PATENT DOCUMENT

Publication Number: US-10306350-B1
Application Number: US-201816043027-A
Country: US
Kind Code: B1

Title: Electronic device having transreflective optical sensors

Abstract:
An electronic device may include an optical proximity sensor system. The optical proximity sensor system may be a transreflective optical proximity sensor system having a light emitter that emits light into a light-emitting region and a light detector that detects light in a light-detecting region. Control circuitry in the device can use the transreflective optical proximity sensor system to detect objects in an object detection region formed where the light-emitting region and light-detecting region overlap. The electronic device may be a pair of headphones in which housing structures such as housing walls define ear cup cavities. Speakers may be provided in the ear cups of the headphones to provide sound to the ear cup cavities. The transreflective optical proximity sensor system can detect the presence of a user&#39;s ear in an ear cup cavity.

Claims:
What is claimed is: 
     
       1. An electronic device, comprising:
 housing structures that form a cavity that receives an ear of a user; 
 a speaker that supplies sound to the cavity; and 
 a transreflective optical proximity sensor system that detects the ear in the cavity, wherein the transreflective optical proximity sensor system comprises:
 a light emitter on a first side of the cavity that emits light into a light-emitting region; and 
 a light detector on an opposing second side of the cavity that detects light in a light-detecting region, wherein the light-emitting region and the light-detecting region overlap in an object detection region, wherein the cavity receives the ear of the user in the object detection region, and wherein the light emitter does not transmit light directly to the light detector when the ear of the user is not present. 
 
 
     
     
       2. The electronic device defined in  claim 1  wherein the light emitter comprises an infrared light emitter and wherein the light detector comprises an infrared light detector. 
     
     
       3. The electronic device defined in  claim 2  wherein the housing structures include a wall with an opening that is filled with infrared-transparent window material overlapping the infrared light emitter. 
     
     
       4. The electronic device defined in  claim 1  wherein the housing structure includes a first wall portion on the first side of the cavity and a second wall portion on the second side of the cavity, wherein the first wall portion has a first infrared-transparent window through which the light emitter emits infrared light, and wherein the second wall portion has a second infrared-transparent window through which the light detector detects infrared light. 
     
     
       5. The electronic device defined in  claim 1  wherein the transreflective optical proximity sensor system comprises an additional light detector and wherein the light detector and the additional light detector detect light emitted by the light emitter that has reflected from the ear while the ear is in the cavity. 
     
     
       6. The electronic device defined in  claim 5  wherein the light emitter and the light detector detect objects in a first object detection region and wherein the light emitter and the additional light detector detect objects in a second object detection region that is different than the first object detection region. 
     
     
       7. The electronic device defined in  claim 6  wherein the first and second object detection regions are adjacent and form an enlarged object detection region. 
     
     
       8. The electronic device defined in  claim 1  wherein the transreflective optical proximity sensor system comprises:
 an additional light emitter and a corresponding additional second light detector that form an additional transreflective optical proximity sensor. 
 
     
     
       9. The electronic device defined in  claim 1  further comprising control circuitry that gathers ear presence information from the transreflective optical proximity sensor system and that stops audio playback with the speaker in response to detecting the ear in the cavity. 
     
     
       10. The electronic device defined in  claim 9  wherein the light emitter and the light detector are not located on a common side of the cavity. 
     
     
       11. The electronic device defined in  claim 9  wherein the control circuitry uses information from the transreflective optical proximity sensor system to adjust a left/right audio channel assignment while playing audio through the speaker. 
     
     
       12. Headphones, comprising:
 first and second ear cups formed from support structures defining respective first and second cavities; 
 a first speaker in the first ear cup that provides sound to the first cavity; 
 a second speaker in the second ear cup that provides sound to the second cavity; and 
 a transreflective optical proximity sensor having first and second components on opposing sides of the first cavity, wherein the first component comprises a light emitter on a first side of the first cavity, wherein the second component comprises a light detector on an opposing second side of the first cavity, and wherein the second component is configured to detect the presence of a reflected beam of light emitted by the first component. 
 
     
     
       13. The headphones defined in  claim 12  wherein the first component comprises an infrared light emitter and wherein the second component comprises an infrared light detector. 
     
     
       14. The headphones defined in  claim 13  wherein the infrared light emitter emits light into a light-emitting region, wherein the infrared light detector detects light in a light-detecting region, wherein the light-emitting region and the light-detecting region overlap in an object detection region, and wherein the first cavity receives an ear of a user in the object detection region. 
     
     
       15. The headphones defined in  claim 14  wherein the infrared light emitter and infrared light detector are configured so that the infrared light detector does not receive light from the infrared light emitter in absence of an external object in the object detection region that reflects the emitted light. 
     
