| abstract |
A photometer (30) and a test sample holder (50), with the holder having a light-blocking, black upper section (52, 54) and a light-transparent, lower section test sample vial (56), for use with the photometer (30). The photometer (30) includes an O-ring seal (75) at an input (40), to the light measurement sample chamber (100), so on insertion of the holder (50), with a test sample (53) to be detected in the test vial (56), the upper section (52, 56) blocks interfering light from the chamber (100). |