Configurations are disclosed for presenting virtual reality and augmented reality experiences to users. The system may comprise a lens assembly comprising two transmissive plates, a first of the two transmissive plates comprising a first surface sag based at least in part on a cubic function, and a DOE to direct image information to a user's eye; wherein the DOE is placed in between the two transmissive plates of the lens assembly, and wherein the DOE is encoded with the inverse of the cubic function corresponding to the surface sag of the first transmissive plate; such that a wavefront created by the encoded DOE is compensated by the wavefront created by the first transmissive plate, thereby collimating light rays associated with virtual content delivered to the DOE.

An eyepiece for projecting an image to an eye of a viewer includes a waveguide configured to propagate light in a first wavelength range, and a grating coupled to a back surface of the waveguide. The grating is configured to diffract a first portion of the light propagating in the waveguide out of a plane of the waveguide toward a first direction, and to diffract a second portion of the light propagating in the waveguide out of the plane of the waveguide toward a second direction opposite to the first direction. The eyepiece furthers include a wavelength-selective reflector coupled to a front surface of the waveguide. The wavelength selective reflector is configured to reflect light in the first wavelength range and transmit light outside the first wavelength range, such that the wavelength-selective reflector reflects at least part of the second portion of the light back toward the first direction.

An eyepiece includes a planar waveguide having a front surface and a back surface. The eyepiece also includes a grating coupled to the back surface of the planar waveguide and configured to diffract a first portion of the light propagating in the planar waveguide out of a plane of the planar waveguide toward a first direction and to diffract a second portion of the light propagating in the planar waveguide out of the plane of the planar waveguide toward a second direction opposite to the first direction and a wavelength-selective reflector coupled to the front surface of the planar waveguide. The wavelength-selective reflector comprises a multilevel metasurface comprising a plurality of spaced apart protrusions having a pitch and formed of a first optically transmissive material and a second optically transmissive material disposed between the spaced apart protrusions.

An optical probe includes a cylindrical lens adapted to receive and transmit incident light. A light-emitting surface of the cylindrical lens is a curved end surface having a concentric ring-shaped diffractive microstructure. A working position of the optical probe is a position where a diffraction order is 1 when the incident light having a design wavelength between a first wavelength and a second wavelength passes through the diffractive microstructure. When passing through the cylindrical lens, the incident light having the first wavelength produces a diffraction effect with the diffractive microstructure and is converged at a first wavelength working position approximately the same as the working position of the optical probe with the diffraction order of 1. After being refracted by the curved end surface, the incident light having the second wavelength is converged at a second wavelength working position approximately the same as the working position of the optical probe.

The image display device includes an image generating unit that emits first image light, a pupil expanding element that expands a diameter of a light flux included in the first image light from the image generating unit to obtain second image light, a first light condensing optical system that condenses the second image light and forms an intermediate image, and a second light condensing optical system that condenses light from the intermediate image and generates a virtual image on eye of a viewer, in a plane including at least the image generating unit, the pupil expanding element, and the eye of the viewer, a maximum emission angle of the first image light is smaller than a maximum viewing angle of the virtual image, and the diameter of the light flux included in the second image light is greater than that of a light flux included in the virtual image.

A meta lens assembly includes a first meta lens, a second meta lens arranged on an image side of the first meta lens, and a third meta lens arranged on an image side of the second meta lens, the first meta lens, the second meta lens, and the third meta lens being arranged from an object side of the meta lens assembly to an image side of the meta lens assembly facing an image sensor.

To overcome the problem of a diffractive surface having a large, and often excessively large, amount of chromatic aberration, an optical system can use multiple cascaded or sequential diffractive surfaces that, combined, have a reduced amount of chromatic aberration. The optical system can be designed such that all rays traversing the optical system and passing through the diffractive surfaces have an equal optical path length. In the design process, the sets of rays are identified, and the designs of the diffractive surfaces are selected to produce the angular deviations to produce the identified ray paths. In one example, an achromatic lens formed as two annular optical surfaces can receive a collimated incident beam, redirect rays helically at the first surface toward the second surface, and redirect the rays at the second surface toward a focal point. The azimuthal redirection can decrease with increasing distance away from a central axis.

A zoned waveplate has a series of transversely stacked birefringent zones alternating with non-birefringent zones. The birefringent and non-birefringent zones are integrally formed upon an AR-coated face of a single substrate by patterning the AR coated face of the substrate with zero-order sub-wavelength form-birefringent gratings configured to have a target retardance. The layer structure of the AR coating is designed to provide the target birefringence in the patterned zones and the reflection suppression.

An optical coupler device for coupling light with a light guide is provided. The device includes a first layer having a plurality of first diffraction gratings spaced apart via first trenches, the first diffraction gratings and the first trenches forming first periodic units. The device also includes a second layer having a plurality of second diffraction gratings spaced apart via second trenches, the second diffraction gratings and the second trenches forming second periodic units. Additionally, the second periodic units are offset in a lateral axis of the optical coupler device relative to the first periodic units by a relative shift distance S2 that is in a range from about 10 nm to about 600 nm.

A transmissive optical element may include a substrate. The transmissive optical element may include a first anti-reflectance structure for a particular wavelength range formed on the substrate. The transmissive optical element may include a second anti-reflectance structure for the particular wavelength range formed on the first anti-reflectance structure. The transmissive optical element may include a third anti-reflectance structure for the particular wavelength range formed on the second anti-reflectance structure. The transmissive optical element may include at least one layer disposed between the first anti-reflectance structure and the second anti-reflectance structure or between the second anti-reflectance structure and the third anti-reflectance structure.