SYNOPSYS 光学设计软件课程十三:带有Kinoform镜头的激光扩束器
i1/}XV -Q`Cq|s 在第11课中,您了解了如何使用普通球面透镜设计激光扩束器,并了解到需要多个透镜元件才能获得良好的性能。 第12课采用相同的设计,使用两个非球面元件,效果极佳。 本课程将证明您可以使用DOE(衍射光学元件)。 ~!
Lw1]& 目标是将腰半径为0.35mm的HeNe激光器转换成直径为10mm且均匀至10%以内的光束。 C"T ,MH 这是我们初始的输入文件: rqvU8T7A RLE ! Beginning of lens input file. 。 O=O(3Pf> ID KINOFORM BEAM SHAPER
o?R,0 - WA1 .6328 ! Single wavelength tm xP Oe UNI MM ! Lens is in millimeters PbUI!Xqe` OBG .35 1 ! Gaussian object; waist radius -.35 mm; define full aperture = 1/e**2 point. Nz]aaoO4 1 TH 22 ! Surface 2 is 22 mm from the waist . VA]ZR+m 2 RD -2 TH 2 GTB S ! Guess some reasonable lens parameters; use glass type SF6 from Schott catalog rZ866\0 SF6 w?ai,Pw 3 TH 20 ! Surface 3 is a kinoform on side 2 of the first element oBUh]sR{. 3 USS 16 ! Defined as Unusual Surface Shape 16 (simple DOE) [u\CD sX CWAV .6328 ! Zones are defined as one wave phase change at this wavelengt <jL#>L%% HIN 1.7988 55 ! Assume the zones are machined into the lens. You can also apply ! a film of a different index. h2}am:%mC RNORM 1 "X?LAo F>Mr<k=@; 4 TH 2 GTB S byj[u!{ SF6 2?*1~ 5~I 4 USS 16 2wOy}: CWAV .6328 c20|Cx2m HIN 1.7988 55 fbL!=]A*3 RNORM 1 `hF;$ ! The first side of the second element is also a DOE 7+]F^
6 5 CV 0 TH 50 ! Start with a flat surface &
3I7]Wm 7 ! Surfaces 6 and 7 exist w2<*$~C] AFOCAL ! because they are required for AFOCAL output. XkoW L END ! End of lens input file. n1`T#%e NQ3|\<Wt 我们给第2个表面指定了一个合理RD值。 这是现阶段还没有DOE的非球面系数的系统: InX{V|CW? 光束被扩展但没有准直,并且强度分布仍然是高斯输入光束的强度分布。 任务是找到能够实现我们两个目标的DOE OPD目标。 首先,让我们将第二个透镜的两边保持为平面。 这是优化MACro: /kb$p8!C". PANT ! Start of variable parameter definitions. K#U{<pUP RDR .001 ! This is a very small beam, so use smaller derivative increments to start with VY s_` V*`n& 2 RAD r2)pAiTM* VLIST TH 3 ! Vary the airspace R]fYe#!" VY 3 G 26 ! Vary term Y**2, i-Ljff VY 3 G 27 ! Y**4, /op/g]O} VY 3 G 28 ! and Y**6 "x.88,T6 z5I^0' VY 4 G 26 ! Do the same at surface 4 ;W4:#/~14 VY 4 G 27 `i{4cT8: VY 4 G 28 d TgM"k 4jD\]Q="1 END v @_?iC"` up7x)w: AANT ! Start of merit function definition z+2u-jG AEC [@s=J)H ACC 8ST~$!z$ LUL 150 1 1 A TOTL ! Prevent the system from growing too large 8s&2gn1 M 5 1 A P YA 0 0 1 0 5 ! Ask for a beam radius of 5 mm on surface 5 i!ds {`d n+S&!PB M 0 1 A P FLUX 0 0 1 0 6 ! Ask for a flux falloff of zero at several zones GHqBnE{B M 0 1 A P FLUX 0 0 .98 0 6 A< |