A method of mounting a fiber optic unit to a photosensor. The photosensor is mounted to a first carrier. A first end of the fiber optic unit is bonded to the photosensor to create a joint between the fiber optic unit and the photosensor. A second end of the fiber optic unit is mounted to a second carrier. The joint between the fiber optic unit and the photosensor is compressed. This compressing step strengthens the bond between the fiber optic unit and the photosensor.