Lighting technology terms...
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z
Beam angle
Beam angle refers to the area within which light is emitted from a light source. It indicates the angle at which the light emanates from the light source and spreads.
The beam angle depends on the specific construction and design of the light source. It can be either a narrow or a wide beam angle.
A narrow beam angle means that the light is focused and directed in a specific direction. It produces a concentrated, high-intensity beam of light. This type of light source is well suited to illuminate specific areas or objects in a targeted manner or to set accents.
A wide beam angle, on the other hand, spreads the light over a larger area. It creates a diffuse light pattern that spreads over a wide space. This type of light source is more suitable for general room lighting or for large-area illumination.
The beam angle of a light source can be specified in degrees. A smaller beam angle, for example 15 degrees, produces a focused beam of light. A wider beam angle, such as 120 degrees, creates a wider, more diffuse light pattern.
The beam angle is an important factor in lighting planning and design. It influences the distribution of the light, the light intensity in different places and the lighting effects that can be created. Depending on the application and the desired lighting situation, the selection of the beam angle can play an important role.
Candela
Candela (cd) is the base unit for luminous intensity in the International System of Units (SI). Luminous intensity indicates how much light a light source emits in a specific direction.
The candela defines the luminous intensity of a light source in a given direction as a luminous flux of 1 lumen (lm) emitted by that source at a solid angle of 1 steradian (sr). The steradian is a unit of measurement of the solid angle that describes the area that the light covers.
The candela is independent of the distance to the light source and only refers to the emitted light intensity in a certain direction. It is particularly useful when measuring the brightness or intensity of light rays, or comparing light sources pointed in a specific direction.
The luminous intensity of a light source can vary depending on the direction and distribution of the light. A flashlight with a narrow beam can have a higher luminous intensity in the direction it is aimed, while a light bulb with a wider beam angle can have a lower luminous intensity because the light is spread over a larger solid angle.
The Candela unit is used in various fields including lighting engineering, photometry, optics and other fields where the intensity of light needs to be measured or specified. It helps to quantify the brightness of light sources and to characterize the lighting properties.
Color temperature
Color temperature is a term used to describe the color of light emitted by a light source. It is measured in Kelvin (K) and indicates whether the light appears warm or cold.
Color temperature is based on the concept of the black body radiator, which is an object that absorbs all light and then emits it again depending on its temperature. The higher the temperature of the blackbody radiator, the bluer the emitted light becomes. Conversely, lower temperatures produce warmer colors ranging from yellow to orange to red.
In lighting technology, color temperature is used to describe the light color of lamps and lights. The most common color temperatures used are:
arm White (2700K-3000K): This light has a cozy yellowish or warm color. It is often used in living rooms, restaurants or areas where a relaxed atmosphere is desired.
Neutral white (3500K-4000K): This color temperature produces a white light that is perceived as neutral. It is often used in offices, schools or other work environments where good visibility and color rendering are required.
Cool White (5000K-6500K): This color temperature produces a cool, bluish light. It is often used in environments where high brightness, concentration or color rendering is required, such as in hospitals, manufacturing plants or outdoor areas.
It is important to note that color temperature is not a statement of the actual color of the light emitted, only the perceived "warmth" or "coldness". The Color Rendering Index (CRI) is another important metric that indicates how well a light source renders the colors of objects.
The choice of color temperature depends on the specific requirements and atmosphere of the room. Different color temperatures can affect people's mood, perception of spaces, and productivity.
Diffuser foil
A diffuser foil is used in lighting technology to spread the light from a light source more evenly and reduce harsh shadows or glare. It is often placed on fixtures, lamps or light sources to diffuse the light and create a softer, more diffused lighting.
Here are some uses and benefits of using a diffuser sheet:
Softer Lighting: A diffuser sheet helps to diffuse and spread the direct light from a light source, creating a more even and soft lighting. This minimizes harsh shadows and makes the light easier on the eye.
Reduce glare: A diffuser film can help to reduce glare, especially with bright or intense light sources. It diffuses the light so that it does not go directly into the viewer's eyes and allows for a more comfortable perception of light.
Control light distribution: Depending on the type of diffuser film, it can also be used to control and adjust light distribution. Different types of diffuser films have different transparency properties and surface structures that can affect light refraction. This allows specific lighting effects to be created or specific areas to be specifically illuminated.
