A new scheme that shows large angular dispersion is proposed and demonstrated. The key idea to this method is a virtually imaged phased array (VIPA). The angular dispersion of a VIPA is 10–20 times larger than those of common diffraction gratings, which have blaze angles of ~30 deg. With the VIPA, wavelength demultiplexing for 10 channels with 0.8-nm spacing is achieved. Low polarization-state dependence (~0.1 dB) is also confirmed.
© 1996 Optical Society of America
M. Shirasaki, "Large angular dispersion by a virtually imaged phased array and its application to a wavelength demultiplexer," Opt. Lett. 21, 366-368 (1996)