Optical system with adjustable light engine

Abstract

An optical system with an adjustable light engine is disclosed. An electronic device, such as a head-mounted device, may include a support structure and a display system coupled to the support structure. The display system may include a light engine that emits light into a waveguide that in turn directs the light to an eye-adapted region. To reposition the light engine relative to the waveguide, a locator may be included in the display system. In particular, the locator may rotate and / or translate the light engine laterally relative to the waveguide. As an example, the locator may be a fastener, flexure, hinge, curved track, cam and screw, rack and pinion, or piezoelectric actuator that moves the light engine about a pivot point. A plurality of positioners may be used to move the light engine in a plurality of directions. The light engine may be moved manually or using a motor, such as in response to sensor measurements.

Description

[0001] This application claims the benefit of U.S. Patent Application No. 18 / 917,202, filed Oct. 16, 2024, and U.S. Provisional Patent Application No. 63 / 604,033, filed Nov. 29, 2023, the entireties of which are hereby incorporated by reference. BACKGROUND OF THE INVENTION

[0002] The present invention relates generally to optical systems and, more particularly, to optical systems for displays.

[0003] An electronic device may include a display that presents an image to a user's eye. For example, devices such as virtual reality and augmented reality headsets may include a display having optical elements that allow a user to view the display. SUMMARY OF THE INVENTION

[0004] An electronic device such as a head-mounted device may be a support structure and may have one or more near-eye displays that generate an image for a user. The head-mounted device may be a pair of virtual reality glasses or may be an augmented reality headset that allows an observer to view both computer-generated images and real-world objects in the observer's surrounding environment.

[0005] The display may include a light engine that emits light into a waveguide, which in turn guides the light to an exit pupil region. It may be desirable to move the light engine relative to the waveguide. For example, the light engine may be displaced relative to the waveguide, or it may be desirable to modify the light output from the waveguide.

[0006] To reposition the light engine relative to the waveguide, a locator may be included in the display system. In particular, the locator may rotate and / or laterally translate the light engine relative to the waveguide. As an example, the locator may be a fastener, flexure, hinge, curved track, cam and screw, rack and pinion, or piezoelectric actuator that moves the light engine about a pivot point.

[0007] If desired, multiple locators may be used to move the light engine in multiple directions. For example, a first fastener may be used to rotate the light engine about a pivot point, and a second fastener may be used to laterally translate the light engine closer to and farther from the waveguide. Alternatively, two flexures may be used to rotate the light engine in two different directions (e.g., about two different pivot points).

[0008] The light engine can be moved manually or using a motor. If desired, the light engine can be moved automatically in response to sensor measurements. For example, the sensor can measure the position of the light engine relative to the waveguide, and if the light engine has shifted, the light engine can be repositioned. Alternatively or additionally, the sensor can measure the output of the waveguide, and the light engine can be repositioned to adjust the output of the waveguide. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 is a diagram of an exemplary system with a display in accordance with some embodiments.

[0010] Figure 2 is a top view of an exemplary optical system for a display with a waveguide having an input coupler that receives light from a display module in accordance with some embodiments.

[0011] Figure 3 is a top view of an exemplary display module with a light engine that can be rotated and / or translated in multiple directions in accordance with some embodiments.

[0012] Figure 4 is a top view of an exemplary display module with a light engine that can be rotated and / or translated using fasteners in accordance with some embodiments.

[0013] Figure 5 is a top view of an exemplary display module with a light engine that can be rotated and / or translated using flexures in accordance with some embodiments.

[0014] Figure 6 is a top view of an exemplary display module with a light engine that can be rotated and / or translated using a hinge in accordance with some embodiments.

[0015] Figure 7 is a top view of an exemplary display module with a light engine that can be rotated and / or translated using a curved track in accordance with some embodiments.

[0016] Figure 8A is a top view of an exemplary display module with a light engine that can be rotated and / or translated using a cam and screw in accordance with some embodiments.

[0017] Figure 8B is a front view of an exemplary cam and screw that can rotate and / or translate a light engine in accordance with some embodiments.

[0018] Figure 9 is a top view of an exemplary display module with a light engine that can be rotated and / or translated using a rack and pinion in accordance with some embodiments.

[0019] Figure 10is a top view of an exemplary display module having an optical engine that can be rotated and / or translated using a piezoelectric actuator, according to some embodiments.

[0020] Figure 11 is a flowchart of an exemplary process that can be used to adjust the position of an optical engine, according to some embodiments.

[0021] Figure 12 is a top view of an exemplary display module having an optical engine that can be rotated and / or translated in a first direction using a first fastener and in a second direction using a second fastener, according to some embodiments.

[0022] Figure 13 is a top view of an exemplary display module having an optical engine that can be rotated and / or translated in two different directions using a first flexure and a second flexure, according to some embodiments. DETAILED DESCRIPTION

[0023] A system, such as a head-mounted device or other electronic device, may include one or more displays. The display may be a digital micromirror display or other display having one or more optical engines. The optical engine may emit light into an optical display element (such as a waveguide), and the light may be reflected within the waveguide until the light exits the waveguide for viewing by a user of the device.

[0024] Because the light emitted by the optical engine travels within the waveguide for viewing by the user, the angle and position of the optical engine relative to the waveguide can affect the final image seen by the user. In some cases, such as when the optical engine becomes misaligned with the waveguide or when it is desired to modify the output of the waveguide, it may be desirable to allow correction of this angle and / or position. In particular, the optical engine may be rotatably mounted within the device, thereby allowing adjustment of the angle of the optical engine relative to the waveguide. The adjustment may be made automatically or manually.

[0025] The optical engine may be rotatably mounted using a locking goniometer or other locator. As some exemplary examples, fasteners, flexures, hinges, curved tracks, cams and screws, lead screws having a curved guiding path, rack and pinion, springs, or other suitable locators may be used to rotate the optical engine about a pivot point. Regardless of the locator used, the rotation mechanism may be lockable, such as lockable using a lock nut, a plunger and a stopper, a reworkable adhesive, or other suitable locking mechanisms. In this way, the angle and / or lateral position of the optical engine can be adjusted relative to the waveguide, and the position of the optical engine can be locked into place using one or more locking mechanisms.

