Stroboscopic effects

Any risk to occupants from stroboscopic effects of blade movements ... 

L. Woste Prof. Neusser, you are able to select specific rotational states at very high specific Rydberg state quantum numbers n. So your orbiting electron becomes very slow, even slower than the molecular rotation. Do you see any chance to bring both into phase, causing stroboscopic effects ... 

Sometimes, the autoionized lines for very large values of n near the ionization threshold present a regular pattern characterized by the appearance of fringes . This phenomenon has been attributed to a stroboscopic effect between the periodic orbital motion of the Rydberg electron and that of the ion rotation (in Na2, Labastie, et al, 1984, in Li2, Schwarz, et al., 1988) and an interference effect resulting from the relative phases of the 1-mixing matrix elements and transition moments (in NO, Fredin, et al., 1987), or an effect of finite resolution (in HC1, Drescher, et al., 1993). 

Fluorescent lamps should be chosen and located carefully where they illuminate rotating shafts, so as to avoid a stroboscopic effect that shows the shaft to appear stationary even though it is in fact rotating at a high speed. 

The difficult task of expressing our everyday experiences of color matching often cannot be adequately defined in a color space. Extended light sources, flicker, stroboscopic effects, variable contrast backgrounds and surrounds, matte surfaces, and polished top layers such as a leaf (107) and others cannot be properly defined mathematically. Calculations that involve such parameters are only approximations of the situations they represent. Try to imagine how dull a scene would be if you only perceived instrument measured color information. 

Perception is the way in which people interpret the environment or the way in which a person believes or understands a situation. In health and safety, the perception of hazards is an important concern. Many accidents occur because people do not perceive that there is a risk. There are many common examples of this, including the use of personal protective equipment (such as hard hats) and guards on drilling machines and the washing of hands before meals. It is important to understand that when perception leads to an increased health and safety risk, it is not always caused by a conscious decision of the individual concerned. The stroboscopic effect caused by the rotation of a drill at certain speeds under fluorescent lighting will make the drill appear stationary. It is a well-known phenomenon, especially among illusionists, that people will often see what they expect to see rather than reality. Routine or repetitive tasks will reduce attention levels leading to the possibility of accidents. 

Discharge lighting may also cause a stroboscopic effect where rotating or reciprocating machinery is being used. This effect causes rotating machinery to appear stationary, and we will consider the elimination of this dangerous effect next. 

When only a single-phase supply is available, adjacent fluorescent tubes in twin fittings may be connected to a lead-lag circuit, as illustrated in Fig. 3.58. This is one lamp connected in series with a choke and the other in series with a choke and capacitor, which causes the currents in the two lamps to differ by between 120 and 180 degrees. The lamps flicker out of phase, producing a more uniform level of illumination which eliminates the stroboscopic effect, as shown in Fig. 3.59. 

Briefly describe what we mean by the stroboscopic effect when considering a lighting scheme for an industrial environment. 

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