PURPOSE The purpose of this study was to determine the testability of the "Co or Vision Testing Made Easy" color vision test, marketed as a screening test for young children, in a population of individuals with mental retardation. The test uses simple geometric figures that are easily identified. Previously, the test has demonstrated validity as a measure of color deficiency. METHODS The test...

purpose: to report a case of xerophthalmia after bariatric surgery. case report: a 24- year -old man presented to the eye clinic with a 4 -month history of irritable gritty eyes. he complained from night blindness, too. he was being treated for dry eye with artificial tears and ophthalmic ointments during the last month without any significant improvement. his vision was 20/20 unaided in both e...

We compared electrophysiological responses [pattern-ERG (PERG) and VEP] and psychophysical measures to color stimuli to separate different forms of anomalous color vision. PERG and VEP were recorded from seven normals and 14 subjects with congenital color vision deficiencies. Stimuli were color checkerboards with 0.5 deg check size, phase reversing at 34 rev/sec. The luminances of the red and g...

Three-dimensional (3D)position estimation using a single passive sensor, particularly vision, has frequently suffered from unreliability and has involved complex processing methods. Past research has combined vision with other active sensors in which the emphasis has been on data fusion. This paper attempts to integrate multiple passive 3D cues camera focus, camera vergence and stereo disparity...

Uncorrected vision may present a significant barrier to educational mobility in poor communities in low and middle income countries. Focusing on the case of rural Northwest China, we analyze the Gansu Survey of Children and Families (2,000 children; 100 rural villages) and the Gansu Vision Intervention Project (a randomized trial; 19,185 students, 165 schools, two counties). Four main findings ...

Techniques that involve the use of comb-filtered spectra to study human colour vision have been developed in previous work (Bonnardel, V., Bellemare, H., Mollon, J.D., 1996. Measurements of human sensitivity to comb-filtered spectra, Vision Research 36, 2713-2720; Bonnardel, V., Ruderman D.L., Barlow, H.B., 1997. A fast determination of the Spectral Modulation Sensitivity Function: a comparison...

Computer vision and robotics suffer from not having good tools for manipulating three-dimensional objects. Vectors, coordinate geometry, and trigonometry all have deficiencies. Quaternions can be used to solve many of these problems. Many properties of quaternions that are relevant to computer vision and robotics are developed. Examples are given showing how quaternions can be used to simplify ...