TW202308245A - Multi-color visible light source including integrated vcsels and integrated photonic cavities - Google Patents

Abstract

A visible light source includes a substrate, a vertical-cavity surface-emitting laser including an active semiconductor region configured to emit infrared light and a first reflector configured to reflect the infrared light emitted by the active semiconductor region, a second reflector configured to reflect the infrared light and form a vertical cavity for the infrared light with the first reflector, and one or more micro-resonators configured to receive the infrared light and generate visible light in one or more colors using the infrared light through optical parametric oscillation. The visible light source also includes one or more output couplers configured to couple the visible light in one or more colors from the one or more micro-resonators into free space or into a photonic integrated circuit.

Description

Multicolor visible light source including integrated vertical-cavity surface-emitting laser and integrated photonic cavity

The present invention relates to a multicolor visible light source including an integrated vertical cavity surface-emitting laser and an integrated photonic cavity. Cross References to Related Applications

This patent application claims the U.S. provisional application titled "VISIBLE LIGHT SOURCE INCLUDING INTEGRATED VCSELS AND INTEGRATED PHOTONIC CAVITIES" filed on April 26, 2021. Benefit and Priority of Patent Application No. 63/179,913 and U.S. Non-Provisional Application No. 17/344744, filed June 10, 2021. The disclosure of the above application is hereby incorporated by reference in its entirety for all purposes.

Semiconductor light-emitting devices, such as light-emitting diodes (light-emitting diodes), convert electrical energy into light energy and provide many benefits over other light sources, such as reduced size, improved durability, and increased efficiency and brightness. emitting diode (LED), micro LED, resonant cavity LED (RCLED), vertical-cavity surface-emitting laser (VCSEL) and vertical external cavity surface-emitting laser (vertical external cavity surface emitting laser; VECSEL). Semiconductor light emitting devices can be used as light sources in many display systems, such as televisions, computer monitors, laptops, tablets, smartphones, projection systems, and wearable electronic devices. For example, micro LEDs or VCSELs that emit light of different colors (eg, red, green, and blue) can be used to form sub-pixels of display panels in display systems such as near-eye display systems. Micro LEDs, VCSELs, and other semiconductor light emitting devices can also be deployed in various sensor systems, such as those for depth sensing, three-dimensional sensing, object tracking (e.g., hand tracking or face tracking), and the like .

The present invention generally relates to visible light sources. More particularly, and without limitation, the present invention relates to integrated vertical-cavity surface-emitting laser (VCSEL)-pumped visible light sources comprising optical parametric oscillations (OPO) configured to generate Optical resonators for visible light. The visible light sources disclosed herein can be used, for example, in backlight unit (BLU) displays and active display panels. Various inventive embodiments are described herein, including apparatuses, assemblies, systems, methods, structures, materials, procedures, and the like.

According to some embodiments, a visible light source may include: a substrate; a first reflector and a second reflector on the substrate, wherein the first reflector and the second reflector are configured to reflect infrared light and vertically arranged to form a vertical cavity; an active region positioned in the vertical cavity and configured to emit infrared light; a microresonator positioned on the substrate and configured to receive light emitted by the active region and an output coupler configured to couple the visible light generated in the microresonator out of the microresonator.

According to some embodiments, a visible light source array may include: a CMOS base plate including driving circuits formed thereon; and a visible light source array formed on a substrate and directly or indirectly bonded to the CMOS base plate . Each visible light source in the visible light source array is individually addressable by the drive circuit and includes: a first reflector and a second reflector configured to reflect infrared light and form a vertical cavity; an active region, located in the vertical cavity and configured to emit infrared light; a microresonator configured to receive the infrared light emitted by the active region and generate visible light via optical parametric oscillation; and an output coupler configured to to couple the visible light generated in the microresonator out of the microresonator.

According to some embodiments, a visible light source may include: a substrate; a vertical cavity surface-emitting laser on the substrate and including an active semiconductor region configured to emit infrared light and configured to reflect light emitted by the active semiconductor region. A first reflector of the infrared light emitted by the semiconductor region; a second reflector configured to reflect the infrared light, the first reflector and the second reflector forming a vertical cavity for the infrared light one or more microresonators located on the substrate and configured to receive the infrared light and use the infrared light to produce visible light exhibiting one or more colors through optical parametric oscillation; and one or more output couplers that Configured to couple the visible light in one or more colors from the one or more microresonators into free space or into a photonic integrated circuit.

According to some embodiments, a visible light source array may include: a substrate including a driving circuit formed thereon; and a die or a wafer directly or indirectly bonded to the driving circuit. The die or wafer may include an array of visible light sources formed thereon. Each visible light source in the array of visible light sources is individually addressable by the drive circuitry and includes: a vertical cavity formed by a first reflector and a second reflector, the first reflector and the second reflector a device configured to reflect infrared light; an active region located in the vertical cavity and configured to emit infrared light; one or more microresonators configured to receive the infrared light and use the infrared light to pass an optical parameter oscillating to produce visible light in one or more colors; and one or more output couplers configured to couple the visible light in one or more colors from the one or more microresonators into free space or one or more in multiple waveguides.

According to some embodiments, a visible light source array may include: a substrate including a driving circuit formed thereon; and a die or a wafer directly or indirectly bonded to the driving circuit. The die or wafer may include an array of visible light sources formed thereon. Each visible light source in the array of visible light sources is individually addressable by the drive circuitry and includes: a vertical cavity formed by a first reflector and a second reflector, the first reflector and the second reflector a device configured to reflect infrared light; an active region located in the vertical cavity and configured to emit infrared light; a microresonator configured to receive the infrared light and use the infrared light to generate visible light via optical parametric oscillation and an output coupler configured to couple the visible light from the microresonator into free space or a waveguide. A first microresonator in a first visible light source in the array of visible light sources and a second microresonator in a second visible light source in the array of visible light sources may have different sizes, different shapes, different materials, or A combination and configured to produce visible light of different colors.

This Summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used in isolation to determine the scope of the claimed subject matter. The subject matter should be understood by reference to this disclosure, in appropriate portions, of the entire specification, any or all drawings and each claim. The foregoing, along with other features and examples, will be described in more detail below in the following specification, claims, and accompanying drawings.

The present invention generally relates to visible light sources. More particularly, and without limitation, the present invention relates to integrated vertical-cavity surface-emitting laser (VCSEL)-pumped visible light sources comprising optical parametric oscillation (OPO) configured to generate visible light using infrared optical resonator. Various inventive embodiments are described herein, including devices, systems, components, wafers, dies, methods, structures, materials, procedures, and the like.

判定，其中 η _EQE 為光源（例如，雷射或微LED）之外部量子效率（external quantum efficiency；EQE）且可與載子（例如，電子）注入效率、內部量子效率及光萃取效率（light extraction efficiency；LEE）之乘積成比例。 η _in 為可見顯示光自光源至波導中之入耦效率。 η _out 為可見顯示光自波導朝向觀看者之眼睛的出耦效率。為了改良例如光學系統（例如，顯示系統）之亮度、解析度及效率，通常需要具有小像素間距（例如，小於約20或約10 μm）、高亮度、高動態範圍、可控制發射方向、可個別定址能力、大色域及製造可擴展性之可見光源陣列。 Semiconductor light emitting devices can be used in many optical systems, such as display systems and sensor systems. For example, in some display systems, visible display light emitted from a visible light source (eg, a diode laser array or a micro light emitting diode (micro LED) array) can be directed to project onto a user's eye. In a waveguide display system, visible display light emitted from a visible light source can be coupled into a display (eg, a waveguide display) for delivering images to the eyes of a viewer. The total efficiency η _tot of the waveguide display system can be obtained by

Determined, where η _EQE is the external quantum efficiency (external quantum efficiency; EQE) of the light source (for example, laser or micro LED) and can be compared with carrier (for example, electron) injection efficiency, internal quantum efficiency and light extraction efficiency (light extraction efficiency; LEE) proportional to the product. η _in is the incoupling efficiency of visible display light from the light source to the waveguide. _ηout is the outcoupling efficiency of visible display light from the waveguide towards the viewer's eye. To improve, for example, the brightness, resolution, and efficiency of optical systems (eg, display systems), it is generally desirable to have a small pixel pitch (eg, less than about 20 or about 10 μm), high brightness, high dynamic range, controllable emission direction, Arrays of visible light sources with individual addressability, large color gamut and manufacturing scalability.

However, fabricating such visible light sources can be challenging. For example, LEDs and organic LEDs (OLEDs) may have fundamental limitations in brightness. It can be extremely difficult to manufacture VCSELs with high efficiency for some visible colors (eg, green). Fabricating visible laser sources for multiple colors on the same chip or wafers can be even more challenging. Furthermore, current visible light source architectures can often have large footprints and may not be suitable for individually addressable high density source arrays for high resolution displays. The integration of III-V semiconductor devices with photonic integrated circuits (PICs) may present additional manufacturing challenges.

According to some embodiments, the visible light source may include a VCSEL that can emit light in the near-infrared (NIR) or other infrared (IR) bands with high efficiency. NIR light may generally be referred to as IR light hereinafter. Visible light sources can also include microresonators that can convert IR light due to degenerate four-wave mixing within the microresonator (a third-order nonlinear optical process also known as optical parametric oscillation (OPO)) into visible light. In some embodiments, a microresonator can be positioned inside or outside the VCSEL cavity and aligned with the VCSEL, where the IR light emitted by the VCSEL can be coupled directly or through a coupling structure (e.g., a grating coupler or nanoresonator). into the microresonator. In some embodiments, IR light emitted by a VCSEL can be coupled into a waveguide by a coupling structure (e.g., a grating coupler or a nanoresonator), and can then be coupled from the waveguide into a microresonator, e.g., via a waveguide coupler . Microresonators may include, for example, microring resonators, photonic crystal point defect cavities, photonic crystal ring (line defect) cavities, plasmonic resonators, and the like. Visible light generated by degenerate four-wave mixing in a microresonator can be coupled out of the microresonator into a waveguide via edge coupling by a coupling structure (e.g., a grating, or a dielectric or metallic scatterer placed near the microresonator) , or coupled into free space via a vertical coupling.

In some embodiments, the device can include an array of visible light sources, where the visible light sources can emit visible light of different colors, such as red, blue, and green. In one example, each visible light source may include a microresonator, and the microresonators (and/or VCSELs) in some visible light sources may be different from the microresonators (and/or VCSELs) in some other visible light sources, Different visible light sources can emit light of different colors. In some embodiments, each visible light source in the array of visible light sources can be configured or can be configurable to emit light of a different color. In one example, each visible light source in an array of visible light sources can include a pumped VCSEL and multiple microresonators (e.g., vertically arranged) with different parameters, where each of the multiple microresonators can be configured to produce different colors of visible light, and in some embodiments, each microresonator in a plurality of microresonators can be tuned (e.g., by a thermo-optic or electro-optic tuner) to independently adjust the light emitted by the microresonator The corresponding intensity of visible light produced. In some embodiments, the visible light source in the visible light source array can include a pumped VCSEL having a tunable cavity and can be tuned to emit pump light having different wavelengths, and the visible light source can also include a VCSEL having multiple resonant modes and thus Microresonators that generate visible light of different colors can be produced using pump light having different wavelengths.

The techniques disclosed herein can achieve the performance required for display applications. For example, due to the vertical configuration of each visible light source and the compactness of the configuration of the visible light source array, a small-pitch multi-color pixelated array can be achieved, which can be used as a liquid crystal display (liquid crystal display; LCD) with local dimming capable backlight unit (BLU), or can be used as an active display panel. The polarization of output light from a visible light source can be highly controlled, for example, by the design of the outcoupling structures (eg, gratings, diffusers, etc.). The structure of visible light sources can be designed to generate light at any visible wavelength using the OPO process, and thus can be used to provide International Telecommunication Union (ITU) Recommendation BT.2020 (Rec. 2020) color gamut or even larger. Direct electronic control of each visible light source provides individual addressability, high contrast and fast response. The integration of pump light and OPO components provides an overall compact, low-profile planar structure suitable for AR/VR applications. The visible light sources disclosed herein can also be used to provide red, green, and blue light to other on-wafer photonic integrated circuits when edge coupling is used.

Additionally, the visible light sources disclosed herein may have tunable manufacturability. For example, the visible light sources disclosed herein can use established integration methods for integrating (e.g., bonding) near-infrared (NIR) VCSELs with SiN, SiC, AlN, LiNbO ₃ , or SiON materials for photonic integrated circuits. technology to manufacture. The visible light sources disclosed herein use a VCSEL structure suitable for substrate liftoff for integration. Pixelated arrays can be fabricated at the tunable wafer level, including fabrication of VCSEL and PIC devices, bonding, or the like.

As used herein, visible light may refer to light visible to the human eye, such as light having a wavelength between about 400 nm and about 750 nm. Infrared light may generally refer to light having a wavelength greater than about 750 nm. Near infrared (NIR) light may refer to IR light having a wavelength between, for example, about 750 nm and about 2500 nm.

The visible light sources described herein can be used in conjunction with various technologies such as artificial reality systems. Artificial reality systems, such as head-mounted display (HMD) or heads-up display (HUD) systems, typically include a display configured to present artificial images depicting objects in the virtual environment. The display can present virtual objects or combine images of real objects with virtual objects, such as in virtual reality (VR), augmented reality (AR) or mixed reality (MR) applications. For example, in an AR system, a user can view a virtual reality through, for example, see-through transparent display glasses or lenses (often referred to as optical see-through) or by viewing a displayed image of the surrounding environment captured by a camera (often referred to as video see-through). Both the displayed image of the object (eg, computer-generated image (CGI)) and the displayed image of the surrounding environment. In some AR systems, an LED-based display subsystem may be used to present artificial images to the user.

In the following description, for purposes of explanation, specific details are set forth in order to provide a thorough understanding of examples of the present disclosure. It will be apparent, however, that various examples may be practiced without these specific details. For example, devices, systems, structures, assemblies, methods, and other components may be shown in block diagram form as components in order not to obscure the examples with unnecessary detail. In other instances, well-known devices, procedures, systems, structures and techniques may be shown without unnecessary detail in order not to obscure the examples. The drawings and descriptions are not intended to be limiting. The terms and expressions which have been used in the present invention are terms of description and not of limitation, and in the use of such terms and expressions, there is no intention to exclude any equivalents or parts of the features shown and described. The word "example" is used herein to mean "serving as an example, instance, or illustration." Any particular example or design described herein as an "example" is not necessarily to be construed as preferred or advantageous over other particular examples or designs.

1 is a simplified block diagram of an example of an artificial reality system environment 100 including a near- eye display 120 according to certain embodiments. The artificial reality system environment 100 shown in FIG. 1 can include a near-eye display 120, an optional external imaging device 150, and an optional input/output interface 140, each of which can be coupled to an optional control Taiwan 110. Although FIG. 1 shows an example of an AR environment 100 including a near-eye display 120, an external imaging device 150, and an input/output interface 140, any number of these components may be included in the AR environment 100, Or any of the components may be omitted. For example, there may be multiple near-eye displays 120 , which may be monitored by one or more external imaging devices 150 in communication with console 110 . In some configurations, the augmented reality environment 100 may not include the external imaging device 150 , the optional input/output interface 140 , and the optional console 110 . In alternative configurations, different or additional components may be included in the augmented reality system environment 100 .

The near-eye display 120 may be a head-mounted display that presents content to the user. Examples of content presented by the near-eye display 120 include one or more of images, video, audio, or any combination thereof. In some embodiments, audio may be presented via an external device (e.g., speakers and/or headphones) that receives audio information from near-eye display 120, console 110, or both, and presents the audio based on that audio information. material. The near-eye display 120 may include one or more rigid bodies, which may be rigidly or non-rigidly coupled to each other. Rigid couplings between rigid bodies may cause the coupled rigid bodies to act as a single rigid entity. A non-rigid coupling between rigid bodies allows the rigid bodies to move relative to each other. In various embodiments, near-eye display 120 may be implemented in any suitable form factor, including a pair of glasses. Some specific examples of near-eye display 120 are described further below with respect to FIGS. 2 and 3 . Additionally, in various embodiments, the functionality described herein may be used in headsets that combine images of the environment external to near-eye display 120 with artificial reality content (eg, computer-generated images). Therefore, the near-eye display 120 can use the generated content (eg, image, video, sound, etc.) to amplify the image of the physical real-world environment outside the near-eye display 120 to present the augmented reality to the user.

In various embodiments, the near-eye display 120 may include one or more of the display electronics 122 , the display optics 124 , and the eye-tracking unit 130 . In some embodiments, the near-eye display 120 may also include one or more positioners 126 , one or more position sensors 128 and an inertial measurement unit (IMU) 132 . In various embodiments, the near-eye display 120 may omit any of the eye-tracking unit 130, the locator 126, the position sensor 128, and the IMU 132, or include additional elements. Additionally, in some embodiments, near-eye display 120 may include elements that combine the functionality of the various elements described in connection with FIG. 1 .

Display electronics 122 may display images to a user or facilitate displaying images to a user based on data received from, for example, console 110 . In various specific examples, the display electronics 122 may include one or more display panels, such as a liquid crystal display (liquid crystal display; LCD), an organic light-emitting diode (OLED) display, an inorganic light-emitting diode (inorganic light-emitting diode (ILED) display, micro light-emitting diode (μLED) display, active-matrix OLED (AMOLED), transparent OLED (TOLED) or some other display. For example, in one embodiment of the near-eye display 120, the display electronics 122 may include a front TOLED panel, a rear display panel, and optical components (e.g., attenuators, polarizers, or diffractive or spectral film). Display electronics 122 may include pixels to emit light of a dominant color such as red, green, blue, white or yellow. In some embodiments, the display electronics 122 can display a three-dimensional (3-dimensional; 3D) image through the stereoscopic effect generated by the two-dimensional panel to generate a subjective perception of image depth. For example, the display electronics 122 may include left and right displays positioned in front of the user's left and right eyes, respectively. The left and right displays may present copies of the image that are shifted horizontally relative to each other to create a stereoscopic effect (ie, the user viewing the image's perception of depth).

In some embodiments, display optics 124 may optically display image content (e.g., using optical waveguides and couplers), or amplify image light received from display electronics 122, correcting optical errors associated with image light , and present the corrected image light to the user of the near-eye display 120 . In various embodiments, display optics 124 may include one or more optical elements, such as substrates, optical waveguides, apertures, Fresnel lenses, convex lenses, concave lenses, filters, input/output couplers, or Any other suitable optical elements that may affect the image light emitted from the display electronics 122 . Display optics 124 may include a combination of different optical elements, as well as mechanical couplings to maintain the relative spacing and orientation of the optical elements in the combination. One or more optical elements in display optics 124 may have an optical coating, such as an anti-reflective coating, a reflective coating, a filter coating, or a combination of different optical coatings.

Amplification of image light by display optics 124 may allow display electronics 122 to be physically smaller, weigh less and consume less power than larger displays. Additionally, zooming in increases the field of view of the displayed content. The amount by which image light is magnified by display optics 124 can be varied by adjusting, adding, or removing optical elements from display optics 124 . In some embodiments, display optics 124 may project a displayed image to one or more image planes that may be farther away from the user's eyes than near-eye display 120 .

Display optics 124 may also be designed to correct for one or more types of optical errors, such as two-dimensional optical errors, three-dimensional optical errors, or any combination thereof. Two-dimensional errors may include optical aberrations that occur in two dimensions. Example types of two-dimensional errors may include barrel distortion, pincushion distortion, longitudinal chromatic aberration, and lateral chromatic aberration. Three-dimensional errors may include optical errors that occur in three dimensions. Example types of three-dimensional errors may include spherical aberration, coma, curvature of field, and astigmatism.

Locators 126 may be objects that are located in particular locations on near-eye display 120 relative to each other and relative to a reference point on near-eye display 120 . In some implementations, the console 110 may identify the locator 126 in images captured by the external imaging device 150 to determine the location, orientation, or both of the artificial reality headset. Locators 126 may be LEDs, corner cube reflectors, reflective markers, a type of light source that contrasts with the environment in which near-eye display 120 operates, or any combination thereof. In embodiments where locator 126 is an active component such as an LED or other type of light emitting device, locator 126 may emit light in the visible light band (eg, approximately 380 nm to 750 nm), the infrared (IR) band (eg, , about 750 nm to 1 mm), in the ultraviolet band (eg, about 10 nm to about 380 nm), in another part of the electromagnetic spectrum, or any combination of parts of the electromagnetic spectrum.