Creative lighting design: diffuser foils also offer opportunities for creative lighting design. By combining different types of film, colors or structures, specific lighting effects can be achieved to create the atmosphere, mood or aesthetics of a room.
There are different types of diffuser sheets on the market including frosty or opaque sheets, prismatic sheets, diffuser sheets and more. The selection of the right diffuser film depends on the specific requirements, the light source and the desired lighting effect.
It is important to note that a diffuser sheet can also cause some light loss as some of the light is absorbed or scattered by the scattering. This should be taken into account when planning and designing the lighting.
EVG - electronic ballast
An EVG stands for "electronic ballast". It is an electronic switching device used in lighting to regulate the power supply of fluorescent lamps, compact fluorescent lamps (CFL) and some types of light emitting diodes (LED).
Compared to conventional ballasts, such as magnetic ballasts (LLG), electronic ballasts offer a number of advantages:
Energy efficiency: Electronic ballasts are generally more energy efficient than magnetic ballasts. They use less electricity and convert a higher percentage of the input energy into light. As a result, they can contribute to reducing energy consumption.
Flicker-free light: By using high-frequency circuits, electronic ballasts produce flicker-free light. Unlike magnetic ballasts, which operate at a lower frequency and can cause visible flicker, electronic ballasts provide a stable and even light output.
Instant start: ECGs allow lamps to start instantly without delay or flickering. This is particularly useful in environments where fast and reliable lighting is required.
Longer lamp life: By precisely controlling current and voltage, electronic ballasts can extend lamp life. They reduce the stress on the lamps and minimize the likelihood of failures due to overload or unnecessary wear.
Electronic ballasts are available in different versions to suit different lamp types. They can exist as independent ballasts or as an integrated part of a luminaire or lamp.
It is important to note that not all fluorescent or LED lights require an electronic ballast. Some lamps, particularly older models, may still require conventional ballasts. When selecting and installing an ECG, it is therefore advisable to take into account the specific requirements of the lamps used.
EX-proof lights
ATEX or EX lights are equipment that is approved for areas in the gas EX and dust EX zones in accordance with the ATEX Directive 2014/35/EU. For which ATEX areas the respective equipment can be used results from the ATEX marking which is usually attached to the equipment.
General lighting
General lighting refers to the basic lighting of a room or environment that ensures uniform illumination of the entire area. Its purpose is to ensure adequate brightness and visibility in a space without focusing on specific areas or functions.
General lighting is used in almost all spaces and environments, including homes, offices, shops, schools, hospitals, public facilities and industrial areas. Their goal is to provide a basic brightness that enables people to move safely and comfortably in a room, to carry out everyday tasks and to perceive their surroundings.
Luminaires or light sources with a wide beam angle are generally used in general lighting in order to distribute the light evenly and minimize the formation of shadows. Illuminance, measured in lux, is set according to the needs of the space and activities. There are standards and guidelines that propose minimum recommended illuminance levels for different types of spaces to ensure adequate general lighting.
General lighting can be achieved using different types of light sources, such as ceiling lights, recessed lights, pendant lights or even indirect lighting systems. The choice of lighting solutions depends on the needs of the space, aesthetics, energy efficiency and other factors.
It is important to combine general lighting with other types of lighting, such as accent lighting or task lighting, to achieve versatile and well-balanced lighting in a space.
Illuminance
Illuminance is a measure of the amount of light falling on a given surface. It indicates how bright or intense the light is at a certain point and is measured in lux (lx) units.
Illuminance is influenced by the light source, the distance from the light source and the propagation of the light. The closer a light source is to a surface or the larger the beam angle of the light source, the higher the illuminance on the surface.
One lux corresponds to one lumen per square meter (lx = lm/m²). A lumen (lm) is a unit of luminous flux that indicates how much light a light source emits in total. However, illuminance is specific to the surface on which the light falls and takes into account the propagation of the light across the room.
Illuminance is used in various application areas such as lighting design, architecture, workplace design, street lighting, plant cultivation and many other areas. There are standards and recommendations that suggest minimum illuminance levels for different activities and environments to ensure adequate brightness and visibility.