[0026] Figure 1An exemplary system is shown, which has a device with one or more near-eye display systems, and the device may include a rotatably mounted light engine. System 10 may be a head-mounted device having one or more displays, such as a near-eye display 14 mounted within a support structure (housing) 20. System 10 may thus be referred to herein as device 10 and / or head-mounted device 10. The support structure 20 may be shaped like a pair of glasses (e.g., a support frame), may form a housing having a helmet shape, or may have other configurations for assisting in mounting and securing components of the near-eye display 14 on or near the user's head. The near-eye display 14 may include one or more display modules, such as display module 14A (also referred to herein as light engine 14A), and one or more optical systems, such as optical system 14B. The display module 14A may be mounted in a support structure such as support structure 20. Each display module 14A may emit light 22 (sometimes referred to herein as image light 22), and use the associated optical system in the optical system 14B to redirect the light toward the user's eyes at the eye comfort zone 24.

[0027] The operation of system 10 may be controlled using control circuit 16. The control circuit 16 may include storage and processing circuitry for controlling the operation of system 10. The circuit 16 may include storage devices such as hard disk drive storage, non-volatile memory (e.g., electrically programmable read-only memory configured to form a solid state drive), volatile memory (e.g., static or dynamic random access memory), etc. The processing circuitry in the control circuit 16 may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processors, power management units, audio chips, graphics processing units, application specific integrated circuits, and other integrated circuits. Software code (instructions) may be stored on the memory in the circuit 16 and run on the processing circuitry in the circuit 16 to implement operations for system 10 (e.g., data acquisition operations, operations involving adjusting components using control signals, image rendering operations for generating image content to be displayed to the user, etc.).

[0028] System 10 may include input-output circuitry such as input-output device 12. Input-output device 12 may be used to allow system 10 to receive data from external devices (e.g., a tethered computer, a portable device such as a handheld device or a laptop computer, or other electrical devices), and to allow a user to provide user input to the head-mounted device 10. Input-output device 12 may also be used to collect information about the environment in which system 10 (e.g., head-mounted device 10) operates. The output component in device 12 may allow system 10 to provide output to the user and may be used to communicate with external electronic devices. Input-output device 12 may include sensors and other components 18 (e.g., an image sensor for acquiring an image of a real-world object that is digitally merged with a virtual object on a display in system 10, an accelerometer, a depth sensor, a light sensor, a haptic output device, a speaker, a battery, a wireless communication circuit for communicating between system 10 and external electronic devices, etc.). In one suitable arrangement sometimes described herein by way of example, components 18 (also referred to herein as sensors 18) may include a gaze tracking sensor that collects gaze image data from the user's eyes at the fovea region 24 to track the direction of the user's gaze in real time.

[0029] Display module 14A (sometimes referred to herein as display engine 14A, display module 14A, light engine 14A, or projector 14A) may include a reflective display (e.g., a display having a light source that generates illumination light that is reflected from a reflective display panel to generate image light, such as a liquid crystal on silicon (LCOS) display, a digital micromirror device (DMD) display, or other spatial light modulator), an emissive display (e.g., a micro light-emitting diode (uLED) display, an organic light-emitting diode (OLED) display, a laser-based display, etc.), or other types of displays. The light source in display module 14A may include uLEDs, OLEDs, LEDs, lasers, combinations of these devices, or any other desired light-emitting component.

[0030] Optical system 14B may form lenses that allow an observer (see, e.g., the eyes of an observer at fovea region 24) to view the images on display 14. There may be two optical systems 14B associated with the user's respective left and right eyes (e.g., for forming a left lens and a right lens). A single display 14 may generate images for both eyes, or a pair of displays 14 may be used to display images. In a configuration having multiple displays (e.g., a left-eye display and a right-eye display), the focal length and position of the lenses formed by components in optical system 14B may be selected such that any gap present between the displays will be invisible to the user (e.g., such that the images of the left display and the right display overlap or merge seamlessly).

[0031] If desired, the optical system 14B may include components (e.g., an optical combiner, etc.) to allow real-world image light from a real-world image or object 27 to be optically combined with a virtual (computer-generated) image such as the virtual image in image light 22. In this type of system (sometimes referred to as an augmented reality system), a user of the system 10 may view both real-world content and computer-generated content overlaid on the real-world content. A camera-based augmented reality system may also be used in the device 10 (e.g., in an arrangement where a camera captures a real-world image of the object 27 and digitally combines such content with virtual content at the optical system 14B).

[0032] If desired, the system 10 may include wireless circuitry and / or other circuitry to support communication with a computer or other external device (e.g., a computer that provides image content to the display 14). During operation, the control circuit 16 may provide image content to the display 14. The content may be received remotely (e.g., from a computer or other content source coupled to the system 10) and / or may be generated by the control circuit 16 (e.g., text, other computer-generated content, etc.). The content provided by the control circuit 16 to the display 14 may be viewed by an observer at the eyepiece region 24.

[0033] Figure 2 Is usable in Figure 1 of the system 10. As Figure 2 shown, the near-eye display 14 may include one or more light engines, such as light engine 14A, and an optical system, such as optical system 14B. The optical system 14B may include optical elements such as one or more waveguides 26. The waveguides 26 may include one or more stacked substrates (e.g., stacked planar layers, curved layers, pinhole mirror layers, and / or tilted cut layers, sometimes referred to herein as waveguide substrates) formed of an optically transparent material (such as plastic, polymer, glass, etc.).

