Table 8.
Comparison of different light detectors.
| Standard Photo-diodes | Avalanche Photodiode s APD | Conventional Photo Multiplier Tubes (PMTs) | Micro-channel plate PMT ( MCP-PMTs ) | Si Photo-multipliers (SPM, SiPM) | |
|---|---|---|---|---|---|
|
| |||||
| Gain | None | Low gain (x10-300) | High Gain (106) | High Gain (106) Typical = 5 ×105 | High Gain (106) Much higher gains than APDs. Same region as PMTs. |
| Bias V | High (800V) | High (kV) | Low (30V) | ||
| Sensitivity | Typically < 1 A/W | 25 A/W @ 520 nm30 A/W @ 1,064 nm | 40,000 A/W @ 520 nm(SensL)[67]Sensitivity: 110 uA/lmAnode sens:500 A/lm (nominal);2,000 A/lm (max) | Very highCathodesensitivity>1,200 uA/lm (min), 1,500 (typical)(Burle)[62] | 60,000 A/W @ 520 nm (micro)130,000 A/W @520 nm (mini)1,000 A/W @ 1,064nm |
| Response to excess light | Some PIN damaged | Some APDs are damaged | Damage | Tolerant | |
| Area | Small | Small | Large diameters-e.g. 46mm.Arrays are impossible | Small (1×1 mm2)large areas up to 9mm2 available.Building larger arrays is possible. | |
| Rise/Fall Times -response | Trise = 0.1microseconds | Can be operated at 2,000 MHz. (therefore ns) | Rise time: 1 ns. | Faster thanPMTs.100 picoseconds | <5ns |
| Quantum Efficiencies | Higher than PMTs | Higher than PMTs | 20-30% at peak | >20% at peak | 40% @ 520 nm at peak |
| SNR (signal to noise) | Low | Low. | HighPMTs offer a higher gain, larger detection area and superior SNR compared to APDs | High –SNR to be similar, and in some cases better than PMTs. | |
| Other notes | Robust | Robust | Fragile, affected by magnetic, electromagnetic interference. | Excellent for pulsed light. | Robust |