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In the last few years many new types of light‐guiding optical film structures have been developed. Several applications have been published in the field of optical and optoelectronic integrated circuits, sensor‐elements, etc. The basic component of these systems is the optical waveguide which can be realised with optical fibres or fabricated as a layer structure from different dielectrics and many kinds of glasses. The purpose of this paper is to describe some problems and solutions of optical waveguide thick film manufacturing and also connecting techniques with optical fibres.

The majority of methods for the optical monitoring of gases can be divided into two main groups. In the first, the intrinsic optical properties of the gas are exploited to sense it. In the second group, an indicator is used to transduce the gas concentration into a measurable optical parameter. Most gas sensors are usually sensitive to only one parameter of the monitored gas. This paper contains a description of a gas multisensor that is suitable for measuring gas concentration and pressure at the same time. It needs a special sensor construction that can measure the mentioned properties in parallel. The essence of this sensor is the double rle of the diaphragm. This means that the diaphragm itself is for sensing the pressure and suitable layer with an immobilised reagent is applied on top of the diaphragm for sensing the concentration of the gas. The sensing method is a fibre guided incident light beam to the diaphragm's surface. The incident beam passes through the concentration‐sensitive layer twice as the diaphragm's surface reflects it. The properties of the reflected beam contain the required information — pressure and concentration — about the measured gas. At the output of the system the reflected light intensity is proportional to pressure and the spectrum is promotional to concentration of gas. The paper describes the design and results in detail.

‘Soldering and Cleaning in Electronics’ international conference, including an exposition, took place in Brno on 12–13 October 1993. The conference was organised by SMT‐Info, together with the ISHM‐Czech and Slovak Chapter. The purpose of this common action was to bring together the professionals in surface mount technology and thick film technology. In the framework of the conference, in which 130 home and foreign delegates participated, the annual meeting of the ISHM‐Czech and Slovak Chapter took place.