Anamorphic directional illumination device

An anamorphic near-eye display apparatus comprising:

• an illumination system comprising a spatial light modulator, the illumination system being arranged to output light;
• and
• an optical system arranged to direct light from the illumination system to a viewer's eye, wherein the optical system has an optical axis and has anamorphic properties in a lateral direction and a transverse direction that are perpendicular to each other and perpendicular to the optical axis, wherein the spatial light modulator comprises pixels distributed in the lateral direction, and the optical system comprises:
• a transverse anamorphic component having positive optical power in the transverse direction, wherein the transverse anamorphic component is arranged to receive light from the spatial light modulator and the illumination system is arranged so that light output from the transverse anamorphic component is directed in directions that are distributed in the transverse direction;
• an extraction waveguide arranged to receive light from the transverse anamorphic component;
• a lateral anamorphic component having positive optical power in the lateral direction, the extraction waveguide being arranged to guide light from the transverse anamorphic component to the lateral anamorphic component along the extraction waveguide in a first direction;
• and
• a light reversing reflector that is arranged to reflect light that has been guided along the extraction waveguide in the first direction so that the reflected light is guided along the extraction waveguide in a second direction opposite to the first direction,
• wherein
• the extraction waveguide comprises an array of extraction features, the extraction features being arranged to transmit light guided along the extraction waveguide in the first direction and to extract light guided along the extraction waveguide in the second direction towards an eye of a viewer, the array of extraction features being distributed along the extraction waveguide so as to provide exit pupil expansion, and
• the transverse anamorphic component comprises:
• a partially reflective surface;
• a reflective linear polariser disposed in series with the partially reflective surface, wherein at least one of the partially reflective surface and the reflective linear polariser has positive optical power in the transverse direction;
• and
• a polarisation conversion retarder disposed between the partially reflective surface and the reflective linear polariser, the polarisation conversion retarder being arranged to convert a polarisation state of light passing therethrough between a linear polarisation state and a circular polarisation state.

An anamorphic near-eye display apparatus comprising:

• an illumination system comprising a spatial light modulator, the illumination system being arranged to output light;
• and
• an optical system arranged to direct light from the illumination system to a viewer's eye, wherein the optical system has an optical axis and has anamorphic properties in a lateral direction and a transverse direction that are perpendicular to each other and perpendicular to the optical axis, wherein the spatial light modulator comprises pixels distributed in the lateral direction, and the optical system comprises:
• a transverse anamorphic component having positive optical power in the transverse direction, wherein the transverse anamorphic component is arranged to receive light from the spatial light modulator and the illumination system is arranged so that light output from the transverse anamorphic component is directed in directions that are distributed in the transverse direction;
• an extraction waveguide arranged to receive light from the transverse anamorphic component;
• a lateral anamorphic component having positive optical power in the lateral direction, the extraction waveguide being arranged to guide light from the transverse anamorphic component to the lateral anamorphic component along the extraction waveguide in a first direction;
• and
• a light reversing reflector that is arranged to reflect light that has been guided along the extraction waveguide in the first direction so that the reflected light is guided along the extraction waveguide in a second direction opposite to the first direction,
• wherein
• the extraction waveguide comprises an array of extraction features, the extraction features being arranged to transmit light guided along the extraction waveguide in the first direction and to extract light guided along the extraction waveguide in the second direction towards an eye of a viewer, the array of extraction features being distributed along the extraction waveguide so as to provide exit pupil expansion, and
• wherein the lateral anamorphic component comprises a lens formed by at least one surface of an air gap formed in a waveguide.

An anamorphic near-eye display apparatus comprising:

• an illumination system comprising a spatial light modulator, the illumination system being arranged to output light;
• and
• an optical system arranged to direct light from the illumination system to a viewer's eye, wherein the optical system has an optical axis and has anamorphic properties in a lateral direction and a transverse direction that are perpendicular to each other and perpendicular to the optical axis, wherein the spatial light modulator comprises pixels distributed in the lateral direction, and the optical system comprises:
• a transverse anamorphic component having positive optical power in the transverse direction, wherein the transverse anamorphic component is arranged to receive light from the spatial light modulator and the illumination system is arranged so that light output from the transverse anamorphic component is directed in directions that are distributed in the transverse direction;
• an extraction waveguide arranged to receive light from the transverse anamorphic component;
• a lateral anamorphic component having positive optical power in the lateral direction, the extraction waveguide being arranged to guide light from the transverse anamorphic component to the lateral anamorphic component along the extraction waveguide in a first direction;
• and
• a light reversing reflector that is arranged to reflect light that has been guided along the extraction waveguide in the first direction so that the reflected light is guided along the extraction waveguide in a second direction opposite to the first direction,
• wherein
• the extraction waveguide comprises an array of extraction features, the extraction features being arranged to transmit light guided along the extraction waveguide in the first direction and to extract light guided along the extraction waveguide in the second direction towards an eye of a viewer, the array of extraction features being distributed along the extraction waveguide so as to provide exit pupil expansion, and
• the lens of the lateral anamorphic component is a Pancharatnam-Berry lens.

