Patents by Inventor Pasi Saarikko

Pasi Saarikko has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11231593
    Abstract: A Pancharatnam Berry Phase (PBP) color corrected structure is presented that comprises a plurality of switchable gratings and a plurality of PBP active elements. Each switchable grating has an inactive mode when reflects light of a specific color channel, of a set of color channels, and transmits light of other color channels in the set of color channels, wherein the specific color channel is different for each of the plurality of switchable gratings, and to have an active mode to transmit light that is inclusive of the set of color channels. The PBP active elements receive light output from at least one of the plurality of switchable gratings. Each of the PBP active elements is configured to adjust light of a different color channel of the set of color channels by a same amount to output light corrected for chromatic aberration for the set of color channels.
    Type: Grant
    Filed: January 21, 2021
    Date of Patent: January 25, 2022
    Assignee: Facebook Technologies, LLC
    Inventors: Lu Lu, Scott Charles McEldowney, Nada O'Brien, Pasi Saarikko
  • Patent number: 11221490
    Abstract: A multilayer grating is a diffraction grating that includes a plurality of layers. The plurality of layers arranged to form a 2-dimensional grating, the layers including at least a first patterned layer and a second patterned layer. The first patterned layer includes a plurality of different materials that are arranged in a first pattern such that the first patterned layer has a first index profile. The second patterned layer includes a plurality of different materials that are arranged in a second pattern such that the second patterned layer has a second index profile that is inverted relative to the first index profile. Ambient light incident on the first patterned layer and the second patterned layer creates a first diffracted ray and a second diffracted ray, respectively, and the first diffracted ray and the second diffracted ray destructively interfere with each other based in part on the inverted index profile.
    Type: Grant
    Filed: January 5, 2021
    Date of Patent: January 11, 2022
    Assignee: Facebook Technologies, LLC
    Inventors: Erik Shipton, Giuseppe Calafiore, Pasi Saarikko
  • Patent number: 11187904
    Abstract: In a waveguide display, a first projector is configured to generate display light for a first field of view (FOV) of a display image. A first input coupler is configured to couple the display light for the first FOV into a visibly transparent substrate. A first set of gratings is configured to couple the display light for the first FOV out of the substrate at a first two-dimensional array of locations of the substrate. A second projector is configured to generate display light for a second FOV of the display image different from the first FOV. A second input coupler is configured to couple the display light for the second FOV into the substrate. A second set of gratings is configured to couple the display light for the second FOV out of the substrate at a second two-dimensional array of locations of the substrate.
    Type: Grant
    Filed: March 6, 2020
    Date of Patent: November 30, 2021
    Assignee: FACEBOOK TECHNOLOGIES, LLC
    Inventors: Wanli Chi, Dominic Meiser, Yang Yang, Wai Sze Tiffany Lam, Pasi Saarikko
  • Patent number: 11175511
    Abstract: A waveguide display includes a substrate transparent to visible light and a projector configured to generate display light for an image, where the display light includes display light for a first field of view (FOV) of the image and display light for a second FOV of the image. The waveguide display also includes a first input coupler configured to couple the display light for the first FOV into the substrate, a first set of gratings configured to couple the display light for the first FOV out of the substrate at a first two-dimensional array of locations of the substrate, a second input coupler configured to couple the display light for the second FOV into the substrate, and a second set of gratings configured to couple the display light for the second FOV out of the substrate at a second two-dimensional array of locations of the substrate.
    Type: Grant
    Filed: April 3, 2020
    Date of Patent: November 16, 2021
    Assignee: FACEBOOK TECHNOLOGIES, LLC
    Inventors: Wanli Chi, Dominic Meiser, Yang Yang, Wai Sze Tiffany Lam, Pasi Saarikko
  • Patent number: 11169379
    Abstract: A waveguide display includes a waveguide transparent to visible light, a first volume Bragg grating (VBG) on the waveguide and characterized by a first refractive index modulation, and a second reflection VBG on the waveguide and including a plurality of regions characterized by different respective refractive index modulations. The first reflection VBG is configured to diffract display light in a first wavelength range and a first field of view (FOV) range such that the display light in the first wavelength range and the first FOV range propagates in the waveguide through total internal reflection to the plurality of regions of the second reflection VBG. The plurality of regions of the second reflection VBG are configured to diffract the display light in different respective wavelength ranges within the first wavelength range and the first FOV range.
