Abstract: A belt grinding apparatus for grinding the tips of rotor blades supported on a rotating rotor. A casing contains the rotatable rotor. An opening in the casing permits access of a grinding belt into the casing where the belt grinds the tips of the blades rotating past. The belt grinding apparatus being attached at the opening at a parting line in the casing.

Abstract: A method for shortening one or more rotor blade(s) (2) of a turbomachine (3) by removal of material at the blade tip, and apparatus (1; 19) for carrying out the method: a belt grinding apparatus (1; 19) shortens the rotor blades (2) and a contour of the blade tip is generated by a relative movement of the blade tip along the static belt grinding apparatus.

Abstract: An optical coupler (1) for coupling light in/out of an optical receiving/emitting structure comprises an optical fiber (100), a supporting device (200) to support the optical fiber (100) comprising a supporting structure (210) in which the optical fiber is arranged, and a covering device (300) to cover the supporting structure. An end face (E100a) of the optical fiber (100) is configured to reflect the light to one of the supporting device (200) and the covering device (300) comprising a first area and a second area (210, 220, 310, 320) being provided with a respective different index of refraction or a change of the respective index of refraction so that the first area (310) is configured as one of an optical waveguide (311) and at least one optical lens (312) being embedded in the second area and forming an optical pathway in said one of the supporting device and the covering device.

Abstract: A fiber coupling device for coupling of at least one optical fiber is disclosed. The fiber coupling device comprises at least one opto-electronic and/or photonic chip comprising at least one opto-electronic and/or photonic integrated element capable of emitting and/or detecting electromagnetic radiation. The fiber coupling device is configured for coupling the at least one opto-electronic and/or photonic integrated element to at least one fiber end-piece of an optical fiber having a reflection surface and a convex exit and/or entrance surface. The fiber coupling device further comprises a fiber end-piece alignment substrate configured for locally contacting and thereby supporting at least one convex exit and/or entrance surface of at least one fiber end-piece in an aligned position relative to the at least one opto-electronic and/or photonic integrated element.

Abstract: A method for shortening one or more rotor blade(s) (2) of a turbomachine (3) by removal of material at the blade tip, and apparatus (1;19) for carrying out the method: a belt grinding apparatus (1;19) shortens the rotor blades (2) and a contour of the blade tip is generated by a relative movement of the blade tip along the static belt.