PATENT DOCUMENT

Publication Number: US-12050360-B1
Application Number: US-202117480039-A
Country: US
Kind Code: B1

Title: Induction heating assembled lens unit

Abstract:
A lens assembly includes a stack of thermoplastic lenses that are aligned along a common optical axis and that are interleaved with metallic disks having an open central portion. Peripheral portions of each of the thermoplastic lenses adhere to the interleaved metallic disks to form a fused stack of lenses. A method of making the fused stack of lenses is disclosed and includes subjecting a set of interleaved lenses and metallic disks to an alternating current electromagnetic field that induces eddy currents in the metallic disks, causing heating that melts the adjacent lenses. The melted thermoplastic lens material adheres to adjacent metallic disks. The metallic disks reduce stray light from entering the lens stack, while permitting light to enter central portions of the lenses.

Claims:
What is claimed is: 
     
       1. A lens system, comprising:
 a plurality of lenses assembled coaxially, each lens positioned sequentially along a common optical axis and attached via a melted peripheral portion of the lens to a corresponding disk positioned adjacent to the lens, wherein each lens comprises a central portion that is configured to refract light incident on the lens; and 
 the corresponding one or more disks comprise metal, have a center portion that is open and that permits light to pass through the center portion, and are interleaved with the lenses and coaxial with the lenses, wherein each disk is attached to at least one corresponding adjacent lens of the plurality of lenses at a respective side of the disk via at least some of the melted peripheral portion of the corresponding lens. 
 
     
     
       2. The lens system of  claim 1 , wherein individual ones of the disks are configured to block stray light reflections from propagating through the lenses of the lens system. 
     
     
       3. The lens system of  claim 1 , wherein at least one of the disks comprises aluminum, or stainless steel, or SAS metal. 
     
     
       4. The lens system of  claim 1 , wherein the lenses comprise a thermoplastic material. 
     
     
       5. The lens system of  claim 1 , wherein one or more of the disks includes one or more thermal stress relief gaps. 
     
     
       6. The lens system of  claim 1 , wherein each of the disks has a thickness greater than or equal to 20 microns and less than or equal to 50 microns. 
     
     
       7. The lens system of  claim 1 , wherein each of the disks is configured to heat peripheral portions of a corresponding lens in physical contact with the disk without causing optical distortion of a central portion of the corresponding lens, wherein the central portion of the corresponding lens is configured to refract light. 
     
     
       8. The lens system of  claim 1 , wherein the lens structure has a height that does not exceed 6 mm. 
     
     
       9. A camera, comprising:
 a plurality of lenses assembled coaxially, each lens positioned sequentially along a common optical axis and attached to a corresponding disk positioned adjacent the lens via a melted peripheral portion of the lens, wherein each lens comprises a central portion that is configured to refract light incident on the lens; 
 the corresponding one or more disks comprise metal, have a center portion that is open and that permits light to pass through the center portion, and are interleaved with the lenses and coaxial with the lenses, each disk attached to at least one corresponding adjacent lens of the plurality of lenses at a respective side of the disk via at least some of the melted peripheral portion of the corresponding adjacent lens; and 
 an image sensor configured to receive light refracted from the plurality of lenses. 
 
     
     
       10. The camera of  claim 9 , wherein individual ones of the metallic disks are positioned to block stray light reflections from propagating through the lenses. 
     
     
       11. The camera of  claim 9 , wherein the lenses are mounted in the camera without use of a lens barrel. 
     
     
       12. The camera of  claim 9 , wherein the lenses do not include one or more interlocking structures configured to interlock with a corresponding structure of another lens. 
     
     
       13. The camera of  claim 9 , wherein one or more of the metallic disks includes one or more thermal stress relief gaps. 
     
     
       14. A method, comprising:
 assembling, coaxially along an optical axis, items comprising:
 a plurality of refractive lenses, each lens having two respective sides, and 
 a plurality of metallic disks, each metallic disk having a respective opening that permits light to pass through the opening, wherein individual ones of the disks are interleaved with successive ones of the lenses along the optical axis, 
 wherein a peripheral portion of a corresponding side of each lens is in physical contact with a corresponding side of one of the metallic disks; and 
 
 applying an electromagnetic field to the assembled items that causes inductive heating of the metallic disks, wherein individual ones of the inductively heated metallic disks cause melting of the corresponding peripheral portion of those lenses in physical contact with the inductively heated metallic disk, wherein at least some of the melted peripheral portion of the lenses in physical contact with the metallic disk adhere to the metallic disk. 
 
