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We report about properties of large core plastic planar optical bend waveguides. The dimensions of the waveguides were to be compatible with the commonly used plastic optical fiber with diameter 750 µm and the bend radii of the waveguides varied from 30 to 1 mm. The waveguides were made by engraving of a U-groove by using CNC machining into poly(methyl methacrylate) substrate; the waveguide core layers were made of Norland Optical Adhesive UV photopolymer. We experimentally confirmed that fabricated bends may have the total bend losses A for radii 30 mm 4.1 dB/cm at 850 nm, 4.8 dB/cm at 650 nm and 5.63 dB/cm at 532 nm. These bend waveguides are viable for short reach visible and infrared optical communication with easy and low cost installations.

This article deals with benefits of PVD and CVD coatings applied to cutting inserts during face milling technology. The coatings deposited on applied cutting inserts were used to extension the tool life. Machining process was carried out on the conventional vertical milling machine tool. This machining process was performed without coolant. The set up of cutting conditions were constant throughout the machining and low-alloy Cr-Mo steel DIN 42CrMoS4 (W. Nr. 1.7227) was used as workpiece material in the realized process of experiments. The aim of this investigation was to compare coated and uncoated changeable cutting inserts clamped in the milling cutter and find out the benefits of PVD or CVD coatings during realization of face milling process. The monitored parameters were the force load measured by piezoeletrical dynamometer Kistler 9257B and the obtained flank wear measured by optical microscope.

Regarding the terrestrial laser scanning accuracy, one of the main problems is the noise in measured distance which is necessary for the spatial coordinates´ determination. In this paper the technique of using the wavelet transformation for the reduction of the noise in the laser scanning data is described. This method of filtration is made in “post processing” and due to this fact any changes in the measuring procedure in the field shouldn´t be done. The creation of the regular matrix is needed to apply image processing. This matrix then makes the range image. In the paper real and simulated efficiency tests of wavelet transformation, the final summary and advantages or disadvantages of this method are introduced.