Building an artificial window

Several years ago, I mentioned the Italian company CoeLux, which specializes in making artificial windows: light fixtures that look like sunlight in a clear blue sky.

The price of their products is apparently in the range of several tens of thousands of dollars (I’ve heard prices like $20k to 50k), which makes it out of reach for most individuals. Not many details about their invention are available either (from the promotion material: LED powered, several hundred watts of electrical power, a solid diffuse material, and a thickness around 1 meter), and I was left wondering what was the secret sauce to their intriguing technology.

The window in this photo is in fact an electrical light fixture.

The YouTube channel DIY Perks has been working on day light projects for a while now, improving at each iteration. Yesterday they published a video explaining how to build a light that seems to give very similar results as CoeLux’s product, from some basic materials that are fairly simple to find. Since their solution takes roughly the same volume, it’s tempting to think it uses the same technique

It’s extremely satisfying to finally see how this works and, despite the practical aspects, quite tempting to try if only to see how it looks in real life.

An artificial light that looks like light from the sky

http://www.coelux.com/

The Italian company CoeLux has apparently managed to create an artificial light which uses a material that mimics the atmospheric scattering, to look like sunlight and light from the sky. Judging from the photos and videos available on their website, it seems the look is very convincing.

As they point out, this could have a serious impact on architecture, as available sunlight is a factor in the design of buildings. Unfortunately, at this stage it is a prohibitively expensive product for the average consumer, and likely targeted at the construction industry. But it might be only a niche for some years before expanding to a larger scale.

The news websites PetaPixel and Colossal have previously covered this topic last month, and included some larger product photos made available by the company. But the most interesting coverage might be the one by Lux Review, who met CoeLux at an exhibition booth and made the following video. From their article:

No, the light source doesn’t move… yet. No, the colour temperature isn’t dynamic… yet. The void height needed is a metre. It consumes 340W of electrical power, but that will come down as LEDs improve.


Update: a YouTube channel presented a way to build such an artificial window at home. See: Building an artificial window.

Lighting and atmospheric effects in Reset

I’m a bit late to the party, noticing that , co-founder of Praxis, wrote a series of articles presenting an overview of the tech involved in the rendering engine he’s writing.

Shading and atmospheric effects in Praxis’ engine

The results are visually impressive, so it’s very unfortunate he doesn’t give more details. This video in particular, showcasing real-time atmospheric effects is outstanding.