|
|
A pair of phase-synchronized semiconductor lasers for length metrology
Hucl, Václav ; Holá, Miroslava ; Čížek, Martin ; Řeřucha, Šimon ; Pham, Minh Tuan ; Pravdová, Lenka ; Lazar, Josef ; Číp, Ondřej
Semiconductor lasers are increasingly widespread in areas that have been so far dominated by He-Ne lasers. One of such areas is the length metrology, where He-Ne laser operating at 633nm wavelength is still a traditional source of coherent light for laser interferometers distance measuring. The advantages of semiconductor lasers compared with He-Ne laser are greater optical power and a significantly wider range of wavelength tuning without mode jumps. Another advantage is the possibility of frequency modulation of wavelength of the laser diode by directly changing the injection current. The benefits predetermine these laser diodes for the realization of dual-frequency laser sources for heterodyne interferometry. In this case, using a phase-locked loop technique the optical frequency of a laser diode is locked to the optical frequency of another laser diode with a certain frequency offset in the MHz order. In our contribution we present utilization of DBR laser diodes in implementing a dual-frequency laser source for laser interferometry with heterodyne detection.\n
|
|
|
SMV-2015-21: Optical frequency reference for visible spectral range
Lazar, Josef ; Hrabina, Jan ; Holá, Miroslava ; Oulehla, Jindřich ; Pokorný, Pavel
The content of this contractual research project for the institute of biophysical chemistry was a research and development of an optical frequency reference for the stabilization of a laser for spectroscopy in the visible spectral range. Spectroscopy measurements with a stabilized laser improve significantly the precision of the measurement thanks to direct traceability of the optical frequency to specific transitions in a suitable absorbing media that are listed in the recommendations of the international metrology commission. The reference is represented by a medium of ultrapure vapour of molecular iodine filed into a cell. The optical design of the cell includes windows with antireflexion coatings and a design with multipass arrangement.
|
|
| |
|
|
SMV-2015-34: Development of a new optical method for barrel rifling straightness measurement
Holá, Miroslava ; Řeřucha, Šimon ; Oulehla, Jindřich ; Lazar, Josef
The aim of the project of the contractual research was to establish an optical lab for the measuring of barrel rifling straightness and to perform laboratory measurement of samples of ballistic barrels as well as analyse the measurement data. The used method is based on the laser measuring of straightness where side deviations of a beam are detected. These deviations are caused by deviations of the position of the retroreflector while it is shifted down the measured barrel. This retroreflector copies deviations of a barrel from straightness. The measured data were analysed with the help of our measuring software. The realization of the optical lab continues the previous performed study.
|
|
|
SMV-2015-24: Optical frequency references for laser spectroscopy
Hrabina, Jan ; Holá, Miroslava ; Oulehla, Jindřich ; Pokorný, Pavel ; Lazar, Josef
The contractual project was oriented to development and research of novel types of absorption cells for laser spectroscopy applications – these cells are intended for frequency stabilization of ultra-stable laser standards and investigation of spectral parameters of unknown liquids and gaseous environments. Novel methods for preparation of antireflection coatings on optical windows were investigated due to strict request for minimalization of optical losses and backreflections of interacting laser light at optical windows of the developed cells. Research of methods for thermal protection of the optical windows during the welding process was oriented to unique approach of inert gas jet cooling of AR coatings. Investigation of possibility of AR coatings homogenization was done by method of thermal baking at different temperature levels.
|
|
|
Measurement of real-time gigacycle fatigue through real-time interferometry
Lazar, Josef ; Holá, Miroslava ; Hrabina, Jan ; Číp, Ondřej
We present an interferometric method for measurement of strain induced deformation of metal samples in experiments inducing high-cycle fatigue. The motivation is to get real-time information about the deformation of a metal sample under test, its elongation imposed by fast vibrating actuator. Fatigue of materials is a process of degradation of a material due to repeated application of forces which includes nucleation and propagation of cracks and leads to the failure of the component. It may appear in all parts of machines or structures which rotate, vibrate, are repeatedly loaded, are subjected to temperature gradients etc., so statistically, fatigue is implied in about 80% of all industrial failures.
|
|
|
Coordinate interferometric system for measuring the position of a sample of the electron lithograph
Holá, Miroslava ; Lazar, Josef ; Čížek, Martin ; Řeřucha, Šimon ; Číp, Ondřej
This project is called "Platform of advanced microscopic and spectroscopic techniques for nano and microtechnology." The coordinator of this project is the Brno University of Technology / Faculty of Mechanical Engineering and the co-investigators are ON Semiconductor Czech Republic, Ltd., Optaglio Ltd., Tescan Brno, Ltd. And the Institute of Scientific Instruments of the CAS, v. v. i.. In this project we are working on a design of an interferometric measuring system, laser source and detection techniques for a coordinate measuring system of the table of the electron beam lithography.
|
|
| |
|
| |
|
| |
guest ::
