Putting artificial light to service -
Conformance to the overall circadian rhythm is critical for health and well-being.
Circadian rhythm is regulated by light exposure. Typical use of the artificial light interferes with our circadian rhythm.
Blue wavelength of light suppress melatonin.
We do not yet know enough to correlate specific light parameters to specific health impacts, but we do know that natural sunlight and its dynamics throughout the day are the best for human health.
All Blue Zones and other areas with very high longevity are located in the areas with a a lot of sunlight and a stable-throughout-the-year sunlight pattern
If we spend a lot of time indoors and/or live more close to the Poles than to the equator, we can use artificial light to mimic the natural patterns of the sunlight.
https://www.versatek.com/blog/poe-lighting-circadian-rhythms/
https://www.metropolismag.com/design/circadian-lighting-survey/
Circadian rhythm is regulated by light exposure. Typical use of the artificial light interferes with our circadian rhythm.
Blue wavelength of light suppress melatonin.
We do not yet know enough to correlate specific light parameters to specific health impacts, but we do know that natural sunlight and its dynamics throughout the day are the best for human health.
All Blue Zones and other areas with very high longevity are located in the areas with a a lot of sunlight and a stable-throughout-the-year sunlight pattern
If we spend a lot of time indoors and/or live more close to the Poles than to the equator, we can use artificial light to mimic the natural patterns of the sunlight.
https://www.versatek.com/blog/poe-lighting-circadian-rhythms/
https://www.metropolismag.com/design/circadian-lighting-survey/
Parameters to know
CRI - Color Rendering Index.
It is a a quantitative, on the sale from 0 to 100, measure of the ability of the source of light to reveal the color appearance of various objects truthfully in comparison with their color appearance under natural sources of light, or sunlight. In other words, CRI defines how true-to color objects look to our eye under a specific light source.
I was unable to find scientific data on the CRI impact one the circadian rhythm and/or well-being. Based on the available information sources, it appears that CRI is more for the aesthetic appearance or design considerations. However, that we don't have scientific data does not mean it does not have an impact.
Also, the common wisdom is that eyesight worsens at an accelerated speed in people who read a lot under the artificial light. Finally, I can physically feel how my eyes are strained whether I am under the traditional light bulbs or LED light bulbs.
Balancing between the cost and cautiousness, maybe I would not buy the most expensive light bulbs with CRI of 95 and up, but I would nonetheless go for above 90.
Light Color Temperature Scale; color temperature of the full spectrum light source. Measured in Kelvins (K). The higher the Kelvins, the whiter the color temperature.
Natural sunlight throughout the day -
100-watt incandescent light bulb is about 2,800K
Wavelength of a single specific light source, such as a laser, measured in nanometers.
CRI - Color Rendering Index.
It is a a quantitative, on the sale from 0 to 100, measure of the ability of the source of light to reveal the color appearance of various objects truthfully in comparison with their color appearance under natural sources of light, or sunlight. In other words, CRI defines how true-to color objects look to our eye under a specific light source.
- 100 is the perfect color rendering, accurately produces light that matches sun and objects pear of the same color as under the sunlight;
- Most LED have CRI 80 to 90;
- CRI above 90 is considered excellent
I was unable to find scientific data on the CRI impact one the circadian rhythm and/or well-being. Based on the available information sources, it appears that CRI is more for the aesthetic appearance or design considerations. However, that we don't have scientific data does not mean it does not have an impact.
Also, the common wisdom is that eyesight worsens at an accelerated speed in people who read a lot under the artificial light. Finally, I can physically feel how my eyes are strained whether I am under the traditional light bulbs or LED light bulbs.
Balancing between the cost and cautiousness, maybe I would not buy the most expensive light bulbs with CRI of 95 and up, but I would nonetheless go for above 90.
Light Color Temperature Scale; color temperature of the full spectrum light source. Measured in Kelvins (K). The higher the Kelvins, the whiter the color temperature.
- Pitch Black Darkness is 0 K;
- Soft or Warm White is 2,000 to 3,000 K; orange to yellow-white. Most indoor light bulbs are 2,700 - 3,000 K;
- Bright White/Cool White - 3,500 - 4,100 K; more neutral
- Daylight 4,000 to 6,500; shades of day white
- The brightness of daylight around noon is 5,000 - 6,500 K
- Overcast daylight 6,500 - 8,000 K; cool white, blue tint
- 10,000 K - clear bright blue sky.
