Beam angle - Indicates how broadly the light is emitted from a reflector lamp. It can be thought of as an imaginary cone whose apex intersects the lamp face, and the breadth of the cone extends outwards to the point where luminous intensity has diminished to 50% of the centre beam value.
Binning - LEDs are manufactured in sheets. The finest property LEDs are found in the center of the sheet. The farther you proceed from the center the more problematic are the LEDs to maintain consistency for color (K) and for brightness. A process of sorting out individual LEDs according to their color, photmetric and electrical parameters. Raw LEDs cannot yet be manufactured with the same consistency as conventional light sources, and the color differences from one LED to the next can be visible to the naked eye. This situation is handled by measuring 100% of the production and all LEDs having similar values are placed in the same bin.
Candela (cd) - The unit of measurement for luminous intensity, which refers to the quantity of light emitted in a particular direction. The symbol is cd.
CCTCorrelated Color Temperature (CCT) - An approximate indication of the color impression created by a white light source. It basically describes how ‘warm’ or ‘cool’ the appearance of the light will be. The unit of measurement is the Kelvin (K). Sylvania LED lamps are offered in color temperatures of 2500-2700K (extra warm, similar to incandescent), 3000K (warm white, similar to halogen), 4000K (neutral white) and 6000K (daylight).
Color Rendering Index (CRI) - Indicates the ability of a light source to illuminate objects in their true colours. It is measured by shining the light of the lamp onto fifteen test colours (R1 to R15) and measuring the shift from the true colour to the apparent colour under the test lamp. The scores of the individual results are averaged to derive the Ra value. The higher the Ra the better the colour rendering properties. Daylight and incandescent lamps are the only sources to achieve perfect score of Ra 100. All Sylvania LEDs have a good Ra >80, and certain premium versions achieve Ra >90.
Dimmability - Most conventional dimmers have been designed for incandescent lamps and are therefore rated for higher minimum loads (W) than LED lamps consume. There may therefore be some restrictions in terms of functionality of dimmers with individual LEDs – but when more than one lamp is used to increase the total loading, dimming becomes easier.
Drivers - Electronic devices that transform the high mains voltage into a constant current lower voltage for operating the LEDs. A miniature electronic driver is contained inside the base of each Sylvania LED lamp.
Efficacy - Measurement of Total Lamp Lumens divided by Total Lamp Wattage. The higher the better.
Heat Sink - A device used to conduct heat away from the LED sources and dissipate it to the surrounding air. The more efficiently an LED is cooled the greater its efficacy, light output and lifetime. Materials having excellent thermal properties and optimised cooling fin gemoetries are engineered into Sylvania lamps to deliver
Infrared (IR) Radiation - Comprises electromagnetic waves in the spectral range between visible light and microwaves, which produce a heating effect when absorbed by materials. All lamps produce infrared radiation, but the quantity emitted by LEDs is far lower than other technologies and this makes them ideal for reducing air conditioning load, as well as for the illumination of heat-sensitive goods.
LED (Light Emitting Diode) - An electronic semiconductor component which emits light when an electrical current flows through it. The colour of light emitted depends on the chemical doping of the semiconductor material.
LEED (Leadership in Energy and Environmental Design) - A program of total enterprise energy and environmental efficiency developed by U.S. Green Building Council. Energy efficient lighting is one component of a LEED rated facility.
Lens - An optical component having two refractive surfaces, at least one of which is either convex or concave. In LED lamps the function of a lens is to focus or disperse the light rays to achieve the desired beam angle or light distribution pattern.
Lifetime - LED lamps can have extremely long lives, however their light output diminshes as they age. They can carry on working until they are emitting less than 10% of their initial light output, but with so little light left they would be practically useless. SYLVANIA defines the lifetime of its LED lamps the same way as for other lamps: i.e. the burning hours until the light output has decreased to 70% of the initial value, or when 50% of a group of lamps will have failed – whichever is the soonest. The International Electrotechnical Commission (IEC) is currently preparing an international standard based on similar threshold values.
LM-79/LM-80 - Protocols establiushed by DOE to test the performance of LED lumnaires. LM-79 protocols test for compliance to claims of Light Distribution, Lumens, Color and Spatial Non-Uniformity. LM-80 protocols test for compliance to claims of Usable Lifetime. Many electrical utilities request compliance with LM-79/80 for rebate consideration.
Lumen - The photometric unit of luminous flux. Luminous flux is a measure of the total quantity of visible radiation emitted in all directions, which is weighted to take account of the sensitivity of the human eye to different colors.
Phosphors - Chemical coatings applied over LEDs to give the emitted light a particular color.
Reflector - An optical component having a mirror surface, which captures light rays from the source and bounces them back at a particular angle. Although more commonly used in incandescent and halogen lamps, some Sylvania LED lamps use reflectors to control their light instead of a lens.
SSL (Solid Sate Lighting) - type of lighting that uses semiconductor light-emitting diodes (LEDs), organic light-emitting diodes (OLED), or polymer light-emitting diodes (PLED) as sources of illumination rather than electrical filaments, plasma (used in arc lamps such as fluorescent lamps), or gas.
Switching Frequency - LED lamps cannot be switched on and off indefinitely, but are rated to tolerate an impressive 60,000 switching cycles or more.
TCO (Total Cost of Ownership) - TCO includes all the costs over the entire life of a lamp or for a particular operating time. It covers procurement costs, electricity consumption costs, relamping costs and may even incorporate a reduction in the necessary air conditioning load. LEDs are presently more expensive to purchase than lamps based on other technologies, but their minimal energy consumption results in rapid payback when replacing incandescent and halogen lamps.
Transformer - A device for reducing the high mains voltage down to a lower voltage, particularly common for the operation of 12 Volt halogen lamps. A distinction is made between conventional (magnetic) transformers and electronic transformers. Sylvania low voltage LEDs will function on all magnetic transformers, and compatibility details with electronic transformers are available in the technical data sheets.
Ultra Violet (UV) Radiation - Comprises electromagnetic waves in the spectral range between visible light and X-rays, which are invisible to the human eye but essential for all life (delivered via natural sunlight). Small amounts of UV are emitted by many light sources (eg Halogen and Discharge) and over time will cause fading of coloured objects being illuminated. Sylvania LED lamps do not emit any UV radiation.
Volt- The derived SI unit of electrical pressure (symbol V). Lowvoltage LED lamps (12 V) operate with transformers. High-voltage LED lamps can be operated directly on the mains supply (220-240V).
Watt - is the SI unit of power and was used for incandescent lamps as an indication of their light output. Since modern energysaving lamps and LED lamps consume far less power to achieve the same brightness, however, the wattage is no longer as meaningful. The lumen value is now used instead.