PATENT DOCUMENT

Publication Number: US-11914141-B1
Application Number: US-201916455416-A
Country: US
Kind Code: B1

Title: Electronic device with protected light sources

Abstract:
An electronic device such as a head-mounted device may have gaze tracking sensors and other circuits that include packaged light-emitting devices. The packaged light-emitting devices may each include a light-emitting component such as a light-emitting diode or laser that emits infrared light or light of other wavelengths. The packaged light-emitting devices may have protection circuitry. The protection circuitry of each device may include one or more sensors such as a package integrity sensor, a proximity sensor, a photodetector for measuring emitted light intensity, a temperature sensor for measuring a temperature associated with the light-emitting component, and a current sensor. A control circuit such as an integrated circuit containing a comparator or other analog circuitry and/or a digital control circuit may gather information from one or more of the sensors and may control the light-emitting component based on the sensor information to prevent elevated light emission intensities.

Claims:
What is claimed is: 
     
       1. A head-mounted device, comprising:
 a head-mounted support structure; 
 a display; 
 control circuitry configured to supply content using the display; and 
 a packaged light-emitting device operated by the control circuitry, wherein the packaged light-emitting device comprises:
 a package body that has first and second ends with electrical contacts on an exterior of the packaged light-emitting device, wherein the electrical contacts include first and second contacts on the first end and a third contact on the second end and wherein the first, second, and third contacts comprise at least first and second power supply contacts configured to receive power at respective first and second different power supply voltages; 
 a cover attached to the package body; 
 a light-emitting component configured to emit light through the cover; and 
 a sensor configured to provide information based on which the light-emitting component is controlled. 
 
 
     
     
       2. The head-mounted device defined in  claim 1 , wherein the head-mounted device comprises a gaze tracker system, wherein the gaze tracker system includes the packaged light-emitting device and includes an image sensor, wherein the light-emitting component comprises an infrared light-emitting diode configured to emit infrared light towards an eye box, and wherein the sensor comprises a photodetector configured to measure the emitted infrared light. 
     
     
       3. The head-mounted device defined in  claim 1  further comprising a gaze tracker system, wherein the gaze tracker system includes the light-emitting component and wherein the light-emitting component is configured to emit infrared light. 
     
     
       4. The head-mounted device defined in  claim 3  wherein the sensor comprises a package integrity sensor configured to detect removal of the cover. 
     
     
       5. The head-mounted device defined in  claim 4  wherein the packaged light-emitting device further comprises adhesive that attaches the cover to the package body and wherein the package integrity sensor comprises a signal path that passes the adhesive. 
     
     
       6. The head-mounted device defined in  claim 4  wherein the package integrity sensor comprises a capacitive sensor. 
     
     
       7. The head-mounted device defined in  claim 3  wherein the sensor comprises a capacitive proximity sensor. 
     
     
       8. The head-mounted device defined in  claim 3  wherein the sensor is configured to measure current flow through the light-emitting component. 
     
     
       9. The head-mounted device defined in  claim 3  wherein the light-emitting component has a temperature and wherein the sensor comprises a temperature sensor configured to measure the temperature. 
     
     
       10. The head-mounted device defined in  claim 3  wherein an exterior surface of the package body is colored with a warning and wherein the warning comprises a warning selected from the group consisting of: a non-neutral color serving as a warning, warning text, and a warning icon. 
     
     
       11. The head-mounted device defined in  claim 3  wherein the packaged light-emitting device further comprises a fuse coupled in series with the light-emitting component. 
     
     
       12. The head-mounted device defined in  claim 3  wherein the packaged light-emitting device further comprises a switch coupled in series with the light-emitting component and wherein a control circuit is configured to control the light-emitting component by controlling the switch based on the information from the sensor. 
     
     
       13. A packaged light-emitting device, comprising:
 a package body having an exterior surface with solder pads; 
 a cover coupled to the package body, wherein the cover has a non-linear light transmission versus light intensity characteristic; 
 an infrared light-emitting component configured to emit infrared light through the cover; 
 a control circuit that receives sensor output and that supplies a corresponding output signal; and 
 a switch coupled in series with the infrared light-emitting component, wherein the control circuit controls the switch using the output signal. 
 
     
     
       14. The packaged light-emitting device defined in  claim 13  wherein the control circuit comprises a comparator having an output that supplies the output signal, wherein the packaged light-emitting device further comprises a sensor that supplies the sensor output, and wherein the sensor comprises a sensor selected from the group consisting of: a temperature sensor, a current sensor, a photodetector, a proximity detector, and a package integrity sensor.

