Photomultiplier Tubes (PMTs)

PMT Introduction:

Photomultipliers Tubes (photomultipiers or PMTs for short) are traditional vacuum tubes designed to receive photon's from Scintillators and convert those photo's to electron's. These detectors multiply the current produced by incident light by as much as 100 million times (i.e., 160 dB), in multiple dynode stages, enabling (for example) individual photons to be detected when the incident flux of light is very low.

The combination of high gain, low noise, high frequency response or, equivalently, ultra-fast response, and large area of collection has maintained photomultipliers an essential place in nuclear and particle physics, astronomy, medical diagnostics including blood tests, medical imaging, motion picture film scanning (telecine), radar jamming, and high-end image scanners known as drum scanners.

PMT Advantage:

PMT's have been around for a long time, and were reportedly first used by RCA in 1934 to capture photon's and covert them to electronic impulses.  The RCA division located in Lancaster, Pennsylvania was later purchased by Burle Industries which had worked directly with FlashPoint to provide PMT's to the downhole tool and MWD sector. 

500 PMTsa

However, after Burle Industries was purchased by Photonis USA and effectively closed in 2009, FlashPoint has worked directly with additional high quality


PMT manufacturers.

PMT's have the advantage in working in a wide range of temperatures provided that the required voltage is available and provided that the vacuum tube is not damaged by excessive vibration or shock.

The downside has been size, need for magnetic shielding, and paring to the scintillator to ensure compatibility with refraction index and optical window size.

PMT Detector Specifications:

CasingGlass Vacuum TubeSilicon Wafer
ShapeCylindricalSquare or Cylindrical
WindowBorosilicate N/A
HeadNot Threaded or ThreadedNot Threaded or Threaded
Temperature-35C to 175C
(-31F to 347F)
-35C to 20C
(-31F to 68F)
Vibration100g 11 milisecondN/A
Spectral Response Range300-650300-800
Max Emission (nm)400420
Refractive Index1.51N/A
PMT Common sizes and part-numbers:

TypeMax. TemperatureShapeOutside Casing SizeModel No.
PMT125Cylindrical1.08" (27.5 mm) x 3.34" (85.0 mm)FPPML-108-334
PMT150Cylindrical1.08" (27.5 mm) x 3.34" (85.0 mm)FPPMM-108-334
PMT175Cylindrical1.08" (27.5 mm) x 3.34" (85.0 mm)FPPMH-108-334
PMT125Cylindrical1.1" (28 mm) x 4.13" (105.0 mm)FPPML-110-413
PMT150Cylindrical1.1" (28 mm) x 4.13" (105.0 mmFPPMM-110-413
PMT175Cylindrical1.1" (28 mm) x 4.13" (105.0 mmFPPMH-110-413
SiPM Contact UsCylindrical or SquareTBDTBD
Size Selection:

To ensure that your scintillator output window matches your detector input window please confirm with our technical staff to confirm comparability. To learn more and to place an order please contact us.

Additional Options:

Additional Options Include:



FlashPoint takes great care in shipping your order to you.  Each PMT detector is individually packaged inside tough industrial strength tubes that you can later re-use to ship or store other valuable components.

Delivery Terms:

Please contact us to confirm current inventory and to confirm delivery date based on size of order and location of delivery.  We do accept transportation on your shipping account.


FlashPoint provides a 1 year "no-nonsense" limited warranty on its PMT Products

  • Scintillators


    A scintillator is used to produce measurable light (photons) that emit after the scintillator has absorbed radiation energy and begins…

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  • Optical Pads

    Optical Pads

    Optical Pads protect the optical windows of the Scintillator and Detector from normal wear & tear and irreversible damage.

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  • Detectors


    A detector is used to count the photons produced by a Scintillator by converting photons to electrons and multiplies (amplifies)…

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  • Heat Tags

    Heat Tags

    An irreversible Heat Tag is used to confirm maximum temperatures are kept within warranty range.

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  • Magnetic Shield

    Magnetic Shield

    Magnetic shielding protect the Detector from background radiation (noise) which may lead to falsely high detector counts.

    Read more

  • Voltage Divider

    Voltage Divider

    A Voltage Divider is used with high voltage detectors where leakage currents sometimes result in unwanted "dark current" pulses that…

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