April 3, 1959


A Study in Dimensional Scaling as applied to Electronic-Device Microminiaturization


Douglas C. Engelbart

Stanford Research Institute

Menlo Park, California


Similtude is an old and established art in the engineering profession. It has been used very extensively for ship and airplane design where great dependence is placed upon data obtained from small models in towing tanks and wind tunnels. Structural models (bridges, dams, buildings, etc.), other fluid-flow models (weirs, spillways, etc.) and chemical engineering models (pilot plants, etc.) have also been used to obtain experimental information with small-sized models about prototypes which are too large and/or expensive to experiment with.

In a study directed toward microminiaturizing electronic devices, it is revealed that judgement and intuition obtained from experience with "normal-sized" devices are not directly applicable to the scaled-down models. It now becomes useful to apply similtude to a situation which is reversed from previous engineering applications - we want to know how to predict behaviour of the small model from that observed with the large model. Determination and study of the dimensional transformations which must be applied to a device when its length dimensions are changed, in order that the relative functional characteristics remain unchanged, has been most interesting, and has helped greatly to permit the utilization of "normal-size" experience. The approach would appear useful for studying the microminiaturizing of any type of component, and some useful generalizations are readily available. Our immediate specific application is to magnetic components, and some very important conclusions have been obtained.




Studying similtude ... note the definition for analogies there, and realize that the physical realization of logic is essentially the same thing ... i.e., looking for a physical analogue to the logic equations, with preference for small size, low power, high speed, reliability, and low cost ... etc...