Description:
This application claims the benefit of provisional patent application No. 62/721,744, filed Aug. 23, 2018, which is hereby incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     This relates generally to electronic devices and, more particularly, to wearable electronic device systems. 
     Electronic devices are sometimes configured to be worn by users. For example, head-mounted devices are provided with head-mounted structures that allow the devices to be worn on users&#39; heads. The head-mounted devices may include optical systems. The optical systems may include light sources that emit light. 
     It can be challenging to produce optical systems with light sources for use in head-mounted devices. Head-mounted devices may have a variety of configurations, which may entail changes to the optical systems. These changes may affect the operation of the light sources. If care is not taken, the process of designing and qualifying these systems can consume more resources than desired. 
     SUMMARY 
     An electronic device such as a head-mounted device may have gaze tracking sensors and other devices that emit light. A gaze tracking sensor or other device may, for example, include one or more packaged light-emitting devices soldered to a printed circuit. These light-emitting devices may include a light-emitting component such as a light-emitting diode or laser that emits infrared light or light of other wavelengths. To ease the process of designing and qualifying optical systems with light sources for electronic devices such as head-mounted devices, packaged light-emitting devices may be provided with protection circuitry that enhances light emission safety. 
     The protection circuitry of a packaged light-emitting device may include one or more sensors such as a package integrity sensor, a proximity sensor, a photodetector for measuring emitted light intensity, a temperature sensor for measuring a temperature associated with the light-emitting component, and a current sensor. The package integrity sensor may be used to detect when a cover of the packaged light-emitting device has been removed. The proximity sensor may detect when an external object such as a user&#39;s eye is in proximity to the light-emitting device. The photodetector may be configured to measure a portion of the emitted light that is reflected from a coating on an inner surface of the cover to monitor for elevated light emission from the light-emitting component. The temperature sensor may be thermally coupled to the light-emitting component. If the light-emitting component is emitting an elevated amount of light, the temperature of the light-emitting component may be elevated. The temperature sensor may therefore be used in monitoring for elevated light emission from the light-emitting component. A current sensor in a protection circuit may also be used in detecting potentially elevated light emission. 
     The packaged light-emitting device may have a control circuit. The control circuit may be an integrated circuit containing a comparator or other analog circuitry and/or a digital control circuit. During operation of the electronic device, the control circuit in the packaged light-emitting device may gather information from one or more of the sensors in the packaged light-emitting device and may control the light-emitting component based on the sensor information to prevent elevated light emission intensities. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic diagram of an illustrative electronic device such as a head-mounted display device in accordance with an embodiment. 
         FIG.  2    is a top view of an illustrative head-mounted device in accordance with an embodiment. 
         FIG.  3    is a cross-sectional side view of a light source for a head-mounted device in accordance with an embodiment. 
         FIG.  4    is a bottom view of an illustrative light source showing a pattern of contacts that may be used to handle power and data signals in accordance with an embodiment. 
         FIG.  5    is a circuit diagram of illustrative packaged light-emitting device circuitry in accordance with an embodiment. 
         FIG.  6    is a cross-sectional side view of an illustrative capacitive sensor configured to detect the presence of a cover on a light source package in accordance with an embodiment. 
         FIG.  7    is cross-sectional side view of an illustrative capacitive sensor configured to detect presence of a body part of a user or other external object in the vicinity of a light source in accordance with an embodiment. 
         FIG.  8    is a diagram of an illustrative analog protection circuit in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic devices may include displays and other components for presenting content to users. The electronic devices may be wearable electronic devices. A wearable electronic device such as a head-mounted device may have head-mounted support structures that allow the head-mounted device to be worn on a user&#39;s head. 
     A head-mounted device may contain light sources. For example, a head-mounted device may have sensors such as gaze tracking sensors that emit infrared light beams towards a user&#39;s eyes. The gaze tracking sensors may monitor a user&#39;s eyes to detect the user&#39;s direction of gaze, eye position, and pupil size. Light sources may also be used in forming proximity sensors, distance sensors, gesture sensors, three-dimensional image sensors, and other input-output devices. 
     To help facilitate the development and qualification of head-mounted devices and to enhance safety, light sources can be provided with features that, in a self-contained fashion, limit user exposure to emitted light. These light sources, after testing to ensure regulatory compliance and compliance with other safety criteria, can be incorporated into a variety of different types of head-mounted device, thereby streamlining device development across different platforms. 
     A schematic diagram of an illustrative system having an electronic device with one or more light sources with protection circuitry is shown in  FIG.  1   . As shown in  FIG.  1   , system  8  may include one or more electronic devices such as electronic device  10 . The electronic devices of system  8  may include computers, cellular telephones, head-mounted devices, wristwatch devices, and other electronic devices. Configurations in which electronic device  10  is a head-mounted device are sometimes described herein as an example. 