     
       16. The headphones defined in  claim 13  further comprising first and second ring-shaped cushions coupled respectively to the support structures of the first and second ear cups, wherein the support structures form a housing wall with first and second infrared-transparent windows in the first cavity, wherein the infrared light emitter emits light through the first infrared-transparent window, and wherein the infrared light detector detects light through the second infrared-transparent window. 
     
     
       17. A headphone, comprising:
 a wall that forms an ear cup cavity; 
 a speaker in the cavity; 
 first and second windows in the wall on opposing sides of the cavity; and 
 a transreflective optical proximity sensor having a light emitter that emits light through the first window and a light detector that receives light through the second window without receiving emitted light directly from the light emitter, wherein the light detector is configured to receive reflected light from the light emitter. 
 
     
     
       18. The headphone defined in  claim 17  wherein the first and second windows include infrared-transparent polymer and wherein the light detector comprises an infrared light detector. 
     
     
       19. The headphone defined in  claim 17  wherein the headphone is configured to receive an ear of a user within the ear cup cavity and wherein the light emitted by the light emitter is reflected by the ear of the user. 
     
     
       20. The headphone defined in  claim 19  wherein the light detector is not configured to receive light from the light emitter when the ear of the user is not present.

Description:
FIELD 
     This relates generally to electronic devices, and, more particularly, to electronic devices with sensors. 
     BACKGROUND 
     Electronic devices often include sensors. For example, an optical proximity sensor may be used in a device such as a cellular telephone to monitor for the presence of a user&#39;s head adjacent to the cellular telephone. The optical proximity sensor may have an infrared light-emitting diode that emits infrared light and an infrared light detector that measures a portion of the emitted light that has been reflected back towards the infrared light detector from nearby objects. 
     It can be challenging to form a satisfactory optical proximity sensor for an electronic device. If care is not taken, light that is emitted by an optical proximity sensor may be reflected from static portions of the electronic device in which the optical proximity sensor system is being used rather than external objects. These static reflected signals represent a source of noise and can make it difficult to gather accurate optical proximity sensor measurements. 
     SUMMARY 
     An electronic device may include an optical proximity sensor system. The optical proximity sensor system may be a transreflective optical proximity sensor system having a light emitter that emits light into a light-emitting region and a light detector that detects light in a light-detecting region. The light emitter and detector may be placed on opposing sides of a housing or may otherwise be configured to form a transreflective sensor. Configurations in which multiple light emitters and/or light detectors are included in a transreflective optical proximity sensor system may be used, if desired. 
     Control circuitry in an electronic device can use the transreflective optical proximity sensor system to detect objects in an object detection region formed where a light-emitting region associated with a light emitter and a light-detecting region associated with a light detector overlap. During operation, the control circuitry can stop audio playback or take other suitable action in response to output from the transreflective optical proximity sensor. 
     The electronic device may be a pair of headphones with ear cups. Housing structures such as housing walls may define ear cup cavities in the ear cups that are configured to receive the ears of a user when the headphones are being worn. Speakers may be provided in the ear cups to provide sound to the ear cup cavities and the user&#39;s ears. 
     The transreflective optical proximity sensor can detect the presence of a user&#39;s ear in an ear cup cavity. In some configurations, a light emitter is formed on one side of an ear cup cavity and a light detector that does not directly receive light from the light emitter is formed on an opposing side of the ear cup cavity. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram of an illustrative electronic device in accordance with an embodiment. 
         FIG. 2  is a perspective view of an illustrative electronic device such as a pair of headphones in accordance with an embodiment. 
         FIGS. 3, 4, 5, and 6  are cross-sectional side views of illustrative electronic devices with sensor systems in accordance with embodiments. 
         FIG. 7  is a cross-sectional side view of an illustrative electronic device housing wall with a window configured to accommodate a sensor component in accordance with an embodiment. 
         FIG. 8  is a cross-sectional side view of an illustrative electronic device with a transreflective sensor system in accordance with an embodiment. 
         FIG. 9  is a top view of a user with a pair of illustrative headphones in accordance with an embodiment. 
         FIG. 10  is a side view of a headphone ear cup with transreflective optical proximity sensor components in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic devices may be provided with proximity sensor systems. The proximity sensor systems may use light-emitting and light-detecting devices to monitor for the presence of external objects. A proximity sensor system may include one or more light-emitting devices and one or more light detectors. In some configurations, the light-emitting and light-detecting devices are arranged to form a transreflective proximity sensor system in which light from a light emitter is not directly received by a corresponding light detector and in which noise contributions due to light reflections from static objects such as portions of the electronic device are reduced. 