External imaging device 150 may include one or more cameras, one or more video cameras, any other device capable of capturing images including one or more of locators 126, or any combination thereof. Additionally, external imaging device 150 may include one or more filters (eg, to increase the signal-to-noise ratio). External imaging device 150 may be configured to detect light emitted or reflected from locator 126 in the field of view of external imaging device 150 . In specific examples where locators 126 include passive elements (e.g., retroreflectors), external imaging device 150 may include a light source that illuminates some or all of locators 126 that can retroreflect light to the light source in the external imaging device 150 . Slow calibration data may be communicated from external imaging device 150 to console 110, and external imaging device 150 may receive one or more calibration parameters from console 110 to adjust one or more imaging parameters (e.g., focal length, focus, frame rate, sensor temperature, shutter speed, aperture, etc.).

The position sensor 128 can generate one or more measurement signals in response to the movement of the near-eye display 120 . Examples of position sensors 128 may include accelerometers, gyroscopes, magnetometers, other motion detection or error correction sensors, or any combination thereof. For example, in some embodiments, position sensor 128 may include multiple accelerometers to measure translational motion (e.g., forward/backward, up/down, or left/right) and to measure rotational Multiple gyroscopes for motion such as pitch, yaw or roll. In some specific examples, the various position sensors may be oriented orthogonally to each other.

IMU 132 may be an electronic device that generates rapid calibration data based on measurement signals received from one or more of position sensors 128 . Position sensor 128 may be located external to IMU 132, internal to IMU 132, or any combination thereof. Based on one or more measurement signals from one or more position sensors 128 , IMU 132 may generate quick calibration data indicating an estimated position of near-eye display 120 relative to an initial position of near-eye display 120 . For example, IMU 132 may integrate measurement signals received from accelerometers over time to estimate a velocity vector, and integrate the velocity vector over time to determine an estimated location of a reference point on near-eye display 120 . Alternatively, IMU 132 may provide the sampled measurement signal to console 110, which may determine quick calibration data. While a reference point may generally be defined as a point in space, in various embodiments, a reference point may also be defined as a point within near-eye display 120 (eg, the center of IMU 132 ).

Eye tracking unit 130 may include one or more eye tracking systems. Eye tracking may refer to determining the position of an eye relative to the near-eye display 120, including the orientation and orientation of the eye. An eye tracking system may include an imaging system to image one or more eyes, and optionally include a light emitter that can generate light directed toward the eye so that light reflected by the eye can be captured by the imaging system. For example, eye-tracking unit 130 may include an incoherent or coherent light source (eg, a laser diode) that emits light in the visible or infrared spectrum, and a camera that captures the light reflected by the user's eyes. As another example, eye-tracking unit 130 may capture reflected radio waves emitted by a miniature radar unit. Eye tracking unit 130 may use low power light transmitters that emit light at frequencies and intensities that do not damage the eyes or cause physical discomfort. Eye tracking unit 130 may be configured to increase the contrast of eye images captured by eye tracking unit 130 while reducing the overall power consumed by eye tracking unit 130 (e.g., reducing and power consumed by the imaging system). For example, in some implementations, eye tracking unit 130 may consume less than 100 milliwatts of power.

The near-eye display 120 may use the orientation of the eyes to, for example, determine the user's inter-pupillary distance (IPD), determine gaze direction, introduce depth cues (e.g., blurry images outside the user's primary line of sight), collect information about Heuristic information for user interaction in VR media (e.g., time spent on any particular entity, object, or frame that varies depending on the stimulus to which it is exposed), based in part on at least one of the user's eyes some other function of the orientation, or any combination thereof. Since the orientation of the user's two eyes can be determined, the eye tracking unit 130 may be able to determine where the user is looking. For example, determining the gaze direction of the user may include determining a point of convergence based on the determined orientations of the user's left and right eyes. The point of convergence may be the point where two foveal axes of the user's eyes intersect. The user's gaze direction may be the direction of a line passing through the point of convergence and the midpoint between the pupils of the user's eyes

The input/output interface 140 may be a device that allows a user to send action requests to the console 110 . An action request may be a request to perform a specific action. For example, an action request may start or end an application or perform a specific action within an application. The input/output interface 140 may include one or more input devices. Example input devices may include a keyboard, mouse, game controller, glove, buttons, touch screen, or any other suitable device for receiving action requests and communicating the received action requests to console 110 . Action requests received by input/output interface 140 may be communicated to console 110 where actions corresponding to the requested actions may be performed. In some embodiments, the input/output interface 140 can provide haptic feedback to the user according to commands received from the console 110 . For example, the input/output interface 140 may provide haptic feedback when an action request is received or when the console 110 has performed the requested action and communicated the command to the input/output interface 140 . In some embodiments, an external imaging device 150 may be used to track the input/output interface 140, such as tracking the orientation or position of a controller (which may include, for example, an IR light source) or a user's hand to determine the user's motion. In some embodiments, the near-eye display 120 may include one or more imaging devices to track the input/output interface 140, such as tracking the orientation or position of a controller or a user's hand to determine the user's motion.

Console 110 may provide content to near-eye display 120 for presentation to the user based on information received from one or more of external imaging device 150 , near-eye display 120 , and input/output interface 140 . In the example shown in FIG. 1 , the console 110 may include an app store 112 , a headset tracking module 114 , an artificial reality engine 116 , and an eye tracking module 118 . Some embodiments of console 110 may include different or additional modules than those described in connection with FIG. 1 . The functionality described further below may be distributed among the components of console 110 in different ways than described here.

In some embodiments, console 110 may include a processor and a non-transitory computer-readable storage medium storing instructions executable by the processor. A processor may include multiple processing units that execute instructions in parallel. A non-transitory computer-readable storage medium can be any memory such as a hard drive, removable memory, or solid-state drive (eg, flash memory or dynamic random access memory (DRAM)) body. In various embodiments, the modules of the console 110 described in connection with FIG. 1 can be encoded as instructions in a non-transitory computer-readable storage medium that, when executed by the processor, cause the processor to perform the following steps: function described.

The application store 112 can store one or more application programs for the console 110 to execute. An application program may include a set of instructions that, when executed by a processor, generate content for presentation to a user. The content generated by the application may be input received from the user in response to movement of the user's eyes, or input received from the input/output interface 140 . Examples of applications may include gaming applications, conferencing applications, video playback applications, or other suitable applications.

The headphone tracking module 114 can use the slow calibration information from the external imaging device 150 to track the movement of the near-eye display 120 . For example, the headset tracking module 114 may use the observed locators from the slow calibration information and a model of the near-eye display 120 to determine the location of a reference point for the near-eye display 120 . The headset tracking module 114 can also use the location information from the quick calibration information to determine the location of the reference point of the near-eye display 120 . Additionally, in some embodiments, the headset tracking module 114 may use portions of the fast calibration information, the slow calibration information, or any combination thereof to predict the future position of the near-eye display 120 . The headset tracking module 114 may provide the estimated location or the predicted future location of the near-eye display 120 to the artificial reality engine 116 .

The artificial reality engine 116 can execute the application program in the artificial reality system environment 100, and receive the position information of the near-eye display 120, the acceleration information of the near-eye display 120, the speed information of the near-eye display 120, and the near-eye display 120 from the headset tracking module 114. The predicted future location, or any combination thereof. The artificial reality engine 116 may also receive estimated eye position and orientation information from the eye tracking module 118 . Based on the received information, the artificial reality engine 116 may determine content to provide to the near-eye display 120 for presentation to the user. For example, if the received information indicates that the user has looked to the left, the artificial reality engine 116 may generate content for the near-eye display 120 that reflects the movement of the user's eyes in the virtual environment. In addition, the augmented reality engine 116 can take an action within an application executing on the console 110 in response to an action request received from the input/output interface 140 and provide feedback to the user indicating that the action has been taken. The feedback can be visual or auditory feedback via the near-eye display 120 , or tactile feedback via the input/output interface 140 .

The eye tracking module 118 can receive eye tracking data from the eye tracking unit 130 and determine the position of the user's eyes based on the eye tracking data. The position of the eye may include the orientation, orientation, or both of the eye relative to the near-eye display 120 or any element thereof. Since the axis of rotation of the eye changes depending on the orientation of the eye in its socket, determining the orientation of the eye in its socket may allow the eye tracking module 118 to more accurately determine the orientation of the eye.

2 is a perspective view of an example of a near - eye display in the form of an HMD device 200 for implementing some of the examples disclosed herein. The HMD device 200 may be part of, for example, a VR system, an AR system, an MR system, or any combination thereof. The HMD device 200 may include a main body 220 and a head strap 230 . Figure 2 shows the bottom side 223, the front side 225 and the left side 227 of the main body 220 in a perspective view. The head strap 230 may have an adjustable or extendable length. There may be sufficient space between the main body 220 of the HMD device 200 and the head strap 230 to allow the user to mount the HMD device 200 on the user's head. In various embodiments, HMD device 200 may include additional components, fewer components, or different components. For example, instead of head strap 230 , in some embodiments, HMD device 200 may include eyeglass temples and temple tips as shown, for example, in FIG. 3 below.

HMD device 200 may present media to a user that includes virtual and/or augmented views of a physical real-world environment with computer-generated elements. Examples of media presented by HMD device 200 may include images (eg, two-dimensional (2D) or three-dimensional (3D) images), video (eg, 2D or 3D video), audio, or any combination thereof. The images and videos may be presented to each eye of the user by one or more display assemblies (not shown in FIG. 2 ) enclosed in the body 220 of the HMD device 200 . In various embodiments, one or more display assemblies may include a single electronic display panel or multiple electronic display panels (eg, one display panel for each eye of a user). Examples of electronic display panels may include, for example, LCDs, OLED displays, ILED displays, µLED displays, AMOLEDs, TOLEDs, some other display, or any combination thereof. HMD device 200 may include two orbital regions.

In some embodiments, the HMD device 200 may include various sensors (not shown), such as depth sensors, motion sensors, position sensors, and eye tracking sensors. Some of these sensors can use structured light patterns for sensing. In some implementations, the HMD device 200 may include an input/output interface for communicating with a console. In some embodiments, the HMD device 200 may include a virtual reality engine (not shown), which can execute applications in the HMD device 200 and receive depth information, position information of the HMD device 200 from various sensors. information, acceleration information, velocity information, predicted future position, or any combination thereof. In some implementations, information received by the virtual reality engine may be used to generate signals (eg, display commands) for one or more display assemblies. In some implementations, HMD device 200 may include locators (not shown, such as locator 126 ) located in fixed positions on body 220 relative to each other and relative to a reference point. Each of the locators can emit light that can be detected by an external imaging device.

3 is a perspective view of an example of a near - eye display 300 in the form of a pair of glasses for implementing some of the examples disclosed herein. Near-eye display 300 may be a particular implementation of near-eye display 120 of FIG. 1 and may be configured to operate as a virtual reality display, an augmented reality display, and/or a mixed reality display. The near-eye display 300 may include a frame 305 and a display 310 . Display 310 may be configured to present content to a user. In some embodiments, display 310 may include display electronics and/or display optics. For example, as described above with respect to near-eye display 120 of FIG. 1 , display 310 may include an LCD display panel, an LED display panel, or an optical display panel (eg, a waveguide display assembly).

The near-eye display 300 may further include various sensors 350 a , 350 b , 350 c , 350 d , and 350 e on or within the frame 305 . In some embodiments, the sensors 350a to 350e may include one or more depth sensors, motion sensors, position sensors, inertial sensors, or ambient light sensors. In some embodiments, the sensors 350a-350e may include one or more image sensors configured to generate image data representing different fields of view in different directions. In some embodiments, sensors 350 a - 350 e can be used as input devices to control or affect displayed content of near-eye display 300 and/or provide an interactive VR/AR/MR experience to a user of near-eye display 300 . In some embodiments, the sensors 350a-350e can also be used for stereoscopic imaging.

In some embodiments, the near-eye display 300 may further include one or more illuminators 330 to project light into the physical environment. The projected light can be associated with different frequency bands (eg, visible, infrared, ultraviolet, etc.) and can be used for various purposes. For example, the illuminator 330 can project light into a dark environment (or an environment with low intensity infrared light, ultraviolet light, etc.) to assist the sensors 350a to 350e in capturing images of different objects in the dark environment. In some embodiments, illuminators 330 may be used to project certain light patterns onto objects within the environment. In some embodiments, illuminator 330 may be used as a locator, such as locator 126 described above with respect to FIG. 1 .

In some specific examples, the near-eye display 300 may also include a high-resolution camera 340 . Camera 340 may capture images of the physical environment in the field of view. The captured image can be processed, for example, by a virtual reality engine (e.g., artificial reality engine 116 of FIG. Displayed to the user for AR or MR applications.

4 illustrates an example of an optical see-through augmented reality system 400 including a waveguide display , according to certain embodiments. The augmented reality system 400 may include a projector 410 and a combiner 415 . Projector 410 may include a light source or image source 412 and projector optics 414 . In some embodiments, the light source or image source 412 may include one or more of the micro LED devices described above. In some embodiments, the image source 412 may include a plurality of pixels for displaying virtual objects, such as an LCD display panel or an LED display panel. In some embodiments, image source 412 may include a light source that produces coherent or partially coherent light. For example, the image source 412 may include laser diodes, VCSELs, LEDs, and/or micro LEDs as described above. In some embodiments, image source 412 may include a plurality of light sources (eg, the micro LED arrays described above) each emitting monochromatic image light corresponding to a primary color (eg, red, green, or blue). In some embodiments, image source 412 can include three two-dimensional micro-LED arrays, where each two-dimensional micro-LED array can include micro-LEDs configured to emit light of a primary color (eg, red, green, or blue). In some embodiments, image source 412 may include an optical pattern generator, such as a spatial light modulator. Projector optics 414 may include one or more optical components that may condition light from image source 412 , such as expand, collimate, scan, or project light from image source 412 to combiner 415 . The one or more optical components may include, for example, one or more lenses, liquid lenses, mirrors, apertures and/or gratings. For example, in some embodiments, image source 412 can include one or more one-dimensional micro-LED arrays or elongated two-dimensional micro-LED arrays, and projector optics 414 can include one or more one-dimensional micro-LED arrays configured to scan or One or more 1D scanners (eg, micromirrors or micromirrors) that elongate a 2D array of micro-LEDs to produce an image frame. In some embodiments, projector optics 414 may include a liquid lens (eg, a liquid crystal lens) having a plurality of electrodes that allows light from image source 412 to be scanned.

The combiner 415 may include an input coupler 430 for coupling light from the projector 410 into the substrate 420 of the combiner 415 . The combiner 415 can transmit at least 50% of the light in the first wavelength range and reflect at least 25% of the light in the second wavelength range. For example, the first wavelength range may be visible light from about 400 nm to about 650 nm, and the second wavelength range may be in the infrared band, eg, from about 800 nm to about 1000 nm. The input coupler 430 may include a volume holographic grating, a diffractive optical element (DOE) (eg, a surface relief grating), a sloped surface of the substrate 420 , or a refractive coupler (eg, a wedge or a dimple). For example, the input coupler 430 may comprise a reflective volume Bragg (Bragg) grating or a transmissive volume Bragg grating. For visible light, the input coupler 430 can have a coupling efficiency greater than 30%, 50%, 75%, 90%, or higher. The light coupled into the substrate 420 may propagate within the substrate 420 via, for example, total internal reflection (TIR). Substrate 420 may be in the form of a lens of a pair of eyeglasses. Substrate 420 may have a flat or curved surface, and may include one or more types of dielectric materials, such as glass, quartz, plastic, polymer, poly(methyl methacrylate) (PMMA), crystal or ceramic. The thickness of the substrate can range, for example, from less than about 1 mm to about 10 mm or more. Substrate 420 may be transparent to visible light.

Substrate 420 may include or be coupled to a plurality of output couplers 440 each configured to extract from substrate 420 at least a portion of the light guided by and propagating within substrate 420 and to extract Light 460 is directed to eye sockets 495 where eyes 490 of a user of augmented reality system 400 may be located when augmented reality system 400 is in use. Multiple output couplers 440 can duplicate the exit pupil to increase the size of the eye socket 495 so that the displayed image is visible in a larger area. Like the input coupler 430, the output coupler 440 may include a grating coupler (eg, a volume hologram or a surface relief grating), other diffractive optical elements, gratings, or the like. For example, output coupler 440 may comprise a reflective volume Bragg grating or a transmissive volume Bragg grating. Output coupler 440 may have different coupling (eg, diffraction) efficiencies at different orientations. Substrate 420 may also allow light 450 from the environment in front of combiner 415 to pass through with little or no loss. Output coupler 440 may also allow light 450 to pass through with very little loss. For example, in some implementations, output coupler 440 may have very low diffraction efficiency for light 450 such that light 450 may be refracted or otherwise pass through output coupler 440 with very little loss, and thus may Has a higher intensity than the extracted light 460 . In some implementations, the output coupler 440 can have high diffraction efficiency for the light 450 and can diffract the light 450 in certain desired directions (ie, diffraction angles) with very little loss. Thus, the user may be able to view a combined image of the environment in front of the combiner 415 and the image of the virtual object projected by the projector 410 .

5A illustrates an example of a near-eye display (NED) device 500 including a waveguide display 530 according to certain embodiments . NED device 500 may be an example of near-eye display 120, augmented reality system 400, or another type of display device. NED device 500 may include light source 510 , projection optics 520 and waveguide display 530 . The light source 510 may include sets of light emitters of different colors, such as a set of red light emitters 512 , a set of green light emitters 514 , and a set of blue light emitters 516 . Red emitters 512 are organized in an array; green emitters 514 are organized in an array; and blue emitters 516 are organized in an array. The size and spacing of the light emitters in light source 510 may be small. For example, each light emitter can have a diameter of less than 2 μm (eg, about 1.2 μm), and the pitch can be less than 2 μm (eg, about 1.5 μm). Therefore, the number of light emitters in each of red emitter 512, green emitter 514, and blue emitter 516 may be equal to or greater than the number of pixels in a displayed image, such as 960×720, 1280×720, 1440× 1080, 1920×1080, 2160×1080, or 2560×1080 pixels. Therefore, display images can be generated by the light sources 510 simultaneously. Scanning elements may not be used in NED device 500 .

Before reaching waveguide display 530, light emitted by light source 510 may be conditioned by projection optics 520, which may include an array of lenses. Projection optics 520 may collimate or focus light emitted by light source 510 into waveguide display 530 , which may include a coupler 532 for coupling light emitted by light source 510 into waveguide display 530 . Light coupled into waveguide display 530 may propagate within waveguide display 530 via, for example, total internal reflection as described above with respect to FIG. 4 . The coupler 532 can also couple a portion of the light propagating within the waveguide display 530 out of the waveguide display 530 and toward the user's eye 590 .

5B illustrates an example of a near - eye display (NED) device 550 including a waveguide display 580 according to certain embodiments. In some embodiments, NED device 550 may use scanning mirror 570 to project light from light source 540 into an image field where user's eyes 590 may be located. NED device 550 may be an example of near-eye display 120, augmented reality system 400, or another type of display device. The light source 540 may include one or more columns or rows of light emitters of different colors, such as multiple columns of red light emitters 542 , multiple columns of green light emitters 544 and multiple columns of blue light emitters 546 . For example, red light emitter 542, green light emitter 544, and blue light emitter 546 may each include N columns, each column including, for example, 2560 light emitters (pixels). Red emitters 542 are organized in an array; green emitters 544 are organized in an array; and blue emitters 546 are organized in an array. In some embodiments, light source 540 may include a single row of light emitters for each color. In some embodiments, light source 540 can include multiple rows of light emitters for each of red, green, and blue, where each row can include, for example, 1080 light emitters. In some embodiments, the size and/or pitch of light emitters in light source 540 may be relatively large (e.g., about 3 to 5 μm), and thus light source 540 may not include sufficient light emission to simultaneously produce a complete display image device. For example, the number of light emitters for a single color may be less than the number of pixels in a displayed image (eg, 2560x1080 pixels). The light emitted by light source 540 may be a collection of collimated or diverging beams.

Light emitted by light source 540 may be conditioned by various optical devices such as collimating lenses or freeform optics 560 before reaching scan mirror 570 . Free-form optical element 560 may comprise, for example, a faceted facet or another light-folding element that may direct light emitted by light source 540 toward scanning mirror 570, such as to direct light emitted by light source 540 The direction of propagation of the light changes, for example, by about 90° or more. In some embodiments, freeform optics 560 can be rotatable to scan light. Scanning mirror 570 and/or freeform optics 560 may reflect and project light emitted by light source 540 to waveguide display 580, which may include coupler 582 for coupling light emitted by light source 540 into waveguide display 580 . Light coupled into waveguide display 580 may propagate within waveguide display 580 via, for example, total internal reflection as described above with respect to FIG. 4 . The coupler 582 may also couple a portion of the light propagating within the waveguide display 580 out of the waveguide display 580 and toward the user's eye 590 .

