LED Terminology

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What does that mean?  To help you understand our product we put together a list of some terms that you may come across in the world of LED technology.

LED LED or "Light Emitting Diode" is a semi-conductor made of a combination of substrates to emit light when charged with a low DC current, typically at 20 milli amp (mA). This drive current spec is important, because "driving" the LED above 20mA to achieve a greater brightness shortens the life of the LED dramatically.
LED Life LED life is typically rated for 100,000 hours by most LED suppliers. In outdoor applications its "actual life" greatly depends on the design of the overall system, type of substrate materials, LED grade, drive current, and manufacturing technology used by the display manufacturer.
Candela (cd) Candela is a unit of brightness used specifically for LED's. The measurement is made at the 0 axis. Its rating varies with the half-intensity viewing angle of LED. The unit of milli candela is also used interchangeably, for which 1 cd = 1,000 mcd.
Half Intensity Angle Half Intensity refers to the viewing angle rating as specified by the LED manufacturer, such as Hewlett Packard or Nichia. This simply states that at X degrees the LED intensity will be as intense as it would be at 0 degrees. Our high-brightness & high-contrast design allows the actual visible angle to be much larger than the intensity angle.
Max. Viewing Angle The maximum viewing angle as specified by various sign manufacturers could be quite misleading. This measurement is ambiguous and varies greatly with ambient light conditions. To truly compare signs of different manufacturers, one should use the intensity angle.
Constant Current Constant current design and constant voltage design refer to the way LED’s are "driven". To ensure consistent LED brightness, constant current design is used by us. This technology is more expensive, but produces a high quality display. Constant voltage design allows the LED’s to exceed their 20mA current rating, thereby shortening the life of the display and producing non-uniform color.
NIT NIT is a measurement of brightness used to rate LED displays. NIT is expressed in "candela per square meter". While NIT is the measurement of brightness being emitted from the LED display, be aware that contrast plays a key role in determining the legibility of an LED display.
Contrast The contrast between the LED’s and their surroundings can influence the legibility of the display. Our supplier has addressed this issue by developing a proprietary, patented design that eliminates the glare and thereby provides the best legibility for the display.
Pixel A pixel is a single point of light, capable of producing all of the colors of the display. This differs from incandescent displays that produce a single color per lamp, which is not a true pixel.
Full Matrix A full matrix display allows the user to combine the entire display’s pixels to produce larger characters and graphics. This feature, as offered by us, allows greater flexibility and creativity.
UL Underwriters Laboratory certification is a critical factor for installation in most US cities. Our outdoor displays are all certified by UL. Our suppliers product quality is further guaranteed with a prestigious ISO9000 compliant certificate.

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