EasyTau 2

Fluorescence Spectrometer Control and Data Analysis Software

  • Data fitting / analysis software for set-ups based on PicoQuant TCSPC electronics
  • Combined software solution for data fitting / analysis and controlling the FluoTime 250 and 300 spectrometer
  • Wizard-guided measurements or full control with customized mode
  • Steady-state and global decay analysis with robust error analysis
  • Powerful scripting language for automation (local and remote)

The EasyTau 2 software package is the one-stop solution for both full hardware control of the FluoTime 250 and FluoTime 300 spectrometer as well as for interactive data analysis and fitting  It can also be used as a data analysis software for custom set-ups based on PicoQuant TCSPC electronics. The integrated analysis and fitting module supports a broad range of fluorescence spectroscopy applications, such as steady-state excitation and emission spectra, fluorescence or phosphorescence lifetimes, or anisotropy measurements. EasyTau 2 combines and improved on the features of the previously separate FluoFit and EasyTau software in a single, easy-to-use package..

Full hardware control

Perfroming anisotropy decay measurements with EasyTau 2The software package EasyTau 2 provides full control over all operational aspects of the FluoTime 300 fluorescence spectrometer in an intuitive and efficient way. A wide range of steady-state and time-resolved measurements can be carried out using a single graphical user interface. Supported methods include, amongst others, measurements of fluorescence or phosphorescence lifetimes, anisotropy, steady-state excitation and emission spectra, or Time-Resolved Emission Spectra (TRES). EasyTau 2 features specially designed applications wizards that guide a user through all optimization steps, enabling even novice users to perform such experiments. A customized measurement mode is provided for advanced users that desire full control over every instrumental parameter for every application.

The power of scripting

Complex applications, such as e.g., alternating between measuring time-resolved decays and steady-state spectra at different temperatures, can be easily automated by using the included scripting language. EasyTau 2 also provides an interface for remote execution of scripts, so that the automation can be extended to third-party accessories such as robotic autosamplers.

Data analysis at your fingertips

Analyzing luminescence decays with EasyTau 2The fitting and analysis module of the EasyTau 2 combines powerful, yet easy-to-use algorithms with efficient data management. It is not only capable of handling results of the FluoTime 250 and FluoTime 300 spectrometer, but can also import data from all PicoQuant TCSPC modules as well as ASCII files. The intuitive and interactive graphical user interface makes performing global decay as well as error analysis a breeze. All measured data is stored along with its related analysis results in a familiar file tree structure, that makes data dependencies visible at a glance. The module also comes with a powerful report generator to create presentation-ready plots or tables (as PDF or HTML files).

Fitting models and robust error analysis with a single GUI

Performing a Bootstrap error analysis with EasyTau 2EasyTau 2 supports both tail fitting and numerical reconvolution to account for the finite Instrument Response Function (IRF). Various models can be fitted to the decay data, including exponential decay (up to 5th order) or other distribution models, such as Gaussian, Lorentzian, or stretched exponential. All models support both global and batch mode fitting. The interactive graphical user interface simplifies setting starting parameters as well as fitting limits. Reduced chi-square, weighted residual and an autocorrelation trace are provided to assess the goodness of a fit. Additionally, a bootstrap error analysis can be carried out for every fit.

Current software version: 2.3

The latest version now supports Taiko PDL M1 and Prima as excitation sources as well as switching between different laser drivers at run time. There are also improvements in the measurement und analysis scripts. Note: the software is protected by a USB dongle and will not work without it. Please contact PicoQuant if you want to update EasyTau version 1.x or FluoFit to the latest version.

Course on time-resolved fluorescence

Logo Time-resolved Fluorescence CoursePicoQuant annually holds the European short course on "Principles and Applications of Time-resolved Fluorescence Spectroscopy". The course is intended for individuals wishing an in-depth introduction to the principles of fluorescence spectroscopy and its applications to the Life Sciences. The course is held in cooperation with Prof. J.R. Lakowicz from the Center of Fluorescence Spectroscopy (CFS) in Baltimore and consists of lectures as well as instrumentation and software hands-on training. For details see the course website.

FluoTime 300 hardware control
Included wizards Excitation and emission spectrum, time course excitation and emission spectrum, anisotropy excitation and emission spectrum, intensity time trace scan, temperature mapped emission spectra, excitation / emission mapping, quantum yield

Phosphorescence decay, fluorescence decay, time-resolved anisotropy, time course decay, time resolved emission scan
Operation modes Assisted mode using Wizards for standardized measurements
Customized mode with full control of all hardware parameters
Scripting mode for automation of routine measurements
Remote execution of scripts (extension of automation to 3rd party devices)
Basic data handling Arithmetic operations (addition, subtraction, multiplication, division), derivation, integration, normalization, smoothing, …
Fitting module
Exponential decay models Up to 5th order
Lifetime distributions Gaussian, Lorentzian, Stretched Exponential (with up to 5 peaks)
Anisotropy Up to 3rd order exponential decay model, tail fit of the anisotropy decay and anisotropy reconvolution
Decay parameters Amplitudes, lifetimes, distribution width, background
Anisotropy parameters G-factor, amplitude, background
Reconvolution parameters Background, time shift, scattered light contribution, pulse repetition rate
Nonlinear least squares fitting / MLE Marquardt-Levenberg, Monte Carlo, manual parameter variation
Correction for finite IRF Iterative reconvolution
Error test / assessment χ2, distribution and autocorrelation of weighted residuals
Error analysis Bootstrap
Global analysis / batch mode fitting For all fitting models, number of data sets only memory limited
User interface
Graphical user interface Windows based GUI
Display Linear or logarithmic scale, zoomable
Data import ASCII file or from Windows clipboard (HydraHarp 400, PicoHarp 300, TimeHarp 260, MultiHarp 150, NanoHarp 250)
Data formats
Number of channels Unlimited
Channel width Unlimited
Supported devices FluoTime 250 and FluoTime 300 spectrometer, HydraHarp 400, PicoHarp 300, TimeHarp 260, MultiHarp 150, NanoHarp 250 (binary or clipboard) and ASCII
Operation environment
Computer CPU: min. 2 GHz, RAM: min 2 GB
Display 1024 × 768 (or better)
Operating system Windows 8.1 or 10
Protection module USB

All Information given here is reliable to our best knowledge. However, no responsibility is assumed for possible inaccuracies or omissions. Specifications and external appearances are subject to change without notice.

The EasyTau 2 software can be used in applications where the fluorescence (luminescence) lifetime, determined from a single point measurement, is a key parameters, such as:

The following documents are available for download:

Latest 10 publications referencing FluoFit, FluoTime 300

The following list is an extract of 10 recent publications from our bibliography that either bear reference or are releated to this product in some way. Do you miss your publication? If yes, we will be happy to include it in our bibliography. Please send an e-mail to containing the appropriate citation. Thank you very much in advance for your kind co-operation.