LINEAR LIGHTING

by AREND #2 | Sep 22, 2019 | Blog

ARCHITECTURAL LIGHTING

Architectural lighting is a field within architecture, electrical engineering that is concerned with the design of lighting systems, including natural light, electric light, or both, to serve human needs.

linear LED for architectural lighting from arend:

-SAM LINE:

Luminaire for indoor and outdoor architectural linear lighting, with LEDs color temperature is 3000 – 6000 kelvin and RGB. This material allows the device to be installed. The product is supplied with a cable of L= 80 mm with IP67 male and female connectors fitted with an antidetachment locknut on both ends (not the head). Easy to install and a robust design for difficult environments. 24 Volt DC dimmable driver for dimming. IP65 protection on the product and the continuous line system .
This product can be produced in different lengths.

-NIKI LINEAR:

Luminaire for indoor architectural linear lighting LED color temperature is 3000 – 6000 kelvin and RGB, Flat direct LED with PMMA diffuser and body: extruded anodize aluminum (powder coating an option).IP44 (IP54 only for option). Total power: 12 w/m, 24 Constant voltage dimmable types driver can be used for dimming. Chromaticity tolerance (initial MacAdam: 3). Color rendering Ra> 80.
This product can be produced in different lengths.

-BARRISOL LINEAR:

Luminaire for indoor architectural linear lighting – with warm white LEDs (LED color temperature is 3000 – 6000 kelvin and RGB). A surface LED luminaire, flat direct LED with PMMA diffuser and body: extruded anodize aluminum (Powder coating an option).IP44 (IP54 only for option). For special ceiling. Total power: 12 w/m, constant current outside driver. Chromaticity tolerance (initial MacAdam: 3). Color rendering Ra>80. Plug and play connector to make the installation easy. Luminaires length can be change by project submultiple 28 cm.
This product can be produced in different lengths.
Suitable for barrisol ceiling.

-LIOSA LINEAR:

Luminaire for indoor architectural and pendant linear lighting, a surface LED luminaire, flat direct LED with PS diffuser and body: extruded anodize aluminum (powder coating an option) plug and play connector to make the installation and wiring easy. Class I electrical, IP44 (IP54 only for option). Total power: 20 w/m, slave luminaire for DALI control (an option only) with LED converter. LED color temperature is 3000–6000 kelvin. Chromaticity tolerance (initial MacAdam: 3). Color rendering Ra> 80.
This product can be produced in different lengths.

Arand Lighting Group

Light diffusion curve

by AREND #2 | Aug 31, 2019 | Blog

Light diffusion curve

Light diffusion curve Or light intensity distribution

A curve is used to determine the intensity of light emitted by a light at different angles. Since most light sources are not point-based, so they do not have a constant light intensity in different directions.

In optical computing, it is important to know how light is distributed, so manufacturers of different lamps curve that lamp using measurements.

One of the most common methods for displaying a curve is to use a polar curve, since in many lights the light is symmetrical to the perpendicular axis of the light and only one curve on one of the vertical plates is sufficient to determine the light distribution.

The polar curves are in the form of closed lines around the lights, the distance of this line to the lights being different at any given angle and reflecting the intensity of light at that angle.

The polar curves have two major disadvantages, one being that the optical flux of the different lamps is not comparable, the other being that at angles with severe variations in light intensity, the accuracy of the curve is low.

Two or more curves are used to determine the light emission of lights that are not axially symmetric. If the light is too focused, the rectangular curves instead of the polar curve will use the horizontal axis of the angle, and the vertical axis of light intensity.

Many lamps have the same light intensity curve (their light intensity distribution is the same) with different light fluxes; for all these lamps, only one light-emission curve for the light-3 lumen is plotted to find the true distribution.

Each lamp must multiply the values obtained by the curve in the specific coefficient of that lamp — the coefficient is equal to the lamp’s light-to-lumen ratio of 2 lumens.

Lights are divided according to the light distribution curve
Light may reach the surface in either direct or indirect form (reflection from other surfaces),

thus dividing the light into lights. If all the light from the lower hemisphere is emitted and hits the work surface directly, the light is called “direct light”.

Source: Pars Shahab

Arand Lighting Group

Color Rendering Index

by AREND #2 | Aug 27, 2019 | Blog

Color Rendering Index

Color rendering index , abbreviation of CRI.