     As shown in  FIG.  1   , electronic devices such as electronic device  10  may have control circuitry  12 . Control circuitry  12  may include storage and processing circuitry for controlling the operation of device  10 . Circuitry  12  may include storage such as hard disk drive storage, nonvolatile memory (e.g., electrically-programmable-read-only memory configured to form a solid-state drive), volatile memory (e.g., static or dynamic random-access-memory), etc. Processing circuitry in control circuitry  12  may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processors, power management units, audio chips, graphics processing units, application specific integrated circuits, and other integrated circuits. Software code may be stored on storage in circuitry  12  and run on processing circuitry in circuitry  12  to implement control operations for device  10  (e.g., data gathering operations, operations involved in processing three-dimensional facial image data, operations involving the adjustment of components using control signals, etc.). Control circuitry  12  may include wired and wireless communications circuitry. For example, control circuitry  12  may include radio-frequency transceiver circuitry such as cellular telephone transceiver circuitry, wireless local area network (WiFi®) transceiver circuitry, millimeter wave transceiver circuitry, and/or other wireless communications circuitry. 
     During operation, the communications circuitry of the devices in system  8  (e.g., the communications circuitry of control circuitry  12  of device  10 ), may be used to support communication between the electronic devices. For example, one electronic device may transmit video and/or audio data to another electronic device in system  8 . Electronic devices in system  8  may use wired and/or wireless communications circuitry to communicate through one or more communications networks (e.g., the Internet, local area networks, etc.). The communications circuitry may be used to allow data to be received by device  10  from external equipment (e.g., a tethered computer, a portable device such as a handheld device or laptop computer, online computing equipment such as a remote server or other remote computing equipment, or other electrical equipment) and/or to provide data to external equipment. 
     Device  10  may include input-output devices  22 . Input-output devices  22  may be used to allow a user to provide device  10  with user input. Input-output devices  22  may also be used to gather information on the environment in which device  10  is operating. Output components in devices  22  may allow device  10  to provide a user with output and may be used to communicate with external electrical equipment. 
     As shown in  FIG.  1   , input-output devices  22  may include one or more displays such as display  14 . In some configurations, display  14  of device  10  includes left and right display panels (sometimes referred to as left and right portions of display  14  and/or left and right displays) that are in alignment with the user&#39;s left and right eyes, respectively. In other configurations, display  14  includes a single display panel that extends across both eyes. Display  14  may be used to display images. The visual content that is displayed on display  14  may be viewed by a user of device  10 . Optical systems that include lenses and other components may be used to allow a user with eyes located in eye boxes to view the content on display  14 . 
     Displays in device  10  such as display  14  may be organic light-emitting diode displays or other displays based on arrays of light-emitting diodes, liquid crystal displays, liquid-crystal-on-silicon displays, projectors or displays based on projecting light beams on a surface directly or indirectly through specialized optics (e.g., digital micromirror devices), electrophoretic displays, plasma displays, electrowetting displays, or any other suitable displays. 
     Display  14  may present computer-generated content such as virtual reality content and mixed reality content to a user. Virtual reality content may be displayed in the absence of real-world content. Mixed reality content, which may sometimes be referred to as augmented reality content, may include computer-generated images that are overlaid on real-world images. The real-world images may be captured by a camera (e.g., a forward-facing camera) and merged with overlaid computer-generated content or an optical coupling system may be used to allow computer-generated content to be overlaid on top of real-world images. As an example, a pair of mixed reality glasses or other augmented reality head-mounted display may include a display device that provides images to a user through a beam splitter, prism, holographic coupler, or other optical coupler. 
     Input-output circuitry  22  may include sensors  16 . Sensors  16  may include, for example, three-dimensional sensors (e.g., three-dimensional image sensors such as structured light sensors that emit beams of light and that use two-dimensional digital image sensors to gather image data for three-dimensional images from light spots that are produced when a target is illuminated by the beams of light), binocular three-dimensional image sensors that gather three-dimensional images using two or more cameras in a binocular imaging arrangement, three-dimensional lidar (light detection and ranging) sensors, three-dimensional radio-frequency sensors, or other sensors that gather three-dimensional image data), cameras (e.g., infrared and/or visible digital image sensors), touch sensors, buttons, force sensors, sensors such as contact sensors based on switches, gas sensors, pressure sensors, moisture sensors, magnetic sensors, audio sensors (microphones), ambient light sensors, microphones for gathering voice commands and other audio input, sensors that are configured to gather information on motion, position, and/or orientation (e.g., accelerometers, gyroscopes, compasses, and/or inertial measurement units that include all of these sensors or a subset of one or two of these sensors), fingerprint sensors and other biometric sensors, optical position sensors (optical encoders), and/or other position sensors such as linear position sensors, proximity sensors (e.g., capacitive proximity sensors, optical proximity sensors, ultrasonic proximity sensors, and/or other proximity sensors), and/or other sensors. 
     As shown in  FIG.  1   , sensors  16  may include gaze tracking sensors  20 . Gaze tracking sensors  20 , which may sometimes be referred to as gaze tracking systems, gaze trackers, gaze detectors, or gaze tracker systems, may include light-emitting devices  30 . Devices  30 , which may sometimes be referred to as light sources or packaged light-emitting devices, may emit beams of light onto a user&#39;s eyes. Devices  30  may, for example, include infrared light-emitting diodes and/or infrared lasers (e.g., vertical cavity laser diodes or other laser diodes) that emit infrared light that is invisible to a user. The beams of light reflect from the user&#39;s eyes and can be imaged using image sensors  32 . Sensors  20  may, as an example, include a left-eye gaze tracking sensor  20  that has a left infrared digital image sensor that detects reflected light from multiple beams of light directed towards the user&#39;s left eye through a left lens in device  10  and a right infrared digital image sensor that detects reflected light from multiple beams of light directed toward the user&#39;s right eye through a right lens in device  20 . By processing the pattern of reflected light beams that is sensed using the image sensors, the positions of the user&#39;s eyes, pupil size, and the direction of view of each eye can be monitored in real time. This allows device  10  to perform functions such as foveated image rendering for display  14 , wakefulness detection and other user monitoring operations, and other operations involving eye information. 
