摘要:
The present invention provides a polarization separation element comprising a first array of prisms having a wedge-shaped cross-section, and a second array of prisms also having a wedge-shaped cross section. One of the prism arrays is an array of birefringent prisms. The present invention also provides a polarization conversion system having a polarization separation element of the above type for directing light having a first polarization in a first direction and for directing light having a second polarization different from the first polarization in a second direction different from the first direction; and one or more polarization conversion elements for converting light having the first and second polarizations to light having a substantially common output polarization. The polarization conversion system of the invention is suitable for use in a projection display system.
摘要:
A display is provided for switching between a narrow or private viewing mode and a wide or public viewing mode. The display comprises a display device which is controlled to provide display of a desired image or sequence of images. This is associated with a liquid crystal device having at least one liquid crystal layer whose molecules are switchable between a first state providing a first angular viewing range and a second state providing a second angular viewing range which is within and smaller than the first angular viewing range. With the molecules in the second state, the device at least partially blocks light propagating towards part of the first angular viewing range outside the second angular viewing range. The or each liquid crystal layer is in contact with at least one alignment surface, the or each of which comprises a uniform non-patterned alignment surface.
摘要:
A directional backlight, a multiple view display and a multi-direction display A multiple view display (18) comprises a directional display device (19) for displaying a first image or sequence of images so as to be mainly visible from a first range of directions relative to the device and for simultaneously displaying a second image or sequence of images so as to be mainly visible from a second range of directions relative to the device different from the first range. The display (18) further comprises a directional backlight (20) for directing light through the display device (19) at least mainly in the first and second ranges. Since the directional backlight (20) directs light through the display device (19) at least mainly in the first and second ranges, the display provides users located in the first and second ranges with images of greater intensity than a conventional display. The backlight may be arranged to direct substantially no light in at least part of a third range of directions that lies between the first range of directions and the second range of directions. This provides a ‘black window’ between the first and second ranges in which the intensity of the display is lower than in other ranges. The intensity of the display in the black window is possibly zero, or close to zero, so that an observer located in this window will not perceive an image.
摘要:
A display is provided having private and public viewing modes. The display comprises a display device and a parallax optic (3) comprising an array of parallax elements (4). Each of the elements (4) co-operates with a set of pixels (1,2) having at least one first pixel (1) and at least one second pixel (2). A line (23) passing through the centre (21) of each first pixel (1) and the centre (22) of the cooperating parallax element (4) extends into a first viewing region (20a). The parallax elements (4) re-strict viewing of the first pixels (1) to the first viewing region and permit viewing of the second pixels (2) in a second viewing region. The display device displays a private image in the private viewing mode by means of only the first pixels (1) and displays a non-private image in the public viewing mode by means of at least the second pixels (2).
摘要:
An illumination system (32) is provided for producing output light having a variable angular illumination range for illuminating a display panel (31) in a display device (30). The illumination system (32) comprises first and second light sources (34 and 36) and is operable selectively in a first mode in which the output light comprises light derived from the first light source (34) with substantially no light derived from the second light source (36), and in a second mode in which the output light comprises light derived from at least the second light source (36). The output light derived from the first light source (34) has a first angular illumination range and the output light derived from the second light source (36) has a second angular illumination range wider than the first angular illumination range. The first mode can be used as a private mode and the second mode can be used as a public mode. The private mode can be used to prevent widespread reading of information or images displayed using the display device (30).
摘要:
A time-sequential colour projector comprises a pixellated light valve (2), such as a liquid crystal device, and a plurality of light sources (30, 31, 32). The light sources (30, 31, 32) direct light on different sets of pixels of the light valve (2) via an optical system (1), such as a lens array, which focuses the light on pixels of the light valve (2). At least two of the light sources (30, 31, 32) are multiple colour light sources and the multiple colour light sources emit different colour components during each set of frames making up a complete image frame.
摘要:
A display comprises a backlight (30, 45-48) and a spatial light modulator (1) such as a liquid crystal device for modulating light from the backlight (30, 45-48). The backlight has a light-output surface (45) with a first set of regions in the form of parallel evenly spaced strips (48). In a multiple-view mode of the display, these strips (48) emit light whereas the remainder of the output surface (45) is dark. In a single-view mode of operation of the display, the whole of the output surface (45) emits light substantially evenly across the display area of the modulator (1).
摘要:
A light-emitting device includes a substrate, a light-emissive layer disposed over the substrate, and a grating for aligning the light-emissive layer. The grating aligns molecules of the emissive layer, so that the device emits polarised. The grating also reduces wave guiding effects in the device, so increasing the useful light output of the device. The light-emitting device may be an organic light-emitting device (OLED). The grating may align substantially the entire area of the light-emissive layer in a first direction. In this case, substantially the entire emissive area of the device will emit layer of a single polarisation. Alternatively, the grating may align a first region of the light-emissive layer in a first direction and may align a second region of the light-emissive layer in a second direction different from the first direction.
摘要:
A multiple view display comprises a display device which displays first and second images in a spatially multiplexed fashion across the display surface. The device cooperates with a parallax optic such as a lenticular screen so as to act as a directional display sub-system directing light from the first and second images in different viewing directions. An optical system, for example comprising a lenticular screen of diverging elements, changes the angular separation of the viewing angle directions, for example so as to increase the angular separation.
摘要:
A display is provided having first and second direct view modes of operation. The display comprises a liquid crystal display panel and a backlight which is illuminated during the first mode so that the displayed image is visible throughout an extended viewing region in front of the device. The display also comprises a holographic element and a front light source, which is switched on for the second direct view mode. The holographic element redirects light from the front light source into part of the extended viewing region so that an image displayed by the device is visible in only a restricted portion of the viewing region.