Abstract: There is provided an apparatus (300) for measuring a distance to a target (312), comprising: a transmitter (302) configured to transmit an optical pulse (310) towards the target (312), a receiver channel (304) configured to receive the optical pulse (310) reflected from the target (312), and a processor (306) configured to measure a time intervaf between the transmission and detection of the optical pulse (310) at a predefined amplitude threshold level (11OA, 110B), to determine a time domain parameter from the detected optical pulse (310) at one or more amplitude threshold levels (110A, 110B), to convert the time domain parameter value into a correction value by a conversion model; to correct a timing error in the measured time interval by the correction value, and to convert the error-corrected time interval into a distance to the target (312).

Abstract: A single pulse semiconductor laser operating in the gain-switching regime comprises a plane asymmetric waveguide and an active layer in the waveguide, the ratio of a thickness of the active layer to an optical confinement factor of the laser being extremely large, larger than about 51 ?m, for example.

Abstract: The invention relates to a method and an arrangement for performing triggering and for determining a triggering moment. In the solution, a unipolar electrical pulse of a detector (106, 118) is converted between the detector (106, 118) and a first amplifier (108, 120) succeeding the detector into at least one bipolar electrical oscillation. The bipolar electrical oscillation is amplified with at least one amplifier (108, 120) and triggering is performed at a zero level between the extreme values of the bipolar electrical oscillation. In addition, a triggering moment is determined, at which the amplified bipolar electrical oscillation crosses the zero level between its extreme values.

Abstract: The invention relates to a method and an arrangement for performing triggering and for determining a triggering moment. In the solution, a unipolar electri-cal pulse of a detector (106, 118) is converted between the detector (106, 118) and a first amplifier (108, 120) succeeding the detector into at least one bipolar electrical oscillation. The bipolar electrical oscillation is amplified with at least one amplifier (108, 120) and triggering is performed at a zero level between the extreme values of the bipolar electrical oscillation. In addition, a triggering moment is determined, at which the amplified bipolar electrical oscillation crosses the zero level between its extreme values.

Abstract: The invention relates to a method for determining the distance of a target in difficult industrial conditions, method in which (i) one of the gamma quanta produced from a radioactive source in annihilation and traveling in opposite directions is aimed at the target and the other one at a detector, which detects it, and time measuring starts; (ii) the quantum Compton-scattered from the target is detected by the same or a separate detector, and time measuring stops; (iii) the distance of the target is calculated from the time difference between (i) and (ii). The invention also relates to a device for carrying out the method, the device comprising a radioactive source, a scintillation crystal counter/counters, a time-amplitude converter (TAC) and a pulse height analyzer (PHA).

Abstract: An FM or PM signal is demodulated so that the cycle time of the modulated input signal is measured using a time-to-digital converter comprising a counter that uses a moderate clock frequency as a reference clock, a digital delay line interpolator and a control circuitry. The counter is used for rough digitization and the delay line for interpolating the moment of zero-crossing inside a clock cycle. Total delay of the delay line, i.e., the range of time intervals the interpolator is able to measure, is actively kept equal to the cycle time of the reference clock. When the number of delay elements in the delay line is a power of two, the result of the delay line interpolator may be used directly as the least significant bits of the measurement.

Abstract: Designs of prior art art not usable in efficient dry-run target practice with hand firearms. The greatest drawbacks are, for instance, that it is not possible by the method to monitor the result of the dry-run training; that the method or means is not liable on ordinary guns without special measures or not at all or the method is so complicated that its implementation in practice causes that the means is too expensive to be in the personal possession and use of shooters. In order to eliminate said drawbacks, the invention is mainly characterized in that by a transmitter/receiver means attachable to conventional arms is emitted an optical beam towards a surface serving as the target which is set off from its surroundings due to its optic radiation reflecting properties relative to those of its surroundings, the hitting or missing of the beam being observed with the receiver on the basis of the return beam.