Part One of the Exploration and Discovery of LEDs
You probably are not familiar with SORAA. SORAA (which means “sky” in kanji) was founded in 2008 by professor Shuji Nakamura, Nobel Laureate in Physics, professor Steven DenBarres, Co-Director of the Solid State Lighting & Energy Electronics Center, and Jim Speck, professor of Light and Energy, at UCSB. Professor Nakamura holds the patent on GaN-on-GaN on Sapphire (Gallium Nitride) LED (light-emitting diodes) technology. These crystals are up to a thousand times purer than any other LED crystal.
Professors Isamu Akasaki and Hiroshi Amano of Nagoya University, Japan, (who also received Nobel prizes along with Nakamura) developed their first high-quality gallium nitride crystal in 1986 by growing high quality GaN on top of a layer of aluminium nitride on the Sapphire substrate. Nakamura refined the method by experimenting with both high and low temperatures. Another technology DenBaars has been working on is ammono-thermal which uses heat, mass, and crystal growth of GaN in the ammonothermal process for bulk gallium nitride crystals.
GaN on GaN has paved the way for what is now white lights (a mixture of red, blue, and green LEDs). They’re creating white light with violet phosphor while removing blue, thus creating pleasing white light.
They are also using different planes to create semi-polar LEDs. This is quite extraordinary because this is a major advancement in the sterilization techniques used for surgery. DenBaars and Shuji Nakamura have been working overtime. Their ZEROBLUE technology gave way to the invention of Soraa ZERO. It uses blue, green, and red phosphors, which produces a spectrum with a wide gap in the blue range. This light, the world’s first completely blue-free LED lamp portfolio, is named Soraa HEALTHY.
ZEROBLUE :: Soraa
Meet Soraa HEALTHY™, the world's first and only blue-free LED lamp that creates light environments that support health…
We know the sun emits blue light in the morning and this affects our day. We are also aware that alot of us, either from work, bad weather, school, or by choice, are indoors under artificial light and that affects our ability to go to sleep. When it’s time for rest we end up with insomnia. This light source helps with our circadian health, especially for hospital staff and patients.
Soraa HEALTHY products feature the patented ZEROBLUE technology. It emits a blue-free spectrum, reducing melanopic lumens by ~40 percent compared to conventional LEDs — and without suffering from the yellow cast of other sleep-friendly LEDs. We thrive on natural aka sunlight and need it to survive.
Greg Yeutter’s Medium publication, Simple Bulb, sells 3 separate blue light bulbs. He is involved in Human-Centric Lighting which many companies are are advocates such as Glamox. Light affects our mood, health, mental well-being and it’s vitally important to understand the biological effects it has on all of us. Simple Bulb’s “Bedtime” Bulb (LessBlue™ Technology) is one example. See the image below —
Another technology, Aurora™, has emerged with “Lumiram BLU/ENERGYLITE™ Light Therapy“ in which you control the amount of brightness. It is used for the treatment of Seasonal Affective disorder (SAD), mood swings, etc. This 60 x single peak wavelength 470–475 nm.
Color rendering is measured by TM-30 Rf, and white rendering by Soraa’s internally-developed whiteness rendering index Rw. Whiteness in natural light is provided by ultra-violet radiation and we know this is harmful so it’s replaced with the violet light. Soraa VIVID takes both, Rf and Rw, and gives you a saturated richer color.
The Illuminating Engineering Society (IES) has been around since 1906. They publish two trade publications, “ Lighting Design + Application” (LD+A) and “LEUKOS,” the Journal of the Illuminating Engineering Society. LD+A is a popular, award-winning, application-oriented monthly magazine featuring innovative designs and best practices.
Designers love Radiant because the white light is his nmay only include one sense (seeing) but the ambience, lighting and music spur smiles and emotions. It’s an integral part in transforming how a person reacts to light. SORAA is the master of it. Click on “Learn” then “Beautiful” under their menu. The Crosswater Showroom in Dartford, England is an example or The Spice Room, a restaurant in Sydney, Australia another. The impact of how light dictates your mood? Phenomenal.