     
     
       15. The method of  claim 14 , wherein the assembling further comprises:
 placing each of the lenses and each of the metallic disks into an alignment fixture so that within the alignment fixture, successive lenses are separated from one another by a respective metallic disk. 
 
     
     
       16. The method of  claim 15 , further comprising after applying the electromagnetic field, removing from the alignment fixture the assembled items that are adhered. 
     
     
       17. The method of  claim 14 , wherein the applying the electromagnetic field further comprises applying the electromagnetic field for a predetermined period of time. 
     
     
       18. The method of  claim 17 , wherein the predetermined period of time is based at least in part on one or more material properties of one or more of the plurality of refractive lenses. 
     
     
       19. The method of  claim 17 , wherein the predetermined period of time is based at least in part on one or more material properties of one or more of the metallic disks. 
     
     
       20. The method of  claim 14 , further comprising applying a coating to a surface of at least one of the disks, wherein the coating reduces reflectivity to light incident on the surface of the at least one disk.

Description:
This application claims benefit of priority to U.S. Provisional Application Ser. No. 63/083,024, entitled “Induction Heating Assembled Lens Unit,” filed Sep. 24, 2020, and which is hereby incorporated herein by reference in its entirety. 
    
    
     BACKGROUND 
     Technical Field 
     This disclosure relates generally to optical systems, and more specifically to magnification in small form factor cameras and lens systems. 
     Description of the Related Art 
     The advent of small, mobile multipurpose devices such as smartphones and tablet or pad devices has resulted in a need for high-resolution, small form factor cameras that are lightweight, compact, and capable of capturing high resolution, high quality images at low F-numbers for integration in the devices. However, due to limitations of conventional camera technology, conventional small cameras used in such devices tend to capture images at lower resolutions and/or with lower image quality than can be achieved with larger, higher quality cameras. Achieving higher resolution with small package size cameras generally requires use of a photosensor with small pixel size and a good, compact imaging lens system. Advances in technology have achieved reduction of the pixel size in photosensors. However, as photosensors become more compact and powerful, demand for compact imaging lens systems with improved imaging quality performance has increased. Thus, a challenge from an optical system design point of view is to provide an imaging lens system that is capable of capturing high brightness, high resolution images, under the physical constraints imposed by small form factor cameras. 
     SUMMARY 
     Embodiments include an assembled stack of optical lenses that are immobilized with respect to one another. The lenses are interleaved with metallic disks, with each disk having an open central portion that permits incident light to pass through the open portion of the disk and subsequently enter a center portion of a subsequent one of the plurality of stacked lenses. Respective melted peripheral portions of each lens are attached to one or more corresponding interleaved metal disks, and the lenses form a fused lens stack. A corresponding central portion of each lens is configured to refract light entering the lens. 
     Embodiments further include a camera that includes a fused lens stack that refracts light entering the camera. 
     Embodiments further include methods of making a fused lens stack. A plurality of lenses, interleaved with metallic disks, is subjected to a varying electromagnetic field that results in eddy current heating of the metallic disks, and subsequent heating and melting of adjacent thermoplastic lenses at their corresponding peripheral portions. The melted thermoplastic lens material adheres to the respective adjacent interleaved metallic disk(s), resulting in a fused lens stack. 
     This Summary is intended to provide a brief overview of some of the subject matter described in this document. Accordingly, it will be appreciated that the above-described features are merely examples and should not be construed to narrow the scope or spirit of the subject matter described herein in any way. Other features, aspects, and advantages of the subject matter described herein will become apparent from the following Detailed Description, Figures, and Claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    illustrates a portable multifunction device that includes an optical system. 
         FIGS.  2 A and  2 B  provide a side-by-side illustration including an arrangement of immobilized lenses ( FIG.  2 A ), and an arrangement of fused lenses ( FIG.  2 B ) according to an embodiment. 
         FIGS.  3 A,  3 B,  3 C,  3 D,  3 E,  3 F  illustrate various disks and disk portions according to embodiments described herein. 
         FIG.  4    depicts an arrangement of lenses interleaved with metallic disks within a fixture, according to an embodiment. 
         FIG.  5    is an illustration of an apparatus that provides an electromagnetic field for use in forming a fused lens stack, according to embodiments described herein. 
         FIG.  6    illustrates a portion of a lens stack subjected to an electromagnetic field produced by an electrically conducting coil, which is used to make a fused lens stack, according to embodiments described herein. 
         FIG.  7    is a flowchart of a method of making a fused lens stack, according to embodiments described herein. 
         FIG.  8    is a front view illustration of a device that includes a camera employing a lens system as described herein, according to some embodiments. 
         FIG.  9    is a cross-sectional view illustration of a device that includes a camera employing a lens system as described herein, according to some embodiments. 
     
