A Discrete Realization of Higher Resolution Phase Detection

Abstract:

To improve the resolution of optical meter in manufacturing machines, novel discrete higher resolution phase detection for optical grids in optical meter is proposed. It is well known that the output of optical grid is a pair of sinusoidal and co-sinusoidal signals. The way enriching the phase information roots upon three primitive elements: (1) the phase angle 2 per cycle can be encoded into eight /4 phase regions, (2) the chopping signal of each /4 region is either the replica or the mirror of the first phase region, and (3) amplitude-to-phase mapping is used to digitize the pair of sinusoidal and co-sinusoidal signals into a pulse sequence. The empirical result shows that the proposed diagram with an 8 bits A/D converter can digitize the resolution of a complete sinusoidal signal up to 800 pulses per cycle. When coupling to the manufacturing machines, the proposed phase splitter can promote their resolution to 1600 times.

• Periodical: Applied Mechanics and Materials (Volume 214)
• Pages: 882-886
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.214.882
• Online since: November 2012
• Authors: Ping Sung Liao, Chien Hua Lee
• Keywords: A/D Converter, Phase Division, Phase Range Mapping, Phase Splitter

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