PATENT DOCUMENT

Publication Number: US-10162203-B2
Application Number: US-201615336134-A
Country: US
Kind Code: B2

Title: Systems and methods for electronically controlling the viewing angle of a display

Abstract:
Systems and methods for electronically controlling the viewing angle of a display using liquid crystal optical elements are provided. Each liquid crystal optical element may be associated with a respective scattering module and may selectively steer a device generated light beam to one of two or more scattering regions of its associated scattering module. When a scattering region receives a steered light beam, the steered light beam may be scattered into a viewing cone having at least one viewing angle defined by a characteristic of that scatter region. Each liquid crystal optical element may be made from one or more suitable liquid crystal materials that can be controlled electronically to vary the effective index of refraction of one or more different regions of the liquid crystal optical element, thereby steering incoming light towards a particular one of two or more scattering regions of an associated scattering module.

Claims:
What is claimed is: 
     
       1. An electronic device comprising:
 a housing comprising an opening through a portion of the housing; 
 a light source that directs light towards the opening; and 
 a first display control subassembly comprising:
 a scattering module positioned between the light source and the opening, the scattering module comprising a plurality of scattering regions; and 
 a steering module positioned between the light source and the scattering module, the steering module comprising a liquid crystal material that is electronically controllable to direct a light beam from the light source towards a particular scattering region of the plurality of scattering regions, wherein the steering module applies a radial electric field gradient across the liquid crystal material based on a control signal from a control signal line. 
 
 
     
     
       2. The electronic device of  claim 1 , wherein the plurality of scattering regions comprises:
 a first scattering region that scatters light from the steering module towards the opening with a first viewing angle with respect to a first axis; and 
 a second scattering region that scatters light from the steering module towards the opening with a second viewing angle with respect to the first axis, wherein the second viewing angle is different than the first viewing angle. 
 
     
     
       3. The electronic device of  claim 1 , wherein:
 the scattering module and the steering module are positioned along a first axis; and 
 the plurality of scattering regions comprises at least a first scattering region and a second scattering region that are positioned along a second axis perpendicular to the first axis. 
 
     
     
       4. The electronic device of  claim 1 , wherein:
 the scattering module and the steering module are positioned along a first axis; 
 the plurality of scattering regions comprises a first scattering region and a second scattering region that are positioned in a plane perpendicular to the first axis; and 
 the second scattering region surrounds the first scattering region. 
 
     
     
       5. The electronic device of  claim 1 , wherein the liquid crystal material is electronically controllable to adjust a focal length of the steering module. 
     
     
       6. The electronic device of  claim 1  further comprising a light conditioning component positioned between the light source and the steering module. 
     
     
       7. The electronic device of  claim 1  further comprising a light conditioning component positioned between the steering module and the scattering module. 
     
     
       8. The electronic device of  claim 1  further comprising a light conditioning component positioned between the scattering module and the opening. 
     
     
       9. The electronic device of  claim 1 , wherein:
 at least one scattering region of the plurality of scattering regions scatters light towards the opening in a viewing cone comprising a first viewing angle with respect to a first axis and a second viewing angle with respect to a second axis; 
 the second viewing angle is different than the first viewing angle; and 
 the second axis is different than the first axis. 
 
     
     
       10. The electronic device of  claim 1  further comprising a second display control subassembly positioned adjacent the first display control subassembly. 
     
     
       11. The electronic device of  claim 10 , wherein the second display control subassembly comprises:
 a second scattering module positioned between the light source and the opening, the second scattering module comprising a second plurality of scattering regions; and 
 a second steering module positioned between the light source and the second scattering module, the second steering module comprising a second liquid crystal material that is electronically controllable to direct a second light beam from the light source towards a particular scattering region of the second plurality of scattering regions, wherein the second liquid crystal material of the second steering module of the second display control subassembly is electronically controllable by at least a second control signal provided by a second control signal line. 
 
     
     
       12. The electronic device of  claim 1 , wherein the plurality of scattering regions comprises:
 a first scattering region that scatters light from the steering module towards the opening in a first viewing cone; and 
 a second scattering region that scatters light from the steering module towards the opening in a second viewing cone that has a different size than the first viewing cone. 
 
     
     
       13. A control assembly positioned between a light source and a viewer to switch an image display between different viewing angles, the control assembly comprising:
 a scattering module positioned between the light source and the viewer, the scattering module comprising at least two scattering regions; and 
 a steering module positioned between the light source and the scattering module, the steering module comprising a liquid crystal material that is electronically controllable to direct a light beam from the light source towards a particular scattering region of the at least two scattering regions, wherein the steering module applies a radial electric field gradient across the liquid crystal material based on a control signal. 
 
     
     
       14. A method for controlling a viewing angle of a display comprising a first scattering region with first scattering properties and a second scattering region with second scattering properties, the method comprising:
 directing a light beam towards a liquid crystal material; 
 applying an electric field with a radial gradient across the liquid crystal material; and 
 steering the light beam from the liquid crystal material towards a particular scattering region of the first scattering region and the second scattering region. 
 
     
     
       15. The method of  claim 14 , wherein the steering comprises applying a variable electrical control signal to the liquid crystal material. 
     
     
       16. The method of  claim 14 , wherein the steering comprises no mechanical movement of the liquid crystal material. 
     
     
       17. The method of  claim 14  further comprising adjusting the brightness of the light beam based on the scattering properties of the particular scattering region, wherein the steering further comprises adjusting a focal length of the liquid crystal material using the applied control signal. 
     
     
       18. An electronic device comprising:
 a housing comprising an opening through a portion of the housing; 
 a light source that directs light towards the opening; and 
 a first display control subassembly comprising:
 a scattering module positioned between the light source and the opening, the scattering module comprising a plurality of scattering regions; and 
 a steering module positioned between the light source and the scattering module, the steering module comprising a liquid crystal material that is electronically controllable to direct a light beam from the light source towards a particular scattering region of the plurality of scattering regions, wherein:
 the scattering module and the steering module are positioned along a first axis; and 
 the plurality of scattering regions comprises first and second concentric scattering regions that are positioned in a plane perpendicular to the first axis. 
 
 
 
     
     
       19. The electronic device of  claim 18 , wherein the steering module applies a radial electric field gradient across the liquid crystal material based on a control signal.

Description:
This application is a continuation of U.S. patent application Ser. No. 12/622,268 filed Nov. 19, 2009, which is incorporated by reference in its entirety for all purposes. 
    
