A system for testing optical transmitters including a testing unit, a sensor board, one or more support rails, and a driver is provided. The testing board includes sockets that each receive a substrate supporting a plurality of optical transmitters, and the sensor board includes optical receivers. The one or more support rails are attached to one of the testing board or the sensor board and are designed to engage the other of the testing board or the sensor board. The one or more support rails are configured to substantially align each of the optical receivers with a corresponding socket. The driver is in electrical communication with the optical transmitters and the one or more optical receivers such that the driver can apply a current input to at least, one of the optical transmitters and monitor a corresponding output parameter.