LED Lighting Definitions & Education

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Accent lighting: Draws attention to special features or enhances the aesthetic qualities of an indoor or outdoor environment.

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Ambient: The surrounding light level in a given area. It is also the temperature in which a LED light source is expected to operate in. Referring to light, it is the light given off by the Sun, Moon, other light fixtures nearby or even within the same space.

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Ambient lighting: Provides general illumination indoors for daily activities, and outdoors for safety and security.

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Amperage: The strength of an electrical current measured in amperes. The higher the amperage number, the higher the ability to place more devices on a circuit that will be driven by that amperage.

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Bulb: It is not a LED. A LED light bulb is a finished product that has the LEDs installed, electrical components installed and is ready to be used by the consumer. A LED light bulb is screwed in place, twisted and locked in place, pressed into sockets or contact terminals.

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Chromaticity: Chromaticity tells you what the lamp itself or a neutral surface illuminated by a lamp will look like. Chromaticity sets the "tone" or atmosphere of a room: warm, cool or something in between. Chromaticity (sometimes called color temperature) is usually measured in Kelvins. It can also be defined by using x and y coordinated against a standard chromaticity scale developed by the Commission Internationale de l'Éclairage (CIE).

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Color Rendering Index (CRI): Also CCT or Correlated Color Temperature. It is a measure of the quality of light. A measurement of the amount of color shift that objects undergo when lighted by a light source as compared with the color of those same objects when seen under a reference light source of comparable color temperature. LED light CRI values generally range from 60(average) to 90(best). High CRI equates to sharper, crisper, more natural colored pictures while at the same time reducing glare.

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Color Temperature: A measure of the color of a light source relative to a black body at a particular temperature expressed in degrees Kelvin (K). Incandescent lights have a low color temperature (approximately 2800K) and have a red-yellowish tone; daylight has a high color temperature (approximately 6000K) and appears bluish (the most popular fluorescent light, Cool White, ia rated at 4100K). Lamps with color temperatures below 5000K tend to be more yellow/red, lamps rated between 5000 and 6000K are viewed as white, while lamps above 6000K tend to have a blue cast.

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Daylighting: The practice of placing windows or other openings and reflective surfaces so that during the day natural light provides effective internal lighting. Particular attention is given to daylighting while designing a building when the aim is to maximize visual comfort or to reduce energy use. Energy savings can be achieved either from the reduced use of artificial lighting or from passive solar heating or cooling.

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Dimmer: The use of dimmers and dimmer devices will reduces the wattage and output of lighting, which helps save energy.

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Efficacy:The ratio of light produced to energy consumed. It's measured as the number of lumens produced divided by the rate of electricity consumption (lumens per watt).

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Foot-Candle (FC): The unit is defined as the amount of illumination the inside surface of an imaginary 1-foot radius sphere would be receiving if there were a uniform point source of one candela in the exact center of the sphere. Basically, the amount of light that a single candle would provide to a 1ft. radius sphere.

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Full Spectrum: A light bulb or lamp that produces a light spectrum that covers the entire range of visible light (400-700nm) without gaps in its spectral output. White LEDs are inherently a full spectrum light source.

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Glare: The excessive brightness from a direct light source that makes it difficult to see what one wishes to see. A bright object in front of a dark background usually will cause glare. Bright lights reflecting off a television or computer screen or even a printed page produces glare. Intense light sources—such as bright incandescent lamps—are likely to produce more direct glare than large fluorescent lamps. However, glare is primarily the result of relative placement of light sources and the objects being viewed.

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Intensity: Is a measure of the time-averaged energy flux or amount of light striking a given area. For bulbs alone this is measured in terms of lumens while for lighting fixtures it is measured in lux (lumens/sq. meter).

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Kelvin Color Temperature: A measure of the color of a light source relative to a black body at a particular temperature expressed in degrees Kelvin (K). Incandescent lights have a low color temperature (approximately 2800K) and have a red-yellowish tone; daylight has a high color temperature (approximately 6000K) and appears bluish (the most popular fluorescent light, Cool White, is rated at 4100K). Today, the phosphors used in fluorescent lamps can be blended to provide any desired color temperature in the range from 2800K to 6000K. Lamps with color temperatures below 5000K tend to be more yellow/red, lamps rated between 5000 and 6000K are viewed as white, while lamps above 6000K tend to have a blue cast.

