Holographic color display device having a color filter with parallel, vertical color stripes of primary colors
View Patent ↗A color filter with parallel, vertical color strips of the RGB base colors associated with the image separating element, the color strips repeating horizontally within the color filter in periodic fashion. The light modulator contains a sequence of two registered holograms for each base color interlaced into six pixel columns for a left observer eye and for a right observer eye, and the sequence is repeated horizontally in periodic fashion. The periods of the color filter and the hologram are arranged relative to one another with the same degree of expansion, with a color strip and at least two pixel columns with holograms of the base color of the color strip are associated with a separating element.
1. Holographic colour display device comprising, in an optical path: light source means, focussing optical means, a controllable light modulator, and an optical image separation means with vertical separating elements, where the focussing optical means image sufficiently coherent light through controllable pixels of the controllable light modulator into an observer plane, said controllable pixels are arranged in the form of a matrix, and where the light is superposed to form visibility regions for observer eyes, and where the vertical separating elements of the optical image separation means image pixel columns in which holograms are encoded into respective visibility regions for each observer eye, wherein
The image separation means is assigned with an external colour filter whose material comprises parallel vertical colour stripes of primary colours which are periodically repeated in a horizontal direction in the colour filter,
The light modulator comprises a sequence of two inscribed holograms for each primary colour which are interleaved for a left and a right observer eye in six pixel columns, where the sequence of the holograms is periodically repeated in a horizontal direction in the light modulator, and
periods of the colour filters and of the holograms have an identical size and are arranged in relation to each other such that each separating element is assigned with one colour stripe of the colour filter and at least two pixel columns with holograms of the primary colour of that colour stripe, in order to generate multi-coloured visibility regions.
2. Holographic display device according to claim 1 , wherein the pixel columns which are assigned to a colour stripe of the primary colour comprise a hologram which has been computed for that primary colour.
3. Holographic display device according to claim 2 , wherein one visibility region contains the superposed coloured images of all pixel columns for the left observer eye, and the other visibility region contains the superposed coloured images of all pixel columns for the right observer eye, thus holographically generating a multi-coloured three-dimensional object for the observer eyes.
4. Holographic display device according to claim 1 , wherein a horizontal tracking of the multi-coloured visibility regions is effected by horizontally displacing the encoding of the holograms on the light modulator.
5. Holographic display device according to claim 1 , wherein the pixel columns are imaged by the separating elements of the image separation means in a defocussed manner into the observer plane.
6. Holographic display device according to claim 1 , wherein each separating element is additionally assigned with further, non-activated pixel columns in order to increase the stereo contrast.
7. Holographic display device according to claim 1 , wherein a side of the image separation means which is structured with the separating elements is attached to the colour filter and the image separation means and the colour filter form one unit.