Bernard J. Lechner (January 25, 1932 – April 11, 2014) was an

electronics Electronics is a scientific and engineering discipline that studies and applies the principles of physics to design, create, and operate devices that manipulate electrons and other Electric charge, electrically charged particles. It is a subfield ...

engineer Engineers, as practitioners of engineering, are professionals who Invention, invent, design, build, maintain and test machines, complex systems, structures, gadgets and materials. They aim to fulfill functional objectives and requirements while ...

and formerly vice president,

RCA RCA Corporation was a major American electronics company, which was founded in 1919 as the Radio Corporation of America. It was initially a patent pool, patent trust owned by General Electric (GE), Westinghouse Electric Corporation, Westinghou ...

Laboratories, where he worked for 30 years covering various aspects of television and information display technologies.

Biography

Lechner was born in

New York City New York, often called New York City (NYC), is the most populous city in the United States, located at the southern tip of New York State on one of the world's largest natural harbors. The city comprises five boroughs, each coextensive w ...

, N.Y., in 1932. He grew up and attended high school in New Rochelle, New York. According to his ''oral history'' recollections, he was already very interested in radio and TV receivers during his high school years. He built sets with commercially available kits. Then, he studied electrical engineering at the

Columbia University Columbia University in the City of New York, commonly referred to as Columbia University, is a Private university, private Ivy League research university in New York City. Established in 1754 as King's College on the grounds of Trinity Churc ...

, interrupted by two years service for the U.S. Army Signal Corps in the US and Germany. He received the B.S.E.E. degree in 1957. In 1957, he joined the

RCA Laboratories RCA Corporation was a major American electronics company, which was founded in 1919 as the Radio Corporation of America. It was initially a patent trust owned by General Electric (GE), Westinghouse, AT&T Corporation and United Fruit Company ...

Princeton, New Jersey The Municipality of Princeton is a Borough (New Jersey), borough in Mercer County, New Jersey, United States. It was established on January 1, 2013, through the consolidation of the Borough of Princeton, New Jersey, Borough of Princeton and Pri ...

, as Member of Technical Staff and worked on various aspects of video engineering such as a home video tape recorder, two-way cable TV services (pay-TV and interactive shopping),

TV tuner A TV tuner card is a kind of television tuner that allows television signals to be received by a computer. Most TV tuners also function as video capture cards, allowing them to record television programs onto a hard disk much like the digital vi ...

s and TV broadcast cameras. He headed various RCA research groups working on these developments. While already working at RCA, he did graduate work at

Princeton University Princeton University is a private university, private Ivy League research university in Princeton, New Jersey, United States. Founded in 1746 in Elizabeth, New Jersey, Elizabeth as the College of New Jersey, Princeton is the List of Colonial ...

and at the Harvard School of Business. Bernie died on April 11, 2014.

Active matrix Active matrix is a type of addressing scheme used in flat panel displays. It is a method of switching individual elements of a flat panel display, known as pixels. Each pixel is attached to a transistor and capacitor that ''actively'' maintain th ...
addressing

George H. Heilmeier, who had joined the RCA Laboratories a year after Lechner, started working with

liquid crystals Liquid crystal (LC) is a state of matter whose properties are between those of conventional liquids and those of solid crystals. For example, a liquid crystal can flow like a liquid, but its molecules may be oriented in a common direction as i ...

in 1964. A team led by Heilmeier developed the first

liquid crystal display A liquid-crystal display (LCD) is a flat-panel display or other Electro-optic modulator, electronically modulated optical device that uses the light-modulating properties of liquid crystals combined with polarizers to display information. Liq ...

s (LCD). Lechner joined the efforts with the intention of applying LCDs to TV screens. For this purpose, Lechner's team studied simple matrix LCDs with a few lines and columns. It became obvious that there were tight limitations for the number of picture elements (

pixels In digital imaging, a pixel (abbreviated px), pel, or picture element is the smallest addressable element in a raster image, or the smallest addressable element in a dot matrix display device. In most digital display devices, pixels are the sma ...

) addressable by a direct-drive addressing scheme (

passive matrix addressing Passive matrix addressing is an Display addressing scheme, addressing scheme used in early liquid crystal displays, liquid crystal displays (LCDs). It is a matrix addressing scheme, meaning that only ''m'' + ''n'' control signals are requi ...

) due to the limited contrast and response speed. Lechner was first to apply a '' sample-and-hold'' technique to this type of display by connecting a capacitor in parallel with each LCD pixel and controlling its charge through a

field-effect transistor The field-effect transistor (FET) is a type of transistor that uses an electric field to control the current through a semiconductor. It comes in two types: junction FET (JFET) and metal-oxide-semiconductor FET (MOSFET). FETs have three termi ...

. Later-on, this technique was called active matrix addressing employing

thin-film transistor A thin-film transistor (TFT) is a special type of field-effect transistor (FET) where the transistor is made by thin film deposition. TFTs are grown on a supporting (but non-conducting) substrate, such as glass. This differs from the convention ...

s (TFT). It helped, that the semiconductor operation of RCA was among the leaders of MOS-FET developments ( CMOS 4000 series). At a press conference at RCA Headquarters in New York, a demonstration of such an LC matrix display with 36 pixels, using discrete components, took place in 1968 and showed the feasibility of the concept for TV panels. A corresponding publication followed in 1969. RCA reduced the efforts on LCDs and sold the remaining operations in 1976. Lechner concentrated his work on advanced video systems. He became RCA staff vice president for these activities. In this capacity he was a member of the US delegation to the ''Comité Consultatif International pour la Radio'' (CCIR, now

ITU-R The ITU Radiocommunication Sector (ITU-R) is one of the three sectors (divisions or units) of the International Telecommunication Union (ITU) and is responsible for radio communications. Its role is to manage the international radio-frequenc ...

