Accent lighting: Draws attention to special features or enhances the aesthetic qualities of an indoor or outdoor environment.
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.
Ambient lighting: Provides general illumination indoors for daily activities, and outdoors for safety and security.
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.
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.
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.
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.
Dimmer: The use of dimmers and dimmer devices will reduces the wattage and output of lighting, which helps save energy.
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).
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.
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).
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.
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.
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.
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.
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.
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.
Max Rated Temperature: 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.
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.
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.
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.
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.
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.
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.
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.
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.