LIGHT PHOTON DETECTING APPARATUS AND A FILTER DELIVERY AND/OR COLLECTION SYSTEM THEREFOR

摘要

A filter delivery and/or collection system for use with light photon detecting apparatus, comptises an upstanding tube (10) for receiving filter paper (13) each held in an individual holder (14) and two toothed wheels (12) angularly moveable about horizontal or substantially horizontal axes to deliver filter papers to a surface (11) below the tube or to receive filter paper and retain them in the tube. Light photon detecting apparatus including filter paper delivery and/or collection systems as described is also disclosed.