Bias lighting behind a wall-mounted TV

Watching a bright screen in a dark room makes your pupils keep adjusting between the picture and the blackness around it. A gentle glow on the wall behind the TV — bias lighting — evens that out. It's one of the cheapest upgrades there is, and wall-mounted TVs suit it perfectly.

What it does

• Less eye fatigue during long, dark-room viewing.
• Blacks look blacker. With a lit surround, your eyes judge the screen's dark areas as darker. LCD "grey" blacks benefit most.
• The TV looks like it floats. A soft halo hides the bracket shadow.

What it doesn't do

It doesn't fix daytime glare, and coloured or flashing strips are decoration, not bias lighting.

Choose the right light

• Colour temperature: 6500K ("D65"). That's the white point video is mastered to. Warmer or cooler light shifts how you perceive the picture's colours.
• High CRI (90+) so the white is clean.
• Dimmable. The glow should be subtle — roughly a tenth of the screen's peak brightness. If you notice it during a film, it's too bright.
• Plain white beats RGB for picture quality. Colour-changing strips are fun; use white for films.

Where the strip goes

On the back of the TV, a couple of inches in from the edge, facing the wall — never facing forward.

• All four sides gives an even halo. Three sides (not the bottom) works above a console.
• Keep it far enough from the edge that you can't see individual LEDs from the side.
• The gap to the wall matters: at 1 inch (slim mount) the glow is a tight, bright line; at 2–3 inches it spreads into a soft halo. A diffuser channel helps with very slim mounts.
• Clean the plastic with rubbing alcohol first so the adhesive holds; press it down around corners or use corner connectors.

Power

• USB-powered strips plug into the TV's USB port and switch on and off with the TV. Simplest, and no extra cable down the wall. Check the port can supply enough current; long strips on big TVs may need a separate adapter.
• Adapter-powered strips need an outlet behind the TV — one more reason to plan a duplex outlet there. See where to put the outlet.

Don't run the strip's thin power lead inside the wall; keep it behind the TV.

Wall colour

Bias light reflects off the wall, so the wall tints it. White, grey and neutral walls work best. A strongly coloured wall colours the halo, which then skews your sense of the picture.

Screen-matching kits

Some kits use a camera or an HDMI box to make the lights follow the on-screen colours. They're immersive for games and sport, and distracting for drama. Many let you switch to plain white.

Brick, stone and textured walls

Textures look dramatic with grazing light from behind a TV. On dark brick, the halo will be dim; a brighter strip helps.

With a full-motion mount

The halo changes as the TV moves away from the wall. Leave slack in the strip's power lead for the arm's travel.

Smart home

USB strips need nothing. Mains-powered strips can go on a smart plug or the strip's own app to follow a "movie" scene with the room lights.

Other gentle options

A dimmed lamp behind or beside the TV — not reflecting in the screen — does much the same job.

If you'd like a strip fitted while the TV is off the wall, mention it in your booking notes and have the kit ready; it's far easier before the TV is hung.