FEATURES OF VIDEO MICROSCOPE Designed to handle crystals down to 5 µm size Crystals from 5 to 200 µm size can be REMOTELY mounted, centered on the rotary motion axis and aligned with the beam. A high resolution video-microscope is used to view both the sample and the beam size and shape. The beam position can be checked at any time on a mouse click, even when a sample is mounted. High resolution with viewing coaxial to the beam The video-microscope is used to view the sample and the beam display scintillator. Because the camera looks in the direction of the beam, the sample can be aligned with the beam WITHOUT PARALLAX ERROR. - Sub-micron resolution, diffraction limited objective lens - High resolution 3CCD colour camera - Motorized zoom (X1 to X10; field 1.6 x 2.1 mm down to 0,16 x 0,21 mm) - Condenser lighting with polarizer - Motorized analyzer

Beam viewing scintillator The scintillator is a 3 mm3 fluorescent single crystal that can be set in the beam, at the exact position of the sample. The beam can be displayed at any time even while a sample is mounted (In this case the sample is slightly shifted away from the scintillator). The scintillator allows the user to weigh up the beam shape, quality and position. The resolution is only limited by the video-microscope. Low X-ray background A large amount of the beam path is shielded by molybdenum tubes to trim down the air scattering. A capillary/aperture unit is set just after the beam definition aperture. The free beam path in the air is then shortened to the distance between the cleaning aperture (set at the end of the capillary) and the beamstop (typically 10 mm). The capillary/aperture unit is mounted on a small support that is held by magnets . Alignment features described in the beam definition aperture are available. PC Controlled Standalone instrument The electronics is packaged in a 19″ 9U rack and installed near the micro-diffractometer. The rack is connected to a Window NT PC by two optical fibres. A video cable links the video-microscope to the PC frame grabber card. The control program is written in Visual Basic. A device server allows some devices to be controlled by a host computer. The Installation of the micro-diffractometer is easy and fast, usually one day is an adequate amount of to set and align the instrument.

Remote control Device Server As soon as the remote phase is selected, the GUI is locked out, and some devices like the PHI axis can be controlled by a host computer. Basic motion commands and high level commands like “angular scans with shutter control” are then available. Compatible with future automatic sample feeding systems An automatic sample changer for prefrozen sample is under development. It will be integrated as soon it will be obtainable. New Version A lot of features of the micro-diffractometer have been highly appreciated by the users. A version designed for more general use is under development. It will accept larger detectors (up to 30 x 30 cm overall size) with a minimum sample to detector distance of 5 cm. It will be compatible with experiments (Adjunction of a fluorescence detector) and can be provided with an automatic sample changer for pre-frozen samples.