    Type: Grant
    Filed: April 3, 2020
    Date of Patent: November 9, 2021
    Assignee: FACEBOOK TECHNOLOGIES, LLC
    Inventors: Wanli Chi, Dominic Meiser, Yang Yang, Wai Sze Tiffany Lam, Pasi Saarikko, Ningfeng Huang
  • Publication number: 20210341654
    Abstract: A pupil replication waveguide for a projector display includes a slab of transparent material for propagating display light in the slab via total internal reflection. A diffraction grating is supported by the slab. The diffraction grating includes a plurality of tapered slanted fringes in a substrate for out-coupling the display light from the slab by diffraction into a blazed diffraction order. A greater portion of the display light is out-coupled into the blazed diffraction order, and a smaller portion of the display light is out-coupled into a non-blazed diffraction order. The tapered fringes result in the duty cycle of the diffraction grating varying along the thickness direction of the diffraction grating, to facilitate suppressing the portion of the display light out-coupled into the non-blazed diffraction order.
    Type: Application
    Filed: July 16, 2021
    Publication date: November 4, 2021
    Inventors: Hee Yoon Lee, Ningfeng Huang, Pasi Saarikko, Yu Shi, Giuseppe Calafiore, Nihar Ranjan Mohanty
  • Patent number: 11143866
    Abstract: A waveguide is provided for conveying image light. The waveguide includes an input port for receiving a first beam of image light carrying an image in a wavelength band. A first diffraction grating of the waveguide includes a plurality of volume Bragg gratings (VBGs) configured to expand the first beam along a first axis and to redirect the first beam towards a second diffraction grating of the waveguide. The second diffraction grating includes a plurality of VBGs configured to receive the first beam from the first diffraction grating and to out-couple different portions of the first wavelength band of the first beam along a second axis, thereby expanding the first beam along the second axis for observation of the image by a user.
    Type: Grant
    Filed: June 22, 2020
    Date of Patent: October 12, 2021
    Assignee: FACEBOOK TECHNOLOGIES, LLC
    Inventors: Wanli Chi, Hee Yoon Lee, Pasi Saarikko
  • Publication number: 20210278676
    Abstract: A waveguide display includes light sources, a source waveguide, an output waveguide, and a controller. Light from each of the light sources is coupled into the source waveguide. The source waveguide includes gratings with a constant period determined based on the conditions for total internal reflection and first order diffraction of the received image light. The emitted image light is coupled into the output waveguide at several entrance locations. The output waveguide outputs expanded image lights at a location offset from the entrance location, and the location/direction of the emitted expanded image light is based in part on the orientation of the light sources. Each of the expanded image light is associated with a field of view of the expanded image light emitted by the output waveguide.
    Type: Application
    Filed: May 25, 2021
    Publication date: September 9, 2021
    Inventor: Pasi Saarikko
  • Patent number: 11112607
    Abstract: The disclosed apparatus may include a waveguide configuration that may include (1) a coupling area having at least one coupling element configured to receive a plurality of monochromatic images, where each of the monochromatic images is of a predetermined wavelength of light, (2) a propagation area in which light, received via the at least one coupling element, moves within a length of the waveguide configuration, and (3) a decoupling area that extends along the propagation area and includes decoupling elements that project a polychromatic image toward an eyebox, where the polychromatic image includes the monochromatic images of the predetermined wavelengths of light. Associated systems and devices are also provided herein.
    Type: Grant
    Filed: October 11, 2018
    Date of Patent: September 7, 2021
    Assignee: Facebook Technologies, LLC
    Inventors: Nicholas Daniel Trail, Pasi Saarikko
  • Patent number: 11114002
    Abstract: A waveguide display includes a source assembly, an output waveguide, and a controller. The source assembly includes a light source and an optics system. The light source includes source elements arranged in a 1D or 2D array that emit image light. The optics system includes a scanning mirror assembly that scans the image light to particular locations based on scanning instructions. The output waveguide receives the scanned image light from the scanning mirror assembly and outputs an expanded image light. In some embodiments, the waveguide display includes a source waveguide and the 1D array of source elements. The source waveguide receives a conditioned image light from the source assembly. The controller generates the scanning instructions and provides the scanning instructions to the scanning mirror assembly. In some embodiments, the controller provides the scanning instructions to an actuator assembly of the source waveguide.
