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The amazing progress of LEDs

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Re: The amazing progress of LEDs

#41

Post by anonbanker »

ZoFreX wrote: post #26
patrickk wrote: post #25

Earlier quoted context omitted.

Another interesting application: growing vegetables very efficiently (potentially in urban areas). " Plants mainly need blue and red light for photosynthesis and far-red, a colour not even visible to the human eye but visible to the plant….. " This makes LEDs very interesting for this purpose - the ideal light spectrum can be achieved with LEDs. This will make more and more sense over time as the world urbanises furt…

I can think of a large market for lighting suitable for growing vegetables in your home that doesn't produce a lot of waste heat...

Some people in that market are already seeing harvests equal to 1gram per watt on LEDs. And the quality is as good as a much hotter high-pressure sodium bulb of higher wattage.

Re: The amazing progress of LEDs

#42

Post by tacoman »

webignition wrote: post #38
tacoman wrote: post #35

Earlier quoted context omitted.

What sort of plugs and connectors are you going to use for this?

Could you be a little more specific?

Sure. For example I imagine you'll have some kind of 12v receptacle in the wall where you could plug in a computer or a lamp of some kind. Is there a standard for this type of thing?

Re: The amazing progress of LEDs

#43

Post by peatmoss »

RoboTeddy wrote: post #4

One problem with current popular LED bulbs: They emit more blue light than incandescent bulbs [1]. If people light their households with LED lights at night, it might shift their circadian rhythms [2]. Screwed up circadian rhythms can have all sorts of negative health/productivity effects. [1] http://www.designingwithleds.com/measuring-light-quality-phi... [2] https://justgetflux.com/research.html

I'll be trying my hand at some LED strip / arduino programming to build a dawn alarm that goes from dim red to bright white progressively. I have a Philips halogen dawn alarm which naturally goes from orange -> red as it ramps up, but unfortunately doesn't get quite as bright as I would like for that "wake up at the cabin" experience.

I'd love to see more applications of LEDs providing the right color temperature and intensity for the time of day, as well as more applications that avoid the bulb form factor. I'd love for my ceiling to emit light like the sky...

Re: The amazing progress of LEDs

#44

Post by pc2g4d »

peatmoss wrote: post #43
RoboTeddy wrote: post #4

One problem with current popular LED bulbs: They emit more blue light than incandescent bulbs [1]. If people light their households with LED lights at night, it might shift their circadian rhythms [2]. Screwed up circadian rhythms can have all sorts of negative health/productivity effects. [1] http://www.designingwithleds.com/measuring-light-quality-phi... [2] https://justgetflux.com/research.html

I'll be trying my hand at some LED strip / arduino programming to build a dawn alarm that goes from dim red to bright white progressively. I have a Philips halogen dawn alarm which naturally goes from orange -> red as it ramps up, but unfortunately doesn't get quite as bright as I would like for that "wake up at the cabin" experience. I'd love to see more applications of LEDs providing the right color temperature and…

I'd been considering a project like this recently. I'd like some way of bringing the amount/timing/frequency of light I experience indoors closer to what I would experience were I in the outdoors, under the assumption that it would be better for my sleep/wake cycle and possibly other things.

Re: The amazing progress of LEDs

#45

Post by RoboTeddy »

peatmoss wrote: post #43
RoboTeddy wrote: post #4

One problem with current popular LED bulbs: They emit more blue light than incandescent bulbs [1]. If people light their households with LED lights at night, it might shift their circadian rhythms [2]. Screwed up circadian rhythms can have all sorts of negative health/productivity effects. [1] http://www.designingwithleds.com/measuring-light-quality-phi... [2] https://justgetflux.com/research.html

I'll be trying my hand at some LED strip / arduino programming to build a dawn alarm that goes from dim red to bright white progressively. I have a Philips halogen dawn alarm which naturally goes from orange -> red as it ramps up, but unfortunately doesn't get quite as bright as I would like for that "wake up at the cabin" experience. I'd love to see more applications of LEDs providing the right color temperature and…

The best thing I've found so far are these lights meant for growing coral:

http://www.maxspect.com/index.php?option=com_content&view=ar...

