PATENT DOCUMENT

Publication Number: US-9019428-B2
Application Number: US-201213605837-A
Country: US
Kind Code: B2

Title: Electronic device camera module with alignment structures

Abstract:
An electronic device may include a camera module. Control circuitry within the electronic device may use an image sensor within the camera module to acquire digital images. The camera module may have lens structures that are supported by lens support structures such as a lens barrel and lens carrier. An actuator such as a voice coil motor may control the position of the lens support structures relative to internal support structures such as upper and lower spacer members. Springs may be used to couple the lens support structures to the internal support structures. Outer wall structures in the camera module such as a ferromagnetic shield structures may surround and enclose at least some of the internal support structures. The outer wall structures may have openings. The internal support structures may have pins or other alignment structures that protrude through the openings.

Claims:
What is claimed is: 
     
       1. A camera module configured to be mounted in an electronic device that has alignment structures, comprising:
 lens support structures containing at least one lens; 
 internal support structures; 
 outer wall structures that surround and enclose at least part of the internal support structures; 
 an actuator that moves the lens support structures relative to the internal support structures; 
 a digital image sensor that receives light through the lens, wherein the internal support structures have alignment structures configured to mate with the alignment structures of the electronic device; and 
 flexible coupling structures with which the internal support structures support the lens support structures. 
 
     
     
       2. The camera module defined in  claim 1  wherein the actuator comprises a voice coil motor including a magnet and a coil and wherein the outer wall structures comprise a ferromagnetic shield. 
     
     
       3. The camera module defined in  claim 2  wherein the alignment structures of the internal support structures comprise protrusions. 
     
     
       4. The camera module defined in  claim 3  wherein the internal support structures comprise a plastic member and wherein the protrusions comprise pins that are integral portions of the plastic member. 
     
     
       5. The camera module defined in  claim 4  wherein the ferromagnetic shield has openings through which the pins protrude. 
     
     
       6. The camera module defined in  claim 3  wherein the internal support structures comprise a plastic member and wherein the protrusions of the alignment structures of the internal support structures comprise metal pins that are insert molded within the plastic member. 
     
     
       7. The camera module defined in  claim 6  wherein the ferromagnetic shield has openings through which the pins protrude. 
     
     
       8. The camera module defined in  claim 2  wherein the alignment structures of the electronic device comprise at least one protrusion and wherein the alignment structures of the internal support structures comprise at least one recess configured to receive the protrusion. 
     
     
       9. The camera module defined in  claim 3 , wherein the flexible coupling structures comprise at least one spring. 
     
     
       10. The camera module defined in  claim 9  wherein the ferromagnetic shield comprises a lip configured to arrest motion of the lens support structures relative to the internal support structures. 
     
     
       11. An electronic device, comprising:
 structures that include alignment features; and 
 a camera module having a ferromagnetic shield and internal support structures within the ferromagnetic shield that have portions that mate with the alignment features, wherein the ferromagnetic shield has openings and wherein the portions pass through the openings to mate with the alignment features. 
 
     
     
       12. The electronic device defined in  claim 11  wherein the portions comprise alignment pins. 
     
     
       13. The electronic device defined in  claim 12  wherein the alignment features comprise an alignment ring and wherein the alignment pins protrude into the alignment ring. 
     
     
       14. The electronic device defined in  claim 13  wherein the camera module comprises lens structures and a voice coil motor configured to move the lens structures relative to the alignment pins. 
     
     
       15. The electronic device defined in  claim 14  further comprising:
 a display having a display cover layer with an opaque masking layer, wherein the opaque masking layer has a camera window opening, and wherein the structures that include the alignment features comprise an alignment structure having an opening that is aligned with the camera window opening. 
 
     
     
       16. The electronic device defined in  claim 15  wherein the alignment structure has a recess that is configured to receive one of the alignment pins to serve as part of the alignment features. 
     
     
       17. The electronic device defined in  claim 12  further comprising:
 a housing wall having a camera window opening; and 
 a transparent camera window member, wherein the structures that include the alignment features comprise a camera window trim member with which the transparent camera window member is installed in the camera window opening. 
 
     
     
       18. The electronic device defined in  claim 17  wherein the camera window trim member has a recess that is configured to receive one of the alignment pins to serve as part of the alignment features. 
     
