Fig. 4From: Development of low-cost sky-scanning Fabry-Perot interferometers for airglow and auroral studiesExamples of fringe images obtained by (a) FP01 for 557.7 nm (sky), (b) FP01 for 630.0 nm (sky), and (c) FP01 for 632.8 nm (laser) on January 24, 2009, at Tromsø, and (d) FP02 for 630.0 nm (sky), and (e) FP02 for 632.8 nm (laser) on August 17, 2009, at Shigaraki.Back to article page