DOCSLIB.ORG

Laser Wirephoto System

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Laser Wirephoto System Wireless World, June 1974 183 Laser wirephoto system A report on the design and development of a wirephoto transceiver to be used by Associated Press news agency As part of the trend towards more efficient usage of telephone links, telephone companies are encouraging a changeover from high quality analogue lines to digital links. Professor W. Schreiber of Massachusetts Institute of Technology has developed a wirephoto transmitter- receiver and digital picture processor which meets this requirement. A method of transmitting colour pictures Of the types of photosensitive papers modulation. Processing to a digital form is over telephone lines has been recently available, dry silver paper seemed to be accomplished by a separate analogue-to- described in Wireless World.' However, most suited since it was capable of pro- digital converter contained within a signal although the processing of colour pictures ducing pictures of the desired quality and processing computer to be described later. was novel, the basic mechanism of the uses a very simple heat treatment for Better resolution and higher scanning transmitter; receiver and the continuing use picture development. The scanner/writer speeds are possible where other appli- of analogue signals over the telephone selected was a low -power helium -neon cations are considered. link were fairly conventional. The limita- laser, for the basic reason that it was Since the tone scale of the output pic- tions of such techniques are becoming reliable, cheap and, since it could be ture was considered to be the most impor- more obvious with time since the necessary directly modulated, eliminated the need tant single aspect of picture quality, control high quality audio links (800Hz to 18kHz for a separate modulator. Feedback control of the tone scale was provided by ensuring for the colour transmitter) are expensive of the laser brightness also achieves a con- stable processing of the exposed paper. In to establish and maintain. sistent control of the paper exposure. From addition a locally generated step wedge It would seem that the new digital links this starting point, several subsequent is printed at the beginning of every picture being offered by telephone companies are development decisions are possible con- and a non -linear amplifier operates on the a solution to some of these problems, cerning the method of scanning. Those receiver input signal to produce the since no special alignment is necessary to selected were a flat -bed scanner offering a required photo transfer characteristic. accommodate extreme bandwidth, making simple, low -cost paper drive, a galvano- it possible to provide temporary service meter- driven mirror for horizontal scan- The optical system over the ordinary local telephone distri- ning, continuous paper motion for vertical The optical system is based on a 1mW bution network, quickly and at low cost. scanning and oven processing of the modulatable He -Ne laser. The power out- With the increasing' availability of digital paper. put is more than adequate to expose the wired links, the digital encoding of picture The final system designed for use by 3M type 7771 dry silver paper, the only information makes economi; sense. Quite newspaper agencies handles both the in- disadvantage being that the spectrum of recently the American news agency put photographs and output paper as a light is such that a panchromatic paper is Associated Press commissioned a develop- continuous web, I lin wide and of any required, resulting in the need to expose ment project for a new telephoto trans- length. The scanning density is 1001ines per and process in darkness. Colour picture mitter /receiver and digital picture processor inch, per minute and to meet existing transmission would require an alternative which would meet the needs 'of the future. telephoto transmission standards the trans- light source. The laser selected is cheap This project was assigned to the Electronics mission signal is double-sideband amplitude and already in commercial production. A Research Laboratory of the Massachusetts Institute of Technology and was directed by Professor William F. Schreiber. The results of his work was the laser scanning, dry silver facsimile system and a separate beam digital picture described below expansion processor lens and in two papers published by MIT. 2'3 Selection of scanning/writing system galvanometer In developing a new facsimile machine advantage could be taken of the opportun- scanned ity to seek ways of improving the picture line quality over existing systems. Since the transmitter more often than not scans a horizontal continuous tone photograph, there is a deflection natural to a mirror tendency choose photo- focusing sensitive writing process. An additional lens advantage of such a choice is that the scanning and writing systems may be made to perform the dual function. Fig. 1. Mechanical layout ofthe optical scanner. .
