高功率光束吸收器的设计

为了实现4%取样后对剩余激光高达109 倍的吸收，给出一种光束吸收器的设计方法，推导了光束从进入吸收器到离开吸收器全过程中所对应的各种角度关系，包括入射光线与吸收器交点的夹角、光线从入射变为出射的翻转临界角、出射光线与吸收器交点的夹角、光线离开吸收器临界角等角度关系。进而计算出光线在与吸收器的每一个交点处的取样率，得到光束从进入吸收器到离开吸收器全过程的衰减倍率。以此设计一种光束吸收器并在软件中进行光线追迹分析，结果表明该吸收器的吸收倍率高达1011，满足激光吸收倍率要求并且和理论计算结果吻合；据此理论设计的实物吸收器也在激光系统中得到良好应用，得到调制度M1.2 和对比度C0.07 的近场图像，说明该设计方法是合理的。

Design of high power light absorber

In order to realize the 109 times absorption for residual laser after 4% sampling, a kind of design method of light absorber was given. From light entrance to light exit the absorber, total angle relations were derived, including the angle of entrance light intersection with the absorber, turnover angle from entrance to exit, the angle of exit light intersection with the absorber, and turnover angle of the light departure from the absorber. The calculated angles were taken into polarization formula, and the sampling efficiency from every intersection was gotten, and so the total process attenuation was obtained from light entrance to light exit the absorber. According to the above formulas, a kind of absorber was designed, and it was analyzed in optical software. The results show that the absorption can reach to 1011, which satisfies the absorption requirements and is identical with theory calculation; This kind of absorber has been used in the laser system well, near field image with modulation M1.2 and contrast C0.07 are gotten, so the design method is reasonable.