Filters, light interference wedge

Fig. 4. Schematic drawing of the details of the construction of the wedge interference filter spectrometer. J, injection port C, light-tight cover V, sample vial sample vial holder S, slit FH, filter housing F, wedge interference filter PT phototube PC, photocathode L, linkage to screw drive RF, RF shielded phototube housing.

For exceedingly weak chemiluminescent reactions it is possible to improve the light collection geometry at the expense of spectral resolution and to use a wedge interference filter spectrometer as shown in Fig. 4 (Hamman, Biggley and Seliger, 1979). 

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