Load more

Recommended publications
  • The Great Telecom Meltdown for a Listing of Recent Titles in the Artech House Telecommunications Library, Turn to the Back of This Book
    The Great Telecom Meltdown For a listing of recent titles in the Artech House Telecommunications Library, turn to the back of this book. The Great Telecom Meltdown Fred R. Goldstein a r techhouse. com Library of Congress Cataloging-in-Publication Data A catalog record for this book is available from the U.S. Library of Congress. British Library Cataloguing in Publication Data Goldstein, Fred R. The great telecom meltdown.—(Artech House telecommunications Library) 1. Telecommunication—History 2. Telecommunciation—Technological innovations— History 3. Telecommunication—Finance—History I. Title 384’.09 ISBN 1-58053-939-4 Cover design by Leslie Genser © 2005 ARTECH HOUSE, INC. 685 Canton Street Norwood, MA 02062 All rights reserved. Printed and bound in the United States of America. No part of this book may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without permission in writing from the publisher. All terms mentioned in this book that are known to be trademarks or service marks have been appropriately capitalized. Artech House cannot attest to the accuracy of this information. Use of a term in this book should not be regarded as affecting the validity of any trademark or service mark. International Standard Book Number: 1-58053-939-4 10987654321 Contents ix Hybrid Fiber-Coax (HFC) Gave Cable Providers an Advantage on “Triple Play” 122 RBOCs Took the Threat Seriously 123 Hybrid Fiber-Coax Is Developed 123 Cable Modems
    [Show full text]
  • Warren Commission, Volume XXII: CE 1407
    UNITED STATES DEPARTMENT OF JUSTICE FEDERAL BUREAU OF INVESTIGATION r,R.Frr.PL.. .Rd* . Dallas, Texas Ree ASSASSINATION OF PRESIDENT' F~ N. June 5, 1964 JOHN FITZGERALD KENNEDY, NOVPMEFR 22, 1963, D&LIAr, TEXAS ASSASSINATION OF PRESIDENT On June 2,' 1964, JAMES W. ALTGENS . 6441 Pemberton JOHN FITZGERALD KENNEDY, Drive, telephone number EMerson 8-7766, Dallas, Texas, advised NOVEMBER 22, 1963, DALLAS, TEXAS he is employed as a wirephoto operator - photographer by Associated Press, Room 353, Dallas News Building, Dallas, In the May 24, 1964, issue of the "New York Herald Texas . ALTGENS said he sometimes acts in the capacity of the Tribune", Magazine Section, there appeared an article by DOM News Photo Editor . He said he has been employed by the BONAFEDE captioned "The Picture With a Life Of Its Own ." Associated Press for 26 years . ALTGENS advised he was born This article refers to the controversial Associated Press April 28, 1919, at Dallas, Texas . photograph of the Presidential motorcade wherein an individual resembling LEE HARVEY OSWLD appears in the doorway of the ALTGENS advised that on November 22, 1963, he was Texas School Book Depository . Previous investigation has assigned by Associated Press to take up a position along the identified this individual as BILLY NOLAN LOVELADY . This motorcade route for the purpose of obtaining pictures of the article reflects that J . W . ALTGENS, a veteran Associated President and the Presidential motorcade . ALTGENS related he Press photographer in Dallas, Texas, recalled shooting the left his office at 11 :15 A .M . and proceeded to the triple picture . The article further cemented that ALTGENS had never overpass above Elm and Main Streets where he intended to take been questioned by the FBI .
