PROBLEM TO BE SOLVED: To provide an absorbance origin standard capable of easily cleaning a light sending end and a light receiving end of a light measuring instrument when setting the origin of the absorbance.SOLUTION: This absorbance origin standard 1 is used for the light measuring instrument 26 that measures light absorption characteristics of a light-scattering specimen in a state where an incident point of the measuring light entering the light-scattering specimen is separated from the detection point of the measuring light from the light-scattering specimen. The absorbance origin standard is integrally provided with a light-scattering plate 3 allowing the measuring light to scatter and transmit in its inside, and a cleaning section 2 for cleaning the light sending end 7 and the light receiving end 9 of the light measuring instrument 26, after the cleaning part 2 removes the contamination objects stuck to the light sending end 7 and the light receiving end 9 of the light measuring instrument 26, introduces the measuring light emitted from the light sending end 7 from the surface of the light-scattering plate 3 to the interior of the light-scattering plate 3, and allows it to pass through the interior of the light-scattering plate 3, to go out from the surface of the light-scattering plate 3 to the outside the light-scattering plate 3 and to arrive at the light receiving end 9.COPYRIGHT: (C)2009,JPO&INPIT【課題】 吸光度の原点を設定する際に、光測定装置の送光端と受光端とを容易に洗浄することができる吸光度原点標準器を提供することを目的とする。【解決手段】 光散乱性試料への測定光の入射点と光散乱性試料からの測定光の検出点とが離れている状態で、光散乱性試料の光吸収特性を測定する光測定装置26に用いられる吸光度原点標準器1であって、測定光が内部を散乱透過可能な光散乱板3と、光測定装置26の送光端7と受光端9とを洗浄する洗浄部2とを一体的に備え、洗浄部2によって、光測定装置26の送光端7と受光端9とに付着した汚染物質を除去した後、送光端7から出射された測定光を、光散乱板3の表面から光散乱板3の内部に入れ、光散乱板3の内部を通過させ、そして光散乱板3の表面から光散乱板3の外部へ出して、受光端9に到達させることを特徴とする。【選択図】図1