    
     FIELD OF THE INVENTION 
     This can relate to systems and methods for controlling the viewing angle of a display and, more particularly, to systems and methods for electronically controlling the viewing angle of a display using liquid crystal optical elements. 
     BACKGROUND OF THE DISCLOSURE 
     Many electronic devices include the ability to present visible information to a user. In particular, many cellular telephones, laptop computers, and other portable electronic devices include a display screen for projecting light beams representative of device generated information to one or more viewers. Often, a user of the device may choose to share this displayed information with others looking at the device from various angles with respect to the screen, while, in other situations, the user may only want a person positioned directly in front of the screen to be able to see the displayed information. However, due to processing limitations, display limitations, size limitations, and other limitations of such electronic devices, a user must generally shield the display screen away from unintended viewers or aim the display screen towards only an intended viewer. 
     SUMMARY OF THE DISCLOSURE 
     Systems and methods for electronically controlling the viewing angle of a display screen are provided. 
     For example, in some embodiments, there is provided an electronic device that may include a housing having an opening through a portion of the housing, a light source that directs light towards the opening, and a first display control subassembly. The first display control subassembly may include a scattering module positioned between the light source and the opening. The scattering module may include a plurality of scattering regions. The first display control subassembly may also include a steering module positioned between the light source and the scattering module. The steering module may include a liquid crystal material that is electronically controllable to direct a light beam from the light source towards a particular scattering region of the plurality of scattering regions. 
     The plurality of scattering regions may include a first scattering region that scatters light from the steering module towards the opening with a first viewing angle with respect to a first axis, and a second scattering region that scatters light from the steering module towards the opening with a second viewing angle with respect to the first axis. The second viewing angle may be different than the first viewing angle. In some embodiments, the steering module may include a linear electric field gradient across the liquid crystal material. In other embodiments, the steering module may include a radial electric field gradient across the liquid crystal material. The liquid crystal material may be electronically controllable to adjust an effective index of refraction of the steering module or to adjust a focal length of the steering module 
     In other embodiments, there is provided a method for controlling a viewing angle of a display having a first scattering region with first scattering properties and a second scattering region with second scattering properties. The method may include directing a light beam towards a liquid crystal material and steering the light beam from the liquid crystal material towards a particular scattering region of the first scattering region and the second scattering region. The steering may include applying a variable electrical control signal to the liquid crystal material. For example, the steering may also include adjusting an effective index of refraction of the liquid crystal material using the applied control signal or adjusting a focal length of the liquid crystal material using the applied control signal. In some embodiments, the method may also include adjusting the brightness of the light beam based on the scattering properties of the particular scattering region. Moreover, in some embodiments, the steering may not include any mechanical movement of the liquid crystal material. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects of the invention, its nature, and various features will become more apparent upon consideration of the following detailed description, taken in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout, and in which: 
         FIG. 1  is a schematic view of an illustrative electronic device in accordance with some embodiments of the invention; 
         FIG. 2A  is an isometric view of an illustrative electronic device with a display assembly in accordance with some embodiments of the invention; 
         FIG. 2B  is a horizontal cross-sectional view of a portion of the electronic device and display assembly of  FIG. 2A , taken from line IIB-IIB of  FIG. 2A , in accordance with some embodiments of the invention; 
         FIG. 2C  is a top view of the electronic device and display assembly of  FIGS. 2A and 2B , taken from line IIC-IIC of  FIG. 2B , in accordance with some embodiments of the invention; 
         FIG. 2D  is a top view of the electronic device and display assembly of  FIGS. 2A and 2B , taken from line IID-IID of  FIG. 2B , in accordance with some other embodiments of the invention; 
         FIG. 3  is an isometric view of a display subassembly in accordance with some embodiments of the invention; 
         FIG. 3A  is a side view of a portion of the display subassembly of  FIG. 3 , taken from line IIIA-IIIA of  FIG. 3 , in accordance with some embodiments of the invention; 
         FIG. 3B  is a side view of a portion of the display subassembly of  FIGS. 3 and 3A , taken from line IIIB-IIIB of  FIG. 3 , in accordance with some embodiments of the invention; 
         FIG. 4  is a side view of a display subassembly in accordance with some other embodiments of the invention; 
         FIG. 5  is a side view of a display subassembly in accordance with yet some other embodiments of the invention; 
         FIG. 5A  is a top view of the display subassembly of  FIG. 5 , taken from line VA-VA of  FIG. 5 , in accordance with some embodiments of the invention; and 
         FIG. 6  is a flowchart of an illustrative process for controlling a viewing angle of a display in accordance with some embodiments of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE DISCLOSURE 
     Systems and methods for electronically controlling the viewing angle of a display screen are provided and described with reference to  FIGS. 1-6 . 
     An electronic device may be operative to provide visible information to a user. For example, an electronic device may include a display assembly operative to present the visible information at various viewing angles. The display may be provided with one or more steering modules, each of which may be associated with a respective scattering module having two or more scattering regions. Each steering module may selectively steer a device generated light beam to one of the scattering regions of its associated scattering module. When a scattering region receives a steered light beam, the steered light beam may be scattered into a viewing cone having at least one viewing angle that may be at least partially defined by a characteristic of that scattering region. Therefore, the particular scattering region of a scattering module towards which a steering module steers a device generated light beam may determine a viewing angle of light provided by the display to the user. 
     In some embodiments, each steering module may include one or more liquid crystal optical elements, which may be made from one or more suitable liquid crystal materials. The optical properties of the liquid crystal materials can be controlled electronically. This electronic control may allow the effective index of refraction of one or more different regions of the liquid crystal optical elements to be varied, thereby steering incoming light towards a particular one of two or more scattering regions of an associated scattering module. 
       FIG. 1  is a schematic view of an illustrative electronic device  100  for displaying visible information to a user. Electronic device  100  may be any portable, mobile, or hand-held electronic device configured to present visible information on a display assembly wherever the user travels. Alternatively, electronic device  100  may not be portable at all, but may instead be generally stationary. Electronic device  100  can include, but is not limited to, a music player, video player, still image player, game player, other media player, music recorder, movie or video camera or recorder, still camera, other media recorder, radio, medical equipment, domestic appliance, transportation vehicle instrument, musical instrument, calculator, cellular telephone, other wireless communication device, personal digital assistant, remote control, pager, computer (e.g., desktop, laptop, tablet, server, etc.), monitor, television, stereo equipment, set up box, set-top box, boom box, modem, router, keyboard, mouse, speaker, printer, and combinations thereof. In some embodiments, electronic device  100  may perform a single function (e.g., a device dedicated to displaying image content) and, in other embodiments, electronic device  100  may perform multiple functions (e.g., a device that displays image content, plays music, and receives and transmits telephone calls). 