    [Show full text]
  • The Failure of Fax: When a Vision Is Not Enough
    The Failure of Fax: When a Vision Is Not Enough Jonathan Coopersmith TexasA&M University In the lastdecade, fax machineshave revolutionized communications. We have becomeused to and dependentupon instantaneousinformation. Many peoplecannot conceive how theyworked without a fax machine.The question, however,arises: If the conceptis so good,why did nearlya centuryand a half elapsefrom the first patent in 1843 until rapid commercialdiffusion in the 1980s? In actuality,attempts to commercializefacsimile technology extend back to the 1860s[5]. Its promotersspanned the spectrumfrom individualinventors, suchas Thomas Edison and Arthur Korn, to massivecorporations, such as Xerox and AT&T. Their most common feature until the mid-1980s was failure. The few successesoccurred not in generalcommunications but in dedicatedniche marketsand, evenhere, failuresflourished. Perhaps the questionshould be: In view of the dismalhistory of failures,why did so manypeople and companies pressahead? What motivatedindividuals and ill-msto commitresources to createnew marketsand technology,given the dauntinghistory that lay behind them? Failure,the lack of technicaland commercial success for a productin the marketplace,is endemicto innovativetechnologies. Failure is worthyof study if only to betterunderstand success. Historians of businessand technology acceptthis, but tend to focusmore on success. This lack of coveragedistorts our knowledgeof the businessprocess because failure is an integral,if not dominant, theme in the existenceof companies. Much scholarlywriting
    [Show full text]
  • City of Light: the Story of Fiber Optics
    City of Light: The Story of Fiber Optics JEFF HECHT OXFORD UNIVERSITY PRESS City of Light THE SLOAN TECHNOLOGY SERIES Dark Sun: The Making of the Hydrogen Bomb Richard Rhodes Dream Reaper: The Story of an Old-Fashioned Inventor in the High-Stakes World of Modern Agriculture Craig Canine Turbulent Skies: The History of Commercial Aviation Thomas A. Heppenheimer Tube: The Invention of Television David E. Fisher and Marshall Jon Fisher The Invention that Changed the World: How a Small Group of Radar Pioneers Won the Second World War and Launched a Technological Revolution Robert Buderi Computer: A History of the Information Machine Martin Campbell-Kelly and William Aspray Naked to the Bone: Medical Imaging in the Twentieth Century Bettyann Kevles A Commotion in the Blood: A Century of Using the Immune System to Battle Cancer and Other Diseases Stephen S. Hall Beyond Engineering: How Society Shapes Technology Robert Pool The One Best Way: Frederick Winslow Taylor and the Enigma of Efficiency Robert Kanigel Crystal Fire: The Birth of the Information Age Michael Riordan and Lillian Hoddesen Insisting on the Impossible: The Life of Edwin Land, Inventor of Instant Photography Victor McElheny City of Light: The Story of Fiber Optics Jeff Hecht Visions of Technology: A Century of Provocative Readings edited by Richard Rhodes Last Big Cookie Gary Dorsey (forthcoming) City of Light The Story of Fiber Optics JEFF HECHT 1 3 Oxford New York Auckland Bangkok Buenos Aires Cape Town Chennai Dar es Salaam Delhi Hong Kong Istanbul Karachi Kolkata Kuala Lumpur Madrid Melbourne Mexico City Mumbai Nairobi Sa˜o Paulo Shanghai Taipei Tokyo Toronto Copyright ᭧ 1999 by Jeff Hecht Published by Oxford University Press, Inc.
    [Show full text]
  • The Photographs of Frederick Sommer
    DATE: August 24, 2005 FOR IMMEDIATE RELEASE GETTY EXHIBITION SURVEYS RISE OF MODERN PHOTOJOURNALISM WITH NEWS-MAKING IMAGES FROM THE 1940s TO THE 1970s Pictures for the Press At the Getty Center, September 20, 2005–January 22, 2006 LOS ANGELES—Many of the news-making events of the 20th century were documented by photojournalists, whose images helped to tell the stories of events that shaped our world. Pictures for the Press, at the Getty Center, September 20, 2005–January 22, 2006, presents a selection of memorable news images from the 1940s to the 1970s, depicting war, politics, and the civil rights struggle. Featuring many recent acquisitions, the exhibition examines the role of photojournalists in the recording of history and the way pictures are used by the press for making news. Newly acquired works by well-known press photographers like Robert Capa, Larry Burrows, and Charles Moore are included alongside pictures by lesser-known and, in some cases, unidentified makers. Pictures for the Press will feature about 35 photographs drawn from the Getty Museum’s growing collection of photojournalism. Acquired from a variety of sources, including the archives of The New York Times, many of the works on view were originally reproduced in newspapers or magazines and bear the stamps, captions, airbrushing, and worn quality typical of frequently handled archival documents. They include the actual prints used by the New York Times to reproduce images of the atomic explosion over Nagasaki and of the evacuation of Saigon 30 years ago. The exhibition also includes iconic images of the D-Day invasion of Omaha Beach during -more- Page 2 World War II, the assassinations of President Kennedy and Lee Harvey Oswald, and civil rights demonstrations in Birmingham, Alabama during the 1960s.
