Pyrodetector Comparison

Sensor specifications

MPY-01 MPY-RS MPY-RS2 SPY
Responsivity (kV/W)* 7.5 13 70 7.5
Noise (µV/√Hz) 13 18 25 13
NEP (pW/√Hz)* 1500 1400 400 1500
Detectivity (cm√Hz/W)* @ 10 Hz 1.8⋅108 2.0⋅108
5.0⋅108 1.8⋅108
Detectivity (cm√Hz/W)* @ 1 kHz 0.4⋅108 1.1⋅108 2.0⋅108 0.4⋅108
Detection bandwidth
(depends on window)
UV - THz UV - THz UV - THz UV - THz
Frequency range 1Hz - 500 Hz 1 Hz - 5 kHz 1 Hz - 100 kHz
1Hz - 200 Hz
Power supply MN21 battery
(>30h operating time)
Low noise power supply
(±12V, Thorlabs LDS12B)
Low noise power supply
(±12V, Thorlabs LDS12B)
Low noise power supply
(±12V, Thorlabs LDS12B)
Dimensions (mm) h: 63.0
w: 48.5
d: 20.4
h: 64.0
w: 48.5
d: 21.0
h: 59.8
w: 45.3
d: 21.0
h: 24.25
w: 28.0
d: 12.9

* Measured with broadband black body source at 150°C, central wavelength λ = 6.8 µm and KBr window

Available detector windows

Material Transmission region
Wavelength Frequency Wavenumber
KBr 200 nm - 30 µm (10 - 1,500) THz (333 - 50,000) cm-1
CsI 400 nm - 40 µm (7.5 - 750) THz (250 - 25,000) cm-1
Si > 1.2 µm < 250 THz < 8,333 cm-1
PTFE (20 - 40) µm and  > 60 µm (7.5 - 15) THz and < 5 THz (250 - 500) cm-1 and < 167 cm-1
HDPE > 40 µm < 7.5 THz < 250 cm-1
Diamond > 225 nm
< 1,332 THz
< 44,444 cm-1

Not sure which detector is best for you?
Please ask yourself these 6 questions:

  1. What repetition rate is your light source? 
    Pyroelectric detectors can only observe a change of radiation intensity - continuous wave (CW) sources will not give a signal. If you want to measure a CW source, you have to chop the beam at a frequency suitable for your detector. The MPY-RS detector can be used for repetition rates / chopping frequencies of many kHz.
  2. What is your expected incident power range?
    All detectors are highly sensitive. If you want to measure higher power you probably need to attenuate your beam (see our tutorial).
  3. Do you need an external power supply for long-term measurements?
    Both MPY-RS and SPY detectors are powered by an external power supply.

  4. Do you need vacuum compatibility?
    Take a look at our SPY vacuum compatible version.

  5. Do you have size limitations in your setup?
    Compare the detector dimensions (see table 1 above). The SPY detector has the smallest footprint.

  6. Which incident wavelength range do you want to cover?
    Our pyroelectric detectors are sensitive from the UV to the terahertz / far infrared. The usable wavelength range only depends on the detector window. We offer various windows for all detectors (see table 2 above).