Figure 2.
(a) The protein crystal (yellow cube) is bathed in the humidified air stream (blue) with constant conditions (relative humidity rh0, gas temperature T 0). The infrared beam (red) strikes the protein crystal. The laser optic is mounted on an xyz micromanipulator. The dimension changes of the crystal are detected optically by a video system (stereo microscope with attached CCD camera; optical path in yellow). An IR filter protects the video system; a cabinet shields the laboratory (see the text for explanations). (b) The inside of the laser cabinet. The main components are: FMS head (1) with tubing for temperature control (2) and transport of the humidified gas stream (3), loop holder (4) and capillary holder (5) mounted on xyz translation stages, laser optic (6), optic of the stereo microscope (video system) (7) and light source (8).