     Electronic device  100  may include a processor or control circuitry  102 , memory  104 , communications circuitry  106 , power supply  108 , input component  110 , and display assembly  112 . Electronic device  100  may also include a bus  103  that may provide a data transfer path for transferring data and/or power, to, from, or between various other components of device  100 . In some embodiments, one or more components of electronic device  100  may be combined or omitted. Moreover, electronic device  100  may include other components not combined or included in  FIG. 1 . For example, electronic device  100  may include motion detection circuitry, light sensing circuitry, positioning circuitry, or several instances of the components shown in  FIG. 1 . For the sake of simplicity, only one of each of the components is shown in  FIG. 1 . 
     Memory  104  may include one or more storage mediums, including for example, a hard-drive, flash memory, permanent memory such as read-only memory (“ROM”), semi-permanent memory such as random access memory (“RAM”), any other suitable type of storage component, or any combination thereof. Memory  104  may include cache memory, which may be one or more different types of memory used for temporarily storing data for electronic device applications. Memory  104  may store media data (e.g., music, image, and video files), software (e.g., for implementing functions on device  100 ), firmware, preference information (e.g., media playback preferences), lifestyle information (e.g., food preferences), exercise information (e.g., information obtained by exercise monitoring equipment), transaction information (e.g., information such as credit card information), wireless connection information (e.g., information that may enable device  100  to establish a wireless connection), subscription information (e.g., information that keeps track of podcasts or television shows or other media a user subscribes to), contact information (e.g., telephone numbers and e-mail addresses), calendar information, any other suitable data, or any combination thereof. 
     Communications circuitry  106  may be provided to allow device  100  to communicate with one or more other electronic devices or servers using any suitable communications protocol. For example, communications circuitry  106  may support Wi-Fi™ (e.g., an 802.11 protocol), Ethernet, Bluetooth™, high frequency systems (e.g., 900 MHz, 2.4 GHz, and 5.6 GHz communication systems), infrared, transmission control protocol/internet protocol (“TCP/IP”) (e.g., any of the protocols used in each of the TCP/IP layers), hypertext transfer protocol (“HTTP”), BitTorrent′, file transfer protocol (“FTP”), real-time transport protocol (“RTP”), real-time streaming protocol (“RTSP”), secure shell protocol (“SSH”), any other communications protocol, or any combination thereof. Communications circuitry  106  may also include circuitry that can enable device  100  to be electrically coupled to another device (e.g., a computer or an accessory device) and communicate with that other device, either wirelessly or via a wired connection. 
     Power supply  108  may provide power to one or more of the components of device  100 . In some embodiments, power supply  108  can be coupled to a power grid (e.g., when device  100  is not a portable device, such as a desktop computer). In some embodiments, power supply  108  can include one or more batteries for providing power (e.g., when device  100  is a portable device, such as a cellular telephone). As another example, power supply  108  can be configured to generate power from a natural source (e.g., solar power using one or more solar cells). 
     One or more input components  110  may be provided to permit a user to interact or interface with device  100 . For example, input component  110  can take a variety of forms, including, but not limited to, a track pad, dial, click wheel, scroll wheel, touch screen, one or more buttons (e.g., a keyboard), mouse, joy stick, track ball, and combinations thereof. For example, input component  110  may include a multi-touch screen. Each input component  110  can be configured to provide one or more dedicated control functions for making selections or issuing commands associated with operating device  100 . 
     Electronic device  100  may also include one or more output components that may present information (e.g., textual, graphical, audible, and/or tactile information) to a user of device  100 . An output component of electronic device  100  may take various forms, including, but not limited, to audio speakers, headphones, audio line-outs, visual displays, antennas, infrared ports, rumblers, vibrators, or combinations thereof. 
     For example, electronic device  100  may include display assembly  112  as an output component. Display  112  may include any suitable type of display or interface for presenting visible information to a user of device  100 . In some embodiments, display  112  may include a display embedded in device  100  or coupled to device  100  (e.g., a removable display). Display  112  may include, for example, a liquid crystal display (“LCD”), a light emitting diode (“LED”) display, an organic light-emitting diode (“OLED”) display, a surface-conduction electron-emitter display (“SED”), a carbon nanotube display, a nanocrystal display, any other suitable type of display, or combination thereof. Alternatively, display  112  can include a movable display or a projecting system for providing a display of content on a surface remote from electronic device  100 , such as, for example, a video projector, a head-up display, or a three-dimensional (e.g., holographic) display. As another example, display  112  may include a digital or mechanical viewfinder. In some embodiments, display  112  may include a viewfinder of the type found in compact digital cameras, reflex cameras, or any other suitable still or video camera. 
     It should be noted that one or more input components and one or more output components may sometimes be referred to collectively as an I/O interface (e.g., input component  110  and display  112  as I/O interface  111 ). It should also be noted that input component  110  and display  112  may sometimes be a single I/O component, such as a touch screen that may receive input information through a user&#39;s touch of a display screen and that may also provide visual information to a user via that same display screen. 
     Processor  102  of device  100  may control the operation of many functions and other circuitry provided by device  100 . For example, processor  102  may receive input signals from input component  110  and/or drive output signals to display assembly  112 . 
     Processor  102  may load a user interface program (e.g., a program stored in memory  104  or another device or server) to determine how instructions or data received via an input component  110  may manipulate the way in which information is provided to the user via an output component (e.g., display  112 ). For example, processor  102  may control the viewing angle of the visible information presented to the user by display  112  or may otherwise instruct display  112  to alter the viewing angle. 
     Electronic device  100  may also be provided with a housing  101  that may at least partially enclose one or more of the components of device  100  for protecting them from debris and other degrading forces external to device  100 . In some embodiments, one or more of the components may be provided within its own housing (e.g., input component  110  may be an independent keyboard or mouse within its own housing that may wirelessly or through a wire communicate with processor  102 , which may be provided within its own housing). 
