One-twelfth of the students felt eye sore because of reading under too strong or too dim light.

十二分之一的同学因为在强光下看书，在弱光下看书而眼睛疼痛。

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This light is too dim to read by.

这光线太暗，看不了书。

《牛津词典》

Speaking of sensors, we experienced problems with the auto-brightness setting, which would dim the screen too much in low light, while behaving normally in daylight.

说到传感器，我们发现一个亮度自动调节的问题，在日光下屏幕亮度自动调节正常，但在暗环境中屏幕会自动变得过于昏暗。

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While red dwarfs are the most common type of star in the Milky Way galaxy, they often do not show up in astronomical surveys because they are too dim in visible light.

MSN: 'Impossible' stars found in our galaxy - Technology & science - Space - Space.com | NBC News