Illuminance is an important criterion for lighting quality and can have a significant impact on people's visual perception, well-being and performance. Adequate illuminance is particularly important in workplaces, educational institutions, retail, healthcare facilities and other environments where good visibility and safety must be ensured.
IP degrees of protection
The IP rating (Ingress Protection) is a marking that indicates the degree of protection of electrical equipment against the ingress of foreign objects such as dust, dirt, water and other liquids. It is used to provide users with information about a device's suitability for specific environmental conditions and to evaluate its resistance to external influences.
The IP protection class consists of the letters "IP" followed by two digits. The first digit indicates the level of protection against ingress of foreign objects, while the second digit indicates the level of protection against ingress of water or moisture.
Here are some examples of what the digits mean:
IP20: protection against the ingress of solid objects with a diameter of more than 12.5 mm (e.g. fingers), but no protection against water.
IP44: protection against the ingress of solid foreign objects with a diameter of more than 1 mm and against splashing water from all directions.
IP67: Dust-tight (no ingress of dust) and protection against temporary immersion in water to a depth of 1 meter for limited periods.
IP68: Dust-tight (no ingress of dust) and protection against prolonged immersion in water under specified conditions, which may vary by manufacturer.
The exact meaning of each digit may vary depending on the device type and application. It is important to consider the specific requirements and the environment in which the device will be used to select the appropriate IP rating. IP rating is commonly used in electrical equipment, lights, outdoor electronics, industrial equipment, submersible equipment and many other applications where protection from dust and water is important.
It should be noted that a higher IP rating does not automatically mean that the device can also be used in every environment. It is important to follow the manufacturer's specifications and recommendations and to take additional protective measures if necessary to ensure safe and reliable use.
Kelvin
In lighting engineering, Kelvin (K) refers to the unit of measurement of the color temperature of light. The color temperature indicates whether the light appears warm or cold and is defined by the concept of the black body radiator.
A black body radiator is a hypothetical object that absorbs all light and re-emits it depending on its temperature. The color of the emitted light depends on the temperature of the blackbody radiator. At lower temperatures the light appears redder, while at higher temperatures it becomes more bluish.
Different color temperatures are used in lighting technology to adjust the lighting effect and create the desired atmosphere. Here are some common color temperatures and their typical uses:
Warm White (2700K-3000K): This light appears yellowish or warm. It is often used in residential areas, restaurants and hotels to create a cozy and relaxed atmosphere.
Neutral white (3500K-4000K): This color temperature produces a white light that is perceived as neutral. It is widely used in offices, schools and other work environments where good visibility and concentration are required.
Cool White (5000K-6500K): This color temperature produces a cool, bluish light. It is often used in hospitals, manufacturing facilities and outdoors where high brightness, visibility and color rendering are required.
It is important to note that color temperature alone is not indicative of the actual color of the light emitted, only how "warm" or "cold" it is perceived. The Color Rendering Index (CRI) is another important metric that indicates how well a light source renders the colors of objects.
When selecting light sources and planning lighting, it is important to consider the desired atmosphere, intended use and color rendering requirements to choose the right color temperature.
Lamp vs Luminaire
The terms "lamp" and "luminaire" are often used interchangeably to describe a light source or lighting device. However, there is a subtle difference between the two terms.
A lamp usually refers to the light source itself. It can be an incandescent lamp, an LED lamp, a fluorescent lamp or any other type of lighting element that produces light. A lamp is the actual component that converts electricity into light.
On the other hand, a luminaire refers to the complete lighting device that contains the lamp and related components such as the lampshade, reflector, switch and bracket. The luminaire includes the entire unit that generates, controls and distributes the light. It can be in the form of a table lamp, a ceiling lamp, a wall lamp or a floor lamp.
In other words, the lamp is the illuminant itself, while the fixture is the housing or container that contains the lamp and controls the light.
It is important to note that the term "lamp" is sometimes also used in common parlance to denote a luminaire. However, in technical jargon, a distinction is made between lamp and luminaire to clarify the difference between the light source and the lighting device as a whole.
LED
LED stands for "Light Emitting Diode". An LED is a semiconductor electronic device that produces light in the form of electroluminescent radiation when an electric current is passed through it.
