Browsing by Author "Pan"

Now showing 1 - 2 of 2

Blue-light generating femtosecond wavelength-tunable non-collinear optical parametric amplifier
(2006-09-12)
Pan
;
Ci-Ling
;
Huang
;
Jung Y.
;
Zhang
The present invention discloses a means of the generation of tunable femtosecond pulses from 380 nm to 465 nm near the degenerate point of a 405-nm pumped type-I BBO non-collinearly phase-matched optical parametric amplifier (NOPA). The tunable UV/blue radiation is obtained from sum frequency generation (SFG) between the OPA output and the residual fundamental beam at 810-nm and cascaded second harmonic generation (SHG) of OPA. With a pumping energy of 75 mJ at 405 nm, the optical conversion efficiency from the pump to the tunable SFG is more than 5% and the efficiency of SHG of the OPA is about 2%.
Tunable terahertz wavelength selector device using magnetically controlled birefringence of liquid crystals
(2009-01-27)
Chao
;
Ru-Pin
;
Pan
;
Ci-Ling
;
Chen
The present invention provides a tunable terahertz (THz) wavelength selector device, which includes a fixed phase retarder, a tunable phase retarder and a pair of linear polarizers to form a unit. The fixed phase retarder and tunable phase retarder basically utilizes liquid crystals to provide phase retardation, moreover, utilizing birefringence phenomenon possessed by liquid crystals can provide adequate phase retardation. The fixed phase retarder utilizes horizontal orientation of liquid crystal cell to provide fixed phase retardation, while the tunable phase retarder however utilizes homeotropic liquid crystal cell and a rotatable magnet to provide a tunable phase retardation, wherein the tunable phase retarder can provide the positive or negative phase retardation relative to the fixed phase retarder, based on the direction of the magnet's rotating axes and totally use the entire tunable range into adjusting frequencies which can pass through. Besides, the present invention can also serially connect multiple units described above so as to achieve a narrow enough band-pass bandwidth.