WHAT ARE LED DIODES?
LED Diodes (Light Emitting Diode) are semiconducting sources of light using, invented in the beginning of 20th century, the phenomenon of electroluminescence.
Simply saying- the energy of induced atoms changes into light molecules, namely photons.
That kind of technology is called the light of the fourth generation and nowadays it constitutes the most efficient and the fastest developing light technology worldwide. The effectiveness of the light is measured in lumens per watt (lm/watt), which is the indicator saying what amount of light is generated by a certain source using 1W of power.
It is 10-12lm for bulbs, 20-30lm for halogens, and even 80-90lm for fluorescent lamps. Currently LED diodes do not exceed 120lm/W.
LED diodes can be divided into three types: THT, PLCC i POWER LED. In our ,,STARlight LED” diodes we use PLCC diodes, produced by the leading firm- OSRAM.
Each kind of diode consists of chip, meaning semiconducting component which is the main part of the diode as it generates light, and luminophore which allows the wave emitted by chip to change length and create white light. The advantage of PLCC diode is high durability, good distribution of warmth and the angle of luminosity- 120°, what is especially crucial in case of applying the general lighting.
While considering life- span of the lighting we should not take the moment when LED diode stops producing light into consideration, but the L-70 parameter. It is the time of working when diode reaches 70% of its normal brightness. When PLCC diode uses original chips and all the thermal parameters are preserved, then this time should amounts to over 60,000 hours.
It is the temperature of diode work which is important for this indicator. The temperature is influenced by the lamp construction, place where the diode is set back to housing.
What is important it’s the fact that there’s no burning phenomenon in diodes but slow degradation of light stream.
We can receive any colour we want in LED diodes, and what’s the most important this light is monochromatic, that means diodes shine with the light length we actually expect. While considering white light temperature it’s possible to generate very warm light- 2.000° K, through day light- 5.000° K to very cold one 7.000° K. The higher temperature of the colour of a particular light source is, the more similar to blue it becomes, and the less similar to red it starts to be. In “STARlight LED” we use diodes of day light- 5.000°K or 5.700°K.
Colour rendering index
Colour Rendering Index is a parameter describing how natural or how unnatural colours would the surrounding have while being illuminated by the source of light of a particular colour rendering index.
Colour rendering is defined for the lamp of a particular light colour. For measuring colour rendering we use Ra or CRI method most often.
LED diodes can be produced in various colour rendering indexes. From very low to reaching even 90%. Diodes used in “STARlight LED” has CRI >90 which is enough to illuminate places requiring technical light- for instance operating theatres.
It is the effect of blinking light- typical for fluorescent lamps as they emit light waves which have definite frequency. This sort of emission is bothersome for human’s organism and may cause eye strain as well as migraines.
Ultraviolet and infrared radiation
The process of developing LED technology is heading to eliminate the lighting which is useless as well as harmful. Properly constructed LED diode does not emit UV radiation which is unhealthy for people, especially in its shorter values.
Diodes don’t emit infrared radiation, which is sensed as warmth. Extremely opposite case is with halogens whose most energy is changed into infrared radiation and as a result it heats the surrounding.
In accordance with the act on waste electrical and electronic equipment of 2008 each company producing or launching a new electronic product on the market has to ensure its utilisation.
It also applies for LED diodes. However, they are subjected to utilization as an electronic waste not containing hazardous elements, thanks to what the whole process is far less complicated than with fluorescent lamps.
Furthermore diodes fulfil RoHS norm (Restriction of Hazardous Substances)- it’s European Union directive (2002/95/EC) of 27th January 2013 which was introduced on 1st July 2006. This directive was transported to Polish law as The Regulation of the Minister for the Economy of 27th March 2007.
The aim of ensuring the directive is to decrease the amount of dangerous substances penetrating into the environment from electronic and electric wastes.