Optically activated data storage medium visually and electromagnetically reproduces a recorded signal. In an electric field, particles in heat-fluidized thermoplastic layer form a visible image of the recorded signal. Refluidizing the thermoplastic layer erases the signals. Very high data packing densities are achieved

Marks, A. M.

Shulman, A. R.

English

NASA Technical Reports Server

November 1970	 Brief 70-10247 
NASA TECH BRIEF 
NASA Tech Briefs announce new technology derived from the U .S. space program. They are issued to encourage commercial 
application. Tech Briefs are available on a subscription basis from the Clearinghouse for Federal Scientific and Technical 
Information, Springfield, Virginia 22151. Requests for individual copies or questions relating to the Tech B rief program may 
be directed to the Technology Utilization Division, NASA, Code UT, Washington, D.C. 20546. 
- 
____i- -	 ------	 ----
Optically Activated Magnetic Recording Tape 
An optically activated data storage medium has 
been developed on which the recorded signal can be 
seen as well as electromagnetically reproduced. 
On the recording tape is a thermoplastic layer in 
which rod-shaped, electrically conductive, half-wave 
dipole particles are embedded. The particles remain 
fixed until the thermoplastic layer is fluidized by-heat. 
When this is done in the presence of an electric field, 
the dipoles are aligned with the field, and the particle 
concentration forms a visible image of the recorded 
signal. A focused laser beam supplies the heat to 
locally fluidize the thermoplastic layer. 
Recorded signals may be erased by again fluidizing 
the thermoplastic layer and randomizing the orienta-
tion of the dipoles by applying a rapidly fluctuating 
electric field. 
Because of the extremely small area heated by the 
focused laser beam, very high data packing densities 
may be achieved by this system.
Note: 
Requests for further information may be directed to: 
Technology Utilization Officer 
Goddard Space Flight Center 
Code 207.1 
Greenbelt, Maryland 20771 
Reference: B70-10247 
Patent status: 
Inquiries about obtaining rights for the commercial 
use of this invention may be made to NASA, Code 
GP, Washington, D.C. 20546. 
Source: Arnold Shulman

Goddard Space Flight Center

and A. M. Marks of

Marks Polarized Corp.

under contract to

Goddard Space Flight Center

(GSC-10275, 10276) 
Category 01 
This document was prepared under the sponsorship of the National 
Aeronautics and Space Administration. Neither the United States 
Government nor any person acting on behalf of the United States
Government assumes any liability resulting from the use of the 
information contained in this document, or warrants that such use 
will be free from privately owned-rights.
https://ntrs.nasa.gov/search.jsp?R=19700000237 2020-03-17T00:15:46+00:00Z


Optically activated magnetic recording tape

Abstract

Similar works

Full text

Available Versions

NASA Technical Reports Server