High resolution synchrotron radiation has been used to study the photo-accessible 1P° doubly excited states converging on the (N=2) ionisation threshold of Helium. The doubly excited states are observed via their fluorescent decay products, namely metastable atoms and Vacuum Ultra-Violet photons. The lowest members of all three photo-accessible 1P° Rydberg series of doubly excited states, the (sp,2n+)1P°, (sp,2n-)1P° and (2p,nd) 1P° series, have been resolved, and trends in the observed intensities are compared with theoretical calculations. The breakdown of the LS coupling scheme is suggested as an interpretation for the rapid increase in metastable atom yield close to the He+(N=2) ionisation threshold. Recent state of the art theoretical calculations show that quantum numbers L and S are invalid for the description of doubly excited states in this energy region due to spin orbit effects. This allows doubly excited states to decay to the (1s2s)3Se metastable state causing the observed increase. A lower limit of 3.3 mueV for the energy width of the (2p,3d)1P° state was also determined by utilizing the pulsed nature of synchrotron radiation. This width is typically predicted to be more than two orders of magnitiide smaller than the resolution available at current synchrotron radiation sources. The measurement was made in the time domain by single photon counting and is the first experimental determination for the width of any state in this series. Comparison of the experimental limit is made with a number of theoretical calculations.