Updated 31-XII-2018

Dr. Gibert H. Reiling

This article was written by fellow lamp engineer and collector Edward J. Covington, and originally appeared on his own website of biographical sketches of persons involved in the lamp industry. Following his passing in February 2017, and with kind permission of his family, Ed's words have been preserved here in the hope of maintaining access to his writings for the benefit of subsequent generations.

Gilbert H. Reiling12

Gil Reiling is a native of St. Paul, Minnesota, having been born September 19 1928. He received a bachelor's degree from St. Thomas College in Minnesota, a Master's degree from the University of North Dakota and a Doctor of Philosophy degree in Physics from the University of Missouri in 1957. His future work activities were to be with the General Electric Company - first at their Research Laboratory in Schenectady, New York.

He is widely acknowledged as being the father of the modern metal halide discharge lamp, which will be described in detail in the section below. In an interview in 1996 the following was reported12:

"In 1959, Gilbert Reiling at General Electric's Schenectady Research Lab began working on the thermodynamics of the mercury discharge. By June 1960 he reported to lab management that he had made lamps with "twice the luminous output" of a standard 400 watt mercury-vapor lamp and "with a white color which appears more pleasing to the eye." His lamps contained various mixtures of sodium-iodide and thallium-iodide. GE began an intensive development program, and announced a commercial metal halide lamp in 1962."
In 1961 Reiling left the Research Laboratory. He spent his remaining working career with the General Electric Lighting Business Group at Nela Park in E. Cleveland, Ohio. At Nela Park he first became Manager of Advanced Product Engineering for the Photo Lamp Department. This position was followed by several appointments in the Large Lamp Department: Incandescent Engineering, Quality Control and Fluorescent Engineering. He became Manager of Large Lamp Engineering in 1971 and Manager of Engineering of the Incandescent Lamp Department in 1974. In 1980 Reiling became Manager of Advanced Lighting Applications and Industry Standards in the Lighting Technology Division. He retired about 1990.

Dr. Reiling has been a sought-after speaker and in the late 1980s he and his wife spent three weeks in China while he lectured, being part of the United States Illumination Engineering Delegation. He received the 1987 Manufacturer Medal and Purse, given under the terms of the James McGraw Award for Electrical People, and on February 9, 1992 he was inducted into the Hall of Fame for Science, Industry and Technology at the Ohio Center for Science and Industry in Columbus, Ohio.

Gilbert Reiling married Margaret A. Eckert on June 7, 1952. They have children Mary, Anne, Stephen, Vincent, Eileen, Louise, Gilbert and Margaret. Gilbert and Margaret Reiling reside in a rural area east of Cleveland8.

Development of the Metal Halide Lamp
The writer is going to stray away from his usual subject of the incandescent lamp to comment on a lamp inventor, as well as a discharge light source, which he invented, that is not only efficient but one which emits white light. This subject is broached here because it is felt that those persons who make life better for the rest of us should be made known - even if the details of those lives are sometimes difficult to ascertain.

In the year 1962 a marked advancement was made in developing a lamp that is not only efficient but also one that gives white light. This new lamp was an improved version of the mercury lamp, which yields light of a bluish nature. The inventor of that new lamp is Dr. Gilbert H. Reiling, now retired. A brief description of the metal halide lamp is repeated here verbatim from an article in a GE publication that appeared in 19623

"The most efficient source of white light in the history of electric lamps was announced this February by Dr. Guy Suits, General Electric vice president and director of research.

"The new metallic-vapor lamp, because of its high efficiency and improved color, 'has the potential to revolutionize the lighting of streets, highways, industrial and other large indoor areas, stadiums, sports arenas, and shopping centers,' said Suits.

"In side-by-side demonstrations, the new developmental lamp was shown to be nearly five times as efficient as conventional incandescent lighting, and of comparable whiteness. Contrasted to standard mercury light sources, the new lamp has up to twice the efficiency and avoids the bluish color that has characterized lamps of this type in the past.

" 'One secret of the new lamp is the use of small amounts of metallic elements other than mercury, including sodium and thallium,' Suits said. He indicated, however, that details of the lamp's construction and ingredients would not be made public at the present time.

"Inventor of the lamp is Dr. Gilbert H. Reiling, who became interested in light sources while performing basic scientific studies of gas discharges as a physicist at the Research Laboratory. Contributing to the development are the laboratory's long-time programs in studies of arc temperatures, excitation and energy transfer mechanisms, and spectral characteristics.

"A number of unique new structural materials also have been incorporated in the new lamp, and operation under new and carefully controlled conditions of pressure and temperature also are credited with helping achieve what Suits called 'the best combination of efficiency and color in nearly a century of research aimed at improving electric lighting.'

"He explained that the new ingredients in the lamp serve to produce intense 'spectral lines' in that part of the spectrum which can be seen by the human eye, particularly in the orange and red regions. Efficiency is thus increased, since more of the electric energy is converted into visible light. Greater 'whiteness' is achieved because the additional spectral lines give a wider variety of visible colors than are produced in ordinary lamps of this type.

"The light produced by the new type of lamp can appear white if desired. It may also be designed to emphasize certain parts of the spectrum for special applications. Luminous efficiencies ranging from 70 to 110 lumens per watt are obtained, in contrast to a maximum of about 52 lumens per watt with mercury alone, and 56 with the addition of a phosphor to the bulb wall. Ordinary 100-watt incandescent lamps produce approximately 17 lumens per watt, although larger incandescent bulbs have somewhat higher efficiencies.

"The new metallic-vapor lamps are now being studied in a variety of forms and life tests are in progress. Additional research, development and life-testing will be required before introduction of a product can be considered..."

