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Background High‐intensity focused ultrasound (HIFU) for non‐invasive treatment of a range of internal pathologies including cancers of major organs and cerebral pathologies is in exponential growth. Systems, however, operate at relatively low frequencies, in the range of 200‐2000 kHz as required for deep axial penetration of the body. HIFU utilizing frequencies in excess of 15 MHz has so far not been explored, but presents an opportunity to extend the HIFU modality to target specific dermal lesions and small animal research. Materials and methods A new 20‐MHz HIFU system (TOOsonix ONE‐R) with narrow focus corresponding to the dermis was studied in acoustic skin equivalents, for example, in a tissue‐mimicking gel and in bovine liver. HIFU lesion geometry, depth, and diameter were determined. The temperature increase in the focal point was measured as a function of acoustic power and the duration of HIFU exposure. Results The system produces highly reproducible ultrasound lesions with predictable and configurable depths of 1‐2 mm, thus corresponding to the depth of the human dermis. The lesion geometry was elongated triangular and sized 0.1‐0.5 mm, convergent to a focal point skin deep. Focal point temperature ranged between 40 and 90°C depending on the chosen setting. Observations were confirmed ex vivo in bovine liver and porcine muscle. Variation of acoustic power and duration of exposure produced linear effects in the range of the settings studied. Thus, effects could be adjusted within the temperature interval and spatial field relevant for clinical therapy and experimental intervention targeting the dermal layer of human skin. Conclusion The tested 20‐MHz HIFU system for dermal applications fulfilled key prerequisite of narrow‐field HIFU dedicated to cutaneous applications regarding reproducibility, geometry, and small size of the applied ultrasound lesions. Controlled adjustment of acoustic lesions within the temperature range 40‐90°C qualifies the system for a range of non‐ablative and ablative applications in dermatological therapy.

A simple and inexpensive low‐temperature cofired ceramic (LTCC) microfluidic device with integrated optical fibers is designed, manufactured, and tested with positive results. Fluidic channels, mixer, detector, optical fiber, light source, light detector, heater, and temperature sensor are integrated in one LTCC module. The optical system in the LTCC microsystem permits measurements of light transmittance and fluorescence. The design, technology, and results of the module's evaluation are presented.

This paper presents possibility of laser application for fabrication of 3D elements and structures. The Aurel NAVS‐30 Laser Trimming and Cutting System with special software was used. It was applied successfully for fabrication of vias (minimum diameter – 50 μm) in fired and unfired LTCC ceramics and channels with width between 100 μm and 5 mm. The achievements and problems are presented and discussed. The influence of lamination process on quality of vias and channels as well as the problems connected with interaction of laser beam with ceramic tapes are shown. Three‐dimensional resistors and microfluidic system were successfully designed and fabricated based on our investigations. Chosen electrical and thermal parameters of constructed devices are shown, too.

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