     
       19. The electronic device defined in  claim 12  further comprising:
 a housing wall having a camera window opening; and 
 a transparent camera window member aligned with the camera window opening, wherein the housing wall has a recess that is configured to receive one of the alignment pins to serve as part of the alignment features. 
 
     
     
       20. A camera module configured to be mounted in an electronic device that has alignment structures, comprising:
 lens support structures containing at least one lens; 
 internal support structures; 
 outer wall structures that surround and enclose at least part of the internal support structures; 
 an actuator that moves the lens support structures relative to the internal support structures; and 
 a digital image sensor that receives light through the lens, wherein the internal support structures have alignment structures configured to mate with the alignment structures of the electronic device, wherein the alignment structures of the internal support structures comprise protrusions, wherein the internal support structures comprise a plastic member, and wherein the protrusions of the alignment structures of the internal support structures comprise metal pins that are insert molded within the plastic member.

Description:
BACKGROUND 
     This relates generally to electronic devices, and more particularly, electronic devices having camera modules. 
     Electronic devices such as portable computers, tablet computers, and cellular telephones are often provided with camera modules. The camera modules include digital image sensors and additional structures such as a lens and autofocus structures. 
     It may be challenging to provide camera modules that are as compact as desired and that are satisfactorily aligned with respect to device housing structures. In some situations, a camera module may be mounted with a bulky bracket that introduces a possible source of misalignment between the camera module and other device structures. To accommodate potential misalignment, camera window structures may need to be enlarged. This may allow stray light to enter a device and degrade image quality. Mounting structures such as brackets may also consume more volume than desired in an electronic device, making it difficult to reduce the size of the device. 
     It would therefore be desirable to be able to provide improved ways of installing camera modules in electronic devices. 
     SUMMARY 
     An electronic device may include a camera module. Control circuitry within the electronic device may use an image sensor within the camera module to acquire digital image data. 
     The camera module may have lens structures that are supported by lens support structures such as a lens barrel and lens carrier. An actuator such as a voice coil motor may control the position of the lens support structures relative to internal support structures such as upper and lower spacer members. During operation, the control circuitry may adjust the actuator to focus light that is passing through the lens structures onto the image sensor. Springs or other flexible coupling structures may be used to couple the lens support structures to the internal support structures. 
     Outer wall structures in the camera module such as ferromagnetic shield structures may surround and enclose at least some of the internal support structures. The outer wall structures may have a lip that serves as a stop to arrest motion of the lens support structures. The lip of the ferromagnetic shield structures may have openings. The internal support structures may have pins or other alignment structures that protrude through the openings. 
     The electronic device may include structures with alignment features that mate with the alignment structures on the internal camera module support structures. The alignment features may be formed from recesses that are configured to receive the pins that are protruding through the openings in the ferromagnetic shield structures. The alignment features in the electronic device may be formed as part of a housing wall, as part of an alignment ring that surrounds a camera window opening and that is mounted on the inner surface of a display cover glass, as part of a camera window trim structure, or as part of other structures in the electronic device. 
     After a camera module has been assembled, test equipment may be used to measure how much the image sensor is offset with respect to the alignment structures. The test equipment may determine, for example, that the image sensor is tilted. Calibration data may be generated to compensate for the measured offset of the image sensor in a camera module. Following assembly of a camera module into an electronic device, the calibration data for that camera module may be loaded into control circuitry within the electronic device so that the control circuitry can rotate acquired digital images by an amount that compensates for the measured tilt. 
     Further features of the invention, its nature and various advantages will be more apparent from the accompanying drawings and the following detailed description of the preferred embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front perspective view of an illustrative electronic device of the type that may include a camera module in accordance with an embodiment of the present invention. 
         FIG. 2  is a rear perspective view of an illustrative electronic device of the type that may include a camera module in accordance with an embodiment of the present invention. 
