Abstract: A lithographic mask is illuminated with light from different directions such that intensities of a plurality of incident beams of light provide a largest possible integrated process window defined in terms of an allowed range for defining shapes. Constrained sets of intensity parameters are imposed. A first set of intensity parameters represents maximum possible intensities that can be permitted for overexposed tolerance positions. A second set of intensity parameters represents minimum possible intensities that can be permitted for underexposed tolerance positions. Optimum source intensities of incident beams are defined using a linear program and constraints. The optimum source intensities maximize an integrated range of dose and focal variations without causing printed shapes to depart from the allowed range. Apparatus are detailed and variations are described.

Abstract: Disclosed is a method for illuminating a lithographic mask with light from different directions, in such a way that the intensities of the various incident beams provide the largest possible integrated process window. The process window is defined in terms of allowable ranges for printed shapes. For example, boundaries of the process window may be defined by shape limits corresponding to underexposed and overexposed conditions. Intensity parameters for representing the maximum possible intensities that can be permitted for overexposed tolerance positions are imposed through application of various constraints. Another set of intensity parameters for representing the minimum possible intensities that can be permitted for underexposed tolerance positions are imposed through application of various constraints. One parameter of each kind is defined for each of a number of different focal ranges. The optimum source intensities are determined from a linear program involving these and other constraints.

Abstract: A lithographic mask is illuminated with light from different directions such that intensities of a plurality of incident beams of light provide a largest possible integrated process window defined in terms of an allowed range for defining shapes. Constrained sets of intensity parameters are imposed. A first set of intensity parameters represents maximum possible intensities that can be permitted for overexposed tolerance positions. A second set of intensity parameters represents minimum possible intensities that can be permitted for underexposed tolerance positions. Optimum source intensities of incident beams are defined using a linear program and constraints. The optimum source intensities maximize an integrated range of dose and focal variations without causing printed shapes to depart from the allowed range. Apparatus are detailed and variations are described.

Abstract: A lithographic mask is illuminated with light from different directions such that intensities of a plurality of incident beams of light provide a largest possible integrated process window defined in terms of an allowed range for defining shapes. Constrained sets of intensity parameters are imposed. A first set of intensity parameters represents maximum possible intensities that can be permitted for overexposed tolerance positions. A second set of intensity parameters represents minimum possible intensities that can be permitted for underexposed tolerance positions. Optimum source intensities of incident beams are defined using a linear program and constraints. The optimum source intensities maximize an integrated range of dose and focal variations without causing printed shapes to depart from the allowed range. Apparatus are detailed and variations are described.

Abstract: A method is provided for optimizing the number of kernels N used in a sum of coherent sources (SOCS) for optical proximity correction in an optical microlithography process, including setting the number of kernels N to a predetermined minimum value Nmin, where a determination is made as to whether an accuracy estimate of calculated intensity is within a tolerable value, and a determination is also made as to whether an added X/Y asymmetry estimate of the calculated intensity is negligible.

Abstract: A lithographic mask is illuminated with light from different directions such that intensities of a plurality of incident beams of light provide a largest possible integrated process window defined in terms of an allowed range for defining shapes. Constrained sets of intensity parameters are imposed. A first set of intensity parameters represents maximum possible intensities that can be permitted for overexposed tolerance positions. A second set of intensity parameters represents minimum possible intensities that can be permitted for underexposed tolerance positions. Optimum source intensities of incident beams are defined using a linear program and constraints. The optimum source intensities maximize an integrated range of dose and focal variations without causing printed shapes to depart from the allowed range. Apparatus are detailed and variations are described.

Abstract: A reflective liquid crystal lightvalve for modulating the polarization of incident light within a specified band of wavelengths into on and off states, comprises: (i) a pixelated reflective backplane; (ii) a first liquid crystal layer, positioned proximate the pixelated reflective backplane, the first liquid crystal layer being tuned in the off state to switch incident light at the center of the specified band of wavelengths into a state that is not fully off; and (iii) a second liquid crystal layer, positioned proximate the first liquid crystal layer wherein the first liquid crystal layer is positioned between the second liquid crystal layer and the pixelated reflective backplane, the second liquid crystal layer having a birefringence which, at a given depth within its thickness, is substantially equal and opposite to a birefringence of a layer within the first liquid crystal layer that is located at a matching distance from a midplane separating the first and second liquid crystal layers.

Abstract: A projection display system includes a light source, wavelength-selective retarder device, first and second reflective light valves (LVs), a polarizing beam splitter (PBS), and a wavelength-selective filtering device. The wavelength-selective retarder device receives a uniformly polarized light from the light source and produces a first dark-state light having a first polarization state at a first set of wavelengths and a second dark-state light having a second polarization state at a second set of wavelengths. The first LV receives the first dark-state light and produces a first bright-state light by rotating the polarization from the first polarization state to the second polarization state. The second LV receives the second dark-state light and produces a second bright-state light by rotating the polarization from the second polarization state to the first polarization state.

Abstract: A projection display for displaying a color image formed of a plurality of color pixels. Each color pixel has a combination of different color light components. The display has a light source for supplying light to an optical path. A projection lens is disposed in the optical path, as are first and second light valves. The first and second light valves each have a plurality of subpixels. Each subpixel has an associated color filter for reflecting a corresponding color light component. The sub-pixels are grouped into groups of three, each group has a single sub-pixel from one of the first or second light valves and the remaining two sub-pixels from the other light valve, which together combine to form a color pixel of the color image for each of the color pixels of the color image.

