Overview of Side-on Multialkali PMT
The R928P and its extension to the NIR region, R13456, are rugged and sensitive photomultiplier tubes (PMTs) that last for years. ISS provides compact housings designed for both photon counting and frequency-domain data acquisition; they are coupled to the instrument through a M28x1 threaded flange. An adapter for coupling the PMT housing to a 10 mm fiber bundle is available.
The housing includes the high voltage power supply operating up to 1,200 V and requires a ±15 V, DC voltage for operation. In photon counting mode of operation, the PMT housing operates at maximum voltage. In analog mode of operation, the voltage can be changed manually through an external potentiometer positioned on the housing; or, automatically, through the computer.
The frequency response of the housing is up to 700 MHz. In operation, the effective frequency response is determined by the PMT utilized for detection; selected PMTs Model R928 feature a frequency response up to 500 MHz. The radiofrequency signal is injected through a BNC jack located on the back panel of the PMT housing.
Room temperature and cooled housings are available. Cooling the photomultiplier tube, reduces the dark current and increases the dynamic range. ISS offers a cooled photomultiplier tube recommended for use in photon counting detection when a high instrument sensitivity is required. The housing is cooled by a thermoelectric element which allows the temperature to be set as low as -28 °C.
Product Specifications for Side-on Multialkali PMT
| ISS part no. | R928P | R13456 |
|---|---|---|
| Wavelength range (nm) | 185 - 900 | 185 - 980 |
| Peak sensitivity wavelength | 400 | 400 |
| Quantum efficiency | 24% @ 400 nm | 12% @ 800 nm |
| Dark counts (cooled version) (c/s @ T=30) | < 100 | < 150 |
| Effective area diameter (mm) | 8 x 24 | 8 x 24 |
| Transit Time Spread (FWHM, typ. Value) | 1,200 ps | 1,400 ps |
| Rise time (ns) | 2,200 | |
| Max Count rate | > 10 MHz | |
Signal Input
Supply Current
- 132 mA of +15 V, 27 mA of -15V
Supply Voltage
- ±15 V
Connector
- 5-PIN DIN
Control
- Manual or through a DAC
RF Input
Max Amplitude
- +13 V pp
Connector
- BNC
Signal Output
Polarity
- Negative
Frequency Response
- DC - 500 MHz
Connector
- BNC
Mechanical
Coupling Flange
- M28 x 1
Temperature Control (for cooled housing only)
- Through a Peltier element down to -28 °C
Dimensions
Room PMT housing
- 2.5 kg
Cooled PMT housing
- 4.8 kg
Weight (kg)
Room Temperature PMT Housing
- 2.5
Cooled PMT Housing
- 4.8