         FIG. 3  is a cross-sectional side view of an illustrative electronic device with a camera module that is aligned with respect to alignment features formed from recessed portions of an alignment ring mounted on a display cover layer in accordance with an embodiment of the present invention. 
         FIG. 4  is a cross-sectional side view of an illustrative electronic device with a camera module that is aligned with respect to protruding portions of an alignment ring mounted on a display cover layer in accordance with an embodiment of the present invention. 
         FIG. 5  is a cross-sectional side view of an illustrative electronic device with a camera module that is aligned to a window in a device housing recesses in the device housing that serve as camera module alignment features in accordance with an embodiment of the present invention. 
         FIG. 6  is a cross-sectional side view of an illustrative camera module and associated camera window trim structures having mating alignment features in accordance with an embodiment of the present invention. 
         FIG. 7  is a perspective view of an illustrative structure with alignment features configured to mate with alignment features on a camera module in accordance with an embodiment the present invention. 
         FIG. 8  is a cross-sectional side view of a portion of a camera module having a shield with an opening through which an alignment pin passes in accordance with an embodiment of the present invention. 
         FIG. 9  is a cross-sectional side view of an illustrative camera module alignment pin formed from an insert molded metal part in accordance with an embodiment of the present invention. 
         FIG. 10  is a cross-sectional side view of an illustrative camera module alignment pin with straight edges in accordance with an embodiment of the present invention. 
         FIG. 11  is a cross-sectional side view of an illustrative camera module alignment pin with a beveled edge in accordance with an embodiment of the present invention. 
         FIG. 12  is a perspective view of an illustrative camera module alignment structure in accordance with an embodiment of the present invention. 
         FIG. 13  is a cross-sectional side view of an illustrative camera module alignment recess with a beveled edge portion in accordance with an embodiment of the present invention. 
         FIG. 14  is a perspective view of interior portions of a camera module in accordance with an embodiment of the present invention. 
         FIG. 15  is a perspective view of an illustrative camera module with alignment features in accordance with an embodiment of the present invention. 
         FIG. 16  is a cross-sectional side view of a camera module of the type shown in  FIG. 15  in accordance with and embodiment of the present invention. 
         FIG. 17  is a system diagram showing illustrative test equipment of the type that may be used in characterizing camera modules in accordance with an embodiment of the present invention. 
         FIG. 18  is a schematic diagram of an electronic device in accordance with an embodiment of the present invention. 
         FIG. 19  is a flow chart of illustrative steps involved in fabricating, characterizing, installing, and using a camera module in an electronic device in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic devices such as electronic device  10  of  FIG. 1  may be provided with camera modules. Digital images may be captured using a camera module. There may be any suitable number of camera modules in device  10 . For example, there may be one camera module in the camera systems of device  10 , there may be two camera modules in device  10 , or there may be three or more camera modules in device  10  (as examples). 
     Device  10  of  FIG. 1  may be portable electronic equipment such as a cellular telephone, a tablet computer, a media player, a wrist-watch device, a pendant device, an earpiece device, a notebook computer, other compact portable devices, or other electronic equipment such as a computer monitor with an integrated computer, a computer monitor, a desktop computer, a set-top box, or a television. 
     Device  10  of  FIG. 1  may include a housing such as housing  12 . Housing  12 , which may sometimes be referred to as a case, may be formed of plastic, glass, ceramics, fiber composites, metal (e.g., stainless steel, aluminum, etc.), other suitable materials, or a combination of these materials. Housing  12  may be formed from a unibody structure (e.g., a structure that is machined from a single piece of material) or may include internal frame structures and exterior wall structures (as examples). Other types of housing construction may also be used if desired. 
     Device  10  may, if desired, have a display such as display  14 . Display  14  may be a touch screen that incorporates touch sensitive structures such as capacitive touch electrodes or display  14  may be touch insensitive. Display  14  may include display pixels formed from light-emitting diodes (LEDs), organic LEDs (OLEDs), plasma cells, electrophoretic display elements, electrowetting display elements, liquid crystal display (LCD) components, or other suitable display pixel structures. A cover layer such as a layer of glass or clear plastic may cover the surface of display  14 . Buttons and speaker port openings may pass through openings in the cover glass. For example, the cover layer for display  14  may have an opening for a front-facing button such as button  16  and a speaker opening such as speaker port opening  18 . 