Natural sunlight throughout the day -
- Sunrise - 2,000
- An hour after dawn - 3,500
- Early morning - 4,300
- Sunlight - noon, summer, mid latitudes - 5,400
- Bright summer light - 6,400
100-watt incandescent light bulb is about 2,800K
Wavelength of a single specific light source, such as a laser, measured in nanometers.
Color Wavelength
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Wavelength of a single specific light source, such as a laser, measured in nanometers.
Visible light falls roughly between 380 and 740 nanometers (nm) and is perceived as purple through red colors. Peak wavelength - the color expressed the most and very strongly changes throughout the day. |
Color Wavelength
|
Relationship between color temperature (Kelvins) and peak wavelength in its spectrum
|
The peak wavelength is the wavelength where a spectrum reaches its highest intensity.
Wavelength in nanometers = 3,000,000 divided by Color Temperature in Kelvins. Examples -
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Understanding relationship between color temperature, measured in Kelvins and color wavelength (visible light), measured in nanometers. Image source: wikipedia "Color Temperature"
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Light brightness - lumens (used to be Watts)
A lumen is a unit of measurement of brightness of visual light, regardless of the energy consumption. More lumens = more brightness
The Watts (Wattage) measure how much electrical power a light bulb consumes. For the older, traditional, incandescent light bulbs we used to estimate the brightness of a bulb based on watts; the more the watts, the brighter the lamp. That is no longer the case especially for the newer LED etc lamp. Lumens is the best measure.
The Watts (Wattage) measure how much electrical power a light bulb consumes. For the older, traditional, incandescent light bulbs we used to estimate the brightness of a bulb based on watts; the more the watts, the brighter the lamp. That is no longer the case especially for the newer LED etc lamp. Lumens is the best measure.
INFO SOURCES
The electromagnetic spectrum, wavelength table with description -
http://www.color-theory-phenomena.nl/03.00.html
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3983044/
The electromagnetic spectrum, wavelength table with description -
http://www.color-theory-phenomena.nl/03.00.html
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3983044/
Some places where the bulbs are sold
https://verilux.com/pages/full-spectrum-light
https://www.waveformlighting.com
https://www.fullspectrumsolutions.com/collections/light-therapy-products/products/varilum-30w-color-dynamic-task-lamp-1?variant=21113749443
Daylight bulbs -
https://daylightcompany.com/us/15w-daylight-led-bulb/
Circadian floor lamp
https://www.fullspectrumsolutions.com/collections/full-spectrum-floor-lamps/products/varilum-30w-dimmable-led-floor-lamp?variant=1270852714510
Full spectrum light therapy lamp boxes (seems suitable for at home one-two person use)
https://verilux.com/collections/happylight-therapy-lamps-boxes
https://verilux.com/pages/full-spectrum-light
https://www.waveformlighting.com
https://www.fullspectrumsolutions.com/collections/light-therapy-products/products/varilum-30w-color-dynamic-task-lamp-1?variant=21113749443
Daylight bulbs -
https://daylightcompany.com/us/15w-daylight-led-bulb/
Circadian floor lamp
https://www.fullspectrumsolutions.com/collections/full-spectrum-floor-lamps/products/varilum-30w-dimmable-led-floor-lamp?variant=1270852714510
Full spectrum light therapy lamp boxes (seems suitable for at home one-two person use)
https://verilux.com/collections/happylight-therapy-lamps-boxes
More links (commercial, not science)
https://store.waveformlighting.com/products/centric-daylight-full-spectrum-flicker-free-a19-10w-led-bulb?variant=16031510659174
https://www.atlantalightbulbs.com/color-temperature-scale/
https://www.sunlightinside.com/light-and-health/natural-light-versus-artificial-light/
https://www.feit.com/products/fixtures/4500-lumen-flat-panel-light-fixture/
https://ilumi.co/collections/led-smart-lighting/products/a19-color-led-smartbulb
https://reactual.com/home-and-garden/brightest-led-light-bulb.html
https://www.seniorled.com/led-panel-lights-cct-tunable/
https://www.thelightingpractice.com/what-is-circadian-lighting/
https://www.walalight.com/the-science-of-circadian-rhythm-led-lighting/
National sleep foundation. About sleep for kids and light
https://www.sleepfoundation.org/articles/light-sleep-school-aged-children-complex-relationship
https://www.atlantalightbulbs.com/color-temperature-scale/
https://www.sunlightinside.com/light-and-health/natural-light-versus-artificial-light/
https://www.feit.com/products/fixtures/4500-lumen-flat-panel-light-fixture/
https://ilumi.co/collections/led-smart-lighting/products/a19-color-led-smartbulb
https://reactual.com/home-and-garden/brightest-led-light-bulb.html
https://www.seniorled.com/led-panel-lights-cct-tunable/
https://www.thelightingpractice.com/what-is-circadian-lighting/
https://www.walalight.com/the-science-of-circadian-rhythm-led-lighting/
National sleep foundation. About sleep for kids and light
https://www.sleepfoundation.org/articles/light-sleep-school-aged-children-complex-relationship
DUMP
Copied from Verilux Unlike ordinary indoor lighting, full spectrum light includes all colors in the electromagnetic wavelength, from infrared to ultra-violet, visible and non-visible (note that all Verilux light therapy lamps are manufactured to be UV-free).