     User input and other information may be gathered using sensors and other input devices in input-output devices  22 . If desired, input-output devices  22  may include other devices  24  such as haptic output devices (e.g., vibrating components), light-emitting diodes and other light sources, speakers such as ear speakers for producing audio output, and other electrical components. Device  10  may include circuits for receiving wireless power, circuits for transmitting power wirelessly to other devices, batteries and other energy storage devices (e.g., capacitors), joysticks, buttons, and/or other components. 
     Electronic device  10  may have housing structures (e.g., housing walls, straps, etc.), as shown by illustrative support structures  26  of  FIG.  1   . In configurations in which electronic device  10  is a head-mounted device (e.g., a pair of glasses, goggles, a helmet, a hat, etc.), support structures  26  may include head-mounted support structures (e.g., a helmet housing, head straps, temples in a pair of eyeglasses, goggle housing structures, and/or other head-mounted structures). The head-mounted support structures may be configured to be worn on a head of a user during operation of device  10  and may support display(s)  14 , sensors  16 , other components  24 , other input-output devices  22 , and control circuitry  12 . 
       FIG.  2    is a top view of electronic device  10  in an illustrative configuration in which electronic device  10  is a head-mounted device. As shown in  FIG.  2   , electronic device  10  may include support structures (see, e.g., support structures  26  of  FIG.  1   ) that are used in housing the components of device  10  and mounting device  10  onto a user&#39;s head. These support structures may include, for example, structures that form housing walls and other structures for main unit  26 - 2  (e.g., exterior housing walls, lens module structures and other support structures for optical components, etc.) and straps or other supplemental support structures such as structures  26 - 1  that help to hold main unit  26 - 2  on a user&#39;s face so that the user&#39;s eyes are located within eye boxes  60 . 
     Display  14  may include left and right display panels (e.g., left and right pixel arrays, sometimes referred to as left and right displays or left and right display portions). These pixel arrays may be mounted respectively in left and right display modules  70  corresponding respectively to a user&#39;s left eye (and left eye box  60 ) and right eye (and right eye box). Modules  70 , which may sometimes be referred to as lens support structures, lens housings, or lens and display housings, may, if desired, be individually positioned relative to the housing wall structures of main unit  26 - 2  and relative to a user&#39;s eyes using positioners. The positioners may include stepper motors, piezoelectric actuators, motors, linear electromagnetic actuators, and/or other electronic components for adjusting lens module positions. Positioners in device  10  may be controlled by control circuitry  12  during operation of device  10 . For example, positioners may be used to adjust the spacing between modules  70  (and therefore the lens-to-lens spacing between the left and right lenses of modules  70 ) to match the interpupillary distance IPD of a user&#39;s eyes. This allows the user to view the left and right display portions of display  14  in the left and right lens modules. 
     The positions of the user&#39;s eyes in eye boxes  60  and therefore interpupillary distance IPD may be measured using gaze tracking sensors  20 . There may be, for example, a respective gaze tracking sensor  20  in each lens module  70  or gaze tracking sensors may be mounted elsewhere in device  10 . Each gaze tracking sensor  20  may have one or more light-emitting devices  30  (sometimes referred to as light sources) for emitting beams of infrared light onto a user&#39;s eye in eye box  60  through lens  72  and may have an infrared image sensor  32  to capture an corresponding image of the user&#39;s eye when the user&#39;s eye is illuminated by the infrared light beam. The captured image may then be processed using processing circuitry. This allows the gaze tracking sensor  20  to identify the direction of gaze of the user&#39;s eye, the location of the user&#39;s pupil, and the size of the user&#39;s pupil. By using a gaze tracking sensor  20  in each lens module  70 , control circuitry  12  can measure the user&#39;s interpupillary distance IPD. 
     In addition to light-emitting devices  30  in gaze tracking sensors  20 , device  10  may include additional light sources such as camera flash light sources, flashlight light sources, proximity detector light sources (e.g., an infrared light source that emits light that is detected by an associated optical proximity sensor photodetector after reflection from an external object to sense proximity of the external object), optical distance and/or velocity sensors (e.g., light detection and ranging or LIDAR sensors, self-mixing sensors for determining distance and/or velocity, etc.), gesture sensors, structured light three-dimensional image sensors that detect three-dimensional images by monitoring distortion in a grid of emitted light beams, and/or other light-emitting components. These components may be implemented using light-emitting diodes (e.g., organic light-emitting diodes and/or light-emitting diodes formed from crystalline semiconductor dies), lasers (e.g., vertical cavity surface emitting diode lasers and/or other diode lasers), and/or other sources of light. The light emitted from devices  30  and the other light sources of device  10  may be visible light, ultraviolet light, infrared light, and/or combinations of visible, ultraviolet, and/or infrared light. To enhance user eye safety, light sources in device  10  such as light-emitting devices  30  and/or the other light sources of device  10  may be provided with protection circuitry. 
     During use of light-emitting devices  30  in gaze tracking sensors  20  and other components in device  10 , light may be emitted towards a user&#39;s eyes. To enhance eye safety, packaged light-emitting devices  30  may be provided with protection circuitry. An illustrative light-emitting device  30  with protection circuitry is shown in  FIG.  3   . As shown in  FIG.  3   , light-emitting device  30  may include electrical components  96 . Components  96  may include light-emitting components, control circuits, sensors, and other electrical devices. Components  96  may include discrete components, integrated circuits such as application-specific integrated circuits that are not programmable after hard coding, packaged and unpackaged components, and/or other components. Components  96  may be packaged within an electronic device package formed from package body  80  and package cover  102  or other package structures. Package body  80  may have a rear wall portion such as rear wall portion  82  and may have sidewall portions  84  (e.g., four sidewalls that help form a rectangular box shape for device  30 ) and/or package body  80  may have other configurations. 
