Abstract: There is described a security element or document comprising a substrate (20) and at least a first dynamic-effect feature (100; 120; 121; 122; 123; 130; 135; 140; 150; 171; 181; 191; 200) provided on the substrate which includes a dynamic-effect component that is responsive to illumination stimulus of a selected excitation wavelength or wavelength band to produce an optical spectral response, which optical spectral response changes dynamically over an observable period of time between multiple color appearances (C, F, M; C1, M1) upon and while being subjected to the illumination stimulus.

Abstract: There is described a security element or document comprising a substrate (20) and at least a first dynamic-effect feature (100; 120; 121; 122; 123; 130; 135; 140; 150; 171; 181; 191; 200) provided on the substrate which includes a dynamic-effect component that is responsive to illumination stimulus of a selected excitation wavelength or wavelength band to produce an optical spectral response, which optical spectral response changes dynamically over an observable period of time between multiple color appearances (C, F, M; C1, M1) upon and while being subjected to the illumination stimulus.

Abstract: Three-dimensional objects are displayed in real time within a solid volume of optically transparent material by utilizing two infrared laser beams of different wavelengths to create visible light inside the display material via a two-photon upconversion process. Objects comprising points, lines, surfaces, and volumes are drawn by decomposing them into a set of small three-dimensional cells or "voxels" located at specific coordinates inside the display medium. Individual voxels are addressed and activated by intersecting the two invisible infrared laser beams at the appropriate coordinate locations. The display material is tailored to provide efficient upconversion in the region of intersection, with minimal visible light generated outside this region by either one of the infrared beams alone. Typical media are rare-earth-doped glasses or crystals having low phonon energies.

Abstract: Three-dimensional objects are displayed in real time within a solid volume of optically transparent material by utilizing two infrared laser beams of different wavelengths to create visible light inside the display material via a two-photon upconversion process. Objects comprising points, lines, surfaces, and volumes are drawn by decomposing them into a set of small three-dimensional cells or "voxels" located at specific coordinates inside the display medium. Individual voxels are addressed and activated by intersecting the two invisible infrared laser beams at the appropriate coordinate locations. The display material is tailored to provide efficient upconversion in the region of intersection, with minimal visible light generated outside this region by either one of the infrared beams alone. Typical media are rare-earth-doped glasses or crystals having low phonon energies.

Abstract: Three-dimensional objects are displayed in real time within a solid volume of optically transparent material by utilizing two infrared laser beams of different wavelengths to create visible light inside the display material via a two-photon upconversion process. Objects comprising points, lines, surfaces, and volumes are drawn by decomposing them into a set of small three-dimensional cells or "voxels" located at specific coordinates inside the display medium. Individual voxels are addressed and activated by intersecting the two invisible infrared laser beams at the appropriate coordinate locations. The display material is tailored to provide efficient upconversion in the region of intersection, with minimal visible light generated outside this region by either one of the infrared beams alone. Typical media are rare-earth-doped glasses or crystals having low phonon energies.

Abstract: Three-dimensional objects are displayed in real time within a solid volume of optically transparent material by utilizing two infrared laser beams of different wavelengths to create visible light inside the display material via a two-photon upconversion process. Objects comprising points, lines, surfaces, and volumes are drawn by decomposing them into a set of small three-dimensional cells or "voxels" located at specific coordinates inside the display medium. Individual voxels are addressed and activated by intersecting the two invisible infrared laser beams at the appropriate coordinate locations. The display material is tailored to provide efficient upconversion in the region of intersection, with minimal visible light generated outside this region by either one of the infrared beams alone. Typical media are rare-earth-doped glasses or crystals having low phonon energies.