Strong coupling between whispering gallery modes (WGMs) is studied in polystyrene bispheres by using spatially
resolved spectroscopy. The supermonodispersive pairs of spheres (size deviation <0.03%) were selected using their
uncoupled WGM peaks' positions. By using novel geometries of capturing light by the imaging spectrometer we
observed clear spectral signatures of strong coupling between WGMs for bispheres with mean sizes from 2.9 to 10 μm.
In a special geometry with the collection of light along the axis of bisphere and with the slit of the spectrometer oriented
perpendicular to the substrate we observed unusual and characteristic kites in the spectral images of such photonic
molecules. We showed that such kites allow unambiguous relating of the split components (antibonding and bonding
modes) in the spectral image to their WGM eigenstates in the uncoupled cavities. In many cases such kites simplify the
interpretation of the dense spectral images of bispheres. Using various geometries of the experiments we quantified the
dependence of coupling constant on the sizes of spheres for maximally coupled fundamental modes located in the
equatorial planes of spheres on the substrate. The results show the feasibility of achieving a coherent WGM-based
optical transport in microsphere resonator circuits.