Table 4. Luminance uniformity (white squares, L_min/L_max, %) of seven tablets at five different nominal brightness settings.

Measurements were made with room lights off. Device/setting combinations which do not meet the BS 4274 requirements (> 80%) are in bold.

nominal brightness setting	100%	75%	50%	25%	0%
iPad 3	84	83	80	83	82
iPad 4 #1	91	91	91	89	90
iPad 4 #2	77	77	76	77	77
iPad 4 #3	85	86	85	85	82
iPad Air 2 #1	77	78	78	77	81
iPad Air 2 #2	80	81	80	80	80
iPad Air 2 #3	85	85	86	85	88