) in Geneva for a new

HDTV High-definition television (HDTV) describes a television or video system which provides a substantially higher image resolution than the previous generation of technologies. The term has been used since at least 1933; in more recent times, it ref ...

standard from 1989 to 1990.

Lechner distance

The Lechner Distance chart illustrates the optimal viewing distances at which the human eye can best process the details an HDTV resolution has to offer. For example, the optimal viewing distance for a Full HD TV (1080p) is . Lechner researched the typical distance between a viewer and their television screen by taking measurements in many American homes. The median distance compiled from all his data came out to . Given this distance, a Full HD TV (1080p) with a screen size of would deliver the optimal viewing resolution. When GE acquired RCA and gave the David Sarnoff Research Center to SRI International in 1987, Lechner took early retirement. Lechner continued his work as independent consultant serving on standard committees and in related organizations as well as an expert witness in patent cases.

Memberships and awards

Lechner was a Fellow of the

IEEE The Institute of Electrical and Electronics Engineers (IEEE) is an American 501(c)(3) organization, 501(c)(3) public charity professional organization for electrical engineering, electronics engineering, and other related disciplines. The IEEE ...

, the

Society for Information Display The Society for Information Display (SID) is an industry organization for displays, generally electronic displays such as televisions and computer monitors. SID was founded in September 1962. Its main activities are publishing technical journals ...

(SID) and the

Society of Motion Picture and Television Engineers The Society of Motion Picture and Television Engineers (SMPTE) (, rarely ), founded by Charles Francis Jenkins in 1916 as the Society of Motion Picture Engineers or SMPE, is a global professional association of engineers, technologists, and e ...

(SMPTE). He was a member of the

honor societies In the United States, an honor society is an organization that recognizes individuals who rank above a set standard in various domains such as academics, leadership, and other personal achievements, not all of which are based on ranking systems. ...

Tau Beta Pi The Tau Beta Pi Association (commonly Tau Beta Pi, , or TBP) is the oldest engineering honor society and the second oldest collegiate honor society in the United States. It honors engineering students in American universities who have shown a ...

, Eta Kappa Nu and

Sigma Xi Sigma Xi, The Scientific Research Honor Society () is an international non-profit honor society for scientists and engineers. Sigma Xi was founded at Cornell University by a faculty member and graduate students in 1886 and is one of the oldest ...

. In 1971, he was named the first recipient of the SID Frances Rice Darne Award for his outstanding contributions to matrix displays and in 1983, he was named the first recipient of the Beatrice Winner Award for his contributions to SID. He was awarded the David Sarnoff Medal in 1996 and the Progress Medal in 2001 by the

(SMPTE) for his many contributions to the technologies essential to today's television systems. Lechner received two RCA Laboratories Outstanding Achievement Awards and a David Sarnoff Team Award in Science. In 2000, the Advanced Television Systems Committee (ATSC) established the Bernard J. Lechner Award in his honor. In 2011, he received the

IEEE Jun-ichi Nishizawa Medal In 2002, the Institute of Electrical and Electronics Engineers (IEEE) added a new award to its already existing program of awards. Each year, one or more nominees are honored with a medal in the name of Jun-ichi Nishizawa, considered to be the ' ...

for conceiving the principle of active matrix LCDs ( AMLCD)

Selected publications

Lechner has widely published in the areas of displays and television systems. He also holds ten United States

patent A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an sufficiency of disclosure, enabling discl ...

s. * Lechner, B.J.: ''Testing HDTV terrestrial broadcasting systems'', IEEE Transactions on Broadcasting, Vol. 37 (1991), No. 4, pp. 148–151 * Kressel H. and Lechner, B. J. (guest editors): ''Scanning the issue-Special issue on consumer electronics'', Proc. IEEE, Vol. 82 (1994), No. 4, pp. 445–458 * Lechner, B.J.; Chernock, R.; Eyer, M.K.; Goldberg, A.; Goldman, M.S.: ''The ATSC Transport Layer, Including Program and System Information Protocol (PSIP)'', Proceedings of the IEEE, Vol. 94 (2006), No. 1, pp. 77–101 * Lechner, B.J.: Guest Editorial, ''It's a High-Definition World'', Information Display, Vol. 23, No. 11, November 2007 * Lechner, B.J.: ''History Crystallized: A First-Person Account of the Development of Matrix-Addressed LCDs for Television at RCA in the 1960s'', Information Display, Vol. 24, No. 1, January 2008

References

External links

TV Viewing Distance versus Screen Size

BBC R&D White Paper WHP092
''Tests of visual acuity to determine the resolution required of a television transmission system'', J.O. Drewery and R. Salmon, 2004. {{DEFAULTSORT:Lechner, Bernard J. American electrical engineers Fellows of the IEEE 1932 births 2014 deaths People from New Rochelle, New York Harvard John A. Paulson School of Engineering and Applied Sciences alumni Engineers from New York (state)