    [Show full text]
  • (Iowa City, Iowa), 1968-09-17
    , ~ ail Iowan Plan Advanced Ser in,e the Unicer. ily of 101m alii! the People of Iowa City To Hobble Court Established in 1868 10 cenla a copy ~ Associated Press Leased Wire and Wirephoto Iowa City, Iowa 52240-Tuesda)l, September 17, 1961 Toledo CoIL ' Dirksen Proposes Barring Justices Te~ Xavier Par_ Morehead From Ruling on Obscenity Cases Colorado Teachers Turn Down Peace Plan WASHINGTON 111- The ftabt over Abe Bart, in a letter to the committee chair­ and Cali. 1'1':'tu' nomIDatloa u chief juatlee took man, Sell. James O. EutlaDd CD-Mia,), at Texas. N.Y.C. Schools a urprise tum Monday wben Sftl. Ever· said it would be Improper for him tD taU­ ttt M. Dirksen (R-W.l offered leglalaUon fy. Pierson. In a similar letter, said he to bar the Supreme Court [rom overturn· could not appear .. a matter 01 principle ing obtctnity convictiOlll. aDd precedents." To Stay Closed DIrben, the Senale GOP leader, pro­ A a result, the committee did not ex­ pand on testimony by Sen. Gordon AlIDtt NEW YORK (All - A peace formula posed the meuun! u an amendment to aimed at reopenlng classrooms for 1.1 gun-contrDI legislation IIIIW before the Sen· (R-Colo,) that Fortas had "cleared" legis. million New York public school children ate. lation to extend Secret Service protection was turned down Monday by a striking 1ajority leader Mike Mansfield (J). to pre identlal and vice presidcntial can· teachers' union. ManU Immediac.ely endoreed Dlrksen'a didates. move. Manafield aaid that Conueae ought AUott, who plans to vote against Fort· Albert Shanker, president of the AFt,.
    [Show full text]
  • 2006 SPIE Invited Paper: a Brief History of 'Pixel'
    REPRINT — author contact: <[email protected]> A Brief History of ‘Pixel’ Richard F. Lyon Foveon Inc., 2820 San Tomas Expressway, Santa Clara CA 95051 ABSTRACT The term pixel, for picture element, was first published in two different SPIE Proceedings in 1965, in articles by Fred C. Billingsley of Caltech’s Jet Propulsion Laboratory. The alternative pel was published by William F. Schreiber of MIT in the Proceedings of the IEEE in 1967. Both pixel and pel were propagated within the image processing and video coding field for more than a decade before they appeared in textbooks in the late 1970s. Subsequently, pixel has become ubiquitous in the fields of computer graphics, displays, printers, scanners, cameras, and related technologies, with a variety of sometimes conflicting meanings. Reprint — Paper EI 6069-1 Digital Photography II — Invited Paper IS&T/SPIE Symposium on Electronic Imaging 15–19 January 2006, San Jose, California, USA Copyright 2006 SPIE and IS&T. This paper has been published in Digital Photography II, IS&T/SPIE Symposium on Electronic Imaging, 15–19 January 2006, San Jose, California, USA, and is made available as an electronic reprint with permission of SPIE and IS&T. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited. A Brief History of ‘Pixel’ Richard F. Lyon Foveon Inc., 2820 San Tomas Expressway, Santa Clara CA 95051 ABSTRACT The term pixel, for picture element, was first published in two different SPIE Proceedings in 1965, in articles by Fred C.