       FIGS. 2A-2D  show an illustrative electronic device  200 . Electronic device  200  may include some or all of the features of electronic device  100  of  FIG. 1 . In particular, as shown in  FIG. 2A , for example, electronic device  200  may include a display assembly  212  positioned at an opening  205  through a wall  207  of housing  201  of device  200 . In some embodiments, display  212  may be a touch screen and may also act as an input component for device  200 . Therefore, display  212  may provide an input region (e.g., input region  210 ′) on a portion of display  212  that may receive a user touch event for instructing device  200  (e.g., an instruction to alter the viewing angle or other characteristic of display  212 ). In other embodiments, electronic device  200  may include an additional input component (e.g., input component  210 ), which may be distinct from display  212 , and which may be used to receive user inputs for instructing device  200  (e.g., an instruction to alter the viewing angle or other characteristic of display  212 ). 
     The viewing angle of a display may be the maximum angle in the entire range of angles an observer may make between their line of sight and a particular point on the face of the display exposed to the observer within a particular plane while being able to see an acceptably bright image. Light beams projected from a point of the display may provide a viewing cone that may be defined by at least one specific viewing angle. 
       FIG. 2B  is a horizontal cross-sectional view of a portion of electronic device  200  according to some embodiments. As shown in  FIG. 2B , display assembly  212  may include an array of display subassemblies  220  (e.g., an array including display subassemblies  220   a - 220   k ). Each display subassembly  220  may include a respective image generating module  222 , a respective beam steering module  224 , and a respective beam scattering module  226 . As shown, each scattering module  226  may include two or more scattering regions (e.g., at least a first scattering region  228  and a second scattering region  230 ). 
     Image generating module  222  of each display subassembly  220  may direct a generated beam of light  223  towards a respective beam steering module  224  of that display subassembly  220 . Beam steering module  224  of each display subassembly  220  may receive the generated beam  223  from its respective image generating module  222  and may steer that beam  223  towards one of the scattering regions of the respective scattering module  226  of that display subassembly  220 . For example, as shown in  FIG. 2B , each beam steering module  224  may steer a received beam  223  towards either first scattering region  228  as a first steered beam  225  or towards second scattering region  230  as a second steered beam  227 . Each one of the beams that may be steered by a beam steering module  224  (e.g., steered beams  225  and  227 ) may be substantially identical to the generated beam  223  received at that steering module  224  from its respective image generating module  222 . 
     In some embodiments, each steering module  224  may include one or more liquid crystal optical elements, which may be made from one or more suitable liquid crystal materials. The optical properties of the one or more liquid crystal materials may be controlled electronically. For example, as shown in  FIG. 2B , at least one control signal line  250  may be coupled to each steering module  224  of display  212  for providing at least one variable voltage or other electrical signal, which may be controlled by a processor or other component of device  200 , to vary the optical properties of each steering module  224 . This electronic control may vary the effective index of refraction of one or more different regions of the one or more liquid crystal optical elements of each steering module  224 , thereby steering incoming light towards a scattering region of an associated scattering module  226 . For example, a liquid crystal optical element of steering module  224  may include one or more crystals that may be rotated within a fluid in response to the electrical signal applied to the steering module. Such rotation may affect the effective index of refraction of steering module  224  (e.g., the index of refraction with respect to the direction of an incoming light beam  223 ). 
     While only one control signal line  250  is shown in  FIG. 2B  as being coupled to all of the steering modules  224  of display  212  for controlling all steering modules  224  at the same time with the same control signal, for example, it is to be understood that, in other embodiments, each steering module  224  may be coupled to and independently controlled by its own control signal line  250  that may provide one or more control signals within one or more ranges of values. 
     Each liquid crystal optical element of each steering module  224  may function as an optical “wedge,” such that a linear gradient in the index of refraction of the element may provide a “beam steering” effect. In conventional geometric optics, the geometric shape of a “wedge” element may change the direction of a beam of light transiting through the wedge, such that the angle of the wedge with respect to the beam of light entering the wedge may control the angular change in direction of the beam as it exits the wedge. However, in some embodiments, a liquid crystal optical element may provide a “wedge angle” controllable by a variable control voltage applied to the liquid crystal optical element, such that light beams may be “steered” dynamically under electronic control, for example, without mechanical movement of the beam steering module itself. Thus, the “steering” effect achieved by the liquid crystal optical element may be an electronically controllable change in the direction of beam propagation. 
     Once a steered beam is received at one of the scattering regions of an associated scattering module  226 , the scattering region may scatter the steered beam into a viewing cone  235  that may be defined by at least one viewing angle  237 . Each viewing angle  237  that may at least partially define a viewing cone  235  may be dictated by one or more properties of the particular scattering region from which it was scattered. For example, one or more scattering regions of a scattering module  226  (e.g., first scattering region  228  and/or second scattering region  230 ) may include different scattering properties than each of the one or more other scattering regions of that scattering module  226 . In some embodiments, one or more scattering regions of a scattering module  226  may be an opal glass or any other suitable material having a particular type of diffusion powder or other suitable material therein for scattering incoming light into a viewing cone  235  with at least one particular viewing angle  237 . Alternatively or additionally, one or more scattering regions of a scattering module  226  may include a transparent material or any other suitable material having an engineered texture for providing a particular surface profile or roughness for scattering incoming light into a viewing cone  235  with at least one particular viewing angle  237 . In some embodiments, for example, one or more scattering regions of a scattering module  226  may be provided with a holographic optical material, such as holographic optical material made available by Physical Optics Corporation of Torrance, Calif., which may scatter incoming light into a viewing cone  235  defined by at least two different viewing angles  237  (e.g., a horizontal viewing angle and a vertical viewing angle). 
     As shown in  FIG. 2B , for example, when beam steering module  224   a  of display subassembly  220   a  steers generated beam  223   a  towards first scattering region  228   a  of scattering module  226   a  as a first steered beam  225   a , first scattering region  228   a  may scatter steered beam  225   a  as a scattered beam  229   a  away from display  212  (e.g., through opening  205 , towards a user  290  of device  200 ) into a viewing cone  235   a  having a viewing angle  237   a  of angle size α with respect to the X-axis. In some embodiments, each scattering module  226  of display assembly  212  may include a first scattering region  228  having similar scattering properties to each of the other first scattering regions  228  of display assembly  212 . For example, when beam steering module  224   d  of display subassembly  220   d  steers generated beam  223   d  towards first scattering region  228   d  of scattering module  226   d  as a first steered beam  225   d , first scattering region  228   d  may scatter steered beam  225   d  as a scattered beam  229   d  away from display  212  into a viewing cone  235   d  having a viewing angle  237   d  of the same angle size α as that of viewing angle  237   a  of viewing cone  235   a . Although not shown in  FIG. 2B , for the sake of clarity, the same may be true for each of the other subassemblies  220  (e.g., subassemblies  220   b ,  220   c , and  220   e - 220   k ), when its respective steering module  224  steers a steered beam  225  towards its first scattering region  228 . 
