PEN-TYPE DRUG INJECTION DEVICE AND OPTICAL DOSE VALUE DECODING SYSTEM WITH ADDITIONAL SENSOR TO DISTINGUISH BETWEEN DOSE DIALLING AND DOSE DELIVERY MODE

摘要

An optical decoding system comprising: a first optical sensor configured to be directed at a first rotatable component of a drug delivery device; a second optical sensor configured to be directed at a second rotatable component of a drug delivery device; and a processor configured to: receive signals from the first optical sensor, wherein the signals from the first optical sensor represent encoded dosage values present on the first rotatable component; receive signals from the second optical sensor, wherein the signals from the second optical sensor represent whether the second rotatable component is rotating or not; and to determine from the received signals whether the drug delivery device is in a drug dose dialling mode or a drug dose delivery mode.