PROBLEM TO BE SOLVED: To provide a measurement base which can receive light including much information on blood components.SOLUTION: A measurement base has a body part 15 having a first face 16 and a second face 17 on which a finger 3 is put, a light projection part 23 that projects light in the direction in which the first face 16 and the second face 17 face, and a light receiving part 24 that receives light 30, which is the diffused reflection of the light 30 projected by the light projection part 23. From the first face 16 to the second face 17 a groove part 22 is installed, and the light projection part 23 and the light receiving part 24 are installed at the groove part 22.【課題】血液成分の情報を多く含んだ光を受光することができる測定台を提供する。【解決手段】指３が設置される第１面１６及び第２面１７を有する本体部１５と、第１面１６及び第２面１７が向く側に投光する投光部２３と、投光部２３が投光した光３０が乱反射した光３０を受光する受光部２４と、を備え、第１面１６から第２面１７にかけて溝部２２が設置され、投光部２３と受光部２４とは溝部２２に設置されている。【選択図】図３
