[multiple comments to be separated?] Section 2.4: language

[allanj-uaag]

from https://lists.w3.org/Archives/Public/public-low-vision-comments/2016AprJun/0003.html
Section 2.4

· Should say factors that impact on visual functioning rather than categories of visual impairment.
· Replace ‘light sensitivity’ with ‘sensitivity to glare’.
· Add ‘visual fatigue’ and ‘visual clutter’ to the list of factors that impact on visual functioning.

Section 2.4.1
· Needs more precise definition of visual acuity. Suggestion: Visual Acuity is a measure of the finest detail a person can perceive.
· 'Therefore, some people will have blurry vision (low visual acuity) no matter what.' This statement is not accurate and therefore not helpful, and should not be included.

Section 2.4.2
· ‘Light sensitivity’ should be changed to ‘Glare sensitivity’. (Refer to attached article, A review of the impact of glare and fatigue on visual function, p54)

Section 2.4.3
· Contrast sensitivity definition needs to be more succinct. Suggestion –‘Contrast sensitivity determines the retina's ability to detect subtle differences in brightness or shading of grey between targets and their backgrounds’.
(source: Fundamentals for Ophthalmic Technical Personnel by Cassin p167)

Section 2.4.4
· Poor definition of Visual field. Suggestion: “The visual field is a map of the extent of visual space seen without moving the eye” (Cassin p.219)
· Should be 130 degrees vertical not 150 degrees.
· Last paragraph of this section. ‘For example, when a person with low visual acuity….to reduced visual acuity’. This doesn't make sense and is not true.'

Section 2.5: Functional Vision
· Paragraph after Issue 2. Other factors – such as inflammation, medication, fatigue, environment, and task (add in lighting) – influence a person's effective (replace with functional) vision in a given situation.
· Environmental factors include:
Add in ‘visual clutter’