OPTICAL WAVEGUIDE FOR A DISPLAY DEVICE
The disclosure relates to an optical waveguide for a display device and to a method for producing such an optical waveguide. The optical waveguide has a substrate on which a hologram layer is arranged. A cover layer includes a light-transmissive material that has been subjected to a curing process is arranged on the hologram layer. The substrate can consist of glass. Alternatively, the substrate likewise consists of a light-transmissive material that has been subjected to a curing process.
1 . An optical waveguide for a display device, the optical waveguide comprising:
a substrate;
a hologram layer arranged on the substrate; and
a cover layer arranged on the hologram layer;
wherein the cover layer includes a light-transmissive material that has been subjected to a curing process.
2 . The optical waveguide as claimed in claim 1 , wherein the substrate includes glass or also of a light-transmissive material that has been subjected to a curing process.
3 . The optical waveguide as claimed in claim 1 , wherein the light-transmissive material is a lacquer or an optically clear adhesive.
4 . The optical waveguide as claimed in claim 3 , wherein the light-transmissive material that has been subjected to a curing process has a refractive index of greater than or equal to 1.4.
5 . The optical waveguide as claimed in claim 1 , wherein the substrate or the cover layer has a structuring.
6 . A method for producing an optical waveguide, the method comprising the steps of:
applying a layer of a light-transmissive material onto a first mold plate;
curing the applied light-transmissive material to form a cover layer;
applying a hologram layer onto the cover layer;
applying a substrate onto the hologram layer; and
exposing the hologram layer to light and curing the hologram layer.
7 . The method as claimed in claim 6 , wherein a separating layer is arranged between the first mold plate and the layer of the light-transmissive material or between a second mold plate and the layer of the light-transmissive material.
8 . The method as claimed in one of claims 6 , wherein the first mold plate or a second mold plate has a structuring.
9 . A method for producing an optical waveguide, the method comprising the steps of:
applying a layer of a light-transmissive material onto a first mold plate;
curing the applied light-transmissive material to form a cover layer;
applying a hologram layer onto the cover layer;
exposing the hologram layer to light and curing the hologram layer;
applying a layer of a light-transmissive material onto the hologram layer;
shaping the applied light-transmissive material by a second mold plate; and
curing the applied light-transmissive material to form a substrate.
10 . The method as claimed in claim 9 , wherein a separating layer is arranged between the first mold plate and the layer of the light-transmissive material or between the second mold plate and the layer of the light-transmissive material.
11 . The method as claimed in one of claim 7 , wherein the first mold plate or the second mold plate has a structuring.
12 . A device for generating a virtual image, the device comprising:
an image-generating unit for producing an image; and
an optics unit for projecting the image in the direction of a mirror unit for generating the virtual image;
wherein the device has at least one optical waveguide as claimed in claim 1 for expanding an exit pupil.