David Lewis Spears

Professional Biography of David Lewis Spears 

David Lewis Spears was born in Belvidere, Illinois, on July 22, 1940. He graduated from Marengo Community High School, Marengo, IL, in 1958. In 1962, he received a B.A. degree from Monmouth College, Monmouth, IL, with majors in Physics and minors in Mathematics and Chemistry. He was initiated into Phi Eta Mu (freshman scholastic society) and Sigma Omicron Mu (Monmouth's Phi Beta Kappa equivalent). In 1964, he received the M.A. degree in Physics from Dartmouth College, Hanover, NH. His Masters thesis was a theoretical calculation of the bandstructure of diamond and zincblend crystals using tight-binding theory. He received a Ph.D. degree in Solid State Physics from Purdue University, West Lafayette, IN, in 1969. His PhD thesis work involved numerous optical probe studies of acoustoelectric domains in n-GaAs, resulting in 10 publications. He received the 1969 Lark-Horowitz Prize in Physics from the Purdue University Physics Department for the best Ph.D. thesis for that year. While at Purdue, he was initiated into the honorary physics fraternity, Sigma Pi Sigma, and the honorary science fraternity, Sigma Xi. 

Dr. Spears joined the Solid State Division of Lincoln Laboratory of Massachusetts Institute of Technology in Lexington, MA, on April 20, 1969 as a Staff Member in the Applied Physics Group, a 50-member group involved in electro-optical device research. The group name was later changed to Electro-optical Devices. In September 1984, he became the Assistant Group Leader. While at Lincoln Laboratory, Dr. Spears has measured acoustoelectric parameters in GaAs, developed a GaAs/LiNbO3 surface- acoustic-wave amplifier, measured high-frequency surface-acoustic-wave attenuation in GaAs, invented and developed X-ray lithography for replication of sub-micrometer patterns, developed low-loss infrared optical waveguides in CdTe and high-performance acoustooptic and electrooptic waveguide modulators in those CdTe waveguides and contributed to the design of a 4-bit 1-Gsample/s guided-wave optical A/D converter in LiNbO3. He pioneered the field of wideband HgCdTe infrared photomixers, developing such devices as gigahertz-bandwidth quadrantal and 12-element photodiode arrays and thermoelectrically cooled photoconductors for use in Lincoln Laboratory's CO2 laser radar systems, and 28-um photodiodes and photoconductors for use in heterodyne radiometry. He has authored over 50 papers on infrared detectors and detector applications. In 1986, he received two best paper awards for presentations at the 1985 Meeting of IRIS Specialty Group on Infrared Detectors and the 1985 Meeting of the IRIS Specialty Group on Active Systems. In 1983, Dr. Spears served on an Ad Hoc Committee of the Air Force Scientific Advisory Board to Assess Approaches to Space- Based Missile Warning Systems. During 1983-85, he served as chairman of the Optical Sensors Technical Group of the Optical Society of America. In 1992, he was the recipient of a Laurels Award in Electronics from Aviation Week and Aerospace Technology Magazine. In 1994, he was made a Senior Member of the Institute of 

Electrical and Electronic Engineers (IEEE). He was also a member of the American Physical Society and the Society of Photo-optical Instrumentation Engineers (SPIE). In 1992, he became Assistant Leader of the Electronic Materials Group, a 25-member group developing a wide variety of advanced electronic materials, including materials for GaSb-based 2-um diode lasers, thermophotovoltaic power cells, and thermoelectric devices. In 1996, this group was combined with the Electro-optical Devices Group to form the Electro-optical Materials and Devices Group. In 1997, Dr. Spears became Leader of this combined group. In 1999, he was made a Fellow of the Military Sensors Symposium (MSS) {formerly the Infrared Information Symposium (IRIS)}. That year, he became a part-time Assistant Leader and then retired in 2000, but continued working as a part-time Senior Staff Member. Initially carrying out experimental research on a CO2 laser-based RF frequency reference, Dr. Spears continued working at Lincoln Laboratory until 2013. 

He has numerous patents, including the invention of X-ray lithography, X-ray lithography masks, resonant-optical-cavity infrared detectors, quantum-dot thermoelectric materials in PbSnTeSe, thermophotovoltaic materials and detectors in InGaAsSb, and imaging arrays for hazardous gas detection. 

Dr. Spears' interests have included mountain climbing (climbed Mt. Washington 4 times in January), camping, backpacking, hiking, cross-country skiing, boating, sailing, fishing, downhill skiing, photography and genealogy. He was also involved in scouting, having served as Cub Master, Den Leader, and Commissioner for Cub Scouting for the Nashua Valley Council. 

He was a member of the First Baptist Church, Marengo, Illinois and the First Congregational Church, Acton, Massachusetts, serving on various church committees. 

In 1962, he married Shirley Christine Olsson. They had two sons, David Mark Spears (1963) and Warren Olsson Spears (1966). The marriage ended in 1980 and he married Marcia Anne Hayde in 1989. Also in 1989, his son, David Mark Spears, married Wendy Hellene Bishop. They had two sons, David Nicholas Spears (1992) and Michael James Spears (1994). His wife Marcia has two children, Karen Elizabeth Hayde (1963) who married Stephen D'Allesandro and Michael Charles Hayde (1967) who married Niki Black. Michael and Niki have two children Joseph Charles Hayde (2007) and Audrey Hayde (2009). He is survived by all of the above. He was predeceased by his father, Richie Russell Spears, his mother, Marcella Wright Spears and wife Marcia A. Spears.