Light self mirroring

Fig. 26. Block diagram of the optics of the triangle common-path interferometer Fourier transform spectrometer S, light source BS, beam splitter M1, M2,M 3, plane mirrors r, lens d, self-scanning photodiode array. [Redrawn from Okamoto et al. (139) with permission.]...

While familiarisation with the area to be visited is important, an essential part of the risk assessment procedure, that is often overlooked, is familiarisation with the mode of transport to be used. If this is a self-drive minibus, prior to the journey, a check should be carried out on basic safety features such as tyres, lights, windscreen washers/wipers, brakes, availability of first aid kit and fire extinguisher, fluid levels, doors (operate freely and close securely) and warning instruments. Driver effectiveness and fatigue is also influenced by poor driving position and conditions so, before setting off the driver should adjust the seat, the mirrors and check that they can reach all the essential controls. 

When the laser is fired, the frequencies with the highest intensities are stimulated more than other frequencies. The laser light is therefore even sharper than the normal E A spectral line. The narrowing is, in this case, a self-sharpening property. This gives a possibility to tune the laser using mirrors. 

Deflection detection schemes have been developed that use self-sensing piezoresistive cantilevers [104] or optical interferometry [105, 106]. But in nearly all practical systems cantilever deflection is measured with an optical lever system [107], as shown in Fig. 3.22. A small spot of laser light is reflected from the back of the cantilever and the reflected light is directed to an adjustable mirror. This in turn reflects the light onto a position-sensitive detector, a four-quadrant photo diode, shown schematically in Fig. 3.23. 

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