type I1 OCR papers, fluorescent contamination should not result in more than a 2.0% difference in reflectance when measured with and with- out the ultraviolet component of

16、a light source of 3 100” Kelvin in combination with a CIE Z (blue) filter. For Type 111 OCR papers, fluorescence should not re- sult in more than a 5.0% difference in reflectance. (See Table A1 in the Appendix for a summary of OCR paper classifications.) 2.5.3 Paper Opacity (Reference TAPPI T425-m-6

17、0). Paper opacity is defined as the ratio of the diffuse re- flectance of a specimen backed with a black material of not more than 0.5% reflectance to the diffuse reflec- tance of the same specimen backed with a white body having an absolute reflectance of 89%. Opacity is indicative of the effect th

18、at backing mate- rial has on paper reflectance. If the paper transport sys- . tem of the OCR device is such that a known uniform highly reflective surface is provided at the time of read- ing, a medium opacity paper may be usable. However, some systems scan paper backed by other printing or have a t

19、ransport system that provides a nonuniform or low-reflectance backing surface. For such cases a high- opacity paper should be used. The minimum opacity required for an OCR paper will depend upon the OCR device used and the applica- tion. In general, opacity is related to the basis weight (see 2.6.1)

20、 of the paper; the higher the basis weight, the greater the opacity. In general, papers having opacity exceeding 85% should be used. Papers of lower opacity should be used only if needed for the application and after considering the optical system. Papers having opacity less than 65% should not be u

21、sed. Many inks have the property of permeating the paper to a considerable depth. Applications requiring printing on both sides may require a higher paper opacity to compensate for this effect. 1-5. appearance of a surface. It is a phenomenon related to the specular reflection of the incident light.

22、 The effect of gloss is to reflect more of the incident light in a specu- lar manner, and to scatter less. It occurs at all angles of incidence and should not be confused with grazing angle specular reflection that is often referred to as sheen. Paper gloss is undesirable for OCR systems since it af

23、- fects diffuse reflectance adversely, thus affecting the print contrast signal. Paper for OCR should be restricted to low-gToss varieties such as normally found in uncoated bonds, ledgers, index, journal tape, and tag and tabulating stock. 2.5.5 Dirt in Paper. Dirt in paper can be a critical factor

24、 in some OCR applications. As discussed in 2.4, two levels of dirt tolerance are recognized. Type I OCR papers would be required where there is a low tolerance to dirt. Type 11 or Type 111 OCR papers could be used where there is a higher dirt tolerance. It is recommended that concurrence of the OCR

25、equipment manufacturer be established before Type 11 or Type 111 OCR papers are used. Dirt is defined as relatively nonreflecting foreign particles embedded in the paper. Since the lack of re- flectance and the size of such particles may cause them to be mistaken for inked areas by an OCR reader, it

26、 is important that both their frequency and size be small. There are two primary methods for measuring dirt in general use in the United States; these are the dirt in paper method of TAPPI T437 ts-63 and the mark count method. In the TAPPI method, the area of the Typical OCR paper opacity values are

27、 given in Tables 2.5.4 Paper Gloss. Gloss is the lustrous or mirrorlike 7 AMERICAN NATIONAL STANDARD X3.62-1979 dirt is estimated in terms of equivalent black area and expressed in parts per million. Only those dirt specks having an equivalent black area of 0.000062 in2 (0.04 mm) or larger are consi

28、dered. The mark count method expresses dirt in terms of the average number of marks or embedded dirt specks per 1000 in2 (4452 cm) of paper. All visible imperfections exceeding 0.00001 6 in2 (0.01 mm2) in area are counted. Both of the above methods are subjective in that they rely on the vision of t

29、he person making the test. Differences in perception, eye fatigue, lighting conditions, and the care with which observations are made can greatly affect reproducibility when the measurements are made by different people. Controlled comparisons using the mark count method on identical samples have re

30、sulted in test errors of 200% to 300%.At the same time, it is felt that the minimum dirt size specified in the TAPPI procedure is too large for most OCR applications. Studies have shown that many OCR systems can detect marks much smaller than the 0.000062-in2 (0.04-mm2) mini- mum equivalent area spe

31、cified in the TAPPI procedure. Because of the lack of precision and reproducibility in measuring dirt of the appropriate size, dirt specifica- tions have not been included in the body of this stan- dard. Commonly quoted dirt requirements, however, have been included in the Appendix as a guide, When

32、more precise and reproducible dirt count methods are developed - preferably by instrumentation - the practi- cality of these requirements can be evaluated and appro- priate specification limits incorporated in this standard. 2.6 Physical Properties. Certain physical properties of paper, such as basi

33、s weight, caliper, smoothness, tear, porosity, and stiffness may be significant in OCR appli- cations. 2.6.1 Basis Weight. The commercial terminology for expressing the weight per unit area of paper has been basis weight, defined as the weight of a given size sheet in pounds per ream (usually 500 sh

34、eets). For OCR papers this is normally the weight in pounds of 500 17 X 22 in sheets. The metric system for weight per unit area, expressed aqrams per square meter (gram- mage), is now the preferred system for technical stan- dards. Acceptable test methods are given in TAPPl T410 os-68 and ASTM D646

