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HAROLD B 1911-1984 . LAW BY HUMBOLDT W. LEVERENZ HAROLD B LAW the inventor ant! developer of methods and structures for making vicleo crevices that are now used woric~wide, especially for television, cried on April 6, 1984, at the age seventy-two. He retired from RCA in 1976 as direc- tor of its Electronic Components, Materials, and Display De- vice Laboratory. In his retirement, he clevoted himself to farming his acreage near Hopewell, New Jersey, and took ag- ricultural courses to enhance his proficiency. He ctied sud- denly in the "sadctle" of his tractor. Law conceived and applied the methoc! of using light to simulate electronic beams for printing phosphor screens in color picture tubes for television and computers anct for mul- ticolor displays used in many other cievices. An earlier achievement was his method for making the delicate glass/ mesh target required for image orthicon camera tubes; the method included a technique for making very fine high- transmission metal meshes from a ruled glass master. Harold Law was an active, quiet, kindly man, who ~le- lighted in helping those he knew and in benefiting countless others through his inventions. Whether seater} or afoot, he always looked as though he was thinking - mainly because he was thinking. He was born on September 7, 1911, in the small town of Doucis in southeast Iowa, where his father taught school ant! 243

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244 MEMORIAL TRIBUTES had a small farm. The family moved to Kent, Ohio, around 1914, but Law returned during the summers to his grancI- father's farm, where he enjoyed doing the chores. In high school he applies! himself to school subjects, man- ual arts, band, and sports, as well as such extracurricular ac- tivities as building and flying gliders. After some gliding practice, he persuacled a local airplane pilot to teach him to fly a power plane lessons that included a solo flight in one morning. Law financed his undergraduate years at Kent State Uni- - . . . . . . versity by working six hours a night; he graduated in 1934 with a B.S. in liberal arts and another in education. After teaching mathematics for a year in Maple Heights, Ohio, he entered graduate school at Ohio State University and re- ceivecl his M.S. in physics in 1936. He again taught mathe- matics, this time for two years, and then returned to Ohio State, receiving his Ph.D. in physics in 1941. During his graduate work, Harold read an article about RCAs research on electron multipliers, and he attempted to duplicate some of the reported results. After he graduatect, he applied for a position in RCA,s research division in Cam- den, New Jersey, and began work there in Tune 1941. He was assigned to a group that was trying to make more sensitive electron emitter surfaces and to use electron multipliers in camera tubes. He found that he liked designing, fabricating, and testing experimental electron devices because, as he said, "it suited my do-it-yourself nature." When RCA consolidated its research in new buildings near Princeton, New jersey, in 1942, the newly married Law moved there and became part of a group whose task was to develop the image orthicon tube invented by Albert Rose. Rose guided the overall effort; Law worked on the second- ary-electron-emitting target (a very thin sheet of special glass mounted a few microns from a very fine mesh metal screen); and Paul K. Weimer worked on the electron multiplier and the electron optics of the scanning beam. Ideally, the image orthicon could have a thousand times

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HAROLD B. LAW 245 the sensitivity of the iconoscope, but the techniques and ma- terials needed to make the tube with the required precision were not available. Law attacked the target problems with his hands-on, "mincI-on" vigor and serendipity. Out of his ef- forts evolved the technique of using a fine diamond point to rule grooves on a glass plate. This step was followed by evap- orating platinum to a thin film over the plate and then rub- bing off the surface film. The platinum left in the grooves was electroplated with copper and pulled out intact; it was then welcled to a frame and heater! to about 500C, at which point the screen was pulled flat by internal cohesion, as man- ifested by surface tension. Rose stated: "This remains the classic way of making fine mesh ~ ~ ,000 lines/inch) screens, highly transparent (80% open area), and highly uniform." Yet the heating-to-tauter technique was so unusual that the patent examiner saici that it could not work because it was well known that metal ex- pands when heated. Law took heating equipment, frame, and mesh to the Appeals Board in Washington to demon- strate the efficacy of the procedure. Harold Law also made the thin, uniform glass emitter tar- get by heating it to temperatures high enough for cohesion to pull it flat. After the Law-Rose-Weimer team achieved practical image orthicons, they attendee! the first public dem- onstration by RCA in which it was shown that the tube could give a television picture of a young woman's face illuminatec! by the light from a single match. The image orthicon was the acme of the photoemitter-type camera tubes and was in com- mercial use for many years. After World War II, major efforts were initiated to develop color television. The approach advocated by RCA was to pro- vide a compatible color system that is, one whose pictures could be seen in color on new color sets and in monochrome on existing black-and-white sets. The RCA concept was deemed to be impossible by many because it needect pioneer- ing inventions of systems, circuits, devices, and the methods for making them. RCA engineers devised many potential so-

