Photomultipliers

Critical Parameters

Parameter	Description	Typical Value (Fast PTM)
Rise Time (TR)	The time interval between the arrival of photon at the cathode and the arrival of the amplified pulse at the anode	0,05 (MCP) to 3 ns
Transit Time (TT)	The time interval between the arrival of photon at the cathode and the arrival of the amplified pulse at the anode	MCP:0,5 ns. PMT: 5-30 ns
Transit Time Spread (TTS)	Considered as the most important specification for time-resolved measurements; the timing variation due to the different geometric paths that the electrons can take from the cathode to the anode	MCP: 0,025 ns. PMT: 0,2-1,5 ns

Overview of different PMT's

Part ID	Type	Driving Voltage	Gain	Spectral Range (nm)	Spectral Peak (nm)	Dark Current (after 30 min)	Rise Time (ns)	Transit Time (TT)(ns)	Transit Time Spread (TTS) (ns)	Pricing
R1161	PMT - Head On	1000 V	1,0E+06	300 to 650	420	1-6 nA	2,5	27	2,8	x
R5505	PMT - Head On	1750 V	1,0E+06	300 to 1400	900	10 nA	3	23	1,5	x
R3478	PMT - Head On	1700 V	1,7E+06	300 to 650	420	6 nA	1,3	14	0,36	x
7400U-02	PMT - Head On	800 V	5,0E+05	300 to 850	500	2 nA	0,78	5,4	0,23	6404 SEK
7400-02	PMT - Head On	800 V	7,0E+05	300 to 850	420	0,2 nA	0,75	5,4	0,28	6404 SEK
R380952	MCP - PMT	3000 V	2,0E+05	160 to 650	400	2000/s	0,15	0,55	0,025	126,346 SEK
R5916U-52	MCP - PMT	3000 V	2,0E+05	160 to 650	400	0,5	0,18	1	0,09	148,643 SEK

So whats's up with the MCP's?

Microchannel Plate PMT, has plates containing numerous small holes, microchannels, which are lined with a secondary emissive dynode material. Electrons are amplified as they drop down the voltage gradients across the microchannel plate.

MCP-PMT shows the fastes time response due to the restricted range of electron paths and short electron travel distance.

Disadvantage is lower gain and photocurrent typ at 100 nA vs. 10-100uA for dyanode PMT