Tuesday, May 08, 2007

US Patent 7213923 - Fluorescent nanoparticles in transparent substrate

http://www.freepatentsonline.com/7213923.html

Fluorescence is generally defined as the emission of electromagnetic radiation, generally visible light, stimulated in a substance by the absorption of incident radiation and persisting only as long as the stimulating radiation is continued. The use of quantum dots to achieve fluorescence has been known for decades and may have existed since medieval times when artisans made stained glass windows. Nevertheless this patent presents a broad claim to transparent substrates with fluorescent nanoparticles (which may include atoms, molecules, or any other particles less than 500 nm in diameter). Claims 1, 37, and 38 reads:

1. An apparatus comprising light emitting material integrated into a substantially transparent substrate, wherein: the light emitting material is configured to emit visible light in response to absorption of excitation light; the wavelength of the visible light varies according to the wavelength of the excitation light; the light emitting material comprises a plurality of light emitting particles; and each of the plurality of light emitting particles has a diameter less than about 500 nanometers.

37. The apparatus of claim 1, wherein each of the plurality of light emitting particles is an individual molecule.

38. The apparatus of claim 1, wherein each of the plurality of light emitting particles is an individual atom.

While these claims would seem to place the holder of this patent (a company called Superimaging) as the owner of all fluorescent materials (especially in light of claims 37 and 38 since everything is fundamentally made of atoms or molecules and the physics of fluorescence happens on the molecular or atomic level) there is plenty of prior art missed (or not understood) by the Examiner to invalidate this patent. See for example US 7,094,361
http://www.freepatentsonline.com/7094361.html.

Labels: