H7421_15 Datasheet, PDF (1/4 Pages) Hamamatsu Corporation – Metal package PMT with Cooler

Metal package PMT with Cooler
Photon Counting Head H7421 Series
The H7421 series is a photon counting head device containing a metal pack-
age photomultiplier tube having a GaAsP/GaAs photocathode and a thermo-
electric cooler. The thermoelectric cooler reduces thermal noise generated
from the photocathode which also offers a high quantum efficiency, allowing
measurement to be made with a good S/N ratio even at very low light levels.
The H7421-40 has high sensitivity on wavelength from 300 nm to 720 nm.
The H7421-50 is sensitive over a wide spectral range from 380 nm to 890 nm.
The photomultiplier tube is maintained at a constant temperature by monitor-
ing the output from a thermistor installed near the photomultiplier tube and
regulating the current to the thermoelectric cooler.
Heatsink with fan (A7423) sold separately
Product Variations
Type No. Spectral Response
Features
H7421-40
300 nm to 720 nm GaAsP photocathode, QE 40 % at peak wavelength
H7421-50
380 nm to 890 nm GaAs photocathode, QE 12 % at peak wavelength
This product can't be used at vacuum environment or reduced pressure environment.
Specifications
Parameter
H7421-40
H7421-50
Unit
Input Voltage
+4.5 to +5.5
V
Max. Input Voltage for Main Unit
+6
V
Max. Input Current for Main Unit
50
mA
Max. Input Voltage for Thermoelectric Cooler
2.6
V
Max. Input Current for Thermoelectric Cooler
2.2
A
Effective Area
5
mm
Peak Sensitivity Wavelength
580
800
nm
420 nm
4.7 × 10⁵
6.5 × 10⁴
Count Sensitivity Typ. 550 nm
7.6 × 10⁵
2.1 × 10⁵
s^-1·pW^-1
800 nm
—
3.9 × 10⁵
Count Linearity *¹
1.5 × 10⁶
1.5 × 10⁶
s^-1
Typ.
100
Dark Count *² *³
Max.
300
125
s^-1
375
Pulse-pair Resolution
70
ns
Output Pulse Width
30
ns
Min.
Output Pulse Height *⁴
Typ.
3.0
V
3.6
Recommended Load Resistance
50
Ω
Signal Output Logic
Positive logic
—
Operating Ambient Temperature *⁵
+5 to +35
°C
Storage Temperature *⁵
-20 to +50
°C
Weight
340
g
*1: Random pulse, at 10 % count loss *2: PMT setting temperature 0 °C, used with C8137, M9011 and A7432
*3: After 30 minutes storage in darkness *4: With input voltage +5 V, Load resistance 50 Ω and Coaxial cable RG-174/U (450 mm)
*5: No condensation
Cooling Specifications
Parameter
Cooling Method
Max. Cooling Temperature (∆T) *⁶
Cooling Time *⁶
*6: Input current to thermoelectric cooler = 2 A
52
H7421-40 / H7421-50
Thermoelectric cooling
35
Approx. 5
Unit
—
°C
min