Patent of the Month March

  Valerie Thomas ©

Illusion Transmitter

On occasion of International Women's Day on 8th of March, we highlight the work of the American physicist Valerie L. Thomas. The long-term NASA employee and pioneer of remote sensing created a three-dimensional optical illusion by means of concave mirrors and transmitted the image data via video. With the technology of the so-called "illusion transmitter" she contributed to the development of surgical instruments, televisions and video screens. As a thoroughbred scientist, Valerie Thomas was not pursuing commercial interests. Therefore, only a patent application (US4229761A) was filed in 1978 for the research result - our Patent of the Month March!

Thomas, who celebrated her 80th birthday in February, was born in 1943 in Maryland. From an early age she was interested in technology. At that time, in the 1950’s, scientific or technical interests were considered as to be unimportant for women. She was not encouraged to follow her technological aptitude neither in her home environment nor in the all-girls high school she attended. Moreover, as an African American, she was disadvantaged by fewer educational opportunities in a racially segregated society. However, against all odds, Thomas enrolled at Morgan State University as one of only two women majoring in physics. She was an excellent student and graduated with top marks in 1964. The motto of her alma mater "Growing the Future and Leading the World" proved to be characteristic for her further professional life. From the beginning of her career up to retirement, Valerie Thomas worked for NASA (National Aeronautics and Space Administration) in the field of satellite information.

As a data analyst, she first started in the development of computer data systems for satellite operations control centres. In 1970, Thomas took over the research and development management of image processing systems for "Landsat ", the first satellites to transmit multi-spectral images for the study of Earth resources from space. The scientist became an international expert on image and remote sensing data and was involved in pioneering research projects on their application.

As so often, the "illusion transmitter" was invented by coincidence. In 1976, at a scientific exhibition, she saw the illusion of a glowing light bulb, despite of being removed from the lamp socket. The optical illusion had been created by the reflection of a second light bulb in a socket beneath the top socket. The special three-dimensional effect is due to the use of concave mirrors, characterised by an inwardly curved shape of the reflecting surface. Unlike flat mirrors, creating images that appear to be inside or behind the mirror, concave mirrors reflect images with three-dimensional properties – you can observe the illusion effect in laughing booths at funfairs.

Fascinated by this observation, Valerie Thomas began in 1976 experiments for observing the relationship between an object and its mirrored image in relation to the positions of concave mirrors. She extended the research to transmitting video data of the concave mirror images over long distances in real time, believing that this could yield to improvements in video and even television. As a result, Thomas invented an image detector that, in combination with a second parabolic mirror, provides an image of the object in real time at the receiving end.

For her achievements on several high-renowned NASA projects, the exceptional scientist has received a number of awards, including the Goddard Space Flight Center Award of Merit and NASA's Equal Opportunity Medal. Thomas was also committed to the rights of minorities. Towards the end of her working life, she wrote her PhD-thesis on "Career Opportunities for Women and African Americans". Today, she still offers young scientists the support she never had and is mentoring young people engaged in Science Mathematics Aerospace Research and Technology, Inc. and the National Technical Association.

The Patent and Standards Centre wishes ongoing female power in R&D!

More information on the topic "Women and IP: Driving Innovation and Creativity" you will receive on World Intellectual Property Day on 26 April. Save the date!


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Sources Valerie Thomas

Lemelson-MIT program: Valerie Thomas

Entry in the Encyclopedia Britannica:  Valerie-Thomas

Patent document: US4229761A