Photomultipliers

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Critical Parameters

Parameter Description Typical Value (Fast PTM) H6780-02
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 0,78 ns (0,2 s settling time)
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


PMT Parameters.jpg

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 16 010 SEK
R3478 PMT - Head On 1700 V 1,7E+06 300 to 650 420 6 nA 1,3 14 0,36 3 837 SEK
7400U-02 PMT - Head On 800 V 5,0E+05 300 to 850 500 2 nA 0,78 5,4 0,23 6 404 SEK
R2083 PMT - Head On 3000 V 2,5E+06 300 to 650 420 100 nA 0,7 16 0,37 14 955 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
R3809-52 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
MCP-PMT.jpg