Hybrid surface measuring system for motion-blur compensation and focus adjustment using a deformable mirror

The recent growth in automation and microfabrication has led to a need for faster, more accurate inspections. This in turn requires fast and accurate image capture methods. A system has previously been proposed to obtain images without motion blur by controlling the line of sight to follow a moving object with a mirror, thereby decreasing inspection time. However, as this system follows only the line of sight, it corresponds only to the plane parallel to the direction of movement. Here, we propose a system for measuring non-planar surfaces by simultaneously controlling the line of sight and focus using a deformable mirror. In addition, the proposed system requires only one deformable mirror, whereas those from previous studies require multiple devices to control the line of sight and focus. Therefore, our proposed system can be downsized and applied to various measurement systems. We tested our system by measuring surface images of objects with curved and uneven surfaces under movement at 20 mm/s, at a distance of about 140 mm in front of the mirror. The system successfully obtained motion-blur-free, all-in-focus images. Moreover, we validated the effectiveness of the proposed system by comparing the captured images to those obtained using existing methods.