Plastic scintillating fiber and its manufacturing method

A method for manufacturing a plastic scintillating fiber, the fiber comprising:

• an outer peripheral layer containing a resin having scintillating properties, the resin containing:
• a compound of a heavy metal element;
• and
• at least one type of a first fluorescent substance that absorbs a first scintillation light emitted from the resin and wavelength-converts the first absorbed light into a first light having a wavelength longer than that of the first scintillation light;
• a core disposed inside the outer peripheral layer and containing at least one type of a second fluorescent substance that absorbs the first light emitted from the first fluorescent substance and wavelength-converts this second absorbed light into a second light having a wavelength longer than that of the second absorbed light;
• and
• a cladding layer covering an outer peripheral surface of the core and having a refractive index lower than that of the core, and
• the method comprising:
• a process of manufacturing a preform by inserting a second cylindrical body for the cladding layer into a first cylindrical body for the outer peripheral layer, and inserting a rod for the core into the second cylindrical body;
• and
• a process of drawing the preform while heating the preform, wherein
• the first scintillation light is ultraviolet light having a wavelength of 250 to 350 nm, and
• the second light emitted from the second fluorescent substance has a wavelength of 350 to 600 nm.

A method for manufacturing a plastic scintillating fiber, the fiber comprising:

• an outer peripheral layer containing a resin having scintillating properties, the resin containing:
• a compound of a heavy metal element;
• and
• at least one type of a first fluorescent substance that absorbs a first scintillation light emitted from the resin and wavelength-converts the first absorbed light into a first light having a wavelength longer than that of the first scintillation light;
• a core disposed inside the outer peripheral layer and containing at least one type of a second fluorescent substance that absorbs the first light emitted from the first fluorescent substance and wavelength-converts this second absorbed light into a second light having a wavelength longer than that of the second absorbed light;
• and
• a cladding layer covering an outer peripheral surface of the core and having a refractive index lower than that of the core, and
• the method comprising:
• coating the outer peripheral layer on a surface of a wavelength shifting fiber containing the core and the cladding layer, wherein
• the first scintillation light is ultraviolet light having a wavelength of 250 to 350 nm, and the second light emitted from the second fluorescent substance has a wavelength of 350 to 600 nm.