     However, each scattering module  226  may also include at least a second scattering region  230  having scattering properties different from that of its first scattering region  228 . For example, as also shown in  FIG. 2B , when beam steering module  224   h  of display subassembly  220   h  steers generated beam  223   h  towards second scattering region  230   h  of scattering module  226   h  as a second steered beam  227   h , second scattering region  230   h  may scatter steered beam  227   h  as a scattered beam  231   h  away from display  212  (e.g., towards a user  290  of device  200 ) into a viewing cone  235   h  having a viewing angle  237   h  of angle size β with respect to the X-axis. Angle size β may be any suitable viewing angle size that is larger or smaller than viewing angle size α. In some embodiments, each scattering module  226  of display assembly  212  may include a second scattering region  230  having similar scattering properties to each of the other second scattering regions  230  of display assembly  212 . For example, when beam steering module  224   k  of display subassembly  220   k  steers generated beam  223   k  towards second scattering region  230   k  of scattering module  226   k  as a second steered beam  227   k , second scattering region  230   k  may scatter steered beam  227   k  as a scattered beam  231   k  away from display  212  into a viewing cone  235   k  having a viewing angle  237   k  of the same angle size β as that of viewing cone  235   h . Although not shown in  FIG. 2B , for the sake of clarity, the same may be true for each of the other subassemblies  220  (e.g., subassemblies  220   a - 220   g ,  220   i , and  220   j ), when its respective steering module  224  steers a steered beam  227  towards its second scattering region  230 . 
     In some embodiments, the beam steering module  224  of every subassembly  220  may be operative to steer beams to its respective first scattering region  228  or to its respective second scattering region  230  at a particular moment, which may provide a consistent viewing angle across the array of subassemblies  220  (e.g., when one control signal line  250  is coupled to and controls all steering modules  226  of display assembly  212 ). In other embodiments, the beam steering module  224  of some subassemblies  220  may be operative to steer beams to its respective first scattering region  228  while the beam steering module  224  of other subassemblies  220  may be operative to steer beams to its respective second scattering region  230  at a particular moment, which may provide different viewing angles at different portions of the array of subassemblies  220  (e.g., when certain steering modules  226  of display assembly  212  are coupled to and controlled by a first control signal line  250  and when other steering modules  226  are coupled to and controlled by a second control signal line  250  that is independent from the first control signal line  250 ). 
     Display subassemblies  220  of display  212  may be positioned adjacent one another and may be arranged to form an array of one or more rows and one or more columns of subassemblies  220  under housing opening  205 . For example, as shown in the embodiments of  FIGS. 2C and 2D , subassemblies  220  may be arranged to form an array of ten rows and eleven columns under housing opening  205  (e.g., respectively along the X-axis and the Y-axis), although it is to be understood that any suitable number of rows and columns may be used depending on the size and resolution of the display, for example. The various scattering regions of scattering modules  226  of display  212  may be arranged in any suitable pattern in the array of subassemblies  220 . 
     In some embodiments, as shown in  FIG. 2C , for example, subassemblies  220  may be arranged such that similar scattering regions from each scattering module may align in a linear fashion. For example, first scattering regions  228  of two adjacent scattering modules  226  may be adjacent one another and may align within a row or column of the array of subassemblies  220 , and second scattering regions  230  of two adjacent scattering modules  226  may likewise be adjacent one another and may align within a row or column of the array of subassemblies  220 . In other embodiments, as shown in  FIG. 2D , for example, subassemblies  220  may be arranged such that similar scattering regions from each scattering module may alternate between rows and columns of the subassembly array in a checkerboard or other suitable pattern. For example, first scattering regions  228  of any two adjacent scattering modules  226  in the same row or column may be separated from one another by a second scattering region  230  of one of the adjacent scattering modules  226  of the array of subassemblies  220 . Alternatively, subassemblies  220  may be staggered or positioned in any other suitable arrangement under housing opening  205 . 
     While each scattering module  226  is shown in  FIGS. 2B-2D  as having only two scattering regions (i.e., first scattering region  228  and second scattering region  230 ), it is to be understood that in other embodiments each scattering module may include three or more scattering regions. For example, rather than including only two scattering regions positioned adjacent one another (e.g., first scattering region  228  and second scattering region  230  aligned adjacent one another along the X-axis, as shown in  FIGS. 2B-2D ), a scattering module  226  may include three or more scattering regions positioned adjacent one another along a particular axis. In such embodiments, an associated steering module  224  may be operative to steer an incoming beam (e.g., beam  223 ) towards any one of those three or more adjacent scattering regions in response to one or more electronic control signals provided by at least one control signal line  250 . For example, different ranges of control signal values may control a steering module  224  to steer an incoming beam to respective different scattering regions. 
     In other embodiments, rather than including two or more scattering regions positioned adjacent one another along a particular axis (e.g., first scattering region  228  and second scattering region  230  aligned adjacent one another along the X-axis, as shown in  FIGS. 2B-2D ), a scattering module may include three or more scattering regions positioned in a non-linear fashion. For example, as shown in  FIG. 3 , a display subassembly  320 , which may be substantially similar to display subassemblies  220  of  FIGS. 2B-2D , may include a scattering module  326  having three or more scattering regions arranged in a two-dimensional array. Scattering module  326  may include four scattering regions  328 ,  330 ,  332 , and  334 , for example. These scattering regions may be positioned with respect to each other in any suitable manner in a two-dimensional array. For example, as shown in  FIG. 3 , scattering regions  328 ,  330 ,  332 , and  334  may be positioned adjacent one another in a two column by two row array (e.g., in the X-Y plane). 
     In some embodiments, beam steering module  324  associated with scattering module  326  may include two or more beam steering cells that may together steer incoming generated beam  323  from image generating module  322  towards one of the four scattering regions of scattering module  326 . For example, as shown in  FIG. 3 , beam steering module  324  may include a first beam steering cell  336 , a second beam steering cell  317 , and a third beam steering cell  319 . Image generating module  322  may direct a generated beam of light  323  towards first beam steering cell  336  of beam steering module  324 . First beam steering cell  336  may receive generated beam  323  and may steer that beam  323  towards one of second beam steering cell  317  and third beam steering cell  319 , which may be positioned adjacent one another along a first axis. For example, as shown in  FIG. 3 , second beam steering cell  317  and third beam steering cell  319  may be positioned adjacent one another along the Y-axis, and first beam steering cell  336  may steer received beam  323  either towards second beam steering cell  317  as a first steered beam  325  or towards third beam steering cell  319  as a second steered beam  327 . Each one of the beams that may be steered by first beam steering cell  336  (e.g., steered beams  325  and  327 ) may be substantially identical to the generated beam  323  received at first beam steering cell  336  from image generating module  322 . 