An anamorphic near-eye display apparatus comprising:

• an illumination system comprising a spatial light modulator, the illumination system being arranged to output light;
• and
• an optical system arranged to direct light from the illumination system to a viewer's eye, wherein the optical system has an optical axis and has anamorphic properties in a lateral direction and a transverse direction that are perpendicular to each other and perpendicular to the optical axis, wherein the spatial light modulator comprises pixels distributed in the lateral direction, and the optical system comprises:
• a transverse anamorphic component having positive optical power in the transverse direction, wherein the transverse anamorphic component is arranged to receive light from the spatial light modulator and the illumination system is arranged so that light output from the transverse anamorphic component is directed in directions that are distributed in the transverse direction;
• an extraction waveguide arranged to receive light from the transverse anamorphic component;
• a lateral anamorphic component having positive optical power in the lateral direction, the extraction waveguide being arranged to guide light from the transverse anamorphic component to the lateral anamorphic component along the extraction waveguide in a first direction;
• and
• a light reversing reflector that is arranged to reflect light that has been guided along the extraction waveguide in the first direction so that the reflected light is guided along the extraction waveguide in a second direction opposite to the first direction,
• wherein
• the extraction waveguide comprises an array of extraction features, the extraction features being arranged to transmit light guided along the extraction waveguide in the first direction and to extract light guided along the extraction waveguide in the second direction towards an eye of a viewer, the array of extraction features being distributed along the extraction waveguide so as to provide exit pupil expansion, and
• at least one of an input end of the extraction waveguide, the transverse anamorphic component and the spatial light modulator has a curvature in the lateral direction that compensates for field curvature of the lateral anamorphic component.

An anamorphic near-eye display apparatus comprising:

• an illumination system comprising a spatial light modulator, the illumination system being arranged to output light;
• and
• an optical system arranged to direct light from the illumination system to a viewer's eye, wherein the optical system has an optical axis and has anamorphic properties in a lateral direction and a transverse direction that are perpendicular to each other and perpendicular to the optical axis, wherein the spatial light modulator comprises pixels distributed in the lateral direction, and the optical system comprises:
• a transverse anamorphic component having positive optical power in the transverse direction, wherein the transverse anamorphic component is arranged to receive light from the spatial light modulator and the illumination system is arranged so that light output from the transverse anamorphic component is directed in directions that are distributed in the transverse direction;
• an extraction waveguide arranged to receive light from the transverse anamorphic component;
• a lateral anamorphic component having positive optical power in the lateral direction, the extraction waveguide being arranged to guide light from the transverse anamorphic component to the lateral anamorphic component along the extraction waveguide in a first direction;
• and
• a light reversing reflector that is arranged to reflect light that has been guided along the extraction waveguide in the first direction so that the reflected light is guided along the extraction waveguide in a second direction opposite to the first direction,
• wherein
• the extraction waveguide comprises an array of extraction features, the extraction features being arranged to transmit light guided along the extraction waveguide in the first direction and to extract light guided along the extraction waveguide in the second direction towards an eye of a viewer, the array of extraction features being distributed along the extraction waveguide so as to provide exit pupil expansion, and
• the spatial light modulator comprises an array of pixels, wherein each pixel comprises sub-pixels of plural colour components and a pitch of the sub-pixels of each colour component across the pixels in the lateral direction varies between the colour components in a manner that compensates for chromatic aberration between light of the colour components.

