Solar parabolic trough collectors (PTC) are one of the mature technologies that have increased the share of solar energy in the power sector. Having a working temperature in the range of 200 to 500 °C, PTC systems can be integrated whether as a direct steam generator using water as the heat transfer fluid or with a Rankine cycle turbine by means of a heat exchanger and other heat transfer fluids such as air, molten salts, oils and nanofluid. In this research, a novel concept of a tube-bundle cavity receiver is investigated using optical simulations through SolTrace software. The obtained results proved that the tube-bundle cavity absorber will increase the average and the peak flux reaching the receiving area by near 100%. Then the optical modelling was validated for the parabolic trough solar collector of LS-2 and the results showed a very good agreement with the literature, concerning the optical criteria.