Described herein is a light directing assembly for use in an object analysis system. The light directing assembly includes a plurality of optical relay assemblies. Each optical relay assembly includes at least one optical element configured to relay an interrogation beam from a light transmission system to an object and relay a return beam from the object to the light transmission system, the return beam being generated by reflection or back scattering of the interrogation beam by the object. Each optical relay assembly defines an interrogation angle at which the interrogation beam relayed by the optical relay assembly reaches the object, and an optical path length being the distance from the light transmission system to the object travelled by an interrogation beam via the optical relay assembly. The plurality of optical relay assemblies are further configured such that the optical path length for a given optical relay assembly has a predefined relationship with the optical path lengths of the other optical relay assemblies.