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246 MEMORIAL TRIBUTES lutions from which the few practical ones tract to be chosen, clevelopect, and demonstrated under time pressures that had been imposed during hearings held by the Federal Commu- nications Commission, which favored stanciarctizing a non- compatible color system. A key part of the "sought-for" compatible color television was a device to reproduce the color picture, a solution that was then unknown. In September 1949, a special meeting was called at RCA Laboratories, which was attended by Har- old Law ant! other selected members of the technical stab. Those present were invited to participate in a three-month "crash program" to demonstrate the feasibility of a color pic- ture tube. Overall organization ant! coordination of the ef- fort were assignee! to Edward W. Herold. Law welcomed the challenge anc! recalled some experi- ments he had done "on the si(le" to make color phosphor screens in patterns by using a photographic process. He chose to use a form of three-electron-beam, three-phosphor- element color kinescope invented! by Alfred C. Schroeder. In Schroeder's crevice the beams went through holes in a mask, each beam striking one array of phosphor clots emitting one color. In mulling over ant! experimenting with means to deposit the hundreds of thousands of phosphor dots in exactly the right spots, Saw conceived the idea of using a light source placed at the deflection center of one electron beam. The light source would shine through the mask apertures and strike a transparent plate coated with a photosensitive binder containing one of the phosphors, affixing the phosphor clots in those locations. The process wouIc! be repeated for the other two beams and colors. Law's invention, with flat masks and flat phosphor screens, was used to show the feasibility of the color kinescope within the three-month cleactline, and the RCA compatible color system eventually prevailed. An extension of Law's tech- nique, using curved masks and depositing the phosphor dots

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HAROLD B. LAW 247 on the curves! inside end of the kinescope, was announced by N. F. Fyler, W. E. Rowee, ant! C. W. Cain in 1954. The methoc! is still used to produce color picture tubes worIcI- wide. As might be expected, Law's important invention was con- testect, and the patent was not issues] until 1968. The turning point in the lengthy litigation came when Edward Herold gave cogent supporting testimony from his records as coor- clinator of the crash program and subsequent clevelopments. Harold Law was elected to membership in the National Acaclemy of Engineering in 1979, having previously been named a fellow of the Institute of Electrical ant! Electronics Engineers (IEEE) in 1955, a fellow of the Society of Infor- mation Display in ~ 97 I, and a fellow of the Technical Staff of RCA Laboratories. He was a also member of the American Physical Society and Sigma Xi. He received the Television Broadcasters Association Award (19461; the {EKE Zworykin Television Prize (19551; the Consumer Electronics Scientist of the Year Awarcl (19664; the IEEE I=amme Medal (1975~; and the Frances Rice Darne Memorial Awarct (1975~. From Kent State University, he received the Outstanding Graduate Citation (1959) and an honorary D.Sc. (1984~. RCA gave him five awards. His thirteen publications include "The Image Orthicon- A Sensitive TV Pickup Tube" (with A. Rose and P. K. Wei- mer), in Institute of Radio Engineers Proceedings, (vo! 34, July 19461; "A Technique for the Making and Mounting of Fine- Mesh Screens" in Review of Scientific Instruments (vo} 19, De- cember 19481; and "The Shaclow-Mask Color Picture Tube: How it Began" in JEER Transactions on Electron Devices (vo! ED-23, July 19761. Two of his "inventions," the method of making fine-mesh screens and photographic methods of making electron-sensitive mosaic screens, are particularly outstanding among his thirty-eight U.S. patents. Harold Law met his wife Ruth (nee Workman), a gifted mathematics teacher, through his sister, Mabel. He is sur- ,, ,

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248 MEMORIAL TRIBUTES vived by Ruth; their married daughters, Linda Krantz, Sara SchIenker, ant! Kathy OrIoski; six grandchildren; and his sis- ter, now Mabel Winters. He once told Ruth that he enjoyed] his work with RCA as much as his work on the farm. About the farm, he said, "Living on this place is as near to heaven as you can get."

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