     Package body  80  may be formed from polymer, glass, other dielectrics, metal and other conductors, and/or other materials and may include printed circuits, signal paths formed from metal traces, metal leads, and other conductive structures, and/or other package housing structures. Package cover  102  may be formed from a material such as glass, polymer, sapphire or other crystalline material, and/or other materials that are transparent to light emitted by a light-emitting component in components  96  in interior  106 . This allows emitted light  125  to pass through cover  102  from interior region (interior)  106  to exterior region (exterior)  108 . Cover  102  may cover some or all of the top of package body  80  and/or may cover other sides of package body  80 . Cover  102  forms a window that is transparent at the wavelength of light  125  and/or at other desired wavelengths. If desired, cover  102  may be formed from a material that exhibits a non-linear transmission as a function of the intensity of light  125  (e.g., a non-linear optical crystal, a polymer that sustains damage and develops haze and/or opacity when exposed to higher light intensities, and/or other materials with non-linear-transmission). For example, cover  102  may be formed from a material that is transparent at normal operating intensities but that exhibits decreased levels of transparency at elevated operating intensities. In response to elevated light output intensities, the transparency of this type of cover will decrease and prevent more of light  125  from escaping the interior of device  30  than desired. 
     To clearly identify device  30  and thereby prevent device  30  from inadvertently being installed in equipment for which device  30  was not intended, device  30  can be provided with visual identifying information such as information  105 . Information  105  may be a bar code, text, an icon, or a warning (e.g., an icon and/or text indicating that device  30  emits infrared light and/or that device  30  emits light with a certain maximum power), may have a predetermined color (e.g., a bright color such as orange, yellow, red, or other non-neutral color that helps indicate visually that device  30  is a light-emitting device), and/or may include other visually identifying information. This information may be provided over some or all of the exterior surface of body  80  and/or other portions of device  30 . Information  105  may be formed by printing (e.g., screen printing of ink, ink-jet printing, etc.), spray coating of ink, laser marking, deposition of other solid and/or patterned materials, or other suitable fabrication techniques. 
     The device package formed from body  80  may include interior contacts  90  and exterior contacts  88 . Contacts  88  and  90 , may sometimes be referred to as solder pads, may be formed from metal traces or other conductive structures on the surfaces of body  80  in interior  106  and exterior  108 , respectively. Contacts  90  may mate with corresponding contacts (solder pads) on electrical components  96  such as contacts (solder pads)  94 . Solder  92  may be used to form solder joints that couple contacts  94  to respective contacts  90 . If desired, conductive adhesive, welds, metal clips, spring-loaded pins, and/or other coupling structures may be used to couple the circuitry of components  96  to contacts  90 . 
     Exterior contacts  88  may be configured to allow device  30  to be mounted to a printed circuit. As shown in  FIG.  3   , for example, solder  89  or other conductive material (e.g., conductive adhesive) may be used to couple contacts  88  to corresponding printed circuit contacts  91  on a printed circuit formed from printed circuit substrate  93 . Other electrical components may also be soldered to the printed circuit and may be electrically interconnected with device  30  using metal traces forming signal paths in printed circuit substrate  93 . Substrate  93  may be formed from rigid printed circuit material (e.g., fiberglass-filled epoxy) and/or flexible printed circuit material (e.g., a flexible sheet of polyimide or a layer of other flexible printed circuit polymer material). 
     Signal paths  86  in device  30  may be formed from metal traces (e.g., patterned thin-film metal layers and/or vias), stamped metal foil, wires, wire-bonded wires, metal members, and/or other conductive structures. These conductive structures may be formed on interior and/or exterior surfaces of body  80  and/or may include structures that are embedded within body  80 . If desired, some of these signal paths may form a signal path such as signal path  98  that are used in detecting whether or not cover  102  has been removed. As shown in  FIG.  3   , trace  98  may have a portion such as portion  100  that passes adhesive layer  104  (e.g., by lying under adhesive  104 , by lying over adhesive  104 , and/or by passing through adhesive layer  104 ). Adhesive layer  104  may have a shape such as a ring shape that extends around the upper surface of sidewall portion  84  of body  80  and attaches cover  102  to body  80  to form the package for device  30 . In the event that cover  102  is removed after assembly, the signal path formed from portion  100  will be damaged and an open circuit will be created in path  98 . As a result, signal path  98  serves as a package integrity sensor that detects whether the device  30  (e.g., the package for device  30 ) has been opened. 
     A bottom view of device  30  of  FIG.  3    is shown in  FIG.  4   . To reduce the likelihood that device  30  is inadvertently mounted on a printed circuit in a system for which device  30  was not intended (and thereby prevent inadvertent powering of device  30  and a resulting potential for light emission), contacts  88  may have a contact assignment pattern that is unique (or nearly unique) to device  30 . A standard two-terminal light-emitting diode has first and second contacts at opposing ends of the light-emitting diode. This type of two-terminal light-emitting diode is therefore configured so that the first and second contacts will mate with and be soldered to corresponding first and second printed circuit board contacts  112  of  FIG.  4    and will receive first and second corresponding power supply voltages through those contacts  112 . In the illustrative configuration of device  30  of  FIG.  4   , in contrast, a first end of device  30  (e.g., a first end of body  80 ) has three contacts  88  and an opposing second end of device  30  (e.g., a second end of body  80 ) has three contacts  88 . On a printed circuit board that is properly configured to operate with device  30  such as printed circuit substrate  93  of  FIG.  3   , six printed circuit contacts  91  are provided using a first set of three contacts  91  and a seconds set of three contacts  91 . These six contacts  91  are configured to mate with contacts  88  without any of contacts  91  overlapping more than one of contacts  88  and without any of contacts  88  overlapping more than one of contacts  91 . 
