Design of incremental grating ruler online measuring- displacement system based on LabVIEW

To accommodate the requirements of precise displacement feedback devices in micro-electronic technology, an on-line measurement system of the grating ruler is designed. This system uses a kind of virtual instrument called LabVIEW and digital image processing technology to detect the displacement, that consists of the PXI case of National Instruments, the frame grabber and the precision motion platform. The experimental tests demonstrate that in the distance range of 150 mm, the motor speed is within 1.25 mm/s, the maximum displacement error within 0.04 mm. This system is simple, can be operated-controlled in real time and observed-debugged online. It's not only adapts to the measuring-displacement, but also suits the surface detection, encapsulation and other fields in the microelectronics manufacturing.