Giesecke & Devrient Gmbh

Other

Bundesdruckerei Gmbh

Guenther Dausmann

Klaus Gnaedig

Thorstein Halldorsson

A method for producing an optical element, preferably a security feature, wherein a film having a first embossed hologram in an embossing layer is provided, and a second embossed hologram is embossed into the same embossing layer such that the first embossed hologram is partly replaced with the second embossed hologram. The invention further relates to a method for producing an optical element wherein an embossable film provided with an embossed hologram is partly filled with printing lacquer, and a method for producing an optical element wherein hologram embossing is prevented by prior partial printing of the embossing film with curable printing lacquer. The invention relates further to optical features producible by the inventive methods, documents of value having an inventive optical feature and a numbering embosser for use in an inventive production method.

Optical element and method for the production thereof

The invention relates to an optical feature, in particular for documents of value, having at least one at least dual-channel hologram for the holographic reconstruction of different images from different directions of gaze, wherein different regions of the hologram are associated with the different channels and the regions of the hologram reconstructing the respective image under incident light have sub-regions which do not take part in the image reconstruction, to a data carrier having at least one optical feature of the invention and to a method for the manufacture of an optical feature, in particular for documents of value.

Optical feature, in particular for documents of value, and a manufacturing method for the later individualization or data storage

In a holographic screen for laser front projection, of at least one or more laser wavelengths that selectively back-scatter the incident spectrally narrow-band laser radiation in a predetermined solid angle and simultaneously highly absorbs the disturbing spectrally broad-band ambient light, it is proposed that it have at least one holographic volume grating that is optically coupled to a light absorber.

Screen for front laser projection

The invention concerns a holographic screen for the laser back-projection of at least one or a plurality of laser wavelengths, said holographic screen selectively and diffusely front-scattering the incident narrow-band laser radiation in a predetermined solid angle and simultaneously allowing through the disruptive spectrally broad-band ambient light from the observation area. To that end, the holographic screen comprises at least one holographic transmission grid which is coupled to a light absorber.

Screen for laser rear projection

A method for the production of holograms proof against copying and imitation possessing authenticity features, which are copies of a master hologram. In accordance with the invention as a master hologram a hologram of a randomly structured optical element, as for example a diffusion plate, which constitutes the authenticity feature, is recorded and each hologram copy produced from the master hologram is provided with a layer having at least one layer with a color succession and/or the hologram copy produced on a thick light sensitive layer is caused to shrink or to expand.

Growing community of inventors

Erding, Germany

Guenther Dausmann