Diploma and Master Theses (authored and supervised):
"Die technischen und gestalterischen Möglichkeiten neuer Leuchtmitteltechnologien in der Architektur am Beispiel der LEDä-Technologie";
Supervisor: A. Mahdavi;
Institut für Architekturwissenschaften, Abteilung Bauphysik und Bauökologie,
Light sources are defined according to the process light is generated. The major
types are thermal radiators and discharge lamps. Another group is identified in
light-emitting diodes (LEDs).
A light-emitting diode is a special type of the semiconductor diode, it emits light
when electrically charged. The colour of the emitted light depends on the
composition of the material used as semiconductor crystal.
LEDs have been developed during the last 40 years from glowing indicator
lamps to an acceptable light source for general lighting. Along this way, a
range of developments have taken place, that enabled introduction of LEDs
into certain lighting market segments. Based on research in the 1990s the InGaN
LED technology was discovered. It led to the extensive commercialization of
blue and green solid-state sources, as well as the development of white LEDs.
With a full range of colours, light-emitting diodes quickly began to displace
conventional lamps in many colour-related lighting applications.
Light-emitting diode systems are ideally suited for digital control, which means
they can be dimmed, and a dynamic mix of colours is possible. Depending on
the colour, the efficacy approaches 20-40 lm*w-1, (which corresponds to
halogen lamps). LEDs can last between 25.000 and 50.000 hours and they have
a very moderate power consumption. Therefore the energy and maintenance
savings, justify the higher initial cost.
Today the use of light-emitting diodes is widespread and growing, LEDs are
increasingly being used for illumination applications. Their main applications, in
use as light source, are shops, museums and table lamps.
LED-manufacturers are now concentrating on moving product development
forward and are challenged with meeting and further exceeding the
performance of conventional light sources. To expand acceptance as a light
source for general lighting, LED-lighting must be able to economically and
reliably deliver illumination levels of the present related white light sources.
The aim of this diploma thesis was to explore the present possibilities of use of the
LED-light source and give an outlook of the possible potential in general lighting.
In conclusion can be said, that light-emitting diodes could change the lighting
industry in future, if necessary requirements are met. In architectural planning
LEDs offer a contemporary independence and resulting innovative structures.
The light-emitting diode might create entirely new uses in illumination, never
LED, Architecture, Light
Created from the Publication Database of the Vienna University of Technology.