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Increased electrical power generated from a thin-film silicon (TF-Si) photovoltaic device can lead to a reduced cost of electricity production that will support the mass adoption of this technology as a renewable energy source. Extracting the highest conversion efficiency from ‘champion’ large area TF-Si modules has been the focus of development at TEL Solar AG, Trubbach. The layer deposition process adjustments and further module technology improvements that led to a significant increase in the absolute stabilized module conversion efficiency of large area (1.43 m 2 ) tandem MICROMORPH™ modules centered first on obtaining high quality amorphous TF-Si deposited materials for the top cell. This was integrated with microcrystalline TF-Si material for the bottom cell that was deposited under conditions close to the transition point between the amorphous and microcrystalline growth regimes. In an optimized solar cell design the TF-Si materials were then combined with effective light management technologies and an improved module layout. The end result of a world record large area (1.43 m 2 ) stabilized module conversion efficiency of 12.34% was certified by the European Solar Test Installation (ESTI). The main technology contributions in the device design for this breakthrough result that generated more than 13.2% stabilized efficiency from each equivalent 1 cm 2 of the active area of the full module are described.

The scientific objective of the X-ray Advanced Concepts Testbed (XACT) is to measure the X-ray polarization properties of the Crab Nebula, the Crab pulsar, and the accreting binary Her X-1. Polarimetry is a powerful tool for astrophysical investigation that has yet to be exploited in the X-ray band, where it promises unique insights into neutron stars, black holes, and other extreme-physics environments. With powerful new enabling technologies, XACT will demonstrate X-ray polarimetry as a practical and flight-ready astronomical technique. Additional technologies that XACT will bring to flight readiness will also provide new X-ray optics and calibration capabilities for NASA missions that pursue space-based X-ray spectroscopy, timing, and photometry.

We successfully produced Resistive-Electrode GEM (RE-GEM) that was applied Resistive-Kapton to electrodes. We measured the gain curve of RE-GEM using an 55Fe radioactive source in the gas mixture of Ar 70 % and CO 2 30 %. We obtained the maximum gain of about 300 at an applied voltage of 740 V.

The Gravity and Extreme Magnetism Small Explorer (GEMS) is an astrophysical observatory dedicated to X-ray polarimetry (2-10 keV) and is being developed for launch in 2014. To maximize the polarization sensitivity of the observatory, GEMS uses polarimeters based on the photoelectric effect with a gas micropattern time projection chamber (TPC). We describe the TPC polarimeter concept and the details of the GEMS implementation, including factors that affect the ultimate polarization sensitivity, including quantum efficiency, modulation factor, systematic errors, and background.

The Gas Electron Multiplier (GEM) is a new device that amplifies an input electron cloud, while keeping its shape unchanged [1]. We have developed various type GEMs using a laser etching technique. Those GEMs had different geometry (pitch, hole diameter and thickness) and materials (polyimide; PI or liquid crystal polymer; LCP). We have applied the GEMs to a photoelectric polarimeter that measures polarization of X-rays emitted from stellar objects. To obtain the polarization accurately, it is necessary for GEMs to have good uniformity in two-dimension. As a result of gain mapping, the standard deviation of gain variation of our standard GEM was ∼ 5%. Our GEMs showed enough uniformity to detect X-ray polarization. Comparing hole diameter and gain maps of the same region, there was no correlation between these two maps. Comparing maps of different type GEMs, there was no difference among them and PI GEMs were more uniform than LCP ones.

We have produced thick-foil and fine-pitch gas electron multipliers (GEMs) using a laser etching technique. To improve production yield we have employed a new material, Liquid Crystal Polymer, instead of polyimide as an insulator layer. The effective gain of the thick-foil GEM with a hole pitch of 140 um, a hole diameter of 70 um, and a thickness of 100 um reached a value of 10^4 at an applied voltage of 720 V. The measured effective gain of the thick-foil and fine-pitch GEM (80 um pitch, 40 um diameter, and 100 um thick) was similar to that of the thick-foil GEM. The gain stability was measured for the thick-foil and fine-pitch GEM, showing no significant increase or decrease as a function of elapsed time from applying the high voltage. The gain stability over 3 h of operation was about 0.5%. Gain mapping across the GEM showed a good uniformity with a standard deviation of about 4%. The distribution of hole diameters across the GEM was homogeneous with a standard deviation of about 3%. There was no clear correlation between the gain and hole diameter maps., Comment: 21 pages, 9 figures

A gas electron multiplier (GEM) is a key device for the photoelectric X-ray polarimeters, which will be launched in the near future. Our GEMs have spatial resolution enough for tracking of photoelectrons and low risk of discharge. GEMs need to perform well in all sorts of tolerance tests for space missions before launch. As a result of gain stability test after switching ON/OFF 6500 times repeatedly, our GEM gain variation is within ±2%. This repetition time scale corresponds to 2-year space mission in the Low Earth Orbit. As a result of charged particle (Fe) irradiation to GEM, our GEM survived more than 500 seconds of Fe ion irradiation (flux is 130 cts/cm2/s). This corresponds to 40-year irradiation in space. Thus, we conclude that our GEMs are stable enough for space missions and tolerance against discharge which is caused by charged particles.