Light has influenced us in theatre, watching a musical artist in a huge venue, etc. but it can have negative effects. We need light to see in order to drive cars at night for instance.
Shuji Nakamura and funded by Khosla Ventures and NEA, calls the lighting product “helia.” It’s a light bulb and smart controller set that dynamically adjusts lighting to help households sleep better, achieve a more convenient lifestyle, and light a house more efficiently.
The light bulbs come in the form of a widely used down light (BR30) and can be screwed into standard sockets at a home or business. To make the lights smart, you need to buy one of the controllers, which pops into the center of one of the lights and contains sensors and a communication chip to enable the lights to connect information over the power line.
One last topic is about ambient or natural light. SORAA has executed this well and the most important discovery for all of us who wear glasses, concerns blue-free light.
- Blue light is a color in the visible light spectrum between 400nm and 500nm; making it one of the shortest, highest-energy wavelengths that can be seen by human eyes. Blue light is a short wavelength, which means it produces higher amounts of energy. How does blue light impact you? Studies show that exposure to blue light can cause eyestrain, fatigue, headaches, and sleeplessness. Blue Light in the visible light spectrum.(*from BlueTech Lenses)
The order of colors in light, arranged from shortest wavelength to longest, is called the visible spectrum of light. The image below shows light’s visible spectrum, which runs from violet to red. You might recognize the spectrum as the order of colors in a rainbow.
But light waves can also have wavelengths lower or higher than the wavelengths in the visible spectrum, and many familiar types of radiation are just light waves with other wavelengths. Ultraviolet light and x-rays have wavelengths shorter than violet light, and infrared (heat) and radio waves have wavelengths longer than red light.
The full range of wavelengths for light is called the “electromagnetic spectrum.” The image and table below show which wavelength ranges in the electromagnetic spectrum correspond to which types of light.
Wavelength of White Light : The white light extends from the 400 nm to 750 nm. The white colour when passed through the prism it gets diffracted into all the other colours.
Wavelength of Ultraviolet Light : Ultraviolet light belongs to electromagnetic spectrum and it extends from end of visible region and x-rays. Ultraviolet light is in the range of 10 nm to 400 nm with energies from 3eV to 124 eV. Ultraviolet light gets its name because it is the light closest to the violet portion of visible light.
Wavelength of Red Light : The red light of the visible spectrum has a wavelength of about 650 nm. The best place to see natural red colour is at sunrise and sunset when red or orange colours are present. This is because at the sunrise and sunset the wavelengths associated with red and orange colours are not properly scattered by the atmosphere than the wavelength of other colours (like blue and purple).
Wavelength of Yellow Light : The yellow light has a wavelength of about 570 nm. Low-pressure sodium lamps, like those used in parking lots, emit a yellow (wavelength 589 nm) light.
Wavelength of Green Light : The green light has a wavelength of about 510 nm. Grass appears green because all of the colours in the visible part of the spectrum are absorbed by the grass except green. The grass reflects green wavelength, therefore the grass appears green.
Wavelength of Blue Light : The blue light which we see has a wavelength of about 475 nm. The atmosphere scatter shorter wavelength efficiently and hence the wavelength associated with blue colour is scattered more efficiently by the atmosphere. This is the reason why we see sky to be blue.
Wavelength of Violet Light : The violet light has a wavelength of about 400 nm. As already discussed the violet and blue which belongs to short wavelength region are more efficiently scattered than other wavelengths. Our eyes are more sensitive to the blue colour and hence we see sky blue and not violet.
Wavelength of Indigo Light : The indigo lies between the blue color and the violet color and hence the wavelength of indigo lies between 420 nm to 450 nm.
Wavelength of Infrared Light : Infrared (IR) radiation belongs to electromagnetic radiation spectrum. Infrared has a longer wavelength than visible light. Infrared is close to red colour in visible spectrum and hence it is sort of “redder-than-red” light or “beyond red” light, that is why the name infrared. Infrared radiation cannot be seen but can only be feel as a heat. The best example of feeling the infrared by yourself is feeling the heat after the burner is turned off.
For more info visit : https://www.electrikals.com/