Abstract: A liquid crystal panel and method are disclosed for increasing optical efficiency in the panel by using a reflector with a high fill factor and arranging an array of transparent pixel electrodes between the reflector and a layer of liquid crystal.

Abstract: A gamma variation of image intensity is created by varying the illumination intensity during a pulse width modulated display time period. During the pulse width modulated display time period a ramp signal may be compared with the image data to determine when pixel electrodes of the pixel array are switched. The illumination intensity may be varied in concert with ramp signal to produce a quadratic variation of displayed intensity on image data value. The illumination source could be an LED illumination source and intensity of the LED illumination source could be controlled using pulse width modulation.

Abstract: Disclosed are illumination systems especially suitable for very small data projectors, called pico projectors. The disclosed illumination systems provide high optical efficiency for projectors that need polarized light but utilize unpolarized light sources such as light-emitting diodes. Some of the disclosed illumination systems make use of light sources of different colors, and provide polarization conversion in ways based on color-selective elements of a variety of different types to convert substantially all the light emitted by the light sources to a single polarization, without increasing the effective optical extent of the source. Other disclosed illumination system provide compact ways to combine light from differently colored light sources without the use of bulky x-cube or angled dichroic elements.

Abstract: A digital display with image data storage memory that minimizes the impact of defective memory cells by remapping stored image data. Memory defects may be detected by automatic or visual testing. The digital display may perform a mapping process such that image data placed in the location of the defective storage cells is based on the significance of the data, both by bit and by color. The mapping process may operate on addressed rows of memory cells of the digital display.

Abstract: Disclosed are display systems using reflective liquid-crystal microdisplays that efficiently use unpolarized light sources without needing to double the étendue of the source as occurs with conventional polarization conversion systems. Furthermore, the display systems can utilize on-axis projection lenses, and fast-switching ferroelectric-liquid-crystal-on-silicon (FLCOS) microdisplays. The systems utilize beam splitters that split unpolarized incident light into two diverged beams of opposite polarization. Ferroelectric liquid crystal display elements are combined with fixed retarders to enable an element that can selectively flip or not flip the handedness of incident circularly polarized light.

Abstract: A digital display provides pulse-width-modulated pixel waveforms by applying a wired-NOR function to selected bits of stored image data. Image bits are selected according to a digital sequence and the wired-NOR function results in a trigger signal that may be used to switch the state of a pixel element. The pixel element may be a pixel state latch of a pixel driver circuit. The digital display may accept conventional 24-bit color video signals (one 8-bit gray-scale value for each pixel for each of the red, green, and blue primary colors), and convert this input signal to sequential color with PWM digital gray scale drive to each pixel.

Abstract: A holographic data storage system that includes a write head that includes a pixellated spatial light modulator and a separate or integral phase mask that varies the phase depending on the location in the phase mask that light passes through. The phase variation can be changed over time in a random, pseudo-random, or predetermined fashion. The spatial light modulator and phase mask can be implemented in a liquid crystal SLM (nematic, ferroeleletric, or other), in a DMD SLM, in a magneto-optical SLM, or in any other suitable manner.

Abstract: A system for producing spatially modulated monochrome or color light having gray scale includes an active matrix liquid crystal spatial light modulator having light modulating means including (i) a layer of ferroelectric liquid crystal material which is designed to switch between ON and OFF states and (ii) active matrix means including VLSI circuitry for dividing the layer of liquid crystal material into an array of individual liquid crystal pixels and for causing each of the pixels of liquid crystal material to modulate light individually by switching between the ON and OFF states in a way that depends upon the data which the VLSI circuitry is written. The system also includes illumination means having a light source for directing light from the source into the pixel-divided layer of ferroelectric liquid crystal material in a specific way.

Abstract: A system for producing modulated lights disclosed. The system comprises a spatial light modulator including a light modulating medium switchable between different states so as to act on light in ways which form overall patterns of modulated light. The system also includes an arrangement for switching the modulating medium between the different states in a controlled way and an illumination arrangement for producing a source of light. The system, further includes an optics arrangement for directing light from the source of light into the spatial light modulator and for directing light from the spatial light modulator through a predetermined source imaging area. The optics arrangement cooperates with the illumination arrangement and the spatial light modulator so as to produce a real image of the source of light within the source imaging area such that an individual is able to view a virtual image of the overall patterns of modulated light from the source imaging area.

Abstract: A spatial light modulator (SLM) having a phase mask that is provided as an internal component thereof. The phase mask can be provided as a multilevel surface of relatively higher index of refraction material on an inner surface of a transmissive cover window or as a separate transmissive window between the cover window and the pixels of the SLM. If the phase mask is to be used with a liquid crystal SLM, then it may be desirable to planarize the surface of the cover window contacting the liquid crystal by providing a layer of relatively lower index of refraction material adjacent the multilevel surface. The phase mask can also be provided on the transmissive cover window by patterned ion deposition, exposing patterned light to a photopolymeric material, or in some other suitable fashion. Arranging for the pixel electrodes to be at one of multiple levels rather than lying in an exactly planar relationship can also effectively create the phase mask.

