Screen Brightness Test
Adjust the slider to test different brightness levels on your display.
100%
What to Check
- Backlight uniformity - look for uneven brightness across the screen
- Backlight bleed - bright spots around edges, especially at low brightness
- Minimum brightness - how dark can your screen get?
- Contrast - can you still see details at low brightness?
How to Use This Test
- Use the slider or preset buttons to adjust the simulated brightness level from 0% to 100%.
- Observe the white display area at each level, paying attention to uniformity and any visible artifacts.
- Test at low levels (0-20%) in a dark room to check for backlight bleed around the screen edges.
What This Test Checks
This screen brightness test helps you evaluate several key display characteristics that impact your viewing experience.
- Backlight uniformity across the entire display panel
- Backlight bleed and light leakage around edges and corners
- Minimum brightness capability for comfortable use in dark environments
- Contrast retention at various brightness levels
Troubleshooting
If you're having issues with this test:
- Make sure your browser is not applying any zoom or accessibility filters that could affect the display.
- Disable any blue light filter or night mode software for accurate results.
- Test in a controlled lighting environment -- a dark room is ideal for detecting backlight bleed.
- If the display area does not change, try refreshing the page or using a different browser.
Frequently Asked Questions
How do I check if my screen brightness is even?
Set the brightness slider to a low level (10-20%) and look at the display in a dark room. Uneven brightness, known as backlight bleed, will appear as bright spots or patches around the edges of the screen.
Why does my screen look different at low brightness?
At low brightness levels, LCD panels can exhibit reduced contrast and color shifting. This is normal behavior, but excessive banding or color distortion may indicate a display issue or a need for calibration.
What is backlight bleed and is it a defect?
Backlight bleed is light leaking around the edges or corners of an LCD screen, most visible on dark content at high brightness. Minor bleed is normal on most LCD panels, but severe bleed that distracts during normal use may warrant a replacement.
Can this test damage my screen?
No, this brightness test is completely safe. It simply changes the CSS opacity of an on-screen element to simulate brightness levels. It does not alter your actual display hardware brightness settings.
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