摘要:
A super-resolving imaging apparatus employs diffractive optical elements placed on the imaging lens. This element, and the use of a modified Scheimpflug arrangement allow the conversion of degrees of freedom in one axis of a field of view to a larger degree of freedom in another axis in order to obtain a high resolution image with a wide depth of focus and large field of view. Replicas created by the diffractive elements are mutually shifted by subpixel amounts, and are combined using a Gabor transform, which is facilitated by a spatial mask placed over the detector array. The apparatus is suitable for performing distance estimation on an object within the field of view.
摘要:
A method and system for synthesizing a desired light beam including calculating a two-dimensional light filter for an optical element, the two-dimensional light filter being such that the optical element produces under free space propagation, in response to illumination thereof, a three-dimensional light distribution that approximates the light distribution of the desired light beam, and illuminating the optical element.
摘要:
A phase-only filter for approximating a given optical transfer function for monochromatic incoherent light. The filter is designed by solving an integral equation for a phase function, and imposing, on a transparent plate, an optical path length for the incoherent radiation equal, in radians, to the phase function modulo 2.pi. plus an overall constant.
摘要:
A method for encoding zero-order phase-only holograms, and the holograms so encoded. The amplitude and phase of each point of a discrete mathematical transform, such as a Fourier transform, of an image to be encoded, are encoded as regions of a corresponding pixel of a transparent filter, with suitably selected fractional areas and optical path lengths. The various optical path lengths may be created by manipulating the filter's index of refraction, or by manipulating the thickness of the filter, preferably by etching. Various encoding schemes are presented, appropriate to etching systems with low lateral resolution, to etching systems with high lateral resolution but depth resolution limited to a discrete number of depths, and to etching systems with limited resolution both laterally and in depth.
摘要:
A method of optical element manufacturing, the method may include selecting a range of a misfocus parameter ψ; and designing the optical element to include multiple regions, wherein the optical transfer function (OTF) of the optical element allows, for the range of the misfocus parameter .psi., transmission of images with a contrast of at least 10% for all normalized spatial frequencies up to 50% of a theoretical maximum that is attainable with a full aperture in an in-focus condition.
摘要:
A method of optical element manufacturing, the method may include selecting a range of a misfocus parameter ψ; and designing the optical element to comprise multiple regions, wherein the optical transfer function (OTF) of the optical element allows, for the range of the misfocus parameter ψ, transmission of images with a contrast of at least 10% for all normalized spatial frequencies up to 50% of a theoretical maximum that is attainable with a full aperture in an in-focus condition.
摘要:
A mask for enhancing the depth of focus of an optical imaging system is designed by optimizing an optical property (transmittance or reflectance) of the mask relative to the intensity distribution in the system's image plane. Preferably, a desired PSF intensity is selected, a desired misfocus parameter range is selected, and the optical property is adjusted to minimize a measure of the departure of the system's PSF intensity, as computed from the mask's optical property, from the desired PSF intensity, over the entire misfocus parameter range. Most preferably, the desired PSF intensity is selected as the inverse Fourier transform of a desired OTF. Preferably, the mask is fabricated as a DOE.
摘要:
Scanner optics, usable for example in a bar code reader, generate a multitude of Gaussian beams derived from a common light source to produce a beam with extended working range. In the preferred embodiment, a 360 degree fan of Gaussian beams is generated by passing a laser beam through at least one diffractive element, e.g., computer generated holographic (CGH) plate, computed to perform the transformation of the illuminating beam into the desired output beam. The beam thus produced, having a small diameter over a large longitudinal distance, is useful for long range scanning.
摘要:
A method of extracting data from an identifiable monochromatic pattern. The method comprises separating a polychromatic optical signal, received from an object having identifiable monochromatic pattern, into a plurality of wavelength components, separately capturing each of the wavelength components, reconstructing a plurality of images each from a different wavelength component, detecting the identifiable monochromatic pattern in one or more of the images, and extracting data associated with or encoded by the detected identifiable monochromatic pattern. The images have different depths of field.
摘要:
A method of extracting data from an identifiable monochromatic pattern. The method comprises separating a polychromatic optical signal, received from an object having identifiable monochromatic pattern, into a plurality of wavelength components, separately capturing each of the wavelength components, reconstructing a plurality of images each from a different wavelength component, detecting the identifiable monochromatic pattern in one or more of the images, and extracting data associated with or encoded by the detected identifiable monochromatic pattern. The images have different depths of field.