Patent ID: 8797521

Claim:
Process for measuring the angle of rotation of two objects ( 11 , 12 ) rotating in relation to each other, with a transmitter ( 20 ) which is assigned to one of the objects ( 11 ), and with an element ( 30 ) which influences the direction of polarization, where the transmitter and the element ( 30 ) which influences the direction of polarization rotate relative to each other as a function of the rotation angle, and where the luminous intensity passing through, or reflected by, the element ( 30 ) influencing the direction of polarization and measured by a receiver ( 40 ) is evaluated as a signal dependent on the rotation angle, and where the receiver ( 40 ) has at least two groups ( 41 , 42 , 43 , 44 ), each with at least two receiver elements ( 41 a , 41 b , 41 c , 41 d , 41 e , 41 f , 41 g , 41 h , 42 a , 42 b , 42 c , 42 d , 42 e , 42 f , 42 g , 42 h , 43 a , 43 b , 43 c , 43 d , 43 e , 43 f , 43 g , 43 h , 44 a , 44 b , 44 c , 44 d , 44 e , 44 f , 44 g , 44 h ), such that each receiver element ( 41 a - 44 h ) is designed as a detector that is sensitive to polarization, and where the polarization planes of the receiver elements ( 41 a - 44 h ) in each group ( 41 , 42 , 43 , 44 ) are rotated in relation to each other, wherein the reception signals of at least two of the receiver elements ( 41 a , 41 b , 41 c , 41 d , 41 e , 41 f , 41 g , 41 h ; 42 a , 42 b , 42 c , 42 d , 42 e , 42 f , 42 g , 42 h ; 43 a , 43 b , 43 c , 43 d , 43 e , 43 f , 43 g , 43 h ; 44 a , 44 b , 44 c , 44 d , 44 e , 44 f , 44 g , 44 h ) are evaluated independent of each other in a monitoring mode, wherein the different groups ( 41 , 42 , 43 , 44 ) of receiver elements are positioned so as to be spatially separate from each other, wherein the different groups ( 41 , 42 , 43 , 44 ) are identically designed, such that in each of the groups there is positioned one of the receiver elements with the same polarization plane as another one of the receiver elements belonging to a different group, wherein the reception signals of at least two of the receiver elements ( 41 a - 44 h ) having the same polarization planes can be compared with each other in the monitoring mode, and wherein in the monitoring mode, the reception signals of at least two of the receiver elements ( 41 a - 44 h ) are converted into an angle, and the computed angle is compared to the angle which was computed from the reception signals of at least two other receiver elements having the identical relative angular offset in their polarization planes.