     The contact assignments for contacts  88  may have a pattern that is incompatible with standard printed circuit contacts  112 . As a result, contacts  88  will only effectively provide power and other signals to device  30  when corresponding mating printed circuit contacts  91  are provided with an appropriate unique (or nearly unique) corresponding contact assignment pattern. In the example of  FIG.  4   , the first set of three contacts at the first end of device  30  includes positive (+) and negative (−) power supply contacts  88  on the outer sides of device  30 , that receive, respectively first and second different power supply voltages from mating printed circuit contacts  91 . The center contact  88  in the first set of three contacts may be coupled to a corresponding center printed circuit contact  91  and can be used for data, may be left floating, or may be coupled to the first or second power supply voltage or other suitable power supply voltage (as examples). The second set of three contacts at the second end of device  30  in the  FIG.  4    example includes three data contacts D. Data contacts D may be used for analog and/or digital signals other than power supply signals (as an example). With this type of arrangement for the contact assignments (pin assignments) for device  30 , it is not possible to inadvertently power device  30  by soldering device  30  to standard printed circuit contacts  112 . Device  30  will only be powered properly and will only operate when powered correctly using the first and second power supply voltages supplied to the outermost terminals in the first set of three contacts at the first end of device  30 . When device  30  is soldered to a printed circuit (e.g., printed circuit substrate  93  of  FIG.  3   ) that has a contact pattern and contact assignment pattern that matches the contact pattern and contact assignment pattern of device  30 , device  30  will be powered and can operate as part of device  10 . In the event that device  30  is inadvertently incorporated into an electronic device that has a contact pattern configured to power a standard two-terminal light-emitting diode, device  30  will not operate and will not emit light, thereby enhancing safety. 
       FIG.  5    shows illustrative circuitry that may be incorporated into device  30 . This circuitry may be formed using one or more packaged components and/or unpackaged components (e.g., bare semiconductor dies, etc.) such as one or more integrated circuits, discrete components, and/or other electrical components  96  of  FIG.  3   . The circuitry of  FIG.  5    may include protection circuitry with one or more sensors to enhance safety. 
     As shown in  FIG.  5   , device  30  includes a light source such as light source  120 . Light source  120  may include one or more light-emitting components such as light-emitting diodes and/or laser diodes. Configuration in which light source  120  includes a single light-emitting diode or laser diode are sometimes described herein as an example. Light source  120  may be configured to emit visible light, infrared light, and/or ultraviolet light. For example, light source  120  may be an infrared light-emitting diode or an infrared laser diode (e.g., a vertical cavity surface-emitting laser or other laser diode) that emits infrared light. During operation, emitted light  125  from light source  120  may pass through cover  102  (e.g., for use in gaze tracking sensor  20  or other circuitry in electronic device  10 ). 
     Control circuitry  150  may use one or more sensors to gather information on the status of device  30 . In the event that a safe operating state is detected, light source  120  may be allowed to operate normally and can be powered with a current that flows through light source  120  between first power supply terminal  124  (e.g., a positive power supply terminal) and second power supply terminal  126  (e.g., a ground power supply terminal). Fuse  128  may be interposed in series with light source  120  between terminals  124  and  126 . During normal operation, fuse  128  forms a closed circuit and allows current to be supplied to light source  120 . Control circuitry  150  can dynamically adjust the amount of current flowing through light source  120  and/or a fixed amount of current may flow through light source  120 , causing light source  120  to emit light  125 . If an elevated amount of current starts to flow through fuse  128 , fuse  128  will form an open circuit and will prevent current from flowing through light source  120 , thereby preventing emission of light  125 . Fuse  128  may be a passive component that is triggered (blown) by the level of current flowing through fuse  128  without additional external control. 
     If desired, overcurrent protection may also be provided using an electrically controlled overcurrent protection circuit such as overcurrent protection circuit  130 . Protection circuit  30  may be coupled in series with light source  120  between power supply terminals  124  and  126 . A current sensor in protection circuit  130  (e.g., a current sensor formed from a resistor coupled in series with source  120  and an associated voltage sensor that reads the voltage drop across the resistor) may inform control circuitry such as control circuit  150  in device  30  when an elevated amount of current is beginning to flow through circuit  130 . Circuit  150  can then respond by directing overcurrent protection circuit  130  to form an open circuit (e.g., circuit  150  can supply a control circuit that directs a switch within circuit  130  that is coupled in series with light source  120  to form an open circuit). This blocks current flow through light source  120  and prevents emission of light  125 . 
     Excessive temperature of light source  120  (which may be indicative of elevated current levels and elevated light emission by light source  120 ) may be detected using temperature sensor  122 . Temperature sensor  122  may be thermally coupled to light source  120 . Temperature measurements from sensor  122  may be gathered and processed by control circuit  150  during operation of device  30 . In response to receiving temperature information from sensor  122  that indicates that the temperature of light source  120  has exceeded a predetermined threshold value, control circuitry  150  may direct protection circuit  126  (e.g., a switch coupled in series between terminals  124  and  126  in series with light source  120 ) to form an open circuit and thereby block current flow through light source  120 . 
