Meet Dr. Thomas Mensah: A Fiber Optics Technologies Innovator
The use of light pulses to transmit data through cables from one place to another is known as fiber optic communication. Compared to many other forms of data transmission, fiber optics has exceptionally low data loss, a lack of power issues when traveling long distances and carries a much higher amount of data. Telecommunications and the Internet have been greatly influenced by fiber optics technologies which have allowed those industries to mature with more robust products and services.
With the arrival of February comes the return of our celebration of Black History Month, where we profile innovations by African-American inventors that have shaped our world for the better. Last year, we published profiles of Granville T. Woods, known as “the Black Edison,” who invented induction telegraphy for preventing railroad collisions. We also profiled George Washington Carver, known as “God’s Scientist.” We also researched the patent activities of historically black colleges and universities (HBCUs) and published a survey of impressive patents issued to those institutions.
This year, we’re profiling the life and career of another prominent black inventor, Dr. Thomas Mensah, a pioneer in fiber optics manufacturing and communications systems. Although the history of fiber optics includes a long list of engineers and inventors making contributions over decades, Dr. Mensah’s particular improvements to the process of making fiber optic cables dramatically improved the cost-efficiency of producing those cables, clearing the way for a much greater degree of fiber optics technologies at work in our world. In his other work, Dr. Mensah increased the practical applications of fiber optics and has also sought to improve the status of African-American inventors and historical figures, making him a particularly interesting profile subject for Black History Month.
Thomas Mensah’s Early Life and Education
From an early age, Mensah displayed a propensity for intellectual behavior. Born in 1950 in Kumasi, Ghana, a young Mensah could read newspapers and converse fluently in French with business associates of his father’s, a shipper of cocoa products to French chocolate makers. His fluency in French helped him to win different levels of the National French Contest (Le Grand Concours) in 1968 and in 1970.
Mensah’s education was commensurate with his mental capabilities. He studied at a prestigious boys school known as Adisadel College in Cape Coast where he excelled in science and math. Mensah would continue on to study chemical engineering at the University of Science and Technology Kumasi in Ghana, which he attended as an honors student and from which he graduated in 1974.
Before beginning his career as an American engineer, Mensah engaged in a fellowship awarded by the French government to study chemical engineering at the University of Science and Technology at Montpellier, France. He would graduate from that school in 1978 with a Ph.D after also having completed a program at the Massachusetts Institute of Technology the year before.
Dr. Mensah’s Early Career and Fiber Optics at Corning
Dr. Mensah came to the United States in 1980 after taking a job as a research engineer with Air Products & Chemicals of Allentown, PA. Here, Dr. Mensah showed a remarkable ability in understanding chemical qualities for improving manufacturing processes.
One of Dr. Mensah’s early assignments at the company was to observe the mixing process involving the injection of a catalyst into polyvinyl acetate, or PVAC. Poor quality mixtures created by the mixing process resulted in a PVAC product that cured improperly and was the cause of a great deal of factory delays. Dr. Mensah discovered that by changing the configuration of the mixing blades and altering their notch depth, the catalyzing reactant could be mixed more thoroughly for a purer PVAC blend. This greatly diminished factory delays at Air Products & Chemicals and improved the efficiency of the entire process.
By 1983, Dr. Mensah had joined the engineering team of Corning Glass Works in Corning, NY. His assignment with this company was to address efficiency problems sustained during fiber optic cable manufacturing processes. The fragility of the glass fiber optic wires which the company manufactured caused them to snap easily if the drawing and coating phases of manufacturing fiber optics were configured to produce more than two meters per second of wire.
Focusing on the coating phase of producing fiber optic wire, Dr. Mensah noted that there were tiny bubbles being trapped on the coating surface as it cured. These bubbles served to weaken the strength of these wires, making them more brittle, and also caused losses in data transmission, reducing the speed at which data could travel through the wire. Dr. Mensah called for carbon dioxide gas to be injected near the boundary layer formed during the coating process, which prevented the bubbles from forming. The resulting fiber optic wire had a greater durability and could be produced at rates of up to 20 times the previous production speed without breaking.
Dr. Mensah holds more than a dozen patents and was issued seven patents in fiber optics technologies over the course of six years. We were able to find a couple of patents assigned to this inventor during his time at Corning Glass Works. In December 1988, Dr. Mensah was part of a team of Corning inventors who were issued U.S. Patent No. 4792347, which is titled Method for Coating Optical Waveguide Fiber. This patent protects the method of using carbon dioxide as a purge gas to reduce air entrainment and bubble inclusions in the liquid coating of a glass optical fiber. Dr. Mensah is also one of two inventors listed on U.S. Patent No. 4636405, issued under the title Curing Apparatus for Coated Fiber.
