Glossary Of Terms

Accent Lighting: Narrow beam angle intended to draw attention to a specific object or area.

Alternating Current (AC): Electrical current in which the flow of electric charges continually reverses direction.

Ambient Lighting: Lighting designed to provide uniform light levels throughout and area.

Backlighting: Use of light source to illuminate from behind without protrusion through the panel.

Ballast: The device that limits amount of current in an electrical circuit.

Beam Angle: Size of the cone of light produced by lighting source measured in degrees.

Can Light:  Another name for a recessed light or down light, which is a fixture, installed into a hollow opening in a ceiling, Short for Canister Light.

CE: Certifies product has met EU (European) consumer safety, health and or environmental requirements.

CFL: Compact Fluorescent which consume less energy than Incandescent with the negative aspect of Mercury/Poison content.

Color Temperature (CT): This is a measurement of the Yellowness or Blueness of a White light source based on a Kelvin number.

Yellowish White described as Warm White is compared to Incandescent Lamps, which have a lower Kelvin temperature number around 2700-3000 range.

White and Bluish White described as Natural White and Cold White have a higher Kelvin Temperature of 5000-7000.

Cool White: Kelvin color temperature of 5500-7000

CRI: Color Rendering International system to rate lighting device ability to render object colors.

Higher the CRI (based on a 0-100 scale). The greater the color fidelity of the lighting source.  Natural outdoor light has a CRI of 100.

Diffuser: Optical element used to mix light ray to improve uniformity of light.

Direct Current (DC): Electrical current which the flow of electric charge moves in one direction only.

Down Light: Light source set in a metal cylinder. Mounted or recessed into the ceiling so the beam of light is directed downward.

Driver: LED power supply providing either a constant level of current or a constant level of voltage.

E26/E27: Edison Screw fitting system designated at standard screw-in bulb bases. Also referred to a “Medium” or “Standard” Base.

Flood Light: A lamp that provides a broad beam intended to light a general area.

Fluorescent Tube: Light source consisting of a glass tube filled with low pressure mercury vapor. Electrical discharge through the vapor produces ultraviolet light that excites phosphor materials on the inside of the tube, which emit visible light.

Flux: Sum of Lumens emitted by a light source.

Foot-candle (FC): Unit of light falling onto a surface. One foot-candle is the light level on a surface one-foot from a standard candle.

GU: A bi-pin base code. Each Pin has two diameters. Being larger near the ends in order to twist and lock into position in the socket. GU10’s are one of the most common base products, almost always 110/120V AC.

Heat Dissipation: This is the transition of thermal energy form a hotter object to a cooler object. With LED heat sinks made from high quality aluminum and other alloys accomplish this.

High Intensity Discharge (HID): Electrical lamp filled with gases and other compounds in which an electric arc is passed between tungsten electrodes to produce light.

High Pressure Sodium (HPS): High Intensity discharge lamp offering a warm Correlated Color Temperature (CCT) high level of efficiency, ling life with very modest levels of CRI.

Incandescent Lighting: Light produced when a filament is heated to incandescence using electric current. Incandescent lighting is very inefficient since most of the energy is wasted as heat rather than light

Kelvin (K): Unit of temperature starting from absolute zero.

Kelvin Temperature: Color measure as to Yellowness or Blueness of the color white. The higher the Kelvin temperature the more blue than White.

Kilowatt (KW): Measure of electrical power equal to 1000 Watts.

LED: Light Emitting Diode solid-state semiconductor device that converts electrical energy directly into light.

Lumen: Measurement of luminous flux of quantity of light emitted by a source. The brightest light bulbs have higher lumens.

Lumen Maintenance: Describes how long a light source will retain a certain percentage of its initial Lumen output.

Luminous Efficacy: Measurement of how effective the light source is in converting electrical energy to Lumens of visible light. Usually expressed in Lumens per watt (LPW)

Lux:  Unit of luminance or density of light falling onto a surface. One lux is equal to one lumen per square meter.

Metal Halide (MH): High Intensity light source produced by the radiation from mercury, plus halides of metals such as sodium, scandium, indium, and symposium.

MR: A bi-pin base code for a 2 sharp pin push in base. Almost always 12V Product. The MR16 LED lamps are a very popular replacement for Halogen.

Natural White:  Light with a Kelvin Temperature between 4500 and 5500.

PAR Lamp: Acronym for a Parabolic Reflector. PAR20, PAR30, PAR38 are Most Common.

Power Supply: Device that supplies electrical or energy.  Most LED Power Supplies Convert Line Voltage (110AC) to 12 & 24V DC.

RGB: Acronym for Red, Green, and Blue. These are the 3 primary colors of light. RGB’s use Combinations of these colors to create wide variety of other colors.

RoHs Compliance: Restricts the use of certain dangerous substances commonly used in electrical and electronic equipment.

SMD (Surface Mount): LED’s are soldered to the surface of the circuit board. The LED Die is integrated into the package design. Surface Mounted LEDs can be assembled faster and with better quality than Dip through-Hole Components.

Spotlight: A lamp that produces a narrow beam angle designed to illuminate a specific targeted area.

Tube Light: Term used to describe a fluorescent tube. Most typical sizes are T5, T8, T10 and T12.

T indicates the shape of the bulb is tubular. Typical diameters T5 =5/8 ” T8 =1″ T12=1 1/2″

Traditionally the T8, T10, and T12 use the dual pin G13 Socket.

Ultraviolet (UV): Invisible radiation that is shorter in wavelength and higher in frequency than visible violet light. UV rays are light waves that are similar to the light from the sun. UV radiation can cause oxidation, fading of colors of furniture, carpet, draperies and artwork.

Warm White: White color with a Kelvin temperature between 2800-3200.