of the future
The eye is our most important sensory organ: Only light creates the conditions for our vision. Our perception can be influenced by certain properties such as the intensity, distribution and colour of light.
You will quickly come across a multitude of technical terms relating to the subject of light. PIXLIP offers a small overview of the most important terms, units and sizes in lighting technology.
The Light density is the measure of the brightness impression made by an illuminated surface. It describes the ratio of light intensity to the size of the illuminated surface: Candela / m².
Special case: Similar to matt surfaces, translucent textiles do not reflect light but transmit it. In this case, luminance is calculated from illuminance (candela) and transmittance. The transmittance describes the ratio of transmitted and incident luminous flux.
The Luminous flux is expressed in Lumen (lm) and describes the total light output of a light source. In contrast to the energy unit Watt, the luminous flux also includes the spectral luminous sensitivity of the eye.
The Light intensity is the luminous flux that leaves the light source in a certain direction. Measured as lumens per solid angle: Candela (cd). As the basic unit of lighting technology, all other lighting parameters are derived from it.
The Luminous efficacy describes the amount of light (Lumen) that is produced per energy input (Watt). It therefore measures the cost-effectiveness and efficiency of the light source. The higher the luminous efficacy, the more energy- and cost-efficient the light source.
The average service life of a lamp is defined as the point in time at which only 50% of the components are functional. A long service life saves investment and maintenance costs. It is given in hours (h).
The lighting intensity (Lux) describes the so-called luminous flux density on a surface and refers to the ratio between the luminous flux (lumen) and the size of the illuminated surface in m² (lm / m²). It can be measured at any point in the room, but decreases with distance from the light source.
Once fiercely criticised as cold, dark and expensive, LEDs are now regarded as the future of lighting technology. We will explain why this is the case, which advantages LEDs bring, and what you should know about the inconspicuous light-emitting diodes.
As a semiconductor diode, the LED (Light Emitting Diode) belongs to the group of electroluminescent lamps. It converts electrical energy into light. As soon as electric current flows through the diode, it emits light. In the past, this technology could only produce blue, green, yellow and red light. LEDs were therefore mainly used as signal light in switches or displays. Only at the end of the 1990s was it possible to produce white light with the aid of an additional fluorescent luminescent layer in the semiconductor crystal. In addition, it is now common to bundle red, blue and green light emitting diodes to obtain the mixed color white. These RGB LEDs enable more than 16 million different light colors.
The development of powerful LED lighting technologies is progressing at a similar pace to that of computer technology. Compared to conventional lighting solutions, LEDs already offer many decisive advantages in the areas of lighting design, economy and sustainability. Architects and lighting designers have recognised this trend too. There is an increasing use of the new LED technology in new buildings and renovations.
While the light bulb was driven out of the market a few years ago, the LED is currently fighting for market leadership. Developers are therefore working in particular on “intelligent lighting management systems” that adapt dynamically to general lighting conditions and people’s biorythmic needs. In addition, more compact designs, better luminous efficacy and cheaper production are the focus of further development.
LEDs offer ideal conditions for a comprehensive and multi-faceted lighting design:
Light quality: LEDs are available in various power classes that differ primarily in the desired brightness level. Thanks to their good colour rendering of Ra95 and a high luminous efficacy of up to 150 lumens/watt, they also meet high demands. The point-shaped light source permits precise light control. With the aid of optics, the light can also be scattered without dazzling. The wide range of colours also makes it possible to create atmospheric and effective lighting situations. With light colours from 2500 K to 6000 K, a variety of white light can also be produced.
Light control: As an electronic component, the LEDs can be precisely controlled and infinitely dimmed so that they can be easily integrated into lighting management systems. For example, the lighting can be activated and dimmed by motion detectors. The delay-free start of the LEDs and the fast response to the control system also enable fast and dynamic lighting scenarios.
LEDs offer a number of economic advantages over conventional light sources.
Long service life: LEDs are considered to be very resistant and robust. They not only withstand rough vibrations, but also extreme temperature fluctuations. Early failures of the technology are the rare exceptions. With lifetimes of over 50,000 hours, an LED is much more durable than other light sources. After this time, on average they still emit about 70% of their original brightness and do not fail immediately. Maintenance costs are therefore almost completely eliminated.
Energy efficiency: Compared to the old light bulb, LEDs consume about 90 percent less electricity. Operating costs can be enormously reduced thanks to the low power consumption. With a luminous efficacy of 110-160 lm/W, they achieve low power consumption.
Rising energy costs and scarce resources are prompting more and more users to switch to energy-efficient solutions such as LED technology.
Light emission: The light spectrum of the LED is only in the visible range. Therefore, there is no dangerous UV and infrared radiation, so that for example plastics do not suffer from the illumination and colours do not fade. Even diurnal animals and insects are spared due to the lack of UV radiation.
Recycling: Unlike energy-saving lamps, LEDs do not contain poisons or harmful substances such as mercury and can therefore be disposed of in an environmentally friendly manner without great effort.
Conserving resources: The low power consumption of the LEDs ensures low CO2 emissions. The consumption of metals such as copper is also reduced.
The human eye does not only distinguish between light and dark. Our perception is also determined by the colour of the light: While warm white light is perceived as cosy, neutral white strikes as rather cool and matter-of-fact.
The eye is our most important sense organ. We receive more than 80% of all information through our eyes: And through light stimuli. Only ambient light makes our daily visual perception possible. This becomes particularly apparent in the dark or with inadequate lighting, when our vision is impaired and our orientation suffers. So while we avoid darkness, we feel attracted to light: an effect that benefits advertising in particular.
The so-called Light color describes the inherent color of the light emitted by a light source. The light colour is measured by the so-called colour temperature in Kelvin (K). As a yardstick for this colour temperature serves the “Planck’s radiator”. This is an idealized black body that does not reflect light but swallows it. If it is heated slowly, it passes through a colour scale from red to yellow, white and light blue. The higher the temperature, the whiter the colour.
The color temperature of white light colors is divided into three main groups:
Warm white with color temperatures below 4000 K. This light color is perceived as cosy and relaxing and resembles the natural light during a sunset.
Neutral white with color temperatures between 4000 and 5000 K. This color creates a rather cool atmosphere and is therefore suitable for kitchens and bathrooms, for example.
Daylight white with color temperatures above 5000 K. This light color corresponds to daylight during lunchtime and has a positive effect on our well-being. It promotes concentration and is ideal for illuminating workplaces.