     Portions of display  14  may form active regions (i.e., regions in which the display pixels of display  14  form images for a user). Portions of display  14  may also form inactive regions (e.g., peripheral portions of display  14  that to not have any active display pixels). Camera window structures such as camera window structure  20  may be provided in the cover layer for display  14  (e.g., to form a front-facing camera). The camera windows structures may be formed from transparent materials such as glass, plastic, or other transparent materials. Camera window  20  of  FIG. 1  may, for example, be formed in an inactive portion of display  14 . The display cover layer in the inactive portion of display  14  may be provided with an opaque masking layer such as a layer of black ink. Camera window  20  may be formed from an opening in the opaque masking layer. 
     If desired, camera windows  20  may be formed elsewhere in device housing  12 . As shown in the rear perspective view of device  10  of  FIG. 2 , for example, camera window  20  may be formed on the rear surface of housing  12  (e.g., to form a rear-facing camera). 
       FIG. 3  is a cross-sectional side view of electronic device  10  showing how device  10  may include a camera module such as camera module  22 . As shown in  FIG. 3 , device  10  may include a display cover layer such as display cover layer  23 . Display cover layer  23  may be a transparent sheet of material that covers the surface of display  14  of  FIG. 1 . Display cover layer  23  may be formed from a material such as clear glass or plastic (as examples). In inactive portions of display  14  such as the end portions of display  14  at the top and bottom of device  10  of  FIG. 1 , the underside of display cover layer  23  may be covered with an opaque masking material such as black ink  24 . Opening  26  may be formed in black ink layer  24  to serve as a camera window for camera module  22 . Camera module  22  may be aligned with opening  26  so that light  36  from an image subject may pass through opening  26  to camera module  22 . Camera module  22  may include one or more lenses such as lens structures  38  and may include a digital image sensor such as image sensor  40  onto which light  36  that has passed through lens structures  38  is focused. Using lens structures  38  and image sensor  40 , camera module  22  may generate digital image data corresponding to image light  36 . 
     When assembled into a finished device, camera module  22  may be pressed upwards in direction  42  by housing  12  and optional biasing structures such as elastomeric structure  34 . Elastomeric structure  34  may be formed from a silicone pad, foam, springs, or other biasing structures. 
     When biased towards display cover layer  23  by biasing structures  34 , alignment features  32  on camera module  22  may mate with corresponding alignment features such as alignment features  30  on structures such as alignment structures  28 . Alignment structures  32  may be pins or other protruding structures and alignment structures  30  may be mating recesses or other recessed structures (as an example). Adhesive or other suitable attachment mechanisms may be used to attach alignment structures  28  to display cover layer  23 . Alignment structures  28  may, as an example, have the shape of a ring. The ring may have a circular opening that is aligned with circular opening  26  in black ink layer  24  and may surround opening  26 . Alignment structures  28  and the structures in camera module  22  such as alignment structures  32  may be formed from plastic, ceramic, glass, metal, fiber-based composites, other materials, or a combination of these materials. 
     Using vertically protruding pins as camera module alignment structures in a configuration of the type shown in  FIG. 3  allows camera module  22  to be aligned with respect to alignment ring  28  and other structures in device  10  without using excessively bulky mounting bracket structures surrounding the sides of camera module  22 . Pins  32  or other camera module alignment structures can also be formed as integral portions of internal camera module structures, thereby enhancing alignment accuracy. 
     As shown in  FIG. 4 , alignment features  30  on alignment ring  28  may be formed from protruding portions of alignment ring  28 . As shown by illustrative metal structure  30 ′, alignment features  30  may, if desired, be formed from metal structures that are molded within alignment ring  28  (e.g., by insert molding) or may be formed from screws, pins, or other metal structures that are separate from alignment ring  28 . For example, alignment ring  28  may have holes through which screws pass. The screws may have threaded shafts that are received in threaded bores in camera module  22 . Following attachment of alignment ring  28  to camera module  22  using screws, alignment ring  28  may be attached to display cover layer  23  using adhesive (as an example). In configurations in which alignment features  30  have protruding shapes of the type shown in  FIG. 4 , corresponding alignment features  32  may have the shapes of recesses in the structures of camera module  22 . Alignment feature arrangements may also be used in which ring  28  or other alignment structures on display cover layer  23  have a combination of recessed and protruding regions and mating alignment structures on camera module  22  have a combination of protruding and recessed regions. 