     During operation of an electronic device with an optical proximity sensor such as a transreflective proximity sensor, emitted light from a light-emitting device may reflect (scatter) from an external object in the vicinity of the electronic device. The reflected light may be detected by a light-detecting device. When no external object is present, the amount of detected light is low. Control circuitry in the electronic device may take suitable action based on the output of the proximity sensor. 
     As one example, consider an optical proximity sensor system such as a transreflective optical proximity sensor system in an electronic device such as a pair of headphones. In this type of environment, control circuitry in the headphones can adjust audio based on whether the headphones are being worn on a user&#39;s head and/or based on whether a device is being worn in a reversed or unreversed orientation. When it is determined that the headphones are not being worn, audio playback can be stopped and/or other actions can be taken (e.g., to reduce power consumption by circuitry in the headphones). 
     As another example, a portable device such as a cellular telephone or computer can use a transreflective proximity sensor to detect hand gestures and can take action such as adjusting displayed content based on the detected hand gestures. In other types of electronic devices, other actions can be taken when external objects are detected. 
     A schematic diagram of an illustrative electronic device having an optical proximity sensor system such as a transreflective optical proximity sensor system is shown in  FIG. 1 . Device  10  may be a pair of headphones (e.g., stand-alone headphones and/or headphones associated with and/or incorporated into a head-mounted display device), earphones that are secured to the ears of a user with over-the-ear hooks, earbuds that are worn in a user&#39;s ear canals, a cellular telephone, a tablet computer, a laptop computer, a wristwatch device or other wearable device, a television, a stand-alone computer display or other monitor, a computer display with an embedded computer (e.g., a desktop computer), a system embedded in a vehicle, kiosk, or other embedded electronic device, a media player, or other electronic equipment. 
     Device  10  may include control circuitry  20 . Control circuitry  20  may include storage and processing circuitry for supporting the operation of device  10 . The storage and processing circuitry may include storage such as nonvolatile memory (e.g., flash memory or other 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  20  may be used to gather input from sensors and other input devices and may be used to control output devices. The processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processors and other wireless communications circuits, power management units, audio chips, application specific integrated circuits, etc. 
     To support communications between device  10  and external equipment, control circuitry  20  may communicate using communications circuitry  22 . Circuitry  22  may include antennas, radio-frequency transceiver circuitry, and other wireless communications circuitry and/or wired communications circuitry. Circuitry  22 , which may sometimes be referred to as control circuitry and/or control and communications circuitry, may support bidirectional wireless communications between device  10  and external equipment over a wireless link (e.g., circuitry  22  may include radio-frequency transceiver circuitry such as wireless local area network transceiver circuitry configured to support communications over a wireless local area network link, near-field communications transceiver circuitry configured to support communications over a near-field communications link, cellular telephone transceiver circuitry configured to support communications over a cellular telephone link, or transceiver circuitry configured to support communications over any other suitable wired or wireless communications link). Wireless communications may, for example, be supported over a Bluetooth® link, a WiFi® link, a 60 GHz link or other millimeter wave link, a cellular telephone link, or other wireless communications link. Device  10  may, if desired, include power circuits for transmitting and/or receiving wired and/or wireless power and may include batteries or other energy storage devices. For example, device  10  may include a coil and rectifier to receive wireless power that is provided to circuitry in device  10 . 
     Device  10  may include input-output devices such as devices  24 . Input-output devices  24  may be used in gathering user input, in gathering information on the environment surrounding the user, and/or in providing a user with output. During operation, control circuitry  20  may use sensors and other input devices in devices  24  to gather input and can control output devices in devices  24  to provide desired output. 
     Devices  24  may include speakers  14 . Speakers  14  may be used to provide audio to a user. In some configurations, device  10  may include ear cups or other headphone structures in which the speakers are housed. In other configurations, speakers  14  may be mounted in a cellular telephone or computer housing. If desired, devices  24  may include other audio devices such as one or more microphones. Microphones may be used, for example, to gather noise cancellation signals during use of speakers  14  and/or may be used in gathering voice input from a user. 
