  The minimum-time path for intercepting a moving target with a prescribed
impact angle is studied in the paper. The candidate paths from Pontryagin's
maximum principle are analyzed, so that each candidate is related to a zero of
a real-valued function. It is found that the real-valued functions or their
first-order derivatives can be converted to polynomials of at most fourth
degree. As a result, each canidate path can be computed within a constant time
by embedding a standard polynomial solver into the typical bisection method.
The control strategy along the shortest candidate eventually gives rise to the
time-optimal guidance law. Finally, the developments of the paper is
illustrated and verified by three numerical examples.