    
    
     This specification includes references to “one embodiment” or “an embodiment.” The appearances of the phrases “in one embodiment” or “in an embodiment” do not necessarily refer to the same embodiment. Particular features, structures, or characteristics may be combined in any suitable manner consistent with this disclosure. 
     “Comprising.” This term is open-ended. As used in the appended claims, this term does not foreclose additional structure or steps. Consider a claim that recites: “An apparatus comprising one or more processor units . . . ”. Such a claim does not foreclose the apparatus from including additional components (e.g., a network interface unit, graphics circuitry, optical sensor, etc.). 
     “Configured To.” Various units, circuits, or other components may be described or claimed as “configured to” perform a task or tasks. In such contexts, “configured to” is used to connote structure by indicating that the units/circuits/components include structure (e.g., circuitry) that performs those task or tasks during operation. As such, the unit/circuit/component can be said to be configured to perform the task even when the specified unit/circuit/component is not currently operational (e.g., is not being electrically powered). The units/circuits/components used with the “configured to” language include hardware—for example, circuits, memory storing program instructions executable to implement the operation, etc. Reciting that a unit/circuit/component is “configured to” perform one or more tasks is expressly intended not to invoke 35 U.S.C. § 112(f), for that unit/circuit/component. Additionally, “configured to” can include generic structure (e.g., generic circuitry) that is manipulated by software and/or firmware (e.g., a field programmable gate array (FPGA) or a general-purpose processor executing software) to operate in manner that is capable of performing the task(s) at issue. “Configure to” may also include adapting a manufacturing process (e.g., a semiconductor fabrication facility) to fabricate devices (e.g., integrated circuits) that are adapted to implement or perform one or more tasks. 
     “First,” “Second,” etc. As used herein, these terms are used as labels for nouns that they precede, and do not imply any type of ordering (e.g., spatial, temporal, logical, etc.). For example, a buffer circuit may be described herein as performing write operations for “first” and “second” values. The terms “first” and “second” do not necessarily imply that the first value must be written before the second value. 
     “Based On.” As used herein, this term is used to describe one or more factors that affect a determination. This term does not foreclose additional factors that may affect a determination. That is, a determination may be solely based on those factors or based, at least in part, on those factors. Consider the phrase “determine A based on B.” While in this case, B is a factor that affects the determination of A, such a phrase does not foreclose the determination of A from also being based on C. In other instances, A may be determined based solely on B. 
     DETAILED DESCRIPTION 
     Embodiments of lens systems are described that may, for example, be used in small form factor systems, such as a camera within a cellular telephone. In embodiments, a lens system may be formed that does not require an external barrel, e.g., for mechanical support that maintains relative positions of a plurality of lenses. Elimination of the external barrel can reduce an outer diameter of the lens system, which enables the lens system to occupy less “real estate” on the face of a device (e.g., cell phone) in which the lens system is placed as part of a camera within the device, and may also reduce an overall height of the lens system. 
     In embodiments, a fused lens stack is made by placing thermoplastic lenses, interleaved with metallic disks (also “metallic rings” herein), into a fixture (also “jig” herein). The metallic disks may include an open portion (e.g., the metallic disk may completely, or at least partially, surround a hole, which hole may be any of a plurality of shapes such as circular, polygonal, elliptical, oval, or another shape), and are in physical contact with radially peripheral portions of corresponding lens(es), e.g., at a peripheral (outer) portion of a radius of a lens. In embodiments, the metallic disks are shaped so as to avoid physical contact with central (e.g., center) portions of the lenses. Avoidance of physical contact with the central portions of the lenses minimizes possible distortion of the central portion of one or more lenses, due to heat conduction from a metallic disk that is heated, e.g., by induction heating, in order to fuse the lens stack. The fixture, within which the interleaved lenses and metallic disks are placed, maintains relative positions of the lenses and the metallic disks with respect to one another prior to induction heating. After loading the jig with the lenses and metallic disks, the loaded jig is subjected to an alternating current