     Sensors  16  in input-output devices  24  may include force sensors (e.g., strain gauges, capacitive force sensors, resistive force sensors, etc.), audio sensors such as microphones, touch and/or proximity sensors such as capacitive sensors (e.g., a two-dimensional capacitive touch sensor associated with a display and/or a touch sensor that forms a button, trackpad, or other input device not associated with a display), and other sensors. If desired, sensors  16  may include optical sensors such as optical sensors that emit and detect light (e.g., optical proximity sensors such as transreflective optical proximity structures), ultrasonic sensors, and/or other touch and/or proximity sensors, monochromatic and color ambient light sensors, image sensors, fingerprint sensors, temperature sensors, proximity sensors and other sensors for measuring three-dimensional non-contact gestures (“air gestures”), pressure sensors, sensors for detecting position, orientation, and/or motion (e.g., accelerometers, magnetic sensors such as compass sensors, gyroscopes, and/or inertial measurement units that contain some or all of these sensors), health sensors, radio-frequency sensors, depth sensors (e.g., structured light sensors and/or depth sensors based on stereo imaging devices), optical sensors such as self-mixing sensors and light detection and ranging (lidar) sensors that gather time-of-flight measurements, humidity sensors, moisture sensors, gaze tracking sensors, and/or other sensors. In some arrangements, device  10  may use sensors  16  and/or other input-output devices to gather user input (e.g., buttons may be used to gather button press input, touch sensors overlapping displays can be used for gathering user touch screen input, touch pads may be used in gathering touch input, microphones may be used for gathering audio input, accelerometers may be used in monitoring when a finger contacts an input surface and may therefore be used to gather finger press input, etc.). 
     If desired, electronic device  10  may include additional components (see, e.g., other devices  18  in input-output devices  24 ). The additional components may include displays (e.g., an organic light-emitting diode display, a liquid crystal display, an electrophoretic display, an electrowetting display, a plasma display, a microelectromechanical systems display, a display having a pixel array formed from crystalline semiconductor light-emitting diode dies that are sometimes referred to as microLEDs, and/or other displays), haptic output devices, light producing output devices such as light-emitting diodes for status indicators, light sources such as light-emitting diodes (e.g., crystalline semiconductor light-emitting diodes) that illuminate portions of a housing and/or display structure, other optical output devices, and/or other circuitry for gathering input and/or providing output. Device  10  may also include a battery or other energy storage device, connector ports for supporting wired communication with ancillary equipment and for receiving wired power, wireless power receiving circuitry, and other circuitry. 
     A perspective view of an illustrative electronic device is shown in  FIG. 2 . In the illustrative configuration of  FIG. 2 , device  10  is a pair of headphones. Device  10  may have support structures  40 . These structures may include a supporting member such as member  30  that couples first and second (left and right) respective ear cups  32  together, support structures that form portions of ear cups  32 , and other support structures for device  10 . 
     Each ear cup  32  may have a cavity such as cavity  38  that is configured to receive a user&#39;s ear. In an illustrative configuration, cavity  38  may be surrounded by rigid cavity walls and by ring-shaped cushions  36  that are coupled to the rigid walls. Support structures  40  may include housing wall structures  34  and/or other housing structures in ear cups  32 , member  30 , ring-shaped cushions  36 , and/or other structures that support the circuitry and electrical components of device  10 . Support structures such as these, which may sometimes be referred to as housing structures or support structures for device  10 , may be configured so that device  10  of  FIG. 2  may be worn on a user&#39;s head (e.g., support structures  40  may be head-mounted support structures). Electrical components (e.g., sensors, batteries, speakers, and/or other circuitry) can be supported within interior portions of the support structures and/or on exterior portions of the support structures. For example, speakers, control circuitry, a battery, and other electrical components may be mounted in interior portions of the housing formed by support structures  40  (e.g., ear cup structures  34 , member  30 , ring-shaped cushions  36 , etc.). 
     Portions of support structures  40  may be rigid (e.g., metal structures, structures formed from glass, rigid polymer, etc.) and portions of support structures  40  may be flexible and/or soft (e.g., fabric, foam, flexible polymer structures, etc.). As an example, ear cup wall structures  34  may be formed at least partly from rigid polymer walls to provide device  10  and a transreflective optical proximity sensor system in device  10  with structural integrity and cushions  36  may be formed from soft materials such as foam covered with soft flexible polymer and/or soft fabric to enhance the comfort of ear cups  32  when worn against a user&#39;s head. 
     Device  10  may include optical proximity sensors such as transreflective optical proximity sensors. As an example, one or both of ear cups  32  may include proximity sensors to detect the presence of a user&#39;s ear in cavity  38 . In this type of arrangement, optical proximity sensors may serve as ear presence sensors. 
     In some configurations, the optical proximity sensors can determine whether a left or right ear of a user is present and can therefore be used in determining whether device  10  is being worn in an unreversed configuration (first ear cup on left ear and second ear cup on right ear) or a reversed configuration (first ear cup on right ear and second ear cup on left ear). Optical proximity sensors may therefore also serve as left/right ear sensors. Based on knowledge of whether device  10  is being worn in the unreversed or reversed orientation, left/right audio channel assignments can be adjusted accordingly (e.g., so that audio content such as an audio track associated with a video or other audio content is oriented properly for the user). 
