Skip to Content

Photonic Crystals Reinvent Tungsten Light Bulbs

Photonic crystals of tungsten emit visible light but without the same wasteful emission of infrared, say researchers aiming to reinvent the light bulb

Photonic crystals are nanoscopic structures designed to channel light of specific wavelengths while blocking other wavelengths. 

This ability to control and filter light with great efficiency makes them hugely useful for applications such as increasing the efficiency of photovoltaic cells by absorbing light at certain optimal wavelengths. 

Today, Sergei Belousov and buddies at the Kintech Lab in Moscow and a number of friends at the GE Global Research Center in New York state,  say they have another application for photonics crystals. They’ve worked out how photonic crystals can dramatically improve the light emitting efficiency of tungsten in the hope of reinventing the light bulb. 

Tungsten bulbs have had a bad press, to say the least. Tungsten has a high melting point (3695 K) and so can be heated until it glows without melting. The problem is that only 5 per cent of the light it emits is visible, the rest being infrared, which simply goes to waste.   With an efficiency of only 5 per cent, tungsten bulbs have rapidly fallen out of favour.

The question Belousov and co set out to answer is whether they can engineer the nanostructure of tungsten to create a photonic crystal that emits visible light while suppressing the emission of infrared light.

They theoretically studied the properties of several structures, such as nanoscopic tungsten log piles and spheres embedded in another medium. While tungsten log piles make little difference, tungsten spheres just a fraction of a micrometre in radius do just the job, emitting light mainly in the visible region of the spectrum.

Belousov and co then tested their idea by making a tungsten photonic crystal of the required design and measuring the amount of light it emits at different frequencies. They say the new structure emits far less infrared light and has an efficiency of 15 per cent, significantly higher than the bulk material.

That’s a significant improvement and improvements on this will surely be possible. But whether it will be enough to trigger a tungsten revolution in light bulbs is open to question. The current generation of compact fluorescent bulbs can match the light output of a 100 Watt tungsten bulb using less than 30 Watts and LED lights can do it using less than 20 Watts. 

If Belousov and co want to put tungsten back into light bulbs, they’ll have to beat some stiff opposition first.

Ref: arxiv.org/abs/1212.3451: Using Metallic Photonic Crystals As Visible Light Sources

Keep Reading

Most Popular

A Roomba recorded a woman on the toilet. How did screenshots end up on Facebook?

Robot vacuum companies say your images are safe, but a sprawling global supply chain for data from our devices creates risk.

A startup says it’s begun releasing particles into the atmosphere, in an effort to tweak the climate

Make Sunsets is already attempting to earn revenue for geoengineering, a move likely to provoke widespread criticism.

10 Breakthrough Technologies 2023

Every year, we pick the 10 technologies that matter the most right now. We look for advances that will have a big impact on our lives and break down why they matter.

These exclusive satellite images show that Saudi Arabia’s sci-fi megacity is well underway

Weirdly, any recent work on The Line doesn’t show up on Google Maps. But we got the images anyway.

Stay connected

Illustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at customer-service@technologyreview.com with a list of newsletters you’d like to receive.