ULTRA SOFT X-RAY MICROSCOPY 





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(a) high vacuum isolation gate 



(i) water-cooled demountable anode 



(c) accelerating grid 



(d) helical TUNGSTEN EMITTER 



e) charcoal trap 



Fig. 5. The schematic design of an ultrasoft x-ray source of monochromatic radiation in which 

 tungsten contamination of the target has been eliminated by placing the emitter below the anode. 



SAMPLE AREA 



ABSORPTION FOIL WEDSE 



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ROTATINS SECTOR WEDGE 



Rototlon 



RECORDING MATERIAL 



THIN WINDOW 

 (FILTER) 



Fig. 6. Illustrating the method used for generating an exposure wedge for the precise calibration of 

 a large-field microradiographic plate for quantitative analysis. 



source when the camera has been piunped microradiogram plate for an accurate ex- 

 down, posure wedge. Such a wedge, as shown in 

 In order to carry out precise quantitative Fig. 6, generated simultaneously with the 

 microradiographic analj^sis, it is necessary to sample exposure, permits an accurate cali- 

 have a sufficient area of uniform field on the bration of the emulsion, without the extreme 



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