National Physical Laboratory

Ultrafast Waveforms

The Ultrafast group at NPL provides measurement facilities for characterising fast electrical and optical pulses as well as calibration services for fast pulse generators and high-bandwidth oscilloscopes.

Close-up of the NPL Electro-optic sampling (EOS) system
Close-up of the NPL Electro-optic sampling
(EOS) system

Rapid advances in technology are driving demand for high-bandwidth instrumentation, systems, sources and circuits, leading to a consequent increase in calibration and traceability requirements. With over 20 years experience, the Ultrafast Measurements section provides measurement solutions in communications, broadcasting and many areas of electronics, optics and computing where there are demanding requirements. Examples of what we can offer include the characterisation of short electrical and optical pulses, new types of test instrumentation, and the calibration of fast electrical pulse generators and high-bandwidth oscilloscopes. Carried out by highly skilled staff members our services use fully traceable techniques.

Traceable Calibration Services

  • Risetime and frequency calibration of real-time oscilloscopes above 1 GHz
  • Phase and magnitude measurement of optical receivers over 10 GHz
  • Measurement of impulse response for fast photodiodes and optical receivers
  • Deconvolution and jitter analysis
  • Frequency domain measurements up to 67 GHz
  • Risetime of electrical power meters

Current Research Areas

  • Femtosecond pulse shaping and measurement
  • Optical Parametric Oscillators (OPO)
  • Quantum coherent control

Special Facilities

NPL has several facilities including femtosecond electro-optic sampling systems, femtosecond photoconductive pulse generators, a range of commercially-available oscilloscopes and photodiodes, and numerous fast electrical and optoelectronic devices. Some of these facilities are available for supervised third party use.

Summary of Calibration Services traceable to UK National Standards

For more details, please contact

UKAS Accredited Services (to ISO 17025)

  Range UKAS uncertainty Accreditation*
Sampling oscilloscope risetime 5 ps - 50 ps
50 ps - 1 ns
1.3 ps
0.5% + 3 ps
Real-time oscilloscope risetime 300 ps - 10 ns 0.2% + 20 ps
Pulse generator risetime 11 ps - 60 ps
60 ps -10 ns
0.9 ps
0.5% + 1.4 ps
Pulse amplitude 50 mV – 800 mV
800 mV – 1V
Pulse settling - 0.05%
Pulse pre/over/undershoot - 0.1%

*UKAS accredited uncertainties quoted for a probability of not less than 95%. These are the best normally achievable - actual values are dependent on the particular instrument and the shape of the instrument response waveform.

NPL Custom Pulse Services

Instrument to be calibrated Specification Example measurement instrument
Pulse generator < 11 ps PSPL 4015D
Electrical oscilloscope sampling head < 5 ps (> 70 GHz) Agilent 86116C
Optical sampling modules Various Tektronix SD42
Fast photodiodes Various wavelengths and bandwidths Picometrix PX-D7
Real time digitising oscilloscopes < 300 ps (> 1 GHz) LeCroy Wavemaster 8600A


Customer Services tel: +44 20 8943 6796

Last Updated: 2 Sep 2014
Created: 12 Jun 2007


Please note that the information will not be divulged to third parties, or used without your permission