An anamorphic directional illumination device comprising:

• an illumination system comprising a light source array, the illumination system being arranged to output light;
• and
• an optical system arranged to direct light from the illumination system, wherein the optical system has an optical axis and has anamorphic properties in a lateral direction and a transverse direction that are perpendicular to each other and perpendicular to the optical axis, wherein the light source array comprises light sources distributed in the lateral direction, and the optical system comprises:
• a transverse anamorphic component having positive optical power in the transverse direction, wherein the transverse anamorphic component is arranged to receive light from the light source array and the illumination system is arranged so that light output from the transverse anamorphic component is directed in directions that are distributed in the transverse direction;
• an extraction waveguide arranged to receive light from the transverse anamorphic component;
• a lateral anamorphic component having positive optical power in the lateral direction, the extraction waveguide being arranged to guide light from the transverse anamorphic component to the lateral anamorphic component along the extraction waveguide in a first direction;
• and
• a light reversing reflector that is arranged to reflect light that has been guided along the extraction waveguide in the first direction so that the reflected light is guided along the extraction waveguide in a second direction opposite to the first direction,
• wherein
• the extraction waveguide comprises at least one extraction feature, the at least one extraction feature being arranged to transmit light guided along the extraction waveguide in the first direction and to extract light guided along the extraction waveguide in the second direction, and
• the lateral anamorphic component comprises:
• a reflective linear polariser disposed between the light reversing reflector and the at least one extraction feature;
• and
• a polarisation conversion retarder disposed between the reflective linear polariser and the light reversing reflector, the polarisation conversion retarder being arranged to convert a polarisation state of light passing therethrough between a linear polarisation state and a circular polarisation state.

An anamorphic directional illumination device comprising:

• an illumination system comprising a light source array, the illumination system being arranged to output light;
• and
• an optical system arranged to direct light from the illumination system, wherein the optical system has an optical axis and has anamorphic properties in a lateral direction and a transverse direction that are perpendicular to each other and perpendicular to the optical axis, wherein the light source array comprises light sources distributed in the lateral direction, and the optical system comprises:
• a transverse anamorphic component having positive optical power in the transverse direction, wherein the transverse anamorphic component is arranged to receive light from the light source array and the illumination system is arranged so that light output from the transverse anamorphic component is directed in directions that are distributed in the transverse direction;
• an extraction waveguide arranged to receive light from the transverse anamorphic component;
• a lateral anamorphic component having positive optical power in the lateral direction, the extraction waveguide being arranged to guide light from the transverse anamorphic component to the lateral anamorphic component along the extraction waveguide in a first direction;
• and
• a light reversing reflector that is arranged to reflect light that has been guided along the extraction waveguide in the first direction so that the reflected light is guided along the extraction waveguide in a second direction opposite to the first direction,
• wherein
• the extraction waveguide comprises at least one extraction feature, the at least one extraction feature being arranged to transmit light guided along the extraction waveguide in the first direction and to extract light guided along the extraction waveguide in the second direction, and
• the transverse anamorphic component comprises:
• a partially reflective surface;
• a reflective linear polariser disposed in series with the partially reflective surface, wherein at least one of the partially reflective surface and the reflective linear polariser has positive optical power in the transverse direction;
• and
• a polarisation conversion retarder disposed between the partially reflective surface and the reflective linear polariser, the polarisation conversion retarder being arranged to convert a polarisation state of light passing therethrough between a linear polarisation state and a circular polarisation state.

An anamorphic directional illumination device comprising:

• an illumination system comprising a light source array, the illumination system being arranged to output light;
• and
• an optical system arranged to direct light from the illumination system, wherein the optical system has an optical axis and has anamorphic properties in a lateral direction and a transverse direction that are perpendicular to each other and perpendicular to the optical axis, wherein the light source array comprises light sources distributed in the lateral direction, and the optical system comprises:
• a transverse anamorphic component having positive optical power in the transverse direction, wherein the transverse anamorphic component is arranged to receive light from the light source array and the illumination system is arranged so that light output from the transverse anamorphic component is directed in directions that are distributed in the transverse direction;
• an extraction waveguide arranged to receive light from the transverse anamorphic component;
• a lateral anamorphic component having positive optical power in the lateral direction, the extraction waveguide being arranged to guide light from the transverse anamorphic component to the lateral anamorphic component along the extraction waveguide in a first direction;
• and
• a light reversing reflector that is arranged to reflect light that has been guided along the extraction waveguide in the first direction so that the reflected light is guided along the extraction waveguide in a second direction opposite to the first direction,
• wherein
• the extraction waveguide comprises at least one extraction feature, the at least one extraction feature being arranged to transmit light guided along the extraction waveguide in the first direction and to extract light guided along the extraction waveguide in the second direction, and
• wherein the lateral anamorphic component comprises a lens formed by at least one surface of an air gap formed in a waveguide.