Abstract: An apparatus for polarization conversion having a light source for supplying vertically and horizontally linearly polarized light to an optical path and a parabolic mirror disposed in the optical path and proximate to the light source. In different embodiments, the parabolic mirror has a mirror coating to induce a phase shift of 0°, 90°, or an arbitrary phase shift between incident light and reflected light. A polarizer means, preferably a reflective polarizer film, is disposed in the optical path for reflecting light of one of the linear polarizations and for transmitting the other linear polarization. Lastly, one or more waveplates are disposed in the optical path between the polarizer means and the parabolic mirror. The waveplates have opposing segments each having axes which are antiparallel to each other for recycling the reflected linear polarization by converting it to the transmitted polarization.

Abstract: A projection display for displaying a color image formed of a plurality of color pixels. Each color pixel has a combination of different color light components. The display has a light source for supplying light to an optical path. A projection lens is disposed in the optical path, as are first and second light valves. The first and second light valves each have a plurality of subpixels. Each subpixel has an associated color filter for reflecting a corresponding color light component. The sub-pixels are grouped into groups of three, each group has a single subpixel from one of the first or second light valves and the remaining two sub-pixels from the other light valve, which together combine to form a color pixel of the color image for each of the color pixels of the color image.

Abstract: An illumination apparatus including: at least two light sources, in which each of the light sources produce independent light beams; a controller for sequentially driving each of the light sources at a high power above their respective maximum rated power, to produce a respective light beam for each light source, and for leaving the remaining light sources at a low power below their respective maximum rated power, such that the time-average of the high and low power levels are set to a predetermined value for each of the light sources; and a combiner and director for sequentially combining each of the light beams from their respective light sources while being driven at high power into a common output beam with a fixed direction. Various combiner and directors are disclosed including tiltable mirrors under the control of the controller as well as optical systems.

Abstract: The present invention describes a method and an apparatus for eliminating image artifacts due to imaging of post spacers, or other small clusters of pixels that deviate from nominal performance of light valve technology. This invention is applicable to imaging technologies whose pixels are separately addressable.

Abstract: An illumination apparatus including: at least two light sources, in which each of the light sources produce independent light beams; a controller for sequentially driving each of the light sources at a high power above their respective maximum rated power, to produce a respective light beam for each light source, and for leaving the remaining light sources at a low power below their respective maximum rated power, such that the time-average of the high and low power levels are set to a predetermined value for each of the light sources; and a combiner and director for sequentially combining each of the light beams from their respective light sources while being driven at high power into a common output beam with a fixed direction. Various combiner and directors are disclosed including tiltable mirrors under the control of the controller as well as optical systems.

Abstract: An optical system for a projection display includes one or more polarizing beam splitters, one or more reflective light valves disposed to receive light transmitted through the one or more splitters and one or more phase correcting members, each disposed between the one or more splitters and the one or more light valves, whereby contrast of the display is substantially improved.

Abstract: The present invention describes a method and an apparatus for eliminating image artifacts due to imaging of post spacers, or other small clusters of pixels that deviate from nominal performance of light valve technology. This invention is applicable to imaging technologies whose pixels are separately addressable.

Abstract: An apparatus for polarization conversion having a light source for supplying vertically and horizontally linearly polarized light to an optical path and a parabolic mirror disposed in the optical path and proximate to the light source. In different embodiments, the parabolic mirror has a mirror coating to induce a phase shift of 0.degree., 90.degree., or an arbitrary phase shift between incident light and reflected light. A polarizer, preferably a reflective polarizer film, is disposed in the optical path for reflecting light of one of the linear polarizations and for transmitting the other linear polarization. Lastly, one or more waveplates are disposed in the optical path between the polarizer and the parabolic mirror. The waveplates have opposing segments each having axes which are antiparallel to each other for recycling the reflected linear polarization by converting it to the transmitted polarization.

Abstract: An optical element useful in optical systems such as liquid crystal optical display devices which is capable of projecting images having a high degree of contrast is provided. The optical element comprises a set of prisms whose coatings are designed to cancel one component of the depolarization in the light the prisms deliver. The other depolarization component is removed by returning the light to the projection lens through the same sequence of color-dividing coatings in reverse order. Hence, the optical element eliminates the depolarization components by employing double-pass propagation of polarized light therethrough.

Abstract: A display is disclosed operating in a field-sequential color mode having first and second light valves which are simultaneously illuminated with different color beams having different polarizations provided from a color wheel. The light valves provide an image forming light to a projection lens for projecting the image forming light onto a screen. The wheel has front and back surfaces which are displaced from each other and have segments of different colors for separating a polarized white light into the simultaneous different color beams. A retardation film for converting the polarization of colors reflected from the back surface from a first polarization to a second polarization. The wheel is rotated for sequentially illuminating the light valves with different colors of different polarizations simultaneously.

Abstract: An optical system is described consisting of reflection birefringent light valves, polarizing beam splitter, color image combining prisms, illumination system, projection lens, filters for color and contrast control, and screen placed in a configuration offering advantages for a high resolution color display. The system includes a quarter wave plate positioned to suppress stray reflection from the projection lens. The system also includes a second quarter wave plate disposed on the screen and a polarizing film disposed on the second quarter wave plate to suppress ambient light from illuminating the screen and entering the system.