An optical lens includes a first lens group with negative refractive power, a second lens group with positive refractive power, and an aperture stop disposed between the first lens group and the second lens group. A number of lenses with refractive power of the first lens group is smaller than three, and a number of lenses with refractive power of the second lens group is smaller than five. The second lens group has a lens with a diffractive optical surface, and the lens with a diffractive optical surface satisfies the condition: 0<|(d*V)/r|<2, where d denotes refractive power of the diffractive optical surface, r denotes refractive power of the lens, and V denotes an Abbe number of the lens with a diffractive optical surface.

A method of fabricating an optical device and the associated optical device are disclosed. The optical device includes a metasurface and a substrate that are integrally formed by the same materials. The method comprises: forming a photoresist mask on a substrate, the photoresist mask defining a metasurface pattern based on an optical profile of a target optical device; generating metasurface features on the substrate, by etching away a portion of the substrate that is not covered by the photoresist mask; and producing the target optical device having the metasurface features, by removing the photoresist mask, wherein the metasurface features include a portion of a material of the substrate.

A light redirecting film in a sandwich-laminated structure is provided. The light redirecting film comprises a first layer, a second layer; and an intermediate layer sandwiched between the first layer and the second layer. The intermediate layer includes a first grating surface having a plurality of first gratings extending in a first grating direction and a second grating surface opposite to the first grating surface having a plurality of second gratings extending in a second grating direction, wherein the first grating direction and the second grating direction cross each other at an angle of 9010, and the first grating surface and the second grating surface of the intermediate layer are gap-filled and planarized with the first layer and the second layer respectively to generate the light redirecting film.

A light redirecting film and a method for manufacturing the same are provided. The light redirecting film comprises a substrate, a first diffraction grating layer of a first curable resin on the substrate and a second diffraction grating layer of a second curable resin on the first diffraction grating layer. Wherein the grating directions of the first diffraction grating layer and the second diffraction grating layer cross each other at an angle of 9010, and the difference of the refractive index of the first curable resin and the second curable resin is no less than 0.1 and no more than 0.3.

An optical film includes a first diffraction layer, a second diffraction layer, and a cover layer. The first diffraction layer includes a plurality of first diffraction gratings arranged in a direction on a surface thereof. The second diffraction layer is filled in the gap of the first diffraction gratings of the first diffraction layer and forms a plurality of second diffraction gratings arranged in a direction on the first diffraction layer, wherein the directions of the first diffraction gratings and the second diffraction gratings are parallel to each other. The cover layer fills and planarizes the second diffraction gratings of the second diffraction layer. The optical film can reduce the light leakage defect of a conventional liquid crystal display in a wide viewing angle and make the liquid crystal display have a uniform dark-state image and color image quality.

An imaging lens structure and method of imaging are presented. The imaging lens structure comprising a lens region defining an effective aperture of the lens structure. The lens region comprises an arrangement of lens zones distributed within the lens region and comprising zones of at least two different optical functions differently affecting light passing therethrough. The zones of at least two different optical functions are arranged in an interlaced fashion along said lens region corresponding to a surface relief of the lens region such that adjacent lens zones of different optical functions are spaced apart from one another along an optical axis of the lens structure a distance larger than a coherence length of light at least one spectral range for which said lens structure is designed.

An optical processor is presented for applying optical processing to a light field passing through a predetermined imaging lens unit. The optical processor comprises a pattern in the form of spaced apart regions of different optical properties. The pattern is configured to define a phase coder, and a dispersion profile coder. The phase coder affects profiles of Through Focus Modulation Transfer Function (TFMTF) for different wavelength components of the light field in accordance with a predetermined profile of an extended depth of focusing to be obtained by the imaging lens unit. The dispersion profile coder is configured in accordance with the imaging lens unit and the predetermined profile of the extended depth of focusing to provide a predetermined overlapping between said TFMTF profiles within said predetermined profile of the extended depth of focusing.

An ophthalmological optical element, in particular a spectacle lens, includes a first refractive optical substrate, which has a positive or negative first optical power; a first diffractive optical element, which has a second optical power; and a second diffractive optical element, which has a third optical power. The first diffractive optical element and the second diffractive optical element have opposite optical powers. The first diffractive optical element and the second diffractive optical element interact in an at least partly achromatic manner.

A partial lens unit St includes one or more positive lenses that are appropriately set based on a focal length f.sub.1 of a first lens unit, a focal length f.sub.2 of a second lens unit, an overall lens length L, a focal length f of an imaging optical system of when focused on an infinite-distance object, a focal length f.sub.Pi of an i-th positive lens in an i-th position, among the positive lenses, counted in order from an object side to an image side, an Abbe number and an anomalous partial dispersion ratio difference .sub.dPi and .sub.gFPi of a material for the i-th positive lens, and the total number n of the positive lenses included in the one or more partial lens units St.

Provided is an optical system including, in order from an object side to an image side, a front lens unit, an aperture stop, and a rear lens unit. The front lens unit consists of a positive lens and a diffractive optical element, which are arranged in order from the object side to the image side. The diffractive optical element consists of a plurality of lenses that are cemented to each other, and at least one of cemented surfaces of the plurality of lenses is a diffractive surface. An interval on an optical axis between the positive lens and the diffractive optical element is the largest among intervals on the optical axis between two lenses that are adjacent in the optical system.