[0034] If desired, waveguide 26 may also include one or more layers of holographic recording medium (sometimes referred to herein as "holographic medium", "grating medium", or "diffraction grating medium"), on which one or more diffraction gratings (e.g., holographic phase gratings, sometimes referred to herein as "holograms") are recorded. Holographic recording may be stored as an optical interference pattern (e.g., alternating regions of different refractive indices) within a photosensitive optical material such as the holographic medium. This optical interference pattern may produce a holographic phase grating that, when illuminated with a given light source, diffracts light to produce a three-dimensional reconstruction of the holographic recording. The holographic phase grating may be a non-switchable diffraction grating encoded with a permanent interference pattern, or may be a switchable diffraction grating, where the diffracted light can be modulated by controlling the electric field applied to the holographic recording medium. If desired, multiple holographic phase gratings (holograms) may be recorded within the same volume of holographic medium (e.g., superimposed within the same volume of grating medium). The holographic phase grating may be, for example, a volume hologram or a thin film hologram within the grating medium. The grating medium may include photopolymers, gelatin such as dichromated gelatin, silver halide, holographic polymer dispersed liquid crystals, or other suitable holographic media.

[0035] The diffraction grating on waveguide 26 may include a holographic phase grating such as a volume hologram or a thin film hologram, a meta-grating, or any other desired diffraction grating structure. The diffraction grating on waveguide 26 may also include surface relief gratings formed on one or more surfaces of the substrate within waveguide 26, gratings formed by a pattern of metal structures, etc. The diffraction grating may, for example, include multiple multiplexed gratings (e.g., holograms) that at least partially overlap within the same volume of grating medium (e.g., for diffracting light of different colors and / or light from different input angle ranges at one or more corresponding output angles).

[0036] Optical system 14B may include collimating optics such as collimating lens 34. Collimating lens 34 may include one or more lens elements that help direct image light 22 towards waveguide 26. Although not shown in Figure 2 , if desired, one or more prisms or other optical components may be included between collimating lens 34 and waveguide 26. Alternatively, if desired, collimating lens 34 may be omitted. If desired, display module 14A may be mounted within Figure 1 support structure 20, while optical system 14B may be mounted between portions of support structure 20 (e.g., to form a lens aligned with the eye comfort zone 24). If desired, other mounting arrangements may be used.

[0037] As Figure 2As shown, the light engine 14A can generate image light 22 associated with the image content to be displayed in the eye zone 24. The image light 22 can be collimated using a lens such as a collimating lens 34. The optical system 14B can be used to present the image light 22 output from the light engine 14A to the eye zone 24. If needed, the optical system 14B can include a lens barrel 25, which can include one or more lenses / lens elements, and the lens barrel overlaps with the eye zone 24. In other words, the light 22 can pass through the lens barrel 25 to reach the eye zone 24.

[0038] The optical system 14B can include one or more optical couplers such as an input coupler 28, a cross-coupler 32, and an output coupler 30. In Figure 2 the example, the input coupler 28, the cross-coupler 32, and the output coupler 30 are formed at or on the waveguide 26. The input coupler 28, the cross-coupler 32, and / or the output coupler 30 can be fully embedded in the base layer of the waveguide 26, can be partially embedded in the base layer of the waveguide 26, can be mounted to the waveguide 26 (e.g., mounted to the outer surface of the waveguide 26), etc.

[0039] Figure 2 The example of

[0040] is merely illustrative. One or more of these couplers (e.g., the cross-coupler 32) can be omitted. The optical system 14B can include a plurality of waveguides stacked laterally and / or vertically relative to each other. Each waveguide can include one of the couplers 28, 32, and 30, two of the couplers, all of the couplers, or none of these couplers. If needed, the waveguide 26 can be at least partially curved or bent.

[0040] The waveguide 26 can guide the image light 22 downward along its length via total internal reflection. The input coupler 28 can be configured to couple the image light 22 from the light engine 14A into the waveguide 26, while the output coupler 30 can be configured to couple the image light 22 from within the waveguide 26 to the outside of the waveguide 26 and toward the eye zone 24. If needed, the input coupler 28 can include an input coupling prism. As an example, the light engine 14A can emit the image light 22 toward the optical system 14B in the +Y direction. When the image light 22 impinges on the input coupler 28, the input coupler 28 can redirect the image light 22 such that the light propagates within the waveguide 26 via total internal reflection toward the output coupler 30 (e.g., in the +X direction). When the image light 22 impinges on the output coupler 30, the output coupler 30 can redirect the image light 22 away from the waveguide 26 toward the eye zone 24 (e.g., backward in the Y direction). For example, in a scenario where the cross-coupler 32 is formed at the waveguide 26, the cross-coupler 32 can redirect the image light 22 to one or more directions as the image light 22 propagates downward along the length of the waveguide 26.

[0041] Input coupler 28, cross-coupler 32, and output coupler 30 may be based on reflective and refractive optical devices, or may be based on holographic (e.g., diffractive) optical devices. In an arrangement where couplers 28, 30, and 32 are formed of reflective and refractive optical devices, couplers 28, 30, and 32 may include one or more reflectors (e.g., micromirrors, partial mirrors, shutter-mounted mirrors, or arrays of other reflectors). In an arrangement where couplers 28, 30, and 32 are based on holographic optical devices, couplers 28, 30, and 32 may include diffraction gratings (e.g., volume holograms, surface relief gratings, etc.).

[0042] In a suitable arrangement sometimes described herein as an example, output coupler 30 is formed by a diffraction grating or micromirror (e.g., a volume hologram recorded on a grating medium stacked between transparent polymer waveguide substrates, an array of micromirrors embedded in a polymer layer interposed between transparent polymer waveguide substrates, etc.) embedded within waveguide 26, while input coupler 28 includes a prism mounted to the outer surface of waveguide 26 (e.g., the outer surface defined by the waveguide substrate that contacts the grating medium or polymer layer used to form output coupler 30) or one or more layers of a diffraction grating structure.

[0043] In some embodiments, it may be desirable to mount light engine 14A rotatably and / or laterally such that light engine 14A can be rotated relative to waveguide 26. In particular, the angle of light engine 14A can be adjustable relative to waveguide 26 to ensure that the angle can be moved back to its original position / realigned as needed after device 10 has been used, and / or to allow adjustment of the output of waveguide 26. In Figure 3 An illustrative example of a head-mounted device with a rotatably mounted light engine is shown.

