A diffractive optical element including microstructures, along a surface of an optical material, having a phase profile to diffract input illumination into structured light of a plurality of different diffraction orders; wherein the phase profile is at least partially phase unwrapped is disclosed. Methods of generating the diffractive optical element is also disclosed.

An optical test method is provided. The optical test method includes emitting light through a gap between two substrates of a tested optical element disposed on a holder to generate a plurality of light beams. The optical test method further includes driving the holder with the tested optical element to move to N positions. The optical test method also includes receiving one of the light beams from the tested optical element in the N positions to generate N first intensity signals. In addition, the optical test method includes determining the size of the gap of the tested optical element according to the N first intensity signals and reference data.

A diffractive optical element for a structured light projection module and a method of using the diffractive optical element are described herein. The diffractive optical element is configured to: receive two-dimensional patterned beams and generate multi-order diffractive beams, wherein the two-dimensional patterned beams are emitted from a structured light projection module, the structured light projection module includes a light source comprising a plurality of sub-light sources arranged in a two-dimensional array, and the two-dimensional patterned beams correspond to the two-dimensional array; and project a plurality of two-dimensional patterned beams, wherein each of the plurality of two-dimensional patterned beams creates a corresponding duplicated pattern, and the duplicated patterns form a speckle pattern having uniform speckle density. The two-dimensional patterned beams can overlap with each other, or not overlap with each other.

An imaging device is presented for use in an imaging system capable of improving the image quality. The imaging device has one or more optical systems defining an effective aperture of the imaging device. The imaging device comprises a lens system having an algebraic representation matrix of a diagonalized form defining a first Condition Number, and a phase encoder utility adapted to effect a second Condition Number of an algebraic representation matrix of the imaging device, smaller than said first Condition Number of the lens system.

An method is provided including determining a first set of aperture patterns and a second set of aperture patterns for performing measurements with an imaging device such that for each aperture pattern in the first set of aperture patterns there exists a complementary aperture pattern in the second set of aperture patterns, wherein the imaging device comprises a sensor and an aperture assembly having a plurality of aperture elements; performing a measurement for each respective aperture pattern in the first set and in the second set by changing a property associated with one or more of the plurality of aperture elements in accordance with the respective aperture pattern; and processing the performed measurements to extract information about an image.

An imaging device is presented for use in an imaging system capable of improving the image quality. The imaging device has one or more optical systems defining an effective aperture of the imaging device. The imaging device comprises a lens system having an algebraic representation matrix of a diagonalized form defining a first Condition Number, and a phase encoder utility adapted to effect a second Condition Number of an algebraic representation matrix of the imaging device, smaller than said first Condition Number of the lens system.

An optical test method is provided. The optical test method includes emitting light through a gap between two substrates of a tested optical element disposed on a holder to generate a plurality of light beams. The optical test method further includes driving the holder with the tested optical element to move to N positions. The optical test method also includes receiving one of the light beams from the tested optical element in the N positions to generate N first intensity signals. In addition, the optical test method includes determining the size of the gap of the tested optical element according to the N first intensity signals and reference data.

A three dimensional image measurement system including a first optical system and a second optical system is provided. The first optical system is adapted to output a structural light beam and a zero order light beam. There is an angle between the structural light beam and the zero order light beam. The first optical system performs an optical operation to project the structural light beam to a three dimensional object to obtain three dimensional information of the three dimensional object. The second optical system is adapted to receive the zero order light beam and perform another optical operation by using the zero order light beam. The first optical system includes a plurality of optical elements. The value of the angle between the structural light beam and the zero order light beam is determined according to position parameters of the optical elements.

A wideband diffractive component diffracting an incident beam exhibiting a wavelength in a diffraction spectral band is provided. The diffractive component elementary areas are arranged on a surface, each area belonging to a type indexed by an index i lying between 1 and n, with n greater than 1, corresponding to blaze wavelength i of index i, the blaze wavelengths lying in the diffraction spectral band. An elementary area of type i includes microstructures sized less than 1.5 times the blaze wavelength of index i, arranged to form an artificial material exhibiting an effective index variation where an elementary area of type i constitutes a blazed diffractive element at the blaze wavelength i of index i, the different values of the blaze wavelengths and the proportion of surface area occupied by the areas of a given type a function of a global diffraction efficiency desired in the diffraction spectral band.

A method of performing coherent transformations of optical fields includes forming a far field distribution of the input optical field. A fraction of the formed far field is diffracted by producing localized discontinuities within said far field. A Fraunhofer diffraction pattern of the diffracted optical field is formed. The Fraunhofer diffraction pattern is modified by producing localized optical path differences within the Fraunhofer diffraction pattern. The transformed output optical field is produced in the far field with respect to the modified Fraunhofer diffraction pattern.