Razer markets smart glasses.

The Anzu has glasses that can filter blue light from smartphone and computer screens, according to the manufacturer.

The glasses also contain a microphone and speakers in the frame.

The glasses, which can also serve as sunglasses with replacement lenses, can be connected to another device via Bluetooth.

Razer promises that the glasses can be used for five hours on a full battery.

The gadget from the American-Singaporean manufacturer will cost 209.99 euros.

The company is not the first to present such glasses.

For example, Bose previously marketed audio sunglasses.

Other companies are also working on smart glasses.

The company behind Snapchat presented sunglasses with a camera.

Analysts suspect that smart glasses will become the successors to smartphones.

The role of blue light on sleep rhythm is still unclear

Razer focuses with its blue light filter on people who use a lot of screens, such as gamers or night owls.

Light influences the biological clock: it is why people automatically tire in the evening and wake up at sunrise.

The precise influence of the blue light from smartphones and computer screens on the sleep rhythm is still unclear.

That's because what's on screen - finishing stressful work, watching an action movie, arguing on Twitter - can also affect sleep rhythm.

On the other hand, a blue light filter can provide psychological peace of mind.

With a lot of screen use, it therefore contributes to a day-and-night rhythm.

See also: NOWchecks: Why Your Phone's Night Mode May Not Help You