     If second beam steering cell  317  receives first steered beam  325  from first beam steering cell  336 , second beam steering cell  317  may steer that beam  325  towards one of first scattering region  328  and second scattering region  330  of scattering module  326 , which may be positioned adjacent one another along a second axis. For example, as shown in  FIG. 3 , first scattering region  328  and second scattering region  330  may be positioned adjacent one another along the X-axis, and second beam steering cell  317  may steer received beam  325  either towards first scattering region  328  as a steered beam  325 ′ or towards second scattering region  330  as a steered beam  325 ″. Each one of the beams that may be steered by second beam steering cell  317  (e.g., steered beams  325 ′ and  325 ″) may be substantially identical to the steered beam  325  received at second beam steering cell  317  from first beam steering cell  336 . Likewise, if third beam steering cell  319  receives second steered beam  327  from first beam steering cell  336 , third beam steering cell  319  may steer that beam  327  towards one of third scattering region  332  and fourth scattering region  334  of scattering module  326 , which may be positioned adjacent one another along a second axis. For example, as shown in  FIG. 3 , third scattering region  332  and fourth scattering region  334  may also be positioned adjacent one another along the X-axis, and third beam steering cell  319  may steer received beam  327  either towards third scattering region  332  as a steered beam  327 ′ or towards fourth scattering region  334  as a steered beam  327 ″. Each one of the beams that may be steered by third beam steering cell  319  (e.g., steered beams  327 ′ and  327 ″) may be substantially identical to the steered beam  327  received at third beam steering cell  319  from first beam steering cell  336 . 
     While first beam steering cell  336  is shown in  FIG. 3  to be spaced along axis Z from second beam steering cell  317  and third beam steering cell  319  in order to more clearly illustrate certain features, it is to be understood that the beam steering cells of steering module  324  may be positioned proximate to one another in some embodiments (e.g., as shown by steering cells  413  and  415  of steering module  424  of  FIG. 4 ). 
     While only one control signal line  350 , which may be substantially similar to control signal line  250  of  FIG. 2B , is shown in  FIG. 3  as being coupled to steering module  324  of display subassembly  320 , the same control signal may be provided by control signal line  350  to each beam steering cell of steering module  324  or a different control signal may be provided by control signal line  350  to a respective one of the beam steering cells of steering module  324  for controlling the steering cells independently. 
     Once a steered beam is received at one of the scattering regions of scattering module  326 , the scattering region may scatter the steered beam into a viewing cone  335  that may be defined by at least one viewing angle  337 . Each viewing angle  337  that may at least partially define a viewing cone  335  may be dictated by one or more properties of the particular scattering region from which it was scattered. For example, one or more scattering regions of scattering module  326  (e.g., first scattering region  328 , second scattering region  330 , third scattering region  332 , and fourth scattering region  334 ) may include different scattering properties than each of the other scattering regions of scattering module  326 . As shown in  FIG. 3 , for example, first scattering region  328  may scatter steered beam  325 ′ into a viewing cone  335 - 1 , second scattering region  330  may scatter steered beam  325 ″ into a viewing cone  335 - 2 , third scattering region  332  may scatter steered beam  327 ′ into a viewing cone  335 - 3 , and fourth scattering region  334  may scatter steered beam  327 ″ into a viewing cone  335 - 4 , and each of these viewing cones  335  may be defined by at least one viewing angle that differs from a viewing angle that defines each one of the other viewing cones  335 . 
     In some embodiments, a viewing cone may be defined by two or more viewing angles. For example, as shown in  FIGS. 3A and 3B , respectively, viewing cone  335 - 2  of second scattering region  330  of scattering module  326  may be defined by at least a horizontal viewing angle  337   z  with respect to the X-axis having a viewing angle size δ as well as a vertical viewing angle  337   v  with respect to the Y-axis having a viewing angle size θ, which may be any suitable viewing angle size that is larger or smaller than viewing angle size δ. Therefore, in such embodiments where viewing angle size δ is larger than viewing angle size θ, as shown in  FIGS. 3-3B , viewing cone  335 - 2  may have a relatively wide horizontal viewing angle and a relatively narrow vertical viewing angle. 
     In some embodiments, each of the other viewing cones  335  of scattering module  326  may differ from one another such that scattering module  326  may provide a user with a suitable shaped viewing cone for any one of various applications. For example, in such embodiments where viewing angle size δ is larger than viewing angle size θ, viewing cone  335 - 1  may be defined by a relatively narrow horizontal viewing angle size θ and a relatively narrow vertical viewing angle size θ, viewing cone  335 - 2  may be defined by a relatively wide horizontal viewing angle size δ and a relatively narrow vertical viewing angle size θ (see, e.g.,  FIGS. 3A and 3B ), viewing cone  335 - 3  may be defined by a relatively narrow horizontal viewing angle size θ and a relatively wide vertical viewing angle size δ, and viewing cone  335 - 4  may be defined by a relatively wide horizontal viewing angle size δ and a relatively wide vertical viewing angle size δ. Therefore, an electronic device provided with a display subassembly  320  may selectively generate a viewing cone  335  having a variable horizontal viewing angle and a variable vertical viewing angle to accommodate practically any situation. 
     In other embodiments, rather than including a single beam steering cell operative to steer an incoming beam towards a particular one of two or more scattering regions positioned adjacent one another along a particular axis (see, e.g.,  FIG. 2B ), and rather than including two or more beam steering cells operative to steer an incoming beam to one of three or more scattering regions arranged in a two-dimensional array (see, e.g.,  FIG. 3 ), a scattering module receiving an unpolarized light beam may alternatively or additionally include beam steering cells that are operative to steer respective types of polarized light to one of two or more scattering regions of an associated scattering module. For example, as shown in  FIG. 4 , a display subassembly  420 , which may be substantially similar to display subassemblies  220  of  FIGS. 2B-2D  and/or subassembly  320  of  FIG. 3 , may include a beam generating module  422 , a beam steering module  424 , and a beam scattering module  426 . Beam generating module  422  may be operative to transmit a generated unpolarized light beam  423   u  towards beam steering module  424 . Beam steering module  424  may include a first beam steering cell  413  and a second beam steering cell  415 . These two beam steering cells may be positioned adjacent one another along the Z-axis of subassembly  420 , for example. These two beam steering cells may be identical, but may be physically rotationally offset from one another about the Z-axis in the X-Y plane, such that one of the beam steering cells may be operative to steer the portion of unpolarized light beam  423   u  having a first polarization and such that the other one of the beam steering cells may be operative to steer the portion of unpolarized light beam  423   u  having a second polarization. 
