O3.4 - Optical Incremental Rotary Encoder in Low Cost Design

Event
SENSOR+TEST Conferences 2009
2009-05-26 - 2009-05-28
Congress Center Nürnberg
Band
Proceedings OPTO 2009 & IRS² 2009
Chapter
OPTO 3 - Applications and Devices
Author(s)
D. Hopp, C. Pruss, W. Osten - Universität Stuttgart, Stuttgart, Germany, J. Seybold, V. Mayer, H. Kueck - Hahn-Schickard Gesellschaft (HSG-IMAT), Stuttgart, Germany
Pages
87 - 92
DOI
10.5162/opto09/o3.4
ISBN
978-3-9810993-6-2
Price
free

Abstract

Rotary encoders are used for angular measurements in numerous applications like rotating machin parts, electrical motors or for example to detect the steering angle in cars. There are differed encoding principles available such as potentiometric, capacitive, inductive or optical, with the optic systems reaching the highest angular accuracy. As a disadvantage the resolution enhancement of optic encoder systems is associated with increasing cost. Considering the need for competitive sensors, we have developed a new concept for low cost opbc; rotary encoders. The basic idea is to use a micro patterned plastic disc with a met coating, as it is used for a Compact Disc or DVD. This encoder disc can be manufactured by conventional DVD injection compression moulding process. With this well known technique it is possibl to create highly precise micro patterns while running a cost effective process for high numbers of parts. The mechanical and electronic design and the realization of this new kind of optical rotary encoders performed by our project partner, HSG-IMAT. ITO focuses on the optical design as well as the fabricatia of the testmaster discs. The testmasters are directly written into photo resist on the circular laser writin system CLWS 300M.

Download