We report on solution‐processed, semitransparent organic solar cells that are implemented as lenses in sunglasses. The electrical power provided by the lens‐fitted solar cells sustains a microelectronic circuit that is used to read out temperature and illumination intensity sensors and to make this information available on two displays integrated into the temples of the “Solar Glasses”. The microelectronic circuit is designed to operate at illumination intensities down to 500 lux, rendering the Solar Glasses suitable for outdoor and indoor use as well as for operation in diffuse light. Hence, this case study provides an example for consumer‐oriented mobile applications, self‐powered by integrated solar cells, which specifically exploit the unique properties of organic solar cells.

In this work, the authors present their investigations of the benefits of combining the latest silicon carbide MOSFETs with novel packages for electronic ballasts of inductively coupled plasmas. Such plasmas require MHz inverters with output powers above 2 kW. Additionally, for a breakthrough of the technology efficiencies >90% have to be realised. It has been shown that a combination is achievable with SiC FETs. Nevertheless, even though the transistors have undergone significant development in recent years, one limiting factor has mostly remained untouched. The common TO-247 package does not fit to the requirements of a fast switching application. Within the latest launch of the new generations of SiC MOSFETs, some are available in novel packages with kelvin source connection, like 4pin TO-247 and 7pin D2Pak. The authors compare three versions of the latest generation in a resonant full-bridge inverter and in application-oriented test. Thereby, the 7pin D2Pak and one of the 4pin TO-247 transistors were 65 mΩ devices and the second 4pin TO-247 FET was a 45 mΩ device. For the investigations, the authors made simulations, built three MHz inverters, and conducted measurements. Consequently, efficiencies of 93.9% could be achieved at a switching frequency of 2.5 MHz and an output power of P out =2.6 kW.

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Inductive plasma discharge has been a part of continuous investigations since it was discovered. Especially the E- to H-mode transition and the hysteresis behavior have been topics of research in the last few decades. In this paper, we demonstrate a way to reduce the hysteresis behavior by the usage of a microwave ignition system. With this system, a significant decrease of the needed coil current for the ignition of the inductive driven plasma is realized. For the microwave generation, a magnetron as in a conventional microwave oven is used, which offers a relatively inexpensive way for microwave ignition aid. At the measured pressure of 7.5 Pa, it was possible to reduce the needed coil current for the inductive mode transition by a factor of 3.75 compared to the mode transition current without the ignition aid. This was achieved by initiating the transition by a few seconds of microwave coupling. The performed simulations suggested that the factor can be further increased at higher pressures. That is especially interesting for plasmas that are hard to ignite or for RF-sources that cannot deliver high enough currents or frequencies for the ignition.

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