     For example, as shown in  FIG. 4 , beam steering module  424  may include first beam steering cell  413  that may be configured to steer the portion of unpolarized light beam  423   u  having a first polarization (e.g., a horizontal polarization) towards one of the two or more scattering regions of associated scattering module  426  and that may be configured to pass the portion of unpolarized light beam  423   u  having a second polarization (e.g., a vertical polarization) towards second beam steering cell  415 . In some embodiments, first beam steering cell  413  may be configured to steer a horizontal polarization light portion of unpolarized light beam  423   u  towards one of the two or more scattering regions of associated scattering module  426  (e.g., as first steered horizontal polarization beam  425   h  towards first scattering region  428  or as second steered horizontal polarization beam  427   h  towards second scattering region  430 ). First beam steering cell  413  may also be configured to pass a vertical polarization light portion of unpolarized light beam  423   u  towards second beam steering cell  415  (e.g., as vertical polarization beam  423   v ). Similarly, second beam steering cell  415  may be configured to steer vertical polarization beam  423   v  towards one of the two or more scattering regions of associated scattering module  426  (e.g., as first steered vertical polarization beam  425   v  towards first scattering region  428  or as second steered vertical polarization beam  427   v  towards second scattering region  430 ). Moreover, second beam steering cell  415  may be configured to pass the steered horizontal polarization beams  425   h  and  427   h  from first beam steering cell  413  towards scattering module  426 . 
     While first beam steering cell  413  is shown in  FIG. 4  to be positioned along axis Z proximate to second beam steering cell  415 , it is to be understood that the beam steering cells of steering module  424  may be spaced apart from one another in some embodiments (e.g., as shown by steering cells  317  and  336  of steering module  324  of  FIG. 3 ). 
     As shown in  FIG. 4 , second or vertical polarization beam steering cell  415  may be positioned adjacent first or horizontal polarization beam steering cell  413 , along the Z-axis, between horizontal polarization beam steering cell  413  and scattering module  426 . However, it is to be understood that, in other embodiments, second or vertical polarization beam steering cell  415  may instead be positioned adjacent horizontal polarization beam steering cell  413 , along the Z-axis, between horizontal polarization beam steering cell  413  and image generating module  422 , while horizontal polarization beam steering cell  413  may be positioned between vertical polarization beam steering cell  415  and scattering module  426 . Moreover, it is to be understood that, in some embodiments, steering module  424  of subassembly  420  of  FIG. 4  may not only be provided with first polarization beam steering cell  413  and second polarization beam steering cell  415 , but steering module  424  may also be provided with one or more additional steering cells, such as steering cells  317 ,  319 , and  326  of  FIG. 3  for steering light beams (e.g., before or after polarization) to a two-dimensional array of scattering regions, for example. 
     While only one control signal line  450 , which may be substantially similar to control signal line  250  of  FIG. 2B  and/or control signal line  350  of  FIG. 3 , is shown in  FIG. 4  as being coupled to steering module  424  of display subassembly  420 , the same control signal may be provided by control signal line  450  to each beam steering cell of steering module  424  or a different control signal may be provided by control signal line  450  to a respective one of the beam steering cells of steering module  424  for controlling the steering cells independently. 
     As mentioned, a beam steering module may include an electric field gradient or profile applied across one or more liquid crystal optical elements that may be under dynamic electronic control for steering incoming light towards one of two or more scattering regions of an associated scattering module. The electric field may vary across the beam steering module for steering an incoming light beam in various directions towards the scattering module. For example, the electric field gradient may be linear across the liquid crystal material of the beam steering module, such that incoming light may be steered to one of two or more scattering regions positioned adjacent one another along a particular axis (e.g., first scattering region  228  and second scattering region  230  of  FIGS. 2B-2D  along the X-axis, or third scattering region  332  and fourth scattering region  334  of  FIG. 3  along the X-axis). In such embodiments, the linear gradient in the electric field of the liquid crystal optical elements across the beam steering module may function as an optical “wedge,” such that an effective index of refraction of the steering module may be adjusted to provide a “beam steering” effect for a light beam towards one of two or more linearly aligned scattering regions of a scattering module. 
     Alternatively, the electric field gradient may extend radially away from an axis, across the liquid crystal material of the beam steering module, such that incoming light may be directed towards one of two or more concentric or otherwise radially spaced scattering regions of a scattering module. In such embodiments, the radial gradient in the electric field of the liquid crystal optical elements across the beam steering module may function as an optical “lens,” such that a focal length of the steering module may be adjusted to provide a “focusing” effect for a light beam towards at least one of two or more radially spaced scattering regions of a scattering module. 
     For example, as shown in  FIG. 5 , a display subassembly  520 , which may be substantially similar to display subassemblies  220  of  FIGS. 2B-2D , subassembly  320  of  FIG. 3 , and/or subassembly  420  of  FIG. 4 , may include a beam generating module  522 , a beam steering module  524 , and a beam scattering module  526 . Beam generating module  522  may be operative to transmit a generated light beam  523  towards beam steering module  524 . Beam steering module  524  may include an electric field gradient or profile applied across one or more liquid crystal optical elements that may vary along beam steering module  524  radially away from the Z-axis under dynamic electronic control for directing incoming light beam  523  towards at least one of two or more scattering regions of associated scattering module  526 . As shown in  FIGS. 5 and 5A , for example, beam scattering module  526  may include two or more concentric or otherwise radially adjacent scattering regions, such as an inner scattering region  528  and an outer scattering region  530  that may at least partially surround inner scattering region  528  (e.g., about axis Z). Based on one or more received electronic control signals provided by control signal line  550 , beam steering module  524  may steer or focus received beam  523  towards inner beam scattering region  528  as first steered beam  525  or towards outer beam scattering region  530  as one or more second steered beams  527 . However, in some embodiments, when beam steering module  524  steers or focuses received beam  523  towards outer beam scattering region  530 , some of received beam  523  may also be steered towards inner beam scattering region  528  as well. 
     Once a steered beam is received at one of the scattering regions of scattering module  526 , the scattering region may scatter the steered beam into a viewing cone  535  that may be defined by at least one viewing angle  537 . Each viewing angle  537  that may at least partially define a viewing cone  535  may be dictated by one or more properties of the particular scattering region from which it was scattered. For example, one or more scattering regions of scattering module  526  (e.g., inner scattering region  528  and outer scattering region  530 ) may include different scattering properties than each of the other scattering regions of scattering module  526 . As shown in  FIG. 5 , for example, inner scattering region  528  may scatter steered beam  525  into a viewing cone  535 - 1 , and outer scattering region  530  may scatter each steered beam  527  into a viewing cone  535 - 2 . For example, viewing cone  535 - 1  of inner scattering region  528  may be defined by at least a horizontal viewing angle  537   n  with respect to the X-axis having a viewing angle size λ, and at least one viewing cone  535 - 2  of outer scattering region  530  may be defined by at least a horizontal viewing angle  537   t  with respect to the X-axis having a viewing angle size ψ, which may be any suitable viewing angle size that is larger or smaller than viewing angle size λ. Therefore, in such embodiments where viewing angle size λ is smaller than viewing angle size ψ, as shown in  FIG. 5 , viewing cone  535 - 1  may have a relatively narrow horizontal viewing angle and viewing cone  535 - 2  may have a relatively wide horizontal viewing angle. 
