Apparatus for an interference-based distance measurement, comprising - a measurement reflector (1; 100; 200), - a light source (16; 116; 216), - a splitter element which splits a beam emitted by the light source (16; 116; 216) into at least one measurement beam and at least one reference beam, wherein the measurement beam impinges on the measurement reflector (1; 100; 200) at least twice further down the beam path, - a merging element at which the measurement beam and the reference beam reach a state of interfering superposition, and comprising - a detector arrangement (18; 118; 218), by means of which at least one distance signal in respect of the distance between the measurement reflector (1; 100; 200) and one or more other components of the apparatus along a measurement direction (z) is generable from the interfering measurement and reference beams (M, R), wherein the measurement reflector (1; 100; 200) is arranged with a variable distance in relation to at least some of the components, characterized - in that the splitter element is embodied as a splitter grating (11; 111; 211) and the light source (16; 116; 216) emits the beam parallel to the surface of the measurement reflector (1; 100; 200) in the direction of the splitter grating (11; 111; 211), wherein the splitter grating (11; 111; 211) is arranged perpendicular to the surface of the measurement reflector (1; 100; 200) and - in that, between the splitter grating (11; 111; 211) and the merging element, the beam paths of the measurement and reference beam (M, R) each extend in mirror-symmetric fashion with respect to a plane of symmetry, which is oriented perpendicular to the surface of the measurement reflector (1; 100; 200), and - in that, between the splitter grating (11; 111; 211) and the merging element, at least two deflection elements (13.1, 13.2, 14.1, 14.2; 113.1a, 113.1b, 113.2a, 113.2b, 114.1a, 114.1b, 114.2a, 114.2b; 213.1, 213.2, 214.1, 214.2) are in each case arranged in the beam path of the reference beam and the measurement beam, wherein a deflection effect either along the measurement direction (z) or along and perpendicular to the measurement direction (z) results on the incident beam by way of each deflection element (13.1, 13.2, 14.1, 14.2; 113.1a, 113.1b, 113.2a, 113.2b, 114.1a, 114.1b, 114.2a, 114.2b; 213.1, 213.2, 214.1, 214.2). - a measurement reflector (1; 100; 200), - a light source (16; 116; 216), - a splitter element which splits a beam emitted by the light source (16; 116; 216) into at least one measurement beam and at least one reference beam, wherein the measurement beam impinges on the measurement reflector (1; 100; 200) at least twice further down the beam path, - a merging element at which the measurement beam and the reference beam reach a state of interfering superposition, and comprising - a detector arrangement (18; 118; 218), by means of which at least one distance signal in respect of the distance between the measurement reflector (1; 100; 200) and one or more other components of the apparatus along a measurement direction (z) is generable from the interfering measurement and reference beams (M, R), wherein the measurement reflector (1; 100; 200) is arranged with a variable distance in relation to at least some of the components, characterized - in that the splitter element is embodied as a splitter grating (11; 111; 211) and the light source (16; 116; 216) emits the beam parallel to the surface of the measurement reflector (1; 100; 200) in the direction of the splitter grating (11; 111; 211), wherein the splitter grating (11; 111; 211) is arranged perpendicular to the surface of the measurement reflector (1; 100; 200) and - in that, between the splitter grating (11; 111; 211) and the merging element, the beam paths of the measurement and reference beam (M, R) each extend in mirror-symmetric fashion with respect to a plane of symmetry, which is oriented perpendicular to the surface of the measurement reflector (1; 100; 200), and - in that, between the splitter grating (11; 111; 211) and the merging element, at least two deflection elements (13.1, 13.2, 14.1, 14.2; 113.1a, 113.1b, 113.2a, 113.2b, 114.1a, 114.1b, 114.2a, 114.2b; 213.1, 213.2, 214.1, 214.2) are in each case arranged in the beam path of the reference beam and the measurement beam, wherein a deflection effect either along the measurement direction (z) or along and perpendicular to the measurement direction (z) results on the incident beam by way of each deflection element (13.1, 13.2, 14.1, 14.2; 113.1a, 113.1b, 113.2a, 113.2b, 114.1a, 114.1b, 114.2a, 114.2b; 213.1, 213.2, 214.1, 214.2).