The focus of expansion plays an important role in many vision applications such as three-dimensional reconstruction, range estimation, time-to-impact computation, and obstacle avoidance. Most current techniques are based on correspondence or on accurate flow estimation and are therefore considered computationally heavy. This paper presents an efficient technique to find the focus of expansion from optical flow. The technique utilizes a specially designed matched filter that does not require an exact estimation of the optical flow but rather can use a low-quality estimation of it. In addition, based on the location of the focus of expansion and its immediate neighborhood, the paper suggests a way to estimate the range to the focus of expansion. Based on the experimental results, the technique has proved to be both accurate and efficient.