Unlike conventional incandescent or fluorescent lamps, LEDs produce light in a different way. They are made of a semiconductor material, typically gallium arsenide, gallium phosphide, or indium gallium nitride. When current is passed into the LED, the electrons in the semiconductor material react, releasing energy in the form of light.
The advantages of LEDs compared to conventional lighting technologies are manifold:
Energy efficiency: LEDs are extremely energy efficient and convert a large part of the supplied energy into light. Compared to incandescent lamps, LEDs save a lot of energy and help reduce power consumption.
Longevity: LEDs have a long lifespan and can reach many thousands of hours of operation. They last significantly longer than traditional incandescent or fluorescent lamps, resulting in lower maintenance costs and reduced lamp replacement.
Compact Design: Because of their small size and low profile, LEDs can be used in a variety of shapes and applications. They can be used flexibly and enable innovative lighting solutions.
Instant Turn On: LEDs reach full brightness immediately when turned on, unlike some other lighting technologies that require a warm-up time.
Environmental friendliness: LEDs do not contain harmful substances such as mercury and do not emit UV or infrared radiation. They are therefore more environmentally friendly and help reduce environmental impact.
LEDs are used in a wide variety of applications, including home and commercial lighting, street lighting, automotive lighting, display screens, backlighting for televisions and monitors, and many other areas.
Thanks to their energy efficiency, durability and flexibility, LEDs have revolutionized the lighting industry and have become a popular choice for a variety of lighting applications.
Light color
The term "light color" refers to the perceived color of light emitted by a light source. Light consists of electromagnetic radiation of different wavelengths, and the different wavelengths produce different color perceptions.
The light color is determined by the spectral distribution of the emitted light, i.e. how much light is contained in different wavelength ranges. Light color is often measured using color temperature, which is given in Kelvin (K). Lower color temperatures appear as warm light with a reddish or yellowish tint, while higher color temperatures appear as cool light with a bluish tint.
Here are some typical light colors and their uses:
Warm white: Light with a color temperature of around 2700K to 3000K is called warm white. It creates a cozy, relaxing atmosphere and is often used in living rooms, restaurants or hotels.
Neutral white: Light with a color temperature of around 3500K to 4000K is referred to as neutral white. Appearing as a neutral white light, it is commonly used in offices, schools or other work environments where good visibility and concentration are required.
Cool white: Light with a color temperature of around 5000K to 6500K is called cool white. It produces a bright, cool light and is often used in outdoor areas, hospitals, manufacturing facilities or areas where high brightness and good color rendering are required.
It is important to note that the color of light is not only determined by the color temperature, but also by the spectral composition of the light. Color rendering index (CRI) quality indicates how naturally and accurately a light source renders the colors of illuminated objects. A higher CRI value indicates better color rendering.
Choosing the right light color is important to achieve the desired atmosphere and effect in different application areas. It can also influence personal preferences and the function of the lighted space.
Lumens
Lumen (lm) is a unit of measurement for luminous flux, which is the total amount of light energy emitted by a light source per unit time. It indicates how much visible light is emitted by a light source, regardless of the direction in which the light is emitted.
In other words, the lumen is a measurement of the brightness of a light source. The higher the luminous flux in lumens, the brighter the light source.
The measurement of luminous flux takes into account the sensitivity of the human eye to different wavelengths of visible light. There are curves that represent the sensitivity of the human eye to different colors, and Luminous Flux takes these curves into account to measure brightness in a way that is relevant to the human eye.
The luminous intensity of a light source, i.e. the brightness in a certain direction, is closely related to the luminous flux, but not identical. Luminous intensity is measured in candela (cd) and indicates the brightness in a specific direction.
The lumen measurement is particularly useful to compare the brightness of light sources or to determine the light needs in specific applications. For example, the lumen rating of an incandescent light bulb can help make a decision about whether it is bright enough to illuminate a room. Depending on the application and personal preference, a higher lumen rating may be desired for brighter lighting, while a lower lumen rating may be preferred for dim or atmospheric lighting.
It is important to note that the luminous flux alone does not indicate the quality of the color rendering or the distribution of the light. The color rendering index (CRI) is often used to assess color rendering, and the distribution of light is influenced by the beam angle and the light distribution of the light source.
