Autocorrelator Our Autocorrelators At a Glance

APE autocorrelators are used to measure the pulse duration of femtosecond and picosecond laser systems. The technology is based on either Second Harmonic Generation (SHG) detection or Two Photon Absorption (TPA) detection principle.

The pulse duration, also called pulse width, of a laser beam source is defined as the interwall between the two points in time at which the instantaneous power of the pulse reaches 50% of the peak power for the first and last time.

  • Wide choice of optics and detector sets (PMT, PD, or TPA)
  • Ready to use software and USB interface
  • Wide wavelength range from 200 nm to 12 μm
  • Wide range of pulse widths from < 10 fs to 400 ps
  • Compact footprint with the Mini PD and Mini TPA line
  • NIST traceable calibration
  • TCP/IP remote control with standardized command set for easy programming

PMT, PD, or TPA: For pulse measurement with extreme sensitivity* and low pulse energy, we recommend our photomultiplier (PMT) detector. Spectrally enhanced photodiodes (PD, TPA), on the other hand, are the ideal choice for measurements requiring sensitivities of a few mW2.

* Measured sensitivity including Optics Set, defined as average power times peak power of the incident pulses

  • Photodiode Detector (PD): Standard sensitivity up to 1 W2*
  • Photomultiplier (PMT): Highest sensitivity up to 10-6 W2*
  • Two Photon Absorption (TPA): High sensitivity up to 10-2 W2*

All APE Autocorrelators with NIST Tracable Calibration

Laboratories and manufacturers are often faced with systematically establishing an unbroken chain of calibrations to specified references. All APE autocorrelator models are calibrated to a traceable standard in accordance with NIST (U.S. National Institute of Standards and Technology) measurement traceability specifications. A printed and signed calibration certificate is provided with each instrument.

Collinear and Non-Collinear Measurements

Both the pulseCheck and Mini PD products support fast switching between collinear and non-collinear measurement modes. Collinear, often referred to as interferometric autocorrelation or fringe-resolved mode, provides additional qualitative information about the phase, the chirp and central wavelength of the pulse. In contrast, noncollinear mode, also known as intensity autocorrelation, provides a background-free  autocorrelation with a high dynamic range. A „hybrid“ of these two modes, collinear intensity autocorrelation, is realized with the Mini TPA and TPA Optics Sets for the pulseCheck.

Acquisition Software and TCP/IP Included

All models come with an easy to use data acquisition software, allowing for real-time data display. Furthermore, the TCP/IP-based standard  software interface by APE makes it straight forward to set up remote control. This allows you, for example, to design your own automated measurement routines. Simply use our protocol templates for rapid configuration with familiar programming languages, including C++, C#, LabVIEW, Python, Matlab, and Ruby.

Easy-to-operate through Automatic Phase Matching

Phase-sensitive and nonlinear processes, such as those associated with autocorrelators, require phase matching to ensure a highly efficient second harmonic generation. This phase matching is performed fully automatically for each wavelength range by APE’s pulseCheck. Full automation thus leads to precise and fast operation of the autocorrelator without the need for manual adjustment.

Our TPA detector-based autocorrelators are even easier to operate as they offer completely tuning-free operation over the entire wavelength range.