LED-based photocatalytic reactor design

As a promising technology, photocatalysis shows its unique advantages and potential in many disciplines, from hydrogen production, indoor and outdoor air purification, remediation of non-biodegradable molecular in the factory, to the organic synthesis with high selectivity. In recent years, photocatalytic semiconductor process has shown a high...

Progress in Understanding Color Maintenance in Solid-State Lighting Systems

In this paper, progresses of color maintenance, also known as color shift, in solid-state lighting (SSL) systems are thoroughly reviewed. First, color shift is introduced and a few examples are given from different real-life industrial conditions. Different degradation mechanisms in different parts of the system are also explained. Different...

Thermal management of solid state lighting module

Solid-State Lighting (SSL), powered by Light-Emitting Diodes (LEDs), is an energy-efficient technology for lighting systems. In contrast to incandescent lights which obtain high efficiency at high temperatures, the highest efficiency of LEDs is reached at low temperatures. The thermal management in LED product is then a key design parameter as...

Integrated Automotive High-Power LED-Lighting Systems in 3D-MID Technology

The growing energy consumption of lighting as well as rising luminous efficacies and -fluxes of high-power Light Emitting Diodes (LEDs) have contributed to the widespread use of LEDs in modern lighting systems. One of the most prominent users of the LED-technology is automotive (exterior) lighting. It benefits from LEDs’ high efficiencies and...

Efficiency enhancement calculations of state-of-the-art solar cells by luminescent layers with spectral shifting, quantum cutting, and quantum tripling function

Solar cells of which the efficiency is not limited by the Shockley-Queisser limit can be obtained by integrating a luminescent spectral conversion layer into the cell structure. We have calculated the maximum efficiency of state-of-the-art c-Si, pc-Si, a-Si, CdTe, GaAs, CIS, CIGS, CGS, GaSb, and Ge solar cells with and without an integrated...

Self-healing short-circuits in organic light-emitting diodes and solar cells

Organic materials open the way for large-scale applications of Organic Light-Emitting Diodes (OLED) and solar cells (OPV). These materials can be large-scale processed using printing and coating on rigid and flexible substrates. The resulting devices can therefore be fabricated at low cost for various applications. Production yields suffer,...

Strategy for sustainable OLED textile development, demonstrated through applicable concepts

This graduation project has been executed in cooperation with Philips Research and Holst Centre, within the Platform for Large Area Conformable Electronics by InTegration (PLACE-it) project. The scope of the project is to identify required developments for OLED textile, to fulfill the needs of future users and minimise the environmental impact....

Light-Emitting Diode Junction-Temperature Sensing using Various Voltage/Current Measurement Techniques

Given the temperature dependence of various aspects of light-emitting diode (LED) performance, LED temperature sensing is becoming increasingly important in solid-state lighting applications. This thesis presents an electrical technique for junction-temperature sensing based on the measurement of the forward voltage and current of an LED at two...

Self-healing approach for enhanced reliability of light emitting diodes (poster abstract)

System innovation for sustainable built environments: The case of light emitting diodes

The United Kingdom (UK) government policy is increasingly directed at transforming the built environment to an environmentally sustainable one. The government, for example, has set a target for a reduction in carbon emissions by 80% by 2050 compared to 1990 levels. A large number of new policies and regulations are being introduced to minimise...

Automatic diagnosis and control of distributed solid state lighting systems

This paper describes a new design concept of automatically diagnosing and compensating LED degradations in distributed solid state lighting (SSL) systems. A failed LED may significantly reduce the overall illumination level, and destroy the uniform illumination distribution achieved by a nominal system. To our knowledge, an automatic scheme to...

OLED Display with Single Grain Si TFT. (SG-TFT)

OLED is a current based device, which emitted amount of light depends on the current supplied to the device so steady current flow is needed. In Active Matrix Organic Light Emitting Diode (AMOLED) Display. TFTs are used as driving transistors for OLED. Because of the non uniformity of the TFTs, variation in threshold voltage and mobility has a...

Efficient optimization method for the light extraction from periodically modulated LEDs using reciprocity

The incoherent emission of periodically structured Light Emitting Diodes (LEDs) can be computed at relatively low computational cost by applying the reciprocity method. We show that by another application of the reciprocity principle, the structure of the LED can be optimized to obtain a high emission. We demonstrate the method by optimizing one...

LEDs for fluorescence microscopy

Traditional light sources for fluorescence microscopy have been mercury lamps, xenon lamps, and lasers. These sources have been essential in the development of fluorescence microscopy but each can have serious disadvantages: lack of near monochromaticity, heat generation, cost, lifetime of the light source, and possible distortions due to...

Het gebruik van glasvezels in de vliegtuiginstrumentatie

Fiber optics, a rapidly advancing new technology, seems very well suited for use as data transmission medium in aircraft. The advantages are substantial: galvanic isolation, electromagnetic compatibility, savings in volume and weight, and superior transmission qualities. In this report possibilities and limitations are discussed for using...