Time to replace the spherical equivalent with the average paraxial lens power

While for the ApP , the average is the average of orthogonal and oblique paraxial rays, that is, ApP =average orthogonal and oblique paraxial power F¯ApP(orthogonal+oblique), F¯ApP(orthogonal+oblique)=C14+C14+C2−C14, ApP=F¯ApP(orthogonal+oblique)=C14+C24. [...]the ApP is equal to half the SE if calc...

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Bibliographic Details
Published in:BMJ open ophthalmology 2023-06, Vol.8 (1), p.e001340
Main Author: Kaye, Stephen B
Format: Article
Language:English
Subjects:
Approximation
Editorial
Lenses
Optics and Refraction
Refraction, Ocular
Visual acuity
Citations: Items that this one cites
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Summary:While for the ApP , the average is the average of orthogonal and oblique paraxial rays, that is, ApP =average orthogonal and oblique paraxial power F¯ApP(orthogonal+oblique), F¯ApP(orthogonal+oblique)=C14+C14+C2−C14, ApP=F¯ApP(orthogonal+oblique)=C14+C24. [...]the ApP is equal to half the SE if calculated in cross cylinder form, that is, ApP=SE2. If a refractive error, however, does comprise a true spherical component, then the average of that component is of course the sphere. [...]for a refractive power that contains a sphere, the ApP=Sphere+C4 and the SE=Sphere+C2 and the difference between the ApP and SE is equal to C4 . The ApP as a scalar measure is more inclusive and appears to be associated with better visual acuity than the SE, although further clinical trials are needed particularly in different age groups and conditions.
ISSN:2397-3269
2397-3269
DOI:10.1136/bmjophth-2023-001340