Patent ID: 6989549

Claim:
An optical gas sensor comprising: a measured gas cell with a cylindrical part defining a cylindrical space with a measured gas inlet; a reflective, flat first cover element; a reflective, flat second cover element arranged at a spaced location from and in parallel to the first cover element, said first and second cover element limiting the measured gas cell in a longitudinal axial direction, the height of the measured gas cell corresponding approximately to 1 to 3 times the diameter of the cover elements; a radiation source accommodated in said second cover element; a measuring detector and one reference detector accommodated in said second cover element, said radiation source being arranged displaced by 30% to 60% of the radius of the second cover element from a center of the second cover element and said detector elements being displaced by an equal amount of 25% to 35% of the radius of the second cover element from a straight line passing through the center of the second cover element, wherein the straight line extends at right angles to the diameter of the radiation source and the direction of displacement of the detector elements is opposite that of the radiation source and the detector elements are arranged mirror symmetrically to each other and at equal distance from the radiation source, wherein the distance amounts to 10% to 50% of the radius of the second cover element.