     In the illustrative configuration of  FIG. 5 , device  10  has a camera window such as camera window  46  that has been formed in a wall of housing  12 . Camera window  46  of  FIG. 5  may be, for example, a camera window such as rear housing surface camera window  20  of  FIG. 2 . As shown in  FIG. 5 , camera window  46  may be formed from a clear structure such as camera window structure  44  that is mounted within an opening in housing  12 . Camera window structure  44  may be a glass or plastic disk or other transparent member. Adhesive, fasteners, or other mounting structures may be used in attaching transparent camera window member  44  to housing  12 . 
     Camera window structure  44  allows light from an image to reach camera module  22 . Camera module  22  and housing  12  may have mating alignment features. For example, housing  12  may have integral alignment features such as protrusions or recesses that mate with camera module alignment features. As shown in  FIG. 5 , for example, housing  12  (e.g., a plastic, glass, metal, or fiber-composite housing wall) may be provided with alignment features such as recesses  30  that mate with corresponding camera module alignment features  32  such as protrusions (e.g., alignment pins). 
     If desired, camera windows in device  10  can be formed using trim structures such as camera window trim  48  of  FIG. 6 . Camera window trim structure  48  may be formed from plastic, metal, glass, fiber-based composites, or other suitable materials. Camera window trim structure  48  may have a circular opening or an opening of other suitable shapes for receiving camera window member  52 . Camera window member  52  may be a piece of glass, plastic, or other transparent camera window structure. For example, camera window member  52  may be a clear disk-shaped glass or plastic structure that is received within a mating circular recess within camera trim structure  48 . Camera trim structures  48  may be used in mounting camera window member  52  within an opening in housing  12 . Camera trim structure  48  may have protruding portions such as portions  50  that are visible from the exterior of device  10  and that surround camera window member  52 . Portions  50  may, for example, for a circular trim for window  52  in configurations in which camera window member  52  has a disk shape. A ring-shaped layer of black ink or other opaque masking material  54  may be provided around the peripheral edge of camera window member  52 . 
     Portions of camera window trim structures  48  may be configured to serve as alignment features that mate with corresponding alignment features on camera module  22 . As an example, camera module  22  may have pins or other protruding camera module alignment features  32  and camera window trim structures  48  may have mating alignment structures such as recesses  30 . Configurations in which camera module  22  has recessed alignment features and camera window trim structure  48  has mating protruding alignment features may also be used. Adhesive or other attachment mechanisms may be used to attach camera window trim  50  and camera window member  52  to housing  12 . 
       FIG. 7  is a perspective view of illustrative alignment structures of the type that may be used in receiving alignment features such as protruding portions  32  on camera module  22 . Alignment structures  56  may, as an example, be used as an alignment ring such as alignment ring  28  of  FIG. 3  and alignment ring  28  of  FIG. 4 . As shown in  FIG. 7 , alignment structures  56  may have an opening such as opening  58  for receiving a circular (disk-shaped) camera window member. Openings  30 - 1  and  30 - 2  may be used in forming alignment structures  30 . Opening  30 - 1  may be a hole with a circular shape for receiving a mating circular pin  32  on camera module  22 . Opening  30 - 2  may have a slot-shaped opening (e.g., a rectangular slot shape with rounded corners). The use of a slot or other laterally elongated opening shape for opening  30 - 2  provides extra clearance to help ensure that pins  32  will be successfully received within openings  30 - 1  and  30 - 2 . 
     Protruding alignment features such as pins  32  on camera module  22  may pass through an opening in an outer structure on module  22  such as outer wall structure  60 . Outer wall structures  60  may form a camera module housing wall or other structure that surrounds and encloses at least some of the internal parts of camera module  22 . In configurations in which camera module  22  uses an electromagnetically actuated focusing system (e.g., an actuator such as a voice coil motor that is based on a coil of wire and permanent magnets or other electromagnetic actuator), outer wall structures  60  may be an electromagnetic shield structure and may be formed from a ferromagnetic metal (e.g., a sheet of steel coated with one or more layers of additional metals). The ferromagnetic metal may allow structures  60  to serve as a shield that helps direct and confine electromagnetic fields from coil and magnet structures within camera module  22 . 
     As shown in  FIG. 8 , camera module wall structures  60  may have openings such as opening  62  through which protruding portions of camera module  22  such as pin  32  may protrude. Pin  32  may be coupled to internal camera module structures such as internal structures  64 . Internal structures  64  may, in turn, form support structures for a lens barrel and other internal camera module structures. By allowing pins  32  to protrude through opening  62  in camera module wall  60 , pins  32  can engage directly with mating alignment features in device  10 , thereby enhancing alignment accuracy. 