The scanning mirror 570 may include a micro-electro-mechanical system (MEMS) mirror or any other suitable mirror. Scanning mirror 570 is rotatable to scan in one or two dimensions. As scanning mirror 570 rotates, light emitted by light source 540 can be directed to different areas of waveguide display 580 so that a complete display image can be projected onto waveguide display 580 and directed by waveguide display 580 to the user in each scan cycle. Eyes 590. For example, in embodiments where light source 540 includes light emitters for all pixels in one or more columns or rows, scanning mirror 570 may be rotated in a row or column direction (e.g., x or y direction) to scan image. In embodiments where light source 540 includes light emitters for some but not all pixels in one or more columns or rows, scanning mirror 570 may be in both column and row directions (e.g., both x and y directions) Rotate to project a display image (for example, using a raster-type scan pattern).

The NED device 550 can operate in a predefined display period. A display period (eg, a display cycle) may refer to the duration for which a full image is scanned or projected. For example, the display period may be the inverse of the desired frame rate. In the NED device 550 including the scanning mirror 570, the display period may also be referred to as a scanning period or a scanning cycle. Light generation by light source 540 may be synchronized with the rotation of scanning mirror 570 . For example, each scan cycle may include multiple scan steps, wherein the light source 540 may generate a different light pattern in each respective scan step.

During each scan cycle, as the scan mirror 570 rotates, a displayed image may be projected onto the waveguide display 580 and the user's eye 590 . The actual color value and light intensity (eg, brightness) of a given pixel location of a displayed image may be the average of the three colored (eg, red, green and blue) light beams illuminating that pixel location during a scan period. After a scan cycle is complete, scan mirror 570 may return to an initial position to project light for the previous columns of the next displayed image, or may rotate in the reverse direction or in a scan pattern to project light for the next displayed image, wherein The new set of drive signals may be fed to light source 540 . The same procedure may be repeated as the scan mirror 570 rotates in each scan cycle. Thus, different images can be projected to the user's eye 590 in different scan cycles.

6 illustrates an example of an image source assembly 610 in a near-eye display system 600 , according to certain embodiments. Image source assembly 610 can include, for example, a display panel 640 that can generate a display image to be projected to a user's eye, and can project the display image generated by display panel 640 onto a waveguide display as described above with respect to FIGS. 4-5B . Projector 650. The display panel 640 may include a light source 642 and a driver circuit 644 for the light source 642 . Light source 642 may include, for example, light source 510 or 540 . Projector 650 may include freeform optics 560, scanning mirror 570, and/or projection optics 520, such as those described above. The near-eye display system 600 may also include a controller 620 that controls the light source 642 and the projector 650 (eg, the scanning mirror 570 ) synchronously. Image source assembly 610 can generate image light and output the image light to a waveguide display (not shown in FIG. 6 ), such as waveguide display 530 or 580 . As described above, a waveguide display can receive image light at one or more input coupling elements and guide the received image light to one or more output coupling elements. The input and output coupling elements may include, for example, diffraction gratings, holographic gratings, oscillating gratings, or any combination thereof. The input coupling element can be chosen such that total internal reflection occurs with a waveguide display. The output coupling element couples a portion of the total total internally reflected image light out of the waveguide display.

As described above, light source 642 may include a plurality of light emitters configured in an array or matrix. Each light emitter may emit monochromatic light, such as red light, blue light, green light, infrared light, or the like. While RGB colors are often discussed in this disclosure, the embodiments described herein are not limited to using red, green, and blue as primary colors. Other colors may also be used as primary colors for the near-eye display system 600 . In some embodiments, a display panel according to an embodiment can use more than three primary colors. Each pixel in light source 642 may include three sub-pixels including a red light source, a green light source, and a blue light source, where each light source may include, for example, a laser (e.g., VCSEL), a micro LED, a resonant cavity LED (RCLED) or similar. In some embodiments, the light source may include a semiconductor light source, such as a semiconductor laser or a semiconductor LED. Semiconductor LEDs typically include active light emitting layers within layers of semiconductor material. Multiple layers of semiconductor material may comprise different compound materials or the same base material with different dopants and/or different doping densities. For example, the plurality of layers of semiconductor material can include a layer of n-type material, an active region that can include a heterostructure (eg, one or more quantum wells), and a layer of p-type material. Multiple layers of semiconductor material can be grown on the surface of a substrate with a certain orientation. In some embodiments, to improve light extraction efficiency, mesas including at least some of the semiconductor material layers may be formed.

The controller 620 can control the image presentation operation of the image source assembly 610 , such as the operation of the light source 642 and/or the projector 650 . For example, controller 620 may determine instructions for image source assembly 610 to render one or more display images. The instructions may include display instructions and scan instructions. In some embodiments, the display command may include an image file (eg, a bitmap file). Display instructions may be received, for example, from a console, such as console 110 described above with respect to FIG. 1 . The scan command may be used by image source assembly 610 to generate image light. A scan instruction may specify, for example, the type of image light source (eg, monochrome or multicolor), scan rate, orientation of the scanning device, one or more illumination parameters, or any combination thereof. Controller 620 may include a combination of hardware, software, and/or firmware not shown here so as not to obscure other aspects of the invention.

In some embodiments, the controller 620 may be a graphics processing unit (graphics processing unit; GPU) of a display device. In other specific examples, the controller 620 may be other types of processors. Operations by controller 620 may include obtaining content for display and dividing the content into discrete segments. Controller 620 may provide scan instructions to light source 642 that include addresses corresponding to individual source elements of light source 642 and/or electrical biases applied to the individual source elements. Controller 620 may instruct light source 642 to sequentially render discrete segments using light emitters corresponding to one or more columns of pixels in the image that is ultimately displayed to the user. Controller 620 may also instruct projector 650 to make different adjustments to the light. For example, controller 620 may control projector 650 to scan discrete segments to different areas of a coupling element of a waveguide display (eg, waveguide display 580 ), as described above with respect to FIG. 5B . Thus, at the exit pupil of the waveguide display, each discrete portion appears in a different distinct orientation. Although each discrete segment is presented at a distinct time, the presentation and scanning of the discrete segments occurs quickly enough that the user's eye can integrate the different segments into a single image or series of images.

Image processor 630 may be a general purpose processor and/or one or more application specific circuits dedicated to performing the features described herein. In one embodiment, a general-purpose processor can be coupled to memory to execute software instructions that cause the processor to perform certain procedures described herein. In another embodiment, the image processor 630 may be one or more circuits dedicated to performing certain features. Although image processor 630 is shown in FIG. 6 as a separate unit from controller 620 and driver circuit 644 , in other embodiments image processor 630 may be a sub-unit of controller 620 or driver circuit 644 . In other words, in these embodiments, the controller 620 or the driver circuit 644 can perform various image processing functions of the image processor 630 . The image processor 630 can also be called an image processing circuit.

In the example shown in FIG. 6 , light source 642 may be driven by driver circuit 644 based on data or instructions sent from controller 620 or image processor 630 (eg, display and scan instructions). In one particular example, driver circuit 644 may include a circuit panel that connects to and mechanically holds the various light emitters of light source 642 . Light source 642 may emit light according to one or more lighting parameters set by controller 620 and potentially adjusted by image processor 630 and driver circuit 644 . The lighting parameters may be used by light source 642 to generate light. Illumination parameters can include, for example, source wavelength, pulse rate, pulse amplitude, beam type (continuous or pulsed), other parameters that can affect emitted light, or any combination thereof. In some embodiments, the source light generated by light source 642 can include a plurality of red, green, and blue light beams, or any combination thereof.

Projector 650 may perform a set of optical functions, such as focusing, combining, conditioning, or scanning the image light generated by light source 642 . In some embodiments, projector 650 may include a combination assembly, a light adjustment assembly, or a scanning mirror assembly. Projector 650 may include one or more optical components that optically adjust and potentially redirect light from light source 642 . One example of light adjustment may include adjusting light, such as spreading, collimating, correcting one or more optical errors (eg, field curvature, chromatic aberration, etc.), some other light adjustment, or any combination thereof. Optical components of projector 650 may include, for example, lenses, mirrors, apertures, gratings, or any combination thereof.

Projector 650 may redirect the image light via one or more reflective and/or refracted portions of the image light such that the image light is projected toward the waveguide display in certain orientations. The orientation at which image light is redirected toward the waveguide display may depend on the particular orientation of one or more reflective and/or refractive portions. In some embodiments, projector 650 includes a single scanning mirror that scans in at least two dimensions. In other embodiments, projector 650 may include a plurality of scanning mirrors that each scan in directions orthogonal to each other. Projector 650 may raster scan (horizontally or vertically), dual resonant scan, or any combination thereof. In some embodiments, projector 650 may vibrate in a controlled horizontal and/or vertical direction at a specific oscillation frequency to scan in two dimensions and generate a two-dimensional projected image of the media presented to the user's eyes. In other embodiments, projector 650 may include a lens or lens that may serve a similar or the same function as one or more scanning mirrors. In some embodiments, the image source assembly 610 may not include a projector, wherein the light emitted by the light source 642 may be directly incident on the waveguide display.

可取決於影像源412之發光效率、藉由投影器光學件414及輸入耦合器430自影像源412至組合器415中的光耦合效率及輸出耦合器440之輸出耦合效率，且因此可判定為：

(1) 其中

為影像源412之外部量子效率，

為自影像源412至波導（例如，基板420）中之光之入耦效率，且

為藉由輸出耦合器440自波導朝向使用者之眼睛之光之出耦效率。因此，可藉由改良

、

及

中之一或多者來改良基於波導之顯示器之總效率

。 The overall efficiency of a photonic integrated circuit or waveguide-based display (eg, in augmented reality system 400 or NED device 500 or 550 ) can be the product of the efficiencies of the individual components, and can also depend on how the components are connected. For example, the overall efficiency of a waveguide-based display in augmented reality system 400

may depend on the luminous efficiency of image source 412, the light coupling efficiency from image source 412 into combiner 415 via projector optics 414 and input coupler 430, and the output coupling efficiency of output coupler 440, and thus may be determined as :

(1) in

is the external quantum efficiency of the image source 412,

is the incoupling efficiency of light from image source 412 into the waveguide (e.g., substrate 420), and

is the outcoupling efficiency of light through the output coupler 440 from the waveguide towards the user's eye. Therefore, by improving

,

and

one or more of them to improve the overall efficiency of waveguide-based displays

.

An optical coupler (eg, input coupler 430 or coupler 532 ) that couples emitted light from the light source to the waveguide may include, for example, a grating, lens, microlens, aperture. In some embodiments, light from a small light source (eg, a micro LED) can be coupled directly (eg, end-to-end) from the light source to the waveguide without the use of an optical coupler. In some embodiments, optical couplers (eg, lenses or parabolic reflectors) can be fabricated on the light source.

A visible light source, image source, or other display described herein may include one or more LEDs, one or more organic LEDs (OLEDs), one or more VCSELs, one or more RC LEDs, or the like. It is generally desirable for visible light sources to have small pixel size, high brightness, high dynamic range, controllable emission direction, individual addressability, large color gamut coverage, and manufacturing scalability. LEDs and OLEDs can have fundamental limitations in brightness.

VCSELs generally include a light emitting active region in a laser cavity forming a laser resonator. The light-emitting active region may include a quantum well (QW) that emits photons when properly biased. Photons can be confined in the laser cavity by a pair of mirrors, such as distributed Bragg reflection (DBR) mirrors or high-contrast grating (HCG) mirrors. In some embodiments, one DBR mirror can be n-doped and the other DBR mirror can be p-doped. In some embodiments, a p-doped layer and an n-doped layer can be used in the laser cavity and the light-emitting active region can be between the p-doped layer and the n-doped layer. VCSELs can be based on a variety of materials. For example, VCSELs having wavelengths from about 650 nm to about 1300 nm may be based on gallium arsenide (GaAs) wafers with DBRs formed of interleaved GaAs and aluminum gallium arsenide (AlGaAs) layers. In GaAs/AlGaAs VCSELs, the lattice constant of the material does not change significantly with compositional changes, thus allowing multiple lattice-matched epitaxial layers to be grown on GaAs substrates. AlGaAs-based DBRs can have a reflectivity close to 100%, which can efficiently confine photons in the laser cavity. The refractive index of AlGaAs can vary with increasing Al fraction, thus minimizing the number of layers used to form a DBR mirror with high reflectivity. AlGaAs-based DBRs doped with p-type or n-type impurities can also act as current paths. Selective oxidation of the AlGaAs layer adjacent to the QW can laterally confine photons and carriers.

FIG. 7A illustrates an example of a VCSEL 700 . VCSEL 700 may include a substrate 710, such as a GaAs substrate or a GaN substrate. In the illustrated example, an optional bulk DBR 720 may be formed (eg, epitaxially grown) on substrate 710 . The bulk DBR 720 may include multiple alternating layers of different materials with different indices of refraction, such as pairs of AlGaAs/GaAs or AlAs/GaAs layers, and thus may reflect light at the interface between layers of different materials to achieve a higher overall Reflectivity. The bottom DBR 730 may be formed on the bulk DBR 720 or may be part of the bulk DBR 720 . The bottom DBR 730 may similarly include multiple alternating layers of different materials with different refractive indices. The VCSEL 700 can also include a cladding layer 740 , an active region 750 and a cladding layer 760 , wherein the cladding layers 740 and 760 can be p-doped or n-doped and can inject carriers into the active region 750 . The active region 750 may include one or more quantum wells or quantum dots, and a QW barrier layer. Carriers can recombine in the active region 750 to emit photons. Top DBR 770 may be formed on cladding layer 760 and may be similar to bottom DBR 730 . The top DBR 770 and bottom DBR 730 (and bulk DBR 720) can form a plane-parallel laser cavity that can confine photons. The top DBR 770 , cladding layer 760 , active region 750 , cladding layer 740 and bottom DBR 730 can be etched vertically to form individual VCSELs of desired size with desired pitch on bulk DBR 720 and substrate 710 .

VCSEL 700 may have linear dimensions of less than about 100 μm, 50 μm, 30 μm, 20 μm, or 10 μm. For example, in some embodiments, the parallel laser cavity can have a length of about 10 μm. In the example shown in FIG. 7A , the bottom DBR 730 and bulk DBR 720 may have a reflectivity close to 100% in combination to reflect nearly all incident photons. The top DBR 770 can have a reflectivity of less than 100%, so that a portion of the emitted photons can be transmitted out of the laser cavity through the top DBR 770 . VCSEL 700 can emit infrared light with high efficiency and high power, such as from about 1 mW to about 10 mW or more.

Figure 7B illustrates an example of a tunable VCSEL 705 according to certain embodiments. The vertical cavity in the tunable VCSEL 705 can be formed by the first reflector 724 and the second reflector 752, where the first reflector 724 and the second reflector 752 can have a high reflectivity (e.g., >80%, > 85%, >90%, >95%, >99% or higher), and the second reflector 752 may have low reflectivity or may be anti-reflective for visible light.

The tunable VCSEL 705 may include a driver circuit 712 that may be bonded directly or indirectly (eg, via an interposer or thin film transistor layer) to the VCSEL 722. Driver circuitry 712 may include various circuits formed on a silicon substrate, as described above, for example, with respect to FIG. 6 . The driving circuit 712 can be coupled to the electrodes of the VCSEL 722 to drive the VCSEL 722 to generate continuous-wave (CW) or pulsed IR light with a sufficiently long duration. The intensity of the IR light emitted by VCSEL 722 and thus the intensity of visible light from tunable VCSEL 705 can be controlled by the drive current or voltage supplied to VCSEL 722 by drive circuit 712 .

The VCSEL 722 may include a first electrode 732 (eg, an anode or a cathode), a second electrode 734 , and a semiconductor structure (eg, an epitaxial layer) formed between the first electrode 732 and the second electrode 734 . The semiconductor structure can include, for example, a first reflector 724, an active region 726 that can emit IR light, and other semiconductor layers (not labeled in FIG. 7B ), such as cladding layers or carriers that can be p-doped or n-doped Injection layer, as described above with respect to FIG. 7 .

The first reflector 724 and the second reflector 752 may each comprise pairs of dielectric layers, semiconductor layers, or metallic material layers (doped or undoped) having different refractive indices and/or thicknesses, such as GaAs and AlAs. (or AlGaAs) layer, oxide layer (for example, silicon oxide and another oxide layer) or the like). In some embodiments, at least one of the first reflector 724 or the second reflector 752 can include a high contrast grating (HCG), which can include a sub-wavelength grating layer made of a material having a large refractive index contrast. HCG can have a wide bandwidth with high reflectivity and can be used as a tunable mirror. The active region 726 may include, for example, an InGaAs quantum well layer and a GaAs barrier layer, an InAlGaAs quantum well layer and an AlGaAs barrier layer, or the like.

In the illustrated example, the tunable VCSEL 705 includes a micro-electro-mechanical-system (MEMS) device 762 in a tunable vertical cavity formed by a first reflector 724 and a second reflector, where the second Reflector 752 may be formed on MEMS device 762 and thus may be movable by MEMS device 762 . In some embodiments, other microactuators or nanoactuators (such as micromotors, piezoelectric actuators, ferroelectric actuators, magnetic actuators, ultrasonic actuators, or the like) can be used to move the second reflector 752 . Light emitted by VCSEL 722 and oscillating within the vertical cavity formed by first reflector 724 and second reflector 752 can be tuned by tuning the orientation of second reflector 752 using MEMS device 762 or another actuator to tune the optical path length and thus tune the resonant wavelength of the vertical cavity to be tuned continuously.

As described above, the spectral coverage of lasers based on III-V semiconductors (eg, InGaN or AlGaAs) can be limited by the properties of the available gain medium (eg, bandgap). It can be extremely difficult to manufacture VCSELs for some colors (eg, green) with high efficiency. Fabricating visible laser sources for multiple colors on the same chip or wafers can be even more challenging. Furthermore, current visible light sources may typically be of large size and thus may not be suitable for individually addressable high density arrays of visible light sources. The integration of III-V semiconductor devices with photonic integrated circuits (PICs) may present additional challenges to fabrication.

According to some embodiments, the nonlinear effect of certain nonlinear gain media can be used to generate visible light in a broad spectral range using IR pump light from a VCSEL. In one example, the visible semiconductor light source may include a VCSEL that can emit light in the near infrared (NIR) or other infrared (IR) bands with high efficiency. Visible semiconductor light sources can also include microresonators ^that include third-order nonlinear materials and thus can use degenerate Four-wave mixing, also known as third-order optical parametric oscillation (OPO), converts IR light into visible light.

Four-wave mixing is a nonlinear effect caused by third-order optical nonlinearity (Kerr effect) described by the χ ⁽³⁾ coefficient. Four-wave mixing can occur when light with two frequency components _v1 and _v2 co-propagates in an optical waveguide comprising a third-order nonlinear medium. Refractive index modulation due to third-order nonlinear effects can lead to the generation of light with two additional frequency components _ν3 and _ν4 , where _ν4 = _ν1 + _ν2 − _ν3 , with frequencies ν3 and ν4 Light can undergo parametric amplification in nonlinear media. This procedure may be called nondegenerate four-wave mixing. When two of the four frequency components ν ₁ and ν ₂ coincide, degenerate four-wave mixing (DFWM) can occur, where a single frequency pump wave (eg, with frequency ν _p ) can Cause the generation and amplification of signal wave (with frequency ν _s ) and idler wave (with frequency ν _i ), and the frequency-phase matching condition 2ν _p = ν _s +ν _i can be met. The signal wave and the idler wave can generally have different frequencies.

8A and 8B illustrate an example of generating a higher frequency optical signal via degenerate four - wave mixing using low frequency pump light. Two pump photons 810 with frequency _νp can be summed to produce a virtual excited state 815, which can be used to generate a pair of photons 820 and 830 with frequencies _νs and _νi , respectively. Due to conservation of energy, the frequencies _νs and _νi of the photons 820 and 830 can be symmetric about the frequency _νp of the pump photon 810 (i.e., | _{νs −νp} |=| _νp − _νi |), as Shown in Figure 8B.