     Another sensor that may be included in device  30  is a light sensor such as photodetector  132 . Some of emitted light  125  such as emitted light  125 ′ may be detected by photodetector  132 . Light  125 ′ may, as an example, reflect from an inner surface of cover  120 . Reflection can be enhanced by coating some or all of a surface of cover  120  (e.g., an inner surface) with a reflective coating to form light reflector  129 . Light reflector  129  (or an uncoated portion of cover  120 ) may reflect light  125 ′ towards photodetector  132  as reflected light  127 , so that photodetector  132  can measure the magnitude of emitted light  125 . During normal operation, emitted light  125  will have a normal magnitude and reflected light  127  will have a corresponding normal magnitude. If an enhanced amount of emitted light  125  starts to be emitted by light source  120 , control circuit  150  will detect that the amount of emitted light that is measured by photodetector  132  has exceeded a predetermined threshold and will direct protection circuit  126  to form an open circuit in response. By blocking current flow through light source  120  in response to measuring with photodetector  132  that emitted light  125  has an elevated strength, elevated amounts of light emission are prevented. 
     To determine whether device  30  is adjacent to a user&#39;s eye or other body part, device  30  may have a sensor such as proximity sensor  134 . Proximity sensor  134  may be formed from a capacitive sensor or other proximity sensor detection circuitry (e.g., an optical proximity detector, an acoustic proximity detector, etc.) that detects when external objects are within a predetermined distance of device  30 . A capacitive sensor may also be used in detecting when cover  102  is present and when cover  102  is absent (e.g., a capacitive sensor may be used in forming a package integrity sensor for device  30 ). In response to detecting that cover  102  has been removed and/or in response to detecting that an external object is adjacent to device  30  (e.g., within a predetermined distance of light source  120  and/or other components of device  30 ), control circuit  150  may direct a switch (e.g., a switch in protection circuit  126 ) to block current flow through light source  120 . As described in connection with  FIG.  3   , control circuit  150  may also monitor the integrity of device  30  using path  98 . If cover  102  is removed, portion  100  of path  98  will be damaged and will form an open circuit and/or will otherwise exhibit a changed resistance. This change in portion  100  can be detected by control circuit  150  so that control circuit  150  can block current flow through light source  120  (e.g., by opening a switch in protection circuit  130 ). 
       FIGS.  6  and  7    show illustrative capacitive sensor circuitry that may be used in device  30 . Capacitive sensing circuitry for device  30  may include self-capacitance and/or mutual capacitance circuitry and may be formed using metal traces configured to form one or more electrodes that are adjacent to cover  102  and/or located elsewhere in device  30 . In the example of  FIG.  6   , cover  102  has an inner coating of metal such as metal layer  156  adjacent to capacitive sensor electrodes  152  in a capacitive sensor. Electrodes  152  may be formed under adhesive  104  and may be supported by a portion of body  80  or other support structure. If cover  102  is removed, metal layer  156  will no longer be in the vicinity of capacitive sensor electrodes  152  and the capacitance reading sensed by the capacitive sensor will change and be detected by control circuitry  150 . Control circuitry  150  can then use block current flow through light source  120  (e.g., by opening a switch in protection circuit  130 ). 
     In the example of  FIG.  7   , a capacitive sensor in device  30  has been formed from capacitive sensor electrodes  152  under a portion of cover  102  (e.g., a portion of cover  102  that overlaps adhesive  104  and that allows electrodes  152  to be supported on a surface of body  80  or other support structure). In the event that a user&#39;s body (e.g., a user&#39;s eye or finger) or other external object  106  is close to device  30  (e.g., when distance DIS between external object  160  and the capacitive sensor electrodes  152  of the capacitive sensor is less than a predetermined threshold value), control circuitry  150  can direct protection circuit  130  to block current flow through light source  120 . In general, a capacitive sensor in device  30  can be formed using capacitive sensor electrode structures (e.g., metal traces or other conductive structures) that are formed on cover  120 , on body  80 , and/or on other supporting structures in device  30 . A capacitive sensor for device  30  may include first electrode structures to detect cover removal and/or second electrode structures to detect the presence of an external object adjacent to cover  102  (and therefor adjacent to light source  120 ) and/or a capacitive sensor for device  30  may use one or more shared capacitive sensor electrodes to detect both cover removal and external object presence. Arrangements in which other sensors (optical, etc.) for detecting external object proximity (including touch) and/or cover removal or other loss of package integrity may also be used, if desired. 
     Control circuit  150  may include analog processing circuitry and/or digital processing circuitry. In some configurations, solely analog processing circuitry may be used. In the illustrative arrangement of  FIG.  8   , the control circuitry of device  30  includes analog circuitry such as comparator  184 . Protection circuit  130  may include switch  186  for controlling current flow through light source  120  and may include optional current sensor  187  for measuring current flow through light source  120 . Control circuit  150  may control the output of light source  120  by adjusting the state of switch  186  based on information from current sensor  187  and/or other sensors in device  30 . 
     Light source  120  of  FIG.  8    may be formed from a light-emitting diode or light-emitting laser diode coupled in series with switch  186  between power supply terminal  124  and power supply terminal  126 . Comparator  184  may be provided with a reference voltage Vref from a reference voltage source at terminal  182  and may receive a sensor output signal Vsense at terminal  180 . Signal Vsense may be provided by a cover presence sensor formed from path  98 , proximity sensor  134 , photodetector  132 , temperature sensor  122 , current sensor  187  in overcurrent protection circuit  130 , or other sensor in device  30 . 
     During normal operation, Vsense is less than Vref and the output of comparator  184  has a first value, directing switch  186  to close and allowing current flow through light source  120  between terminals  124  and  126 . In response to detection that Vsense has exceeded Vref (which serves as a threshold voltage), comparator  184  supplies a second value (e.g., a second value having a logic value that is opposite to that of the first value) at its output that directs switch  186  to open and block current flow through light source  120 . In the example of  FIG.  8   , the operations of control circuit  150  can be handled using an analog control circuit such as comparator  184 . If desired, other circuitry (e.g., digital and/or analog circuitry) can be used. 