electromagnetic field. The electromagnetic field causes eddy current induction heating of each of the metallic disks, and the heat generated causes melting of the peripheral portions of the adjacent lenses that are in physical contact with the corresponding disk, which results in adhesion of the melted peripheral portions of each lens to the adjacent metallic disk. The amount of heat to be generated is such that there is substantially no resulting adverse effect on optical properties of an interior portion (e.g., central portion) of each of the lenses, so that after the lens stack is fused into an unarticulated fused lens stack, the individual lenses continue to refract light with the same optical properties that each lens exhibited prior to the lens stack being subjected to the electromagnetic field. 
     In embodiments, the electromagnetic field has a predetermined field strength and a predetermined frequency, and the fixture may be subjected to the electromagnetic field for a predetermined amount of time. One or more of the field strength, frequency or amount of time may be determined based in part upon properties of the disks including electrical and electromagnetic properties (e.g., electrical conductivity, magnetic permeability, etc.), thermal conduction properties of the disks, and/or other material properties of the disks. For example, one or more of the electromagnetic field strength, the frequency of the electromagnetic field, or the period of time during which the stack of lenses and disks are subjected to the electromagnetic field, may be selected based on a steady state or instantaneous temperature reached by one or more of the disks and thermal conduction properties of the disks, and may also be selected based in part upon a melting temperature and/or thermal conduction properties of the thermoplastic lenses. 
     Fusion of the lenses by means of induction heating of the metallic disks interleaved with the lenses may maintain localization of the heating of adjacent lenses at peripheral portions of the lenses, so that a central portion of each lens is not deformed due to the inductive heating of the metallic disks. Thus, the lenses of the lens stack may be fused without adversely affecting optical properties (e.g., refraction of light) for the central portions of the lenses. Because no melting or adverse distortion of the central portions of corresponding lenses occurs due to induction heating of the metallic disks, the optical properties of the central portions of the lenses, including refractive properties, are essentially unchanged (e.g., not adversely affected) after the heating and consequent adhesion of the lenses to one or more corresponding metallic disks, as compared with the optical properties of the central portions of the lenses prior to the heating and adhesion of the lenses to the corresponding metallic disk(s). 
     The metallic disks may serve an additional function after the fusing is complete: one or more of the metallic disks may block some extraneous light from entering the lenses (e.g., entering at peripheral portions of the lens stack along skewed directions). Blocking unwanted extraneous light from entering the lens stack may result in improved (e.g. sharpened) image formation and improved contrast, e.g., when used in a camera such as a camera within a cellular telephone. In embodiments, some or all of the metallic disks may be coated (e.g., blackened) to reduce reflectivity of light that might otherwise enter the lens stack, e.g., at a skewed angle with respect to the common optical axis of the lens stack. 
     A fused lens stack, as described in various embodiments herein, may exhibit improved reliability, e.g., with regard to an unexpected impact to the lens combination, such as an accidental drop or impact with a hard surface, in comparison with other arrangements that immobilize a set of lenses with respect to one another. For example, an arrangement, such as will be discussed with regard to  FIG.  2 A , features a plurality of lenses immobilized within a housing (“lens barrel”), including use of a retainer ring. If a camera containing the lens barrel were to be accidentally dropped onto pavement or impacted against another hard object, the resulting impact could jar the retainer ring to “pop out” of its intended position. As a result, the lenses could fall out of the lens barrel and could break, or become scratched. 
     In contrast, for the immobilized (“fused”) lens stack described herein in various embodiments (e.g.,  FIG.  2 B ), the plurality of lenses are immobilized with respect to one another by attachment, to interleaved disks, of successive lenses made of one or more thermoplastic materials (e.g., made using the induction heating techniques described herein), without use of a retainer ring or lens barrel. A physical impact, with a hard surface, of the fused stack of lenses may be less likely to result in separation of the lenses than a physical impact with a hard surface, of the lens stack of  FIG.  2 A . A fused lens stack made according to embodiments described herein, may be installed in, e.g., a cellular telephone, with smaller chance that an impact to the cellular telephone would destroy the lens stack, than with a lens stack held together mechanically, such as the lens stack of  FIG.  2 A . 
     Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. However, it will be apparent to one of ordinary skill in the art that some embodiments may be practiced without these specific details. In other instances, methods, procedures, components, circuits, and networks have not been described in detail so as not to unnecessarily obscure aspects of the embodiments. 
       FIG.  1    illustrates a portable multifunction device  100 , according to some embodiments. Device  100  may be, e.g., a cellular telephone, tablet, mobile multifunction device, or other mobile electronic device. On a front face of the device  100 , a notch  110  having a notch height  130  permits light to enter a camera module  120  located internally to the device  100 . The camera  120  has an entrance diameter less than or equal to the notch height  130 . From a point of view of use of surface area (“real estate”) on the face of the device  100 , it may be advantageous for the notch  110  to be as small as possible, while permitting the camera module  120  to function as intended. The size of the notch  110  including the notch height  130  may be at least partially dictated by the size of the camera module  120 . Reducing the size of the camera module  120  may allow the size of the notch  110 , including the notch height  130 , to be decreased. Embodiments described herein for a fused lens stack may allow for a smaller diameter lens stack, which may in turn permit a decrease in the size of the camera module  120  that includes the lens stack, which consequently may allow for a smaller notch  110  on the front face of the device  100  than, e.g., a lens stack within a lens barrel. 
       FIG.  2 A  illustrates a set of lenses  214 ,  216 ,  218 ,  220 ,  222  assembled according to one methodology. The set of lenses are maintained within a lens barrel  202  using a retainer ring  204 , which may be, e.g., spring-loaded or compression fit to maintain its position relative to the lens barrel  202 , or may snap into a groove of the lens barrel,  202 , or placed via another technique to substantially immobilize the retainer ring  204  within the lens barrel  202  and hold the lenses in place. Each of the lenses, or only some of the lenses, may be attached to one another via use of interlocking structures. For example, in  FIG.  2 A  interlocking structure  206  (circled to highlight and indicate location of the interlocking structure) and interlocking structure  208  are between adjacent lenses  220  and  222 , and interlocking structures  210 ,  212  are between adjacent lenses  220  and  218 . In some embodiments (not shown), there may be interlocking structures between each adjacent pair of lenses. The interlocking structures used to immobilize adjacent lenses with respect to each other (e.g., mating portions of adjacent lenses, or other adjacent interlocking structures) add material to a peripheral portion of each lens that is to be interlocked with an adjacent lens. Therefore an overall size (e.g., diameter) of each interlocking lens would be larger than without inclusion of the interlocking structure, which in turn would increase an overall size of the assembly in comparison to a lens stack without interlocking structures. 
     The lens barrel  202  serves to maintain relative positions of the lenses  214 ,  216 ,  218 ,  220 ,  222 . The lens barrel  202  adds to the overall size (e.g., diameter and height) and mass of the assembly. If an assembly such as  200  is utilized in a camera assembly such as the camera assembly  120  of  FIG.  1   , the notch  110  would need to be large enough to accommodate the outer dimensions of the lens barrel  202 , e.g. diameter  260 , and the thickness of the device  100  would need to be large enough to accommodate the height  262  of the lens barrel  202 . 
       FIG.  2 B  illustrates an embodiment in which lenses  224 ,  226 ,  228 ,  230 , and  232  are stacked and interleaved with metallic disks  234 ,  236 ,  238 ,  240 , and also including disk  242  that is optionally metallic. The metallic disks may be fabricated from any of various metals that produce eddy current heating when subjected to an electromagnetic field (e.g., aluminum, stainless steel, SAS, other ferromagnetic metals, etc.). The metallic disks may be circular, polygonal, elliptical, oval, etc. in general shape, and have an open center region, permitting light to pass through the center region (e.g., “donut-shaped” or substantially donut-shaped). The metallic disks are substantially opaque. In some embodiments, one or more of the metallic disks  234 ,  236 ,  238 ,  240 , and  242  have one or more openings (e.g., gaps, slits) in body of the disk that serve a thermal stress reduction function, which is illustrated in  FIG.  3   . In embodiments, one or more of the metallic disks  234 ,  236 ,  238 ,  240 , and  242  are darkened, such as coated or painted with a dark (e.g., black), or otherwise opaque material. The opaque regions may prevent some light (e.g., stray light having a substantial angle of incidence with respect to an optical axis of the coaxial lenses) incident on the metallic disk from passing through to peripheral regions of a subsequent lens within the set of lenses, without blocking light entering a central portion of the metallic disk (e.g., entering at a small angle to the optical axis) and subsequently continuing through to enter a central portion of any of the lenses. 