     In the illustrative configuration of  FIG. 8 , pins  32  have been formed as portions of internal camera structures  64 . Structures  64  may be plastic support structures and pins  32  may be plastic protrusions that are formed as integral portions of structures  64 . As shown in  FIG. 9 , pins  32  may, if desired, be formed from a material that is different than the material used in forming internal structures  64 . For example, pins  32  may be formed from metal and internal structures  64  may be formed from plastic. To hold pins  32  in place within structures  64 , structures  64  may be formed by injection molding plastic around the base portion of pins  32  (i.e., pins  32  may be attached to structures  64  using insert molding techniques). 
     Pins  32  may have a cross-sectional shape with straight sidewalls  66  and a planar upper surface  68 , as shown in  FIG. 10 . Sidewalls  66  may meet upper surface  68  at right-angled corners  70 .  FIG. 11  shows how pin  32  may be provided with a chamfered corner along chamfered peripheral edge  70 ′ to facilitate insertion of pin  32  into mating recess  30  in structures associated with device housing  12  (e.g., alignment structures, trim structures, or integral housing wall structures). 
       FIG. 12  is a perspective view of an illustrative pyramid-shaped structure of the type that may be used in forming pins  32 . As shown in  FIG. 13 , mating alignment features on device housing  12  such as recess  30  may, if desired be provided with a cross-sectional shape having sloped wall portions such as chamfered edge  72 . Alignment features  30  and  32  may be provided with other shapes if desired. The illustrative configurations of  FIGS. 10 ,  11 ,  12 , and  13  are merely illustrative. 
     Illustrative internal camera module structures for camera module  22  (i.e., structures not covered by outer wall structures  60 ) are shown in  FIG. 14 . As shown in  FIG. 14 , camera module  22  may have structures such as lower support member  74  and upper support member  64 . Lower support member  74 , which may sometimes be referred to as a lower spacer, may be formed from a material such as plastic. Upper support member  64 , which may sometimes be referred to as an upper spacer, may also be formed from a material such as plastic. Opening  84  in upper support member  64  may be used to receive lens structures such as one or more lenses mounted in a threaded lens barrel. 
     The lens structures of camera module  22  may be held in place using springs or other flexible structures that allow the lens structures to move relative to support structures such as upper support member  64  and lower support member  74 . For example, lenses may be mounted within a lens barrel that is screwed into a corresponding lens carrier. The lens carrier may be mounted for movement relative to members  64  and  74  using structures such as upper spring structures  78  on member  64  and lower spring structures  82  on member  74 . 
     During operation, the lens carrier may be moved back and forth along lens axis  86  to focus camera module  22 . Springs  78  and  82  may support the lens carrier while allowing the lens carrier to move along axis  86 . Camera module  22  may position the lens carrier and the lenses within the lens carrier relative to support structures such as members  64  and  74  using an actuator that is based on electromagnetic structures such as wire coils (electromagnetics) and/or permanent magnets, piezoelectric actuator structures, stepper motors, shape memory metal structures (e.g., actuators that move the lens carrier by heating and cooling nitinol structures), or other actuator structures. Examples of electromagnetic actuators include moving coil actuators and moving magnet actuators. Actuators that use no permanent magnets (e.g., actuators based on a pair of opposing electromagnets) may also be used. 
     In the illustrative configuration of  FIG. 14 , an actuator for camera module  22  has been formed using permanent magnets  78  and coils  80 . This type of actuator arrangement, which may sometimes be referred to as a voice coil motor (VCM) arrangement, may be controlled electrically using by control signals from control circuitry within device  10  to control the amount of current flowing through coils  80 . 
       FIG. 15  is a perspective view of an illustrative camera module of the type shown in  FIG. 14  in which the internal components of  FIG. 14  have been encased within outer wall structures  60 . Outer wall structures  60  may form a camera module housing sheet metal structures covered with optional metal coatings. Outer wall structures  60  may be formed from a ferromagnetic metal so that outer wall structures  60  serve as a ferromagnetic shield. Openings  62  in outer wall structures  60  (e.g., in lip portion  101 ) may allow pins  32  to protrude from member  64  upwards in direction  42 . 