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Light Emitting Diode (LED): LED means light emitting diode. LEDs are a solid state device and do not require heating of a filament to create light. Rather, electricity is passed through a chemical compound that is excited and that generates light.

LEDs are not bulbs or lamps in the true sense of the word and application. LEDs require a lot of work to make them ready to be used by the consumer. They need to be placed on a circuit board or other material that will allow electricity to pass through it at a specific voltage and current, and with components required to operate them at specific voltages such as 12vdc, 24vdc or 120vac. They do not come ready to plug into a 12volt or 120 volt power source.

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LED Bar: Refers to a solid strip of material on which LEDs have been soldered to, along with resistors and other components that a specific product requires to make them operate at the stated operating voltage. The Bars are usually an enclosed strip of LEDs. Enclosures are plastics, or aluminum, or metal composites with various types of lens/cover plates.

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LED Cluster or Array: A group of LEDs set in a square, rectangular or linear pattern, and formatted to be operated at a specific voltage. They will always include two wires called leads. One is positive, the other negative.

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LED Drivers: are current control devices that replace the need for resistors. LED Drivers respond to the changing input voltage while maintaining a constant amount of current (output power) to the LED as its electrical properties change with temperature.

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LED Lighting: A general term used by those who do not know the specific type or category of LED lighting they are after. LED lighting includes LED bulbs and fixtures, flashlights, strips, clusters and other LED light sources.

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LED Strip: LED Strips are usually printed circuit boards with LEDs soldered to the board. The strip can be rigid, or flexible and without any enclosure to protect the LED and circuit.

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Low Voltage: With LEDs, that means 12vDC 24vDC or 48vDC, as opposed to 110/120vac which is high voltage. With LEDs, low voltage is commonly 12vdc sometimes at 24vdc. To run these low voltage lights, power will have to be sent to the light through a power supply/transformer/adapter that is hooked up to 110/120/240vac power lines. The actual voltage reaching the light will be at 12vdc.

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Lumen Maintenance: How well a LED light bulb is able to retain its intensity when compared to new. Typically a high power smd LED bulb will retain 70% of its intensity for 40,000-50,000 hours. That means a good quality LED bulb will run 8 hours a day for 13 years at 70% of its new condition. No other light source can do this.

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Lumens: The unit of luminous flux in the International System, equal to the amount of light given out through a solid angle by a source of one candela intensity radiating equally in all directions. Used to measure light bulbs as stand alone light sources. Lighting fixtures are measured by lux output which is lumens per square meter. See for a better understanding - Lumens Illuminance

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Lux: Typically used to measure the light intensity produced by a lighting fixture. The higher the lux reading the more light the lighting fixture is producing over a given area. Known as lumens per square meter.

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mA: stands for milliamp. 1000mA equals 1.0 amp. All LEDs run on current and current is measured in milliamps. All LED products have a mA rating at which they are to be powered at.

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Max Rated Temperature:, or Operating Temperature is the ambient temperature where the LED light source is installed at and should be maintained at. In most case that is around 40-50° Celsius. That is comparable to 104° F to 122° F.

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MCD: or Millicandela, is used to rank/denote the brightness of an LED. 1000mcd is equal to one Candela. The higher the mcd number, the brighter the light the LED emits.

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Nanometers: or nm. Used to measure the wavelengths of light. The lower the wavelength eg. 400nm the bluer and stronger the light source. Longer wavelengths above 600nm are red. Above 680nm, they fall into the InfraRed category, which is colorless to our eyes. White LEDs have no specific wavelength. They are measured by the color of white against the chromaticity scale.

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Operating Life: usually refers to the number of hours a specific type of LED is expected to be operational. With high powered LEDs, that usually means life after it loses 10-15% or more rated output after 1000 or more hours of run time.

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Printed Circuit Board (PCB): are made from various materials including fiberglass and aluminum. The pcb has an electrical circuit imprinted in silver etching. That circuit says how the LED will operate. The pcb is also the platform by which LEDs are employed in various applications. It can be a rigid board or flexible to twistable.

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Power Supply: and Transformer and Voltage adapter apply to the electrical conversion of 110/120/240vac line power into 12vdc that will then be applied directly to the LED light product. Power Supplies are rated according to the current/amperage load capacity each will handle. It is an electrical or electro-mechanical device and is sometimes referred to as a LED Driver.

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PWM: Pulse Width Modulation with regards to LEDs means that the LED will be pulsed or strobed at a rate so fast that the eye will see the light as being constantly on. In fact it is not. This pulsing or turning the LED on and off lowers the potential heat stress on the chemical that makes the light, thus allowing the LED to perform longer than anticipated. This is why we strongly recommend a dimmer/PWM with every purchase of a 12vdc LED product.