The indicator is used to determine the amount of light available to detect colors.

The human eye has grown so large that it can detect different colors of objects using sunlight.

As a result, sunlight is the best indicator for the human eye.

Because it makes it easy for people to recognize natural colors.

Sunlight has a full spectrum of light, so all colors can be seen at different color temperatures under the sun.

While other light sources have different spectra of light, different light spectra can be found by searching for different sources.

Considering what was said above about the suitability of sunlight in human eyes for color recognition.

Light sources are closer to the spectrum of light than natural sunlight.

In this regard, the Color Spectrum Index (CRI) is used to determine the quality of the light source, which ranges from zero to 100.

By this description, the light where color recognition is impossible is zero, and the light that has the best color display has one hundred indicators.

Better optical resolution is directly correlated with higher CRI percentages.
CRI suitable for color resolution is provided for a 1 to 2 percent light source.

There are many reasons today that there is a growing tendency to use LED lamps.

The most important of these are the color indicators in these lamps.

This level of quality is present in LED lamps and the fact is that they do not have infrared and ultraviolet rays.

Valuable benefits such as:
Non-threatening eye and environmental health, providing high quality light and meeting the needs of the human eye in industrial work environments that require high color accuracy and recognition.

The standard of light produced makes it beautiful to use.

Lighting efficiency

by AREND #2 | Jul 22, 2019 | Blog

Lighting efficiency

Lighting efficiency: Artificial light sources are usually evaluated in terms of luminous efficacy of the source, also sometimes called wall-plug efficacy. This is the ratio between the total luminous flux emitted by a device and the total amount of input power (electrical, etc.) it consumes. The luminous efficacy of the source is a measure of the efficiency of the device with the output adjusted to account for the spectral response curve (the luminosity function). When expressed in dimensionless form (for example, as a fraction of the maximum possible luminous efficacy), this value may be called luminous efficiency of a source, overall luminous efficiency or lighting efficiency.

The main difference between the luminous efficacy of radiation and the luminous efficacy of a source is that the latter accounts for input energy that is lost as heat or otherwise exits the source as something other than electromagnetic radiation. Luminous efficacy of radiation is a property of the radiation emitted by a source. Luminous efficacy of a source is a property of the source as a whole.

The following table lists luminous efficacy of a source and efficiency for various light sources. Note that all lamps requiring electrical/electronic ballast are unless noted (see also voltage) listed without losses for that, reducing total efficiency.

Category	Type	Overall luminous efficacy (lm/W)	Overall luminous efficiency
Combustion	Candle	0.3	0.04%
Combustion	Gas mantle	1–2	0.15–0.3%
Incandescent	15, 40, 100W tungsten incandescent (230 V)	8.0, 10.4, 13.8	1.2, 1.5, 2.0%
Incandescent	5, 40, 100W tungsten incandescent (120 V)	5, 12.6, 17.5	0.7, 1.8, 2.6%
Halogen incandescent	100, 200, 500W tungsten halogen (230 V)	16.7, 17.6, 19.8	2.4, 2.6, 2.9%
	2.6W tungsten halogen (5.2 V)	19.2	2.8%
	Halogen-IR (120 V)	17.7–24.5	2.6–3.5%
	Tungsten quartz halogen (12–24 V)	24	3.5%
	Photographic and projection lamps	35	5.1%
Light-emitting diode	LED screw base lamp (120 V)	Up to 102	Up to 14.9%
	11W LED screw base lamp (230V)	138	20.3%
	21.5W LED retrofit for T8 fluorescent tube (230V)	172	25%
	Theoretical limit for a white LED with phosphorescence color mixing	260–300	38.1–43.9%
Arc lamp	Carbon arc lamp	2–7	0.29–1.0%
	Xenon arc lamp	30–50	4.4–7.3%
	Mercury-xenon arc lamp	50–55	7.3–8%
	Ultra-high-pressure (UHP) mercury-vapor arc lamp, free mounted	58–78	8.5–11.4%
	Ultra-high-pressure (UHP) mercury-vapor arc lamp, with reflector for projectors	30–50	4.4–7.3%
Fluorescent	32W T12 tube with magnetic ballast	60	9%
	9–32W compact fluorescent (with ballast)	46–75	8–11.45%
	T8 tube with electronic ballast	80–100	12–15%
	PL-S 11W U-tube, excluding ballast loss	82	12%
	T5 tube	70–104.2	10–15.63%
	70–150W inductively-coupled electrodeless lighting system	71–84	10–12%
Gas discharge	1400W sulfur lamp	100	15%
	Metal halide lamp	65–115	9.5–17%
	High-pressure sodium lamp	85–150	12–22%
	Low-pressure sodium lamp	100–200	15–29%
	Plasma display panel	2–10	0.3–1.5%
Cathodoluminescence	Electron stimulated luminescence	30	5%
Ideal sources	Truncated 5800 K black-body	251	37%
Ideal sources	Green light at 540 THz (maximum possible luminous efficacy by definition)	683	100%