     A cross-sectional view of camera module  22  of  FIG. 15  taken along line  90  and viewed in direction  92  is shown in  FIG. 16 . As shown in  FIG. 16 , camera module  22  may have lens support structures formed from lens carrier structure  114  and lens barrel  94 . One or more lenses such as lenses  96  may be mounted within lens barrel  94 . Lens barrel  94  may have a cylindrical surface with threads  112  that mate with corresponding threads on the interior surface of a cylindrical hole in lens carrier  114 . Light that passes through camera window  26  and lenses  96  is focused onto image sensor  98 . An optional infrared cut filter  116  may be used to prevent infrared light from reaching sensor  98 . Image sensor  98  may be attached to camera module support structures such as lower support member  74  (e.g., in a recess in member  74  or on a lower surface of support member  74 ). 
     Lens carrier  114  (and lens barrel  94  in carrier  114 ) may be supported for motion along lens axis  86  using flexible spring structures such as upper spring  100  and lower spring  106 . Upper spring  100  may be attached to lens carrier  114  using adhesive or one or more heat stakes on lens carrier  114  such as heat stakes  104 . Upper spring  100  may be attached to upper support member  64  using adhesive or one or more heat stakes on upper support member  64  such as heat stakes  102 . Lower spring  106  may be attached to lens carrier  114  using adhesive or one or more heat stakes on lens carrier  114  such as heat stakes  110 . Lower spring  106  may be attached to lower support member  74  using adhesive or one or more heat stakes such as heat stakes  108 . 
     Coils  80  may be attached to lens carrier  114 . Magnets  78  may be mounted on the interior surface of outer housing walls  60  (e.g., a ferromagnetic shield). Housing walls  60  may be attached to upper and lower support members  64  and  74  using adhesive, fasteners, or other suitable attachment mechanisms. During operation, current applied to coils  80  will cause coils  80  and therefore lens carrier  114  and lenses  96  to move relative to magnets  78  and upper and lower support members  64  and  74 . Lip portion  101  of outer wall structures  60  may serve as a stop feature. Lip portion  101  may, for example, be contacted by upper surface  103  of lens carrier  114  during movement of lens carrier  114  in direction  42  and may thereby arrest upward motion of lens carrier  114  and lenses  96  in direction  42  to prevent over-travel of lenses  96 . 
     With the arrangement of  FIG. 16 , lenses  96  are mounted in lens support structures formed from lens carrier  114  and lens barrel  94 . Using springs  100  and  106 , these lens support structures are coupled to internal support structures such as upper member  64  and lower member  74 . Upper member  64  has pins  32  that directly mate with alignment features such as circular opening  30 - 1  and slot-shaped opening  30 - 2  in alignment ring  28 , thereby aligning camera module  22  without introducing alignment tolerance variations due to the presence of outer wall structure  60 . Pins  32  may also mate with other types of alignment features in device  10  if desired, as described in connection with  FIGS. 3-6 . 
       FIG. 17  is a diagram of a system of the type that may be used in testing camera modules such as camera module  22  during manufacturing. As camera module  22  is assembled during manufacturing, structures within module  22  such as image sensor  98  may be laterally and rotationally offset from their desired location. Test equipment  120  may be used in measuring module  22  to determine the magnitude of any placement offsets in the images acquired by image sensor  98  relative to alignment pins  32 . Image offsets may arise, for example, because image sensor  98  and/or associated lens structures in module  22  are misaligned. 
     During testing, module  22  may be mounted in a test fixture such as test fixture  126 . Test fixture  126  may have recesses or other alignment features that mate with alignment pins  32  on camera module  22 . Test unit  124  (e.g., a computer or other control circuitry) may issue commands to test pattern generator  122  and module  22  that direct module  22  to acquire test images while test pattern generator  122  generates known test patterns of light. As test pattern generator  122  applies test patterns to module  22 , test unit  124  may use image sensor  98  in module  22  to acquire the test images. Test unit  124  may then analyze the acquired digital image test data to determine the magnitude of any lateral (X, Y, and Z) offsets and rotational offsets (about X, Y, and Z axes) exhibited by image sensor  98  and/or the images acquired by image sensor  98  relative to pins  32 . As an example, test equipment  120  may determine that a particular camera module has an image sensor that is tilted by 1 degree relative to its desired orientation. 
       FIG. 18  is a schematic diagram of device  10  showing how device  10  may include control circuitry  130 , camera module  22 , and other components  132 . Camera module  22  may be used to acquire digital image data (e.g., still images and/or video). Components  132  may include sensors, input-output devices such as touch screens, buttons, data ports, audio jacks, wireless and wired communications circuitry, displays, status indicators, and other circuitry for operating device  10 . 
