Related Experiment Video
Updated: Aug 17, 2026

Interfacial Molecular-level Structures of Polymers and Biomacromolecules Revealed via Sum Frequency Generation Vibrational Spectroscopy
Published on: August 13, 2019
Polar value analysis of refractive data
1Department Ophthalmology, Arhus University Hospital, Arhus, Denmark. RC.POST.173@aaa.dk
Purpose:
To demonstrate the use of polar value analysis of surgically induced astigmatism (SIA).
Setting:
Department of Ophthalmology, Arhus University Hospital, Arhus, Denmark.
Methods:
Univariate polar value analysis of SIA was demonstrated for a single patient and for aggregate data. Bivariate polar value analysis was performed for aggregate data.
Results:
The meridional polar value AKP expresses the surgically induced flattening, while the oblique polar value AKP(+45) indicates the torque. This pair of polar values characterizes a regular astigmatism completely. In bivariate polar value analysis, the average SIA is the combined mean for AKP and AKP(+45), while the spread is a confidence area delineated by an ellipse.
Conclusions:
Univariate and bivariate polar value analyses, together with the surgically induced change in spherical equivalent power, yield an exact description of surgically induced change following refractive procedures.
Related Concept Videos
Measuring Reaction Rates
Polar Coordinates
Graphs of Polar Equations
Polar Equations of Conics
Polar Coordinate System
Polar Coordinates: Problem Solving