    Type: Grant
    Filed: July 22, 2020
    Date of Patent: September 7, 2021
    Assignee: Facebook Technologies, LLC
    Inventors: Wanli Chi, Pasi Saarikko, Hee Yoon Lee
  • Patent number: 11099309
    Abstract: A pupil replication waveguide for a projector display includes a slab of transparent material for propagating display light in the slab via total internal reflection. A diffraction grating is supported by the slab. The diffraction grating includes a plurality of tapered slanted fringes in a substrate for out-coupling the display light from the slab by diffraction into a blazed diffraction order. A greater portion of the display light is out-coupled into the blazed diffraction order, and a smaller portion of the display light is out-coupled into a non-blazed diffraction order. The tapered fringes result in the duty cycle of the diffraction grating varying along the thickness direction of the diffraction grating, to facilitate suppressing the portion of the display light out-coupled into the non-blazed diffraction order.
    Type: Grant
    Filed: August 23, 2019
    Date of Patent: August 24, 2021
    Assignee: FACEBOOK TECHNOLOGIES, LLC
    Inventors: Hee Yoon Lee, Ningfeng Huang, Pasi Saarikko, Yu Shi, Giuseppe Calafiore, Nihar Ranjan Mohanty
  • Patent number: 11067811
    Abstract: A waveguide display includes a substrate transparent to visible light, a coupler configured to couple display light into the substrate such that the display light propagates within the substrate through total internal reflection, a first multiplexed volume Bragg grating (VBG) on the substrate, and a second multiplexed VBG on the substrate. The second multiplexed VBG overlaps with the first multiplexed VBG in at least a see-through region of the waveguide display. The first multiplexed VBG is configured to diffract the display light to two or more regions of the second multiplexed VBG, and the second multiplexed VBG is configured to diffract the display light to two or more regions of an eyebox of the waveguide display.
    Type: Grant
    Filed: December 24, 2019
    Date of Patent: July 20, 2021
    Assignee: FACEBOOK TECHNOLOGIES, LLC
    Inventors: Wanli Chi, Hee Yoon Lee, Pasi Saarikko
  • Publication number: 20210199873
    Abstract: A waveguide display includes a first substrate having two opposing sides, a grating on a first side of the two opposing sides of the first substrate and configured to couple display light into or out of the first substrate, a first antireflection layer on a first surface of the grating and configured to reduce reflection of visible light at the first surface of the grating, and a second antireflection layer on a second side of the two opposing sides of the first substrate and configured to reduce reflection of the visible light at the second side of the first substrate.
    Type: Application
    Filed: December 26, 2019
    Publication date: July 1, 2021
    Inventors: Yu SHI, Hee Yoon LEE, Ningfeng HUANG, Giuseppe CALAFIORE, Pasi SAARIKKO
  • Patent number: 11048090
    Abstract: A waveguide display includes light sources, a source waveguide, an output waveguide, and a controller. Light from each of the light sources is coupled into the source waveguide. The source waveguide includes gratings with a constant period determined based on the conditions for total internal reflection and first order diffraction of the received image light. The emitted image light is coupled into the output waveguide at several entrance locations. The output waveguide outputs expanded image lights at a location offset from the entrance location, and the location/direction of the emitted expanded image light is based in part on the orientation of the light sources. Each of the expanded image light is associated with a field of view of the expanded image light emitted by the output waveguide.
    Type: Grant
    Filed: August 22, 2019
    Date of Patent: June 29, 2021
    Assignee: Facebook Technologies, LLC
    Inventor: Pasi Saarikko
  • Publication number: 20210173234
    Abstract: A diffraction grating includes a substrate and a plurality of fringes supported by the substrate. The fringes run parallel to each other in a first direction. A refractive index of a material of the plurality of fringes is anisotropic, whereby a refractive index contrast of the diffraction grating depends on direction of electric field of an impinging light beam, and through that dependence is a function of an azimuthal angle of the impinging light beam. A dependence of the diffraction efficiency on the azimuthal angle is affected by the dependence of the refractive index contrast on the direction of electric field of an impinging light beam. A pupil-replicating waveguide may use such a diffraction grating as a coupler for in- our out-coupling image light.
