RESUMO
We present a method for the quantitative determination of the photon force (PF)-the force generated by the radiation pressure of photons reflected from the surface. We propose an experimental setup integrating innovative microelectromechanical system (MEMS) optimized for the detection of photon force (pfMEMS). An active microcantilever was used as the force detector, while the measurement was conducted in a closed-loop setup with electromagnetic force compensation. In opposition to our previous works, this measurement method provides quantitative not qualitative assessment of PF interaction. Final current-balance setup is suitable for light sources from tens of microwatts to few watts. In our article, we present the results of the performed experiments, in which we measured the PF interactions in the range up to 67.5 pN with resolution of 30 fN in the static measurement.
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FótonsRESUMO
In this paper we present the numerical and experimental results of a design optimization of electromagnetic cantilevers. In particular, a cost-effective technique of evolutionary computing enabling the simultaneous minimization of multiple criteria is applied. A set of optimal solutions are subsequently fabricated and measured. The designed cantilevers are fabricated in arrays, which makes the comparison and measurements of the sensor properties reliable. The microfabrication process, based on the silicon on insulator (SOI) technology, is proposed in order to minimize parasitic phenomena and enable efficient electromagnetic actuation. Measurements on the fabricated prototypes assessed the proposed methodological approach.
RESUMO
In the present paper, we describe a high sensitivity intensity fibre-optic displacement sensor with tens of picometre resolution combined with a sub-picometre resolution interferometric calibration system. Both integrated components form the so-called "2 in one ferrule" system 2iOF. The design and construction of the presented device depend on integrating two sensors' systems within one fibre-optic measuring head, which allows performing in situ calibration process with no additional time-consuming adjustment procedure. The resolution of the 2iOF system is 31 pm/Hz1/2 obtained with an interferometric Fabry-Perot based calibration system-providing accuracy better than tens of fm/Hz1/2 within 1 MHz bandwidth in the measurement range of up to 100 µm. The direct response from the intensity sensor is then the 2iOF output one. It is faster and more convenient to analyze in comparison, with much better resolution (3 orders of magnitude higher) but on the other hand also more time consuming and dependent on the absolute sample position interferometer. The proposed system is flexible and open to various applications. We will present the results of the piezoelectrical actuator displacement measurements, which were performed using the developed system.
RESUMO
We report on the design, properties, and applications of a high-resolution and wide-bandwidth light intensity fiber optic displacement sensor for microelectromechanical system (MEMS) metrology. There are two types of structures that the system is dedicated to: vibrating with both high and low frequencies. In order to ensure high-frequency and high-resolution measurements, frequency down mixing and selective signal processing were applied. The obtained effective measuring bandwidth ranges from single hertz to 1 megahertz. The achieved resolution presented here is 116 pm/Hz1/2 and 138 pm/Hz1/2 for low-frequency and high-frequency operation modes, respectively, whereas the measurement of static displacement is 100 µm.