The FR-103TPM is a high resolution, interferometric  TPC (Two Photon Conductivity)                    

      autocorrelator for Multiphoton Microscopy. It can be introduced in the beampath

      without affecting the laser's direction and its NL detector can be placed anywhere

      within the optical set-up (e,g. at the location of the sample), to yield the

      laser pulsewidth at that position.