1. Swipe down from the Notification bar, then select the settings icon Settings icon.
 
2. Select Display, then select Comfort view.

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3. To enable comfort view, select the Use Comfort view switch.

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4. To manually adjust the level of blue light, select and drag the Blue light filter slider to the left or the right.

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5. Select the Black & white switch to view your device's screen in black and white.

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