Sensor+Test 2018

••• 11 ••• Innovationen In-situ monitoring Novel “Smart Mirror” laser power meter A group of researchers from National Institute of Standards and Technology (NIST) in Boulder, Colorado, USA, have de- veloped a compact, high-accuracy, point- of-use high-power laser power meter in the form of a folding mirror called “Smart Mir- ror,” making in-situ, real-time measurement of laser power possible. The novel design uses a capacitor-based force transducer and merges optical ele- ments, namely a high reflectivity mirror, and sensing elements into a compact cube package. The four-centimeter-on-a-side cubes can be conveniently embedded into laser optical systems or laser-welding sys- tems for point-of-use, real-time laser power measurement and calibration. “Measuring laser power by measuring the pressure of a laser beam hitting a mirror is a very unique technique, and so far it is the only laser power measurement technique that is truly an in-situ process,” said Alex- andera B. Artusio-Glimpse, a scientist of NIST in Boulder, Colorado, and the primary author. “Unlike any other optical power measurement techniques, our method allows us to continue using the laser for work while a measurement is being taken.” Artusio-Glimpse explained that traditional high-power meters measure laser power by absorbing all the energy of a laser beam as heat and measuring the temperature change. The calorimetric measurement has to temporarily stop the laser beam from work for around tens of minutes. “Using our ‘Smart Mirror’ laser power me- ter, that stop-measure-continue process is no longer needed. Manufacturers can measure the laser power continuously dur- ing every weld and monitor the laser cali- bration in real time, they would know right away whenever the laser has a problem and wouldn’t risk wasting metal parts with bad welds,” Artusio-Glimpse said. The Smart Mirror laser power meter is also referred to as a radiation pressure power meter (RPPM), as the operating principle of this meter is based on measuring the pres- sure of the laser, the radiation pressure. Light has no mass, but it has momentum and when a laser beam strikes an object such as a mirror, it will exert a tiny force known as the radiation pressure on the mirror, which directly relates to the laser power. Delta-R GmbH Halle: 1 • Stand: 162 Digmesa AG Halle: 1 • Stand: 216 Kistler Instrumente GmbH Halle: 1 • Stand: 411 LESCATE SAS Halle: 5 • Stand: 432 LumaSense Technologies GmbH Halle: 5 • Stand: 305 Porex Technologies GmbH, Filtration Group Halle: 1 • Stand: 518 Soundtec GmbH Halle: 1 • Stand: 553 SST Sensing Ltd Halle: 1 • Stand: 513 UNITRONIC GmbH Halle: 1 • Stand: 559 Messetelegramm Anzeige Verlag: CONNEX Print & Multimedia AG Große Packhofstraße 27/28 • 30159 Hannover Telefon: +49 511 830936 Telefax: +49 511 56364608 E-Mail: Internet: Auflage IVW-geprüft. Auflagengruppe: D Redaktion: Martin Braun Verantwortlich für den Anzeigenteil: Tina Wedekind Druck: Druckzentrum Neckar-Alb • 72764 Reutlingen Impressum SENSOR+TEST 2018 MESSEJOURNAL DIE MESSE HALLE 1 STAND 216 DIGMESA - THE LIQUID FLOW SENSING SOLUTION 35 YEARS SWISS & ORIGINAL