What is that mark on your screen?
Put the screen in full-screen white, black and grey. The mark tells you what it is. Then read whether it can be fixed, what it costs, and whether warranty covers it.
White screen⛶ Full screen
On whitedark spots, pressure marks, lines
On blackbright dots, backlight bleed, glow
On red, green, bluedead or stuck pixels, colour lines
Or answer three questions
1. What do you see?
2. Is it there on every colour?
3. Does it change when you tilt the lid or plug in an external monitor?
Most searched symptoms
White spot on screenA white spot on a screen screen that glows on black is the backlight coming through where it should not: the reflector or diffuser sheet behind the LCD has a pressure dent, or a backlight LED sits too close to the panel.Depends — see testWhy is there a purple line on my iPhonePurple vertical lines on an iPhone screen are almost always the display itself: the flex connector between the panel and the board has lifted (often after a drop or a swollen battery pushing from behind), or a row or column driver on the panel has failed.Depends — see testWhy is my laptop screen green?A green tint over the whole screen — or a screen that is entirely green — almost always means one colour channel is missing or one is stuck on, and that is a signal problem, not a panel defect: the display cable through the hinge has worked loose or a pin has failed, a graphics driver has misconfigured the colour output, or a colour filter (Night Light, a colour profile, a screen-reader filter) is on.FixableDisplay flickeringA flickering screen screen is the signal, the refresh rate or the backlight.FixableBlack spot on MacBook screenA black spot, black dot or dark patch on a MacBook screen that stays put on every colour is in the display itself: a cluster of dead pixels, a crack in the LCD layer under intact glass, or pressure damage where the lid was closed on something.Not fixable — new panelLenovo laptop display issuesLenovo laptop screen problems fall into a short list, and each one has its own page: a black or white spot (pixels, pressure, backlight), a line (panel connector, cable, or graphics), a colour cast (settings or panel ageing), flicker (settings, cable, or connector), burn-in ghosts (OLED ageing), a blurry image (settings), half the screen blank (panel driver), or touch that stops responding in one area (digitiser).Depends — see testLaptop screen issuesLaptop screen problems fall into a short list, and each one has its own page: a black or white spot (pixels, pressure, backlight), a line (panel connector, cable, or graphics), a colour cast (settings or panel ageing), flicker (settings, cable, or connector), burn-in ghosts (OLED ageing), a blurry image (settings), half the screen blank (panel driver), or touch that stops responding in one area (digitiser).Depends — see testBright spot on iPhone screenA white spot on an iPhone screen that glows on black is one of two things.Depends — see testGalaxy S8 screen linesA line on a Galaxy S8 screen is almost always the display itself: the flex connector between the panel and the board has lifted (often after a drop or a swollen battery pushing from behind), or a row or column driver on the panel has failed.Depends — see testNote 9 screen color issueA phone screen that has turned off-colour — the whole screen, not a patch — is one of four things, in order of likelihood: a colour setting (Eye comfort / Night Light / a colour filter under Accessibility / a wallpaper-based theme), an OLED panel ageing or damaged so its colour balance has drifted (a cast that is worse at low brightness), a lifted display connector after a drop, or liquid in the display.FixableYellow spot on my phone screenA yellow spot on a phone screen is heat or adhesive: on an OLED the organic layer has aged where the phone runs hottest (the bottom, near the charging port and the processor), and on an LCD the optical adhesive between glass and panel has yellowed or separated.Depends — see testBlack spot on screenA black spot on a screen screen that shows on white and vanishes on black is inside the panel: a cluster of dead pixels (a sharp-edged tiny square), a pressure mark (soft-edged, where something pressed the panel), or dirt under the glass (moves if you press gently, on tablets and monitors only).Depends — see testDark spot on screenA dark spot on a screen screen that shows on white and vanishes on black is inside the panel: a cluster of dead pixels (a sharp-edged tiny square), a pressure mark (soft-edged, where something pressed the panel), or dirt under the glass (moves if you press gently, on tablets and monitors only).Depends — see testLaptop screen green tintA laptop screen that has gone green all over is the signal or the panel's colour balance, and it is usually the signal.FixablePhone screen turning greenA phone screen that has turned green — the whole screen, not a patch — is one of four things, in order of likelihood: a colour setting (Eye comfort / Night Light / a colour filter under Accessibility / a wallpaper-based theme), an OLED panel ageing or damaged so its colour balance has drifted (a green cast at low brightness is the classic AMOLED sign), a lifted display connector after a drop, or liquid in the display.FixableWhy do computer screens look weird on cameraA screen looks weird on camera — wavy rainbow bands, rolling dark stripes, flicker — for two reasons, and neither is a fault.FixablePhone display problemPhone screen problems fall into a short list, and each one has its own page: a black or white spot (pixels, pressure, backlight), a line (panel connector, cable, or graphics), a colour cast (settings or panel ageing), flicker (settings, cable, or connector), burn-in ghosts (OLED ageing), a blurry image (settings), half the screen blank (panel driver), or touch that stops responding in one area (digitiser).Depends — see testWhite spot on Lenovo laptop screenOn Lenovo ThinkPad and IdeaPad screens this is a known pattern: a bright, soft-edged white spot that shows on dark backgrounds, most often near the lower half of the screen.FixableGrainy screen protectorA grainy, sparkly or slightly rainbow look after fitting a screen protector is the protector, not the screen: matte protectors scatter light and make white look like fine sand, and a cheap glass protector with a thick adhesive layer adds a faint moiré against the pixel grid.FixableGreen dots on laptop screenGreen dotss on a laptop screen are single green sub-pixels stuck on, or a small area where pressure has damaged the OLED layer.Depends — see testLaptop screen purpleA laptop screen that has gone purple all over is the signal or the panel's colour balance, and it is usually the signal.FixableS8 black dot on screenA black dot on a phone screen that shows on white and vanishes on black is inside the panel: a cluster of dead pixels (a sharp-edged tiny square), a pressure mark (soft-edged, where something pressed the panel), or dirt under the glass (moves if you press gently, on tablets and monitors only).Depends — see testScreen burnScreen burn-in is a permanent ghost of something that sat still on the screen for a long time — the navigation bar, the keyboard, a game HUD, a clock.Not fixable — new panelWhy is my phone screen green?A green tint over the whole phone screen — or a screen that goes fully green — has two very different causes.Depends — see test
All symptoms by device: TV screen problems (3) · Phone screen problems (54) · Laptop screen problems (24) · MacBook screen damage (3) · Monitor and screen tests (13) · Any screen (23).
Rule of thumb
| You see | It is | Fixable? |
|---|---|---|
| Black dot, same on every colour | Dead pixels or a crack | No — panel |
| Coloured dot, same on every colour | Stuck pixel | Often — pixel fixer |
| Soft white glow on black only | Loose backlight reflector | Yes — repair shop |
| Dark smudge on white only | Pressure mark | No — panel |
| One-pixel line, all colours | Panel driver | No — panel |
| Line or flicker that changes with lid angle | Display cable | Yes — cable |
| Bright edges on black | Backlight bleed | Cosmetic |
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