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SMD/SMT: A type of low profile LED that is surface mounted to a PCB. These type LEDs are very powerful and range in lumen output from 35 up to 170 lumens. With the latest LED technology being applied today, these have shown to have the most promise in delivering light levels and coloring that we are used to having. Those smd LEDs we talk about, use and sell are in the .5 watt, 1 watt, 3 watt and 5 watt power range. When you see a 7 watt or 9 watt LED light, it will contain 1 watt LEDs x 7, or 1 watt LEDs x 9, or 3 watt LEDs x 3.

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SSL: SSL means Solid State Lighting. It does not use heating of a thin fragile filament to create light. Rather it uses electrical current passing through a chemical that will get excited and thus emit light.

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Task Lighting/Lamp: A LED light used to specifically light a particular area used for work or reading. Typically found in the form of a desk, floor, or clamp-on lamp, it can be a high powered LED light in any form.

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UV-A: (380–315 nm), also called Long Wave or "blacklight" because it is invisible to the human eye. Can cause skin irritation and fading of fabrics.

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UV-B: (315–280 nm), also called Medium Wave radiation. Can cause severe damage to the skin and human eye through exposure.

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UV-C: (← 280 nm), also called Short Wave or "germicidal" for its ability to destroy even bacterial life forms. Extremely hazardous to all life forms due to its ability to cause immediate damage to cellular DNA.

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Voltage: The rate at which energy is drawn from a source that produces a flow of electricity (amperage) in a circuit. The difference in electrical charge between two points in a circuit is expressed as volts.

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Voltage Regulator: A device which limits or controls and stabilizes the voltage being applied to a using unit such as LED lights and motors. Regulators also take higher voltages than required and reduces it to the working voltage that makes a specific product run correctly. In many instances a lack of a Voltage Regulator will allow higher voltage than a product can work with and will cause irreparable damage.

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Volts: The International System unit of electric potential and electromotive force, equal to the difference of electric potential between two points on a conducting wire carrying a constant current of one ampere when the power dissipated between the points is one watt.

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Volumetric Lighting: The term “Volumetric Lighting” simply refers to lighting that is less directional and more uniform throughout the entire volume of a space. Volumetric lighting extends beyond the work plane to adequately illuminate the entirety of the space, resulting in a better balance of luminance through the visual field. The space feels brighter, larger, more public, and more relaxing. Facial rendering is more natural, consistent, and complimentary. Shadows tend to be softer and less pronounced, and the appearance of the space is less defined by sharp, arbitrary transitions in surface brightness. Volumetric lighting does a better job of rendering architecture, its contents, and its occupants true to form.

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Waterproof: meaning the LED product can be submerged into calm water but there is a limited depth as stated for each specific product, and must be specifically stated for "submersion". It also means that the product is made to withstand water being splashed onto it like rain, or having snow on it. These products will be made of high grade stainless steel, aluminum, or high strength plastics.

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Watts: The unit for measuring electrical power. It defines the rate of energy consumption by an electrical device when it is in operation. The energy cost of operating an electrical device is calculated as its wattage times the hours of use. In single phase circuits, it is related to volts and amps by the formula: Volts x Amps x PowerFactor = Watts.

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Watt per LED: It can be confusing when two watt numbers are used in product specifications. For the application to smd high powered LEDs, the 1 watt, 3 watt, 5 watt, etc, refers to the power consumption of that specific LED installed in that product. The watt numbers expressed as light output are a comparison to an incandescent light bulb light output, eg; a 60 watt light output is equal to a 60 watt incandescent light bulb. The Watt Output is equipment measured.

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Weatherproof: meaning the product will take water splashing and high humidity without deterioration to the LED or circuit. LED product cannot be submerged into water.

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White: White is defined by Kelvin Temperature or Degrees Kelvin. Most will say that a Kelvin Temperature of 6000k plus is white with a bluish tint. And let's say that 5000k -5500k is daylight/sunlight white. At 4200k-4500k, it is called cool white. At 2800-3300k, it's warm white, which is the color temperature most incandescent light bulbs emit.

From 5500k on down the scale, the color becomes "warmer" due to the dominance of red and yellow hues. In the opposite direction, whites will have cooler colors like blues and green becoming more apparent, thus they are called cool whites.

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