Sources that depend on thermal emission from a solid filament, such as incandescent light bulbs, tend to have low overall efficacy because, as explained by Donald L. Klipstein, “An ideal thermal radiator produces visible light most efficiently at temperatures around 6300 °C (6600 K or 11,500 °F). Even at this high temperature, a lot of the radiation is either infrared or ultraviolet, and the theoretical luminous [efficacy] is 95 lumens per watt. No substance is solid and usable as a light bulb filament at temperatures anywhere close to this. The surface of the sun is not quite that hot. At temperatures where the tungsten filament of an ordinary light bulb remains solid (below 3683 kelvin).

SI photometry units


Quantity		Unit		Dimension	Notes
Name	Symbol	Name	Symbol	Symbol	Notes
Luminous energy	Q_v	lumen second	lm⋅s	T⋅J	The lumen second is sometimes called the talbot.
Luminous flux, luminous power	Φ_v	lumen (= candela steradians)	lm (= cd⋅sr)	J	Luminous energy per unit time
Luminous intensity	I_v	candela (= lumen per steradian)	cd (= lm/sr)	J	Luminous flux per unit solid angle
Luminance	L_v	candela per square metre	cd/m²	L⁻²⋅J	Luminous flux per unit solid angle per unit projected source area. The candela per square metre is sometimes called the nit.
Illuminance	E_v	lux (= lumen per square metre)	lx (= lm/m²)	L⁻²⋅J	Luminous flux incident on a surface
Luminous exitance, luminous emittance	M_v	lux	lx	L⁻²⋅J	Luminous flux emitted from a surface
Luminous exposure	H_v	lux second	lx⋅s	L⁻²⋅T⋅J	Time-integrated illuminance
Luminous energy density	ω_v	lumen second per cubic metre	lm⋅s/m³	L⁻³⋅T⋅J
Luminous efficiency (of radiation)	K	lumen per watt	lm/W	M⁻¹⋅L⁻²⋅T³⋅J	Ratio of luminous flux to radiant flux
Luminous efficiency (of a source)	η	lumen per watt	lm/W	M⁻¹⋅L⁻²⋅T³⋅J	Ratio of luminous flux to power consumption
Luminous efficiency, luminous coefficient	V			1	Luminous efficacy normalized by the maximum possible efficacy

arend

Illuminance

by AREND #2 | Jul 9, 2019 | Blog

Illuminance

In photometry, illuminance is the total luminous flux incident on a surface, per unit area. It is a measure of how much the incident light illuminates the surface, wavelength-weighted by the luminosity function to correlate with human brightness perception. Similarly, luminous emittance is the luminous flux per unit area emitted from a surface. Luminous emittance is also known as luminous exitance.

In SI derived units these are measured in lux (lx), or equivalently in lumens per square metre (cd·sr·m⁻²). In the CGS system, the unit of illuminance is the phot, which is equal to 10000 lux. The foot-candle is a non-metric unit of illuminance that is used in photography.

Illuminance was formerly often called brightness, but this leads to confusion with other uses of the word, such as to mean luminance. “Brightness” should never be used for quantitative description, but only for nonquantitative references to physiological sensations and perceptions of light.

