Patent ID: 8491756

Claim:
A device for determining the water content of a target ( 1 ), the device comprising at least one source of target radiation ( 2 ), at least one source of reference radiation ( 4 ) oriented toward a target surface ( 10 ), and at least one detecting element ( 3 ) for measuring the intensity of radiation reflected back by the target surface, the at least one source of target radiation ( 2 ), the at least one source of reference radiation ( 4 ), and the at least one detecting element ( 3 ) being arranged immediately opposite the target surface ( 10 ) during use, and a pressurizing device using a gas by which an artificial movement of a gas atmosphere is created in an area of optical paths between the at least one source of target radiation ( 2 ) and the target surface ( 10 ) and/or between the at least one source of reference radiation ( 4 ) and the target surface ( 10 ) and/or between the target surface ( 10 ) and the at least one detecting element ( 3 ); wherein the source of target radiation ( 2 ), the source of reference radiation ( 4 ), and the detecting element ( 3 ) are arranged in a housing ( 15 ), in which corresponding passages are formed in a wall ( 18 ) of the housing ( 15 ), through which passages beams emitted by the source of target radiation ( 2 ) and the source of reference radiation ( 4 ) exit and a beam reflected by the target surface ( 10 ) enters; wherein the passages in the wall ( 18 ) of the housing ( 15 ) are formed as through holes ( 41 , 42 , 43 ) in a holder element ( 31 , 31 ′), at the ends of which inside the housing ( 15 ) the source of target radiation ( 2 ), the source of reference radiation ( 4 ), and the detecting element ( 3 ) are arranged, while their opposite ends are directed towards the target surface ( 10 ) during use; wherein optical axes of the source of target radiation ( 2 ), the source of reference radiation ( 4 ), and the detecting element ( 3 ) are oriented along central axes ( 21 , 22 , 23 ) of the through-holes ( 41 , 42 , 43 ); wherein the through holes ( 41 , 42 , 43 ) of the holder element ( 31 , 31 ′) each have at least one side inlet ( 71 , 72 , 73 ) connected to the pressurizing device and oriented perpendicularly with respect to the central axes ( 21 , 22 , 23 ) through which the gas is introduced into the through holes ( 41 , 42 , 43 ); and wherein a diameter of the through-holes ( 41 , 42 , 43 ) and a diameter of the at least one side inlet ( 71 , 72 , 73 ) are approximately equal.