MOEM scan engine for bar code reading and factory automation

Rockwell is in the state of technology transfer to manufacturing of a micro-opto-electro-mechanical scan engine with superior scanning performance for bar code reading and factory automation. The scan engine consists of three main components: actuator, mirrors, and control electronics. The first two components are fabricated on a silicon cantilever beam while the control electronics are presently hybrid. The actuator comprises of a bimorph layer covered with two metal layers. The mirror has a large area (several mm2) and it is micromachined with a surface flatness better than (lambda) /2. Actuator scan-angles greater than 22 degree(s) with high repeatability in performance are achieved. The scan engine was integrated with an existing Rockwell commercial bar code reader/decoder and successfully proven to read a two-character code 39 bar code. The system was capable of decoding the 13-mil label at 360 scans per second with a 100% successful read performance. Environmental testing of the device indicates that the scanner can operate at elevated temperatures up to 70 degree(s)C with minor fluctuations in frequency and scan angle. The scanner has also gone through a lifetime cycle test and it has survived more than 8 billion cycles during a period of 18 months. To increase the yield and the performance level of the device, theoretical study as well as dynamic simulation by finite elements modeling have been investigated and will be reported separately.