用横向光热偏转技术(TPDS)测量光学薄膜的弱吸收,灵敏度达10~(-5).因为薄膜样品在调制频率较低时属热薄试样,本文基于这一原理实现了TPDS的精密定标. The weak absorbance of the optical thin film was measured by transverse light thermal deflection technique (TPDS) with a sensitivity of 10 ~ (-5) .Because the thin film samples were hot thin samples with low modulation frequency, this paper based on this principle to achieve the TPDS precision target.