Linked Life Data

10023480

Source:http://linkedlifedata.com/resource/pubmed/id/10023480

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1999-3-8
pubmed:abstractText
The visual axis is the ray path from the fixation point to the fovea by way of the nodal points. Such a ray path does not exist in unaccommodated vision when the fixation point does not coincide with the far point of the eye because of induced or natural defocus. Nevertheless an approximation to the visual axis can be obtained by the position of a small pupil close to the cornea for which a bichromatic vernier target appears correctly aligned. When the visual axis is determined, an eye rotation from the visual fixation position must occur, which is reversed upon removing the small pupil. Upon engaging in any experiments for which the visual axis is then used as a reference, there is an error in this reference position. We develop simple paraxial equations to estimate this error. We show that these equations have good accuracy. The error associated with locating the visual axis at the cornea is 0.002 mm per dioptre of defocus, which is small enough to be ignored.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0275-5408
pubmed:author
pubmed:issnType
Print
pubmed:volume
18
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
463-7
pubmed:dateRevised
2006-11-7
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Errors in determining the direction of the visual axis in the presence of defocus.
pubmed:affiliation
School of Optometry, Queensland University of Technology, Kelvin Grove, Australia.
pubmed:publicationType
Journal Article