Friday, November 22, 2013

A century without the Sun

 


RJUKAN, NORWAY. They have been dreaming of the Sun since 1913. A small town surrounded by mountains has finally got its portion of direct Sun. Some 400 meters above the town, a smart mirror system was installed this Autumn to cast a ray of natural light over to a town square.
 
Martin Andersen a local resident-artist has realized the Sun completely disappears from the town square by the end of September and never sheds light till the mid March. 12 years after his observation he got a German supplier of concentrated solar power to helicopter three 17-square meter mirrors on the sloop of Gaustatoppen. solar-powered computer controlled system follows the movement of the Sun and projects a fair portion of it onto Rjukan's market square.
 
A piece of art or an actual source of light? Does it matter if it makes you feel shiny?
 
P.S. we have used an instagram photo (found simply searching by the hashtag) of which we believed served best to show the reaction of  dwellers of Rjukan to the project.

Tuesday, November 12, 2013

If light is not what you expect? A slightly boring technical note

 
 
 
 
 
 
 
 
 
 
 
 

DUBAI, UAE. A question from a client has recently prompted to digg into a question why dimming LED does not feel like dimming conventional halogen spotlights. They have refurbished a restaurant and replaced spotlights with halogen lamps to LEDs. The effect did not impress: instead of warm ambience the client got pale dull environment.


The phenomenon of warmth in a dimmed halogen lamp is achieved through cooling down the tungsten filament. Less current passing through it gives out a redder spectrum of the light. Naturally we are expecting warmer hues from lesser light!


LED light source uses a different physical mechanism: electroluminescence. Halogen lamp is still incandescent in its nature. There is no major change in the color of the light when the current passes through an LED die. This change, in fact, is not discernible to the human eye. The color of light in an LED depends on the chemicals used to coat the LED die, and not on the thermal radiation.


Hope we have not yet lost you by the fourth passage. Because here is the good news:  the industry has a solution to offer. LED Engin from the USA has developed a light source which combines several dies driven separately which helps to imitate a shift from 3000K to 1800K (your incandescent lamp is 2700K, and your candle is 1700K).


Adopted from LEDs Magazine

Saturday, November 9, 2013

What if we don't need a cable to transport light?

Rendering below shows SmartLight in action. Image courtesy of source site.
 
CINCINNATI, USA. A pair of scientists from the University of Cincinnati are convinced there is enough daylight for every room in every building. Their idea is to get rid of mediums in turning light into energy and the latter into light again. Anton Hafmann and Jason Heikenfield propose to channel light through the grid of electrofluidic cells, and then 'poured' down by demand above a certain area of the room. Each cell is only a few millimeters wide and contains fluid with high optical properties. Minimal electrical stimulation (cells are self-powered by sunlight; embedded phtotvoltaics are located by the windows) turns fluid into lenses shapes, and thus controls the light. According to Heikenfeld, professor of electrical engineering, the whole system 'looks like a piece of glass that all of a sudden switches."
 
Surely, this is the system for the Gulf.
 
Full article can be found on this website.

Friday, November 8, 2013

Light music: Arcade Fire, Reflector

This morning's post on our Facebook page. We play an Arcade Fire video that gives another angle on reflectors

Excuse me, have I just drunk from a red or green cup?


Photo courtesy of source web-site











ROME, 4th Century A.C., an entertaining souvenir or a probe for royal poisons? This way or another, a Lycurgus cup remained a secret for scientist until the last decade of the 20th century. This chalice changes color: from green if lit from the front and scarlet if lit from behind. Craftsmen in Rome have grounded silver and gold till they got a nano-particle, a thousandth of a grain of a table salt!

Particles were then added to glass. Here is an explanation of Gang Logan Liu, an engineer of University of Illinois: "When hit with light, electrons belonging to the metal flecks vibrate in ways that alter the color depending on the observer’s position. When various fluids filled the cup, Liu suspected, they would change how the vibrating electrons in the glass interacted, and thus the color."

Drinks, anyone?

Full article can be found on The Smithsonian Magazine website.