[0044] As Figure 3 shown, light engine 14A may emit light 22 at an angle 51 with respect to surface normal 39 of waveguide 26. To adjust angle 51 and / or the point at which light 22 enters waveguide 26, light engine 14A can be rotated and / or translated in one or more directions.

[0045] For example, light engine 14A can be rotated along curve 44 and / or along curve 49. In particular, when light engine 14A moves along curve 44 and / or curve 49, the light engine can pivot about one or more pivot points. In this way, light engine 14A can be rotated and angle 51 can be adjusted.

[0046] Alternatively or additionally, the optical engine 14A can be translated laterally in the direction 45 (e.g., in the +X direction and the -X direction) and / or in the direction 47 (e.g., in the +Y direction and the -Y direction). By moving the optical engine 14A in one or more of these directions, the point at which the light 22 enters the waveguide 26 can be adjusted, and thus the final image emitted from the waveguide 26 can be adjusted.

[0047] Although not shown in Figure 3 the optical engine 14A can alternatively or additionally be rotated and / or translated relative to the Z-axis if desired.

[0048] By adjusting the position of the optical engine 14A, one or more characteristics of the image produced by the optical engine 14A and the waveguide 26 can be adjusted, such as image brightness, distortion, white point, resolution, or other characteristics.

[0049] Regardless of the direction of rotation and / or translation of the optical engine 14A, any suitable locator can be incorporated into the device 10 to move the optical engine 14A. An exemplary example of a fastener for moving the optical engine around a pivot point is shown in Figure 4 .

[0050] As Figure 4 shown, the device 10 can include the optical engine 14A on a base 36. The base 36 can be formed of metal, plastic, or other suitable material. The base 36 can be coupled to a structure 40. The structure 40 can be formed of a rigid material, such as metal, plastic, or other rigid material. In some exemplary embodiments, the structure 40 can be part of a support structure or housing of the device 10 (such as Figure 1 the support structure 20). As a specific example, in an embodiment where the support structure 20 has a spectacle frame shape, the structure 40 can be the temple / bar portion of the support structure 20. However, this is merely exemplary. Generally, the structure 40 can be any suitable rigid structure coupled to the base 36.

[0051] The base 36 can be coupled to the structure 40 using a fastener 42. The fastener 42 can be a screw, a pin, or other suitable fastener. In particular, the fastener 42 can pass through the structure 40 and through at least a portion of the base 36. The base 36 can also rotate about a rotational pivot point 38. For example, the base 36 can be coupled to the structure 40 or another suitable part of the device 10 at the rotational pivot point 38, such as by a shoulder screw or other fastener that allows the base 36 to rotate about the point 38.

[0052] By tightening and loosening the fastener 42, the base 36 can be moved closer to and farther from the structure 40 and can rotate about the pivot point 38. In particular, the base 36 can rotate along the curve 44, thereby changing the angle of the light emitted by the light engine 14A into the waveguide 26.

[0053] A spring 43, which can be a conical spring or other suitable type of spring, can be incorporated between the base 36 and the structure 40. The spring 43 can provide a preload between the base 36 and the structure 40. However, the spring 43 can be omitted if desired.

[0054] If desired, a locking mechanism can be used to lock the base 36 (and thus the light engine 14A) into a desired position. For example, a lock nut, such as lock nut 53, can be used at the end of the fastener 42 to maintain the position of the fastener 42. Alternatively or additionally, a series of stops can be incorporated, such as at the pivot point 38, to maintain the position of the base 36 at a certain angle, and / or a reworkable adhesive can be used to maintain the position of the base 36. In this way, the light engine 14A can be repositioned (e.g., the angle of the light engine 14A relative to the waveguide 26 can be adjusted), and the position of the light engine 14A can be locked in the desired position.

[0055] Although Figure 4 the base 36 and the light engine 14A are shown moving along a single axis (e.g., along the curve 44), this is merely illustrative. If desired, one or more additional fasteners can be incorporated into the device to adjust the base 36 and the light engine 14A in one or more additional directions (e.g., Figure 3 any direction in the rotational and / or translational directions). For example, the additional fasteners can move the base 36 and the light engine 14A along another curve (e.g., along a curve perpendicular to the curve 44) or laterally (e.g., along the Y-axis, Z-axis, and / or X-axis). In this way, the position of the light engine 14A can be adjusted in multiple directions.

[0056] Using the fastener 42 to adjust the position of the light engine 14A relative to the waveguide 26 is merely illustrative. Generally, the light engine 14A can be mounted in any desired manner, and any suitable locator can be used to rotate and / or translate the light engine 14A relative to the waveguide 26. In some embodiments, flexures can be used to position the light engine 14A. Exemplary examples are shown in Figure 5 .

[0057] As Figure 5As shown, a flexure 46 (also referred to herein as a flexure bracket 46) can be coupled to waveguide 26 and base 36. Flexure 46 can be formed of copper, gold, silver, or other suitable flexible material. In some embodiments, flexure 46 can be flexible enough to allow adjustment of the optical engine 14A, while being rigid enough to maintain the position of the optical engine after adjustment of the optical engine 14A.

[0058] Flexure 46 can be deflected / bent along direction 48 (e.g., in the +X direction and the -X direction). Thus, base 36 and thus optical engine 14A can be rotated along curve 44, and the angle of the light emitted by optical engine 14A into waveguide 26 can be adjusted. After optical engine 14A has been moved, the rigidity of flexure 46 can maintain the position of the optical engine. Alternatively or additionally, a separate locking mechanism can be incorporated into device 10 to maintain the position of the optical engine after the optical engine 14A has been adjusted.

[0059] Although not shown in Figure 5 , flexure 46 can be combined with a fastener (such as Figure 4 fastener 42) to further control the movement of optical engine 14A. In some illustrative examples, after the position of optical engine 14A has been adjusted using flexure 46, a fastener can be used to lock the position of the optical engine. However, if desired, as an alternative or supplement to locking the position of the optical engine 14A, a fastener can be used to move the optical engine 14A.

