TY - JOUR T1 - A Double-pass femtosecond Offner Stretcher Design with Minimized Spatial Chirping and Spectral Divergence TT - طراحی پهن‌کننده دوبار عبور لیزر فمتوثانیه با چرپ‌شدگی فضایی و واگرایی طیفی کم بر اساس پیکربندی آفنر JF - opsi JO - opsi VL - 21 IS - 0 UR - http://opsi.ir/article-1-602-en.html Y1 - 2015 SP - 425 EP - 428 KW - Offner stretcher KW - Ray tracing method KW - Spatial chirping KW - Spectral divergence N2 - In this paper we describe the design of a double-pass Offner stretcher with 50 nm bandpass which stretches a 50 fs pulse to 750 ps. Optical elements dimensions and the system design have been analyzed by using ray tracing method. The results of our investigation show that the output pulse quality can easily be improved by making a little change in design. The best design, with minimum spatial chirping and spectral divergence, has been found. M3 ER -