Shape-from-Focus for Real-Time Terahertz 3D Imaging

Thanks to significant advances in real-time terahertz imaging in term of resolution and image quality, adapting and extending optical methods for 3D imaging at the millimetre scale is now promising. The Shape from Focus (SFF) algorithm is a post-processing tool used in optical microscopy to reconstruct the external shape surface of a bended object. A stack of images at different distance object-lens are implemented in this algorithm that elegantly takes advantage of the very short imaging system depth of field as the third dimension. In this letter, we propose an application of this algorithm in active and real-time terahertz imaging. We notably achieve the experimental reconstruction in 3 dimensions with terahertz waves and pave the route for a new vision system.