The human eye is capable of seeing somewhat more than a 2 trillion-fold range: The presence of white objects is somewhat discernible under starlight, at 5×10⁻⁵ lux, while at the bright end, it is possible to read large text at 10⁸ lux, or about 1000 times that of direct sunlight, although this can be very uncomfortable and cause long-lasting afterimages

Common illuminance levels

A lux meter for measuring illuminances in work environments

Lighting condition	Foot-candles	Lux
Full daylight	1,000	10,000
Overcast day	100	1,000
Very dark day	10	100
Twilight	1	10
Deep twilight	0.1	1
Full moon	0.01	0.1
Quarter moon	0.001	0.01
Starlight	0.0001	0.001

Astronomy

In astronomy, the illuminance stars cast on the Earth’s atmosphere is used as a measure of their brightness. The usual units are apparent magnitudes in the visible band. V-magnitudes can be converted to lux using the formula

E_{\mathrm {v} }=10^{(-14.18-M_{\mathrm {v} })/2.5}

where E_v is the illuminance in lux, and M_v is the apparent magnitude. The reverse conversion is

M_{\mathrm {v} }=-14.18-2.5\log(E_{\mathrm {v} })

SI photometry quantities
Quantity		Unit		Dimension	Notes
Name	Symbol	Name	Symbol	Symbol	Notes
Luminous energy	Q_v	lumen second	lm⋅s	T⋅J	The lumen second is sometimes called the talbot.
Luminous flux, luminous power	Φ_v	lumen (= candela steradians)	lm (= cd⋅sr)	J	Luminous energy per unit time
Luminous intensity	I_v	candela (= lumen per steradian)	cd (= lm/sr)	J	Luminous flux per unit solid angle
Luminance	L_v	candela per square metre	cd/m²	L⁻²⋅J	Luminous flux per unit solid angle per unit projected source area. The candela per square metre is sometimes called the nit.
Illuminance	E_v	lux (= lumen per square metre)	lx (= lm/m²)	L⁻²⋅J	Luminous flux incident on a surface
Luminous exitance, luminous emittance	M_v	lux	lx	L⁻²⋅J	Luminous flux emitted from a surface
Luminous exposure	H_v	lux second	lx⋅s	L⁻²⋅T⋅J	Time-integrated illuminance
Luminous energy density	ω_v	lumen second per cubic metre	lm⋅s/m³	L⁻³⋅T⋅J
Luminous efficacy	η	lumen per watt	lm/W	M⁻¹⋅L⁻²⋅T³⋅J	Ratio of luminous flux to radiant flux or power consumption, depending on context
Luminous efficiency, luminous coefficient	V			1	Luminous efficacy normalized by the maximum possible efficacy
Arend

Guide: Where to use LED?

by AREND #2 | Jun 10, 2019 | Blog

Where to use LED?

Guide Where to use LED

Guide Where to use LED? Do you intend to learn more about where to apply LED, or are you in doubt whether or not LED lighting should be part of your next project? This blog focuses on a number of applications, where LED lighting can be implemented with advantage.

LED lighting comes in many different sizes, shapes, and colours, wherefore the market can be seen as a jungle. Some types of LED are waterproof and can be employed outside. Other types are designed to resist vandalism, while some LED units aim to provide a cosy and pleasant lighting. The list is infinite and therefore, it is important that you choose the right lighting solution for your project. Consequently, we intend to provide an overview of some of the possible LED applications.

Building projects

If you are in charge of a construction project, you must consider a LED solution. There exist multiple opportunities and with LED, we can tailor a solution to fit to your exact needs. If you for example need linear LED lighting for a corridor, we can customize the length of the luminaire. This means that you will have one luminous LED tube instead of several luminaires combined together. From this, you prevent so-called dark spots and hereby, you will feel that the lighting is comfortable and more exclusive. Apart from that, several of our luminaires come with a sensor, which regulates the light depending on the activity in the room. This can be efficient in a corridor, where the activity level primarily is concentrated around rush hours. For this reason, you can save a great deal of the energy consumption by implementing LED in your building project.

Parking garages

If the lighting system in the parking garage face an overhaul, you can consider LED as well. The greatest advantage associated with applying LED in parking garages and in similar large areas is the possibility to control the light. By reducing light efficiency when no activity is registered, you will expand the life time of the LED bulbs, which can safe you up to 70% on electricity.

Outdoor spaces

You have numerous opportunities when it comes to outdoor LED lighting. However, not all LED types are suitable for outdoor use. First of all, you must look at the luminaire’s IP code. This code indicates to what extent the luminaire is tolerant towards water and dust. If the luminaire merely has to be able to handle rainwater from above, you will be satisfied with IP23. But if you need a luminaire more resistant towards water and dust, you must look for luminaires with a classification between IP41 and IP68 depending on your needs.

AREND

« Older Entries

Next Entries »