A beam imaging detector was developed by coupling a multi-strip anode with delay line readout to an E$times$B microchannel plate (MCP) detector. This detector is capable of measuring the incident position of the beam particles in one-dimension. To assess the spatial resolution, the detector was illuminated by an $alpha$-source with an intervening mask that consists of a series of precisely-machined slits. The measured spatial resolution was 520$mu$m FWHM, which was improved to 413$mu$m FWHM by performing an FFT of the signals, rejecting spurious signals on the delay line, and requiring a minimum signal amplitude. This measured spatial resolution of 413$mu$m FWHM corresponds to an intrinsic resolution of 334$mu$m FWHM when the effect of the finite slit width is de-convoluted. To understand the measured resolution, the performance of the detector is simulated with the ion-trajectory code SIMION.