     In contrast to the arrangement of lenses depicted in  FIG.  2 A  that includes lens barrel  202 , the lens stack of  FIG.  2 B  does not have a lens barrel. As indicated above, the lens barrel  202  of  FIG.  2 A  adds to an overall diameter  260  of the lens arrangement  200 , and may add to an overall height  262  of the arrangement  200 . In further contrast to the arrangement of lenses illustrated in  FIG.  2 A , the lens stack of  FIG.  2 B  has no interlocking structures (e.g.,  206 ,  208 ,  210 ,  212  of  FIG.  2 A ) between several of the lenses. The lens stack of  FIG.  2 B  does not use, or need a lens barrel or interlocking structure(s) that serve to immobilize the lenses with respect to each other. Instead, the lenses of  FIG.  2 B  are fused to one another, and do not need a lens barrel to immobilize the lenses with respect to one another. Further, because the lenses of  FIG.  2 B  are affixed to one another due to melting and fusing of an outer portion of the lenses, there is no need for interlocking structures such as  206 ,  208 ,  210 ,  212  in  FIG.  2 A , which interlocking structures serve to immobilize adjacent lenses with respect to one another. 
     In contrast to the lens arrangement  200  depicted in  FIG.  2 A , in  FIG.  2 B  each lens of the lens stack  250  is fused by induction heating of the metallic disks, described in detail herein with regard to  FIGS.  5 - 7   . An inductively heated metallic disk causes melting of adjacent thermoplastic lens(es) in physical contact with the heated metallic disk, and the melted thermoplastic adheres to the metallic disk (for interior lenses, on each side to a respective metallic disk). In embodiments, one or more of the lenses may be fused on at least one side to an adjacent lens, or each of the sides (e.g., interior lenses) may be fused to a respective adjacent lens, e.g., the thermoplastic lens material may flow around (or through thermal expansion gaps in the metallic disks) and become attached to the adjacent lens. Thus, the lenses of lens stack  250  are maintained fixed in position with respect to each other via melted thermoplastic as a result of an induction heating process described in detail in  FIGS.  4 - 7   . In embodiments, disk  242  may be metallic or non-metallic. Disk  242  may serve as an aperture to the lens stack of  FIG.  2 B  that limits incoming light. In embodiments, disk  242  serves as an aperture to the lens stack of  FIG.  2 B . In comparison, the lens barrel  202  of  FIG.  2 A  forms aperture  223  that limits incoming light to the lens stack of  FIG.  2 A , and the aperture  223  of the lens barrel  202  may occupy more space than, e.g., disk  242  used as an aperture in  FIG.  2 B . 
     The fused lens stack  250  depicted in  FIG.  2 B  does not have a retainer ring, or a lens barrel, or interlocking structures, and therefore an outside diameter  270  may be smaller than an outside diameter  260  of the lens barrel  202 . A camera that employs the fused lens stack  250  therefore can function with a smaller notch (e.g., notch  110  of  FIG.  1   ) on a front face of a device (e.g., the device  100  of  FIG.  1   ) than a camera with a lens stack within a lens barrel  202 . That is, a notch through which a camera with the fused lens stack  250 , receives light, would occupy a smaller footprint on the face of a device than an notch that accommodates a camera with a lens barrel  202 . A smaller notch is advantageous in overall design and construction of the device, as it allows for more surface area (“real estate”) of the front surface of the device to be utilized for other purposes, e.g., display screen size. In embodiments, the fused lens stack  250  has a height  280  that does not exceed 6 mm, and in embodiments the height  280  may be less than the height of the lens barrel  262  and lens stack of  FIG.  2 A . 
