Technical Notes

Arturo Mediano Y.I.C. Technical Advisor - Professor University of ZaragozaAs you know from some of my previous publications, I love near field probes. They are very useful to "see" magnetic and electric fields in time domain (scope) or frequency domain (scope with FFT or spectrum analyser). When interested in electric fields, a small tip is used to capture electric field...

T.V. Pfeiffer, J. Feng, A. Schmidt-Ott Department of Chemical Engineering, Delft University of Technology, Delft 2628 BL, Netherlands The paper selects a number of recent developments in spark production of nanoparticles that are important for production of nanopowders and nanoparticulate materials. It explains the method, including recent improvements, and refers to theoretical considerations as well as practical experience in controlling...

In optical networks where action on a message or signal is time critical, latency becomes a critical design element. Latency in communications networks is comprised of the networking and processing of messages, as well as the transmission delay through the physical fibre. Measuring and optimising this optical transmission delay can be critical in diagnosing latency issues in a data centre...

FFT Spectrum Analysers, such as the SRS SR760, SR770, SR780 and SR785, take a time varying input signal, like you would see on an oscilloscope trace, and compute its frequency spectrum. Fourier's theorem states that any waveform in the time domain can be represented by the weighted sum of sines and cosines.The FFT spectrum analyser samples the input signal, computes...

Investing in a new scanning electron microscope (SEM) is a strategic move towards enhancing business performance and operational efficiency. Whether you're grappling with the sluggishness of traditional floor models or the prolonged turnaround times of external services, upgrading to a more accessible, faster, and easier-to-operate SEM is essential. Desktop SEMs: Cost-Effective Solutions The decision between a desktop SEM and a...

Scanning electron microscopy (SEM) has become a powerful and versatile tool for material characterisation. This is especially so in recent years, due to the continuous shrinking of the dimension of materials used in various applications.  What is SEM? SEM stands for scanning electron microscope. As the name suggests, electron microscopes use electrons for imaging, in a similar way that light...

Thomas Horseman, Mehdi Tajvidi , Cherif I. K. Diop , Douglas J. Gardner   Lignocellulose nanofibrils (LCNF) were produced from thermo-mechanical pulp (TMP) using a micro-grinder and were characterised with respect to fibre diameter and thermal stability. The initial water content in the TMP affected the defibrillation process and longer grinding time was necessary for the airdried TMP, resulting in...

Acousto-Optic Beam Modulators and Deflectors Control Laser Beams in Many Applications. by John Lekavich, Director, IntraAction Acousto-Optics, the interaction of sound waves and light in a transparent medium, has proven an effective means of amplitude-modulating, deflecting, or shifting the optical frequency of laser light. When a transparent medium is subject to a stress, the optical refractive index of the medium...

An absolute position measurement system has a noise floor of less than 0.02 nm/√Hz over a range of 1.2 mm. Measuring to the nanometer scale is no small feat—getting there takes careful engineering and a fundamentally good sensor. The sensors used for stage position feedback inside semiconductor lithography tools regularly achieve this level of precision. Zygo has supplied displacement measuring...

Stanford Research Systems BGA244 The BGA244 Binary Gas Analyser from Stanford Research Systems (SRS) is a new product harnessing the fundamental physical principles of acoustic resonance to measure the speed of sound in a gas mixture and provide gas ratio measurements with errors as low as 100ppm. This technique has advantages over conventional thermal conductivity binary gas analysers with...