the diffuser 50 could have other shapes as well that improve light distribution additionally a light scattering filler such as glass microballoons titanium iv oxide etc may be incorporated into diffuser 50 to improve light distribution similar to the underfill layer discussed above fig1 a and 10b depict pictures of a flip chip led with diffuser in non energized fig1 a and energized states fig1 b the diffuser of the present invention substantially increases the far field emission pattern of the light from the led die and results in a more symmetrical distribution of light the diffuser may be formed directly on flip chip led 30 by transferring a predetermined amount of the polymer filler mixture to the upper surface of flip chip led 30 using a pipette etc or alternatively a pre formed diffuser may be attached to the upper surface of flip chip led 30 fig1 presents a flip chip led mounted within a sensor in accordance with an embodiment of the present invention in this embodiment sensor 60 is a sensor to monitor in vivo analytes of interest within a patient such as for example glucose levels flip chip led die 30 is mounted to the top surface of printed circuit board substrate 62 in accordance with the techniques described above photodetector 64 and supporting electronics 66 are also mounted on printed circuit board 20 preferably in accordance with the techniques described above.