SYNOPSYS 光学设计软件课程四十：从Scratch开始的非球面相机镜头

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在开发一款现代手机镜头或针孔间谍相机时，设计师们越来越多地使用非球面。它们通常是很小的塑胶元件，尽管制作模具很昂贵，但镜头可以大量生产，成本很低。甚至可以用法兰机直接模压到元件上，使组装更简单，这种方法可以使某些元件尺寸保持在非常小的公差范围内。 ib 'l:GM  
为帮助设计此类系统，DSEARCH™可以对具有非球面的系统进行全局搜索。 建议用户阅读SYNOPSYS™用户手册中关于这一强大功能的介绍。 我们在此给出一个如何将DSEARCH用于典型系统的示例。

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    PROJ                ! start project timer +h/OQ]`/m  
    CCW                 ! clear command window U?|A3;,xh  
    CORE 16             ! use 16 cores for speed CdCY#$Z  
    DSEARCH 1 QUIET      ! start DSEARCH; put best lens in library location 1 Gs|a$^V|o  
    SYSTEM                ! define the system specs }id)~h_@  
    ID DSEARCH ASPHERIC CAMERA LENS ! identification YqXN|&  
    OBB 0 41.3 .285     ! infinite object, semi field 41.3 degrees, semi ap. 0.285  PBW_9&d  
    UNI MM           ! lens will be in millimeters H(--hG5}  
    WAVL CDF          ! use visual wavelengths at C, d, and F lines P8=J0&5  
    END           ! end of system section dc~vQDNw[X  
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    GOALS           ! define the goals here il{x?#Wrb  
    ELEMENTS 5       ! we want a four-element lens with a cover glass rfQs 7S;G  
    BACK 0.4 SET      ! ask for 0.4 mm back focus distance ,K6ODtw.  
    FNUM 2.7 10       ! ask for F/2.7, weight of 10 P|?nx"c  
    THSTART 1          ! global search use thicknesses 1 mm WdC7CK  
    RSTART 30          ! and starting radius of 30 mm +/n]9l]#h  
    ASPH Q           ! use conic constant even in quick mode !@Vj&>mH$  
    ASPH 3           ! allow three aspheric terms: CC, 4th, 6th power of aperture W^ask[4
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    DELAY OFF          ! these runs are fast, so don’t ask to continue on timeout
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    ANNEAL 10 1 Q      ! anneal each case, temp 10 degrees, cool 1, including quick xDekC~Zq  
    SNAP 5             ! redraw PAD screen every five passes L
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    STOP FIRST      ! put the stop in front WTt /y\'6  
    STOP FIXED      ! and keep it there rk,64(   
    QUICK 50 50      ! run quick mode 50 passes, then real mode 50 2++$ Ql/  
    NGRID 6          ! 6x6 grid of rays in pupil 0L"uU3  
    NPASS 50           ! 50 passes in the MACro when finished s/E9$*0  
    TOPD           ! correct both transverse aberrations and OPDs ;YQ6X>
 
    FOV 0.2.4.6.8 1     ! correct six field points jL4"FTcE]3  
    FWT 5 4 3 3 3 3     ! with these weights wT;;B=u}G  
    COVER .3 1.51872 64 ! the cover glass will be 0.3 mm thick with this GLM F3Da-6T@  
    PLASTIC 1 3 5 7     ! the four elements will be plastic "Ya;
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    END                   ! end of goals section #&S<{75A  
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    SPECIAL AANT        ! start of special AANT section; these go into the merit fn. M_7
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    ACC 1.0             ! center thickness no more than 1.0 mm "4smW>f:%  
    ACM .2 .1 .2        ! and no thinner than 0.2 mm {B
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    ACA 60              ! avoid critical angle; 60 degrees from surface normal 4T&Jlu?:  
    AEC .2 .1 .2        ! keep edges over 0.2 mm \B/( H)Cd*  
    M 1.35 10 A P YA 1  ! target the chief ray at three field points EOqV5$+  
    M .945 10 A P YA .7 ! to control distortion ^H<VH  
    M .54 10 A P YA .4 GLV`IkU %  
    END                 ! end of AANT section CSm(yB{|pC  
    GO                  ! DSEARCH runs }!s$ /Kn  
    PROJ                ! when it is finished, see how long the run took.

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    GNO     0.000000     0.094362      6  M     0.900000

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