LED Lighting Technology Glossary

LED Lighting Inc. puts forth a continual effort to provide the most well-rounded, educated and helpful information for you to make the best LED lighting decisions. We are sure to provide you with all the information you need to make cost-effective, creative and efficient LED Lighting designs.

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We have compiled some of the most commonly used terms in the LED lighting industry and their definitions to help you fully understand the language and what you are purchasing. If you have any further questions about what anything means, or the specifications of any product, don’t hesitate to contact LED Lighting Inc. and we will be happy to help you! LED Lighting Inc., the Future of Lighting.

Contact LED Lighting Inc. for creative, energy-efficient LED Lighting solutions. LED Lighting Inc., the future of lighting.

Ambient Temperature (Ta)

Air temperature surrounding the device

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Ampere (Amp)

Unit of measurement for the rate of flow of electrical current.

Current (Amps) = Power (Watts) / Voltage (Volts)

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Color Rendering

General expression referring to the effect of a light source on the color appearance of objects.

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Color Rendering Index (CRI)

Measurement of the degree of color shift objects undergo when illuminated by the light source. This is compared with those same objects when illuminated by a reference source of comparable color temperature. The reference source typically has a CRI of 100.

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Object possessing irregularities on the surface causing a scattered reflection.

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Digital Addressable Lighting Interface (DALI)

Digital Communications Protocol for controlling and dimming lighting fixtures. This was originally developed in Europe.

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Electronics used to power the illumination sources.

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Light output of a light source (lumens) divided by total electrical power input to the source (Watt). Lumens per Watt. (lm/W)

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Measurement of the intensity of light falling on a surface area.

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Illuminating Engineering Society of North America (IES)

Recognized technical authority of illumination. The IES communicates information on all aspects of good lighting practices.

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Junction Temperature (Tj)

Temperature of the LED’s active region.

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Light Emitting Diode (LED)

A solid-state semiconductor device converting electrical energy directly into light.

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International (SI) unit of luminous flux or the quantity of light equaling the amount of light spread over a square foot of surface by one candle power when all parts of the surface are exactly 12” from the light source.

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Luminous Flux

Measurement of perceived power of light, adjusted to reflect varying sensitivity of the human eye to different wavelengths of light.

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Lux (lx)

International (SI) unit of Illuminance.

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Radiant Flux

Total energy emitted by a light source across all wavelengths. This is measured in Watts.

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