131–140 of 243 posts
Earlier quoted context omitted.
Hmm, never heard that before, I’ll have to research it more. Maybe the UV from sunlight is killing something you are allergic to. We don’t have UV for safety and energy efficiency reasons but you could try buying some strong UV lamps and see if that helps. Ideally you turn them on when you are out of the room so they don’t damage your eyes or cause cancer.
Oh, thanks. I will explore more on this.
I saw "artificial sunlight" and thought "oh wow I'd love to see the spectrogram of the lighting solution this person came up with". I was disappointed to merely see "CRI 95+". https://www.youtube.com/watch?v=lH_owRxupC0 This is great video on the shortcomings of "CRI" - it explains in detail CRI, CRI extended, TLCI, TM-30, and SSI. Brightness and color temperature are only two small parts of lighting - more people sh…
I cannot remember if I first saw this here on HN but, here is a detailed video of an incredible artificial sunlight rig build. It's big but the results look, well, amazingly real, at least to the camera. https://www.youtube.com/watch?v=6bqBsHSwPgw
Years ago, I remember seeing that a firm was using fiber optic bundles to bring sunlight in from the roof into the inner spaces of an office building. Does anyone know anything about that?
I've been tracking that on and off for years - https://parans.com/ Not sure it's really caught on, but it's out there
I wonder what the light's spectra and intensity are.
I'm guessing that its cost is prohibitive, or maybe the light's characteristics are just not so great.
I'd love to be able to do some low-intensity tanning at home, for vitamin D and skin health.
Thanks a ton.
The brightness enhancement film is a transparent optical film. It consists of a three-layer structure. The bottom layer of the light-incident surface needs to provide a certain degree of haze by back coating, the middle layer is a transparent PET substrate layer, and the upper layer of light-emitting cotton. It is a microprism structure. When the microprism layer passes through the fine prism structure of the surface layer, the light intensity distribution is controlled by refraction, total reflection, light accumulation, etc., and the light scattered by the light source is concentrated toward the front side, and the unused light outside the viewing angle passes through the light.
So, it's similar to your design, but the grooves are very small.
DIY Perks also attempted to make artificial sunlight at home, also focusing on things like Rayleigh scattering! This was a great watch: https://www.youtube.com/watch?v=6bqBsHSwPgw EDIT: After reading the article, I see the OP calls out DIY Perks specifically - the OPs design is much more compact :) > It's compact. The total size is 19cm x 19cm x 9cm. This is quite compact for a 5cm focal length and an effective light…
It uses a trash can plus a super-bright LED bulb plus a plastic book magnifier.
The main trick is that you can get a big magazine-sized flat plastic fresnel lens for like 10 bucks.
The original poster's solution is definitely better, but it's also possible to do this on the cheap with no 3D printing (or in fact, any skills whatsoever).
For me, the problem with this setup (and with most high efficiency LED lights) is the lack of red wavelenghts. Real sunlight has a substantial amount of energy in the very red end of the visible spectrum (700 nm) and also of course quite a bit in the infrared. These lamps have two spectral peaks: a narrow peak in the blue range, around 450 nm, a broader peak in the green, centered around 580 nm. That greenish peak fa…
Earlier quoted context omitted.
Are you guys looking at fabbing your own LED dies? The actual spectrum of commercial LEDs is all over the place when you start measuring it it with a spectrometer, even when they supposedly have a high CRI. Especially if you want some temperature that isn't 6500K. It was so bad that when I was building a night light for my eink desktop I ended up using halogen bulbs which I could undervolt. The main issue was that I…
there are companies that can do custom phosphor formulations for you to target a specific output. The minimum order quantities don’t make it practical for DIY but not too bad for a small startup. Our approach is to mix a bunch of different LEDs together to get the color and spectrum we want. Check out telelumen.com for an example that uses 16 chips. These are designed for researchers
Looking at the spectrum graphs for your lights I'm seeing the telltale phosphor coating spike for both warm and cool white leds. An understandable tradeoff, but with the brightness of monochromatic LEDs you can get today one that's not essential any more.
With the drop in costs for both controllers and pcbs since then you should be able to get telelumen quality temperature spectra without the matching price, especially if you can get LEDs that have consistent spectra for their nominal wavelength - you only need to tune the controller once instead of for each light.
Earlier quoted context omitted.
Yes, it’s region specific. In the USA sales generally go through a partner. But it is a fraction of the weight, depth, and cost of the large coelux units that run $40k plus install. We also realized there is a need for producing just the sky with great photo metrics and that is even thinner and less expensive. A lot of interesting reading can be found in our interactive spec sheet here: https://www.innerscene.com/pro…
Is your pricing also a fraction of coelux's, or just the dimensions? :o)
Emphasis mine. I think this was already answered :)
Earlier quoted context omitted.
It’s infuriating that you only have “accept all cookies” and no other options. Oh but I do absolutely love this concept. I’m curious if you’ve had lots of interest from these billionaires building bunkers, if that story is even true!
Not a bunker per say but I recently learned that in some states/cities you don’t pay property taxes on square footage below ground so you end up with people building more space below than above ground and Virtual Sun can make it feel like above ground space. Just visited a billionaire project last week where this was the case.
Still, I'll keep this in mind on the off chance it ever becomes relevant to me.