An anamorphic directional illumination device comprising:

• an illumination system comprising a light source array, the illumination system being arranged to output light;
• and
• an optical system arranged to direct light from the illumination system, wherein the optical system has an optical axis and has anamorphic properties in a lateral direction and a transverse direction that are perpendicular to each other and perpendicular to the optical axis, wherein the light source array comprises light sources distributed in the lateral direction, and the optical system comprises:
• a transverse anamorphic component having positive optical power in the transverse direction, wherein the transverse anamorphic component is arranged to receive light from the light source array and the illumination system is arranged so that light output from the transverse anamorphic component is directed in directions that are distributed in the transverse direction;
• an extraction waveguide arranged to receive light from the transverse anamorphic component;
• a lateral anamorphic component having positive optical power in the lateral direction, the extraction waveguide being arranged to guide light from the transverse anamorphic component to the lateral anamorphic component along the extraction waveguide in a first direction;
• and
• a light reversing reflector that is arranged to reflect light that has been guided along the extraction waveguide in the first direction so that the reflected light is guided along the extraction waveguide in a second direction opposite to the first direction,
• wherein
• the extraction waveguide comprises at least one extraction feature, the at least one extraction feature being arranged to transmit light guided along the extraction waveguide in the first direction and to extract light guided along the extraction waveguide in the second direction, and
• the lens of the lateral anamorphic component is a Pancharatnam-Berry lens.

An anamorphic directional illumination device comprising:

• an illumination system comprising a light source array, the illumination system being arranged to output light;
• and
• an optical system arranged to direct light from the illumination system, wherein the optical system has an optical axis and has anamorphic properties in a lateral direction and a transverse direction that are perpendicular to each other and perpendicular to the optical axis, wherein the light source array comprises light sources distributed in the lateral direction, and the optical system comprises:
• a transverse anamorphic component having positive optical power in the transverse direction, wherein the transverse anamorphic component is arranged to receive light from the light source array and the illumination system is arranged so that light output from the transverse anamorphic component is directed in directions that are distributed in the transverse direction;
• an extraction waveguide arranged to receive light from the transverse anamorphic component;
• a lateral anamorphic component having positive optical power in the lateral direction, the extraction waveguide being arranged to guide light from the transverse anamorphic component to the lateral anamorphic component along the extraction waveguide in a first direction;
• and
• a light reversing reflector that is arranged to reflect light that has been guided along the extraction waveguide in the first direction so that the reflected light is guided along the extraction waveguide in a second direction opposite to the first direction,
• wherein
• the extraction waveguide comprises at least one extraction feature, the at least one extraction feature being arranged to transmit light guided along the extraction waveguide in the first direction and to extract light guided along the extraction waveguide in the second direction, and
• at least one of an input end of the extraction waveguide, the transverse anamorphic component and the light source array has a curvature in the lateral direction that compensates for field curvature of the lateral anamorphic component.

An anamorphic directional illumination device comprising:

• an illumination system comprising a light source array, the illumination system being arranged to output light;
• and
• an optical system arranged to direct light from the illumination system, wherein the optical system has an optical axis and has anamorphic properties in a lateral direction and a transverse direction that are perpendicular to each other and perpendicular to the optical axis, wherein the light source array comprises light sources distributed in the lateral direction, and the optical system comprises:
• a transverse anamorphic component having positive optical power in the transverse direction, wherein the transverse anamorphic component is arranged to receive light from the light source array and the illumination system is arranged so that light output from the transverse anamorphic component is directed in directions that are distributed in the transverse direction;
• an extraction waveguide arranged to receive light from the transverse anamorphic component;
• a lateral anamorphic component having positive optical power in the lateral direction, the extraction waveguide being arranged to guide light from the transverse anamorphic component to the lateral anamorphic component along the extraction waveguide in a first direction;
• and
• a light reversing reflector that is arranged to reflect light that has been guided along the extraction waveguide in the first direction so that the reflected light is guided along the extraction waveguide in a second direction opposite to the first direction,
• wherein
• the extraction waveguide comprises at least one extraction feature, the at least one extraction feature being arranged to transmit light guided along the extraction waveguide in the first direction and to extract light guided along the extraction waveguide in the second direction, and
• the light source array comprises an array of light sources, wherein each light source comprises sub-light sources of plural colour components and a pitch of the sub-light sources of each colour component across the light sources in the lateral direction varies between the colour components in a manner that compensates for chromatic aberration between light of the colour components.