35、-67. 2.6.2 Caliper. Caliper or thickness of paper is de- fined as the perpendicular distance between the two principal surfaces of the paper under prescribed con- ditions of pressure. Acceptable test methods are given in TAPPI T411 os-68 and ASTM D645-67. 2.6.3 Smoothness. Smoothness of paper is def

36、ined as the time required for a fixed volume of air to leak across the surface of a paper sample. It is recorded as the num- ber of cubic centimeters of air per minute flowing over one square inch of paper area, multiplied by ten. An acceptable test method is given in TAPPI Useful Method 2.6.4 Poros

37、ity. Porosity of paper is defined as the re- UM-5 1 8. sistance of paper to the passage of air under a specified pressure through the paper. It is reported as the average time in seconds required to displace 100 mL of air through a one-square-inch area of paper under a pressure of 4.88 in (1 2.4 cm)

38、 of water. Acceptable test methods are given in TAPPI T460 os-48 and ASTM D726-58, reapproved in 197 1. 2.6.5 Stiffness. Stiffness of paper is defined as the bending moment which the paper can withstand in both directions by deflecting a small weighted pendulum. (See individual manufacturers test pr

39、ocedures.) 2.6.6 Tearing Resistance. Tearing resistance is de- fined as the average force in grams required to tear a single sheet of paper after the tear has been started. Acceptable test methods are given in TAPPI T414 ts- 65 and ASTM D-689-62, reapproved in 1968. 2.7 Typical OCR Paper Characteris

40、tics. The typical OCR paper characteristics given in Tables 1 through 5 are directed to the use of documents in interchange applications. The selected values are a compromise to define a paper with adequate characteristics for manual handling, machine processing, printing, and encoding. The values g

41、iven in the tables are intended to serve only as a guide. With the differences in available pulps and. processing equipment in paper mills, it is possible that papers with somewhat different values in one or several tests might work satisfactorily on some OCR scanners. j The values shown in the tabl

42、es, therefore, indicate a range of data which from experience generally produces satisfactory results. Papers that have parameters differ- ing greatly from the typical OCR paper characteristics should be carefully checked for their suitability on the OCR scanner for which they are intended. 3. Refer

43、enced Standards ASTM D585-74, Sampling and Accepting a Single Lot of Paper, Paperboard, Fiberboard, or Related Product ASTM D645-67, Test for Thickness of Paper and Paper- board Standards referenced are available from their respective pub Technical Association of the Pulp and Paper Industry, America

44、n National Standards Institute, 1430 3roadway, American Society for Testing and Materials, 1916 Race Iisher s : 1 Dunwoody Park, Atlanta, Ga. 30341. New York, N.Y. 10018. Street, Philadelphia, Pa. 19103. 8 AMERICAN NATIONAL STANDARD X3.62-1979 ASTM D646-67, Test for Basis Weight of Paper and Paperbo

45、ard ASTM D685-73, Conditioning Paper and Paper Prod- ucts for Testing ASTM D689-62, reapproved 1968, Test for Internal Tearing Resistance of Paper ASTM D726-58, reapproved 1971, Tests for Resistance of Paper to Passage of Air American National Standard Practice for Spectropho- tometry and Descriptio

46、n of Color in CIE 193 1 System, ANSIlASTM E308-66 (R1974) TAPPI T400 os-75, Sampling and Accepting a Single Lot of Paper, Paperboard, Fiberboard, or Related Product TAPPI T402 os-70, Standard Conditioning and Testing Atmospheres for Paper, Board, Pulp Hand Sheets, and Related Products TAPPI T410 os-

47、68, Weight per Unit Area (Basis Weight or Substance) of Paper and Paperboard TAPPI T411 os-68, Thickness (Caliper) of Paper and Pap e r b oar d TAPPI T414 ts-65, Internal Tearing Resistance of Paper TAPPI T437 ts-63, Dirt in Paper and Paperboard TAPPI T460 os-75, Air Resistance of Paper TAPPI UM-518

48、, Useful Method, Smoothness of Paper (She ffiel d) 9 AMERICAN NATIONAL STANDARD X3.62-1979 Table 1 Typical OCR Paper Characteristics - Bonds and Ledgers” Property Values and Test Methods Used Stiffness, Tear, Opacity Smoothness$ Either Either Caliper, 5 Basis Weightt (Bausch (SheffieId) Porosity Dir

49、ection Direction No mind 500 Sheets Federal Stock Number 7530-181-8930. 10 AMERICAN NATIONAL STANDARD X3.62-1979 Table 3 Typical OCR Paper Characteristics - Index Stock* Property Values and Test Methods Used Stiffness, Tear, Opacity Smoothness $ Either Either Caliper, 0 Basis Weightt (Bausch (Sheffield) Porosity Direction Direction Nominal 500 Sheets & Lomb) (Gurley) (Taber) (Elmendor0 25-1/2 X 30-1/2 in Min Min Max Min Min Min Min Max 90 Ib (162.7 glrn) 92% 70 200 20 sec 4 g-cm 120 g 0.0065 in 0.0086 jn. 100 lb (180.8 g/m) 94% 70 20 0 20 sec 13 g-cm 140 g 0.0080 in 0.0098 i