Optical display device
An optical display device arranged to create a perception of a sky scene in output light, the optical display device comprising: a collimated light generation system comprising a light source and a collimating system; a diffuse light generation system, and; an output aperture for the output light; the diffuse light generation system arranged to generate a diffuse skylight component in the output light, and the collimated light generation system arranged to generate a collimated sunlight component in the output light, wherein the light source comprises a planar array of light sources arranged on a common substrate, the collimating system comprises a planar array of collimating members that comprise lenses formed integrally from a common substrate, the light sources each arranged with an associated collimating member so that light emitted from the light sources is collimated, and the planar array of light sources and the planar array of collimating members are aligned with a plane of the output aperture.
1 . An optical display device arranged to create a perception of a sky scene in output light, the optical display device comprising:
a collimated light generation system comprising a light source and a collimating system;
a diffuse light generation system, and;
an output aperture for the output light;
the diffuse light generation system arranged to generate a diffuse skylight component in the output light, and the collimated light generation system arranged to generate a collimated sunlight component in the output light,
wherein the light source comprises a planar array of light sources arranged on a first common substrate,
the collimating system comprises a planar array of collimating members that comprise lenses formed integrally from a second common substrate,
the light sources each arranged with an associated collimating member so that light emitted from the light sources is collimated, and
the planar array of light sources and the planar array of collimating members are aligned with a plane of the output aperture,
wherein the device is configured with the output aperture arranged for viewing whilst mounted to a wall or ceiling from a viewing distance of greater than 0.5 m, and the output aperture has a side length of at least or greater than 0.5m,
the device comprising an alignment system arranged to align the first common substrate and the second common substrate such that the light sources are each arranged in alignment with an associated collimating member.
2 . The optical display device of claim 1 , wherein the lenses of the planar array are formed of a plastic based material by compression moulding and have a square or hexagonal shape.
3 . The optical display device of claim 1 , wherein the collimating system comprises a second planar array of collimating members that comprise lenses formed integrally from a third common substrate, wherein an optical axis of the lenses of the planar array is aligned with an optical axis of the lenses of the second planar array.
4 . The optical display device of claim 1 , wherein light guides couple the light sources to the lenses of the collimating system, wherein the light guides are formed integrally from a fourth common substrate.
5 . The optical display device of claim 1 , wherein the light sources are printed on the first common substrate, and the first common substrate of the light sources is arranged as a printed circuit board.
6 . The optical display device of claim 1 , wherein the light sources are LEDs, that have a chip size of one of the following:
less than 100 μm or;
100-200 μm, and;
0.1 mm-3 mm.
7 . The optical display device of claim 1 , wherein a diameter of the lenses is one of the following:
less than 1 mm or;
1-2 mm;
1 mm-30 mm.
8 . The optical display device of claim 1 , wherein the collimated light generation system includes an optical element arranged to diffusively reflect stray light from the collimating system, the optical element is arranged as a plurality of cells, with an open entrance end to receive light from the collimating system and an open exit end to output light, wherein a pitch of the cells is less than a diameter of the lenses and/or the cells are arranged so that a central axis of at least some of the cells is not aligned with the optical axis of the lenses and/or a depth of the cells is 2-120 times a pitch of the cells.
9 . The optical display device of claim 1 , comprising a thermal compensation arrangement, which is configured to maintain an optical axis of the lenses in alignment with a central axis of the associated light source at an operating temperature range of said device.
10 . The optical display device of claim 9 , wherein the operating temperature range is 10-30 degrees Celsius.
11 . The optical display device of claim 9 , wherein the optical axis of the lenses is maintained in alignment with the central axis of the light source, such that a periphery of a light cone of a light source is maintained within a periphery of an associated lens.
12 . The optical display device of claim 9 , wherein the thermal compensation arrangement comprises a thermal expansion coefficient α1 of the first common substrate of the light sources and a thermal expansion coefficient α2 of the second common substrate of the lenses, wherein:
1) α1 and α2 are selected such that the optical axis of the lenses is maintained in alignment with the central axis of the light source at the operating temperature, and is not maintained in alignment outside of said operating temperature, or;
2) α1 and α2 are matched such that the optical axis of the lenses is maintained in alignment with the central axis of the light source at the operating temperature, and is maintained in alignment outside of said operating temperature.
13 . The optical display device of claim 1 , wherein the diffuse light generation system comprises a diffuser, with a diffuse light source coupled to an edge of the diffuser, wherein the diffuser is arranged with the collimated sunlight component to project therethrough.
14 . The optical display device of claim 1 wherein a depth of the optical display device is less than 5 or 2 or 1 cm.
15 . A method of assembling a device to create a perception of a sky scene in output light, the method comprising arranging the following items on parallel planes to each other:
a planar array of light sources arranged on a first common substrate;
a planar array of collimating members that comprise lenses arranged integrally on a second common substrate, and;
an output aperture;
wherein the device is configured with the output aperture arranged for viewing whilst mounted to a wall or ceiling from a viewing distance of greater than 0.5 m, and the output aperture has a side length of at least or greater than 0.5m,
the device comprising an alignment system arranged to align the first common substrate and the second common substrate such that the light sources are each arranged in alignment with an associated collimating member.
16 . A method of generating a perception of a sky scene in output light, the method comprising:
generating a collimated sunlight component in the output light with a planar array of light sources arranged on a first common substrate, which project through a collimating system that is arranged as a planar array of collimating members that comprise lenses arranged integrally on a second common substrate, and;
generating a diffuse skylight component in the output light with a diffuse light generation system;
wherein the device is configured with the output aperture arranged for viewing whilst mounted to a wall or ceiling from a viewing distance of greater than 0.5 m, and the output aperture has a side length of at least or greater than 0.5m,
the device comprising an alignment system arranged to align the first common substrate and the second common substrate such that the light sources are each arranged in alignment with an associated collimating member.
17 . The optical display device of claim 1 wherein the alignment system may include one or more of the following configurations: protrusions that extend through apertures in one or both the substrates; aligned peripheral edges that are held in alignment with each other by a clamp, which may be formed as part of a housing of the display device.
18 . An optical display device arranged to create a perception of a sky scene in output light, the optical display device comprising:
a collimated light generation system comprising a light source and a collimating system;
a diffuse light generation system, and;
an output aperture for the output light;
the diffuse light generation system arranged to generate a diffuse skylight component in the output light, and the collimated light generation system arranged to generate a collimated sunlight component in the output light,
wherein the light source comprises a planar array of emission sources,
the collimating system comprises a planar array of collimating members that comprise lenses formed integrally from a common substrate,
the emission sources each arranged with an associated collimating member so that light emitted from the emission sources is collimated, and
the planar array of emission sources and the planar array of collimating members are aligned with a plane of the output aperture,
wherein the device is configured with the output aperture arranged for viewing whilst mounted to a wall or ceiling from a viewing distance of greater than 0.5 m, and
the output aperture has a side length or diameter of at least or greater than 0.5m,
the device comprising an alignment system arranged to align the planar array of emission sources and the common substrate such that the emission sources are each arranged in alignment with an associated collimating member.
19 . The optical display device of claim 17 comprising an air gap arranged between the planar array of emission sources and the planar array of collimating members.
20 . The optical display device of claim 17 , wherein light of the collimated light generation system is projected via a light guide to the planar array of collimating members.
21 . The optical display device of claim 19 , wherein the light guide receives light from an emitting portion of the light source and conveys the light to an output surface of the light guide.
22 . The optical display device of claim 1 , comprising an air gap arranged between the planar array of light sources and the planar array of collimating members.