Structure light telecentric stereoscopic vision 3D measurement system based on Scheimpflug condition

• Designs a new three dimensional measuring system for micro components.
• Combining Scheimpflug condition with structure light and telecentric stereoscopic vision.
• Enlarge the depth of focus without decreasing the lens's resolution.
• Wide measurement range, high accuracy, fast speed and low price.
• Calibration of telecentric camera on Scheimpflug condition.

We designed a new three-dimensional (3D) measurement system for micro components: a structure light telecentric stereoscopic vision 3D measurement system based on the Scheimpflug condition. This system creatively combines the telecentric imaging model and the Scheimpflug condition on the basis of structure light stereoscopic vision, having benefits of a wide measurement range, high accuracy, fast speed, and low price. The system measurement range is 20 mm×13 mm×6 mm, the lateral resolution is 20 µm, and the practical vertical resolution reaches 2.6 µm, which is close to the theoretical value of 2 µm and well satisfies the 3D measurement needs of micro components such as semiconductor devices, photoelectron elements, and micro-electromechanical systems. In this paper, we first introduce the principle and structure of the system and then present the system calibration and 3D reconstruction. We then present an experiment that was performed for the 3D reconstruction of the surface topography of a wafer, followed by a discussion. Finally, the conclusions are presented.