All screen test tools

    Ring Light Online

    Use a screen as a simple fill light. Switch between a full field, a circular ring and a rectangular frame; adjust the dark centre, light width, colour tone and output intensity.

    • Full-screen, circular and rectangular light layouts
    • Adjustable dark centre and light width
    • Warm, neutral and cool colour tones
    • Save settings locally and optionally keep the screen awake
    Light layout
    Colour tone

    Changes page colours only; set hardware brightness on your device.

    The dark centre does not show other apps. Use side-by-side windows or a second screen.

    Keeping the screen awake is unavailable in this browser.

    Changes page colours only; set hardware brightness on your device. The dark centre does not show other apps. Use side-by-side windows or a second screen.

    How to use

    1. Place this screen near the camera. Use a second display or put the light and meeting windows side by side on one screen.
    2. Choose a layout and tone, then adjust the dark centre, light width and page output intensity. Observe the result in your meeting app.
    3. Enter fullscreen for a larger light area. Hide the controls when ready; the show and exit buttons remain available.
    4. Save settings only if you want to reuse them in this browser. Keeping the screen awake is a separate, optional request; request it again after returning from the background if needed.

    What to keep in mind

    This changes page colours, not hardware brightness or a calibrated Kelvin temperature. Lighting depends on your display, distance, room and camera; results are not guaranteed. The dark centre is opaque and does not reveal another app. Use side-by-side windows or a second screen to keep a meeting visible. No camera is requested. Wake Lock may be unsupported, denied or released by the system; the tool never automatically requests it again. Saved settings stay in this browser when storage is available.

    Questions

    Can I see my meeting through the centre?

    No. The centre is a dark part of this page, not a transparent hole into Zoom or Teams. Put the windows side by side or use a second display.

    Does the intensity slider change my screen brightness?

    It changes the RGB colour drawn by this page. Set the actual display brightness using your device controls. Warm and cool tones are visual presets, not measured colour temperatures.

    Why did keeping the screen awake stop?

    The browser or system can release Wake Lock, especially in the background or under power restrictions. Its status is shown. Returning here does not automatically request it again; choose the button if you want to retry.

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