[0060] Although Figure 5 shows base 36 and optical engine 14A moving along a single axis (e.g., along curve 44), this is merely illustrative. If desired, one or more additional flexures, fasteners, and / or other components can be incorporated into the device to adjust base 36 and optical engine 14A in one or more additional directions (e.g., Figure 3 some or all of the directions shown in

[0061] Generally, any suitable locator can be used to move optical engine 14A relative to waveguide 26 in one or more directions. For example, as shown in the illustrative example of Figure 6 , a hinge can be used to couple base 36 to waveguide 26.

[0062] In particular, as shown in Figure 6As shown, hinge 52 can couple the base 36 to an optional structural member 50. The structural member 50 can be a structure formed of metal, plastic, or other materials adjacent to the waveguide 26. Alternatively, hinge 52 can be directly coupled to a portion of the waveguide 26.

[0063] The hinge 52 can be a four-bar linkage having rods 54A, 54B, 54C, and 54D. In this way, the angle and distance of the optical engine 14A can be adjusted relative to the waveguide 26. For example, the optical engine 14A can rotate relative to the waveguide 26 along the curve 44, and / or can be laterally moved along the X-axis and / or Y-axis. If desired, multiple hinge structures can be incorporated between the optical engine 14A and the waveguide 26 to allow the optical engine 14A to rotate and / or translate in multiple directions (e.g., Figure 3 one or more of the directions shown in).

[0064] Figure 6 The example where the hinge 52 is a four-bar linkage is merely illustrative. Generally, the hinge 52 can be any suitable type of hinge to couple the base 36 to the waveguide 26 and allow the optical engine 14A to move relative to the waveguide 26.

[0065] Although not shown in Figure 6 the hinge 52 can be combined with flexures (such as Figure 5 flexure 46) and / or fasteners (such as Figure 4 fastener 42) to further control the movement of the optical engine 14A.

[0066] In some illustrative embodiments, the base 36 can be mounted to a curved track and can move along the curved track to change the rotation and distance of the optical engine 14A relative to the waveguide 26. An illustrative example is shown in Figure 7 the figure.

[0067] As Figure 7 shown, the base 36 can be mounted to a curved track 56. The curved track 56 can be formed of metal, plastic, or other suitable materials. In some embodiments, the curved track 56 can be mounted to one or more support structures of the device 10, or can be formed by one or more support structures of the device 10.

[0068] The base 36 can move along the curved track 56, thereby changing the angle of the optical engine 14A (e.g., as the optical engine 14A moves along the curve 58) and the distance between the optical engine 14A and the waveguide 26 in the X-direction and Y-direction.

[0069] Optionally, a lead screw 57 can be used to move the base 36 along the curved track 56. The lead screw 57 can be manually adjusted and / or attached to a motor that can rotate the lead screw 57 to move the base 36 along the curved track 56. However, the use of the lead screw 57 is merely illustrative, and the base 36 can be moved along the curved track 56 in any suitable manner.

[0070] Figure 7 The shape of the curved track 56 in is merely illustrative. Generally, the curved track 56 can have any suitable curved shape to allow rotational and / or lateral adjustment of the optical engine 14A relative to the waveguide 26.

[0071] Additionally, if desired, multiple curved tracks and / or other adjustment structures (e.g., Figures 4 to 6 one or more of the adjustment structures in Figures 4 to 6 ) can be incorporated into the device 10 to move the optical engine 14A in multiple directions (e.g., Figure 3 any of the directions in Figure 3 ) for rotation and / or translation.

[0072] As another illustrative example, cams and screws can be used as locators to rotate and / or translate the optical engine 14A. Figure 8A and Figure 8B show illustrative examples of cams and screws that can be used to adjust the optical engine 14A.

[0073] As Figure 8A shown, the cam 60 and the screw 61 can be coupled to the back of the base 36, opposite the waveguide 26. A structure 62, which can be a plastic structure, a metal structure, or a structure of another suitable material, can be adjacent to and in contact with the cam 60.

[0074] As Figure 8B shown, the cam 60 can have a surface 66 whose radius varies along the circumference of the cam 60. Thus, when the cam 60 rotates (as shown by the arrow 64), the portions of the cam 60 having a large radius will push the screw 61 away from the structure 62. Additionally, the screw 61 can be biased towards the structure 62, such as using a spring or other biasing member, to allow the screw 61 to move closer to the structure 62 when the portions of the cam 60 having a smaller radius contact the structure 62. As Figure 8A shown, this movement of the cam 60 causes the base 36 to pivot about the pivot point 38 and causes the optical engine 14A to move along the curve 44. Thus, the optical engine 14A can be rotated and / or translated relative to the waveguide 26.

[0075] Although Figure 8A and Figure 8BIt is shown that the cam 60 moves the light engine 14A along the curve 44, but this is merely illustrative. In general, one or more cam structures can be incorporated into the device 10 to move the light engine 14A in any desired direction (e.g., in any of the directions shown in Figure 3 ). For example, additional cams and screws can be incorporated on the side of the base 36 to move the light engine 14A along another curve (such as the curve 49 of Figure 3 ).

[0076] As another illustrative example, a rack and pinion can be used as a positioner to rotate and / or translate the light engine 14A. An illustrative example of a rack and pinion that can be used to adjust the light engine 14A is shown in Figure 9 .

[0077] As Figure 9 shown, a circular gear 68 (also referred to as a pinion 68) can be coupled to the base 36 and a linear gear 70 (also referred to as a rack 70). The teeth of the pinion 68 can engage the teeth of the rack 70, and the pinion 68 can move along the rack 70 in the direction 72 (e.g., the +X direction and the -X direction). When the pinion 68 moves along the rack 70, the base 36 can pivot about the pivot point 38, thereby causing the light engine 14A to move along the curve 44. In this way, a rack and pinion can be used to rotate and / or translate the light engine 14A relative to the waveguide 26.