Four-wave mixing is a phase-sensitive procedure. The effects of four-wave mixing can accumulate over longer distances (e.g. via many loops in a ring resonator) if the phase-matching conditions for constructive interference are met (which can be affected by dispersion and/or nonlinear phase shifts) ). A ring resonator may include a closed loop waveguide coupled to an input coupler and/or an output coupler. As light at the resonant wavelength of the ring resonator propagates through the closed loop waveguide, its intensity builds up over multiple round trips due to constructive interference between the loops. Only a few wavelengths of light can resonate within a closed loop waveguide. The optical path length of the ring resonator may be 2πr×n _eff , where r is the radius of the ring resonator and n _eff is the effective index of refraction of the ring resonator. In order to meet the resonance condition for constructive interference, the optical path length of the ring (loop) can be an integer multiple of the wavelength of the resonant light: m×λ _m =2πr×n _eff , where λ _m is the resonance wavelength and m is the ring resonance Modulus of the device (positive integer). The resonance frequency or wavelength can be tuned by changing the effective refractive index n _eff of the ring resonator and/or by changing the wavelength of the pump light.

。兩個鄰近模式之頻率之間的差為自由頻譜範圍

。微諧振器之品質因數Q及精細度F可藉由以下描述：

，及

其中λ為工作波長。品質因數可用於判定給定環諧振器之諧振條件之頻譜範圍，且亦適用於量化諧振器中往返損失之量。低Q因數可由較大損失造成。精細度F亦可與諧振器損失相關，且因此可指示往返諧振器損失。 Figure 8C illustrates multiple longitudinal resonant modes of an example of a microresonator (eg, a ring resonator). Figure 8C shows three longitudinal resonant modes m-1, m and m+1. The full-width half-magnitude (FWHM) of the transmission spectrum in the longitudinal mode is

. The difference between the frequencies of two adjacent modes is the free spectral range

. The quality factor Q and fineness F of a microresonator can be described by the following:

,and

Where λ is the working wavelength. The figure of merit can be used to determine the spectral extent of the resonance conditions for a given ring resonator, and is also useful for quantifying the amount of round trip losses in the resonator. A low Q-factor can be caused by large losses. Fineness F can also be related to resonator losses, and thus can be indicative of round-trip resonator losses.

OPO is optical parametric amplification (OPA) within an optical resonator (eg, a resonant optical cavity). For example, in a ring resonator, OPO is a cavity-enhanced DFWM, where all three light waves (pump, signal, and idler waves) meet the resonance conditions of the same cavity, and thus can resonate in the ring resonator To greatly enhance nonlinear conversion via resonance-enhanced field strength accumulation. Thus, the frequency of the pump wave can be limited to a set of longitudinal resonant modes determined by the optical path length of the ring resonator at the pump wavelength. Similarly, the frequency of the signal wave can be limited to a set of longitudinally resonant modes determined by the optical path length of the ring resonator at the signal wavelength, and the frequency of the idler wave can be limited to the optical path length by the ring resonator at the idler wavelength. A set of longitudinal resonant modes for path length determination. Using low-loss optical resonators (e.g., ring resonators), nonlinear conversion efficiency can be significantly improved within resonators with tight footprints (e.g., <10 μm radius for some high-index materials such as SiC) (>10%). Resonant optical cavities (eg, ring resonators) can be designed to generate light of any color in the visible range, since the wavelength (color) of the generated signal wave can be controlled by the optical path length of the cavity to meet the resonance conditions.

According to some embodiments, the pump light for DFWM in a resonant optical cavity (e.g., a microresonator) can be IR light generated by a VCSEL, where the microresonator can be positioned in an intracavity configuration or an extracavity configuration, respectively. inside or outside the VCSEL cavity. The IR light emitted by the VCSEL can be coupled into the microresonator directly or through a coupling structure (eg, a grating coupler). In some embodiments, IR light emitted by a VCSEL can be coupled into a waveguide by a coupling structure inside or outside the VCSEL cavity (e.g., a grating coupler or a nanoresonator) and can then be coupled from the waveguide into a microresonator . In some embodiments, grating couplers can include apodized, chirped, and/or tilted gratings to achieve desired coupling directions and desired coupling efficiencies. In some embodiments, a visible light source can include multiple coupling structures in extracavity or intracavity configurations.

Microresonators can include low-loss structures where light can travel for long periods of time before being absorbed, scattered, or converted. As described above, the color of light produced by the OPO process can be controlled by the geometry and material (and thus effective refractive index) of the microresonator. According to some embodiments, microresonators may include, for example, microring resonators as described above, photonic crystal point defect cavities, photonic crystal ring (line defect) cavities, plasmonic resonators, waveguide grating based resonators, or its analogues. For example, when a point defect is created in a photonic crystal, the defect can pull the optical mode into the bandgap and trap the optical mode (forming a resonant cavity), since this state is prohibited from propagating in the bulk crystal, and in the resonant The density of states at frequency can be extremely high in the resonator to achieve high efficiency. Photonic crystal line defect cavities can be formed by, for example, omitting multiple holes in a photonic crystal slab.

According to some embodiments, visible light generated by degenerate four-wave mixing in the cavity of the microresonator can be coupled out of the microresonator into the waveguide of the PIC via edge coupling, or can be coupled via a coupling structure such as a grating coupler. The vertical coupling couples out of the microresonator into free space. In some embodiments, grating couplers can include apodized, chirped, and/or tilted gratings to achieve desired coupling directions and high coupling efficiencies.

9A shows a cross-sectional view of an example of a structure 900 including a coupling structure 920 configured to couple light generated in an optical resonator 910 out of the optical resonator 910 vertically, according to certain embodiments. Figure 9B shows a top view of an example of the structure 900 of Figure 9A, according to certain embodiments. In the illustrated example, optical resonator 910 may comprise a microring resonator. In some embodiments, optical resonator 910 may have a shape other than a ring shape, such as an elliptical shape, an orbital shape, a spiral shape (eg, an Archimedean spiral shape), or another closed loop. Optical resonator 910 may include low loss materials with third order nonlinearity. In some embodiments, to reduce the footprint of the optical resonator 910, the optical resonator 910 may include a high refractive index material, such as SiN or SiC. The coupling structure 920 may include a grating coupler formed on the optical resonator 910, wherein the grating coupler may be along the inner circumference of the optical resonator 910, on the top or bottom of the optical resonator 910, along the outer circumference of the optical resonator 910 or any combination of the preceding positions. The grating coupler may include a tilted grating having a grating vector that includes a component in the z-direction such that light propagating in a ring in the xy plane in the optical resonator 910 can be coupled out of the optics vertically by the grating coupler. Resonator 910.

9C illustrates a top view of an example of a structure 902 configured to couple light generated in an optical resonator 930 into an output waveguide 950 , according to certain embodiments. In the example shown in FIG. 9C , IR pump light from the VCSEL can be coupled from pump waveguide 940 into optical resonator 930 and the resulting visible light (eg, signal wave) can be coupled into output waveguide 950 . The idler wave can be coupled into the pump waveguide 940 or the output waveguide 950 . In some embodiments, a wavelength division demultiplexer may be used to separate the signal wave from the idler wave.

9D illustrates a top view of an example of a structure 904 configured to couple light generated in an optical resonator into a waveguide 980 , according to certain embodiments. In the illustrated example, IR pump light from the VCSEL can be coupled at least partially from waveguide 980 into optical resonator 960 , and the resulting visible light (eg, a signal wave) can be coupled back into waveguide 980 . The idler wave may be coupled into waveguide 980 or another waveguide 970 . In some embodiments, a wavelength division demultiplexer may be used to separate the signal wave and the uncoupled pump wave in waveguide 980 . In some embodiments, uncoupled pump waves can be recycled back into waveguide 980 and coupled into optical resonator 960 .

10A illustrates an example of a visible light source 1000 including a microresonator 1040 in a vertical cavity and directly pumped by an infrared light VCSEL 1020 in the vertical cavity, wherein visible light to be generated in the microresonator 1040, according to certain embodiments. Vertically coupled out of the vertical cavity. FIG. 10B illustrates a top view of an example of the visible light source 1000 of FIG. 10A. The vertical cavity in the visible light source 1000 can be formed by the first reflector 1022 and the second reflector 1050, where the first reflector 1022 and the second reflector 1050 can have high reflectivity (e.g., >80%, >85% for IR light) %, >90%, >95%, >99% or higher), and the second reflector 1050 may have low reflectivity or may be anti-reflective for visible light.

The visible light source 1000 can include a driver circuit 1010 that can be bonded to the VCSEL directly or indirectly (eg, via an interposer or thin film transistor layer) by, for example, die-to-wafer bonding or wafer-to-wafer bonding. 1020. The driver circuit 1010 may include various circuits formed on a silicon substrate, as described above, for example, with respect to FIG. 6 . The driver circuit 1010 may be coupled to the electrodes of the VCSEL 1020 to drive the VCSEL 1020 to generate continuous wave (CW) or pulsed IR light of sufficiently long duration. The intensity of the IR light emitted by VCSEL 1020 and thus the intensity of visible light from visible light source 1000 can be controlled by the drive current or voltage supplied to VCSEL 1020 by drive circuit 1010 .

The VCSEL 1020 may include a first electrode 1030 (eg, an anode or a cathode), a second electrode 1032 , and a semiconductor structure (eg, an epitaxial layer) formed between the first electrode 1030 and the second electrode 1032 . The semiconductor structure can include, for example, a first reflector 1022, an active region 1024 that can emit IR light, and other semiconductor layers (not labeled in FIG. 10A ), such as cladding layers or carrier layers that can be p-doped or n-doped. Injection layer, as described above with respect to FIG. 7 . The first reflector 1022 may comprise, for example, a high-contrast grating (HCG) as described with respect to FIG. undoped) (such as GaAs and AlAs (or AlGaAs) layers, oxide layers (eg, silicon oxide and another oxide layer) or the like). The active region 1024 may include, for example, an InGaAs quantum well layer and a GaAs barrier layer, an InAlGaAs quantum well layer and an AlGaAs barrier layer, or the like.

In some embodiments, the VCSEL 1020 can include a partial reflector 1026 for the IR light, wherein the partial reflector can partially reflect and partially transmit the IR light emitted in the active region 1024 to form the VCSEL 1020 with the first reflector 1022 the resonant cavity. The resonant cavity formed by partial reflector 1026 and first reflector 1022 can help narrow and select the output wavelength range of IR light and improve the gain and intensity of emitted IR light. In some embodiments, VCSEL 1020 may include polarizer 1028 . Polarizer 1028 can be used to control the polarization state of IR light emitted by VCSEL 1020 and improve the coupling efficiency of IR light into microresonator 1040 by, for example, a grating coupler or a nanoresonator (e.g., metastructure), which can is polarization dependent. In some embodiments, other polarization components such as waveplates, spatially varying polarizers, or spatially varying waveplates may be used instead to control the polarization state of the IR light emitted by VCSEL 1020 .

The IR light emitted by the VCSEL 1020 can be coupled into the microresonator 1040 directly or via a coupling structure such as a tilted grating or a nanoresonator. As described above, the microresonator 1040 may comprise a closed loop waveguide having any suitable shape (e.g., a ring, ellipse, helix, or orbital shape) with low loss such that photons can be absorbed, scattered, Or propagate in a closed loop waveguide for a longer period of time (eg, about a thousand or more loops) before switching. The waveguide material can have a third order nonlinearity such that OPO (eg, DFWM) procedures can occur in closed loop waveguides. The materials and geometry of the microresonator 1040 can be selected such that IR light coupled into the microresonator 1040 and visible light (signal wave) and idler waves generated by the DFWM procedure can resonate in the microresonator 1040, whereby The DFWM program can be enhanced. In some embodiments, the microresonator 1040 can include a material with a high refractive index such that the physical size of the microresonator 1040 can be reduced while achieving the desired optical path length of the closed loop waveguide. VCSEL 1020 and microresonator 1040 may be surrounded by a dielectric material 1060, which may include, for example, an oxide such as silicon dioxide, or a polymer material. In some embodiments, visible light source 1000 can include two or more microresonators arranged vertically and configured to generate visible light of the same color.

Visible light generated by the DFWM procedure in microresonator 1040 can be coupled out of microresonator 1040 vertically by coupling structure 1042, which can include a grating or nanoresonator as described above, for example, with respect to FIGS. 9A and 9B. device. Visible light coupled out of the microresonator 1040 can be transmitted with little or no loss by the second reflector 1050 because the second reflector 1050 can be antireflective for visible light, as described above. Like the first reflector 1022, the second reflector 1050 may comprise, for example, HCG, or a DBR structure formed of multiple layers of dielectric, semiconductor or metallic material with alternating refractive indices. The thickness and index of refraction of the dielectric layer, semiconductor layer, or metallic material layer in the DBR structure can be selected such that IR light reflected at adjacent interfaces between different materials can constructively interfere to enlarge the second reflector 1050 With respect to the total reflectivity of IR light, visible light reflected at adjacent interfaces between different materials at the same time can destructively interfere to reduce the total reflectivity of the second reflector 1050 for visible light. Thus, IR light emitted by VCSEL 1020 and not coupled into microresonator 1040 may be reflected back to microresonator 1040 by second reflector 1050 and/or first reflector 1022 and may be at least partially coupled into microresonator 1040. 1040 to improve the efficiency of IR light coupling into the microresonator 1040 and thus improve the efficiency of the visible light source 1000 . Microresonator 1040 , coupling structure 1042 and second reflector 1050 may be formed before or after bonding VCSEL 1020 to driver circuit 1010 .

11A illustrates an example of a visible light source 1100 including a microresonator 1150 outside the vertical cavity and directly pumped by an infrared light VCSEL 1120, according to certain embodiments. 11B illustrates a top view of an example of the visible light source 1100 of FIG . 11A. Visible light source 1100 may include driver circuitry 1110 that may be bonded to the VCSEL directly or indirectly (eg, via an interposer or thin film transistor layer) by, for example, die-to-wafer bonding or wafer-to-wafer bonding. 1120. Driver circuit 1110 may include various circuits formed on a silicon substrate, as described above, for example, with respect to FIG. 6 . Driver circuit 1110 may be coupled to the electrodes of VCSEL 1120 to drive VCSEL 1120 to generate continuous wave (CW) or pulsed IR light of sufficiently long duration and desired intensity. The intensity of the IR light emitted by VCSEL 1120 and thus the intensity of visible light from visible light source 1100 can be controlled by the drive current or voltage supplied to VCSEL 1120 by drive circuit 1110 .

The VCSEL 1120 may include a first electrode 1140 (eg, an anode or a cathode), a second electrode 1142 , and a semiconductor structure (eg, an epitaxial layer) formed between the first electrode 1140 and the second electrode 1142 . The semiconductor structure can include, for example, a first reflector 1122, an active region 1124 that can emit IR light, and other semiconductor layers (not labeled in FIG. 11A ), such as cladding layers or carrier layers that can be p-doped or n-doped. Injection layer, as described above with respect to FIG. 7 . The first reflector 1122 may include, for example, HCG, or be made of pairs of dielectric, semiconductor, or metallic material layers (doped or undoped) (such as GaAs and AlAs (or AlGaAs) layers having different refractive indices and thicknesses. , an oxide layer (eg, silicon oxide and another oxide layer) or the like). The first reflector 1122 may have a high reflectivity (eg, >80%, >85%, >90%, >95%, >99% or higher) for IR light. The active region 1124 may include, for example, an InGaAs quantum well layer and a GaAs barrier layer, an InAlGaAs quantum well layer and an AlGaAs barrier layer, or the like. VCSEL 1120 may also include second reflector 1130, which may be a partial reflector configured to reflect a portion of the IR light emitted by active region 1124 while transmitting the IR light emitted by active region 1124. Part of the IR light. The second reflector 1130 may include, for example, HCG, or a DBR structure formed of a conductive material such as GaAs and AlAs (or AlGaAs). The first reflector 1122 and the second reflector 1130 may form a vertical cavity in the visible light source 1100 . The vertical cavity can help narrow and select the output wavelength range of IR light and improve the gain and intensity of emitted IR light. In some embodiments, VCSEL 1120 can include a polarizer (not shown in Figure 11A), as described above with respect to Figure 10A. A polarizer can be used to control the polarization mode of the IR light emitted by the VCSEL 1120 and improve the coupling efficiency of IR light into the microresonator 1150 by, for example, a grating coupler or a nanoresonator (e.g., a metastructure), which can be Polarization dependent.

The IR light emitted by the VCSEL 1120 can be coupled into the microresonator 1150 directly or via a coupling structure such as a tilted grating or a nanoresonator. As described above, the microresonator 1150 may comprise a closed loop waveguide having any suitable shape (e.g., ring, ellipse, helical, or orbital shape) with low loss such that photons can be absorbed, scattered, Or propagate in a closed loop waveguide for a long period of time (eg, about a thousand or more loops) before switching. The waveguide material can have a third order nonlinearity such that OPO (eg, DFWM) procedures can occur in closed loop waveguides. The size and material of the microresonator 1150 can be selected such that IR light coupled into the microresonator 1150 and visible light (signal wave) and idler waves generated by the DFWM procedure can resonate in the microresonator 1150, which can Enhanced DFWM program. In some embodiments, the microresonator 1150 can include a material with a high refractive index (eg, SiN, SiC, etc.) so that the physical size of the microresonator 1150 can be reduced while achieving the desired optical path length of the closed loop waveguide. VCSEL 1120 and microresonator 1150 may be surrounded by a dielectric material 1160, which may include, for example, an oxide such as silicon dioxide.

Visible light generated by the DFWM procedure in microresonator 1150 can be coupled out of microresonator 1150 vertically by coupling structure 1152, which can include a grating or nanoresonator as described above, for example, with respect to FIGS. 9A and 9B. device. Visible light coupled out of microresonator 1150 may be coupled out of visible light source 1100 vertically. Microresonator 1150 and coupling structure 1152 may be formed before or after bonding VCSEL 1120 to driver circuit 1110 . In some embodiments, visible light generated in microresonator 1150 can be coupled to a waveguide, as described with respect to Figures 9C and 9D.

In some embodiments, a feedback cavity structure (DBR structure or a thermal mirror that reflects IR light and transmits visible light) can be formed on top of microresonator 1150 and coupling structure 1152 to recouple IR light that has not been coupled into microresonator 1150. Redirected back to microresonator 1150 to improve the efficiency of coupling the IR pump light into microresonator 1150 and the efficiency of visible light source 1100 .

12A illustrates an example of a visible light source 1200 including a microresonator 1260 pumped by an infrared light VCSEL 1220, wherein the infrared light is coupled to in the microresonator. 12B illustrates a top view of an example of the visible light source 1200 of FIG . 12A. Visible light source 1200 may include driver circuitry 1210 that may be bonded to the VCSEL directly or indirectly (eg, via an interposer or thin film transistor layer) by, for example, die-to-wafer bonding or wafer-to-wafer bonding. 1220. Driver circuit 1210 may include various circuits formed on a silicon substrate, as described above, for example, with respect to FIG. 6 . Driver circuit 1210 may be coupled to the electrodes of VCSEL 1220 to drive VCSEL 1220 to generate continuous wave (CW) or pulsed IR light of sufficiently long duration and desired intensity. The intensity of the IR light emitted by VCSEL 1220 and thus the intensity of visible light from visible light source 1200 can be controlled by the drive current or voltage supplied to VCSEL 1220 by drive circuit 1210 .

VCSEL 1220 may be similar to VCSEL 1120 and may include a first electrode 1240 (eg, anode or cathode), a second electrode 1242, and a semiconductor structure (eg, an epitaxial layer) formed between first electrode 1240 and second electrode 1242 . ). The semiconductor structure can include, for example, a first reflector 1222, an active region 1224 that can emit IR light, and other semiconductor layers (not labeled in FIG. 12A ), such as cladding layers or carrier layers that can be p-doped or n-doped. Injection layer, as described above with respect to FIG. 7 . The first reflector 1222 may comprise, for example, HCG, or be composed of pairs of dielectric or doped or undoped semiconductor materials (such as GaAs and AlAs (or AlGaAs) layers, oxide layers (such as , silicon oxide and another oxide layer) or the like) to form a DBR reflector. The first reflector 1222 may have a high reflectivity (eg, >80%, >85%, >90%, >95%, >99% or higher) for IR light. The active region 1224 may include, for example, an InGaAs quantum well layer and a GaAs barrier layer, an InAlGaAs quantum well layer and an AlGaAs barrier layer, or the like. The VCSEL 1220 may also include a second reflector 1230, which may be a partial reflector configured to reflect a portion of the IR light emitted by the active region 1224 while transmitting the IR light emitted by the active region 1224. Part of the IR light. The second reflector 1230 may comprise, for example, HCG, or a DBR structure formed from a conductive material such as doped or undoped GaAs and AlAs (or AlGaAs). The first reflector 1222 and the second reflector 1230 may form a vertical cavity in the visible light source 1200 . The vertical cavity can help select the output wavelength range of IR light and improve the gain and intensity of the emitted IR light. In some embodiments, VCSEL 1220 can include polarizing elements (eg, polarizers, waveplates, spatially varying polarizers, or spatially varying waveplates, not shown in FIG. 12A ), as described above with respect to FIG. 10A . A polarizer can be used to control the polarization mode of the IR light emitted by the VCSEL 1220 and improve the coupling efficiency of the IR light into the microresonator 1260 by, for example, a grating coupler or a nanoresonator (e.g., a metastructure), which can be Polarization dependent.

