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 optimized design method for manufacturing a Fresnel grating is disclosed, including the following steps: (1) making a Fresnel surface type of the Fresnel grating equivalent to a curved surface type, and determining, based on the curved surface type to which the Fresnel surface type is equivalent, an optical path difference function of the Fresnel grating: ()=<AP.sub.1P.sub.2B><AOB>+Nm; and (2) determining a Fresnel grating parameter that minimizes a function value of the optical path difference function, so as to manufacture a Fresnel grating that has an aberration elimination effect. The manufactured Fresnel grating may effectively eliminate a portion of aberrations of the Fresnel grating, and increase a resolution of a spectrometer.

The invention is directed to a spectacle lens and includes a body which is transparent or at least partly transparent to light and has a phase object which guides the light incident at an angle of incidence on a side facing away from an observer into a direction depending on the wavelength of the light and the angle of incidence thereof. The phase object has a multiplicity of diffraction structures, which diffract monochromatic light at a wavelength of 380 nm800 nm with a diffraction efficiency of 70% into one and same order of diffraction |m|1 when the monochromatic light is incident at an angle of incidence on the side of the lens facing away from the observer which lies within a diffraction-structure-specific angle interval 15 wide and dependent on the wavelength of the light.

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.

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.

Although, conventionally, there were two methods, (1) a wave was transmitted through a spiral phase plate and (2) a diffraction grating containing an edge dislocation was used, they incurred complication of a configuration and securement of a larger amount of space and were not efficient because each of the spiral wave generation methods needed an incident wave to be a plane wave and at least one time of imaging is necessary at the time of wave irradiation on an observation object. In order to efficiently generate the spiral wave having a sufficient intensity, a structure of edge dislocation is taken in into a pattern of the zone plate and a spiral pattern containing a discontinuous zone is formed. Moreover, a thickness and a quality of material that change the phase of the wave by an odd multiple of are selected for a material of the wave-blocking section in the pattern.

A method for measuring the diameter of filament diffraction fringes by frequency domain calculation comprising: building a set of diffraction optical path measurement system and capturing diffraction fringe images; determining the starting point of the imaging range; Simulating the electromagnetic field propagation process in Fraunhofer diffraction, and determining the optimal fringe range considering the noise caused by the difference in CCD sensitivity; Finally calculating the filament diameter by Fourier transform for different lengths of fringe. The final value of the calculated filament diameter is obtained by fitting an envelope to the variation of the diameter. The invention is simple in calculation and has little dependence on the experimental device, which means the superiority of using the frequency domain for parameter measurement, and the measurement accuracy is in the sub-nanometer level. In addition, the invention proves the feasibility of extracting the fringe period information in the frequency domain.

A method of simulating the optical performance of a diffractive waveguide includes, generating a plurality of transfer matrices for each diffractive grating of the plurality of diffractive gratings responsive to performing a diffraction modeling process for a plurality of diffractive gratings of the waveguide based on a plurality of input light rays each having at least a different first characteristic. A plurality of electric fields at outcoupling positions of an outcoupling grating of the plurality of diffractive gratings is determined based on the plurality of transfer matrices responsive to performing a ray tracing process for multiple instances of each input light ray of the plurality of light rays with at least a different second characteristic. A uniformity map is generated for the waveguide based on the plurality of electric fields. The uniformity map indicates a uniformity of one or more characteristics of the waveguide across different sampled pupil positions.

An optical system includes a diffractive surface, and one or more non-planar refractive surfaces. The diffractive surface satisfies predetermined equations.

Complex spectral and angular diffractive optical elements in photosensitive materials based on Moir pattern are proposed and demonstrated. The process is based on the recording of multiple volume Bragg gratings with controlled difference of the periods in the same volume of photosensitive material. Filters with ultra-narrow bandpass in the range of a few picometers to a few tens of picometers or apodized diffractive optical elements across large aperture are demonstrated. Several methods to fabricating such Moir Bragg gratings are proposed. Experimental demonstration of a Moir ultra-narrowband diffractive optical element in PTR glass is performed.