The new metal halide lamp, known within General Electric as the MultivaporTMlamp, was introduced in New York at the World's Fair of 1965, and is illustrated below.

Mercury lamp on the left1 and a metal halide (MultivaporTM) lamp on the right (U.S. 3,234,421)

"Ingredients in the new lamp serve to produce intense spectral lines in that part of the spectrum that can be seen by the eye, particularly orange and red regions."3

Improved efficiency and color control of the new metallic-vapor lamp described on page 8 is demonstrated in photo above. All three booths are illuminated with light of the same intensity. Signs on rear walls show the power inputs, indicating differences in efficiency of the light sources. At left, 800 watts of ordinary mercury lighting produces light of a characteristic bluish color. Booth at right is illuminated by standard incandescent lamps totaling 1900 watts. The new lamp (center booth) consumes only 400 watts of power to produce equivalent intensity and comparable whitness. (Note: Because of the physiological and psychological aspects of color viewing, and the technical limitations of color photography and printing, a photograph such as this represents only an approximation of the actucal effect of seeing the results 'live.' It is believed, however, that this illustration gives a fair representation of the observable improvement in whiteness and efficiency offered by the new metallic-vapor lamp.)"3

I am grateful to Dr. Gilbert H. Reiling for sharing some of his biographical information with me. He has always been an upbeat kind of person who contributed to science and engineering in many ways. His venture into management did not result in the termination of his interest and contributions to lamp development; this can be realized by looking at the dates of his patents. Because he had the requisite education in thermodynamics, and the required amount of determination, his metal halide lamp invention resulted in a white light source of extremely high efficacy - the upper limit of which has yet to be reached.

Thanks are also given to Janice L. Fraser and Jo S. Farnham, both at General Electric's Nela Park facility. Ms Farnham looked through back issues of the GE News for me and also provided photocopies of articles.

  1. US 2,976,451 - Electric Discharge Device - 1961/03/21
  2. US 3,049,639 - High Power Switch Tube - 1962/08/14
  3. CA 663,118 - High Power Switch Tube - 1963/05/14
  4. US 3,234,421 - Metallic Halide Electric Discharge Lamp - 1966/02/08
  5. US 3,236,269 - Photoflash Lamp Filling Machine - 1966/02/22
  6. US 4,316,116 - Triple-Coil Incandescent Filament - 1982/02/16
  7. US 4,361,782 - Jacketed Discharge Lamp Having Oxidizable Fail-Safe Switch - 1982/11/30
  8. US 4,420,801 - Reflector Lamp - 1983/12/13
  9. CA 1,172,682 - Reflector Lamp - 1984/08/14
  10. CA 1,198,147 - Triple Coil Incandescent Filament - 1985/12/17
  11. US 4,675,794 - Adjustable Mount For A High Intensity Lamp - 1987/06/23
  12. US 4,678,960 - Metallic Halide Electric Discharge Lamps - 1987/07/07
  13. US 4,723,097 - Rapid Restrike Metal Halide Lamp... Method Of Operating Such - 1988/02/02
  14. CA 1,238,936 - Reflector Lamp And Lighting Systems ...For Architectural Lighting - 1988/07/05
  15. US 4,808,876 - Metal Halide Lamp - 1989/02/28
  16. US 4,853,597 - Rapid Restrike Metal Halide Lamp...Method Of Operating Such - 1989/08/01
  17. CA 1,301,237 - Asymmetric Arc Chamber For A Discharge Lamp - 1992/05/19

References & Bibliography
  1. GE Lamp Bulletin, Large Lamp Department, Cleveland, Ohio 44112, January 1956, pp.41-49.
  2. "Metallic Halide Electric Discharge Lamps", Gilbert H. Reiling, U. S. Patent No. 3,234,421, filed Jan 23 1961, granted Feb 8 1966.
  3. "New Light Source", Research Laboratory Bulletin, General Electric Company, Schenectady, New York, Spring 1962, p.8.
  4. "Characteristics of Mercury Vapor-Metallic Iodide Arc Lamps", Gilbert H. Reiling, J. Opt. Soc. Am., Vol.54, pp.532-540, 1964.
  5. "The General Electric Story, 1876-1986", Hall of History Foundation, Schenectady, New York, 1981, p.57.
  6. "Review of Metal Halide Lamps", Alexander Dobrusskin, 4th International Symposium on the Science and Technology of Light Sources, University of Karlsruhe, F. R. Germany, April 7-10 1986, pp3-19.
  7. "Lampmakers Glow in Statue Light", General Electric Lighting Business Group GE News, Jul 8 1986.
  8. "Gilbert H. Reiling", Who's Who in Technology, Vol5 (Who's Who in Physics & Optics), North American Edition, 1986, p.182.
  9. Dr. Gilbert H. Reiling, Citation, Manufacturers Medal - 1987, The James H. McGraw Award. (This is at least the second person from Nela Park to receive this award; in 1935 Dr. Matthew Luckiesh was also a recipient.)
  10. "A Bright Idea - Munson Resident's Discovery Earns Place in Hall of Fame", A. Zachary Stein, Geauga Times Leader, Feb 3 1992, p.A5.
  11. "A Shining Light Gets Honored - Inventive Ohioan to Hold Spotlight at Hall of Fame", Karen Sandstrom, The Plain Dealer, Feb 8 1992.
  12. http://americanhistory.si.edu/lighting/bios/reiling.htm
  13. http://www.endex.com/gf/buildings/liberty/libertyfacts/LibertyTorch.htm
  14. http://ep.espacenet.com/search97cgi/s97_cgi.exe?Action=FormGen&Template;=ep/en/advanced.hts
  15. General Electric Lighting Business Group GE News, Feb 28 1986, Mar 14 1986, Mar 27 1986, Jul 8 1986, Nov 14 1986.