     In general, proximity sensors can be used in any suitable portion of electronic device  10  (e.g., in a cavity formed in housing structures, on an external surface of a planar device housing, etc.). Configurations in which device  10  includes a cavity such as cavity  38  with proximity sensors may sometimes be described herein as an example. 
     A cross-sectional side view of a portion of device  10  that includes an illustrative transreflective optical proximity sensor is shown in  FIG. 3 . In the example of  FIG. 10 , device  10  has support structures  40  forming a region into which an external object may be received. Support structures  40  may, for example, be configured to form a cavity such as cavity  38  that is configured to receive a user&#39;s ear (e.g., support structures  40  may include ear cup housing wall structures  34 , ear rings  36 , and/or other housing structures). 
     Optical transreflective sensors may use one or more light emitters and one or more light detectors. The light-emitting devices of an optical transreflective sensor may include light emitters such as light-emitting diodes and/or lasers (e.g., vertical cavity surface emitting laser diodes or other laser diodes). These light emitters, which may sometimes be referred to as light sources or light transmitters, may emit light of any suitable wavelength (e.g., ultraviolet, visible, or infrared). The light-detecting devices of an optical transreflective sensor, which may sometimes be referred to as photodetectors or light receivers, may include light detectors such as silicon photodiodes, silicon phototransistors, or other semiconductor photodetectors. The light-detecting devices may be configured to detect light of the same wavelength that is being emitted by the light-emitting devices. 
     With one illustrative configuration, which may sometimes be described herein as an example, optical proximity sensor systems for devices  10  may include one or more light transmitters based on infrared light-emitting diodes (or lasers) and one or more light receivers based on infrared semiconductor photodetectors. Other light emitters and light detectors may be incorporated into optical proximity sensor systems for devices  10  if desired. 
     In the illustrative configuration of  FIG. 3 , transreflective optical proximity sensor  40  has a light emitter (e.g., an infrared light-emitting diode) such as emitter TX and a light detector such as detector RX. Emitter TX may be configured to emit light over illustrative light-emitting angular range TA. Emitter TX may include lenses, gratings, apertures, and/or other structures that configure the region into which light is emitted. Detector RX may be configured to detect incoming light rays within illustrative light-detecting angular range RA. Detector RX may include lenses, gratings, apertures, and/or other structures that configure the region from which light is detected. A sensor overlap region such as region  62  may be formed where the light-emitting region associated with light emitter TX and the light-detecting region associated with light detector RX overlap. In transreflective sensing configurations such as the configuration of  FIG. 3 , light emitter TX and light detector RX rae not located immediately adjacent to each other and do not emit and sense in tightly overlapped regions. Rather, light emitter TX and light detector RX are located in different locations on support structures  40  such as on opposing first and second housing walls formed from structures  40  that are located respectively on first and second opposing sides of cavity  38  (e.g., on the left and right of cavity  38  as shown in  FIG. 3 ). 
     With the transreflective sensing arrangement of  FIG. 3 , external objects such as object  50  (e.g., a user&#39;s ear) that are located in overlap region  62  can be sensed (e.g., control circuitry  20  can determine whether or not an ear or other external object is present in region  62 ). When object  50  is present in region  62 , emitted light rays such as light ray  58  from light emitter TX are reflected from object  50  as reflected rays that are detected by light detector RX (see, e.g., reflected ray  60 , which falls within the light detecting region associated with light detector RX). In the absence of object  50 , emitted light rays such as light ray  58  are not reflected into the light-detecting region of light detector RX and are therefore not detected. 
     In transreflective configurations of the type shown in  FIG. 3 , light detector RX does not directly receive any light from light emitter TX, because the light-emitting region associated with light emitter TX does not overlap light detector RX (as would be the case in a beam-breaking optical detector. This allows region  62  to be located near the exposed outer portion of cavity  38  while light emitter TX and light detector RX are mounted on rigid wall structures deeper in cavity  38  (e.g., the light-emitting region and light-detecting region are angled away from the back of cavity  38 ). Because external objects can be detected in region  62 , region  62  may sometimes be referred to as a transreflective sensor object detection region or object detection region. 
     In the arrangement of  FIG. 3 , region  62  is formed within cavity  38 . Configurations in which object detection region  62  is formed in other locations relative to support structures  40  may be used, if desired. 
     The transreflective sensor arrangement of  FIG. 3  may exhibit a high signal-to-noise ratio, because fixed and/or moving external objects that are outside of the detection region of interest will not reflect light from light emitter TX to light detector zone of interest. For example, external object  56  will not be detected even though this object is in the light-emitting region associated with light emitter TX, because light reflected from object  56  is not within the light-detecting region associated with light detector RX and will therefore not be detected. As another example, external objects such as object  52  may lie within the light-detecting region for light detector RX, but are not within the light-emitting region associated with light emitter TX and will not be detected because they are not illuminated by emitted light from light detector TX. Other objects such as object  54  will not be illuminated by light from light emitter TX and do not lie in the light-detecting region for light detector RX and will also not be detected. 
