雷利(Reilley)等在1955年出提了一种新的精密比色方法——低吸光度法。使用低吸光法比色测定微量元素能提高测定的灵敏度和精密度,但是也带来工作曲线范围变窄的缺点。为了扩展低吸光度法的工作曲线范围,我们在1964年提出了双向低吸光度法。方法曾应用于矿石中微量锗的有机相直连萃取比色测定,取得了很好的效果。 In 1955, Reilley et al. Proposed a new method of precision colorimetry - the low absorbance method. The use of low absorbance colorimetric determination of trace elements can improve the sensitivity and precision of the determination, but also brings the shortcoming of narrowing the working curve range. In order to extend the working curve range of the low-absorbance method, we proposed a bi-directional low absorbance method in 1964. The method has been applied to the determination of trace germanium in the organic phase by direct colorimetric extraction and has achieved good results.