Abstract: A display system that achieves a gamma characteristic different than 1, such as a gamma characteristic of 2 for example. The gamma characteristic may be selectable and it may be selectable via timing characteristics rather than by varying the intensity of the light source. Defective memory registers are also compensated for by selecting them to store bits of relatively lower significance.

Abstract: A gamma variation of image intensity is created by varying the illumination intensity during a pulse width modulated display time period. During the pulse width modulated display time period a ramp signal may be compared with the image data to determine when pixel electrodes of the pixel array are switched. The illumination intensity may be varied in concert with ramp signal to produce a quadratic variation of displayed intensity on image data value. The illumination source could be an LED illumination source and intensity of the LED illumination source could be controlled using pulse width modulation.

Abstract: A holographic data storage system that includes a write head that includes a pixellated spatial light modulator and a separate or integral phase mask that varies the phase depending on the location in the phase mask that light passes through. The phase variation can be changed over time in a random, pseudo-random, or predetermined fashion. The spatial light modulator and phase mask can be implemented in a liquid crystal SLM (nematic, ferroeleletric, or other), in a DMD SLM, in a magneto-optical SLM, or in any other suitable manner.

Abstract: Disclosed are display systems using reflective liquid-crystal microdisplays that efficiently use unpolarized light sources without needing to double the étendue of the source as occurs with conventional polarization conversion systems. Furthermore, the display systems can utilize on-axis projection lenses, and fast-switching ferroelectric-liquid-crystal-on-silicon (FLCOS) microdisplays. The systems utilize beam splitters that split unpolarized incident light into two diverged beams of opposite polarization. Ferroelectric liquid crystal display elements are combined with fixed retarders to enable an element that can selectively flip or not flip the handedness of incident circularly polarized light.

Abstract: A holographic data storage system that includes a write head that includes a pixellated spatial light modulator and a separate or integral phase mask that varies the phase depending on the location in the phase mask that light passes through. The phase variation can be changed over time in a random, pseudo-random, or predetermined fashion. The spatial light modulator and phase mask can be implemented in a liquid crystal SLM (nematic, ferroelectric, or other), in a DMD SLM, in a magneto-optical SLM, or in any other suitable manner.

Abstract: A frontlight illuminator arrangement for a reflective display that includes a light guide and a pair of light sources coupled to the light guide at an angle that is neither normal to or orthogonal to a primary axis of the display. The light is internally reflected along the light guide until it is coupled into an optical element of similar refractive index that is adjacent to the light guide in the vicinity of the display. The optical element includes a multi-faceted beam splitter that reflects light back through the light guide onto the display where an image is formed and reflected back through the light guide and beam splitter.

Abstract: Disclosed are illumination systems especially suitable for very small data projectors, called pico projectors. The disclosed illumination systems provide high optical efficiency for projectors that need polarized light but utilize unpolarized light sources such as light-emitting diodes. Some of the disclosed illumination systems make use of light sources of different colors, and provide polarization conversion in ways based on color-selective elements of a variety of different types to convert substantially all the light emitted by the light sources to a single polarization, without increasing the effective optical extent of the source. Other disclosed illumination system provide compact ways to combine light from differently colored light sources without the use of bulky x-cube or angled dichroic elements.

Abstract: A spatial light modulator (SLM) having a phase mask that is provided as an internal component thereof. The phase mask can be provided as a multilevel surface of relatively higher index of refraction material on an inner surface of a transmissive cover window or as a separate transmissive window between the cover window and the pixels of the SLM. If the phase mask is to be used with a liquid crystal SLM, then it may be desirable to planarize the surface of the cover window contacting the liquid crystal by providing a layer of relatively lower index of refraction material adjacent the multilevel surface. The phase mask can also be provided on the transmissive cover window by patterned ion deposition, exposing patterned light to a photopolymeric material, or in some other suitable fashion. Arranging for the pixel electrodes to be at one of multiple levels rather than lying in an exactly planar relationship can also effectively create the phase mask.

Abstract: A display system that achieves a gamma characteristic different than 1, such as a gamma characteristic of 2 for example. The gamma characteristic may be selectable and it may be selectable via timing characteristics rather than by varying the intensity of the light source. Defective memory registers are also compensated for by selecting them to store bits of relatively lower significance.

Abstract: A spatial light modulator (SLM) having a phase mask that is provided as an internal component thereof. The phase mask can be provided as a multilevel surface of relatively higher index of refraction material on an inner surface of a transmissive cover window or as a separate transmissive window between the cover window and the pixels of the SLM. If the phase mask is to be used with a liquid crystal SLM, then it may be desirable to planarize the surface of the cover window contacting the liquid crystal by providing a layer of relatively lower index of refraction material adjacent the multilevel surface. The phase mask can also be provided on the transmissive cover window by patterned ion deposition, exposing patterned light to a photopolymeric material, or in some other suitable fashion. Arranging for the pixel electrodes to be at one of multiple levels rather than lying in an exactly planar relationship can also effectively create the phase mask.