     Whether an electric field gradient or profile varies linearly, radially, or in any other suitable manner across the liquid crystal optical elements of a beam steering module, the gradient may be continuous or may be provided in distinct regions. Similarly, whether a beam scattering module includes two or more linearly aligned scattering regions, three or more scattering regions positioned in a two-dimensional array, two or more concentric or otherwise radially adjacent scattering regions, or any other suitable arrangement of scattering regions, the scattering properties of two adjacent scattering regions may gradually blend with one another or they may abruptly change at the portion of the scattering module where the two scattering regions meet. 
     In some embodiments, a display assembly may include a first subset of display subassemblies that may each include a scattering module having only two scattering regions, while a second subset of the display subassemblies may each include a scattering module having three or more scattering regions. Therefore, such a display assembly may be able to provide viewing cones with different possible viewing angles at different portions of the array of subassemblies. While each viewing angle of each viewing cone illustrated in  FIGS. 2B-5  is shown to be symmetrical about an axis substantially perpendicular to the display screen (e.g., symmetrical about the Z-axis), it is to be understood that a scattering region may be operative to scatter light into a viewing cone with at least one viewing angle that is not symmetrical about an axis substantially perpendicular to the display screen. 
     Each display subassembly may be associated with a respective subpixel, a respective pixel, a respective triad of pixels, or any other respective image element of the display assembly. Moreover, the steering and scattering capabilities of each subassembly may be performed on a light beam at various stages of conditioning for presentation to a user. For example, with reference to a display subassembly  220  of  FIG. 2B , each image generating module  222  may include a light generating component (e.g., a backlight) and one or more light conditioning components (e.g., one or more optical filters that may be under electronic control, such as a polarization filter, one or more shutters, and/or one or more colored filters for creating an image from the generated light). In such embodiments, a generated light beam  223  provided by an image generating module  222  may be steered, scattered, and then presented to a user without any additional optical filtering or conditioning. 
     Alternatively, with continued reference to a display subassembly  220  of  FIG. 2B , each image generating module  222  may include a light generating component, and a separate light conditioning component  222 ′ may be positioned elsewhere in the subassembly  220  to provide optical filtering before presenting a light beam to a user. For example, as shown in  FIG. 2B , a separate light conditioning component  222 ′ may be positioned in a subassembly  220  adjacent the beam scattering module  226  and between the scattering module  226  and a user, such that a scattered beam may be optically filtered before being presented to the user. As another example, a separate light conditioning component  222 ″ may be positioned in a subassembly  220  (see, e.g., subassembly  220   b ) between the beam steering module  224  and the beam scattering module  226 , such that a steered beam may be optically filtered before being scattered. In some embodiments, a single light guide pipe or any other suitable light generating assembly may be provided as the light generating component for two or more of the display subassemblies. 
     In some embodiments, the brightness or peak white level of the generated light beam  223  provided by the beam generating module of a particular subassembly  220  may be varied based on the viewing angle of its associated scattered beam provided by the scattering region  226  of that subassembly  220 . For example, in order to conserve power, when a smaller viewing angle is used for a light beam of a particular subassembly  220  (e.g., viewing angle size α by controlling beam steering module  224  to steer generated light beam  223  to first beam scattering region  228 ), the brightness of generated light beam  223  for that subassembly may be reduced. However, when a larger viewing angle is used for a light beam of a particular subassembly  220  (e.g., viewing angle size β by controlling beam steering module  224  to steer generated light beam  223  to second beam scattering region  230 ), the brightness of generated light beam  223  for that subassembly may be increased. For example, balancing the brightness of a generated light beam  223  with the selected viewing angle for that beam may provide a constant perceived brightness of the beam by one or more observers while conserving the power of device  200 . 
     In some embodiments, as shown in  FIG. 2B , for example, display assembly  212  may also include a screen  240  that may be positioned between beam scattering modules  226 , or separate light conditioning component  222 ′, and the exterior of device  200  (e.g., user  290 ). For example, this screen  240  may provide additional protection to display assembly  212 . 
       FIG. 6  is a flowchart of an illustrative process  600  for controlling a viewing angle of a display. The display may include a first scattering region with first scattering properties and a second scattering region with second scattering properties. At step  602 , a light beam may be directed towards a liquid crystal material. For example, the light beam may be generated by an image generating component (e.g., image generating component  222 ) or otherwise directed towards a beam steering module including a liquid crystal material. Next, at step  604 , the light beam may be steered from the liquid crystal material towards a particular scattering region of the first scattering region and the second scattering region. 
     For example, the steering at step  604  may include applying a variable electrical control signal to the liquid crystal material. In some embodiments, an effective index of refraction of the liquid crystal material may be adjusted using the applied control signal. In other embodiments, a focal length of the liquid crystal material may be adjusted using the applied control signal. Process  600  may also include adjusting the brightness of the light beam based on the scattering properties of the particular scattering region. For example, by balancing the brightness of a generated light beam with the selected viewing angle for that beam, a constant perceived brightness by one or more observers of that beam may be provided while conserving power. The steering at step  604  may not include any mechanical movement of the liquid crystal material. 
     It is understood that the steps shown in process  600  of  FIG. 6  are merely illustrative and that existing steps may be modified or omitted and that additional steps may be added. 
     While there have been described systems and methods for electronically controlling the viewing angle of a display screen, it is to be understood that many changes may be made therein without departing from the spirit and scope of the invention. It is also to be understood that various directional and orientational terms, such as “top” and “bottom,” “horizontal” and “vertical,” and the like, are used herein only for convenience, and that no fixed or absolute directional or orientational limitations are intended by the use of these words. For example, the displays of the invention can have any desired orientation. If reoriented, different directional or orientational terms may need to be used in their description, but that will not alter their fundamental nature as within the scope and spirit of the invention. 
     Those skilled in the art will appreciate that the invention can be practiced by other than the described embodiments, which are presented for purposes of illustration rather than of limitation.

Metadata:
Filing Date: 20161027
Publication Date: 20181225
Grant Date: 20181225
Priority Date: 20091119
Inventors: GERE, DAVID S.
Assignee: APPLE INC
CPC Classifications: [{"code": "G02F1/1323", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02F1/133504", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F1/292", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F1/137", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F1/133504", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F1/1323", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02F1/137", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F1/292", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 43086465