Viewing profile — hakonjdjohnsen

Agreed, that was a really good talk! It is kind of scary how simple some of these exploits that find their way into smartwatched for children are

This video by AlphaPhoenix is absolutely incredible! I do research in (nonimaging) optics and I am used to thinking about the propagation of light. Still, there is something amazin…

Thermophotovoltaics is really cool. It is an old idea but recently several groups (including the group behind fourth power) have shown much better experimental performance than bef…

I think there is at least some plausible interpretation of this that points to more than marketing fluff. You want to count particles per volume of air, so conventional sensors use…

Yeah good point! When I came across this amazing project and wanted to share it to HN, I was debating whether to post the youtube link or the project page. I decided to post the pr…

See also the youtube video about the project: https://youtu.be/8s9TjRz01fo

https://www.youtube.com/watch?v=8s9TjRz01fo

I found this presentation from the Disobey 2025 conference to be a really good and entertaining watch! Last year the presenter also wrote a blog post about the attack, which receiv…

Cool concept! I do research in solar concentrator optics, so I enjoy seeing such completely different applications of concentrated sunlight. Still, I am not fully convinced in this…

The reason we get a lot of light from the sun is not that the sun is particularily "bright" (high radiance) compared to other stars, it is because the the sun has an absolutely hug…

> You make a big ring (roughly of the same area of the spot you are trying to make on the ground) Unfortunately, this is not how the size of the spot on the ground is decided. Sunl…

So the birdkill is actually from a separate focal spot near the absorber where standby heliostats are focused? Interesting, I did not know that! Makes me wonder why standby heliost…

Looks really cool! I look forward to reading your paper. Do you know if a recording of the talk is/will be posted somewhere?

Interesting! I added an email address to my profile now

Yes, exactly. I have not looked at Mitsuba 2, but Mitsuba 3 is absolutely along these lines. It is just starting to be picked up by some of the nonimaging/illumination community, e…

This, very much this! I do research in a subfield of optics called nonimaging optics (optics for energy transfer, e.g. solar concentrators or lighting systems). We typically use th…

Hi, I help run an academic conference on Nonimaging Optics (optics for optimal energy transfer in solar concentrators or illumination systems). This year, we are hosting a design c…

There are also two systems in Sydney, the big tall one on Rhodes Central [1] and the slightly smaller on One Central Park [2]. I think the idea is that by removing some of the shad…