Operation and Software Features (Current version: 3.0)

The TimeHarp 100 can be used in various operation modes: 

Integration mode

Measurement of the accumulated events as a function of time, manually started, stopped manually or after overflow or collection time. 32 curves with up to 4096 time channels.  

Oscilloscope mode

Repetitive measurement and on-line display, very useful for optical alignment. 

Operation mode f(t,T)

Continuously recording histograms without time gaps straight to disk. Acquisition time interval per histogram programmable from 1 ms to 1 s. 

Externally clocked continuous mode (imaging, scanning)

A scanner or other external hardware provides a pixel clock signal to switch to the next histogram in real-time. Data is recorded straight to disk, allowing an unlimited number of pixels. 

Time-Tagged Time-Resolved mode (TTTR) Available as an option

Continuously recording photons without onboard histogramming straight to disk. Together with the channel number the arrival time of each photon is recorded for ultimate flexibility in offline data analysis, e.g. in single molecule detection and Burst Integrated Fluorescence Lifetime (BIFL) measurement. 

Software Overview

The TimeHarp 100 software allows the control of all measurement parameters provided by the TimeHarp 100 board. Both input triggers are programmable for a variety of signal types. All functions of the system are controlled by a 32-bit Windows based software interface. The software provides functions such as the setting of measurement parameters, display of measurement results, loading and saving of measurement parameters and measurement curves. Important measurement characteristics such as count rate, count maximum and position, as well as histogram width (FWHM) are displayed continuously. An automatic setup function adjusts the system to an initial optimum display range setting for the histogram. A comprehensive online help function shortens the user's learning curve. A driver library (DLL) for custom Windows program development is available to build your own applications e.g. in Labview , C++, Delphi or Visual Basic . Demo code is provided for an easy start.

The software features an improved data visualization and printing, running on all 32 bit Windows platforms incl. XP. Full integration with Windows device management. Preservation of individual settings on multi-user platforms. Improved continuous mode data throughput on Windows NT, 2000 and XP.

The figure below shows measurement results from a fluorescent dye obtained with the TimeHarp 100. For these measurements we used the PDL 800-B with a PLS 450 LED head for excitation and the fluorescence was detected using the PMA 182.

A typical fluorescence decay curve taken with the TimeHarp 100

The control panel of the TimeHarp 100

To learn more about Time-Correlated Single Photon Counting and the use of the TimeHarp 100, please request our Tech Note on TCSPC.

last updated 21.2.2002