Zbigniew Opilski

Technology of ion exchange in glass and its application in waveguide planar sensors

The possibilities of producing waveguide structures in glass using the ion-exchange technique are discussed. The modeling of par- ticular sequences of the technological process with respect to planar and strip waveguide structures as well as refraction profile measurement re- sults for these waveguides are presented. An exemplary application of this technique in the construction of planar sensors is also presented.

Examination of thin films of phthalocyanines in plasmon system for application in NO2 sensors

Surface plasmon resonance spectroscopy is an optical technique that is capable of monitoring chemical and physical processes. It is sensitive to small changes of dielectric properties near a metal surface, and has been used to characterize a number of different types of films. This work analyzes the possibility of using the surface plasmon resonance phenomena for gas detection. We present examinations of thin films of phthalocyanines in plasmon systems from the point of view of their application in NO 2 sensors.

Evaluation of physicochemical properties of SiO2-coated stainless steel after sterilization.

The study of most of the literature devoted to the use of coronary stents indicates that their efficiency is determined by the physicochemical properties of the implant surface. Therefore, the authors of this study suggested conditions for the formation of SiO2 layers obtained with the use of sol-gel methodology showing physicochemical properties adequate to the specific conditions of the cardio-vascular system. Previous experience of authors helped them much to optimize the coating of 316LVM steel surface with SiO2. The values of parameters that determine the usefulness of the coating in medical applications have been determined. In order to identify the phenomena taking place at the boundary of phases and to evaluate the usefulness of the proposed surface modification, taking into consideration the medical sterilization (steam or ethylene oxide (EO)), the potentiodynamic, impedance, adhesion, surface morphology and biological assessment characterizations were performed. Regardless of the usage of the sterilizing agent (steam, EO) the study showed the reduction of critical force causing layers delamination. The research results of corrosion resistance study also confirmed a slight decrease of SiO2 barrier properties of the samples after sterilization in contact with the artificial plasma. SiO2 layers after the sterilization process did not show significant features of cytotoxicity and had no negative influence on blood cell counts, which confirmed the results of quantitative and qualitative studies.

Acoustic system for the estimation of the temporary blood chamber volume of the POLVAD heart supporting prosthesis.

BackgroundThe paper presents a newly researched acoustic system for blood volume measurements for the developed family of Polish ventricular assist devices. The pneumatic heart-supporting devices are still the preferred solution in some cases, and monitoring of their operation, especially the temporary blood volume, is yet to be solved.MethodsThe prototype of the POLVAD-EXT prosthesis developed by the Foundation of Cardiac Surgery Development, Zabrze, Poland, is equipped with the newly researched acoustic blood volume measurement system based on the principle of Helmholtz’s acoustic resonance. The results of static volume measurements acquired using the acoustic sensor were verified by measuring the volume of the liquid filling the prosthesis. Dynamic measurements were conducted on the hybrid model of the human cardiovascular system at the Foundation, with the Transonic T410 (11PLX transducer - 5% uncertainty) ultrasound flow rate sensor, used as the reference.ResultsThe statistical analysis of a series of static tests have proved that the sensor solution provides blood volume measurement results with uncertainties (understood as a standard mean deviation) of less than 10%. Dynamic tests show a high correlation between the results of the acoustic system and those obtained by flow rate measurements using an ultrasound transit time type sensor.ConclusionsThe results show that noninvasive, online temporary blood volume measurements in the POLVAD-EXT prosthesis, making use of the newly developed acoustic system, provides accurate static and dynamic measurements results. Conducted research provides the preliminary view on the possibility of reducing the additional sensor chamber volume in future.

Influence of the refractive profile of a waveguide on the sensitivity of a planar difference interferometer

The work presents the possibility to control the changes involving the difference of the propagation of waveguide modes TE0, TM0, TM1 by respective selection of technological parameters while producing the optics channel of the planar interferometer by ion-exchange technique in glass. The influence of the refractive profile of waveguide structure on the sensitivity of interferometer was observed.

Integrated optical difference interferometer

The present paper discusses theoretical and experimental research on the planar difference interferometer produced with the use of planar technique on a glass substrate plate (planar interferometers) in view of its application in the system of phase-polarization sensors of basic physical quantities.

The novel approach to the estimation of the blood volume in the POLVAD prosthesis

The cardiovascular diseases are common among human population. The patients suffering from heart related disease can be divided into two main groups: pharmacologically cured and the group needing the surgical procedure. In some cases the special type of devices can be used for supporting the heart muscle by pumping the blood along with the heart. In Poland the solution Developed by the Foundation of Cardiac Surgery Development - Polish Heart Assist Device (POLVAD) is used. The prosthesis itself is a pneumatic pulsatile-type extracorporeal device. The temporary blood volume measurement is essential for the automation of the heart supporting process. The most important requirement is the noninvasiveness of the measurements. The new measurement method for the temporary blood volume estimation was suggested and developed by the Department of the Optoelectronics at the Silesian University of Technology and presented in the paper.

Determination of the optical parameters of thin palladium layers and their application in optical hydrogen sensors

The paper presents the results and way of measuring the dispersion of the complex refractive index of thin palladium layers in an atmosphere containing hydrogen with a concentration below the threshold of explosion (<4%). The measurements were carried out making use of exciting the surface plasmon wave.

Spectroscopic ellipsometry measurements and nanocharacterization of conductive graft copolymer thin films

This work presents an investigation on the influence of different factors on conductive graft comb copolymer polymethylsiloxane (PMS) with poly(3-hexyltiophene) (P3HT) and poly(ethylene) glycol (PEG) or dodec-1-en as functional side groups grafted on poly(methylhydrosiloxane) backbone. The analysed factors that influenced the parameters of the layers were temperature and different gas atmosphere (N2, NO2). Samples were measured by spectroscopic ellipsometry under the influence of a gas atmosphere. Moreover, morphology (sample roughness) and optical properties (refractive index, extinction coefficient) were measured of obtained thin films deposited on glass substrate using spin coating method. The study showed that obtained thin films of copolymers shows the possibility of using such polymers in the implementation of gas sensing structures.

Polymer planar waveguide broadband differential interferometer

In the paper the planar waveguide based on SU-8 polymer were made on 2μm of silica (SiO2) on silicon (Si) substrates in order to obtain base for broadband interferometer. Analysis and calculation of sensitivity for single mode broadband differential interferometer were performed. Paper presents preliminary tests and analysis of such structures. Dilution of SU-8 solution for obtaining thin layer (below 500 nm) followed by elipsometric measurements is presented.