White-light flashlight activated up-conversion luminescence for ultraviolet-B tagging.

Area of Science:

• Materials Science
• Optics
• Photonics

Background:

• Optical tagging is valuable for object identification, especially in bright environments.
• Existing technologies lack efficient solutions for covert marking in such conditions.
• Up-converting phosphors offer potential for specialized optical tagging applications.

Purpose of the Study:

• To develop a covert optical tagging technology emitting in the ultraviolet-B (UV-B) region.
• To demonstrate the feasibility of using a standard white-light flashlight as an excitation source for UV-B up-conversion.
• To establish a practical method for object marking and differentiation using UV-B emission.

Main Methods:

• Utilized up-converting phosphors, specifically Lu3Al5O12:Pr3+, for UV-B emission.
• Employed a white-light flashlight as the excitation source for the up-conversion process.
• Applied an ultraviolet camera for detecting the emitted UV-B light.

Main Results:

• Successfully demonstrated UV-B emission from phosphors upon excitation with a white-light flashlight.
• Confirmed the feasibility of using a convenient flashlight as an excitation source for up-conversion, a novel approach.
• Showcased the potential for marking and differentiating objects using this flashlight-pumped UV-B tagging technology.

Conclusions:

• The developed flashlight-pumped UV-B tagging technology offers a promising solution for covert object identification in visually bright environments.
• This method is versatile and applicable to various phosphors, broadening its potential use.
• The technology has broad applicability in commercial, civilian, and military sectors for object marking and authentication.