    Type: Application
    Filed: December 5, 2019
    Publication date: June 10, 2021
    Inventors: Siddharth Buddhiraju, Yu Shi, Ningfeng Huang, Hee Yoon Lee, Pasi Saarikko
  • Publication number: 20210157145
    Abstract: A multilayer grating is a diffraction grating that includes a plurality of layers. The plurality of layers arranged to form a 2-dimensional grating, the layers including at least a first patterned layer and a second patterned layer. The first patterned layer includes a plurality of different materials that are arranged in a first pattern such that the first patterned layer has a first index profile. The second patterned layer includes a plurality of different materials that are arranged in a second pattern such that the second patterned layer has a second index profile that is inverted relative to the first index profile. Ambient light incident on the first patterned layer and the second patterned layer creates a first diffracted ray and a second diffracted ray, respectively, and the first diffracted ray and the second diffracted ray destructively interfere with each other based in part on the inverted index profile.
    Type: Application
    Filed: January 5, 2021
    Publication date: May 27, 2021
    Inventors: Erik Shipton, Giuseppe Calafiore, Pasi Saarikko
  • Patent number: 11009765
    Abstract: A varifocal block includes, in optical series, a switchable half waveplate (SHWP) and a plurality of liquid crystal (LC) lenses. The SHWP outputs circularly polarized light, and a handedness of the circularly polarized light is controlled by the SHWP being in an active state or a non-active state. Each LC lens of the plurality of LC lenses has a plurality of optical states, the plurality of optical states including an additive state that adds optical power to the LC lens and a subtractive state that removes optical power from the LC lens. The plurality of optical states of each of the plurality of the LC lenses compounded in optical series provides a range of adjustment of optical power for the varifocal block.
    Type: Grant
    Filed: June 25, 2019
    Date of Patent: May 18, 2021
    Assignee: Facebook Technologies, LLC
    Inventors: Lu Lu, Scott Charles McEldowney, Pasi Saarikko
  • Publication number: 20210141130
    Abstract: A waveguide display includes an image light source for emitting polychromatic image light, and a waveguide of high-index material for transmitting polychromatic image light to an eyebox. The waveguide has an input grating and an offset output grating. The output grating is configured so that ambient light diffracted by the output grating is directed away from the eyebox or out of at least a central portion of the field of view so as to lessen the appearance of visual artifacts.
    Type: Application
    Filed: November 12, 2019
    Publication date: May 13, 2021
    Inventors: Hee Yoon Lee, Pasi Saarikko
  • Patent number: 10948723
    Abstract: A scanning display includes a light source and a scanning assembly. The light source is configured to emit source light from a plurality of rows of emitters that are arranged parallel to a first dimension. The scanning assembly includes at least one optical element that conditions the source light. The scanning assembly is configured to scan the conditioned source light along a second dimension that is orthogonal to the first dimension. The scanning assembly configured to output the scanned light over a portion of a target area of an output waveguide. And a brightness of the scanned image light offsets dimming caused by the output waveguide expanding the scanned light in at least one dimension.
    Type: Grant
    Filed: December 15, 2017
    Date of Patent: March 16, 2021
    Assignee: Facebook Technologies, LLC
    Inventors: Wanli Chi, Yijing Fu, Pasi Saarikko
  • Patent number: 10942378
    Abstract: A pupil-replicating waveguide suitable for operation with a coherent light source is disclosed. A waveguide body has opposed surfaces for guiding a beam of image light. An out-coupling element is disposed in an optical path of the beam for out-coupling portions of the beam at a plurality of spaced apart locations along the optical path. Electrodes are coupled to at least a portion of the waveguide body for modulating an optical path length of the optical path of the beam to create time-varying phase delays between the portions of the beam out-coupled by the out-coupling element.
    Type: Grant
    Filed: June 2, 2020
    Date of Patent: March 9, 2021
    Assignee: FACEBOOK TECHNOLOGIES, LLC
    Inventors: Andrew Maimone, Andrew Ouderkirk, Hee Yoon Lee, Ningfeng Huang, Maxwell Parsons, Scott Charles McEldowney, Babak Amirsolaimani, Pasi Saarikko, Wanli Chi, Giuseppe Calafiore, Alexander Koshelev, Barry David Silverstein, Lu Lu, Wai Sze Tiffany Lam, Gang Li, Stephan Lutgen, Francois Olivier, David Massoubre