Richard Gordon Gould (July 17, 1920 – September 16, 2005) was an American physicist who is sometimes credited with the invention of the laser and the optical amplifier. (Credit for the invention of the laser is disputed, since Charles Townes and Arthur Schawlow were the first to publish the theory and Theodore Maiman was the first to build a working laser). Gould is best known for his thirty-year fight with the United States Patent and Trademark Office to obtain patents for the laser and related technologies. He also fought with laser manufacturers in court battles to enforce the patents he subsequently did obtain.

Gould was born in New York City in 1920, the son of Helen Vaughn (nee Rue) and Kenneth Gould. He was the oldest of three sons. His father was the founding editor of Scholastic Magazine Publications in New York City. His mother encouraged his interest in inventors such as Thomas Edison and gave him a toy Erector set at an early age. He grew up in Scarsdale, a small suburb of New York, and attended Scarsdale High School. He earned a Bachelor of Science in physics at Union College, where he became a member of the Sigma Chi fraternity, and a master's degree at Yale University, specializing in optics and spectroscopy. Between March 1944 and January 1945 he worked on the Manhattan Project but was dismissed due to his activities as a member of the Communist Political Association. In 1949 Gould went to Columbia University to work on a doctorate in optical and microwave spectroscopy. His doctoral supervisor was Nobel laureate Polykarp Kusch, who guided Gould to develop expertise in the then-new optical pumping technique. In 1956, Gould proposed using optical pumping to excite a maser, and discussed this idea with the maser's inventor Charles Townes, who was also a professor at Columbia. Townes gave Gould advice on how to obtain a patent on his innovation, and agreed to act as a witness.

By 1957, many scientists including Townes sought a way to achieve maser-like amplification of visible light. In November of that year, Gould realized that one could make an appropriate optical resonator by using two mirrors as a Fabry–Pérot interferometer. Unlike previously considered designs, this approach would produce a narrow, coherent, intense beam. Since the sides of the cavity did not need to be reflective, the gain medium could easily be optically pumped to achieve the necessary population inversion. Gould also considered pumping of the medium by atomic-level collisions, and anticipated many of the potential uses of such a device.

Gould recorded his analysis and suggested applications in a laboratory notebook under the heading "Some rough calculations on the feasibility of a LASER: Light Amplification by Stimulated Emission of Radiation"—the first recorded use of this acronym. Gould's notebook was the first written prescription for making a viable laser and, realizing what he had in hand, he took it to a neighborhood store to have his work notarized. Arthur Schawlow and Charles Townes independently discovered the importance of the Fabry–Pérot cavity—about three months later—and called the resulting proposed device an "optical maser". Gould's name for the device was first introduced to the public in a conference presentation in 1959, and was adopted despite resistance from Schawlow and his colleagues.

Eager to achieve a patent on his invention, and believing incorrectly that he needed to build a working laser to do this, Gould left Columbia without completing his doctoral degree and joined a private research company, TRG (Technical Research Group), in Long Island, New York. He convinced his new employer to support his research, and they obtained funding for the project from the Advanced Research Projects Agency, with support from Charles Townes. Unfortunately for Gould, the government declared the project classified, which meant that a security clearance was required to work on it. Because of his former participation in communist activities, Gould was unable to obtain a clearance. He continued to work at TRG, but was unable to contribute directly to the project to realize his ideas. Due to technical difficulties and perhaps Gould's inability to participate, TRG was beaten in the race to build the first working laser by Theodore Maiman at Hughes Research Laboratories.

During this time, Gould and TRG began applying for patents on the technologies Gould had developed. The first pair of applications, filed together in April 1959, covered lasers based on Fabry–Pérot optical resonators, as well as optical pumping, pumping by collisions in a gas discharge (as in helium–neon lasers), optical amplifiers, Q-switching, optical heterodyne detection, the use of Brewster's angle windows for polarization control, and applications including manufacturing, triggering chemical reactions, measuring distance, communications, and lidar. Schawlow and Townes had already applied for a patent on the laser, in July 1958. Their patent was granted on March 22, 1960. Gould and TRG launched a legal challenge based on his 1957 notebook as evidence that Gould had invented the laser prior to Schawlow and Townes's patent application. (At the time, the United States used a first to invent system for patents.) While this challenge was being fought in the Patent Office and the courts, further applications were filed on specific laser technologies by Bell Labs, Hughes Research Laboratories, Westinghouse, and others. Gould ultimately lost the battle for the U.S. patent on the laser itself, primarily on the grounds that his notebook did not explicitly say that the sidewalls of the laser medium were to be transparent, even though he planned to optically pump the gain medium through them, and considered loss of light through the sidewalls by diffraction. Questions were also raised about whether Gould's notebook provided sufficient information to allow a laser to be constructed, given that Gould's team at TRG was unable to do so. Gould was able to obtain patents on the laser in several other countries; however, he continued fighting for U.S. patents on specific laser technologies for many years afterward.

In 1967, Gould left TRG and became a professor at the Polytechnic Institute of Brooklyn, now New York University Tandon School of Engineering. While there, he proposed many new laser applications, and arranged government funding for laser research at the institute.

Gould's first laser patent was awarded in 1968, covering an obscure application—generating X-rays using a laser. The technology was of little value, but the patent contained all the disclosures of his original 1959 application, which had previously been secret. This allowed the patent office greater leeway to reject patent applications that conflicted with Gould's pending patents. Meanwhile, the patent hearings, court cases, and appeals on the most significant patent applications continued, with many other inventors attempting to claim precedence for various laser technologies. The question of just how to assign credit for inventing the laser remains unresolved by historians.