Controllers Provide Sub-Nanometer Resolution
Providing sub-nanometer position resolution without compromising speed or throughput, ACS Motion Control's advanced SPiiPlus and MC4U multi-axis motion controllers feature a powerful Sin-Cos encoder multiplier that enables accurate, high-resolution positioning while reducing jitter and settling times. The SPiiPlus Sin-Cos encoder multiplier features 1Vptp differential inputs that use a maximum theoretical Sin-Cos encoder multiplication factor of 65,536 to achieve the required high resolution of today's demanding motion applications. With input frequencies rated up to 2.5MHz, the achievable maximum velocity is not dependant on the selected multiplication factor enabling the use of ultra high-resolution laser feedback devices. "When high-speed and nanometer axis position resolutions are required, OEMs have been limited to expensive laser interferometer feedback systems. With our internal SPiiPlus Sin-Cos encoder multiplier, users now have a much less expensive alternative by using an analog Sin-Cos encoder solution," said Evan Reed, ACS Vice President. The SPiiPlus PCI and linear drives were tested on a high performance XY table used for wafer inspection with Sin-Cos encoder resolutions of 4nm (250 lines per mm). Using a multiplication factor of 8,192, ACS engineers measured a jitter of ±2 encoder counts, which is equivalent to ~1nm. At this high resolution, the axis achieved velocities up to one meter per second.