Abstract: The invention is directed to a method and a combined visibility measuring and precipitation measuring instrument for determining visibility, amount of precipitation and type of precipitation.

Abstract: The invention is directed to a method and a combined visibility measuring and precipitation measuring instrument for determining visibility, amount of precipitation and type of precipitation.

Abstract: The lidar arrangement (1) has a transmitter (3) for linearly polarized radiation (12), a receiver (5) with a first receiving device which measures intensity of the backscattered radiation (15) coinciding approximately with the transmitted radiation cone (12) in a polarization plane of the cone and in a perpendicular polarization plane, wherein the receiver further includes a second receiving device which measures the intensity of backscattered radiation (17) outside the transmitted cone (12), the outer backscattered radiation has the shape of a conical shell which surrounds the backscattered conical shell of the first mentioned backscattered radiation (15) and of the transmitted cone (12); the received separate radiation cones (15 and 17) are split in a polarization analyzing optical element into two mutually perpendicular partial light beams, each consisting of an inner partial beam portion (15a, 15b) and an outer partial beam portion (17a and 17b), the inner and outer partial beam portions are separately de

Abstract: An arrangement for in situ determination of the quantity of turbid matter, aerosol and/or dust in flue gas which flows through a flue by measurement of intensity of light irradiated by means of an optical transmitter in the flue, and dispersed on solid or fluid dispersion particles. The dispersion light is detected by a detector which is arranged outside of the bundle of rays of the transmitter and provided with a wide angle focusing optic. A woodsche horn absorbs the not dispersed part of the bundle of rays of the transmitter. The light source of the transmitter is formed as a xenon spark discharger with intensity maximum in the region of 350-600 nm, the detector signal is evaluated by an evaluating electronic circuit. The arrangement determines extremely low quantities of harmful matter.

Abstract: An onboard power supply and metering unit is connected, via an overboard cable e.g., 1000 meters long, to an underwater light-pulse projecting unit and a fluoroescence-sensing receiver unit. The operating power is transmitted to the underwater units by an onboard constant-current source, instead of a voltage source. Likewise, the output signal of the receiver unit is transmitted through the cable in the form of a current, not a voltage. The current of the receiver's photodiode is integrated, the peak value of the integral determined and held, this held value logarithmized, the logarithmized value sampled and held, and the held voltage converted to a current constituting the output signal. The offset of the peak detector and the input stage of the log amplifier are balanced automatically, by a balancing signal applied during pulse measurements, but derived between pulse measurements.