  We show that a weak projective measurement of photon arrival time can be
realized by controllable two photon interferences with photons from short-time
reference pulses at a polarization beam splitter. The weak value of the
projector on the arrival time defined by the reference pulse can be obtained
from the coincidence rates conditioned by a specific output measurement. If the
weak measurement is followed by a measurement of frequency, the coincidence
counts reveal the complete temporal coherence of the single photon
wavefunction. Significantly, the weak values of the input state can also be
obtained at higher measurement strengths, so that correlations between weak
measurements on separate photons can be observed and evaluated without
difficulty. The method can thus be used to directly observe the non-classical
statistics of time-energy entangled photons.