The curing apparatus for a coated fiber claimed here includes an ultraviolet energy-generating lamp that focuses ultraviolet light to cure a coating which is drawn along an axis. The invention also incorporates a jacket through which an infrared energy-absorbing fluid flows, cooling the cured coating without vibrating the fiber excessively. U.S. Patent No. 4531959, entitled Method and Apparatus for Coating Optical Fibers, also lists Dr. Mensah as an inventor. It was issued in July 1985 to protect an apparatus that included a sizing die, a sleeve with fiber input and output ends, an inner flow chamber surrounding the sleeve and a means for supplying coating liquid to the inner chamber to provide a concentric coating for an optical waveguide fiber that has a low incidence of bubbles.
Fiber Optics and Military Technology at AT&T Bell Laboratories
As Dr. Thomas Mensah’s profile on The Black Inventor Online Museum’s website reports, the engineer’s groundbreaking discoveries at Corning Glass Works would merely be the first portion of his career. By 1986, he had joined Georgia’s AT&T Bell Laboratories, now known as Bell Labs, where he began work on the application of fiber optics to guidance technologies which could be utilized in guided missile systems and other military applications.
Dr. Mensah was able to utilize fiber optics to create a guidance system for missiles that incorporated a small camera which was installed within the missile’s nose. The images captured by that camera could be delivered to a pilot, giving them a technique for locking onto a target with an incredible accuracy. The fiber optics missile guidance systems were capable of working while traveling at the speed of sound and were utilized in Patriot missiles and other guided weaponry used by the United States in the Gulf War.
We were able to find another trio of patents that included Dr. Mensah as an inventor which showcase the innovations he helped to develop while at AT&T Bell Labs. The highly durable fiber optics capable required to work at high speeds for missile guidance systems is disclosed by U.S. Patent No. 5035169, issued under the title Guided Vehicle System in July 1991. The guided vehicle system claimed here includes a control station which controls a vehicle and a package of optical fiber that contains a bobbin around which is wound a plurality of convolutions of optical fiber and a curable adhesive material applied to the outwardly facing surface portions of the convolutions. U.S. Patent No. 5064490, entitled Methods of Providing an Optical Fiber Package, was issued in November 1991 to Dr. Mensah et. al., protecting the techniques for manufacturing the optical fiber package comprised of optical fiber wound about a bobbin. The patent claims the method of winding optical fibers around a bobbin and applying a silicone adhesive material to each layer of optical fiber. The optical fiber package developed for a weapons system is also the focus of U.S. Patent No. 4955688, which is titled Optical Fiber Package and Methods of Making. Issued in September 1990, it claims a package of elongated optical transmitting medium which is disposed in a plurality of adjacent convolutions and a silicone adhesive material applied to the convolutions.
Other Aspects of the Work of Dr. Mensah: From Aerospace Materials to the Success Park
Although Dr. Mensah was responsible for some legendary innovations at Corning Glass and AT&T, many other areas of technological development have been impacted by his inventive genius. Profiles of the inventor claim a range of invention that includes semiconductors designed for space communications, tank gun barrel replacements and solid state rechargeable cell phone batteries. Dr. Mensah’s aerospace innovations helped him build the high tech firm he founded in Norcross, GA, known as Supercond Technologies, which helped to develop advanced structural materials for American fighter aircraft. Mensah is also currently the president and director of Georgia Aerospace Systems Manufacturing, which is also focused on research and development in aerospace materials.
The technological achievements made by Dr. Mensah in his career have led to a great deal of official recognition for his work. Honors earned by the inventor include the Corning Glass Works Industrial Outstanding Contributor Award for Innovation in Fiber Optics, 1985; AT&T Bell Laboratories High Performance Award, 1988; and the American Institute of Chemical Engineers (AIChE)’s William Grimes Award for Excellence in Chemical Engineering, 2006. Most recently, it was announced that Dr. Mensah would be an incoming fellow to the National Academy of Inventors, where he will be inducted with other fellows at a special ceremony during March of this year at CalTech in Pasadena, CA.
Dr. Mensah has also worked in recent years to improve the profile of black inventors and try to bring more focus to science education. Speaking to a team of students at the November 2014 Be U Hackathon contest in Redmond, WA, sponsored by Microsoft, Dr. Mensah was quoted in this article published by The Hays Post as saying, “It doesn’t matter what you look like, where you’re from… It matters what you do.” Having authored a couple of books on fiber optics and semiconductor engineering, Dr. Mensah wrote The Right Stuff Comes in Black,