The effect of aberrations on objectively assessed image quality and depth of focus.
The effects of aberrations on image quality and the objectively assessed depth of focus (DoF) were studied. Aberrometry data from 80 young subjects with a range of refractive errors was used for computing the visual Strehl ratio based on the optical transfer function (VSOTF), and then, through-focus simulations were performed in order to calculate the objective DoF (using two different relative thresholds of 50% and 80%; and two different pupil diameters) and the image quality (the peak VSOTF). Both lower order astigmatism and higher order aberration (HOA) terms up to the fifth radial order were considered. The results revealed that, of the HOAs, the comatic terms (third and fifth order) explained most of the variations of the DoF and the image quality in this population of subjects. Furthermore, computer simulations demonstrated that the removal of these terms also had a significant impact on both DoF and the peak VSOTF. Knowledge about the relationship between aberrations, DoF, image quality, and their interactions is essential in optical designs aiming to produce large values of DoF while maintaining an acceptable level of image quality. Comatic aberration terms appear to contribute strongly towards the configuration of both of these visually important parameters.
Department of Optics, and Optometry, and Vision Sciences, University of Valencia, Valencia, Spain.
Antonio J Del
AJ
Águila-Carrasco
School of Optometry and Vision Science, Queensland University of Technology, Brisbane, Australia.
Scott A
SA
Read
Department of Optics, and Optometry, and Vision Sciences, University of Valencia, Valencia, Spain.
Robert
R
Montés-Micó
Faculty of Fundamental Problems of Technology, Wroclaw University of Science and Technology, Wroclaw, Poland.
D Robert
DR
Iskander
D057128:Aberrometry; D000293:Adolescent; D000328:Adult; D001251:Astigmatism / Q000503:physiopathology; D003198:Computer Simulation; D057108:Corneal Wavefront Aberration / Q000503:physiopathology*; D003867:Depth Perception / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D012189:Retrospective Studies; D014785:Vision, Ocular / Q000502:physiology; D014792:Visual Acuity / Q000502:physiology; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult