The "topography" beamline was planned from the very beginning of the ESRF project. Under the name of BL16 it belonged to the ‘second phase’ of construction of beamlines. The definition of the main purpose of the beamline, as well as preliminary ideas on its design, were given by a small group of colleagues for the "Red book" of the ESRF. This was refined by a first meeting of the concerned community, in Grenoble in the summer of 1990. A document, produced for the Management of the ESRF, resulted from this meeting [1]. It already contained, as a recommendation, the main specificities of the beamline :

  • i) the scientific case and
    ii) a wiggler source and a long (>100m) source-to-sample distance as means to achieve it, through the use of a wide and homogeneous beam for imaging.

The first 1990 Grenoble meeting was followed by a series of Conferences at the European level ("X-TOP" meetings: Marseille 92, Berlin 94, Palermo 96, Durham 98) of the same scientific community. The first of them showed an evolution of part of this community : reciprocal space mapping obtained by high resolution diffractometry was increasingly included as a tool for the investigation of strains and defects in crystals and layered materials. The implementation of this technique, in addition to diffraction topography, was proposed to, and approved by, the SAC in 1992 [2].

The "Topography" group was very lucky to be able to perform first tests at ID11, and to benefit, during the construction period of ID19, from the hospitality of Andreas Freund on the "Optics" beamline BM5. We learned a lot by testing the prototypes of the diffractometer, detector holder, … installed in the second hutch of BM5, and by performing a series of preliminary experiments [3, 4]. Two major facts substantially modified the initial ID19 scheme: the possibilities offered by the use of the coherence of the beam for imaging [5, 6], and the importance of three-dimensional (3D) images, initiated by the microtomographic investigation of bones [7].

The beamline ID19 entered into operation in the spring of 1996. The scientific results, which cover a wide variety of topics in condensed matter, can be estimated through the various reports on in-house research, and the list of publications, which follow this general presentation. The trends of this almost four year period confirm those identified during the preliminary work at BM5. In addition they point out :

  • 1) the importance of in-situ experiments (as a function of time, stress, temperature, electric or magnetic field, …) in what concerns diffraction imaging,
    2) the increasing fraction of the beamline time devoted to microtomography and phase imaging, and
    3) the emergence of a permanent industrial activity. The extension of ID19, which is described in more details later, takes into account these evolutions.