Browse Prior Art Database

Optical Potentiometer

IP.com Disclosure Number: IPCOM000081937D
Original Publication Date: 1974-Sep-01
Included in the Prior Art Database: 2005-Feb-28
Document File: 2 page(s) / 35K

Publishing Venue

IBM

Related People

Dunik, SL: AUTHOR

Abstract

Available potentiometers utilize a wiper which slides over the surface of a disk of uniformly resistive material. Such mechanical contact causes wear and circuit noise. The optical potentiometer of Fig. A not only avoids these drawbacks, but also provides complex resistance changes as a function of manual shaft rotation.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 2

Optical Potentiometer

Available potentiometers utilize a wiper which slides over the surface of a disk of uniformly resistive material. Such mechanical contact causes wear and circuit noise. The optical potentiometer of Fig. A not only avoids these drawbacks, but also provides complex resistance changes as a function of manual shaft rotation.

In Fig. A, photoresistor P receives light from light source L as reflected by reflective surface R of disk D. Shaft S is journaled for rotation and is attached to disk D. Between angular positions A and B, surface R is provided with a reflective coating whose reflectivity varies with angular rotation in accordance with any desired Fig. B relationship.

By manually rotating shaft S, the resistance between terminals T of photoresistor P varies in the same way as the reflectivity depicted in Fig. B.

1

Page 2 of 2

2

[This page contains 3 pictures or other non-text objects]