     In general, an optical proximity sensor system in device  10  may include beam blocking optical proximity sensor components, reflective optical proximity sensor components, and/or transreflective optical proximity sensor components. In a beam blocking sensor arrangement, a light emitter creates a beam of light that is directly detected by an associated light detector except in the presence of an external object that interrupts the beam. This type of arrangement may be difficult to use in detecting ear presence in the outer portions of cavity  38  of  FIG. 3 , because the outer portions of cavity  38  are formed by relatively soft cushions (e.g., cushions  36 ) that may not be suitable for securing optical components. In a reflective sensor arrangement, a light emitter creates an outgoing beam of light that is reflected back towards a light detector that is adjacent to the light emitter. The light-emitting angular range and light-detection angular range in a reflective sensor arrangement are generally coincident with each other, which may make reflective sensor arrangements susceptible to noise from static objects such as device housing structures and other extraneous structures that happen to fall within the range of the sensor. 
     Transreflective sensor arrangements such as the illustrative arrangement of sensor  40  of  FIG. 3  can avoid such static object reflections by appropriate placement of the overlap between the light-emitting and light-detecting regions. Transreflective optical proximity sensor arrangements are therefore helpful in arrangements in which a high signal-to-noise ratio performance is desirable such as when detecting a user&#39;s ear in the presence of a black hair, which has a low reflectivity. If desired, a transreflective optical proximity sensor system for device  10  may include sensor components that are configured to implement other proximity sensor techniques such as beam blocking and reflective sensing in addition to transreflective sensing. 
       FIG. 4  is a diagram of device  10  in an illustrative configuration in which the optical proximity sensor system for device  10  includes both a transreflective portion and a reflective portion. A single light emitter TX that emits into light-emitting range TA and a pair of first and second light detectors (light detector RX 1 , which detects light in light-detection range RA 1 , and light detector RX 2 , which detects light in light-detection range RA 2 ) are mounted to support structure  40 . The light-emitting region associated with light emitter TX is configured to overlap with the light-detecting region of light detector RX 2  in object detection region  62 - 2  while avoiding direct illumination of light detector RX 2  with light from light emitter TX to form a transreflective sensor. The light-emitting region associated with light emitter TX is configured to overlap with the light-detecting region of light detector RX 1  in object detection region  62 - 1  in a reflective sensor arrangement. 
     As described in connection with  FIG. 3 , light emitter TX and light detector RX 2 , which are located on opposing sides of cavity  38  and which are arranged so that light emitted by light emitter TX is not directly detected by light detector RX 2 , are configured to form a transreflective optical proximity sensor. Light emitter TX and light detector RX 1  of  FIG. 4  are located adjacent to each other on support structure  40  on the same side of cavity  38  and therefore form a reflective optical proximity sensor. If desired, light detector RX 1  may be located in other portions of device  10  (e.g., detector RX 1  may form a transreflective optical sensor with emitter TX by mounting detector RX 1  in illustrative location RX 1 ′). 
     As the example of  FIG. 4  demonstrates, multiple sensor components can be configured to detect objects in multiple associated object detection regions. These regions may, if desired, be located adjacent to each other (e.g., so that these regions overlap or are separated by a distance of less than 1 mm, less than 3 mm, or other small range). When used in conjunction with other, the multiple associated object detection regions form a single seamless or nearly seamless object detection region of enlarged dimensions. In the configuration of  FIG. 4 , for example, region  62 - 2  and region  62 - 1  are adjacent to each other and form a contiguous enlarged object detection region for detecting external objects within cavity  38 . 
     During operation, control circuitry  20  can use information on whether any objects have been detected in regions  62 - 1  and  62 - 2  in determining the state of device  10 . If desired, false object detections and other potential sources of error can be reduced by processing sensor output associated with both of regions  62 - 1  and  62 - 2 . As an example, if an object is detected within innermost region  62 - 1  without previous detection of the object as it passed through region  62 - 2 , the object detection event can be assumed to be erroneous and can be discarded. In general, information on the speed with which items pass through multiple object detection regions, information on the order in which items pass through multiple object detection regions, and/or information on whether an object is sufficiently large to be simultaneously detected in multiple object detection regions or is only present in a subset of the object detection regions may be used by control circuitry  20  in determining the nature of the external object and the associated operating status of device  10  (e.g., whether an ear or other object is present or absent in cavity  38 , whether device  10  is being worn on a user&#39;s head over the user&#39;s ears, etc.). 