[0078] Although Figure 9 it is shown that a rack and pinion moves the light engine 14A along the curve 44, this is merely illustrative. In general, one or more rack and pinion systems can be incorporated into the device 10 to move the light engine 14A in any desired direction (e.g., in any of the directions shown in Figure 3 ). For example, additional rack and pinion systems can be incorporated on the side of the base 36 to move the light engine 14A along another curve (such as the curve 49 of Figure 3 ).

[0079] Furthermore, although Figure 9 it is shown that the rack is linear, this is merely illustrative. If desired, the rack 70 can be curved.

[0080] As another illustrative example, a piezoelectric actuator can be used as a positioner to rotate and / or translate the light engine 14A. Figure 10 An illustrative example of a piezoelectric actuator that can be used to adjust the light engine 14A is shown in

[0081] As Figure 10 shown, the piezoelectric actuator 74 can be incorporated between the structure 40 and the base 36. In operation, a voltage can be applied (e.g., through a control circuit, such as Figure 1to a piezoelectric actuator 74 of the control circuit 16), causing the piezoelectric actuator 74 to expand / deflect. As a result, the base 36 can rotate about the pivot point 38, and the optical engine 14A can move along the curve 44. In this way, the piezoelectric actuator can be used to adjust the position of the optical engine 14A relative to the waveguide 26 based on the amount of voltage applied to the piezoelectric actuator 74.

[0082] After the voltage is applied, the piezoelectric actuator 74 can be stable. Thus, the position of the optical engine 14A relative to the waveguide 26 can be stable. However, if desired, a locking mechanism such as a fastener or an adhesive can be incorporated to maintain the position of the optical engine 14A relative to the waveguide 26.

[0083] Although Figure 10 illustrates the piezoelectric actuator moving the optical engine 14A along the curve 44, this is merely illustrative. Generally, one or more piezoelectric actuators can be incorporated into the device 10 to move the optical engine 14A in any desired direction (e.g., in any of the directions shown in Figure 3 ). For example, additional piezoelectric actuators can be incorporated on the side of the base 36 to move the optical engine 14A along another curve (such as Figure 3 the curve 49).

[0084] Figures 4 to 10 The locator shown is merely illustrative. In general, any suitable locator can be used to rotate and / or translate the optical engine 14A in one or more directions. As additional illustrative examples, a worm drive mechanism, a rack and pinion system with a bend, a spring mechanism, or any other suitable locator can be used to rotate and / or translate the optical engine 14A.

[0085] Regardless of the locator used to adjust one or more optical engines, an illustrative method of rotating and / or translating an optical engine is shown in Figure 11 .

[0086] As Figure 11 shown in the method 76, at step 78, one or more sensors (such as Figure 1 the sensor 18) of an electronic device (e.g., Figure 1 the device 10) can make measurements. For example, a Hall effect sensor, an interferometer, an encoder, a strain gauge, an inertial measurement unit (IMU), and / or other suitable sensors can be used to measure the position of the optical engine (e.g., the optical engine 14A) in the device. These measurements can be used to determine whether the optical engine has shifted relative to the waveguide (e.g., the waveguide 26) from its original position (or desired position).

[0087] Alternatively or additionally, one or more sensors may measure the output of a display including an optical engine. For example, a camera or other optical sensor may measure Figure 2 the output light 22, such as by redirecting some of the light using a secondary output coupler. These measurements may determine the brightness, distortion, white point, or other characteristics of the light output from the display.

[0088] At step 80, the position of the optical engine may be adjusted based on the sensor measurements. For example, if the position of the optical engine is measured and determined to have shifted or be in an undesirable position, the position of the optical engine may be adjusted. In particular, the optical engine may be moved in one or more directions (e.g., Figure 3 any one or more of the directions shown in, or along the Z-axis).

[0089] One or more of the positioners of Figures 4 to 10 or other suitable positioners may be used to rotate and / or translate the optical engine. For example, a motor, an electronic actuator, or other electronic components may be used to move the optical engine using the positioners. In particular, a control circuit in an electronic device (such as Figure 1 the control circuit 16) may send a signal to the motor or other components to adjust the position of the optical engine, such as to tighten a fastener ( Figure 4 ), move a flexure ( Figure 5 ), move the optical engine around a hinge ( Figure 6 ), move the optical engine along a track (such as by using a lead screw) ( Figure 7 ), adjust a cam system (Figure 8), adjust a rack and pinion system ( Figure 9 ), adjust a piezoelectric actuator ( Figure 10 ), and / or otherwise adjust the position of the optical engine. In this way, the optical engine may be repositioned relative to the waveguide.

[0090] As an alternative to repositioning the optical engine to counteract the shift of the optical engine, the optical engine may be moved to adjust the output of the display. In particular, the optical engine may be rotated and / or translated to adjust the brightness, resolution, white point, or other characteristics of the display. In some embodiments, the optical engine may be adjusted to transform an image from the display, such as geometrically transform the image.

[0091] The adjustment made at step 80 can be performed while not using the electronic device (such as when the device is charging, when the device is in a sleep state or otherwise in a standby mode, or when the device is powered on or off). Alternatively, the adjustment at step 80 can be performed when the device is transitioning between environments, such as when the user is moving from indoors to outdoors, or when the content displayed on the display is changing, such as changing between text and video. However, these examples are merely illustrative. Generally, the position of the light engine in the device can be adjusted during any suitable operation of the device.

[0092] Although Figure 11 automatic adjustment of the light engine based on sensor measurements has been described, this is merely illustrative. As an example, if desired, the light engine can be automatically adjusted based on any suitable input, such as changing the settings of device 10, or the content displayed on the display in device 10. Alternatively or additionally, the light engine can be manually adjusted, such as by manually tightening a fastener ( Figure 4 ), moving a flexure ( Figure 5 ), moving the light engine around a hinge ( Figure 6 ), moving the light engine along a track (such as by using a lead screw ( Figure 7 )), adjusting a cam system (Figure 8), adjusting a rack and pinion system ( Figure 9 ), and / or otherwise manually adjusting the position of the light engine. After the position of the light engine has been adjusted, the position of the light engine can be locked in place. For example, a lock nut, a series of stoppers, and / or a reworkable adhesive can be used to maintain the position of the light engine relative to the waveguide.