    [Show full text]
  • OPEN EVERY NIGHH the Change of Headquarters—The Third in the A
    Associated Press Offices Moved to New Building Nerve Center of Huge News Network Shifted To Rockefeller Center P> the Associated Press. NEW YORK, Dec. 17.—1The gen- eral offices of the Associated Press, nerve center of Its 285,000-mile net- work of leased news wires, moved tonight to the new 15-story Asso- ciated Press Building In Rockefeller Center. OPEN EVERY NIGHH The change of headquarters—the third in the A. P.’s modern life—pre- sented a major operation of herculean proportions, but service to its 1.350 newspaper members was not interrupted. News and wirephotos continued to move without interruption and all of the auxiliary services of the largest news service in the world functioned as usual. As the seventh and latest unit in the multimlllion-dollar skyscraper group of midtown Fifth avenue, the Plaid Blanket A. P. Building epitomizes the motif Comforts All colors. Not less Oil of speed in modern communication. $1 * 70x80-inch than rayon 80.98 The new site is four blocks north 5% wool. Double B taffeta. Five lovely ^ end two blocks west from the build- thickness. color combinations. ing at 383 Madison avenue, where since 1923 the A. P. has carried on the gigantic task of collecting and i redistributing news from all over the world. Timing Essential. But distance. In this case, was secondary to timing. The switchover of an elaborate maze of telegraph and telephone wires, wirephoto equipment, bat- teries of automatic speed printers, typewriters, desks and heavily- laden reference flies was timed for completion within nine hours—a procedure requiring perfect syn- chronization.
    [Show full text]
  • Television News Practices in Missouri
    UNIVERSITY OF MISSOURI BULLETIN VOLUME 56, NUMBER 31 JOURNALISM SERIES 1955, NUMBER 135 TELEVISION NEWS PRACTICES IN MISSOURI By Samuel Brownstein KHQA-TV KTTS-TV KSD-TV WDAF-TV KWK-TV KMBC-TV KOMU-TV KCMO-TV KDRO-TV KFEQ-TV KYTV Published by the University of Missouri at Room 102, Building T-3, Columbia, Missouri. Entered as second-class matter, January 2, 1914, at post office at Columbia, Missouri, under Act of Congress of August 24, 1912. Issued four times monthy October through May, three times monthly June through September.-1,000 SEPTEMBER 10, 1955 ACKNOWLEDGMENT While the responsibility for this study rests completely with the writer, many other persons contributed materi­ ally to its completion. Personnel at all the television stations included in this study were most cooperative and de­ serve sincere thanks for their assist- ance. A debt of gratitude also is owed Mr. Jean Madden, who copyread the origin­ al thesis; Dr. Edward C. Lambert, who patiently guided the study; and Dr. Earl F. English, Dean of the School of Journalism, who made publication possible. By Samuel Brownstein This is an abbreviated report of a study made of the methods used by eleven Missouri television stations to collect and present the news. The data were collected between June 7 and October 10, 1954, and con­ cern all stations which were operating on Missouri grants on July 12, 1954. Emphasis was placed on news programs which were originated by the individual television stations. This included general news, farm news, sports news, and weather news. At all or almost all of the stations investigated, this writer noted certain tendencies which he believes deserve particular mention.