     The illustrative sensor configuration of  FIG. 4  includes a single light emitter TX and dual light receivers RX 1  and RX 2 . If desired, multiple light emitters may be included. Consider, as an example, the arrangement of  FIG. 5 . In this type of configuration for device  10 , a first portion of a transreflective optical proximity sensor system is formed from light emitter TX 1  and light detector RX 1 . A second portion of transreflective optical proximity sensor system is formed from light emitter TX 2  and light detector RX 2 . Light emitter TX 1  and light detector RX 1  detect external objects in object detection region  62 - 1 , whereas light emitter TX 2  and light detector RX 2  detect external objects in object detection region  62 - 2 . Regions  62 - 1  and  62 - 2  may, if desired, be adjacent to each other to form an enlarged (multi-zone) object detection region for device  10 . 
       FIG. 6  is a cross-sectional side view of an illustrative ear cup for device  10 . As shown in  FIG. 6 , support structures  40  may include housing wall structures  34  and ring-shaped cushion  36 . Housing wall structures  34  may be formed from rigid polymer and/or other materials and may include one or more housing walls. For example, housing wall structures  34  may include inner housing wall  34 - 2  and outer housing wall  34 - 1 . Speaker  14  may be mounted in interior region  82  between housing wall  34 - 1  and speaker grill  40 G. Speaker grill  40 G may be formed from a material such as metal, polymer, fabric, and/or other materials and may include sound openings such as openings GP that allow sound from speaker  14  to pass to a user&#39;s ear in cavity  38 . 
     Device  10  of  FIG. 6  may include electrical components  80  such as control circuitry  20 , communications circuitry  22 , input-output devices  24 , and/or other components (batteries, wireless power circuitry, etc.). Components  80  may include integrated circuits, packaged and unpacked electrical devices, printed circuits, wires, and other circuitry for routing signals within device  10  and/or other circuitry. Components  80  may be mounted in interior regions of device  10  such as regions  82  (e.g., an area between inner and outer housing walls) and/or may otherwise be mounted in the interior of device  10  and/or on the exterior of device  10 . Components  80  may include optical proximity sensor components such as light emitters and detectors for forming transreflective optical proximity sensors of the types described in connection with  FIGS. 3, 4 , and  5  and/or other optical proximity sensor systems. Mounting components such as optical components to rigid structures such as walls  34  may help create a stable platform for the optical components. Optical components may, if desired, include components for forming a transreflective optical proximity sensor that detects the presence of a user&#39;s ear in the outer portion of cavity  38  that is bounded by ring-shaped cushion  36 . 
     In arrangements in which sensor components such as light detectors and emitters are mounted in interior region  82 , it may be desirable to form wall structures such as inner wall  34 - 2  from material that is transparent to the wavelength of light used by the light detectors and emitters (e.g., infrared light) and/or to form infrared-transparent window structures in inner wall  34 - 2 .  FIG. 7  is a cross-sectional side view of an illustrative infrared-transparent sensor window. As shown in  FIG. 7 , ear cup wall structures  34  may include inner wall  34 - 1 . Inner wall  34 - 1  may be formed from a rigid polymer that serves as part of a rigid support structure for device  10 . Openings may be formed in wall  34 - 1  to form windows such as illustrative sensor window  84 . The openings may be filled with a material such as window material  34 - 1 ′. Optical sensor components such as sensor component  86  (e.g., a light emitter TX and/or a light detector RX) may be mounted in alignment with window  84  (e.g., so that component  86  is overlapped by window material  34 - 1 ′). 
     Window material  34 - 1 ′ may be transparent to the wavelength of light used by sensor component  86 . For example, if sensor component  84  is an infrared light-emitting diode, infrared laser, or an infrared photodetector, window material  34 - 1 ′ may be formed from an infrared transparent material such as infrared-transparent polycarbonate or other infrared transparent polymer. The material of wall  34 - 1  outside of window  84  may be formed from polymer or other material that is infrared transparent or that is not infrared transparent. The material of wall  34 - 1  outside of window  84  and/or window material  34 - 1 ′ may be transparent to visible light and/or may be opaque at visible light wavelengths. In some configurations, for example, the material of wall  34 - 1  may be white or black polymer (e.g., visible-light-blocking-and-infrared-light-blocking material) and window material  34 - 1 ′ may be visible-light-blocking-and-infrared-transparent material such as visible-light-blocking-and-infrared-transparent polycarbonate or other visible-light-blocking-and-infrared-transparent polymer. Arrangements in which material  34 - 1 ′ is transparent at both visible and infrared wavelengths may also be used. 
     If desired, window  84  may include one or more optional coating layers. As an example, optional coating layer  34 - 1 C may be interposed between component  86  and window material  34 - 1 ′. Coating layer  34 - 1 C may be, for example, a visible-light-blocking-and-infrared-transparent polymer layer or a thin-film interference filter formed from multiple dielectric layers (e.g., alternating higher and lower refractive index layers) that is configured to block visible light and pass infrared light. Dyes, pigments, and other materials may be incorporated into a polymer or other material that forms coating layer  34 - 1 C (and/or material  34 - 1 ′ and wall  34 - 1 ) to provide these structures with desired optical transparency at the operating wavelength of optical component  86  while exhibiting other optical properties (e.g., a desired opacity and color) at other wavelengths. 
