Fast Scanning Time

In most optical 3D scanning methods, a large number of re-focused images need to be taken. Confocal microscopy and white light interferometry are examples of such approaches.

 For these methods, it is quite common to have one image per vertical resolution element. Consequently, a lengthy scanning process of capturing 128 images will result in constructing a 3D map with only 7-bit depth resolution.

 Coherent holography, on the other hand, can provide very high-resolution depth maps at a fast scanning pace. For example, we can create 10-bit depth maps at a frame-rate of the digital camera being used. Although the height measurement range in 3D space is very high (e.g. 20mm), our invention requires only a single image to reconstruct a 3D depth map. This method reduces system processing time dramatically and as result, can be installed where fast-moving targets need to be precisely measured.

 Until recently, this advantage of coherent digital holography had been outweighed by its disadvantage: huge speckle-noise.  However, Angstrom Vision invented new image-processing algorithms that are proven to be highly efficient for speckle-noise suppression.