[0093] As discussed, multiple locators can be incorporated into the electronic device to adjust the position of the light engine in more than one direction. Figure 12 An illustrative example is shown in

[0094] As Figure 12 shown, the fastener 42 can be used to adjust the light engine 14A along the curve 44 (e.g., as Figure 4 shown). Additionally, the fastener 88 can be used to laterally translate the light engine 14A in the direction 89 (e.g., in the +Y direction and -Y direction). The members 84 and 86 can be coupled to the base 36, and the fastener 88 can pass through the member 86 into the rear of the base 36. For example, the fastener 88 can be a screw, a pin, or other suitable fastener. By using a motor or manually tightening and loosening the fastener 88, the base 36 can be moved in the direction 89, thereby moving the light engine 14A closer to and farther from the waveguide 26.

[0095] While in Figure 12is not shown, but a locking mechanism can be used to lock the base 36 (and thus the optical engine 14A) in a desired position. For example, lock nuts can be used at the ends of the fasteners 42 and / or the fasteners 88 to maintain the position of the fasteners 42. Alternatively or additionally, a series of stoppers can be incorporated, such as at the pivot point 38 or within the base 36, to maintain the position of the base 36 at a certain angle or a certain lateral position, and / or a reworkable adhesive can be used to maintain the position of the base 36. In this way, the optical engine 14A can be repositioned (e.g., the angle of the optical engine 14A relative to the waveguide 26 can be adjusted, and / or the optical engine 14A can be moved further away from or closer to the waveguide 26), and the optical engine 14A can be locked in the desired position.

[0096] Although Figure 12 it is shown that the fastener 42 rotates the optical engine 14A along the curve 44 and the fastener 88 translates the optical engine 14A along the Y-axis, this is merely illustrative. If desired, a curved track (e.g., Figure 7 the curved track 56) or another suitable mechanism can be used to allow the optical engine 14A to rotate in multiple directions.

[0097] As another illustrative example, multiple flexures can be used to adjust the optical engine in multiple directions. As shown in the illustrative example of Figure 13 flexures 93 formed of copper, gold, silver, or other suitable flexible materials can extend from the flexure 90 (previously discussed in conjunction with Figure 5 ). In addition to the flexure 90 being movable along the direction 92 to rotate the optical engine 14A along the curve 44, the flexure 93 can also be moved along the direction 94 to rotate the optical engine 14A along the curve 49. However, this is merely illustrative. If desired, the flexure 93 can be used to allow the optical engine 14A to rotate in the Z direction.

[0098] Figure 12 and Figure 13 the examples of Figures 4 to 10 are merely illustrative of combinations of locators that can be used to rotate and / or translate the optical engine in multiple directions. Generally, any suitable locator (such as any of the locators in

[0099] Although Figures 4 to 13The light engine 14A on the base 36 has been shown, and the light engine is adjusted by one or more locators, but this is merely illustrative. If desired, the light engine 14A can be directly adjusted by the locators (e.g., the locators can be in direct contact with the light engine 14A), or multiple structures can be incorporated between the locators and the light engine 14A.

[0100] In addition, although Figures 3 to 13 adjusting the light engine 14A has been described, this is merely illustrative. In some embodiments, individual components within the adjustable light engine 14A (such as one or more lenses, one or more light sources, and / or one or more prisms) can be adjusted. For example, one or more of the locators such as those used Figures 4 to 10 can rotate and / or laterally translate one or more of these individual components relative to the waveguide 26. Alternatively or additionally, the lens barrel that overlaps the ocular region (e.g., Figure 2 the lens barrel 25) can be rotated and / or laterally translated relative to the waveguide 26. In this way, the image displayed to the ocular region can be corrected or otherwise adjusted.

[0101] According to an embodiment, an electronic device is provided that includes a head-mounted support structure and a display coupled to the head-mounted support structure. The display includes: a light engine configured to emit light; a waveguide having an input coupler configured to couple the light into the waveguide and an output coupler configured to couple the light out of the waveguide and toward the ocular region; and a locator coupled to the light engine. The locator is configured to rotate the light engine relative to the waveguide.

[0102] According to another embodiment, the locator is optionally configured to laterally translate the light engine relative to the waveguide.

[0103] According to another embodiment, the light engine is optionally coupled to a base, and the locator optionally includes a fastener coupled to the base, wherein the light engine is configured to be rotated by adjusting the fastener.

[0104] According to another embodiment, the fastener optionally passes through an opening in a portion of the head-mounted support structure, and the electronic device optionally includes a biasing spring interposed between the portion of the head-mounted support structure and the base.

[0105] According to another embodiment, the base optionally has a front portion facing the waveguide, an opposite rear portion, and side portions extending from the front portion to the rear portion, wherein the fastener is a first fastener coupled to one of the side portions of the base, and the locator optionally includes a second fastener coupled to the rear portion of the base, and wherein the light engine is configured to be laterally translated by adjusting the second fastener.

[0106] According to another embodiment, the light engine is optionally coupled to the base, the locator optionally includes a flexure coupled to the base, and the light engine is configured to be rotated by bending the flexure.

[0107] According to another embodiment, the base has a front portion optionally facing the waveguide, an opposite rear portion, and side portions extending from the front portion to the rear portion, the flexure is a first flexure coupled to one of the side portions of the base, and the locator optionally includes a second flexure coupled to the rear portion of the base.

[0108] According to another embodiment, the locator optionally includes a hinge between the waveguide and the light engine.

[0109] According to another embodiment, the hinge is optionally a four-bar linkage hinge.

[0110] According to another embodiment, the locator optionally includes a curved track, and the light engine is configured to be rotated by moving the light engine along the curved track.

[0111] According to another embodiment, the locator optionally includes a lead screw, and the light engine is configured to move along the curved track by adjusting the lead screw.

