Disclosed is an optical measurement device including a first light source, an optical element that condenses a light beam emitted from the first light source, a light irradiator that irradiates the light beam onto an object; and a photo detector that detects reflected light or scattered light of the light beam from the object through an imaging system, the light beam being irradiated onto the object, wherein a first optical path length from the first light source to a first conjugate image of the first light source by the optical element is different from a second optical path length from the photo detector to a second conjugate image of the photo detector by the imaging system at least in a first direction.