Luminescence measurements enjoy superior signal to blank ratios because they are made by detecting photons emitted from the sample with no excitation source. If your microplate reader has low-noise detection electronics coupled with a high quality PMT and proper optical system then sub-attomolar detection levels can be reached with some assays. BMG LABTECH microplate readers have exceptional luminescence capabilities. In fact, to take advantage of luminescence assays, BMG LABTECH has created an internal system that is solely dedicated to luminescence within the PHERAstar Plus and PHERAstar FS as well as the OPTIMA and Omega Series including the FLUOstar, POLARstar and LUMIstar microplate readers.
BMG LABTECH has also designed specific optics for luminescence that increase the signal in various plate formats (96, 384, or 1536). This allows for an uncompromised signal regardless of your plate format.
For more information on BMG LABTECH's Dedicated Luminescence feature, see: http://www.bmglabtech.com/technology/dedicated-luminescence.cfm