Basic Concepts Of Electronic Printing

1. Basic Concepts Of Electronic Printing William J. “Bill” McCalpin EDPP, CDIA, MIT, LIT The Xenos Group (972) 857-0776 Xplor Global Conference Los Angeles, CA 1999

2. About The Speaker • Mr. McCalpin is Director of Product Management at Xenos Group • He received the EDPP from Xplor International in 1992. • He received the CDIA from CompTIA in 1996. • He received the MIT from AIIM in 1997. • He received the LIT from AIIM in 1998.

3. About The Speaker (cont.) • Mr. McCalpin writes and speaks frequently on subjects in the electronic printing and imaging industries. He has spoken more than forty times at Xplor, AIIM, DocuGroup, and Guide meetings. • Mr. McCalpin is a member of both Xplor and AIIM. He serves on multiple committees in AIIM and Xplor.

4. A (Very Brief) History Of Printing

5. The Chinese • By the end of the 2nd century A.D., the Chinese had the three requirements for printing: • paper • ink • relief surfaces.

6. The Chinese (cont.) • By the 8th century, wooden blocks were used for the reliefs. The oldest known printed works date from this time • 764-770 - Buddhist incantations printed in Japan • 868 - The first known book was made in China, ‘The Diamond Sutra.”

7. The Chinese (cont.) • Movable type was invented in China in the 11th century, but this invention did not catch on. • In the early 14th century, a Chinese magistrate had a set of 60,000 Chinese characters carved on wooden blocks for the printing of a treatise on the history of technology.

8. The Arabs Bring Paper To The West • 8th century - The knowledge of how to make paper came through the caravan routes of Central Asia. • 12th century - Italians begin trading with the Arabs to bring paper to Europe. • 13th & 14th centuries - Europeans create papermaking centers in Italy, France, and Germany.

9. Europe Learned About Paper, But Not Printing Despite trade and the travels of people like Marco Polo, Europeans never learned the art of xylography (printing from wood carving) from the Chinese. The ability to print in this way was spontaneously learned by the Europeans no earlier than the last quarter of the 14th century.

10. The Europeans Start To Print • The first printed items were relief images pressed onto paper, typically religious in nature. • Text was added to the images, and so the first real books appeared in Europe in the first half of the 15th century.

11. Metallographic Printing 1430-1450 - After 12 centuries, Europeans finally go beyond the Chinese by making durable components for Metallographic printing: • the metal die • the matrix • cast lead

12. Johannes Gutenberg About 1450, Johannes Gutenberg first associated the idea of using die, matrix, and lead with the invention of the printing press.

13. The Screw Press The ‘screw press’ was used for the next 350 years with technological improvements allowing such a press to print up to 250 copies an hour.

14. Technology Improves Printing 19th Century The 19th century saw the introduction of: • stereotypy (stereotyped plates allow several presses to print the same text at the same time) • steam power • cylinder presses • roll-fed rotary presses • typecasting machines such as the Linotype and Monotype.

15. Technology Improves Printing 20th Century The 20th century introduced many more advance- ments in printing: offset printing, dry offset, color printing, photocomposition, even three dimensional printing.

16. At Last - Electronic Printing! • 1923 - Electrostatic printing was first demonstrated when the ink of a cylindrical typeform was attracted to paper by means of an electronic charge. • 1948 - two Americans conceived the idea of using a dry powder rather than ink, and the first modern office copiers were born.

17. The 9700 In 1977 or so, Xerox introduces the 9700, the first cut sheet production printer, and our industry starts to take off!

18. How Electronic Printers Print • Xerox Centralized Printers are white on black • HP and other printers are black on white

19. 1. The image is resolved into a bit map. 2. Each 'scan line' is dispatched to the engine. 3. A photoelectric drum which is on a circular belt is charged with a high voltage. 4. A laser is fired through a piece of glass at a rotating, mirrored polygon. 5. The bits in the scan line cause the piece of glass through which the laser is passing to vibrate. 6. The laser beam hits the drum for each ‘off’ pixel, and discharges that spot on the drum. How A Xerox 9700 Prints

20. 7. Toner is passed over the drum, and the toner sticks to the charged areas. 8. Paper is passed over the drum, and the toner now sticks to the paper. 9. The paper, now with toner applied, passes through a fuser, which is a set of very hot rollers (400°F) which ‘fuse’ the toner to the paper. 10. The paper is post-processed as needed and placed into an output bin. How A Xerox 9700 Prints (cont.)

