Cree leds are no thermal radiators. Cree leds are no thermal radiators. In other words, they emit no electromagnetic radiation, which is sometimes also called temperature radiation. The light that radiate cree leds is almost completely monochrome. With monochrome is meant that moves the emitted light only in a limited spectrum.
For this reason used mostly cree leds as light, because they are more effective in this field than other lamps, such as for example incandescent lamps. Light bulbs are namely thermal radiators. Lamps you must filter out namely once a large part of the spectrum by means of colour filters to create a monochrome effect. Check with cancer research to learn more. This operation is not necessary with cree leds and this makes them suitable for use as a signal light. It was not possible cree leds for all colors of the spectrum which is visible to the human eye, to make long time. So cree leds cannot be inserted for example always still to use traffic lights. It is is unfortunately not possible to build cree leds, which had a blue-green colour.
But now there’s cree leds, which emit a blue light for several years and they enjoy increasing popularity. You can also use this blue cree leds to produce white light. Cree leds are used for this purpose luminescent against the blue, which change the colour of the light. As a result, that this cree leds then have a wide spectral range due to the built-in fluorescent and at the same time a small amount of blue light. The characteristic curve for current and voltage is exceptionally increasing cree LEDs, and among other things depends on the temperature. The luminous flux, which passing through them is almost proportional to the operating current. The voltage depends on the temperature. When the temperature rises, the voltage decreases as it actually is the case for all semiconductor diodes.