Leine & Linde AB
Develop manufacture and sell incremental & absolute encoders. Robust products for industrial applications.
http://www.leinelinde.se/

Photocraft, Inc.
Manufacturer of hollow shaft encoders, wheel encoders, programmable encoders, and absolute encoders. Data sheets viewable online and in PDF.
http://www.photocraftencoders.com

NorthStar Technologies Inc
Dynapar is a manufacturer of rotary encoders, absolute encoders, optical encoders and resolvers. Dynapar Encoders, Northstar, and Harrowe brands for every application and fast delivery.
http://www.northstarencoders.com/

Gurley Optical Encoders
Manufacture of rotary and linear optical encoders, absolute and incremental encoders and quadrature encoders. All data sheets in PDF.
http://gpi-encoders.com

Greenbank Machinery and Plant Ltd
Distributors of optical encoders, rotary encoders, shaft encoders and tachogenerators. From UK.
http://tachogenerators.co.uk/

Stegmann Inc.
Technical specifications and CAD drawings available online for our Linear Encoders, Absolute Encoders and Incremental Encoders.
http://www.stegmann.com/

Hohner Corp.
Optical Encoders for Hazardous Areas and Systems for Tomorrows Digital OilField
http://www.hohner.com/

Codechamp
Gamme de codeurs optiques rotatifs, codeurs rotatifs, codeurs incrémentaux...Les avantages de la solution codeurs optiques Codechamp !!
http://www.codechamp.com

Industrial Encoders Direct
UK Encoder manufacturers and emergency repairs specialists, Distributors of all encoders, linear, incremental, absolute shaft & rotary encoders, solid, semi-hollow, parallel & shaft encoders, suppliers throughout the United Kingdom & Worldwide
http://www.industrialencodersdirect.co.uk

Division in Mean and Extreme Ratio
The base angle of the largest trinalges of most representations of Sri Yantra are about 52 degrees, close to the base angle of the Great Pyrmaid of Cheops, which is 51deg50'. With such a base angle, the ratio of the hypotenuse to half the base is phi, the Golden Ratio.
http://alumni.cse.ucsc.edu/~mikel/sriyantra/golden.html