     Control circuitry  130  may include one or more processors, memory, application specific integrated circuits, and other storage and processing circuitry. Control circuitry  130  may be used to store calibration data from test equipment  120 . For example, control circuitry  130  may be used to store calibration data from test equipment  120  that indicates to control circuitry  130  how much tilt or other offset a particular camera module  22  that has been installed within device  10  is exhibiting. Control circuitry  130  may be used to run software on device  10  such as operating system software and application software. The software may allow control circuitry  130  to process images from camera module  22 . For example, if stored calibration data in memory in control circuitry  130  indicates that camera module  22  has an image sensor that is tilted by 1° relative to horizontal, image processing software that is implemented on control circuitry  130  can automatically rotate each acquired image by a compensating 1° in the opposite direction to ensure that final images for device  10  are not tilted. 
     Illustrative steps involved in calibrating electronic device  10  to compensate for offsets of image sensor  98  relative to alignment features  32  in camera module  22  and involved in using device  10  following calibration are shown in  FIG. 19 . 
     At step  140 , the components of camera module  22  such as image sensor  98  and the other structures of  FIG. 16  may be assembled to form camera module  22 . Due to manufacturing variations, image sensor  98  and other components may not be perfectly aligned with respect to alignment features such as pins  32  on camera module  22 , leading to a potential misalignment of the images produced by image sensor  98 . For example, if image sensor  98  is tilted, raw images acquired by camera module  22  will also be tilted. 
     At step  142 , test equipment such as test equipment  120  of  FIG. 17  may be used to characterize the location of image sensor  98  and other components (and/or the position of acquired images) relative to alignment features  32 . In particular, test equipment  120  may align camera module  22  relative to a fixture while applying a test pattern using test pattern generator  122 . Computing equipment such as test host  124  of  FIG. 17  may gather images from camera module  22  while the test pattern from test pattern generator  122  is being provided to image sensor  98 . By processing the images that are acquired, test host  124  can ascertain how much image sensor  98  (and/or the image data acquired by module  22 ) is offset from its desired location. Test host  124  may then generate corresponding calibration data for compensating for the offsets that were measured. As an example, if a given camera module exhibits 0.1 mm of offset along a Y axis and 1.3° of tilt about a Z axis, calibration data that represents this lateral and rotational offset information can be stored in a database in test equipment  124  for use in calibrating that camera module when installed in an electronic device. 
     After camera module  22  has been characterized to determine how much image offset is associated with camera module  22 , camera module  22  may be installed within housing  12  of electronic device  10 . Control circuitry  130  may be coupled to computing equipment such as test equipment  124  that has access to the database of calibration data acquired during the characterizing operations of step  142 . During the operations of step  144 , the computing equipment may use paths such as path  134  of  FIG. 18  to store the calibration data for the installed camera module that was acquired during the operations of step  142  in storage within control circuitry  130 . Following calibration of the electronic device in this way, the electronic device may be shipped to an end user. 
     At step  146 , a user of device  10  may acquire still or moving images with camera module  22 . Because camera module  22  has offsets of 0.1 relative to a Y axis and a tilt of 1.3° about a Z axis (in this example), the images that are acquired will be laterally offset and tilted by a corresponding amount. However, because control circuitry  130  has been provided with calibration data, control circuitry  130  can automatically process each acquired image from camera module  22  to remove the lateral and rotational offsets. Images that are stored in control circuitry  130  for use by the user may therefore appear accurately centered and not tilted. 
     The foregoing is merely illustrative of the principles of this invention and various modifications can be made by those skilled in the art without departing from the scope and spirit of the invention. Any of the foregoing embodiments may be used alone or in combination with one or more of any of the other foregoing embodiments.

Metadata:
Filing Date: 20120906
Publication Date: 20150428
Grant Date: 20150428
Priority Date: 20120906
Inventors: SHUKLA ASHUTOSH Y.
WILLIAMS KENTA K.
HEGDE SHASHIKANT G.
TAN TANG YEW
PAKULA DAVID A.
Assignee: APPLE INC
CPC Classifications: [{"code": "H04N23/57", "inventive": true, "first": false, "tree": "[]"}, {"code": "G03B17/12", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04N23/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N23/57", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N5/2257", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N17/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N5/225", "inventive": true, "first": false, "tree": "[]"}, {"code": "G03B13/18", "inventive": true, "first": true, "tree": "[]"}, {"code": "G03B17/12", "inventive": true, "first": false, "tree": "[]"}, {"code": "G03B2217/002", "inventive": false, "first": false, "tree": "[]"}, {"code": "G03B13/18", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04N17/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "G03B2217/002", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04N23/00", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 50187044