Up and down conversion systems for production of emitted light from various energy sources

A system for energy upconversion inside a medium to induce a biological change in the medium, comprising:

• an up-converter particle disposed in the medium and configured, upon exposure to a first wavelength λ1 of radiation, to generate a second wavelength λ2 of radiation having a higher energy than the first wavelength λ1;
• a photoactivatable drug in a vicinity of the up-converter particle,
• wherein
• the second wavelength λ2 of radiation comprises ultraviolet light generated within the medium surrounding the up-converter particle, and
• said ultraviolet light from the up-converter particle produces said biological change to an entity in the medium by activation of the photoactivatable drug with said ultraviolet light generated within the medium.

A system for energy upconversion inside a medium, comprising:

• an up-converter particle disposed in the medium and configured, upon exposure to a first wavelength λ1 of radiation, to generate a second wavelength λ2 of radiation having a higher energy than the first wavelength λ1;
• and
• a metallic structure disposed in relation to the particle and inside the medium,
• wherein
• the second wavelength λ2 of radiation comprises ultraviolet emission generated within the medium surrounding the particle and the metallic structure, and
• said ultraviolet emission produces a biological change to an entity in the medium, wherein the second wavelength λ2 sterilizes a pathogen inside the medium.

A readable article comprising:

• a medium containing identification information;
• an upconverter particle included in or on the surface of the medium;
• and
• said up-converter particle configured, upon exposure to a first wavelength λ1 of radiation, to emit a second wavelength λ2 of radiation having a higher energy than the first wavelength λ1,
• wherein said second wavelength λ2 is visible light, and
• said visible light has an intensity permitting human observation of the identification information.

A system for energy upconversion inside a medium, comprising:

• an up-converter particle disposed in the medium and configured, upon exposure to a first wavelength λ1 of radiation, to generate a second wavelength λ2 of radiation having a higher energy than the first wavelength λ1;
• and
• wherein
• the second wavelength λ2 of radiation comprises ultraviolet emission generated within the medium surrounding the up-converter particle, and
• said ultraviolet emission produces a change in biological activity of an entity in the medium.