Luminance
Luminance refers to the brightness or intensity of light emitted or reflected from a surface in a specific direction. It describes how bright a surface appears when illuminated by a light source or when it emits light itself.
Luminance is measured in units of candelas per square meter (cd/m²). It indicates how much light is emitted or reflected per unit area in a specific direction. Higher luminance means a surface appears brighter.
The luminance of a surface depends on various factors, including the properties of the material and the lighting situation. A glossy, reflective surface can have a higher luminance than a matte, absorptive surface because more light is reflected. The color and texture of a surface can also affect luminance.
Luminance is an important concept in display technology, particularly in televisions, monitors and other display devices. High luminance enables better brightness and contrast representation on the screen, resulting in a clearer and more vivid display.
In lighting engineering, luminance can also be used to measure the brightness of light sources or luminaires in specific directions. This can help in lighting planning and measurement to determine the light distribution and desired illuminance in a space.
Luminance is an important consideration when designing lighting systems and evaluating the visual impact of surfaces and display devices. It allows a quantitative description of brightness and helps create a pleasant and functional visual environment.
Luminous intensity
Luminous intensity refers to the amount of light that a light source radiates or emits in a specific direction. It indicates how much light energy is emitted by the light source per solid angle.
Luminous intensity is measured in the unit candela (cd). A candela is equal to the luminous flux (lumen) emitted in a given direction divided by the solid angle in which the light is emitted.
The luminous intensity of a light source should not be confused with brightness or the total amount of light emitted (lumens). Luminous intensity focuses on the direction in which the light is emitted. A light source can have a high luminous intensity, but when the light is spread over a wide solid angle, the brightness can be low. Conversely, a light source can have a low luminous intensity, but when the light is tightly focused, the brightness can be high.
Luminous intensity is important in many applications, particularly lighting design and security. It makes it possible to measure and control the brightness and intensity of light in a specific direction. An example is the use of headlights, where a high luminous intensity is required to create a focused and long-range beam of light.
The luminous intensity of a light source can be influenced by various factors, including the power of the light source, the optics or reflectors that direct or focus the light, and the emission characteristics of the light source itself.
It is important to note that luminous intensity only indicates the intensity of the light emitted in a specific direction and does not say anything about the distribution of the light or the illuminance at a specific point. To measure illuminance, the luminous intensity is used in conjunction with the beam angle and the distance from the light source.
Lux
Lux (lx) is a unit of measurement for illuminance, i.e. the amount of light falling on or hitting a specific surface. It measures the brightness of light per unit area.
Specifically, Lux indicates how many lumens per square meter (lm/m²) fall on or are reflected from a surface. The higher the lux value, the brighter the lighting on the surface.
Illuminance in lux depends both on the luminous intensity of the light source and on the distance to the illuminated surface. As a light source moves farther from the surface, the illuminance decreases as the light is spread over a larger area.
Lux measurement is important in many lighting applications to ensure there is sufficient brightness for specific activities. For example, there are recommended minimum lux levels for different work environments to ensure employee safety and productivity. Lux measurement is also important in areas such as architecture, stage lighting, street lighting and security systems.'
However, it should be noted that lux alone does not make any statement about the quality of the light or the color rendering. Color rendering is often assessed using the color rendering index (CRI), and light color can be specified using color temperature.
Illuminance in lux can be measured using a lux meter or light meter that records the light intensity on a surface.
Reflector
A reflector in lights is used to direct and focus the emitted light and improve the light output. Here are some of the main reasons why reflectors are used in luminaires:
Light control: A reflector makes it possible to direct the light in a specific direction. The shape of the reflector and the positioning of the light source allow the light to be focused and controlled in a targeted manner. This allows efficient lighting to be achieved, with the light being directed exactly where it is needed.
Concentration of light: A reflector can focus the emitted light to produce a higher light intensity in a specific zone. The shape of the reflector focuses the light on a smaller area, resulting in increased brightness. This is particularly useful in applications where high levels of illumination or a strong beam of light are required, such as in spotlights or flashlights.
Improving the luminous efficacy: The luminous efficacy of a light source can be increased by using a reflector. A well-designed reflector can reflect the emitted light and direct it back in the desired direction, rather than losing it or scattering it into unwanted areas. This improves the efficiency of the light source and less energy is wasted.
