Search results for " Imaging systems"
showing 3 items of 3 documents
Three-dimensional multiple-particle tracking with nanometric precision over tunable axial ranges
2017
The precise localization of nanometric objects in three dimensions is essential to identify functional diffusion mechanisms in complex systems at the cellular or molecular level. However, most optical methods can achieve high temporal resolution and high localization precision only in two dimensions or over a limited axial (z) range. Here we develop a novel wide-field detection system based on an electrically tunable lens that can track multiple individual nanoscale emitters in three dimensions over a tunable axial range with nanometric localization precision. The optical principle of the technique is based on the simultaneous acquisition of two images with an extended depth of field while …
Multispectral image denoising with optimized vector non-local mean filter
2016
Nowadays, many applications rely on images of high quality to ensure good performance in conducting their tasks. However, noise goes against this objective as it is an unavoidable issue in most applications. Therefore, it is essential to develop techniques to attenuate the impact of noise, while maintaining the integrity of relevant information in images. We propose in this work to extend the application of the Non-Local Means filter (NLM) to the vector case and apply it for denoising multispectral images. The objective is to benefit from the additional information brought by multispectral imaging systems. The NLM filter exploits the redundancy of information in an image to remove noise. A …
Non conventional Imaging Systems for 3D Digitization of transparent and/or specular manufactured objects
2013
International audience; 3D scanning has been investigated for several years and most of the proposed approaches assume a diffuse or near diffuse reflectance of the object's surface, also called cooperative surfaces. For the case of "non cooperative surfaces", such as transparent objects or mirror-like surfaces, usually, a thin layer of powder is sprayed onto the object surface (to make it opaque and diffuse) prior to its digitization. This extra step is troublesome, time consuming (the object needs to be cleaned afterwards), and the final accuracy is often dependent on the powder thickness and its homogeneousness. To avoid this step, various methods have been investigated over the last few …