Anti-reflection coating (ARC) is well known as an important technique to enhance solar cell performance. Typical ARC has been applied on the glass surface to reduce light reflection loss at the air/glass interface. However, reflection loss occurs not only at glass surface but also at other interfaces such as glass/transparent conductive oxide (TCO) interface. The refractive index of SiNx is tunable from 1.6 to 2.7, and the range from 1.7 to 2.0 is suitable for ARC at glass/TCO interface. In this study, we examined the AR effect of silicon nitride (SiNx) deposited by plasma enhanced chemical vapor deposition at the glass/TCO interface with thin film silicon solar cell and module. Reflectivity reduction of 1.6% for glass/ZnO substrate has been obtained with optimal SiNx layer, which contribute 2.0% gain in cell efficiency. Besides, we also confirmed the relative efficiency gain of around 2% for large-sized solar module, leading to a world-record large area stabilized module conversion efficiency of 12.34%.

Cm-level high accuracy real-time GPS positioning system is realized nation wide in Japan based on networked Real Time Kinematics GPS (RTK-GPS), and has been commercially operated by Mitsubishi Electric Co. named PAStrade, Positioning Augmentation Services, since September 2003. Also we have recently devised more convenient method at submeter or decimeter accuracy using low cost and compact code-ranging GPS receiver utilizing correction data fed from PAS system. Both of these methods will reduce time and cost significantly to produce precise satellite imagery based on Ground Control Point (GCP), as well as to update maps in geo-centric coordinate, which is necessary to use satellite imagery operationally with GPS

The premises cordless telephone (PCT) system provides a full function access to PSTN (public switched telephone network) subscriber lines via an existing PBX (private branch exchange) and/or a single controller or a network of controllers. The system enhances corporate communications by giving callers direct dial-through access to executives on the move and engineers and technicians working out of reach of wired telephones. The system offers similar benefits for offices, hotels, hospitals, building maintenance services, department stores, shopping malls, trade fairs, etc. Base stations configure the microcell structures with location registration and handoff features which will enable system planners to tailor the system economically to the diverse needs of traffic density and to eliminate the shadowing effects of building structures, walls, etc. The system features are described, including uses of the dynamic frequency assignment and flexible base station arrangement (irregularly located) within a microcell (or picocell) structure to ensure user-friendly operations, full extension of system flexibility, and significant increase in the traffic capacity within a highly dense traffic area. >

We successfully produced Resistive-Electrode Gas Electron Multiplier (RE-GEM) which has resistive electrodes instead of the metal ones which are employed for the standard GEM foils. RE-GEM has a resistive electrode of 25 micron-thick and an insulator layer of 100 micron-thick. The hole structure of RE-GEM is a single conical with the wider and narrower hole diameters of 80 micron and 60 micron, respectively. A hole pitch of RE-GEM is 140 micron. We obtained the maximum gain of about 600 and the typical energy resolution of about 20% (FWHM) at an applied voltage between the resistive electrodes of 620 V, using a collimated 8 keV X-rays from a generator in a gas mixture of 70% Ar and 30% CO2 by volume at the atmospheric pressure. We measured the effective gain as a function of the electric field of the drift region and obtained the maximum gain at an drift field of 0.5 kV/cm.

We have performed a systematic investigation of the gain properties of the GEM foil made from copper-clad liquid crystal polymer insulator (LCP-GEM), which will be used for a satellite mission. We have measured the gain curve of LCP-GEM in pure DME at 190 Torr, and achieved a gain of 3 × 104 at an applied high voltage of 605 V between the LCP-GEM electrodes with a thickness of 100 μm. The charge sharing between the GEM electrodes and readout pad were measured as a function of drift (Ed) or induction (Ei) field. We found that the parallel plate multiplication occurred between the bottom electrode of LCP-GEM and the readout pad above Ei = 6 kV, and the amount of charge collected in each electrode was almost constant with Ed. We investigated the signal shape obtained in each electrode and found that the rise time of signals was explained as induced charge by moving ions and electrons.