Illuminating device
AssigneeNanogate Advanced Materials GmbH
InventorMartin Stadtwald-Klenke
Life of this patent
Estimating the term…
Abstract
An illuminating device for backlighting flat displays, in particular displays for mobile applications, is provided. The illuminating device includes a light source and a light guiding member into which light emitted from the light source is coupled in and is coupled out therefrom at an exit surface. The exit surface has a surface structure including diffractive surface elements for light propagation, wherein all surface elements have a surface structure with a constant amplitude.
Claims25
An illuminating device for backlighting flat displays, comprising:
- a light source;
- and
- a light guiding member into which light emitted from the light source is coupled in and is coupled out therefrom at an exit surface, the exit surface having a surface structure including an array of individually spaced diffractive surface elements for light propagation, wherein the diffractive surface elements act as diffraction gratings and wherein individual surface elements comprise different diffraction gratings, and wherein the diffractive surface elements have a size at the exit surface of between 0.04 μm2 and 10,000 μm2, and wherein each diffractive surface element is cube shaped with a top surface being a light emitting surface having two sinusoidal half-waves.
A flat display comprising:
- a liquid crystal element;
- and
- an illuminating device backlighting the liquid crystal element, the illuminating device having a light source and a light guiding member having an exit surface, the exit surface having a surface structure including an array of individually spaced diffractive surface elements for light propagation, wherein the diffractive surface elements act as diffraction gratings and wherein individual surface elements comprise different diffraction gratings, and wherein the diffractive surface elements have a size at the exit surface of between 0.04 μm2 and 10,000 μm2 and wherein each diffractive surface element is cube shaped with a top surface being a light emitting surface having two sinusoidal half-waves.
An illuminating device for backlighting flat displays, comprising:
- a light guiding member having a side face, a bottom face, a plurality of side faces, and an exit surface comprising an array of individually spaced diffractive surface elements;
- a light source arranged along the side face of the light guiding member;
- a parabolic reflector surrounding the light source with an open side of the parabolic reflector being directed towards the side face so as to couple light emitted from the light source into the light guiding member;
- and
- a reflecting device provided at the bottom face and the plurality of side faces, wherein each diffractive surface element is cube shaped with a top surface being a light emitting surface having two sinusoidal half-waves.
Dependencies are inferred from the claim text.