On the light color temperature scale, pitch black darkness like at nighttime is 0 K (K = Kelvin), and daylight at around noon is around is a bright 5,000 - 5,500K. Whereas the soft, warm light bulbs in your home typically have a color temperature of just 2,700 - 3,000K.
Verilux light boxes use a full spectrum light bulb that mimics daylight at 6,500K and provide a light intensity of 10,000 lux, which is the clinical standard for effective light box therapy for treating seasonal mood disorders (see more on the specific type of light therapy that Verilux specializes in below).
These bioassays indicated blue light was slightly inferior to both sunlight and white light, but that the latter two were not significantly different.
The results suggest that metal halide white light could be a reasonable alternative to daylight PDT, which should allow a more controlled treatment that is independent of weather and yet should have similar response rates with limited pain during treatment.
Mice
https://www.ncbi.nlm.nih.gov/pubmed/29663426
Light resulted in significant improvement in mood at every interval when compared with baseline (p< .001). The 40 minute exposure resulted in a greater improvement than the 20 minute exposure (p < .001) but was not different from the 60 minute exposure (p < = .068). We conclude that immediate improvement in mood can be detected after the first session of light with exposures as short as 20 minutes, and that 40 minutes of exposure is not less effective than 60 minutes
The light used for the study was cool-white florescent delivered using a light box (Sunbox, Gaithersburg, MD) at 10,000 lux of intensity.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2913518/
Early in the day kids need exposure to longer wave light, in the blue range and up to help with the circadian rhythm and sleep patters.
https://www.sleepfoundation.org/articles/light-sleep-school-aged-children-complex-relationship
Full spectrum light therapy lamp boxes (seems suitable for at home one-two person use)
https://verilux.com/collections/happylight-therapy-lamps-boxes
Light exposure affects our health and behavior -
https://www.cell.com/trends/neurosciences/fulltext/S0166-2236(13)00197-5
Copied from Verilux Unlike ordinary indoor lighting, full spectrum light includes all colors in the electromagnetic wavelength, from infrared to ultra-violet, visible and non-visible (note that all Verilux light therapy lamps are manufactured to be UV-free).
On the light color temperature scale, pitch black darkness like at nighttime is 0 K (K = Kelvin), and daylight at around noon is around is a bright 5,000 - 5,500K. Whereas the soft, warm light bulbs in your home typically have a color temperature of just 2,700 - 3,000K.
Verilux light boxes use a full spectrum light bulb that mimics daylight at 6,500K and provide a light intensity of 10,000 lux, which is the clinical standard for effective light box therapy for treating seasonal mood disorders (see more on the specific type of light therapy that Verilux specializes in below).
These bioassays indicated blue light was slightly inferior to both sunlight and white light, but that the latter two were not significantly different.
The results suggest that metal halide white light could be a reasonable alternative to daylight PDT, which should allow a more controlled treatment that is independent of weather and yet should have similar response rates with limited pain during treatment.
Mice
https://www.ncbi.nlm.nih.gov/pubmed/29663426
Light resulted in significant improvement in mood at every interval when compared with baseline (p< .001). The 40 minute exposure resulted in a greater improvement than the 20 minute exposure (p < .001) but was not different from the 60 minute exposure (p < = .068). We conclude that immediate improvement in mood can be detected after the first session of light with exposures as short as 20 minutes, and that 40 minutes of exposure is not less effective than 60 minutes
The light used for the study was cool-white florescent delivered using a light box (Sunbox, Gaithersburg, MD) at 10,000 lux of intensity.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2913518/
Early in the day kids need exposure to longer wave light, in the blue range and up to help with the circadian rhythm and sleep patters.
https://www.sleepfoundation.org/articles/light-sleep-school-aged-children-complex-relationship
Full spectrum light therapy lamp boxes (seems suitable for at home one-two person use)
https://verilux.com/collections/happylight-therapy-lamps-boxes
Light exposure affects our health and behavior -
https://www.cell.com/trends/neurosciences/fulltext/S0166-2236(13)00197-5