Alternating Current is an electrical current with cyclically reversing direction, as opposed to direct current, the direction of which remains constant. The usual waveform of an AC power circuit is a sine wave.

Accent Lighting
Specific "highlighting" to emphasize objects and create a specific mood.

(Amp) - The physical unit for measuring rate of electrical current.

Beam Angle
The angular dimension of a lamp encompassing the central part of the beam out to the angle where the intensity is 50% of the maximum.

(Color Bin) - The systematic dividing of an LED distribution of performance parameters like Flux, Color, CCT or VF into smaller groups that meet the requirements.

Refers to the outer glass bulb containing the light source.

(Cd) - The luminous intensity in a given direction as defined by the international metric standard (SI). The term defines a standard candle of a fixed size and composition as a basis for evaluating the intensity of other light sources.

A very small square of semi-conducting material, the active, light-emitting component of an LED.

Measure to identify the color of a light source, typically expressed as (x,y) coordinates on a chromaticity chart.

(Dominant Wavelength) - The color / dominant wavelength is a quantitative measure of an LED color as perceived by the human eye and is usually measured in nanometers (a billionth of a meter). In order to specify an LED, the required color range has to be specified.

Color Rendering Index
(CRI) - An international system used to rate a lamp's ability to render object colors. The higher the CRI (scale from 0 -100), the richer the colors generally appear.

Color Spectrum
All wavelengths perceived by human sight, usually measured in nanometers (nm).

Color Temperature
A number indicating the degree of "yellowness" or "blueness" of a white light source (LED). Measured in kelvins, it represents the temperature an incandescent object must reach to mimic the color of the lamp.

Cool White
A term loosely used to denote a color temperature of around 4100 K.

Direct Current is an electrical current where the direction remains constant, as opposed to Alternating Current, the direction of which reverses cyclically.

A translucent optical element, made of glass or plastic and used to mix light rays to improve uniformity.

Through varying the power, the lamp's lumens can be varied while maintaining reliability.

Electronics used to stabilize power illumination sources.

(A19) The Edison screw fitting is a system of lightbulb connectors, referring to the diameter in millimeters. Common sizes are: E10, E12, E14, E26,...
(Luminous efficacy) - A measurement of how effective the light source is in converting electrical energy into visible light, defined in lumens per watt (lm/W). This measure is partial to human eye sensitivity and gives more weight to the yellow region of the spectrum and less weight to the blue and red region.
The efficiency of a light source is the fraction of electrical energy converted to light. A 100 watt incandescent bulb for instance converts 7% of the electrical energy into light.

(Compact fluorescent lamp) - A lamp filled with inert gases like argon or krypton, utilizing an electric discharge through low pressure mercury vapor to produce ultraviolet (UV) energy. The UV excites phosphor materials applied as a thin layer on the inside of a glass tube which makes up the structure of the lamp. The phosphors transform the UV light to visible light.
(GX5.3) The GX5.3 is the standard code for the most common base / socket of the MR 16, and stands for the bi-pin distance in mm from the center of one pin to the other.
Standard socket format used for high-voltage halogen and LED spotlights with bayonet mount (twist & lock). Usually these bulbs need no extra transformer as each lamp has a transforming device inside. The distance between the centers of both bayonet pins is 10 mm.
Bayonet mount socket similar to GU 10 with 24 mm center distance of bayonet pins. Usually designed for ENERGY STAR requirements, an up-coming usage for LED lights now

Halogen Lamp
A halogen lamp is an incandescent lamp with a filament that is surrounded by halogen gases, such as iodine or bromine. Halogen gases allow the filaments to be operated at higher temperatures and higher efficacies.

High Intensity Discharge
(HID) Lamp - A mercury, metal halide and high-pressure sodium lamp. HID lamps contain compact arc tubes which enclose various gases and metal salts operating at relatively high pressures and temperatures.

Incandescent Lamp
A light source that generates light utilizing a thin filament wire (usually of tungsten and in a vacuum), heated to white heat by electric current.

The preferred LED (Light Emitting Diode) - semiconductor technology containing Indium, Gallium, and Nitrogen compounds to produce blue and white-colored LED light sources.

A unit of temperature starting from absolute zero, parallel to the Celsius (or Centigrade) scale. 0° C is 273°K.
Kilowatt Hour
(kWh) - The standard measure of electrical energy typically used by electrical utilities as billing unit for electricity use.
A light-emitting diode (LED) is a semiconductor diode that emits light when an electrical current is applied in the forward direction of the device. Some LED's are coated with fluorescent materials to change the color characteristics of the emitted light. Most LEDs have a lense to focus the emitted light.
(Lm) - is the international (SI) unit of luminous flux or quantity of light and equals the amount of light that is spread over a square foot of surface by one candle power when all parts of the surface are exactly one foot from the light source. A dinner candle provides about 12 lumen.
(Lx) - A unit of illuminance or light falling onto a surface. One lux is equal to one lumen per square meter.
LED's are available in either (threaded?)leaded-through-hole, or surface-mount packages. Through-hole LED's are ideal for wave solder circuit board applications, whereas, surface-mount packages are best used with reflow assembly. SMD devices are also useful when package size constraints are an issue.
PAR30, PAR38
Lamp - PAR is an acronym for parabolic aluminized reflector. PAR lamps are usually used for outdoor lighting. They have a parabolic metallic coated reflector, the size (e.g."30") stands for the diameter in eighths of an inch. "30" = 3-3/4 inch.
An inorganic chemical compound processed into a powder and deposited on the LED, also used for Compact Fluorescents.
R30, R38
Flood lamps for indoor lighting, usually used in incandescent recessed lighting, dimmable with a standard incandescent dimmer. The size stands for the diameter in eighths of an inch.
The abbreviation for Surface Mounted Device. LED units, which are soldered directly onto the plate. (occurs frequently with 3in1 LEDs).
Solid-State Lighting
(SSL) - refers to a type of lighting that utilizes LEDs, OLEDs (Organic LEDs) or PLEDs (Polymer LEDs) The term refers to the fact that light in an LED is emitted from a solid object - a block of semiconductor in case of LEDs - rather than from a vacuum or gas tube, as is the case in traditional incandescents or fluorescents. SSL creates visible light with reduced heat generation or parasitic energy dissipation. In addition, its solid-state nature provides for greater resistance to shock, vibration, and wear, hereby significantly increasing its lifetime.
Most common Fluorescent Lighting, where the letter refers to the shape of the bulb (tubular) and the ''12' stands for the diameter of the bulb in eighths of an inch (12 eighths = 1 1/2 inches)
Thermal management
Controlling the operating temperature of the product through specific design, like a heat sink and improved airflow for cooling.
The term used to describe the electrical potential difference between oppositely charged conductors.
Forward Voltage (VF)
The voltage across a diode for a given forward current.
Warm White
A description of light with a correlated color temperature between 2700K and 3500K, usually perceived as slightly yellow.
The unit of electrical power as used by an electrical device during its operation. Many lamps come with rating in watts to indicate their power consumption.
(Dominant wavelength) - see "color"