Why is the Sky Blue?

Hint: it’s not the reflection of the water, and it may cause fatigue and sore eyes.

Light is made of Electromagnetic waves (EM waves) that emit energy and it’s this energy which we perceive as light. These waves come in different wavelengths and are the different colours of light we perceive.

Blue light is one of the types of light that form the white light we get from the sun, together with red, orange, yellow, green, violet and indigo – also known as the visible EM spectrum. Past indigo, we have UV light (which can’t be seen by the human eye). The energy of these waves increases as we go towards UV light, making blue light one of the highest intensity types of visible light.

The wavelength of blue light waves is so small they collide with air molecules more than any other colour and get scattered everywhere – that’s what makes the sky blue!

But what has this got to do with me?

Your body uses this blue light from the sun to discern the difference between day and night and regulate your sleep cycle. It also suppresses the secretion of melatonin – produced at night to help prepare our bodies for sleep. Because of this, blue light can fool our brains into thinking we should stay awake.

And what has this got to do with Optoma?

Optoma’s Creative Touch interactive displays reduce eyestrain and tiredness by minimising blue light output.  They are TÜV Certified as Low Bluelight Content, meaning that TÜV Rheinland* has tested the blue light emitted and found the product emits no hazardous UV light, in addition to the blue light content constituting no more than 20% of the total light spectrum emitted from the screen.

A new study by researchers in Amsterdam stated that people who switched their screens to low blue light reported their sleeping patterns were significantly improved.

In short, the sky is blue because the short-wavelength, high energy blue light scatters more easily than other visible light, and you should turn on blue light filters when available – you might sleep better!

*TÜV Rheinland is the independent body and world leader in product testing and certification.

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