Evaluating the quality of EDOF in camera phones

Extended Depth of Focus technologies are well known in the literature, and in recent years this technology has made its way into camera phones. While the fundamental approach might have significant advantages over conventional technologies, often in practice, it turns out the results can be accompanied by undesired artifacts that are hard to quantify. In order to conduct an objective comparison with the conventional focus technology, new methods need to be devised that are able to quantify not only the quality of focus but also the artifacts introduced by the use of EDOF methods. In this paper we propose a test image and a methodology to quantify focus quality and its dependence on the distance. Our test image is created from a test image element that contains different shapes to measure frequency response.