The automatic alignment of a pinhole is realized in two dimensions and its function as a spatial filter is confirmed. A pinhole device surrounded by four photodiode cells fabricated by Si micromachining techniques is placed on a movable xy stage which consists of four shape-memory-alloy actuators. The feedback control based on the signal obtained from the integrated photodiode is confirmed to be feasible for aligning a pinhole in two dimensions even if the shape-memory-alloy actuators are disadvantageous for controlling its displacement including cross-interaction. The spatial filtering function of an automatically aligned pinhole is confirmed.
- Automatic alignment
- Si micromachining