积分指数 meaning in Chinese

exponential integral
integral exponential

Based on the nonlinear paraxial equation and b - t theory , a differential equation , which describes the small - scale self - focusing in gain ( loss ) media has been derived . the change rule of the maximal gain frequency , cutoff frequency and integral exponential gain have been analyzed approximately
我们首先从非线性近轴波方程出发，基于b - t理论的思想，在考虑了介质的增益(损耗)特性的情况下，推导得出了小尺度自聚焦所满足的微分方程，并通过近似方法分析了最大增长频率、截止空间频率及积分指数增益等的变化规律。