Henry's entire professional career was spent in the research area of Bell Laboratories in Murray Hill, New Jersey.

Throughout his career, Henry worked at the forefront of semiconductor-based optical technologies and science: light-emitting diodes, semiconductor lasers, and photonic integrated circuits.

He was an inventor as well as an experimenter, with a particular interest in understanding the theory underlying semiconductor optical devices.

[3] Henry further realized that these discrete electron states would greatly alter the optical absorption edge of the semiconductor.

On March 7, 1975, Henry and Dingle filed a patent entitled "Quantum Effects in Heterostructure Lasers," which was issued on Sept. 21, 1976.

Early in his career, Henry identified the source of red light emission in gallium phosphide LEDs.

[9] Subsequently, red as well as green GaP LEDs were manufactured and used as indicator lights in a variety of applications.

Beginning in the mid-1980s, Henry (with R. F. Kazarinov) initiated a new photonic integrated circuit technology based on silica waveguides fabricated on silicon wafers.

The basic equations governing noise phenomena were derived from first principles and applied to specific examples.