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Chemists discover how blue light speeds blindness

phys.org

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Re: Chemists discover how blue light speeds blindness

#241

Post by bvy »

solarkraft wrote: post #176
erikbye wrote: post #166

Earlier quoted context omitted.

Both macOS and Windows 10 has on/off now, scheduling, less/more warm adjustment. Windows 10 even has sunset to sunrise based on location. EDIT: HN is becoming more like Reddit every day, I see. Ridiculous. Down-voted for pointing out the existence of helpful features. EDIT: might have been my fault.

I know these features exist in some places. But nobody had it before f.lux. And it's still - imo - one of the best implementations.

f.lux screwed up how my MBP displayed graphics so I'm just using the built-in tool now. Unfortunate.

Re: Chemists discover how blue light speeds blindness

#242

Post by copperx »

wpasc wrote: post #156
herf wrote: post #136

f.lux author here, still slogging through the article. It is hard to understand the light levels used because they use "power" (uW, mW) from a laser, and not "irradiance" (uW/cm^2 or mW/cm^2), so which area they have concentrated that light over is hard to understand. All I can see is it is from a laser, so the irradiance could be extremely high. The human lens filters most light at the peak of the given spectrum for…

Thank you for your input, but I mostly want to thank you for f.lux. It has been one of my favorite things for a long time. It's silly how long it's taken companies to provide a native blue light filter and your product just kicks ass. If you guys ever wanted to figure out your app on a smart TV (or apple TV), I know there'd be a lot of thankful people! Also, I'd love to contribute to the ongoing dev of f.lux (I don't…

I just want to remind everyone that LED backlights emit blue light that isn't eliminated by f.lux or similar utilities.

Re: Chemists discover how blue light speeds blindness

#243

Post by akashaggarwal7 »

herf wrote: post #136

f.lux author here, still slogging through the article. It is hard to understand the light levels used because they use "power" (uW, mW) from a laser, and not "irradiance" (uW/cm^2 or mW/cm^2), so which area they have concentrated that light over is hard to understand. All I can see is it is from a laser, so the irradiance could be extremely high. The human lens filters most light at the peak of the given spectrum for…

Ever since f.lux came into my life, my long screen starring hours have stopped causing me headaches and bad sleep. My phone and my computer have night mode on, all the time! Thank you for f.lux!

Re: Chemists discover how blue light speeds blindness

#244

Post by mediaman »

copperx wrote: post #242
wpasc wrote: post #156

Earlier quoted context omitted.

Thank you for your input, but I mostly want to thank you for f.lux. It has been one of my favorite things for a long time. It's silly how long it's taken companies to provide a native blue light filter and your product just kicks ass. If you guys ever wanted to figure out your app on a smart TV (or apple TV), I know there'd be a lot of thankful people! Also, I'd love to contribute to the ongoing dev of f.lux (I don't…

I just want to remind everyone that LED backlights emit blue light that isn't eliminated by f.lux or similar utilities.

Can you explain this more? If LED backlights emit multispectrum light (to get a white), and the LCD display filters those spectrum via RGB selection (say, letting less blue through, and more red/green), wouldn't this effectively filter the blue spectrum?

I know very little about this so I'm genuinely curious.

Re: Chemists discover how blue light speeds blindness

#246

Post by zengid »

herf wrote: post #136

f.lux author here, still slogging through the article. It is hard to understand the light levels used because they use "power" (uW, mW) from a laser, and not "irradiance" (uW/cm^2 or mW/cm^2), so which area they have concentrated that light over is hard to understand. All I can see is it is from a laser, so the irradiance could be extremely high. The human lens filters most light at the peak of the given spectrum for…

f.lux is amazing; thanks for your work!

Re: Chemists discover how blue light speeds blindness

#247

Post by mi100hael »

bvy wrote: post #241
solarkraft wrote: post #176

Earlier quoted context omitted.

I know these features exist in some places. But nobody had it before f.lux. And it's still - imo - one of the best implementations.

f.lux screwed up how my MBP displayed graphics so I'm just using the built-in tool now. Unfortunate.

IIRC that's a bug in the Intel graphics driver or something. I ran into that in the past as well and it's not directly f.lux's fault.

Re: Chemists discover how blue light speeds blindness

#248

Post by oh_sigh »

erikbye wrote: post #152
taneq wrote: post #150

Earlier quoted context omitted.

Hijacking this for a moment to say thanks for f.lux :) I've been running it for years and it's one of those things where you don't really notice the effect until you turn it off and then EGADS MY EYES.

Windows 10 has this built-in, so does macOS.

I would argue that it is only because of f.lux(and it popularizing the blue=bad idea) that MS/Apple/Google put this ability in their products. The technical ability to do such a thing has existed for ...decades, but no one ever did it until after f.lux came out.

Re: Chemists discover how blue light speeds blindness

#249

Post by mafuyu »

bb88 wrote: post #238
mafuyu wrote: post #110

Earlier quoted context omitted.

Sure, it's not the most exciting project, but I might do a short writeup when I'm done. I originally purchased these nice LED strip bars with enclosure in blue[0], but after reading this site by the manufacturers of a commercial green therapy light[1], I was convinced to switch to turquoise/cyan. Turquoise isn't that popular so I wasn't able to find any strips/bars, and I got these individual 3W bead LED modules inst…

So those cyan LED's have a forward voltage drop of 3.2-3.6 volts. So you'd be looking at a 32V-36V 350ma power supply or thereabouts to hook them up in series. If it were me, I'd probably run everything in parallel just to keep the voltages lower, and be able to use readily available power adapters. Aliexpress has a PWM controlled constant current driver that takes 5-35V in and outputs 350ma max [1]. 10 of them are $…

Just tested with my power supply, and the minimum V_on seems to be about 2.7V. So if I want to drive all 10 in series, I'll need 30V+. If I had three banks in a 4,3,3 configuration, I could get away with a 12V power supply as well, which would be nice since I already have a bunch of 12V 5A wall warts.

I already got the board you linked, supposedly configured for 700 mA. Haven't tested yet. The datasheet for the part says it can go up to 2A[0], so I could potentially modify the feedback circuit for 1A, which would reach the full 3W rating of the LEDs.

One issue with that driver chip is that the PWM/enable is active low, so I think I may just stick an inverter on the output of the Mesh Bee. The SDK for the NXP part has changed since the ZLL repo was updated, and I haven't had much luck getting it to compile myself.

[0]: http://www.xlsemi.com/datasheet/XL4001%20datasheet.pdf

Re: Chemists discover how blue light speeds blindness

#250

Post by mafuyu »

bb88 wrote: post #230
mafuyu wrote: post #146

Earlier quoted context omitted.

Yeah, especially with these cheapo Chinese LEDs. I looked into spectrometers, but they seem pretty pricey. Maybe some sort of plastic filter that blocks the shorter wavelengths?

How about a simple prism? That would tell you instantly if there's any blue light in the stream. Edit: You might need a mask to create a slit of light so you can see the spectrum clearly.

Oh, yeah! Totally forgot about those from high school chemistry class. :)

I'm sure there'll be _some_ blue light. I don't know if a prism would be high resolution enough to tell if it's a dangerous level.

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