Lc-tec Displays Ab

Ht, Inc.

Jesper Osterman

Terry J Scheffer

Fredrik Kihlborg

Se Jin Kang

A system included in an augmented reality (AR) headset prevents reduction in legibility of a near-eye image display for observation in combination with an observer's visual exterior view. The system includes a near-eye image source from which emanates near-eye image-carrying light and which is positioned out of the observer's direct visual exterior view. A dimming matrix display including multiple pixels is positioned so that the observer can see though them a scene in an exterior view. A partly transparent optical element is positioned so that the observer can see the scene in the exterior view and reflect the near-eye image-carrying light to provide an image for observation by the observer. A dimming controller controls amounts of scene-carrying light propagating through the multiple pixels from the locations in the scene and thereby prevents wash-out of the near-eye image when outside illumination is very bright.

Augmented reality headset including viewing direction independent single-layer, pixelated light dimming filter

A high-contrast liquid crystal light control device provides angle independent variable transmission of incident light for uniform gray shades. The liquid crystal light control device comprises a combination of first and second liquid crystal devices arranged in optical series and positioned between optical polarizers. The director field of the second liquid crystal device is a mirror image of the director field of the first liquid crystal device, and the first and second liquid crystal devices are placed together so that the azimuthal directions of the surface-contacting directors are in parallel alignment at the adjoining or confronting surfaces of the substrates of the first and second liquid crystal devices. The liquid crystal light control device provides, therefore, less angular variation of intermediate transmittances compared with that provided by prior art liquid crystal light control devices.

High contrast liquid crystal light control device providing angle independent variable transmission of incident light for uniform gray shades

A system included in a wearable viewing device () prevents reduction in legibility of a near-eye image display for observation in combination with an observer's visual exterior view. The system includes a near-eye image source () from which emanates near-eye image-carrying light and which is positioned out of the observer's direct visual exterior view. A dimming matrix display () including multiple pixels is positioned so that the observer () can see though them a scene () in an exterior view. A partly transparent optical element () is positioned so that the observer can see the scene in the exterior view and reflect the near-eye image-carrying light to provide an image for observation by the observer. A dimming controller () controls amounts of scene-carrying light propagating through the multiple pixels from the locations in the scene and thereby prevents wash-out of the near-eye image when outside illumination is very bright.

Viewing direction independent single-layer, pixelated light dimming filter

A high-contrast electro-optic liquid crystal camera iris provides angle independent transmission for uniform gray shades. The liquid crystal iris comprises a combination of first and second liquid crystal devices arranged in optical series and positioned between optical polarizers. The director field of the second liquid crystal device is a mirror image of the director field of the first liquid crystal device, and the first and second liquid crystal devices are placed together so that the azimuthal directions of the surface-contacting directors are in parallel alignment at the adjoining or confronting surfaces of the substrates of the first and second liquid crystal devices. The liquid crystal iris provides, therefore, less angular variation of intermediate transmittances compared with that provided by prior art liquid crystal irises.

High contrast electro-optic liquid crystal camera iris including liquid crystal material mixed with a dye to improve achromatic performance

A high-contrast electro-optic liquid crystal camera iris () provides angle independent transmission for uniform gray shades. The liquid crystal iris comprises a combination of first and second liquid crystal devices () arranged in optical series and positioned between optical polarizers (). The director field () of the second liquid crystal device is a mirror image of the director field () of the first liquid crystal device, and the first and second liquid crystal devices are placed together so that the azimuthal directions () of the surface-contacting directors () are in parallel alignment at the adjoining or confronting surfaces of the substrates () of the first and second liquid crystal devices. The liquid crystal iris provides, therefore, less angular variation of intermediate transmittances compared with that provided by prior art liquid crystal irises.

High contrast electro-optic liquid crystal camera iris providing angle independent transmission for uniform gray shades

A variable transmission filter combines in optical series first and second guest-host liquid crystal devices arranged such that one of them is rotated 180&#xb0; about its normal axis with respect to the other one. The reverse arrangement of the liquid crystal directors of the first and second guest-host liquid crystal devices improves the viewing angle range of the variable transmission filter but, without compensation, introduces a diminution of contrast ratio. A polarization state-changing device positioned between the first and second guest-host liquid crystal devices changes the polarization states of light exiting the first guest-host_liquid crystal device such that transmittance of light in first and second orthogonal polarization states incident on the first guest-host liquid crystal device responds to electric fields applied to the first and second liquid crystal devices and thereby counteracts the diminution of contrast ratio while maintaining the improved viewing angle range.

