Sometimes AMOLED display turns green or purple (tinted) I am using Samsung Galaxy A5 A500G since last month, but sometimes while using the phone, the display turns slightly green or purple (tinted) in shade. But as soon as I adjust the screen brightness, the display becomes normal.

Is it a problem?
Is it a problem ?


Not if it vanishes by increasing brightness a bit or moving out of shade. It is a problem if you see this with normal day time brightness

Why does it happen?

Samsung AMOLED displays are based on PenTile technology and manufactured by Nouvoyance ( Nouvouyance partners with Samsung and  also supplies Pentile displays to other OEMs as well). Instead of the conventional (called Real Stripe) OLED displays pixel pattern of RGB , PenTile uses RGBW, which cuts power consumption to half for the same brightness and hence longer screen life as well


This technology has   disadvantage of  colours looking grainy, more so warmer colours. This effect is visually more pronounced in low brightness


(OR)


Red LEDs consume least power for same brightness followed by Green and Blue, so when the screen is in low brightness red is comparatively brighter and gives a pinkish/ greenish hue. This is considered to be a feature of Nexus 6 and not a bug


Any /combination of these two factors makes the color combination look tinted and variously described as purple, brown or pink. This should be the main reason for your observation (other being a problem with screen or screen digitizer, if it is very pronounced).