The fixation measurement method and apparatus is a first reflecting mirror including a diffractive member, and reflects light received from a light source to the second reflecting mirror via the diffractive member and is received from the second reflecting mirror. The first reflecting mirror that reflects the light through the diffraction member is rotated around the rotation axis, and the light reflected by the second reflecting mirror and then reflected by the first reflecting mirror is converted into one or more lights. It detects with a detection element. [Selection] Figure 1固視測定方法および装置は、回折部材を含む第１の反射鏡であって、光源から受けた光を回折部材を介して第２の反射鏡へ反射し、前記第２の反射鏡から受けた光を回折部材を介して反射する第１の反射鏡を、回転軸まわりに回転させ、第２の反射鏡で反射されその後第１の反射鏡で反射された光を、一つまたは複数の光検出素子で検出する。【選択図】図１