     As described above, one aspect of the present technology is the gathering and use of user data such as data on a user&#39;s eyes gathered with gaze tracking sensors  20 . The present disclosure contemplates that in some instances, gathered user data may include personal information data that uniquely identifies or can be used to contact or locate a specific person. Such personal information data can include demographic data, location-based data, telephone numbers, email addresses, twitter ID&#39;s, home addresses, data or records relating to a user&#39;s health or level of fitness (e.g., vital signs measurements, medication information, exercise information), date of birth, facial information, or any other identifying or personal information. 
     The present disclosure recognizes that the use of such personal information data, in the present technology, can be used to the benefit of users. For example, the personal information data can be used to deliver targeted content that is of greater interest to the user. Accordingly, use of such personal information data enables users to calculated control of the delivered content. Further, other uses for personal information data that benefit the user are also contemplated by the present disclosure. For instance, health and fitness data may be used to provide insights into a user&#39;s general wellness, or may be used as positive feedback to individuals using technology to pursue wellness goals. 
     The present disclosure contemplates that the entities responsible for the collection, analysis, disclosure, transfer, storage, or other use of such personal information data will comply with well-established privacy policies and/or privacy practices. In particular, such entities should implement and consistently use privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining personal information data private and secure. Such policies should be easily accessible by users, and should be updated as the collection and/or use of data changes. Personal information from users should be collected for legitimate and reasonable uses of the entity and not shared or sold outside of those legitimate uses. Further, such collection/sharing should occur after receiving the informed consent of the users. Additionally, such entities should consider taking any needed steps for safeguarding and securing access to such personal information data and ensuring that others with access to the personal information data adhere to their privacy policies and procedures. Further, such entities can subject themselves to evaluation by third parties to certify their adherence to widely accepted privacy policies and practices. In addition, policies and practices should be adapted for the particular types of personal information data being collected and/or accessed and adapted to applicable laws and standards, including jurisdiction-specific considerations. For instance, in the United States, collection of or access to certain health data may be governed by federal and/or state laws, such as the Health Insurance Portability and Accountability Act (HIPAA), whereas health data in other countries may be subject to other regulations and policies and should be handled accordingly. Hence different privacy practices should be maintained for different personal data types in each country. 
     Despite the foregoing, the present disclosure also contemplates embodiments in which users selectively block the use of, or access to, personal information data. That is, the present disclosure contemplates that hardware and/or software elements can be provided to prevent or block access to such personal information data. For example, the present technology can be configured to allow users to select to “opt in” or “opt out” of participation in the collection of personal information data during registration for services or anytime thereafter. In another example, users can select not to provide one or more types of user data. In yet another example, users can select to limit the length of time user-specific data is maintained. In addition to providing “opt in” and “opt out” options, the present disclosure contemplates providing notifications relating to the access or use of personal information. For instance, a user may be notified upon downloading an application (“app”) that their personal information data will be accessed and then reminded again just before personal information data is accessed by the app. 
     Moreover, it is the intent of the present disclosure that personal information data should be managed and handled in a way to minimize risks of unintentional or unauthorized access or use. Risk can be minimized by limiting the collection of data and deleting data once it is no longer needed. In addition, and when applicable, including in certain health related applications, data de-identification can be used to protect a user&#39;s privacy. De-identification may be facilitated, when appropriate, by removing specific identifiers (e.g., date of birth, etc.), controlling the amount or specificity of data stored (e.g., collecting location data at a city level rather than at an address level), controlling how data is stored (e.g., aggregating data across users), and/or other methods. 
     Therefore, although the present disclosure broadly covers use of personal information data to implement one or more various disclosed embodiments, the present disclosure also contemplates that the various embodiments can also be implemented without the need for accessing such personal information data. That is, the various embodiments of the present technology are not rendered inoperable due to the lack of all or a portion of such personal information data. 
     The foregoing is merely illustrative and various modifications can be made to the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20190627
Publication Date: 20240227
Grant Date: 20240227
Priority Date: 20180823
Inventors: ROTHKOPF, FLETCHER R.
VANDYKE, James W.
Assignee: APPLE INC
CPC Classifications: [{"code": "G02B27/0093", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02B27/0101", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B27/0172", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/013", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06V40/18", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B27/0093", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02B27/0101", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/013", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B27/0172", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06V40/18", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B27/0093", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02B27/0101", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B27/0172", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/013", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06V40/18", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 90014722