Table 2.

Comparison of performance of different types of detectors. The following detector specifications were used: reach-through SPAD: SPCM AQR-14 (Perkin Elmer Optoelectronics, Fremont, CA, USA); epitaxial SPAD: PDM 50CTC (Micro Photon Devices, Bolzano, IT); GaAsP PMT: H7422-40 (Hamamatsu Photonics, Bridgewater, NJ, USA); CCD: CoolSnap HQ (Photometrics, Tucson, AZ, USA), ICCD: I-Pentamax (Princeton Instruments, Trenton, NJ, USA); EMCCD: Cascade 512B (Photometrics)

	H33D		Single-Photon Counting Detectors			Imagers
	Gen I	Gen III	Reach-through SPAD	Epitaxial SPAD	GaAsP PMT	CCD	ICCD	EMCCD
Technology	Vacuum	Vacuum	Solid State	Solid State	Vacuum	Solid State	Vacuum + Solid State	Solid State
Photon Counting	+	+	+	+	+	−	−	−
Sensitive material	S20	GaAs	Si	Si	GaAsP	Si	GaAs	Si
QE (@ 600 nm)	4%	35-40%	70%	30%	40%	60%	45%	90%
Time Resolution	100 ps	250 ps	300 ps	50 ps	400 ps	100 ms†	60 ms†	34 ms†
Global Rate*	500 kHz	20 MHz	N/A	N/A	N/A	217 GHz	315 MHz	12 GHz
Local Rate*	10 kHz	100 kHz	10 MHz	10 MHz	10 MHz	150 kHz	1.2 kHz	46 kHz
Nb of Pixels	π 1282	π 2562	1	1	1	1392 ×1040	512 × 512	512 × 512
Pixel Size	100 μm	35 μm	170 μm	50 μm	5 mm	6.5 μm	15 μm	16 μm
Max Frame Rate‡	1 kHz	1 kHz	¼ frame/min	¼ frame/min	¼ frame/min	10 Hz	15 Hz	29 Hz

^*For imagers, the local count rate is replaced by the pixel well capacity divided by the maximum gain (electrons per photon) divided by the maximum frame rate. Using the minimum gain would allow obtaining higher count rates, but would result in worse single-molecule detection (lower SNR) because of the larger influence of the readout noise.

^†Better timing resolution (down to a few ms) can be achieved by limiting the acquisition to a small number of pixels, or by binning pixels. Notice also that ICCD’s can in some case be gated to obtain ~ 200 ps nanotime-resolution (see text).

^‡Frame rates for point detectors are calculated for a raster-scanned image of 512 × 512 pixels, and assuming a dwell-time of 1 ms/pixel.