Reactions: Liquid crystal technology

Letters to the editor

Liquid crystal technology

I enjoyed reading the article, “A Century of Chemistry and of C&EN” in the Aug. 7/14, 2023, issue of C&EN (page 18). I wanted to mention one development that was not covered in the piece. In 1966, my colleagues George Heilmeier, Lucian Barton, Joel Goldmacher, and Louis Zanoni and I developed and built the first display devices to use liquid crystal materials. The research was done at the David Sarnoff Research Center of the Radio Corporation of America (RCA) in Princeton, New Jersey. The goal was to develop a flat-screen television, and liquid crystal technology was believed to be one possible way to achieve that goal.

We discovered that mixtures of anil nematic liquid crystal compounds resulted in materials that had a wide nematic range, making possible practical electronic display devices. To my knowledge, it was the first time that synthetic organic compounds were used as the active elements in electronic devices. This technique of mixing nematic compounds to obtain a wide operating temperature range eventually became the industry standard and is used to this very day to tailor materials to meet specific applications.

Unfortunately, we were not permitted to publish the results until 1968, when the RCA held a news conference to announce the development. We demonstrated digital clocks, multimeters, and other color displays that used mixtures of liquid crystal compounds operating over a wide temperature range. The development was covered in the Aug. 19, 1968, issue of C&EN.

The impact of this announcement was truly remarkable. Researchers around the world realized that liquid crystals might indeed be important for advanced electronic display devices. Professor George Gray and his students at the University of Hull in England later developed materials using mixtures of biphenyl liquid crystal compounds, which became the industry standard. Today, liquid crystal displays are used in many products, including flat-screen televisions, cell phones, computer displays, medical devices, and more, composing an industry now worth hundreds of billions of dollars.

Joseph A. Castellano
San Jose, California