~ Glossary of Terms ~

Accent Lighting

Accent lighting focuses light on a particular area or object. It is often used to highlight paintings, art or other artefacts. The brighter light from the accent lights helps to create a visual interest within a room or space.

Ambient Lighting

Ambient lighting, or what is commonly called general lighting, serves as the primary source of light for a certain room. It is the foundation of all the lighting of a room. Aside from the basic lighting functionality, ambient lighting improves the sense of warmth and depth of a room or space.

Amp (Ampere)

The ampere (SI unit symbol: A; SI dimension symbol: I), often shortened to Amp, is the SI unit of electric current (quantity symbol: I, i) and is one of the seven SI base units. It is named after André-Marie Ampère (1775–1836), a French mathematician and physicist, considered the father of electrodynamics.

In practical terms, the ampere is a measure of the amount of electric charge passing a point in an electric circuit per unit time with 6.241 × 1018 electrons, or one coulomb per second constituting one ampere.

The practical definition may lead to confusion with the definition of a coulomb (i.e., 1 ampere-second), but in practical terms, this means that measures of a constant current (e.g., the nominal flow of charge per second through a simple circuit) will be defined in amperes (e.g., "a 20 mA circuit") and the flow of charge through a circuit over a period of time will be defined in coulombs (e.g., "a variable-current circuit that flows a total of 10 coulombs over 5 seconds"). In this way, amperes can be viewed as a flow rate, i.e. number of (charged) particles transiting per unit time, and coulombs simply as the number of particles.

Beam Angle

Beam angle denotes how wide the light spreads. It is measured in degrees and the bigger the number, the wider the beam of light.

Candela

The candela (cd) is a standard measure of luminous intensity to allow direct comparison of the ‘brightness’ of different light sources.

Cool White

A term used to describe a particular colour temperature range. Cool white lighting has a colour temperature of between 3500K – 5000K and emits a bluer, more intense light.

CRI

A color rendering index (CRI) is a quantitative measure of the ability of a light source to reveal the colors of various objects faithfully in comparison with an ideal or natural light source. Light sources with a high CRI are desirable in color-critical applications such as picture lighting and lighting of art.

Correlated Colour Temperature

CCT stands for Correlated Colour Temperature (which is often shortened to just Colour Temperature). It defines the colour, not brightness of a light source, and is measured in kelvin (K) and NOT degrees Kelvin (°K) which is a measurement of temperature. Every white light has its own hue that falls somewhere along an amber to blue spectrum

Diffuser

A cover or filter placed over a light source designed to soften (or diffuse) the light being emitted.

Driver

An LED driver is a self contained power supply which regulates the power required for an LED or array of LEDs. There are two main types of driver, constant current and constant voltage. As the name suggests a constant current driver will deliver a constant current over a voltage range whilst6 a constant voltage driver will deliver a constant voltage over a current range. Both types of drivers can have a multitude of dimming protocols from triac trailing and leading edge (mains dimming), 0-10v, Dali and DMX to name a few.

Infrared Light (IR)

Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR propagates energy and momentum, with properties corresponding to both those of a wave and of a particle, the photon. IR like UV can be harmful to paintings and artifacts which is why it should be removed from any light source being used in these lighting applications. Typically in museums, fibre optic lighting is used as there is no UV, IR or heat at the light source. For more information about fibre optic lighting please click here

Intelligent Battery Power Supply

A rechargeable battery pack combined with a uniquely sophisticated control and monitoring system which regulates the power drawn from the batteries so that a consistent light level is emitted without the usual irritations of the light fading as the battery is discharged, additionally there is no flickering or color-shift. The picture light is controlled via remote control using RF signal protocols for the on/off, dimming and memory functions. For more information on our battery-powered picture lights please click here

LED

A light-emitting diode (LED) is a semiconductor light source that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (corresponding to the energy of the photons) is determined by the energy required for electrons to cross the band gap of the semiconductor. White light is obtained by using multiple semiconductors or a layer of light-emitting phosphor on the semiconductor device.

LED Module

The LED module is a component of our Gallery Range of Picture Lights. The LED module can be independently tilted and can be placed anywhere along the power rail within the Gallery Picture Light head. The LED module also has interchangeable lenses, combined with being movable within the head allows for total lighting distribution control across even the most demanding canvases to deliver perfect illumination across the canvas.

Lumen

The lumen (symbol: lm) is the SI derived unit of luminous flux, a measure of the total quantity of visible light emitted by a source per unit of time. Luminous flux differs from power (radiant flux) in that radiant flux includes all electromagnetic waves emitted, while luminous flux is weighted according to a model (a "luminosity function") of the human eye's sensitivity to various wavelengths. Lumens are related to lux in that one lux is one lumen per square meter.

Luminaire

A complete electric light unit or fixture. A luminaire includes the lamp, internal wiring, reflectors, lens and any additional components required to deliver light.

Lux

The lux (symbol: lx) is the SI derived unit of illuminance, measuring luminous flux per unit area. It is equal to one lumen per square meter. In photometry, this is used as a measure of the intensity, as perceived by the human eye, of light that hits or passes through a surface.

Retrofit

Upgrading an existing light fixture, usually by replacing the conventional lamp within the light fitting to LEDs, this improves its efficiency, performance, and longevity as well as recycling the old light fitting.

Ultra Violet (UV)

Ultraviolet (UV) is a form of electromagnetic radiation, shorter than that of visible light, but longer than X-rays. UV radiation is present in sunlight, and constitutes about 10% of the total electromagnetic radiation output from the Sun. UV can be very damaging to artwork and paintings and should be removed from any light source used in this type of illumination.

Voltage

Voltage is defined so that negatively charged objects are pulled towards higher voltages, while positively charged objects are pulled towards lower voltages. Therefore, the conventional current in a wire or resistor always flows from higher voltage to lower voltage.

Historically, voltage has been referred to using terms like "tension" and "pressure". Even today, the term "tension" is still used, for example within the phrase "high tension" (HT) which is commonly used in thermionic valve (vacuum tube) based electronics.

Warm White

The term is generally used for lighting with a colour temperature of around 2700K - 3000K. It is the traditional yellowish colour of a conventional lamp

Watt

Measurement unit for the electric power consumed . A one watt lightbulb, for example, will change one joule of electrical energy into light energy (and some heat/sound) every second. The more watts, the more energy used per second.