    [Show full text]
  • Acronyms and Abbreviations*
    APPENDIX A Acronyms and Abbreviations* a atto (10-18) A ampere A angstrom AAR automatic alternate routing AARTS automatic audio remote test set AAS aeronautical advisory station AB asynchronous balanced (mode) (Link Layer OSI-RM) ABCA American, British, Canadian, Australian armies abs absolute ABS aeronautical broadcast station ABSBH average busy season busy hour ac alternating current AC absorption coefficient access charge access code ACA automatic circuit assurance ACC automatic callback calling ACCS associated common-channel signaling ACCUNET AT&T switched 56-kbps service ACD automatic call distributing automatic call distributor *Alphabetized letter by letter. Uppercase letters follow lowercase letters. All other symbols are ignored, including superscripts and subscripts. Numerals follow Z and Greek letters are at the very end. 1127 Appendix A 1128 ac-dc alternating-current direct-current (ringing) ACE automatic cross-connection equipment ACF/VTAM advanced communications facility (VT AM) ACK acknowledge character acknowledgement ACK/NAK acknowledgement/negative acknowledgement ACS airport control station asynchronous communications system ACSE association control service element ACTS advanced communications technology satellite ACU automatic calling unit AD addendum AID analog to digital A-D analog to digital ADAPT architectures design, analysis, and planning tool ADC analog-to-digital converter automatic digital control ADCCP Advanced Data Communications Control Procedure (ANSI) ADH automatic data handling ADP automatic data processing
    [Show full text]
  • AP Means Associated Press
    (AP) Means Associated Press: 166 Years of Logotype Design An exhibit marking the debut of a new AP logotype on view March 1, 2012 through August 15, 2012 at The Associated Press, New York City Exclusive. Truthful. Impartial. Non-partisan. Factual. With Utmost Speed The ligatured AP bug unleashed a stream of innovative variations. As the and Accuracy. These are a few of the ways AP described itself from the 1860s to organization grew and technology advanced after the war, news services in the early 1980s. During this period, AP had no official logotype or trademark, but text, photography, radio and eventually television proliferated. To market it was in no doubt as to its mission. A 1911 booklet, Instructions for Correspondents, these products, the Promotions Department (predecessor of Corporate solemnly declares: “The Associated Press is a mutual organization, of persons Communications) designed flyers, brochures, inserts, advertisements and representing daily newspapers, having for its sole purpose the collection and instructional booklets. Newsfeatures employed artists whose signed drawings distribution for its members of the important news of the world….” adorned the covers of AP World, the magazine written by and for AP staff. There was no consistency in typography or design but a good deal of verve. From the time its dispatches appeared in newspapers, AP was concerned they be correctly attributed. In the early 1920s, AP asked newspapers to simplify their In 1981, AP made its first trademark design application for “AP ASSOCIATED credit line by using a two-letter ligatured “bug” in parentheses after the dateline. PRESS.” This Helvetica mark was registered in 1983 and will be retired in 2012.
    [Show full text]
  • UC Santa Barbara Electronic Theses and Dissertations
    UC Santa Barbara UC Santa Barbara Electronic Theses and Dissertations Title Scanner Epistemologies: Mediations of the Material and Virtual Permalink https://escholarship.org/uc/item/5qp8v3zs Author Le, Lan Xuan Publication Date 2017 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California UNIVERSITY OF CALIFORNIA Santa Barbara Scanner Epistemologies: Mediations of the Material and Virtual A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Film & Media Studies by Lan Xuan Le Committee In Charge Professor Lisa Parks, Chair Professor Charles Wolfe Professor Greg Siegel Professor Rita Raley June 2017 The dissertation of Lan Xuan Le is approved. ______________________________________________ Charles Wolfe ______________________________________________ Greg Siegel ______________________________________________ Rita Raley ______________________________________________ Lisa Parks, Committee Chair June 2017 Scanner Epistemologies: Mediations of the Material and Virtual Copyright © 2017 by Lan Xuan Le iii ACKNOWLEDGMENTS I would like to thank my committee members for their support of my work. iv VITAE OF LAN XUAN LE June 2017 EDUCATION Bachelor of Arts in Biology and Asian Studies, Swarthmore College, 2004 Masters of Public Health, Boston University, 2007 Masters of Science in Comparative Media Studies, Massachusetts Institute of Technology, 2009 Doctor of Philosophy in Film & Media Studies, University of California, Santa Barbara, January 2017 (expected) PROFESSIONAL EMPLOYMENT 2010-2016: Teaching Assistant, Department of Film & Media Studies, University of California, Santa Barbara PUBLICATIONS Le, Lan X. 2016. “The Barcode Network: The Material of Informatics.” Convergence: the International Journal of Research into New Media Technologies. (In Review) Osterweil, S. & Le, L. X. 2010. “Learning and Change - A View from MIT’s Education Arcade.” Cognitive Technology Journal.
    [Show full text]