First X-ray imaging with a micromachined Wolter type-I telescope

Abstract

A light-weight Wolter type-I telescope for future space X-ray observations is prototyped by using micromachining technologies. Curvilinear micro pores with a width of 20 $$\upmu$$μm are fabricated with deep reactive ion etching. Sidewalls of the pores are smoothed with high temperature annealing. Then, two wafers are deformed to different curvature radii, 1000 and 333 mm. The two wafers are aligned using parallel X-ray beams which are dominated by Al-K$$_{\alpha }$$ź line at 1.49 keV. High angular and positional accuracies of the order of arcsec and $$\upmu$$μm are achieved using movable stages. The first clear X-ray focusing is confirmed. Its angular resolution is 4.1 arcmin in full width half maximum while it is at least 92 arcmin in half power width. The effective area is 19.0 mm$$^2$$2 which is $$\sim$$~5 times smaller than a model calculation. We discuss causes of the degraded angular resolution and effective area and also future improvements.