IR light emitted by the VCSEL 1220 may be coupled into the waveguide 1250 directly or via a coupling structure 1252 (which may be above or below the waveguide 1250), such as a tilted grating or a nanoresonator. IR light propagating in waveguide 1250 may be coupled into microresonator 1260 . In the illustrated example, waveguide 1250 and microresonator 1260 may be on the same waveguide material layer (eg, SiN or SiC layer). As described above, the microresonator 1260 may comprise a closed loop waveguide having any suitable shape (e.g., ring, ellipse, helical, or orbital shape) with low loss such that photons can be absorbed, scattered, Or propagate in a closed loop waveguide for a long period of time (eg, about a thousand or more loops) before switching. The waveguide material can have a third order nonlinearity such that OPO (eg, DFWM) procedures can occur in closed loop waveguides. The geometry and materials of the microresonator 1260 can be selected such that IR light coupled into the microresonator 1260 and visible light (signal wave) and idler waves generated by the DFWM procedure can resonate in the microresonator 1260, thus The DFWM program can be enhanced. In some embodiments, microresonator 1260 can include a material with a high refractive index (eg, SiN, SiC, etc.), so that the physical size of microresonator 1260 can be reduced while achieving the desired optical path length of the closed loop waveguide. VCSEL 1220, waveguide 1250, and microresonator 1260 may be surrounded by a dielectric material 1270, which may include, for example, an oxide such as silicon dioxide.

In some embodiments, visible light generated by the DFWM process in microresonator 1260 can be vertically coupled out of microresonator 1260 through a coupling structure, such as a grating or nanoresonator as described above. Visible light coupled out of microresonator 1260 may be coupled vertically out of visible light source 1200 into free space. In some embodiments, visible light generated in microresonator 1260 can be coupled to a waveguide (e.g., waveguide 1250 or another waveguide closely coupled to microresonator 1260) and a photonic integrated circuit, as with respect to FIGS. 9C and 9D Described.

In some embodiments, feedback cavity structures (DBR structures or thermal mirrors that reflect IR light and transmit visible light) can be formed on top of waveguide 1250 and coupling structure 1252 to redirect IR light that has not been coupled into waveguide 1250 back into waveguide 1250 to improve the efficiency of coupling the IR pump light into the waveguide 1250 and the efficiency of the visible light source 1200.

12C illustrates an example of a visible light source 1202 including a microresonator 1262 pumped by an infrared light VCSEL 1220 through a coupling structure 1252 and a waveguide 1250 on a different vertical layer than the microresonator 1262 , according to some embodiments. Coupled into the microresonator 1262. Figure 12D illustrates a top view of an example of the visible light source 1202 of Figure 12C. Visible light source 1202 may be similar to visible light source 1200, but may differ in that, for example, in visible light source 1202, microresonator 1262 and waveguide 1250 are on different waveguide layers. In the illustrated example, microresonator 1262 may be above waveguide 1250 . In some embodiments, microresonator 1262 may be below waveguide 1250 . Although not shown in FIGS. 12C and 12D , visible light source 1202 may include a coupling structure (e.g., a grating or nanoresonator) configured to vertically couple visible light generated in microresonator 1262 out of microresonator 1262, Or a waveguide closely coupled to the microresonator 1262 and configured to couple visible light generated in the microresonator 1262 into a photonic integrated circuit may be included.

13A illustrates yet another example of a visible light source 1300 including a microresonator 1370 pumped by an infrared light VCSEL 1320 in a vertical cavity through an in-coupling structure 1352 in the vertical cavity and with the microresonator, according to certain embodiments. Resonator 1370 is coupled into microresonator 1370 on the same vertical layer as waveguide 1350 . Figure 13B illustrates a top view of an example of the visible light source 1300 of Figure 13A. The vertical cavity in visible light source 1300 can be formed by first reflector 1322 and second reflector 1330, where first reflector 1322 and second reflector 1330 can have high reflectivity (e.g., >80%, >85% for IR light) %, >90%, >95%, >99% or higher).

Visible light source 1300 may include driver circuitry 1310, which may be bonded to the VCSEL directly or indirectly (eg, via an interposer or thin film transistor layer) by, for example, die-to-wafer bonding or wafer-to-wafer bonding. 1320. Driver circuit 1310 may include various circuits formed on a silicon substrate, as described above, for example, with respect to FIG. 6 . Driver circuit 1310 may be coupled to the electrodes of VCSEL 1320 to drive VCSEL 1320 to generate continuous wave (CW) or pulsed IR light of sufficiently long duration and desired intensity. The intensity of the IR light emitted by VCSEL 1320 and thus the intensity of visible light from visible light source 1300 can be controlled by the drive current or voltage supplied to VCSEL 1320 by drive circuit 1310 .

The VCSEL 1320 may include a first electrode 1340 (eg, an anode or a cathode), a second electrode 1342 , and a semiconductor structure (eg, an epitaxial layer) formed between the first electrode 1340 and the second electrode 1342 . The semiconductor structure can include, for example, a first reflector 1322, an active region 1324 that can emit IR light, and other semiconductor layers (not labeled in FIG. 13A ), such as cladding layers or carrier layers that can be p-doped or n-doped. Injection layer, as described above with respect to FIG. 7 . The first reflector 1322 may include, for example, HCG, or be made of pairs of dielectric, semiconductor, or metallic material layers (doped or undoped) (such as GaAs and AlAs (or AlGaAs) layers having different refractive indices and thicknesses. , an oxide layer (eg, silicon oxide and another oxide layer) or the like). The active region 1324 may include, for example, an InGaAs quantum well layer and a GaAs barrier layer, an InAlGaAs quantum well layer and an AlGaAs barrier layer, or the like.

In some embodiments, the VCSEL 1320 can include a partial reflector 1326 for the IR light, wherein the partial reflector can partially reflect and partially transmit the IR light emitted in the active region 1324 to form the VCSEL 1320 with the first reflector 1322 the resonant cavity. The resonant cavity formed by partial reflector 1326 and first reflector 1322 can help narrow and select the output wavelength range of IR light and improve the gain and intensity of emitted IR light. In some embodiments, VCSEL 1320 may include polarizer 1328 . Polarizer 1328 can be used to control the polarization mode of the IR light emitted by VCSEL 1320 and improve the coupling efficiency of IR light into waveguide 1350 by input coupling structure 1352 (e.g., a grating coupler or nanoresonator), which can be polarized Dependent. In some embodiments, other polarization components such as waveplates, spatially varying polarizers, or spatially varying waveplates may be used instead to control the polarization state of the IR light emitted by VCSEL 1320 .

IR light emitted by the VCSEL 1320 can be coupled into the waveguide 1350 by an incoupling structure 1352 such as a tilted grating or nanoresonator (eg, metastructure). IR light propagating in waveguide 1350 may be coupled into microresonator 1370 . In the illustrated example, waveguide 1350 and microresonator 1370 may be on the same waveguide material layer (eg, SiN or SiC layer). As described above, the microresonator 1370 may comprise a closed loop waveguide having any suitable shape (e.g., ring, ellipse, helical, or orbital shape) with low loss such that photons can be absorbed, scattered, Or propagate in a closed loop waveguide for a longer period of time (eg, about 1 million loops or more) before switching. The waveguide material can have a third order nonlinearity such that OPO (eg, DFWM) procedures can occur in closed loop waveguides. The size and material of the microresonator 1370 can be selected such that IR light coupled into the microresonator 1370 and visible light (signal wave) and idler waves generated by the DFWM process can resonate in the microresonator 1370, which can Enhanced DFWM program. In some embodiments, microresonator 1370 can include a material with a high refractive index (e.g., SiN, SiC, or the like), so that the physical size of microresonator 1370 can be reduced while still achieving the desired closed loop waveguide. Optical path length. VCSEL 1320, waveguide 1350, and microresonator 1370 may be surrounded by a dielectric material 1360, which may include, for example, an oxide such as silicon dioxide.

In some embodiments, visible light generated by the DFWM process in microresonator 1370 can be vertically coupled out of microresonator 1370 through a coupling structure, such as a grating or nanoresonator as described above. Visible light coupled out of microresonator 1370 may be coupled out of visible light source 1300 vertically. In some embodiments, visible light generated in microresonator 1370 can be coupled to a waveguide (e.g., waveguide 1350 or another waveguide closely coupled to microresonator 1370) and a photonic integrated circuit, as with respect to FIGS. 9C and 9D Described.

Like the first reflector 1322, the second reflector 1330 may include, for example, HCG, or a DBR structure formed of multiple layers of dielectric, semiconductor, or metallic material with alternating refractive indices. The thickness and index of refraction of the dielectric, semiconductor, or metallic material layers in the DBR structure can be selected such that IR light reflected at adjacent interfaces between different materials can constructively interfere to enlarge the second reflector 1330 Total reflectance for IR light. Accordingly, IR light emitted by the VCSEL 1320 and not yet coupled into the waveguide 1350 may be reflected back to the waveguide 1350 by the second reflector 1330 and/or the first reflector 1322, and may be at least partially coupled into the waveguide 1350 to improve The efficiency of coupling IR pump light into the microresonator 1370 and the efficiency of the visible light source 1300.

13C illustrates an example of a visible light source 1302 including a microresonator 1372 pumped by an infrared VCSEL 1320 through an in-coupling structure 1352 in a vertical cavity and with a microresonator 1372 in accordance with certain embodiments. The waveguides 1350 on different vertical layers of the microresonator 1372 are coupled into the microresonator 1372 . Figure 13D illustrates a top view of an example of the visible light source 1302 of Figure 13C. Visible light source 1302 may be similar to visible light source 1300, but may differ in that, for example, in visible light source 1302, microresonator 1372 and waveguide 1350 are located on different waveguide layers. In the illustrated example, microresonator 1372 may be above waveguide 1350 . In some embodiments, microresonator 1372 may be below waveguide 1350 . Although not shown in FIGS. 13C and 13D , visible light source 1302 may include a coupling structure (e.g., a grating or nanoresonator) configured to vertically couple visible light generated in microresonator 1372 out of microresonator 1372, Or a waveguide closely coupled to the microresonator 1372 and configured to couple visible light generated in the microresonator 1372 into the photonic integrated circuit may be included.

In a color image display system, it may be necessary to integrate visible light sources for multiple colors on the same chip. To improve the resolution of the displayed image, it may also be desirable to use a high density source array with a large number of individually addressable light sources. Current visible light sources can typically have large footprints and may not be suitable for high density source arrays with individually addressable light sources. The VCSEL pumped visible light sources described above can be used to fabricate high density source arrays including individually addressable light sources for different colors of visible light.

According to some embodiments, the device can include an array of visible light sources, wherein the visible light sources can emit visible light of different colors, such as red, blue, or green. In one example, each visible light source may include a microresonator, and the microresonators (and/or VCSELs) in some visible light sources may be different from the microresonators (and/or VCSELs) in some other visible light sources, The visible light source can emit light of different colors. In some embodiments, each visible light source in the array of visible light sources can be configured or tuned to emit light of a different color. For example, each visible light source can include a pumped VCSEL and multiple microresonators with different parameters, where each of the multiple microresonators can be configured to generate visible light of a different distinct color, and at some In a specific example, each of the plurality of microresonators can be tuned to adjust the intensity of visible light generated by the microresonator. In some embodiments, a visible light source can include: a tunable pump VCSEL (with a tunable cavity) that can be tuned to emit pump light with different wavelengths; and a microresonator that can have multiple resonant modes and Visible light of different colors can be generated using pump light with different wavelengths.

14A illustrates an example of an array 1400 of visible light sources configured to emit different colors of visible light, where each visible light source in the array is included in a vertical cavity and is directly pumped by an infrared light VCSEL in the vertical cavity, according to certain embodiments. The microresonator, and the visible light generated in the microresonator is vertically coupled out of the vertical cavity. FIG. 14A shows red light source 1406 , green light source 1404 , and blue light source 1402 in visible light source array 1400 . Each light source shown in Figure 14A can be an example of visible light source 1000 or 1100, and the visible light sources in an array of visible light sources can be fabricated on the same wafer or on the same die. The wafer or die may be bonded directly or indirectly (eg, via an interposer or thin film transistor layer) to drive circuitry 1410 , such as a CMOS backplane, using various wafer-to-wafer bonding techniques or die-to-wafer bonding techniques.

Each light source 1402, 1404 or 1406 may include a VCSEL 1420 that emits IR light. As described above with respect to, eg, FIGS. 10 and 11 , the VCSEL 1420 may include a first electrode 1430 (eg, an anode or a cathode), a second electrode 1432, and a semiconductor structure formed between the first electrode 1430 and the second electrode 1432 ( For example, epitaxial layers). The semiconductor structure can include, for example, a first reflector 1422, an active region 1424 that can emit IR light, and other semiconductor layers (not labeled in FIG. 14A ), such as cladding layers or carrier layers that can be p-doped or n-doped. Injection layer, as described above with respect to FIG. 7 . The first reflector 1422 may include, for example, HCG, or be made of pairs of dielectric, semiconductor, or metallic material layers (doped or undoped) (such as GaAs and AlAs (or AlGaAs) layers having different refractive indices and thicknesses. , an oxide layer (eg, silicon oxide and another oxide layer) or the like). The active region 1424 may include, for example, an InGaAs quantum well layer and a GaAs barrier layer, an InAlGaAs quantum well layer and an AlGaAs barrier layer, or the like. VCSELs 1420 in light sources 1402, 1404, and 1406 may have the same structure and may emit IR light at about the same wavelength. In some embodiments, VCSEL 1420 can include a partial reflector for IR light (such as partial reflector 1026, not shown in FIG. 14A ), where the partial reflector can partially reflect and partially transmit light emitted in active region 1424. The IR light forms a resonant cavity of the VCSEL 1420 with the first reflector 1422 . The resonant cavity formed by the partial reflector and the first reflector 1422 can help narrow and select the output wavelength range of the IR light emitted by the VCSEL 1420 and improve the gain and intensity of the emitted IR light. In some embodiments, VCSEL 1420 may include a polarizer (not shown in FIG. 14A ), such as polarizer 1028 . A polarizer can be used to control the polarization mode of the IR light emitted by the VCSEL 1420 and improve the coupling efficiency of the IR light into the microresonator by, for example, a grating coupler or a nanoresonator (e.g., metastructure), which can be polarized Dependent.

In the illustrated example, each light source 1402, 1404, or 1406 can include a microresonator, wherein the microresonator of each light source 1402, 1404, or 1406 can have a different respective design and thus can generate different wavelengths of visible light. Different individual designs may include, for example, different combinations of loop shapes (eg, loops, ellipses, spirals, orbits, etc.), dimensions, materials (and thus refractive indices), and the like. For example, the red light source 1406 can include a microresonator 1444 whose shape, size, and material can be selected such that red light can be radiated by DFWM using IR light emitted by the VCSEL 1420 as pump light in the microresonator 1444. generated in resonator 1444. Red light source 1406 may also include coupling structure 1454 configured to vertically couple red light generated in microresonator 1444 out of microresonator 1444 . Similarly, the green light source 1404 can include a microresonator 1442 configured such that green light can be generated in the microresonator 1442 by DFWM using IR light emitted by the VCSEL 1420 as pump light, and can A coupling structure 1452 is included that is configured to vertically couple green light generated in the microresonator 1442 out of the microresonator 1442 . The blue light source 1402 may include a microresonator 1440 configured such that blue light may be generated in the microresonator 1440 by DFWM using IR light emitted by the VCSEL 1420 as pump light, and may include coupling Structure 1450 configured to vertically couple blue light generated in microresonator 1440 out of microresonator 1440 .

As illustrated, each light source 1402, 1404, or 1406 may also include a second reflector 1460, 1462, or 1464 configured to be emitted by the VCSEL 1420 but not yet coupled into the microresonator The IR light is reflected back to the microresonator or to a coupling structure used to couple the IR light into the microresonator. The second reflector 1460, 1462 or 1464 may have nearly 100% reflectivity for the IR light emitted by the VCSEL 1420, and may have a reflectivity for the visible light generated in the corresponding microresonator and coupled out of the corresponding microresonator by the corresponding coupling structure. Close to 0% reflectance. For example, second reflector 1460 can be antireflective for blue light, second reflector 1462 can be antireflective for green light, and second reflector 1464 can be antireflective for red light.

14B and 14C illustrate top views of an example of an array 1400 of visible light sources . An example of a visible light source array 1400 shown in FIGS. 14B and 14C can be used as an active display panel or as a light source for a backlight unit of a liquid crystal display such as a liquid crystal on silicon (LCOS) display. In the illustrated example, red light sources 1406 may be grouped in some rows, green light sources 1404 may be grouped in some other rows, and blue light sources 1402 may be grouped in some other rows, where rows of light sources of different colors Can be interleaved. In some embodiments, light sources 1402, 1404, and 1406 may be configured in other ways. For example, the visible light source array may include pixel units arranged in a two-dimensional array, wherein each pixel unit may include a red light source 1406 , a green light source 1404 and a blue light source 1402 arranged on vertices of a triangle. Light sources of different colors in a light source array can be fabricated on the same wafer or on the same die using the same process, rather than being fabricated separately and then picked and placed on a CMOS substrate. The spacing between visible light source array 1400 and the size of each light source can be selected based on the application. In some embodiments, the diameter of each light source can be less than about 50 μm, less than about 30 μm, less than about 20 μm, or less than about 10 μm. The distance between the visible light source array 1400 may also be less than about 50 μm, less than about 30 μm, less than about 20 μm, or less than about 10 μm.

15A and 15B illustrate an example of an array of visible light sources 1500 in which each visible light source 1502 can emit visible light in multiple colors , according to certain embodiments. Each visible light source 1502 in the visible light source array 1500 includes a plurality of microresonators positioned in a vertical cavity formed by the first reflector 1522 and the second reflector 1530, wherein the plurality of microresonators are controlled by the same microresonator in the vertical cavity. The IR emitting VCSEL 1520 is pumped to generate visible light of different colors. The first reflector 1522 and the second reflector 1530 may have high reflectivity (eg, >80%, >85%, >90%, >95%, >99% or higher) for IR light. In some embodiments, the first reflector 1522 can have a high reflectivity (eg, >80%, >85%, >90%, >95%, >99%, or higher) for visible light. The second reflector 1530 may be anti-reflection for visible light. Visible light of different colors generated in the microresonator is vertically coupled out of the microresonator by the respective coupling structures and can be transmitted out of the vertical cavity through the second reflector 1530 .