One of the models puts out UV, so be careful.

Message me (email in profile) if you want to chat!

Re: The amazing progress of LEDs

#46

Post by RoboTeddy »

jp555 wrote: post #32
RoboTeddy wrote: post #4

One problem with current popular LED bulbs: They emit more blue light than incandescent bulbs [1]. If people light their households with LED lights at night, it might shift their circadian rhythms [2]. Screwed up circadian rhythms can have all sorts of negative health/productivity effects. [1] http://www.designingwithleds.com/measuring-light-quality-phi... [2] https://justgetflux.com/research.html

Almost all the LEDs in my house are ~2700K, about the same an incandescent lights. Regarding circadian rhythm, light from near-sleep-time television watching is much more of a concern, but that's been a problem for at least 30 years.

2700K can still have a spike of blue in the wrong spot. this is a 2700K bulb: http://www.designingwithleds.com/wp-content/uploads/2014/01/...

Re: The amazing progress of LEDs

#47

Post by peatmoss »

RoboTeddy wrote: post #45
peatmoss wrote: post #43

Earlier quoted context omitted.

I'll be trying my hand at some LED strip / arduino programming to build a dawn alarm that goes from dim red to bright white progressively. I have a Philips halogen dawn alarm which naturally goes from orange -> red as it ramps up, but unfortunately doesn't get quite as bright as I would like for that "wake up at the cabin" experience. I'd love to see more applications of LEDs providing the right color temperature and…

The best thing I've found so far are these lights meant for growing coral: http://www.maxspect.com/index.php?option=com_content&view=ar... One of the models puts out UV, so be careful. Message me (email in profile) if you want to chat!

Those look like a very polished product! In my case, I'm looking to take advantage of the availability of $15 for a 300 RGB LED strip, as well as for the challenge writing my own control logic with an arduino. The SAD wake-up alarm is more of a side-benefit.

Re: The amazing progress of LEDs

#48

Post by RoboTeddy »

peatmoss wrote: post #47
RoboTeddy wrote: post #45

Earlier quoted context omitted.

The best thing I've found so far are these lights meant for growing coral: http://www.maxspect.com/index.php?option=com_content&view=ar... One of the models puts out UV, so be careful. Message me (email in profile) if you want to chat!

Those look like a very polished product! In my case, I'm looking to take advantage of the availability of $15 for a 300 RGB LED strip, as well as for the challenge writing my own control logic with an arduino. The SAD wake-up alarm is more of a side-benefit.

I don't have any SAD issues, but I find that getting proper light in the morning helps stop me from going to bed too late.

I like your project! How many watts is the LED strip?

Re: The amazing progress of LEDs

#49

Post by peatmoss »

RoboTeddy wrote: post #48
peatmoss wrote: post #47

Earlier quoted context omitted.

Those look like a very polished product! In my case, I'm looking to take advantage of the availability of $15 for a 300 RGB LED strip, as well as for the challenge writing my own control logic with an arduino. The SAD wake-up alarm is more of a side-benefit.

I don't have any SAD issues, but I find that getting proper light in the morning helps stop me from going to bed too late. I like your project! How many watts is the LED strip?

At full intensity, it draws 6a @ 12v, so 72 watts if my mental arithmetic is correct. With luck that will throw enough light to be useful.

Re: The amazing progress of LEDs

#50

Post by jp555 »

RoboTeddy wrote: post #46
jp555 wrote: post #32

Earlier quoted context omitted.

Almost all the LEDs in my house are ~2700K, about the same an incandescent lights. Regarding circadian rhythm, light from near-sleep-time television watching is much more of a concern, but that's been a problem for at least 30 years.

2700K can still have a spike of blue in the wrong spot. this is a 2700K bulb: http://www.designingwithleds.com/wp-content/uploads/2014/01/...

what is the relevance of that blue spike? Incandescent spectrum looks much more linear (http://housecraft.ca/wp-content/uploads/2012/09/spectral_res...), but appears to maybe emit more (just judging by eye) aggregate blue energy than the warm white LED.

Then again intensity towards blue-green still seems much higher in the LED, and maybe that matters more?

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