Electro-optic guest-host liquid crystal variable transmission filter with wide viewing angle

An optical shutter () includes a wavelength selective polarizing filter () in optical association with a liquid crystal polarization modulator () to rapidly switch between optical states to alternately transmit visible radiation and near infrared radiation. The wavelength selective polarizing filter is constructed to impart a polarization state to incident radiation and transmit polarized radiation within at least the visible wavelength region of the electromagnetic spectrum. The liquid crystal polarization modulator is positioned to receive incident radiation for internal propagation through the liquid crystal polarization modulator and is responsive to a first value and a second value of an applied control signal () to switch the internally propagating radiation to, respectively, a first polarization state and a second polarization state. The switching between the first and second polarization states produces, in cooperation with the wavelength selective polarizing filter, optical shutter output radiation in different wavelength regions of the electromagnetic spectrum.

Rapid switching optical shutter alternately transmitting visible radiation and near infrared radiation

An optical shutter employed in an enhanced vision system includes a wavelength selective polarizing filter in optical association with a liquid crystal polarization modulator to rapidly switch between optical states to alternately transmit visible (VIS) radiation and near infrared (NIR) radiation. The wavelength selective polarizing filter imparts a polarization state to incident radiation and transmits polarized radiation within at least the visible wavelength region. The liquid crystal polarization modulator receives incident radiation for internal propagation through the modulator and responds to first and second values of an applied control signal to switch the internally propagating radiation to, respectively, first and second polarization states. The switching between first and second polarization states produces, in cooperation with the wavelength selective polarizing filter, optical shutter output VIS and NIR radiation. A computer processes the output VIS and NIR radiation to produce for display a composite image formed of visible and infrared elements.

Enhanced vision system implemented with optical shutter alternately transmitting visible radiation and near infrared radiation

A high-contrast electro-optic liquid crystal camera iris provides angle independent transmission for uniform gray shades. The liquid crystal iris comprises a combination of first and second liquid crystal devices arranged in optical series and positioned between optical polarizers. The director field of the second liquid crystal device is a mirror image of the director field of the first liquid crystal device, and the first and second liquid crystal devices are placed together so that the azimuthal directions of the surface-contacting directors are in parallel alignment at the adjoining or confronting surfaces of the substrates of the first and second liquid crystal devices. The liquid crystal iris provides, therefore, less angular variation of intermediate transmittances compared with that provided by prior art liquid crystal iris.

Electro-optic liquid crystal camera iris providing angle independent transmission for uniform gray shades

An optical polarization state modulator assembly for use in a stereoscopic three-dimensional image projection system includes a spatial light modulator, a light source emitting multiple wavelength components of light for incidence on the spatial light modulator, and a projection lens. A polarization converter system cooperates with the spatial light modulator to produce in alternating sequence polarized light carrying first and second perspective view images of a scene in different ones of first and second subframes. A polarization modulator, in response to first and second drive signals, imparts to, respectively, the image-carrying polarized light a first output polarization state during the first subframe and to the image-carrying polarized light a second output polarization state during the second subframe. The image-carrying polarized light in the first and second output polarization states propagates through the projection lens for transmission to an observer.

Optical polarization state modulator assembly for use in stereoscopic three-dimensional image projection system

A near-infrared (NIR) optical shutter comprises a multiple-bandpass filter that is characterized by a bandstop filter region located between first and second bandpass filter regions. The first bandpass filter region passes visible light; the bandstop filter region blocks NIR light of wavelengths within a NIR light sensor band region; and the second bandpass filter region passes NIR light of longer wavelengths than a longer wavelength boundary of the NIR light sensor band region. A polarization state changer positioned between NIR polarizing filters and optically associated with the multiple-bandpass filter causes visible light transmission selectively in first and second light states. The polarization state changer in the first light state causes substantially reduced optical shutter transmission of NIR light in the second bandpass filter region and in the second light state causes substantially increased optical shutter transmission of NIR light in the second bandpass filter region.

Optical shutter for day-night filter operation

A polarization modulator for time-multiplexed stereoscopic 3D applications rapidly switches between two polarization states in alternate subframes. The polarization modulator uses two liquid crystal devices arranged in optical series and driven such that the second device compensates a change the first device makes to an input polarization state of incident light during alternate subframes. The compensating liquid crystal devices are characterized in that, if the same voltage is applied to both of them, the second device compensates the change that the first device makes to the input polarization state, regardless of the applied voltage level. If the applied voltage is changed from one level to another and the liquid crystal material in the liquid crystal devices relaxes to the new voltage level, polarization state compensation will take place throughout the duration of the relaxation so that the slow, unpowered transition does not manifest itself as a change in polarization state.

Growing community of inventors

Falun, Sweden

Jesper Osterman