有限线宽 meaning in English

finite linewidth

The analytical solutions of the gain , dispersion and population difference in the steady state of an open ladder lasing without inversion ( lwi ) system are at first given when the phase fluctuation of the driving field is considered . then the effects of the driving field phase fluctuation on the gain , dispersion and population difference are analyzed by the numerical results from the analytical solutions . our research shows that the phase fluctuation of the driving field will results in a finite line width ; with the line width increasing , the gain decreases monotonously , however , variation of the dispersion isn ? t monotonous , it has a maximum value when the line width takes some value ; the line width varying can ? t lead to change lasing from without to with population inversion
给出了有驱动场位相涨落的开放的梯型无粒子数反转激光( lwi )系统增益、色散和布居数差的定态解析解,进而用得到的数值计算结果分析了驱动场位相涨落对增益、色散和布居数差的影响.研究结果表明,驱动场位相涨落将导致有限线宽;随着线宽的增加,系统增益单调地减小,但系统色散的变化并不是单调的,当线宽取某个值时,色散有极大值;线宽的变化不能导致无反转激光向反转激光的转变