Time Correlated Single Photon Counting Systems
Becker & Hickl develop and manufacture innovative control and measurement systems and complete Time Correlated Single Photon Counting Systems. Photonic Solutions are the exclusive UK distributor for this leading manufacturer of TCSPC systems. No other manufacturer of TCSPC systems displays both cutting edge speed and detectability along with a unique ability to customise systems specificaly around customers photon counting requirements. Becker & Hickl also offer a range of picosecond diodes lasers and ultra-fast photomultipliers, all of which are complementary to their photon counter cards.
The Principle of Time Correlated Single Photon Counting (TCSPC)
Time Correlated Single Photon Counting, or TCSPC as it is commonly known, is a technique to record low level light signals with picosecond time resolution. TCSPC is a well established technique for fluorescence lifetime measurements, offering ultra-high time resolution with lifetimes measurable down to picoseconds and ultra-high sensitivity down to the single photon level. TCSPC is also commonly used is these applications:
- Ultra-Fast Recording of Optical Waveforms
- Fluorescence Lifetime Measurements
- Detection and Identification of Single Molecules
- DNA Sequencing
- Optical Tomography
- Fluorescence Lifetime Imaging
The principle of time correlated single photon counting is the detection of single photons of a periodical light signal, the measurement of the detection times of the individual photons and the reconstruction of the waveform from the individual time measurements. Time correlated single photon counting is a statistical method and a high repetitive light source is needed to accumulate a sufficient number of photon events for a required statistical data precision. The accuracy of the time measurement in TCSPC is not limited by the width of the detector impulse response. For the TCSPC method only the timing accuracy in the detection channel is essential. This accuracy is determined by the transit time spread of the single photon pulses in the detector and the trigger accuracy in the electronic system. The timing accuracy can be up to 10 times better than the half width of the detector impulse response.