As illustrated, visible light source 1502 may include driver circuitry 1510 formed on a CMOS backplane, where the CMOS backplane may be bonded directly or indirectly (e.g., via an interposer or thin film transistor layer) to VCSELs 1520 including VCSELs fabricated thereon. of wafers. The plurality of microresonators and the second reflector 1530 can be formed before or after bonding the wafer including the VCSEL 1520 to the CMOS backplane. The VCSEL 1520 may include a first electrode 1540 (eg, an anode or a cathode), a second electrode 1542 , and a semiconductor structure (eg, an epitaxial layer) formed between the first electrode 1540 and the second electrode 1542 . The semiconductor structure can include, for example, a first reflector 1522, an active region 1524 that can emit IR light, and other semiconductor layers (not labeled in FIG. 15A ), such as cladding layers or carrier layers that can be p-doped or n-doped. Inject layer. The first reflector 1522 may comprise, for example, HCG, or be made of pairs of dielectric, semiconductor, or metallic material layers (doped or undoped) (such as GaAs and AlAs (or AlGaAs) layers having different refractive indices and thicknesses. , an oxide layer (eg, silicon oxide and another oxide layer) or the like). The active region 1524 may include, for example, an InGaAs quantum well layer and a GaAs barrier layer, an InAlGaAs quantum well layer and an AlGaAs barrier layer, or the like. In some embodiments, the VCSEL 1520 can include a partial reflector 1526 for the IR light, wherein the partial reflector 1526 can partially reflect and partially transmit the IR light emitted in the active region 1524 to form the VCSEL 1520 with the first reflector 1522 the resonant cavity. The resonant cavity formed by partial reflector 1526 and first reflector 1522 can help narrow and select the output wavelength range of the IR light emitted by VCSEL 1520 and improve the gain and intensity of the emitted IR light. In some embodiments, VCSEL 1520 may include polarizer 1528 . The polarizer 1528 can be used to control the polarization mode of the IR light emitted by the VCSEL 1520 and improve the coupling efficiency of the IR light into the microresonator by, for example, a grating coupler or a nanoresonator (e.g., metastructure), which can be Polarization dependent. In some embodiments, other polarization components such as waveplates, spatially varying polarizers, or spatially varying waveplates may be used instead to control the polarization state of the IR light emitted by VCSEL 1520 .

In the illustrated example, each visible light source 1502 may include a first microresonator 1550, a second microresonator 1560, and a third microresonator 1570 for using the IR light emitted by the VCSEL 1520 as The pump light produces visible light of different colors. The first microresonator 1550, the second microresonator 1560, and the third microresonator 1570 can have different individual designs, and thus can generate visible light of different colors using the same pump light. Different individual designs may include, for example, different combinations of loop shapes (eg, loops, ellipses, spirals, orbits, etc.), dimensions, materials (and thus refractive indices), and the like. For example, the shape, size and material of the third microresonator 1570 can be selected such that red light can be generated in the third microresonator 1570 by DFWM using IR light emitted by the VCSEL 1520 as pump light. A coupling structure 1572 (eg, a grating or a nanoresonator) may be configured to vertically couple red light generated in the third microresonator 1570 out of the third microresonator 1570 . Similarly, the shape, size and material of the second microresonator 1560 can be selected such that green light can be generated in the second microresonator 1560 by DFWM using the IR light emitted by the VCSEL 1520 as pump light. A coupling structure 1562 (eg, a grating or a nanoresonator) can be configured to vertically couple the green light generated in the second microresonator 1560 out of the second microresonator 1560 . The shape, size and material of the first microresonator 1550 can be selected such that blue light can be generated in the first microresonator 1550 by DFWM using the IR light emitted by the VCSEL 1520 as pump light. A coupling structure 1552 (eg, a grating or a nanoresonator) may be configured to vertically couple blue light generated in the first microresonator 1550 out of the first microresonator 1550 . The first microresonator 1550, the second microresonator 1560, and the third microresonator 1570 may be arranged vertically in any suitable order. In some embodiments, each visible light source 1502 can include two or more different microresonators configured to generate visible light in two or more colors. In some embodiments, each visible light source 1502 can include multiple microresonators, where at least two of the microresonators can be configured to generate visible light of the same color.

Visible light coupled out of first microresonator 1550, second microresonator 1560, and third microresonator 1570 can be coupled out of visible light source 1502 via second reflector 1530 with little or no loss due to the second Second reflector 1530 may be anti-reflective for visible light, as described above. Like the first reflector 1522, the second reflector 1530 may include, for example, HCG, or a DBR structure formed of multiple layers of dielectric, semiconductor, or metallic material with alternating refractive indices. The thickness and index of refraction of the dielectric, semiconductor, or metallic material layers in the DBR structure can be selected such that IR light reflected at adjacent interfaces between different materials can constructively interfere to enlarge the second reflector 1530 With respect to the total reflectivity of IR light, visible light reflected at adjacent interfaces between different materials at the same time can destructively interfere to reduce the total reflectivity of the second reflector 1530 for visible light. Thus, IR light emitted by VCSEL 1520 and not yet coupled into the microresonator may be reflected back to the microresonator by second reflector 1530 and/or first reflector 1522 and may be at least partially coupled into the microresonator to The efficiency of coupling the IR pump light into the microresonator and the efficiency of the visible light source 1502 is improved. Therefore, each visible light source 1502 can simultaneously emit visible light in different colors, wherein the intensity of the emitted visible light in different colors can be controlled by the driving voltage or current from the driving circuit 1510 . In the example shown in Figures 15A and 15B, the separate intensities of visible light representing each color emitted by the same visible light source may not be individually controllable. Therefore, visible light source array 1500 can be used as a light source in a BLU display, but not as a display pixel of an active display panel. The microresonators, coupling structures, and second reflector 1530 in visible light source 1502 can be formed before or after bonding VCSEL 1520 to driver circuit 1510 .

16A and 16B illustrate an example of an array of visible light sources 1600 in which each visible light source 1602 is configured to emit visible light in multiple colors and the respective intensity of visible light in each color can be individually controlled, according to certain embodiments. Compared to the array of visible light sources 1500, the array of visible light sources 1600 can not only have individual control of each visible light source 1602, but also have individual control of the microresonators in the same visible light source 1602, so that the emitted light exhibits each color The individual intensities of visible light can be individually tuned.

As illustrated in FIG. 16A , each visible light source 1602 in an array of visible light sources 1600 includes a plurality of microresonators in a vertical cavity formed by a first reflector 1622 and a second reflector 1630, wherein the plurality of microresonators are formed by The same IR VCSEL 1620 in the vertical cavity is pumped to produce visible light of different colors. The first reflector 1622 and the second reflector 1630 may have high reflectivity (eg, >80%, >85%, >90%, >95%, >99% or higher) for IR light. In some embodiments, the first reflector 1622 can have a high reflectivity (eg, >80%, >85%, >90%, >95%, >99%, or higher) for visible light. The second reflector 1630 may be anti-reflective for visible light. Visible light of different colors generated in the microresonator is vertically coupled out of the microresonator by the respective coupling structures and can be transmitted out of the vertical cavity through the second reflector 1630 .

Visible light source 1602 may include driver circuitry 1610 formed on a CMOS backplane that may be bonded directly or indirectly (eg, via an interposer or thin film transistor layer) to a wafer including VCSELs 1620 fabricated thereon. The plurality of microresonators and the second reflector 1630 can be formed before or after bonding the wafer including the VCSEL 1620 to the CMOS backplane. The VCSEL 1620 may include a first electrode 1640 (eg, an anode or a cathode), a second electrode 1642 , and a semiconductor structure (eg, an epitaxial layer) formed between the first electrode 1640 and the second electrode 1642 . The semiconductor structure can include, for example, a first reflector 1622, an active region 1624 that can emit IR light, and other semiconductor layers (not labeled in FIG. 16A ), such as cladding layers or carrier layers that can be p-doped or n-doped. Inject layer. The first reflector 1622 may comprise, for example, HCG, or be made of pairs of dielectric, semiconductor, or metallic material layers (doped or undoped) (such as GaAs and AlAs (or AlGaAs) layers having different refractive indices and thicknesses. , an oxide layer (eg, silicon oxide and another oxide layer) or the like). The active region 1624 may include, for example, an InGaAs quantum well layer and a GaAs barrier layer, an InAlGaAs quantum well layer and an AlGaAs barrier layer, or the like. In some embodiments, the VCSEL 1620 can include a partial reflector 1626 for the IR light, wherein the partial reflector 1626 can partially reflect and partially transmit the IR light emitted in the active region 1624 to form the VCSEL 1620 with the first reflector 1622 the resonant cavity. The resonant cavity formed by partial reflector 1626 and first reflector 1622 can help narrow and select the output wavelength range of the IR light emitted by IR VCSEL 1620 and improve the gain and intensity of the emitted IR light. In some embodiments, VCSEL 1620 may include polarizer 1628 . Polarizer 1628 can be used to control the polarization mode of the IR light emitted by VCSEL 1620 and improve the coupling efficiency of IR light into the microresonator by, for example, a grating coupler or nanoresonator (e.g., metastructure), which can be Polarization dependent. In some embodiments, other polarization components such as waveplates, spatially varying polarizers, or spatially varying waveplates may be used instead to control the polarization state of the IR light emitted by VCSEL 1620 .

In the illustrated example, each visible light source 1602 may include a first microresonator 1650, a second microresonator 1660, and a third microresonator 1670 for using the IR light emitted by the VCSEL 1620 as The pump light produces visible light of different colors. The first microresonator 1650, the second microresonator 1660, and the third microresonator 1670 can have different individual designs, and thus can generate visible light of different colors using the same pump light. Different individual designs may include, for example, different combinations of loop shapes (eg, loops, ellipses, spirals, orbits, etc.), dimensions, materials (and thus refractive indices), and the like. For example, the shape, size and material of the third microresonator 1670 can be selected such that red light can be generated in the third microresonator 1670 by DFWM using IR light emitted by the VCSEL 1620 as pump light. A coupling structure 1672 (eg, a grating or a nanoresonator) can be configured to vertically couple red light generated in the third microresonator 1670 out of the third microresonator 1670 . Similarly, the shape, size and material of the second microresonator 1660 can be selected such that green light can be generated in the second microresonator 1660 by DFWM using the IR light emitted by the VCSEL 1620 as pump light. A coupling structure 1662 (eg, a grating or a nanoresonator) may be configured to vertically couple green light generated in the second microresonator 1660 out of the second microresonator 1660 . The shape, size and material of the first microresonator 1650 can be selected such that blue light can be generated in the first microresonator 1650 by DFWM using the IR light emitted by the VCSEL 1620 as pump light. A coupling structure 1652 (eg, a grating or a nanoresonator) may be configured to vertically couple blue light generated in the first microresonator 1650 out of the first microresonator 1650 . The first microresonator 1650, the second microresonator 1660, and the third microresonator 1670 may be arranged vertically in any suitable order. In some embodiments, each visible light source 1602 can include two or more different microresonators configured to generate visible light in two or more colors. In some embodiments, each visible light source 1602 can include multiple microresonators, where at least two of the microresonators can be configured to generate the same color of visible light.

Visible light coupled out of first microresonator 1650, second microresonator 1660, and third microresonator 1670 can be coupled out of visible light source 1602 via second reflector 1630 with little or no loss due to the second Second reflector 1630 may be anti-reflective for visible light, as described above. Like the first reflector 1622, the second reflector 1630 may include, for example, HCG, or a DBR structure formed of multiple layers of dielectric, semiconductor, or metallic material with alternating refractive indices. The thickness and index of refraction of the dielectric, semiconductor, or metallic material layers in the DBR structure can be selected such that IR light reflected at adjacent interfaces between different materials can constructively interfere to enlarge the second reflector 1630 With respect to the total reflectivity of IR light, visible light reflected at adjacent interfaces between different materials at the same time can destructively interfere to reduce the total reflectivity of the second reflector 1630 for visible light. Thus, IR light emitted by VCSEL 1620 and not yet coupled into the microresonator may be reflected back to the microresonator by second reflector 1630 and/or first reflector 1622 and may be at least partially coupled into the microresonator to The efficiency of coupling the IR pump light into the microresonator and the efficiency of the visible light source 1602 is improved. The microresonators, coupling structures, and second reflector 1630 in visible light source 1602 can be formed before or after bonding VCSEL 1620 to driver circuit 1610 .

Visible light source 1602 may include additional electrodes for tuning the respective intensity of each color of visible light generated by and coupled out of a corresponding microresonator. For example, electrode 1690 can be used to modulate the intensity of blue light coupled out of first microresonator 1650, electrode 1692 can be used to modulate the intensity of green light coupled out of second microresonator 1660, and electrode 1694 can be used to modulate the intensity of blue light coupled out of first microresonator 1650. The intensity of the red light coupled out of the third microresonator 1670 is varied. Electrode 1690 may be used to tune at least one of the following to modulate the intensity of blue light emitted from visible light source 1602: first microresonator 1650, for coupling IR light emitted by VCSEL 1620 into first microresonator 1650 The coupling structure, or the coupling structure 1652 for coupling the blue light generated in the first microresonator 1650. For example, the electrodes 1690 can be used to apply a voltage across the electro-optic material or supply a current signal to a thermo-optic device to change the refractive index of the first microresonator 1650 or the coupling structure, thereby changing the resonant condition of the first microresonator 1650 or The coupling efficiency of the coupling structure of the first microresonator 1650, and thus changes the intensity of the emitted blue light. Similarly, electrode 1692 can be used to change the resonance conditions of second microresonator 1660 or the coupling efficiency of the coupling structure of second microresonator 1660, and thus change the intensity of emitted green light. The electrodes 1694 can be used to change the resonance conditions of the third microresonator 1670 or the coupling efficiency of the coupling structure of the third microresonator 1670, and thus change the intensity of the emitted red light. In this way, the intensities of red, green, and blue light emitted by visible light source 1602 can be independently tuned to desired values to represent color pixel units of an active display panel as shown in FIG. The pitch can be less than about 50 μm, less than about 30 μm, less than about 20 μm, or less than about 10 μm.

17A and 17B illustrate an example of a visible light source 1700 that is tuneable to emit different colors of visible light , according to certain embodiments. Visible light source 1700 may be an example of a visible light source in an array of visible light sources. FIG. 17A shows a cross-sectional view of visible light source 1700 and FIG. 17B illustrates a top view of visible light source 1700 . Visible light source 1700 includes microresonators in a tunable vertical cavity that are directly pumped by a tunable infrared VCSEL in the tunable vertical cavity to generate visible light of different colors. Visible light generated in the microresonator is coupled vertically out of the vertical cavity. Compared to visible light source 1502 or 1602, visible light source 1700 may include a single microresonator that can generate different colors of light at different times.

In the illustrated example, visible light source 1700 includes a microresonator 1740 in a tunable vertical cavity formed by a first reflector 1722 and a second reflector 1750, which may be formed in a microelectromechanical system (MEMS) on and thus movable by the MEMS device 1770 . In some embodiments, other microactuators or nanoactuators (such as micromotors, piezoelectric actuators, ferroelectric actuators, magnetic actuators, ultrasonic actuators, or the like) can be used to move the second reflector 1750 . The first reflector 1722 and the second reflector 1750 may have high reflectivity (eg, >80%, >85%, >90%, >95%, >99% or higher) for IR light. In some embodiments, the first reflector 1722 can have a high reflectivity (eg, >80%, >85%, >90%, >95%, >99%, or higher) for visible light. The second reflector 1750 may be anti-reflective for visible light. The microresonator 1740 can be pumped by the IR emitting VCSEL 1720 in the vertical cavity to generate visible light. Visible light generated in microresonator 1740 can be vertically coupled out of microresonator 1740 by coupling structure 1742 and can be transmitted out of the vertical cavity through second reflector 1750 .

Visible light source 1700 may include driver circuitry 1710 formed on a CMOS backplane that may be bonded directly or indirectly (eg, via an interposer or TFT layer) to a wafer including VCSELs 1720 fabricated thereon. Microresonator 1740 and second reflector 1750 may be formed before or after bonding the wafer including VCSEL 1720 to the CMOS backplane. The VCSEL 1720 may include a first electrode 1730 (eg, an anode or a cathode), a second electrode 1732 , and a semiconductor structure (eg, an epitaxial layer) formed between the first electrode 1730 and the second electrode 1732 . The semiconductor structure can include, for example, a first reflector 1722, an active region 1724 that can emit IR light, and other semiconductor layers (not labeled in FIG. 17A ), such as cladding layers or carrier layers that can be p-doped or n-doped. Inject layer. The first reflector 1722 may include, for example, HCG, or be made of pairs of dielectric, semiconductor, or metallic material layers (doped or undoped) (such as GaAs and AlAs (or AlGaAs) layers having different refractive indices and thicknesses. , an oxide layer (eg, silicon oxide and another oxide layer) or the like). The active region 1724 may include, for example, an InGaAs quantum well layer and a GaAs barrier layer, an InAlGaAs quantum well layer and an AlGaAs barrier layer, or the like. VCSEL 1720 may optionally include a partial reflector 1726 for IR light, wherein partial reflector 1726 may partially reflect and partially transmit IR light emitted in active region 1724 to form a resonant cavity of VCSEL 1720 with first reflector 1722 . The resonant cavity formed by partial reflector 1726 and first reflector 1722 can help select the output wavelength range of the IR light emitted by VCSEL 1720 and improve the gain and intensity of the emitted IR light. In some embodiments, VCSEL 1720 may include polarizer 1728 . Polarizer 1728 can be used to control the polarization state of the IR light emitted by VCSEL 1720 and improve the coupling efficiency of IR light into the microresonator by, for example, a grating coupler or nanoresonator (e.g., metastructure), which can be Polarization dependent. In some embodiments, other polarization components such as waveplates, spatially varying polarizers, or spatially varying waveplates may be used instead to control the polarization state of the IR light emitted by VCSEL 1720 .

Like the first reflector 1722, the second reflector 1750 may comprise, for example, HCG, or a DBR structure formed of multiple layers of dielectric, semiconductor, or metallic material with alternating refractive indices. The thickness and index of refraction of the dielectric, semiconductor, or metallic material layers in the DBR structure can be selected such that IR light reflected at adjacent interfaces between different materials can constructively interfere to enlarge the second reflector 1750 With respect to the total reflectivity of IR light, visible light reflected at adjacent interfaces between different materials at the same time can destructively interfere to reduce the total reflectivity of the second reflector 1750 for visible light. Thus, IR light emitted by VCSEL 1720 and not yet coupled into microresonator 1740 may be reflected back to microresonator 1740 by second reflector 1750 and/or first reflector 1722 such that IR light emitted by VCSEL 1720 may be reflected at The vertical intracavity oscillation formed by the first reflector 1722 and the second reflector 1750 can be coupled into the microresonator 1740 with higher coupling efficiency to improve the efficiency of the visible light source 1700 .

The wavelength at which IR light resonates in the vertical cavity can be determined from the optical path length of the vertical cavity. Thus, when the second reflector 1750 is moved by the MEMS device 1770 and thus the optical path length of the vertical cavity changes, the wavelength of the IR light resonating in the vertical cavity can be changed. IR light can be coupled into microresonator 1740 directly or via a coupling structure (eg, a grating or nanoresonator). The shape, size, and material of the microresonator 1740 can be selected such that when the wavelength of the pump light is changed by tuning the optical path length of the vertical cavity using the MEMS device 1770, the microresonator can be resonated via an OPO (eg, DFWM) procedure. Visible light of different colors is generated in the device 1740 . Coupling structure 1742 (eg, a grating or nanoresonator) may be configured to vertically couple visible light generated in microresonator 1740 out of microresonator 1740 . Visible light coupled out of microresonator 1740 can be coupled out of visible light source 1700 via second reflector 1750 with little or no loss since second reflector 1750 can be anti-reflective for visible light, as described above .

17C and 17D illustrate an example of generating different colors of visible light by tuning the visible light source 1700 . 7C shows that pump light emitted by VCSEL 1720 and oscillating within the vertical cavity formed by first reflector 1722 and second reflector 1750 can be tuned by using MEMS device 1770 or another actuator. The orientation of the 1750 is continuously tuned to tune the optical path length and thus the resonant wavelength of the vertical cavity. In the illustrated example, the MEMS device 1770 can be driven by a control signal that moves the second reflector 1750 such that the wavelength of the IR light emitted by the VCSEL 1720 and oscillating within the vertical cavity can be varied linearly in time, as in FIG. 7C Shown by curve 1780 . When the wavelength of the IR pump light is tuned to a first value, the resonance conditions of the microresonator 1740 can be met and an OPO process can occur to generate signal light 1790 at a first visible wavelength (eg, red light). When the wavelength of the IR pump light is tuned to a second value, the resonance conditions of the microresonator 1740 (for a different mode m) can be met again and the OPO process can occur to operate at a second visible wavelength (e.g., green light) Signal light 1792 is generated. When the wavelength of the IR pump light is tuned to a third value, the resonance conditions of the microresonator 1740 (for a different mode m) can be met again and the OPO process can occur to operate at a third visible wavelength (e.g., blue light) Signal light 1794 is generated. In this way, visible light in many different colors can be generated by visible light source 1700 .

