There are lot, depending on your requirements. Anyway you can try: hMi!H.EX. YR~g&E#U^ 1, Refractive: an achromatic as positive + plano-convex as negative; /$I&D}uR` OR |wVoJO!O} 2, Reflective: two parabolic mirrors; f85j?Jm q'q'v
S Both of them affer nice spherical aberration performance. 3cQTl5, h/eKVRGs" Reminder: compute the laser beam density, ensure you have enough strong optical coating. 9OXrz}8C #r:J,D6* Good luck.
Hi, ,MOB+i(3*u )k29mqa` The following is a link of technical data of optical adhesives, hope it be helpful: k 2;m"F HRx#}hN?+ http://www.lienhe.com.cn/uvadh/NOA60.htm YJeZ{Wws gjyg`% Double check from your lens vendor waht type of adhesive they use for your cemented doublet. pN4!*7M !Me%W3 It is OK to use the spaced doublet design as a backup, if so, please pay a lot attention on the opto-mechanical design and assembling. ot(|t4^ &WvJg#f Again, good luck.