A 26-Bit Absolute Encoder System
David J. Barlow, Bobby L. Ulich, David W. Latham · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1986
In October, 1985, new encoder readout electronics were installed on the MMT to read the existing absolute encoders. With the new electronics, the angular resolution of the encoder system has been increased from 24 bits (0.077 arcseconds) to 26 bits (0.019 arcseconds) and the amplitudes of the raw uncorrected errors related to the period of the InductosynsTM* have been reduced from a few arcseconds to the order of +/- 0.5 arcseconds or better.