PROBLEM TO BE SOLVED: To provide a blood flow authentication device which is used for managing entrance/exit in a building such as a house and can sufficiently obtain information on a specific health condition from blood components of a finger of a person to be authenticated. I will provide a. SOLUTION: A second light source 3 and a third light source 5 are located on both sides of a finger F, and light emitted from the second light source 3 is emitted from a first optical path L1 and a third light source 5 reaching a first light receiving section 4. The second light path L2 through which the received light reaches the second light receiving unit 6 intersects on the ventral side of the finger F when viewed from the fingertip of the finger, and the control unit 8 causes the imaging unit 2 and the first light receiving unit 4 and A step of acquiring light transmitted through the finger F at a predetermined time interval using at least one of the second light receiving parts 6, and a wavelength obtained by using the first light receiving part 4 and the second light receiving part 6. This is solved by a blood flow authentication device that controls to execute a step of calculating biological information regarding blood of the finger F based on the information. [Selection diagram] Figure 1【課題】家屋などの建物における入退室の管理などを行うために用いられ、被認証者の指の血液成分から特定の健康状態に関する情報を十分に得られるようにすることができる血流認証装置を提供する。【解決手段】第二光源３及び第三光源５が指Ｆの両側に位置し、第二光源３から発せられた光が第一受光部４に至る第一光路Ｌ１と第三光源５から発せられた光が第二受光部６に至る第二光路Ｌ２が、指の指先から見たときに指Ｆの腹側で交差し、制御部８が、撮像部２と、第一受光部４及び第二受光部６の少なくとも一方を用いて時間的に所定の時間間隔にて指Ｆを透過した光を取得するステップと、第一受光部４及び第二受光部６を用いて得られた波長情報に基づいて指Ｆの血液に関する生体情報を算出するステップを実行するように制御する血流認証装置により解決する。【選択図】図１
