Collimated Holes

Fig. 3.10. Reaction cell. 1 - Atom gun 2 - Thermostate 3 - Metal evaporator 4 - Pt/Pt-Rh thermocouple 5/7 - Collimation holes (diameter 3 mm) 8 -Shutter 9 - ZnO semiconductor sensor 10 - Mobile quartz weight 11 - Platinum contacts terminals 12 - Vitrificated iron bars controlled by a magnet 13 -Quartz guides...

Fig. 3.12. Reaction cell. 1 - the evaporator 2 - thermocouple 3 - beam splitter 4 - semiconductor sensor (ZnO) 5 - collimating holes 6 - atom beam shutter...

Table 10.1. Beam formation data for carbon dioxide flowing through a collimated-hole structure and observed at a distance of 40.6 cm. From [GWa60, Zan66].

The experimental uncertainty in measuring d is proportional to that of measuring the distances between pairs of fines and is approximately constant over tfie film unless fines in the back-reflection region are unduly faint or broad. However, even if the uncertainty of measurement is a little larger in the back-reflection region, the effect is ordinarily far outweighed by the cot d factor. In fact lines very close to the collimator hole should always... 

A precision transparent sieve with 2% tolerance, introduced by Collimated Holes Inc., was tested as a simple alternative to straightforward Coulter counting and gave good, reproducible results when used in combination with a specially designed filter holder to reduce contamination. This sieve has an additional advantage in that it can be examined under a microscope to determine the nature of the oversize particles. 

Figure 6 fVinehwiess system for resonance spectrometry o/F i j atoms. B, buffer chanAer C, collimated hole structures, two of which were mounted on specially fabricated glass discs, D K, inlet to lamp L M,M, differential manometers R, section of flow tube S, spectrometer slit, sealed via an O-riqg seal to the silica apparatus V, vacuum spectrometer (After ref. 24)... 

Recently some very precise filters made from a bundle of fibres in a glass matrix has been developed by Collimated Holes Incorporated [54]. To make these filters a bundle of fiber optics is assembled in a glass matrix with the core of a fiber perpendicular to the surface of the matrix. The assembled plate is then treated with a fluid to dissolve the central core of the fibre optics which are chemically different from the glass matrix. The resultant porous surface has very accurate holes for filtration purposes. 

As mentioned briefly in the first chapter when we considered the filtration of aerosol samples, a recent innovation in the construction of sieves using a matrix of fiberoptic elements has been described for the construction of sieves made of glass. Information on these sieves are available from Collimated Holes Incorporated [29]. 

Collimated Holes Incorporated, 460 Divisions Street, Campbell, California, 95008. 

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