Reduce Glare: A reflector can also help reduce glare by directing light so it doesn't fall directly into the viewer's eyes. Targeted control of the light distribution allows uniform and comfortable lighting to be created without annoying glare.
It is important to note that the exact effect and function of a reflector depends on various factors such as shape, surface finish and positioning. The use of a reflector can significantly improve the lighting performance and efficiency of a luminaire, helping to meet desired lighting requirements in various applications.
Reflection
Reflection is the process by which light or other electromagnetic waves bounce or reflect off a surface. When light hits a surface, part of it is absorbed while the other part is reflected.
Reflection occurs due to the interaction between the light and the atoms or molecules in the surface. The reflected light rays follow the laws of geometric optics, in particular Snell's law of reflection. This law states that the angle of incidence of the light ray is equal to the angle of reflection, measured to the normal of the surface at the point where the light strikes.
The reflection can have different types of surfaces and effects. Here are some examples:
Regular reflection: With regular reflection, the light rays hit a smooth surface and are reflected in a defined direction. This results in a mirror-like effect where the reflected light is at a certain angle to the plane of incidence.
Diffuse Reflection: In diffuse reflection, light rays strike a rough or irregular surface. The light is scattered and reflected in different directions, resulting in a diffuse light distribution. This effect causes the light to be distributed evenly in all directions, creating diffuse lighting.
Internal Reflection: Internal reflection can occur in certain materials when light reflects off an interface between two materials in such a way that it becomes trapped within a medium. This phenomenon is used in optical fibers and total reflection prisms.
Reflection is of great importance in many fields, such as optics, lighting technology, imaging and communications technology. It affects the visibility of objects, image quality, light distribution and much more. By understanding reflection, we can use light efficiently to design lighting systems, create images, and transmit information.
Reflection degree
Reflectance is a measure of how much light is reflected off a surface. It indicates the ratio of the reflected luminous flux to the incident luminous flux and is expressed as a percentage or as a decimal number.
A reflectance of 100% means that the surface reflects all of the incoming light and absorbs nothing. A perfectly reflective surface would theoretically have 100% reflectance. In practice, however, it is difficult to achieve a fully reflective surface since some light is always absorbed or scattered.
A reflectivity of 0% means that the surface does not reflect any light and absorbs everything. Such a surface appears black because no reflected light comes back.
Most surfaces have a reflectivity somewhere between 0% and 100%, depending on the material properties and surface finish. For example, matte surfaces often have a lower reflectivity because the light is diffused rather than reflected in a specific direction. Shiny or polished surfaces have a higher degree of reflection because the light is reflected in a certain direction.
The degree of reflection plays an important role in lighting technology and lighting planning. It affects the brightness and light distribution of an illuminated environment. When designing lighting systems, it is important to consider the reflectivity of surfaces to achieve the desired lighting effect and minimize unwanted glare or light leakage.
The degree of reflection can be measured using special measuring devices such as a reflectometer or a spectrometer. These devices detect the incident luminous flux and the reflected luminous flux and calculate the reflectance accordingly.
Workplace lighting
Task lighting refers to the targeted lighting in workplaces where specific visual tasks are performed. It is designed to ensure optimal visibility, concentration and comfort for workers, thus improving productivity and well-being at work.
Task lighting is used in a variety of work environments including offices, factories, workshops, laboratories and other work areas where precise or detailed tasks need to be performed. Depending on the type of work, different requirements can be placed on the lighting.
In the case of workplace lighting, lamps or lamps with a narrow beam angle are often used in order to direct the light specifically onto the work area. This allows for improved brightness and contrast perception to see fine detail and minimize eye strain. Individual desk lights, desk lamps or special work lights can be used to adjust the lighting in the workplace.
The illuminance in the workplace lighting is determined in accordance with the applicable standards and guidelines in order to ensure adequate brightness. Light color or color temperature can also be taken into account to optimize visual well-being and color perception.
Designing suitable workplace lighting requires a careful analysis of the work tasks, interior design, ergonomic requirements and other factors. Well-designed task lighting can reduce eye fatigue, decrease error rates, and improve worker health and safety.