21. Definitions In Electronic Printing Or, how what Gutenberg did five centuries still affects you today...

22. Type Type - from the Greek word typtein - to beat or strike. Even today, the phrase in Italian for ‘to type’ is battere a macchina, literally, to ‘beat with the machine’.

23. Resources • Font • Forms • Image • Graphic • Logo

24. Please Note • In AFP, a graphic refers only to a vector representation. • In AFP, an image refers only to a raster representation. • The word logo is a reference to a Xerox-specific object. • In AFP, a form is called an overlay.

25. Point Pica Pitch Monopitch Proportional x-height em space en space Measurements

26. 996 points are equivalent to 35 centimeters, or one point is equal to .01383 inches. This means about 72.3 points to the inch. We in electronic printing use 72 points per inch A Point

27. From the Medieval Latin word for directory, probably referring to the usual size of the type used to print a directory, about 1/6th of an inch; hence, 12 points make up a pica, and 6 picas make up an inch. A letter-sized sheet of paper in the U.S. is 66 picas long. Pica

28. The height of the lowercase x. Used in typography as the standard height of the body for all the characters in the font, minus their ascenders and descenders. b x p x-height

29. Originally, a unit of measure equal to the width of the capital M, the widest character in a font. Now the em space is equal to the height of the font, hence the em space of a 10 point font is 10 points (wide). The default word space for this font is 1/3 an em space. em

30. Half an em space. Two ens add up to an em. en

31. Probably from Middle English picchen, to strike - the number of characters per inch (applied to a monopitch font) Miwl Pitch

32. Referring to a font in which all the characters are the same width. Miwl 10 pitch is 10 characters per inch. Monopitch

33. Referring to a font in which each character has a width appropriate to the size of the character. E.g., in a proportional font (like this one), ‘I’ is much narrower than ‘W”. Miwl the ‘M’ is many times wider than the ‘i’ in a proportional font. Proportional

34. The Character • Raster fonts are fonts whose characters are defined by bitmaps (see right). • Outline fonts (also called scalable) are fonts whose characters are defined by strokes.

35. Character Anatomy

36. Baseline Baseline - An imaginary line upon which the body of the character sits. All characters on a line of text share the same baseline, even characters in different fonts.

37. Ascender - strokes which rise above the x-height (or body of the character). Descender - strokes which go below the baseline (or the body of the character). b q Ascender And Descender

38. Font height - the sum of the length of the longest descender, longest ascender, and x-height. Line skip - Usually, the distance from baseline to baseline. Note, this value is often larger than the font height. bxpW pxbM Font Height And Baseline

39. Kern - from the French word carne, meaning projecting angle or hinge, ultimately from the Latin word cardo (cardinis), a hinge. Kern is that part of the face of a letter which projects beyond the body. Kern

40. · Serif & Sans Serif - serif (also spelled cerif) comes from the Dutch word schreef, meaning a stroke or a line, from schrijve (to write, cf. German schreiben), ultimately from Latin scribere Serif Sans Serif Serif And Sans Serif

41. Leading - blank dies made of the metal lead were inserted between characters on a line of type to enable justifying the line of text to fit the print area This text has been left and right justified so the word spaces vary. Leading

42. Upper Case And Lower Case • The box on the right hand side contained individual pieces of type • The less frequently used characters would be at the top - away from the printer • Hence, capital letters were called “upper case”

43. Mind Your P’s And Q’s • “p’s and q’s” - the phrase mind your p’s and q’s comes from the days of metal type. On metal type, the image of the character is backwards from the printed image. Since a ‘p’ and a ‘q’ are mirror images of each other, it is easy to confuse them, hence the warning.

44. The Family Tree of Printer Data Streams

45. Philology • Philology is the study of language, normally human languages • One field of study in philology is the relationship that different languages have to one another • What happens if we apply philology to electronic printing?

46. The Family Tree

47. In The Beginning • The first computer created tables for artillery • Mechanical typewriters • ‘Line Data’

48. EBCDIC Versus ASCII • BCD - Binary Coded Decimal • BCDIC - Binary Coded Decimal Interchange Code • EBCDIC - IBM Extended Binary Coded Decimal Interchange Code • ASCII - American Standard Code for Information Interchange

49. EBCDIC Line Data • EBCDIC encoded - 8 bit • Record-oriented because of IBM OS’s • Carriage controls • Machine carriage controls • ANSI carriage controls

50. ASCII Line Data • ASCII encoded - 7 bit • ‘Record’ orientation is not intrinsic to OS • Text files use print controls to delimit records • Common print controls • x’0d’ carriage return • x’0a’ line feed • x’0c’ form feed