REFLECTION OPTICAL ELEMENT, AND INTERFERENCE SPECTROMETER

To provide a reflection optical element that can improve a degree of optical path freedom.SOLUTION: A reflection optical element 14 reflects incidence light upon each of a first reflection surface and second reflection surface mutually different in a position in a reference direction. The reflection optical element 14 comprises: a first reflection body 144 that has a plurality of first reflection elements 1444 tabular orthogonal to the reference direction, apart from each other in a first direction orthogonal to the reference direction, and forming the first reflection surface; a second reflection body 145 that has a plurality of second reflection elements 1452 tabular orthogonal to the reference direction, located respectively between adjacent two first reflection elements 1444 and 1444 of the plurality of first reflection elements 1444, and forming the second reflection surface, and is movable with respect to the first reflection body 144 in the reference direction; and a position change unit that changes a position of the second reflection body 145 with respect to the first reflection body 144 in the reference direction.SELECTED DRAWING: Figure 2 【課題】光路の自由度を高めることが可能な反射光学素子を提供すること。【解決手段】反射光学素子１４は、基準方向における位置が互いに異なる、第１反射面及び第２反射面のそれぞれにて入射光を反射する。反射光学素子１４は、基準方向に直交する平板状であり、且つ、基準方向に直交する第１方向にて互いに隔てられるとともに第１反射面を形成する複数の第１反射要素１４４４を有する第１反射体１４４と、基準方向に直交する平板状であり、複数の第１反射要素１４４４のうちの、隣り合う２つの第１反射要素１４４４，１４４４間にそれぞれ位置するとともに、第２反射面を形成する複数の第２反射要素１４５２を有し、且つ、基準方向にて、第１反射体１４４に対して移動可能な第２反射体１４５と、第１反射体１４４に対する第２反射体１４５の位置を、基準方向にて変更する位置変更部と、を備える。【選択図】図２