The control signal may be a periodic signal or may be aperiodic. In some embodiments, the control signal may have a more complex waveform determined by the pixel data of the image to be displayed. For example, the control signal can have a plurality of different synchronization levels corresponding to different colors, wherein the duration of each step level of the color pixels in the image frame to be displayed can be based on the corresponding color pixels of the image frame The desired intensity of the color (e.g., R, G, B values) is determined so that the temporal combination of visible light emitted during different periods of the image frame exhibiting different colors can be perceived by the viewer's eyes because visible light has A single color in the Rec. 2020 color gamut or larger. In this way, each visible light source 1700 can be individually controlled to emit light of a desired color at a desired intensity in each image frame. Therefore, the visible light source array 1700 can be used as an active display panel.

18A and 18B illustrate an example of an array of visible light sources 1800 in which each visible light source 1802 in the array of visible light sources 1800 is configured to emit visible light in one or more colors and to represent each color of visible light in each color, according to certain embodiments. The intensity can be controlled individually. As illustrated in FIG. 18A , the visible light source 1802 can include one or more microresonators in a tunable vertical cavity formed by a first reflector 1822 and a second reflector 1830, which can be formed in a MEMS on and thus movable by the MEMS device 1832 . The first reflector 1822 and the second reflector 1830 may have high reflectivity (eg, >80%, >85%, >90%, >95%, >99% or higher) for IR light. In some embodiments, the first reflector 1822 can have a high reflectivity (eg, >80%, >85%, >90%, >95%, >99%, or higher) for visible light. The second reflector 1830 may be anti-reflective for visible light. One or more microresonators can be directly pumped by the infrared light VCSEL 1820 in the tunable vertical cavity to generate visible light of different colors. Visible light generated in one or more microresonators can be coupled vertically out of the vertical cavity.

Visible light source 1802 may include driver circuitry 1810 formed on a CMOS backplane that may be bonded directly or indirectly (eg, via an interposer or thin film transistor layer) to a wafer including VCSELs 1820 fabricated thereon. The plurality of microresonators and the second reflector 1830 may be formed before or after bonding the wafer including the VCSEL 1820 to the CMOS backplane. The VCSEL 1820 may include a first electrode 1840 (eg, an anode or a cathode), a second electrode 1842 , and a semiconductor structure (eg, an epitaxial layer) formed between the first electrode 1840 and the second electrode 1842 . The semiconductor structure can include, for example, a first reflector 1822, an active region 1824 that can emit IR light, and other semiconductor layers (not labeled in FIG. 18A ), such as cladding layers or carrier layers that can be p-doped or n-doped. Inject layer. The first reflector 1822 may include, for example, HCG, or be made of pairs of dielectric, semiconductor, or metallic material layers (doped or undoped) (such as GaAs and AlAs (or AlGaAs) layers having different refractive indices and thicknesses. , an oxide layer (eg, silicon oxide and another oxide layer) or the like). The active region 1824 may include, for example, an InGaAs quantum well layer and a GaAs barrier layer, an InAlGaAs quantum well layer and an AlGaAs barrier layer, or the like. In some embodiments, the VCSEL 1820 can include a partial reflector 1826 for the IR light, wherein the partial reflector 1826 can partially reflect and partially transmit the IR light emitted in the active region 1824 to form the VCSEL 1820 with the first reflector 1822 the resonant cavity. The resonant cavity formed by partial reflector 1826 and first reflector 1822 can help narrow and select the output wavelength range of the IR light emitted by IR VCSEL 1820 and improve the gain and intensity of the emitted IR light. In some embodiments, VCSEL 1820 may include polarizer 1828 . Polarizer 1828 can be used to control the polarization mode of the IR light emitted by VCSEL 1820 and improve the coupling efficiency of IR light into the microresonator by, for example, a grating coupler or nanoresonator (e.g., metastructure), which can be Polarization dependent. In some embodiments, other polarization components such as waveplates, spatially varying polarizers, or spatially varying waveplates may be used instead to control the polarization state of the IR light emitted by VCSEL 1820 .

In the illustrated example, each visible light source 1802 may include a first microresonator 1850, a second microresonator 1860, and a third microresonator 1870 for using the IR light emitted by the VCSEL 1820 as The pump light produces visible light of different colors. The first microresonator 1850, the second microresonator 1860, and the third microresonator 1870 can have different individual designs, and thus can generate visible light of different colors using the same pump light. Different individual designs may include, for example, different combinations of loop shapes (eg, loops, ellipses, spirals, orbits, etc.), dimensions, materials (and thus refractive indices), and the like. For example, the shape, size and material of the third microresonator 1870 can be selected such that red light can be generated in the third microresonator 1870 by DFWM using IR light emitted by the VCSEL 1820 as pump light. A coupling structure 1872 (eg, a grating or a nanoresonator) may be configured to vertically couple red light generated in the third microresonator 1870 out of the third microresonator 1870 . Similarly, the shape, size and material of the second microresonator 1860 can be selected such that green light can be generated in the second microresonator 1860 by DFWM using the IR light emitted by the VCSEL 1820 as pump light. A coupling structure 1862 (eg, a grating or a nanoresonator) can be configured to vertically couple the green light generated in the second microresonator 1860 out of the second microresonator 1860 . The shape, size and material of the first microresonator 1850 can be selected such that blue light can be generated in the first microresonator 1850 by DFWM using the IR light emitted by the VCSEL 1820 as pump light. A coupling structure 1852 (eg, a grating or a nanoresonator) can be configured to vertically couple blue light generated in the first microresonator 1850 out of the first microresonator 1850 . The first microresonator 1850, the second microresonator 1860, and the third microresonator 1870 may be arranged vertically in any suitable order. In some embodiments, each visible light source 1802 can include two or more different microresonators configured to generate visible light in two or more colors. In some embodiments, each visible light source 1802 can include a plurality of microresonators, wherein at least two microresonators in the plurality of microresonators can be configured to generate visible light of the same color.

Visible light coupled out of first microresonator 1850, second microresonator 1860, and third microresonator 1870 can be coupled out of visible light source 1802 via second reflector 1830 with little or no loss due to the second Second reflector 1830 may be anti-reflective for visible light, as described above. Like the first reflector 1822, the second reflector 1830 may comprise, for example, HCG, or a DBR structure formed of multiple layers of dielectric, semiconductor, or metallic material with alternating refractive indices. The thickness and index of refraction of the dielectric, semiconductor, or metallic material layers in the DBR structure can be selected such that IR light reflected at adjacent interfaces between different materials can constructively interfere to enlarge the second reflector 1830 With respect to the total reflectivity of IR light, visible light reflected at adjacent interfaces between different materials at the same time can destructively interfere to reduce the total reflectivity of the second reflector 1830 for visible light. Thus, IR light emitted by VCSEL 1820 and not yet coupled into the microresonator may be reflected back to the microresonator by second reflector 1830 and/or first reflector 1822 and may be at least partially coupled into the microresonator to The efficiency of coupling the IR pump light into the microresonator and the efficiency of the visible light source 1802 is improved. The microresonators, coupling structures, and second reflector 1830 in the visible light source 1802 can be formed before or after bonding the VCSEL 1820 to the driver circuit 1810 .

As illustrated in FIG. 18A , the second reflector 1830 may be formed on the MEMS device 1832 and thus may be movable by the MEMS device 1832 . In some embodiments, other microactuators or nanoactuators (such as micromotors, piezoelectric actuators, ferroelectric actuators, magnetic actuators, ultrasonic actuators, or the like) can be used to move the second reflector 1830 . The wavelength at which IR light resonates in the vertical cavity can be determined from the optical path length of the vertical cavity. Thus, when the second reflector 1830 is moved by the MEMS device 1832 and thus the optical path length of the vertical cavity changes, the wavelength of the IR light resonating in the vertical cavity can be changed. When the wavelength of the pump light is changed by tuning the optical path length of the vertical cavity using the MEMS device 1832, the different colors of visible light generated in the microresonators 1850, 1860, and 1870 via the OPO (eg, DFWM) process can also be changed wavelength.

In the illustrated example, visible light source 1802 may include additional electrodes for tuning the respective intensities of each color of visible light generated by and coupled out of a corresponding microresonator. For example, electrode 1890 can be used to modulate the intensity of blue light coupled out of first microresonator 1850, electrode 1892 can be used to modulate the intensity of green light coupled out of second microresonator 1860, and electrode 1894 can be used to modulate the intensity of blue light coupled out of first microresonator 1850. The intensity of the red light coupled out of the third microresonator 1870 was varied. Electrode 1890 may be used to tune at least one of the following to modulate the intensity of blue light emitted from visible light source 1802: first microresonator 1850, for coupling IR light emitted by VCSEL 1820 into first microresonator 1850 coupling structure, or a coupling structure 1852 for coupling the blue light generated in the first microresonator 1850. For example, the electrodes 1890 can be used to apply a voltage across the electro-optic material or supply a current signal to a thermo-optic device to change the refractive index of the first microresonator 1850 or the coupling structure, thereby changing the resonant condition of the first microresonator 1850 or The coupling efficiency of the coupling structure of the first microresonator 1850, and thus changes the intensity of the emitted blue light. Similarly, electrode 1892 can be used to change the resonance conditions of second microresonator 1860 or the coupling efficiency of the coupling structure of second microresonator 1860, and thus change the intensity of emitted green light. The electrodes 1894 can be used to change the resonance conditions of the third microresonator 1870 or the coupling efficiency of the coupling structure of the third microresonator 1870, and thus change the intensity of the emitted red light. In this way, the intensities of red, green, and blue light emitted by visible light source 1802 can be independently tuned to desired values to represent color pixel units of an active display panel as shown in FIG. The pitch can be less than about 50 μm, less than about 30 μm, less than about 20 μm, or less than about 10 μm.

The visible light sources described in Figures 15A to 17B can use one VCSEL in a vertical cavity to generate light of multiple colors, such as the three primary colors and other colors that make up combinations of the three primary colors. The temporal combination of different colors of spatially multiplexed (overlapped) visible light produced by spatially overlapping microresonators in visible light sources 1502 and 1602 or different colors of light produced by a single microresonator in visible light source 1700 during different time periods can be determined by The viewer's eyes perceive a single color in the color gamut. Thus, an array of visible light sources including the visible light sources described in FIGS. 15A-17B can have smaller pixel sizes and smaller pixel pitches than the visible light sources described in FIGS. The spatial combination of three visible light sources is achieved.

Embodiments disclosed herein may be used to implement components of an artificial reality system, or may be implemented in conjunction with an artificial reality system. Artificial reality is a form of reality that has been modified in some way before being presented to the user, which may include, for example, virtual reality, augmented reality, mixed reality, hybrid reality, or some combination and/or derivative thereof things. Artificial reality content may include fully generated content or generated content combined with captured (eg, real world) content. Artificial reality content may include video, audio, haptic feedback, or some combination thereof, and any of these may be presented in a single channel or in multiple channels (such as stereoscopic video that creates a three-dimensional effect on the viewer). Additionally, in some embodiments, AR can also be used with applications used, for example, to generate content in AR and/or otherwise used in AR (e.g., to perform activities in AR) , products, accessories, services or a combination thereof. AR systems that provide AR content can be implemented on a variety of platforms including HMDs connected to a host computer system, standalone HMDs, mobile devices or computing systems or capable of delivering AR content to one or more viewers any other hardware platform.

19 is a simplified block diagram of an example electronic system 1900 for implementing an example near-eye display (eg, an HMD device) some of the examples disclosed herein . Electronic system 1900 may be used as the electronic system of an HMD device or other near-eye display described above. In this example, electronic system 1900 may include one or more processors 1910 and memory 1920 . Processor 1910 may be configured to execute instructions for operations at several components, and may be, for example, a general purpose processor or microprocessor suitable for implementation within a portable electronic device. Processor 1910 may be communicatively coupled with a plurality of components within electronic system 1900 . To achieve this communicative coupling, processor 1910 may communicate across bus 1940 with the other illustrated components. Bus 1940 may be any subsystem suitable for communicating data within electronic system 1900 . Bus 1940 may include a plurality of computer buses and additional circuitry to transmit data.

The memory 1920 can be coupled to the processor 1910 . In some embodiments, memory 1920 can provide both short-term and long-term storage, and can be divided into units. Memory 1920 may be volatile, such as static random access memory (SRAM) and/or dynamic random access memory (DRAM), and/or may be non-volatile, such as read-only memory (read-only memory; ROM), flash memory, and the like. In addition, the memory 1920 may include a removable storage device, such as a secure digital (SD) card. Memory 1920 may provide storage of computer readable instructions, data structures, program modules, and other data for electronic system 1900 . In some specific examples, the memory 1920 can be distributed among different hardware modules. A set of instructions and/or program code can be stored on memory 1920 . The instructions may be in the form of executable code executable by the electronic system 1900, and/or may be in the form of source code and/or installable code that resides in the electronic system Executable code may be in the form of executable code after being compiled on the 1900 and/or installed on the electronic system (eg, using any of a number of commonly available compilers, installers, compression/decompression utilities, etc.).

In some embodiments, the memory 1920 can store a plurality of application program modules 1922 to 1924, and the application program modules 1922 to 1924 can include any number of application programs. Examples of applications may include game applications, conference applications, video playback applications, or other suitable applications. Apps can include depth-sensing capabilities or eye-tracking capabilities. Application modules 1922-1924 may include specific instructions to be executed by processor 1910. In some embodiments, certain applications or portions of application modules 1922 - 1924 may be executed by other hardware modules 1980 . In some embodiments, memory 1920 may additionally include secure memory, which may include additional security controls to prevent copying or other unauthorized access to secure information.

In some embodiments, the memory 1920 may include an operating system 1925 loaded therein. Operating system 1925 is operable to initiate execution of instructions provided by application modules 1922-1924 and/or to manage other hardware modules 1980, and to interface with wireless communication subsystem 1930, which may include one or more wireless transceivers . Operating system 1925 may be adapted to perform other operations across components of electronic system 1900, including thread processing, resource management, data storage control, and other similar functionality.

Wireless communication subsystem 1930 may include, for example, infrared communication devices, wireless communication devices and/or chipsets (such as Bluetooth® devices, IEEE 802.11 devices, Wi-Fi devices, WiMax devices, cellular communication facilities, etc.) and/or similar communication interface. Electronic system 1900 may include one or more antennas 1934 for wireless communications as part of wireless communications subsystem 1930 or as a separate component coupled to any portion of the system. Depending on desired functionality, the wireless communication subsystem 1930 may include independent transceivers to communicate with base transceiver stations and other wireless devices and access points, which may include communication with wireless wide-area network (WWAN) , wireless local area network (wireless local area network; WLAN) or wireless personal area network (wireless personal area network; WPAN) of different data networks and/or network types to communicate. A WWAN may be, for example, a WiMax (IEEE 802.16) network. The WLAN can be, for example, an IEEE 802.11x network. A WPAN can be, for example, a Bluetooth network, IEEE 802.15x, or some other type of network. The techniques described herein may also be used for any combination of WWAN, WLAN, and/or WPAN. Wireless communication subsystem 1930 may permit the exchange of data with a network, other computer systems, and/or any other devices described herein. Wireless communication subsystem 1930 may include components for transmitting or receiving data using antenna 1934 and wireless link 1932, such as an identifier of the HMD device, location data, topographical maps, heat maps, photos, or video. Together, the wireless communication subsystem 1930, the processor 1910, and the memory 1920 may comprise at least a portion of one or more of the means for performing some of the functions disclosed herein.

Embodiments of electronic system 1900 may also include one or more sensors 1990 . Sensors 1990 may include, for example, image sensors, accelerometers, pressure sensors, temperature sensors, proximity sensors, magnetometers, gyroscopes, inertial sensors (eg, a combination accelerometer and gyroscope) module), an ambient light sensor, or any other module operable to provide a sensory output and/or receive a sensory input, such as a depth sensor or a position sensor. For example, in some implementations, sensors 1990 may include one or more IMUs and/or one or more position sensors. The IMU may generate calibration data indicating an estimated position of the HMD device relative to an initial position of the HMD device based on measurement signals received from one or more of the position sensors. The position sensor may generate one or more measurement signals in response to motion of the HMD device. Examples of position sensors may include, but are not limited to, one or more accelerometers, one or more gyroscopes, one or more magnetometers, another suitable type of sensor to detect motion, error for an IMU Calibration of a type of sensor or any combination thereof. The position sensors can be located external to the IMU, internal to the IMU, or any combination thereof. At least some sensors can use structured light patterns for sensing.

The electronic system 1900 can include a display module 1960 . The display module 1960 can be a near-eye display, and can present information from the electronic system 1900 (such as images, videos, and various instructions) to the user in a graphical manner. This information may originate from one or more application modules 1922-1924, virtual reality engine 1926, one or more other hardware modules 1980, combinations thereof, or be used to parse graphical content for the user (e.g., by by any other suitable component of the operating system 1925). The display module 1960 may use LCD technology, LED technology (including OLED, ILED, μ-LED, AMOLED, TOLED, etc.), light-emitting polymer display (LPD) technology, or some other display technology.

The electronic system 1900 also includes a user input/output module 1970 . The user input/output module 1970 can allow the user to send action requests to the electronic system 1900 . An action request may be a request to perform a specific action. For example, an action request may start or end an application or perform a specific action within the application. The user input/output module 1970 may include one or more input devices. Example input devices may include touch screens, trackpads, microphones, buttons, dials, switches, keyboards, mice, game controllers, or devices for receiving action requests and communicating received action requests to the electronic system 1900. any other suitable device. In some embodiments, the user input/output module 1970 can provide tactile feedback to the user according to commands received from the electronic system 1900 . For example, haptic feedback may be provided when a motion request is received or has been performed.

The electronic system 1900 can include a camera 1950, which can be used to take pictures or videos of the user, for example to track the position of the user's eyes. The camera 1950 can also be used to take pictures or videos of the environment, such as for VR, AR or MR applications. The camera 1950 may include, for example, a complementary metal-oxide-semiconductor (CMOS) image sensor with millions or tens of millions of pixels. In some implementations, camera 1950 may include two or more cameras that may be used to capture 3-D images.

In some specific examples, the electronic system 1900 may include a plurality of other hardware modules 1980 . Each of the other hardware modules 1980 may be a physical module within the electronic system 1900 . While each of the other hardware modules 1980 may be permanently configured as a structure, some of the other hardware modules 1980 may be temporarily configured to perform a specific function or temporarily activated. Examples of other hardware modules 1980 may include, for example, audio output and/or input modules (eg, microphones or speakers), near field communication (NFC) modules, rechargeable batteries, battery management systems, wired / wireless battery charging system, etc. In some embodiments, one or more functions of other hardware modules 1980 can be implemented by software.

In some specific examples, the memory 1920 of the electronic system 1900 can also store the virtual reality engine 1926 . The virtual reality engine 1926 can execute applications within the electronic system 1900 and receive position information, acceleration information, velocity information, predicted future position, or any combination thereof of the HMD device from various sensors. In some embodiments, information received by the virtual reality engine 1926 may be used to generate signals (eg, display commands) for the display module 1960 . For example, if the received information indicates that the user has looked to the left, the virtual reality engine 1926 may generate content for the HMD device that reflects the user's movement in the virtual environment. Additionally, the virtual reality engine 1926 can perform in-app actions in response to action requests received from the user input/output module 1970 and provide feedback to the user. The feedback provided may be visual, auditory or tactile feedback. In some implementations, the processor 1910 can include one or more GPUs that can execute a virtual reality engine 1926 .

In various implementations, the hardware and modules described above may be implemented on a single device or on multiple devices that can communicate with each other using wired or wireless connections. For example, in some implementations, some components or modules such as a GPU, a virtual reality engine 1926, and applications (e.g., a tracking application) may be implemented on a console that is connected to a head-mounted display device separate. In some implementations, a console can connect to or support more than one HMD.

In alternative configurations, different components and/or additional components may be included in electronic system 1900 . Similarly, the functionality of one or more of the components may be distributed among the components in ways other than that described above. For example, in some embodiments electronic system 1900 may be modified to include other system environments, such as an AR system environment and/or a MR environment.

The methods, systems, and devices discussed above are examples. Various embodiments may omit, substitute, or add various procedures or components as appropriate. For example, in alternative configurations, the methods described may be performed in an order different from that described, and/or various stages may be added, omitted, and/or combined. Furthermore, features described with respect to certain embodiments may be combined in various other embodiments. Different aspects and elements of the embodiments can be combined in a similar manner. In addition, technology evolves, and thus many of the elements are examples that do not limit the scope of the disclosure to those particular examples.

Specific details are given in the specification to provide a thorough understanding of specific examples. However, specific examples may be practiced without such specific details. For example, well-known circuits, procedures, systems, structures and techniques have been shown without unnecessary detail in order not to obscure the particular example. This description provides example specific examples only, and is not intended to limit the scope, applicability, or configuration of the invention. Rather, the foregoing descriptions of the specific examples will provide those having ordinary skill in the art with a description that can enable the various specific examples to be practiced. Various changes may be made in the function and arrangement of elements without departing from the spirit and scope of the invention.

