fixed-focus英'fɪkstf'əʊkəs美'fɪkstf'əʊkəsCOCA³¹⁵¹¹¹⁺⁴BNC²³⁶²¹³⁺¹ 基本例句 固定焦点¹⁰⁰ The principle of photo fixed-focus apparatus, GDDJ-1, the analysis of precision and the way to improve the precision of the apparatus are discussed. 本文介绍了 GDDJ-1光电定焦仪的工作原理，精度分析以及提高该仪器的精度办法。 cnki