Abstract: The neuromorphic visual system, which emulates biological visual mechanisms, demonstrates significant potential for highly efficient visual information processing. In this context, the development of an optical synaptic device capable of integrating light sensing, storage, and processing functions is of critical importance. However, current designs encounter performance limitations when balancing persistent light signal storage with dynamic regulation. To address this challenge, we propose and fabricate an optical synaptic device based on a composite of long-afterglow material and PDMS. Experimental results reveal that the device exhibits a transient brightness enhancement effect under ultraviolet pulse excitation, followed by a dual-stage decay with fast-to-slow kinetics after the cessation of stimulation. This behavior successfully mimics the dynamic transition from short-term to long-term memory in the biological visual system. Furthermore, the device demonstrates a PPF effect, with an enhancement ratio of 1.35 (A₂/A₁ = 1.35), and achieves nearly a threefold increase in light intensity (A₉/A₁ ≈ 3) under continuous stimulation by nine light pulses. The luminescent response of the device displays notable temperature dependence: as the temperature rises, the luminescence intensity initially increases by nearly 1.4 times before subsequently declining. These findings suggest that the long-afterglow material-based optical synaptic device has potential applications in non-volatile light information storage and dynamic processing, offering an innovative approach for advancing neuromorphic visual perception systems.