It will be apparent to those skilled in the art that substantial changes may be made according to particular requirements. For example, custom or dedicated hardware may also be used, and/or particular elements may be implemented in hardware, software (including portable software, such as applets, etc.), or both. Additionally, connections to other computing devices, such as network input/output devices, may be employed.

Referring to the accompanying drawings, components that may include memory may include non-transitory machine-readable media. The terms "machine-readable medium" and "computer-readable medium" may refer to any storage medium that participates in providing data that causes a machine to operate in a specific manner. In the specific examples provided above, various machine-readable media may be involved in providing instructions/code to a processing unit and/or other device for execution. Additionally or alternatively, a machine-readable medium may be used to store and/or carry such instructions/code. In many implementations, a computer readable medium is a physical and/or tangible storage medium. This medium can take many forms, including but not limited to, non-volatile media, volatile media, and transmission media. Common forms of computer readable media include, for example, magnetic and/or optical media such as compact disks (CDs) or digital versatile disks (digital versatile disks (DVDs); punched cards; paper tape; any Other physical media; RAM; programmable read-only memory (PROM); erasable programmable read-only memory (EPROM); FLASH-EPROM; any other memory chips or cartridges; carrier waves as described below; or any other medium from which instructions and/or code can be read. A computer program product may include code and/or machine-executable instructions which may represent a program, function, subroutine, program, routine, application (App), subroutine , module, package, class, or any combination of instructions, data structures, or program statements.

As used herein, the terms "and" and "or" may include a variety of meanings that are also expected to depend at least in part on the context in which such terms are used. In general, "or" when used in relation to a list, such as A, B, or C, is intended to mean A, B, and C (herein used inclusively), and A, B, or C (herein used in an exclusive sense) . In addition, as used herein, the term "one or more" may be used to describe any feature, structure or characteristic in the singular or may be used to describe some combination of features, structures or characteristics. It should be noted, however, that this is merely an illustrative example and that claimed subject matter is not limited to this example. In addition, the term "at least one of" when applied to an associated listing (such as A, B or C) may be construed to mean A, B, C or a combination of A, B and/or C (such as AB , AC, BC, AA, ABC, AAB, AABBCCC or the like).

Furthermore, while certain specific examples have been described using specific combinations of hardware and software, it should be recognized that other combinations of hardware and software are possible. Some embodiments may be implemented in hardware only or software only or using a combination thereof. In one example, the software can be implemented by a computer program product containing computer code or instructions executable by one or more processors for performing the functions described herein. Any or all of the steps, operations or procedures, wherein the computer program can be stored on a non-transitory computer readable medium. The various programs described herein can be implemented in any combination on the same processor or on different processors.

Where a device, system, component or module is described as being configured to perform certain operations or functions, it may be possible, for example, by designing electronic circuits to perform the operations, by programming programmable electronic circuits such as microprocessors ) to perform operations such as by executing computer instructions or code, or a processor or core programmed to execute code or instructions stored on a non-transitory memory medium, or any combination thereof. Programs may communicate using a variety of techniques, including but not limited to well-known techniques for communicating between programs, and different pairs of programs may use different techniques, or the same pair of programs may use different techniques at different times.

Accordingly, the specification and drawings should be regarded in an illustrative sense rather than a restrictive sense. It will be apparent, however, that additions, subtractions, deletions, and other modifications and changes may be made to the specification and drawings without departing from the broader spirit and scope as set forth in the claims. Thus, although certain embodiments have been described, such embodiments are not intended to be limiting. Various modifications and equivalents are within the scope of the following claims.

100: Artificial Reality System Environment 110: Console 112: App store 114:Headphone Tracking Module 116: Artificial Reality Engine 118:Eye Tracking Module 120: near-eye display 122: display electronics 124: Display optics 126: Locator 128: Position sensor 130:Eye Tracking Unit 132: Inertial measurement unit 140: input/output interface 150: external imaging device 200: HMD device 220: subject 223: bottom side 225: front side 227: left side 230: head strap 300: near-eye display 305: frame 310: Display 330: illuminator 340: high resolution camera 350a: sensor 350b: sensor 350c: sensor 350d: sensor 350e: sensor 400: Augmented Reality System 410: Projector 412: image source 414: Projector optics 415: Combiner 420: Substrate 430: Input coupler 440: output coupler 450: light 460: extracted light 490: eyes 495: eye socket 500: near-eye display device 510: light source 512: red light emitter 514: Green emitter 516:Blue light emitter 520: Projection optics 530: waveguide display 532:Coupler 540: light source 542: red light emitter 544: Green emitter 546:Blue light emitter 550: Near-eye display device 560: Freeform Optics 570: Scan mirror 580:Waveguide display 582:Coupler 590: eyes 600: near eye display system 610: image source assembly 620: controller 630: image processor 640: display panel 642: light source 644: Driver circuit 650: Projector 700:VCSEL 705: Tunable VCSEL 710: Substrate 712: drive circuit 720:Block DBR 722:VCSEL 724:First reflector 726: active area 730: Bottom DBR 732: first electrode 734: second electrode 740: cladding layer 750: active zone 752:Second reflector 760: cladding layer 762: MEMS Devices 770: top DBR 810:Pump photons 815:Virtual excited state 820: Photon 830: Photon 900: structure 902: structure 904: structure 910: Optical Resonator 920: Coupling structure 930: Optical Resonator 940:Pump waveguide 950: output waveguide 960: Optical Resonators 970: waveguide 980: waveguide 1000: visible light source 1010: drive circuit 1020:VCSEL 1022: first reflector 1024: active area 1026: Partial reflector 1028: Polarizer 1030: the first electrode 1032: second electrode 1040: microresonator 1042: Coupling structure 1050: second reflector 1060: Dielectric material 1100: visible light source 1110: drive circuit 1120:VCSEL 1122: first reflector 1124: active area 1130: second reflector 1140: first electrode 1142: second electrode 1150: microresonator 1152: Coupling structure 1160: Dielectric material 1200: visible light source 1202: visible light source 1210: drive circuit 1220:VCSEL 1222:First reflector 1224: active area 1230: second reflector 1240: first electrode 1242: second electrode 1250: waveguide 1252: Coupling structure 1260: microresonator 1262: Microresonator 1270: Dielectric material 1300: visible light source 1302: visible light source 1310: drive circuit 1320:VCSEL 1322:First reflector 1324: active area 1326: Partial reflector 1328: Polarizer 1330: Second reflector 1340: first electrode 1342: second electrode 1350: waveguide 1352: Input coupling structure 1360: Dielectric material 1370: Microresonator 1372: Microresonator 1400: visible light source array 1402: blue light source 1404: Green light source 1406: red light source 1410: drive circuit 1420:VCSEL 1422: First reflector 1424: active zone 1430: first electrode 1432: second electrode 1440: Microresonator 1442: Microresonator 1444: Microresonator 1450: Coupling structure 1452: Coupling structure 1454: Coupling structure 1460: Second reflector 1462:Second reflector 1464:Second reflector 1500: visible light source array 1502: visible light source 1510: drive circuit 1520:VCSEL 1522: First reflector 1524: active zone 1526: Partial reflector 1528: Polarizer 1530: Second reflector 1540: first electrode 1542: second electrode 1550: First microresonator 1552: Coupling structure 1560: Second microresonator 1562: Coupling Structure 1570: The third microresonator 1572: Coupling structure 1600: visible light source array 1602: visible light source 1610: drive circuit 1620:VCSEL 1622: First reflector 1624: active area 1626: Partial reflector 1628: Polarizer 1630: Second reflector 1640: first electrode 1642: second electrode 1650: First microresonator 1652: Coupling Structure 1660: Second Microresonator 1662: Coupling Structures 1670: The third microresonator 1672: Coupling Structure 1690: electrode 1692: electrode 1694: electrode 1700: visible light source 1710: drive circuit 1720:VCSEL 1722: First reflector 1724: active zone 1726: Partial reflector 1728: Polarizer 1730: first electrode 1732: second electrode 1740: Microresonators 1742: Coupling structure 1750: Second reflector 1770: MEMS devices 1780: curve 1790: signal light 1792: signal light 1794: signal light 1800: Array of Visible Light Sources 1802: Visible light source 1810: Drive circuit 1820:VCSEL 1822: First reflector 1824: active zone 1826: Partial reflector 1828: Polarizer 1830: Second reflector 1832: MEMS devices 1840: First electrode 1842: Second electrode 1850: First microresonator 1852: Coupled Structures 1860: Second microresonator 1862: Coupled Structures 1870: The third microresonator 1872: Coupled Structures 1890: Electrodes 1892: Electrodes 1894: Electrodes 1900: Electronic systems 1910: Processor 1920: Memory 1922: Application modules 1924: Application Mods 1925: Operating system 1926: Virtual reality engine 1930: Wireless Communication Subsystem 1932: Wireless Links 1934: Antenna 1940: Busbar 1950: Camera 1960:Display module 1970: User input/output modules 1980: Other hardware mods 1990: Sensors x: direction y: direction z: direction

Illustrative specific examples are described in detail below with reference to the following figures. [ FIG. 1 ] is a simplified block diagram of an example of an artificial reality system environment including a near-eye display, according to certain embodiments. [ Fig. 2 ] is a perspective view of an example of a near-eye display in the form of a head-mounted display (HMD) device for implementing some of the examples disclosed herein. [ FIG. 3 ] Is a perspective view of an example of a near-eye display in the form of a pair of glasses for implementing some of the examples disclosed herein. [ FIG. 4 ] Illustrates an example of an optical see-through augmented reality system including a waveguide display according to certain embodiments. [ FIG. 5A ] Illustrates an example of a near-eye display device including a waveguide display according to some embodiments. [ FIG. 5B ] Illustrates an example of a near-eye display device including a waveguide display according to some embodiments. [ FIG. 6 ] illustrates an example of an image source assembly in an augmented reality system according to some embodiments. [FIG. 7A] An example of a vertical cavity surface emitting laser (VCSEL) is illustrated. [FIG. 7B] Illustrates an example of a tunable VCSEL according to certain embodiments. [ FIGS. 8A and 8B ] illustrate an example of generating a higher frequency optical signal through degenerate four-wave mixing using lower frequency pump light. [FIG. 8C] Multiple longitudinal resonance modes illustrating an example of a microresonator. [ FIG. 9A ] Shows a cross-sectional view of an example of a coupling structure configured to vertically couple light generated in an optical resonator out of the optical resonator, according to certain embodiments. [ FIG. [ FIG. 9B ] A top view showing an example of the coupling structure of FIG. 9A according to some embodiments. [ FIG. 9C ] A top view illustrating an example of a structure configured to couple light generated in an optical resonator into an output waveguide, according to certain embodiments. [ FIG. 9D ] A top view illustrating another example of a structure configured to couple light generated in an optical resonator into an output waveguide, according to certain embodiments. [ FIGS. 10A and 10B ] illustrate an example of a visible light source of a microresonator included in a vertical cavity and directly pumped by an infrared light VCSEL in the vertical cavity, according to some embodiments, wherein the Visible light is coupled vertically out of the vertical cavity. [ FIG. 11A ] Illustrates an example of a visible light source including a microresonator outside a vertical cavity and directly pumped by an infrared light VCSEL, according to certain embodiments. [FIG. 11B] A plan view illustrating an example of the visible light source of FIG. 11A. [FIGS. 12A and 12B] illustrates an example of a visible light source comprising a microresonator pumped by an infrared light VCSEL, wherein infrared light is coupled to in the microresonator. [FIGS. 12C and 12D] illustrates an example of a visible light source comprising a microresonator pumped by an infrared light VCSEL through in-coupling structures and waveguides coupling to the microresonator on different vertical layers, according to certain embodiments into the microresonator. [FIG. 13A] illustrates an example of a visible light source including a microresonator pumped by an infrared light VCSEL in a vertical cavity through an in-coupling structure in the vertical cavity and in the same state as the microresonator, according to some embodiments. The waveguides on the vertical layers are coupled into the microresonators. [FIG. 13B] A plan view illustrating an example of the visible light source of FIG. 13A. [FIG. 13C] Illustrates an example of a visible light source including a microresonator pumped by an infrared light VCSEL in a vertical cavity through an in-coupling structure in the vertical cavity and at a different distance from the microresonator, according to some embodiments. The waveguides on the vertical layers are coupled into the microresonators. [FIG. 13D] A top view illustrating an example of the visible light source of FIG. 13C. [FIG. 14A] Illustrates an example of an array of visible light sources configured to emit different colors of visible light, wherein each visible light source in the array is included in a vertical cavity and is directly pumped by an infrared light VCSEL in the vertical cavity, according to certain embodiments Pu's microresonator, and the visible light generated in the microresonator is vertically coupled out of the vertical cavity. [FIGS. 14B and 14C] Top views illustrating an example of the visible light source array of FIG. 14A. [FIG. 15A] Illustrates an example of an array of visible light sources according to certain embodiments, wherein each visible light source in the array is configured to generate visible light of a different color. [FIG. 15B] A top view illustrating an example of the visible light source array of FIG. 15A. [ FIG. 16A ] Illustrates an example of an array of visible light sources according to certain embodiments, wherein each visible light source is configured to emit visible light in multiple colors and the respective intensity of visible light in each color can be individually controlled. [FIG. 16B] A top view illustrating an example of the visible light source array of FIG. 16A. [ FIG. 17A ] Illustrates an example of a visible light source that can be tuned to emit different colors of visible light, according to certain embodiments. [FIG. 17B] A top view illustrating an example of the visible light source array of FIG. 17A. [ FIGS. 17C and 17D ] illustrates an example of generating visible light of different colors by tuning the visible light source of FIGS. 17A and 17B . [ FIG. 18A ] Illustrates an example of an array of visible light sources according to certain embodiments, wherein each visible light source is tuneable to emit visible light in one or more colors and the respective intensity of visible light in each color is individually controllable. [FIG. 18B] A top view illustrating an example of the visible light source array of FIG. 18A. [ FIG. 19 ] is a simplified block diagram of an electronic system of an example of a near-eye display according to some embodiments. The drawings depict specific examples of the invention for purposes of illustration only. Those of ordinary skill in the art will readily recognize from the following description that alternative embodiments of the structures and methods described may be employed without departing from the principles of the invention or what is claimed. In the figures, similar components and/or features may have the same reference label. Further, various components of the same type can be distinguished by following the reference label by a dash and a second label that distinguishes among similar components. If only a first reference sign is used in this description, this description applies to any of similar components having the same first reference sign independent of the second reference sign.

1000: visible light source

1010: drive circuit

1020:VCSEL

1022: first reflector

1024: active area

1026: Partial reflector

1028: Polarizer

1030: the first electrode

1032: second electrode

1040: microresonator

1042: Coupling structure

1050: second reflector

1060: Dielectric material

Claims (20)

A visible light source comprising: Substrate; A vertical cavity surface-emitting laser on the substrate and comprising: an active semiconductor region configured to emit infrared light; and a first reflector configured to reflect the infrared light emitted by the active semiconductor region; a second reflector configured to reflect the infrared light, the first reflector and the second reflector forming a vertical cavity for the infrared light; one or more microresonators on the substrate and configured to receive the infrared light and use the infrared light to produce visible light of one or more colors via optical parameter oscillation; and One or more output couplers configured to couple the visible light of one or more colors from the one or more microresonators into free space or into a photonic integrated circuit. Such as the visible light source of claim 1, wherein: the one or more microresonators include a first microresonator and a second microresonator arranged vertically relative to each other; and The first microresonator and the second microresonator are characterized by different sizes, different shapes, different materials, or combinations thereof, and are configured to generate visible light of different distinct colors. Such as the visible light source of claim 2, which further includes: a first tuning circuit configured to tune the first microresonator to control the intensity of the visible light generated by the first microresonator; and A second tuning circuit configured to tune the second microresonator to control the intensity of the visible light generated by the second microresonator. The visible light source as claimed in claim 1, further comprising a microactuator configured to move the second reflector to change the optical path length of the vertical cavity and thus change the light emitted by the active semiconductor region A wavelength of infrared light, wherein a microresonator of the one or more microresonators is configured to: generating visible light of a first color using infrared light of a first wavelength; and Visible light of a second color is generated using infrared light of a second wavelength. Such as the visible light source of claim 1, wherein: the one or more microresonators are located in or on the vertical cavity; and Each of the one or more microresonators is configured to receive the infrared light emitted by the active semiconductor region directly or via an input coupler. The visible light source of claim 1, wherein each of the one or more output couplers comprises a grating coupler, a dielectric diffuser, a metallic diffuser, or a nanoresonator. The visible light source of claim 6, wherein the grating coupler is tilted, apodized, chirped or a combination thereof. The visible light source of claim 1, wherein the one or more microresonators are configured to generate the visible light via degenerate four-wave mixing (DFWM). Such as the visible light source of claim 1, wherein: at least one of the one or more microresonators is located outside the vertical cavity and out of alignment with the vertical cavity surface-emitting laser; and The visible light source further comprises: a waveguide optically coupled to the at least one microresonator; and an input coupler in or on top of the vertical cavity and configured to couple the infrared light emitted by the active semiconductor region into the waveguide. The visible light source of claim 1, wherein each of the first reflector and the second reflector comprises a high-contrast grating or a distributed Bragg (Bragg) reflector, the distributed Bragg reflector comprising a dielectric layer, semiconducting layer or both. The visible light source of claim 1, wherein the second reflector is anti-reflection for the visible light. The visible light source of claim 1, wherein the one or more microresonators comprise at least one of a microring, a microdisk, a waveguide-based cavity, a photonic crystal point defect cavity, a photonic crystal ring cavity, or a plasmonic resonator . The visible light source of claim 1, wherein the one or more microresonators are characterized by a circular ring shape, an elliptical ring shape, a spiral shape, or a track shape. The visible light source of claim 1, wherein the one or more output couplers are configured to vertically couple the visible light into free space or couple the visible light into a photonic integrated circuit. Such as the visible light source of claim 1, which further includes: a third reflector located in the vertical cavity, wherein the third reflector is partially reflective to the infrared light; a polarizing component located in the vertical cavity and configured to select a polarization mode of the infrared light; or Both the third reflector and the polarizing component. The visible light source according to claim 15, wherein the polarizing component comprises a polarizer, a wave plate, a spatially varying polarizer or a spatially varying wave plate. A visible light source array comprising: a substrate including drive circuitry formed thereon; and a die or wafer that is directly or indirectly bonded to the drive circuit, the die or wafer including an array of visible light sources formed thereon, wherein each visible light source in the array of visible light sources can be driven by the Circuits are individually addressed and contain: a vertical cavity formed by a first reflector and a second reflector configured to reflect infrared light; an active region located in the vertical cavity and configured to emit infrared light; one or more microresonators configured to receive the infrared light and use the infrared light to produce visible light of one or more colors via optical parameter oscillation; and One or more output couplers configured to couple the visible light of one or more colors from the one or more microresonators into free space or into one or more waveguides. The visible light source array of claim 17, wherein each visible light source in the visible light source array further comprises one or more tuning circuits configured to tune the one or more microresonators to control The respective intensities of the visible light exhibiting each of the one or more colors. The visible light source array of claim 17, wherein: Each visible light source in the array of visible light sources further includes a microactuator configured to move the second reflector to change the optical path length of the vertical cavity and thereby change the the wavelength of infrared light; and A microresonator of the one or more microresonators is configured to: generating visible light of a first color using infrared light of a first wavelength; and Visible light of a second color is generated using infrared light of a second wavelength. A visible light source array comprising: a substrate including drive circuitry formed thereon; and a die or wafer that is directly or indirectly bonded to the drive circuit, the die or wafer including an array of visible light sources formed thereon, wherein each visible light source in the array of visible light sources can be driven by the Circuits are individually addressed and contain: a vertical cavity formed by a first reflector and a second reflector configured to reflect infrared light; an active region located in the vertical cavity and configured to emit infrared light; a microresonator configured to receive the infrared light and use the infrared light to generate visible light via optical parameter oscillation; and an output coupler configured to couple the visible light from the microresonator into free space or a waveguide, Wherein the first microresonator in the first visible light source in the visible light source array and the second microresonator in the second visible light source in the visible light source array have different sizes, different shapes, different materials or combinations thereof, And configured to produce visible light of different colors.

Images