[0112] According to another embodiment, the light engine is optionally coupled to the base, the locator optionally includes a cam and a screw coupled to the base, and the light engine is configured to be rotated by adjusting the cam and the screw.

[0113] According to another embodiment, the light engine is optionally coupled to the base, the locator optionally includes a pinion and a rack engaging the pinion, and the light engine is configured to be rotated by moving the pinion along the rack.

[0114] According to another embodiment, the locator optionally includes a piezoelectric actuator, and the piezoelectric actuator is configured to rotate the light engine in response to a voltage applied to the piezoelectric actuator.

[0115] According to another embodiment, the electronic device optionally includes a sensor in the head-mounted support structure, and the sensor is configured to measure the position of the light engine relative to the waveguide.

[0116] According to another embodiment, the electronic device optionally includes a motor in the head-mounted support structure, and the motor is configured to rotate the light engine in response to the measured position of the light engine.

[0117] According to another embodiment, the electronic device optionally includes a sensor in the head-mounted support structure, the sensor is configured to measure the light coupled out from the output coupler, and the light engine is configured to be rotated relative to the waveguide in response to the measured light.

[0118] According to an embodiment, a display is provided, the display includes: a light engine configured to emit light; a waveguide having an input coupler configured to couple the light into the waveguide and an output coupler configured to couple the light out of the waveguide; and a locator coupled to the light engine, wherein the locator is configured to adjust the angle of the light engine relative to the waveguide.

[0119] According to another embodiment, the locator is a first locator, and the display optionally includes a second locator configured to laterally translate the light engine relative to the waveguide.

[0120] According to an embodiment, a head-mounted device is provided, the head-mounted device includes: a light engine configured to emit light; a waveguide configured to guide the light to an eye comfort zone; a first locator configured to adjust the position of the light engine relative to the waveguide in a first direction; and a second locator configured to adjust the position of the light engine relative to the waveguide in a second direction different from the first direction.

[0121] The foregoing is merely illustrative and various modifications may be made to the described embodiments. The foregoing embodiments may be implemented independently or in any combination.

Claims

1. An electronic device, comprising: Head-mounted support structure; and a display coupled to the head mounted support structure, the display comprising: a light engine configured to emit light, a waveguide having an input coupler configured to couple the light into the waveguide and having an output coupler configured to couple the light out of the waveguide toward an eye region; and A positioner is coupled to the light engine, wherein the positioner is configured to rotate the light engine relative to the waveguide. 2 . The electronic device of claim 1 , wherein the positioner is further configured to translate the light engine laterally relative to the waveguide.

3. The electronic device of claim 1 , wherein the light engine is coupled to a base, and the positioner comprises: A fastener is coupled to the base, wherein the light engine is configured to be rotated by adjusting the fastener.

4. The electronic device of claim 3, wherein the fastener passes through an opening in a portion of the head-mounted support structure, the electronic device further comprising: A bias spring is interposed between the portion of the head mounted support structure and the base.

5. The electronic device of claim 3, wherein the base has a front facing the waveguide, an opposite rear, and sides extending from the front to the rear, wherein the fastener is a first fastener coupled to one of the sides of the base, and the positioner further comprises: A second fastener is coupled to the rear portion of the base, wherein the light engine is configured to be laterally translated by adjusting the second fastener.

6. The electronic device of claim 1 , wherein the light engine is coupled to a base, and the positioner comprises: A flexure is coupled to the base, wherein the light engine is configured to be rotated by bending the flexure.

7. The electronic device of claim 6, wherein the base has a front facing the waveguide, an opposite rear, and sides extending from the front to the rear, wherein the flexure is a first flexure coupled to one of the sides of the base, and the positioner further comprises: A second flexure is coupled to the rear portion of the base.

8. The electronic device of claim 1, wherein the positioner comprises a hinge between the waveguide and the light engine.

9. The electronic device of claim 8, wherein the hinge is a four-bar hinge.

10. The electronic device of claim 1, wherein the positioner comprises a curved track, and the light engine is configured to be rotated by moving the light engine along the curved track. 11 . The electronic device of claim 10 , wherein the positioner further comprises a lead screw, and the light engine is configured to move along the curved track by adjusting the lead screw.

12. The electronic device of claim 1, wherein the light engine is coupled to a base, and the positioner comprises: A cam and a screw are coupled to the base, wherein the light engine is configured to be rotated by adjusting the cam and the screw.

13. The electronic device of claim 1 , wherein the light engine is coupled to a base, and the positioner comprises: a pinion gear coupled to the base; and A rack meshes with the pinion, wherein the light engine is configured to be rotated by moving the pinion along the rack.

14. The electronic device of claim 1, wherein the positioner comprises a piezoelectric actuator, and the piezoelectric actuator is configured to rotate the light engine in response to a voltage applied to the piezoelectric actuator.

15. The electronic device according to claim 1, further comprising: A sensor is within the head mounted support structure, wherein the sensor is configured to measure a position of the light engine relative to the waveguide.

16. The electronic device according to claim 15, further comprising: A motor is provided in the head mounted support structure, wherein the motor is configured to rotate the light engine in response to the measured position of the light engine.

17. The electronic device according to claim 1, further comprising: A sensor is in the head mounted support structure, wherein the sensor is configured to measure the light coupled out of the output coupler, and the light engine is configured to be rotated relative to the waveguide in response to the measured light.

18. A display, comprising: a light engine configured to emit light; a waveguide having an input coupler configured to couple the light into the waveguide and having an output coupler configured to couple the light out of the waveguide; and A positioner is coupled to the light engine, wherein the positioner is configured to adjust an angle of the light engine relative to the waveguide.

19. The display of claim 18, wherein the locator is a first locator, the display further comprising: A second positioner is configured to translate the light engine laterally relative to the waveguide.

20. A head mounted device, comprising: a light engine configured to emit light; a waveguide configured to guide the light to an eye area; a first positioner configured to adjust a position of the light engine relative to the waveguide in a first direction; and A second positioner is configured to adjust the position of the light engine relative to the waveguide in a second direction different from the first direction.

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