Accent Lighting

Directional lighting to emphasize a particular object or to draw attention to a part of the field of view.


The dissipation of light within a surface or medium.

Alternating Current (AC)

Flow of electricity which cycles or alternates direction many times per second. The number of cycles per second is referred to as frequency. Most common frequency used in this country is 60 Hertz (cycles per second).

Ambient Lighting

Background or fill light in a space.

Amperes (amps)

The unit of measurement of electric current.

Back Lighting

The illumination provided for scenery in off-stage areas visible to the audience.


An opaque or translucent element that serves to shield a light source from direct view at certain angles, or serves to absorb unwanted light.


An auxiliary device consisting of induction windings wound around a metal core and sometimes includes a capacitor for power correction. It is used with fluorescent and HID lamps to provide the necessary starting voltage and to limit the current during operation.


Is not a LED. A bulb is a light bulb, an MR17 or E27 base light bulb. 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.

Bulb Base

The part of the bulb that is used to set it into place and to make contact with electricity. There are many types and sizes. Most common are E27/E27, USA and European standard household size, or medium base as it often is called. The 26 or 27 equates to the diameter measurement in millimeters of the threads of a screw in base bulb. This type of bulb includes the PAR20, PAR30 and PAR28 types. There are MR16 and MR11 type base LED bulbs as well as GU10's. There are also E12 candelabra base LED light bulbs


The unit of measurement of luminous intensity of a light source in a given direction.


Luminous intensity expressed in candelas.


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. Sometimes called color temperature, it is measured in Kelvin. It can also be defined by using x and y coordinated against a standard chromaticity scale developed by the Commission Internationale de l'clairage (CIE).

Class "P" Ballast

Contains a thermal protective device which deactivates the ballast when the case reaches a certain critical temperature. The device resets automatically when the case temperature drops to a lower temperature.


The measurement of color.

Color Rendering Index (CRI)

Measure of the degree of color shift objects undergo when illuminated by the light source as compared with the color of those same objects when illuminated by a reference source of comparable color temperature.

Color Temperature

Incandescent PAR lamps that use a special coating (dichroic interference filter) on the reflectorized potion of the bulb to allow heat to pass out the back while reflecting only visible energy to the task, thereby providing a "cool beam" of light.


Special fluorescent lamp ballast, which when used with a dimmer control, permits varying light output.

Dimming Ballast

12 VDC dimmers are used with LED lights powered by 12 VDC. PWM built in as is an on/off switch. These dimmers are installed in between the power supply output and the fixture input. Customers also have the option of using a dimmable magnetic transformer in conjunction with a 120VAC standard dimmer. Many LED fixtures are on the market today that are able to be dimmed directly at 120 VAC.

Direct Current (DC)

Flow of electricity continuously in one direction from positive to negative.

Direct Lighting

Lighting involving luminaires that distribute 90 to 100% of emmited light in the general direction of the surface to be illuminated. The term usually refers to light emitted in a downward direction.

Emergency Lighting

Lighting system designed to provide minimum illumination required for safety, during power failures.

"ER" (Elliptical Reflector)

Lamp whose reflector focuses the light about 2" ahead of the bulb, reducing light loss when used in deep baffle downlights.


A system designed for lighting a scene or object to a luminance greater than its surroundings. It may be for utility, advertising or decorative purposes.

Footcandle (fc)

The unit of illuminance when the foot is taken as the unit of length. It is the illuminance on a surface one square foot in area on which there is a uniformly distributed flux of one lumen.


A set of striplights at the front edge of the stage plateform used to soften face shadows cast by overhead luminaires and to add general toning lighting from below.

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.


Unit of measurement for color temperature. The Kelvin scale starts from absolute zero, which is -273 Celsius.

Kilowatt-Hour (KWH)

Unit of electrical power consumed over a period of time. KWH = watts/1000 x hours used.


An artificial source of light (also portable luminaire equipped with a cord and plug).

Lamp Efficacy

The ratio of lumens produced by a lamp to the watts consumed. Expressed as lumens per watt (LPW).


LED stands for 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 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 are placed on a circuit board or other material that allows electricity to pass through at a specific voltage and current and with components required to operate them at specific voltages. The LED shown on the left is a first generation 3mm LED. See SMD LED definition below.

LED Bars

Refers to a solid strip of material on which LEDs have been soldered 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 plastic, aluminum or metal composites with various types of lens/covers.

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 wires called leads. One is negative, the other positive. In RGB products, there are four wires - red, blue, green and common.

LED Drivers

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, strips, clusters, fluorescent tube replacements and so forth.

LED Strips

LED strips are usually printed circuit boards with LEDs soldered to the board. The strips can be rigid or flexible and without any enclosure to protect the LED and circuit. Here is where our crown molding and aluminum channel come into play.

Low Voltage Lamps

LED lamps that operate at 6 to 12 volts.


How well a LED product 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.

Lumen Maintenance

The unit of luminous flux. It is the luminous flux emitted within a unit solid angle (one steradian) by a point source having a uniform luminous intensity of one candela.


A complete lighting unit consisting of a lamp or lamps together with the parts designed to distribute the light, to position and protect the lamps and to connect the lamps to the power supply.

Luminaire Efficiency

The ratio of luminous flux (lumens) emitted by a luminaire to that emitted by the lamp or lamps used.


The metric unit of illuminance. One lux is one lumen per square meter (lm/m2).

"PAR" Lamps

Parabolic aluminized reflector lamps which offer excellent beam control, come in a variety of beam patterns from very narrow spot to wide flood and can be used outdoors unprotected because they are made of "hard" glass that can withstand adverse weather.

Power Supply

Transformer or Voltage Adapters apply to the electrical conversion of line voltage to low voltage 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 electromechanical device.

"R" Lamps

Reflectorized lamps available in spot (clear face) and flood (frosted face).


The process by which the direction of a ray of light changes as it passes obliquely from one medium to another in which its speed is different.


A type of low profile LED that is surface mounted to a PCB. These type LEDs are very powerful. These have the most promise in delivering light levels and coloring that we are used to having.

View Angle

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. Volts is defined as a 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.


Means that the LED product can be used in wet conditions. However, that varies from product to product. Refer to the IP Rating Chart. By no means does it mean submersible. As to product that will be cut in the field, it is up to the installer to be sure that any cuts are properly sealed.


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 the wattage times the hours of use. In single phase circuits it is related to volts and amps by the formula: V x A x PF (power factor) = W. More and more we are getting away from stating brightness of a product by use of incandescent watts comparisons. Consumers now are used to lumen ratings which are more pertinent today.