This paper addresses the collision detection problem in population protocols. The network consists of state machines called agents. At each time step, exactly one pair of agents is chosen uniformly at random to interact, updating their states. The collision detection problem assumes that each agent starts with an input integer between 1 and n , where n is the number of agents, and requires the agents to determine whether there are any duplicate input values among them. Specifically, the goal is for all agents to output false if all input values are distinct, and true otherwise. This paper presents an algorithm that solves this problem in sublinear parallel time, both with high probability and in expectation, using only a polynomial number of states, thereby answering one of the open questions raised by Burman, Chen, Chen, Doty, Nowak, Severson, and Xu [PODC 2021].