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There is no radiation survey meter that can discriminate among alpha particles, beta particles, and gamma-rays with one material. Previously, undoped poly(ethylene terephthalate) (PET) has been shown to be an effective material for beta particle and gamma-ray detection. Here, we demonstrate a prototype survey meter for alpha particles based on undoped PET. A 140 × 72 × 1-mm PET substrate was fabricated with mirrored surfaces. It was incorporated in a unique detection section of the survey meter that directly detects alpha particles. The prototype exhibited an unambiguous response to alpha particles from a 241 Am radioactive source. These results demonstrate that undoped PET can perform well in survey meters for alpha particle detection. Overall, the PET-based survey meter has the potential to detect multiple types of radiation, and will spawn an unprecedented type of radiation survey meter based on undoped aromatic ring polymers.

Applications of poly (ethylene naphthalate) (PEN) in radiation safety are attractive. However, for worker safety at nuclear power reactors, further enhancements of undoped scintillation materials are required for alpha particle detection. Here, we show that restrictions on the maximum light extraction from PEN can be lifted by controlling its surface conditions. Specifically, 1 mm-thick PEN plates with various degrees of surface asperities were examined. Emission and transmission spectra indicated little effect on the emission wavelengths of the generated light, but large effect on the propagation directions. These features resulted in excellent instrument efficiency for short-range alpha particles in radioactive contamination inspection devices that incorporated PEN having several tens of μm deep surface scratches. We modelled the relationship between surface asperities and instrument efficiencies for alpha particles by imaging the surface conditions with scanning electron microscopy. Surface asperities led to a quasi-decrease in the critical angle of the light generated around the surface boundary plane, which then resulted in an increase in total internal reflections at the plane. This knowledge should initiate general interest in PEN for radiological management devices.