Abstract:
A method for designing a mask, the method includes: choosing or receiving a desired contrast value; and determining sizes, locations and shapes of multiple rotationally symmetric regions of a mask such as to define a modulation transfer function that is characterized by a substantially uniform response over a spatial frequency range; wherein the uniform response is substantially indifferent to an orientation of features of the object and to a location of the object within a deep depth-of-field region. An optical imaging system that includes: a mask that includes multiple rotationally regions; wherein the multiple rotationally symmetric regions are shaped and positioned such as to define a modulation transfer function that is characterized by a substantially uniform response over a spatial frequency range, wherein the uniform response is substantially indifferent to an orientation of features of the object and to a location of the object within a deep depth-of-field region
Abstract:
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.
Abstract:
Different distances of two or more objects in a scene being captured in a video conference are determined by determining a sharpest of two or more color channels and calculating distances based on the determining of the sharpest of the two or more color channels. At least one of the objects is identified as a foreground object or a background object, or one or more of each, based on the determining of the different distances. The technique involves blurring or otherwise rendering unclear at least one background object or one or more portions of the scene other than the at least one foreground object, or combinations thereof, also based on the determining of distances.
Abstract:
A method for designing a mask, the method includes: choosing or receiving a desired contrast value; and determining sizes, locations and shapes of multiple rotationally symmetric regions of a mask such as to define a modulation transfer function that is characterized by a substantially uniform response over a spatial frequency range; wherein the uniform response is substantially indifferent to an orientation of features of the object and to a location of the object within a deep depth-of-field region. An optical imaging system that includes: a mask that includes multiple rotationally regions; wherein the multiple rotationally symmetric regions are shaped and positioned such as to define a modulation transfer function that is characterized by a substantially uniform response over a spatial frequency range, wherein the uniform response is substantially indifferent to an orientation of features of the object and to a location of the object within a deep depth-of-field region
Abstract:
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.
Abstract:
The instant invention is an optical imaging system that produces images of acceptable quality of objects which are located at a wide variety of distances from the optical imaging system. A preferred embodiment of the optical imaging system includes an object (10), an auxiliary lens (12), a composite phase marsk (14) and a detector (18) arranged along an optical axis (20). Light from the object (10) is focused by the auxiliary lens (12) in tandem with the composite phase mark (14), producing an image (16) which is incident th detector (18).
Abstract:
Different distances of two or more objects in a scene being captured in a video conference are determined by determining a sharpest of two or more color channels and calculating distances based on the determining of the sharpest of the two or more color channels. At least one of the objects is identified as a foreground object or a background object, or one or more of each, based on the determining of the different distances. The technique involves blurring or otherwise rendering unclear at least one background object or one or more portions of the scene other than the at least one foreground object, or combinations thereof, also based on the determining of distances.