2944
Data on the line spread function ( LSF ) were obtained from the image of a 0 . 2 mm wide slit between tungsten blocks that were positioned at the isocentre in front of a polystyrene phantom .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
 Entities:  
Answer:
 None