Panel types: IPS, VA, OLED and Mini-LED

Two families: filtered light and emitted light

All current monitors belong to one of two families. In a liquid-crystal display (LCD), a white backlight shines permanently behind the panel; each sub-pixel is a shutter of liquid crystals that lets more or less of that light through a red, green or blue filter. In an OLED display there is no backlight: each sub-pixel is a diode that emits its own light and can be switched off completely.

Everything follows from this difference. An LCD shutter never closes perfectly, so black is a dark grey whose depth depends on the type of crystal alignment: that is the difference between IPS, VA and TN. An OLED pixel that is off is black, full stop.

IPS: the reference for work

In an IPS panel (in-plane switching) the crystals rotate parallel to the surface. Light leaves the panel almost identically in all directions: colours and brightness barely change when you look at the screen from the side or, more to the point at a desk, when you look at the corners of a large screen from the centre.

The price is contrast. A standard IPS panel reaches 1000:1 to 1300:1: in a dark room its black is visibly grey, and its corners can show a silvery glow at an angle (“IPS glow”). The IPS Black generation, introduced in 2022, doubles that figure to 2000:1, and its most recent versions reach 3000:1, with the same angular stability.

Fast IPS panels reach response times of a few milliseconds without visible artefacts, which makes the technology suitable for games as well. For text, spreadsheets, code and colour work, IPS remains the choice by default: nothing else is as uniform and as predictable.

VA: contrast first

In a VA panel (vertical alignment) the crystals stand perpendicular to the surface at rest and block the light much better: native contrast of 3000:1 to 5000:1. Blacks are deep, and films or games with dark scenes gain visibly over IPS.

Two weaknesses come with it. Transitions between dark shades are slow on many VA panels, which leaves a dark trail behind moving objects (“black smearing”); the best recent models have largely corrected this, the cheap ones have not. And gamma shifts with the viewing angle: on a large flat VA screen the edges look slightly washed out compared with the centre. This is one reason why wide VA monitors are almost always curved.

VA offers the best image for the money in curved ultrawide and large formats intended for games and video. For text and colour-critical work, IPS is the safer choice.

TN: what remains of it

TN (twisted nematic) was the first mass-market technology: fast and cheap, with poor colours and viewing angles so narrow that the top of the screen differs from the bottom. It survives in a few monitors for competitive play at 360 Hz and above. There is no reason to choose it for anything else.

OLED: every pixel is its own light

An OLED monitor has no contrast limit to speak of, since black pixels are off, and its pixels change state in about a tenth of a millisecond, a hundred times faster than the best LCDs. Motion is as clean as the refresh rate allows, dark scenes are free of halos, and viewing angles are excellent. For games and video, nothing matches it.

Three reservations concern desk use.

Burn-in. Organic diodes wear with use, and elements that stay in place for thousands of hours (a taskbar, a toolbar, the borders of a window) can leave a faint permanent imprint. Manufacturers counter this with pixel shifting, compensation cycles and, increasingly, warranties of two or three years that cover burn-in. For a screen that displays the same interface eight hours a day, the risk remains real; read the warranty.

Text rendering. Systems smooth fonts for the red-green-blue stripe of LCDs. OLED monitors use other sub-pixel layouts, a triangle on QD-OLED, four sub-pixels including a white one on WOLED, and letters show slight coloured fringes on their edges.

The effect is visible at 110 PPI (27-inch 1440p, 34-inch ultrawide) and largely disappears at 160 PPI and above (27-inch and 32-inch 4K), where the fringes fall under the limit of the eye.

Brightness on white. To protect the panel and limit consumption, OLED monitors reduce their brightness when a large part of the image is bright. A white document covering the whole screen is displayed at 250 nits or so, sufficient indoors, a little short near a window.

Mini-LED: an LCD with local dimming

Mini-LED designates a backlight made of thousands of tiny diodes grouped into zones, a few hundred to a few thousand, that the monitor dims independently behind the dark areas of the image. Placed behind an IPS or VA panel, it multiplies effective contrast and allows peak brightness of 1000 nits and more, which makes it the technology of choice for HDR in bright rooms.

Its limit is the size of the zones, far larger than a pixel: a bright object on a black background is surrounded by a halo (“blooming”), and the dimming algorithm sometimes hesitates on mouse cursors or subtitles. Many users disable local dimming for desk work and keep it for video and games. Burn-in does not exist.

Side by side

Which panel for which use

• Office work, code, dashboards: IPS, IPS Black if the budget allows and the room is dim.
• Photo, video, design: IPS with a wide, calibrated gamut (see the chapter on colour); OLED or Mini-LED for HDR grading.
• Games: fast IPS for all-round use, OLED when the budget allows, VA for contrast on a budget in curved formats.
• Films in a dark room: OLED, then VA.

The surface treatment matters too. A matte coating scatters reflections and suits offices with windows and ceiling lights; it very slightly veils the image. A glossy coating gives purer blacks and more vivid colours, and reflects every light source behind you. Choose according to the room, not the showroom.