Patent ID: 7794659

Claim:
An apparatus for measuring a signal emitted by the contents of each of a plurality of reaction receptacles comprising: a moving reaction receptacle carrier including a plurality of reaction receptacle stations, each of said reaction receptacle stations adapted to carry two or more reaction receptacles; a housing containing said reaction receptacles and said reaction receptacle carrier; two or more signal measuring devices, each said signal measuring device is constructed and arranged to measure the amount of a different optical signal emitted by the contents of a reaction receptacle placed in operative proximity to each signal measuring device, each signal measuring device being positioned with respect to said reaction receptacle carrier such that reaction receptacles carried on said reaction receptacle carrier are successively moved into operative proximity to each signal measuring device as said reaction receptacle carrier moves the reaction receptacles; and a signal measuring device transport mechanism located outside said housing and constructed and arranged to move said signal measuring devices with respect to said reaction receptacle carrier; wherein at least a portion of each of said signal measuring devices is located outside said housing, and each said signal measuring device is configured to measure the amount of an optical signal emitted by the contents of a reaction receptacle through an opening formed in said housing; wherein said reaction receptacle carrier is constructed and arranged to successively present said reaction receptacle stations in signal measuring positions in which one of the reaction receptacles carried in the reaction receptacle station is in operative proximity to one of said signal measuring devices, and said signal measuring device transport mechanism is constructed and arranged to move each said signal measuring device with respect to said reaction receptacle carrier to successively place each said signal measuring device into operative proximity to each of the reaction receptacles carried in the reaction receptacle station and moved into the signal measuring position corresponding to the signal measuring device.