       FIG. 8  is a cross-sectional side view of electronic device  10  in an illustrative configuration in which device  10  is a cellar telephone, wristwatch device, tablet computer, laptop computer, or other electronic device with a display. As shown in  FIG. 8 , support structures  40  may be configured to form a housing for device  10  in which sensor components such as light emitter TX and light detector RX are mounted. Display  90  may be formed on a front face of device  10  or other suitable portion of support structures  40 . Light emitter TX may be located at a first peripheral edge of a rectangular housing formed from structures  40  and light detector RX may be located at the opposing peripheral edge of the rectangular housing (e.g., the left and right sides of structures  40  in the orientation of  FIG. 8 , which may correspond to the upper and lower ends of a cellular telephone). 
     Light emitter TX and light detector RX may, if desired, be supported by support structures  40  in a configuration in which emitter TX and detector RX form a transreflective optical proximity sensor system where the light-emitting region of light emitter TX and the light-detecting region of light detector RX overlap in a desired object detection region  62  without mounting emitter TX and detector RX adjacent to each other and without mounting emitter TX and detector RX so that light from emitter TX is directly received by detector RX. Region  62  may, for example, be located above display  90  (e.g., 1-20 cm above display  90 , at least 2 cm above display  90 , less than 15 cm above display  90 , at other distances in front of display  90 , etc.). Control circuitry  20  may control content that is displayed on display  90  while using the transreflective optical proximity sensor system formed from light emitter TX and light detector TX to monitor for the presence of external objects in region  62 . Suitable action can then be taken in response to information from the transreflective optical proximity sensor system. For example, in response to detecting a hand gesture in region  62  using one or more transreflective optical proximity sensors, control circuitry  20  can move items within the displayed content on display  90 . 
     If desired, sensor components can be arranged to detect the shape and/or other attributes of an external object in cavity  38 . Consider, as an example, the arrangement of  FIGS. 9 and 10 .  FIG. 9  is a top view of a user&#39;s head (head  120 ) onto which a pair of headphones (device  10 ) has been placed. When the headphones are being worn by user  120 , the user&#39;s ears  122  are received within cavities  38  of ear cups  32 .  FIG. 10  is a side view of ear cup  32  of  FIG. 9  showing illustrative locations for sensor components in an optical proximity sensor system such as a transreflective optical proximity sensor system. In the example of  FIG. 10 , these transreflective sensor components include light emitter TX 1  and a corresponding light detector RX 1 , light emitter TX 2  and a corresponding light detector RX 2 , and optional light emitter TX 3  and corresponding light detector RX 3 . Due to the anatomy of the user&#39;s ears, ears  122  are not symmetrical (e.g., from front to back). As a result, more portions of the user&#39;s ear (see, e.g., illustrative portions  122 F of  FIG. 10 ) may be located in the object detection region associated with emitter TX 2  and detector RX 2  than are located in the object detection region associated with emitter TX 1  and detector RX 1  (or vice versa). As a result, when the signal from detector RX 2  is greater than the signal from RX 1 , control circuitry  20  can conclude that ear cup  32  is located on the user&#39;s right ear and when the signal from detector RX 1  is greater than the signal from RX 2 , control circuitry can conclude that ear cup  32  is located on the user&#39;s left ear (as an example). The signal from detector RX 3  can be used to confirm that ear  122  is present and/or can help distinguish between the user&#39;s left and right ears. 
     After using an arrangement of the type shown in  FIG. 10  or other transreflective optical proximity sensor system that is sensitive to left/right ear determinations, control circuitry  20  can take suitable action. For example, control circuitry  20  can reverse the left/right channel assignments in device  10  in response to determining that device  10  is being worn in a reversed configuration or may take other actions in response to the measured left/right orientation of ear cups  32  on the user&#39;s ears  122 . 
     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: 20180723
Publication Date: 20190528
Grant Date: 20190528
Priority Date: 20180723
Inventors: LIN, TSU-HUI
CAI, WENRUI
ZHANG, XIAOYANG
KUBOYAMA, YUTA
CHANDRAN, PRAVEESH
Assignee: APPLE INC
CPC Classifications: [{"code": "G01S17/04", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04R1/1008", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R1/1008", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R2201/107", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R1/1075", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R2420/07", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R1/1041", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04R1/1075", "inventive": false, "first": false, "tree": "[]"}, {"code": "G01S17/08", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04R2201/109", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R2420/07", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R1/1041", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04R1/1008", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04R2420/07", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R1/1075", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01S17/08", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04R1/1041", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04R2201/109", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04R2201/107", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 66636272