Stroboscopic observation of magnetic bubble circuits using a gated image-intensifier tube

Abstract

A technique using a gated image‐intensifier tube for stroboscopic viewing of magnetic bubble motion in field access devices is described. Adequate illumination of bubbles propagating in a 100‐kHz rotating field was obtained with a conventional microscope illuminator and a 50× objective using gate pulses as short as 0.5 μsec at repetition rates as low as 10 kHz. Observation of bubbles propagating through a chevron expander showed that lateral growth is asymmetric, indicating that an asymmetrically located bubble input port would give improved performance. Shorter pulses and higher repetition rates should permit observation of bubbles propagating in excess of 1 MHz.