Figure 4
From: Ice thickness monitoring for cryo-EM grids by interferometry imaging
Application to EM grids coated with samples. Examples after having applied our method for copper (a,b), carbon-coated copper (c), and gold (d) grids. While (a,b,c) were imaged using a 10 × magnification objective, (c) was measured at higher resolution using a 20 × objective. The individual grid squares are highlighted with colours according to the ice layer quality defined in this work by 5 classes: bad (class 0, in red), too thin (class 1, in white), optimal (class 2, in green), thicker (class 3, in bright green) and too thick (class 4, in red), respectively (colour legends indicated on the right). While the grids shown in (a) and (c) exhibit a nearly ideal ice behaviour for most of its grid squares (indicated by numerous green and bright-green classified grid squares; the squares in red in (c) were only partially imaged), the grid in (b) shows only regions with thicker ice (in orange), and the one displayed in (d) is an intermediate case with a mixture of class 2 and class 3 grid squares. Numbers indicate confidence of ANN. Scale bar 50 µm.
