In the last several decades, astronauts on space missions experienced a phenomenon known as light flashes. Results of experiments conducted, not only by crews aboard MIR and ISS, show that this phenomenon is a consequence of the interaction of cosmic rays with the human visual system. The results discussed in our paper were obtained by simulating the interactions of high-energy protons originating from cosmic rays with a simple human eye model. These simulations have been performed by two advanced Monte Carlo simulation packages - FLUKA and GEANT4 - configured for the same conditions. Presented yield functions for different secondary particles created inside the eye are products of the simulated interactions. Contribution of the Cherenkov photons was also taken into account. The article briefly discusses the possibility of the creation of light flashes by the observed secondary particles.