Mellon optical memory

Mellon optical memory was an early form of computer memory invented at the Mellon Institute (today part of Carnegie Mellon University) in 1951.[1][2] The device used a combination of photoemissive and phosphorescent materials to produce a "light loop" between two surfaces. The presence or lack of light, detected by a photocell, represented a one or zero. Although promising, the system was rendered obsolete with the introduction of magnetic-core memory in the early 1950s. It appears that the system was never used in production.

Computer memory and data storage types
General
Volatile
RAM
Historical
Non-volatile
ROM
NVRAM
Early-stage NVRAM
Analog recording
Optical
In development
Historical
  1. ^ Mellon Institute of Industrial Research: Computer Component Fellowship #347, Quart. Rep. no. 3 (Apr.–July 1951) Sec. I–VI; Quart. Rep. no. 5 (Oct.–Jan. 1952) Sec. I–V; Quart. Rep. no. 6 (Jan.–Apr. 1952) Sec. II, III, VI; Quart. Rep. no. 9 (Oct.–Jan. 1953) Section III.
  2. ^ Eckert, J. P. Jr. (1998-10-01). "A Survey of Digital Computer Memory Systems". IEEE Ann. Hist. Comput. 20 (4): 15–28. doi:10.1109/85.728227. ISSN 1058-6180. S2CID 17823128.