Figure 1. Ahmed Hassan Zewail 1946-2016
Figure 2. Ibn al-Haytham's Camera Obscura. The concept of the Camera Obscuraas perceived a thousand years ago by Ibn al-Haytham, who coined the Arabic term. Note the formation of the inverted image through a ray diagram. Illustration of theCamera Obscura in 1001 Inventions: Muslim Heritage in Our World (chief editor Salim Al-Hassani), Manchester: FSTC, 2008, 2nd Edition, ISBN: 9780955242618, p. 29. See also The Year of Ibn al-Haytham (published 15/02/2011) and Ahmed H. Zewail,Micrographia of the twenty-first century: from Camera Obscura to 4D microscopy(The Royal Society, 2010).
Figure 3. 4D electron imaging in real, Fourier and energy spaces. The conceptual design of Caltech’s UEM-2 is presented on the right; a single-electron trajectory is depicted within the UEM. The atomic-scale (femtosecond) temporal resolution characteristic of the apparatus allows for the visualization of dynamical processes in real time. Shown on the left are typical UEM frames of real-space images and diffraction patterns, together with three-dimensional maps of femtosecond-resolved electron-energy-loss spectra (FEELS). For a recent review, seeShorokhov & Zewail (2009).
Figure 4. Microscopy time line, from camera obscura to three-dimensional electron microscopes. 4D ultrafast electron microscopy and diffraction were developed a decade ago. The top inset shows the frontispiece to Hooke’s (1665) Micrographia published by the Royal Society of London. In the frontispiece to Hevelius’s Selenographia (bottom inset), Ibn al-Haytham representsRatione (the use of reason) with his geometrical proof and Galileo represents Sensu (the use of the senses) with his telescope. The two scientists hold the book’s title page between them, suggesting a harmony between the methods (Sabra 2003; Steffens 2006; Zewail & Thomas 2009).