An intrinsic property of real aperture based imaging is the blurring of an observation due to defocus. There are two major aspects related to the defocus blur present in the image. The first aspect is based on use of the defocus blur for estimating the depth in the scene. The other aspect relates to restoration of the image. This problem manifests itself as a challenging blind, space varying de...

Blur detection is affected by retinal eccentricity, but is it also affected by attentional resources? Research showing effects of selective attention on acuity and contrast sensitivity suggests that allocating attention should increase blur detection. However, research showing that blur affects selection of saccade targets suggests that blur detection may be pre-attentive. To investigate this q...

Combined manipulation of blur, line length and contrast reveal two distinct processes involved in curvature detection. When line length is small relative to blur, thresholds are almost directly proportional to blur and independent of line length. When line length is large relative to blur thresholds are directly proportional to line length and independent of blur. The aspect ratio (line length/...

Although blur adaptation in myopia has been investigated, knowledge regarding its effect on blur sensitivity remains unknown. In the present study, changes in three blur thresholds (i.e., noticeable, bothersome, and non-resolvable blur) were assessed monocularly after 1h of blur adaptation in myopes. A Badal optical system was used to present either an isolated 20/50 Snellen E or 20/50 lines of...

This paper describes a silicon retina that measures image sharpness. The idea is to use this sensor in the image plane of an autofocusing camera system [3]. The chip has 25x26 pixels, each (60μm)2, is fabricated on a (2.2mm)2 1.2 μm CMOS process, and consumes 100 μA with 5 V supply. 1. ALGORITHM Image defocus corresponds to a filtering operation on the image with a circular cookie-cutter kernel...