Abstract: A TLD card reader comprising infeed and outfeed carousels for sequentially indexing cartridge holders for stacks of TLD cards to infeed and outfeed stations, and a shuttle transport for sequentially transferring TLD cards from the infeed station to a card read station and then to the outfeed station. At the read station plural photomultiplier tubes are mounted in opposition to respective hot fingers which are independently adjustable along three axes as well as independently biased for engagement with respective TL elements in a TLD card. For photomultiplier tube calibration a shuttle assembly is operable to move reference lights into the path of the shuttle transport for alignment with respective photomultiplier tubes. A light seal of star-like cross-section also is provided to seal the shuttle passageway at the read station.