       FIG.  3 A ,B,C,D,E,F illustrate various geometric shapes of disks (also “metal shields,”) and portions of disks that may be part of a fused lens stack, such as the fused lens stack illustrated in  FIG.  2 B . In embodiments, the metallic disks ( 310 ,  320 ,  330 ) surround or partially surround a respective open center portion ( 304 ,  324 ,  334 ) that permits light to pass through from one side of the metallic disk to another side of the metallic disk. In embodiments, an exterior boundary ( 302 ,  322 ,  332 ) of each respective metallic disk ( 310 ,  320 ,  330 ) may be circular or non-circular, e.g., circular, polygonal (e.g., square, hexagonal, octagonal, etc.), elliptical, oval-shaped, or another shape, and a respective interior boundary ( 308 ,  328 ,  338 ) of the respective open center ( 308 ,  328 ,  338 ) of the metallic disk may be shaped as a circle, polygon (e.g., square, hexagon, octagon, etc.), ellipse, oval, or another shape. In embodiments, the disks have a thickness between 20-50 microns; however, in other embodiments, metallic disks may be employed with thicknesses that are less than 20 microns, or greater than 50 microns. In an embodiment, metallic disks in an assembly of stacked lenses (e.g.,  FIG.  4 ,  400   ) have a same thickness. In other embodiments, the thicknesses of various ones of the metallic disks may differ from one another. Metallic disk  310  has a gap  306 . Metallic disks  320 ,  330  have one or more slits (e.g.,  326 ,  336 ) that may provide thermal stress relief, e.g., the gap or slits may permit the metallic disks to expand or contract during induction heating without causing long-term (e.g., permanent or otherwise of long duration) physical deformation of the metallic disks. As shown, metallic disk  320  has 8 slits notched from the interior portion  324 , and metallic disk  330  has 8 slits notched from the outer periphery  332 . In other embodiments the slits may have a different shape, e.g., arc-shaped, or other shapes. In other embodiments, one or more of the metallic disks are shaped as solid disks without gap or slits, and with an open center portion (e.g., donut-shaped). 
       FIG.  3 D  depicts an embodiment  340  that includes two metallic portions  342 ,  346 . An open interior portion  344  permits incident light to pass through from one side of the embodiment to another side of the embodiment. The embodiment  340  may be used, e.g., in the assembly of  FIG.  4    (described below), replacing one or more of the disks  410 ,  414 ,  418 ,  422 ,  426  that, when subjected to a varying electromagnetic field, experiences eddy current induction heating in the portions  342 ,  346  that can melt thermoplastic material (e.g., thermoplastic lens(es) or another interleaved plastic layer) in physical contact with a portion of the embodiment  340 . 
       FIG.  3 E  depicts an embodiment  350  that includes four metallic portions  352 ,  354 ,  356 ,  358 . An open interior portion  359  permits incident light to pass through from one side of the embodiment to another side of the embodiment. The embodiment  350  may be used, e.g., in the assembly of  FIG.  4    (described below), replacing one or more of the disks  410 ,  414 ,  418 ,  422 ,  426  that, when subjected to a varying electromagnetic field, experiences eddy current induction heating in the portions  352 ,  354 ,  356 ,  358  that can melt thermoplastic material (e.g., thermoplastic lens(es) or another interleaved plastic layer) in physical contact with a portion of the embodiment  350 . Other embodiments are contemplated with more, or less metallic elements that surround an open portion (e.g.,  359 ) that permits light to pass through. The embodiments shown and described are nonlimiting. 
       FIG.  3 F  depicts an embodiment  360  that includes two metallic rings  362 ,  366 , separated by a non-metallic, non-electrically conductive portion  366 . An open interior portion  368  permits incident light to pass through from one side of the embodiment to another side of the embodiment. The embodiment  360  may be used, e.g., in the assembly of  FIG.  4    (described below), replacing one or more of the disks  410 ,  414 ,  418 ,  422 ,  426 . When the embodiment  360  is subjected to a varying electromagnetic field, the rings  362 ,  366  experience eddy current induction heating that can melt thermoplastic material (e.g., thermoplastic lens(es) or another interleaved plastic layer) in physical contact with a portion of the embodiment  350 . Other embodiments are contemplated in which a disk may comprise metallic portions and non-metallic portions that surround an open portion (e.g.,  368 ) that permits incident light to pass through. The embodiments shown and described are nonlimiting. 
     In embodiments, one or more of the embodiments  310 - 360  in an assembly, such as the lens stack  250  shown in  FIG.  2 B , is darkened (e.g., blackened), such as by coating the disk or painting the embodiment with a dark paint, which may reduce or prevent reflections of light that may otherwise result in reduction of clarity or contrast of an otherwise refracted image of light that enters the lens stack  250 . 
     As explained above with regard to  FIG.  2 B  and below with regard to  FIG.  4   , and in further detail below with regard to  FIGS.  5 - 7   , as a result of induction heating of the metallic disks the melted plastic, e.g., from the adjacent lens(es) (or other adjacent plastic layer) in physical contact with a metallic disk, may adhere to the metallic disk, enhancing rigidity of the lens stack after induction heating is completed. Additionally, metallic disks with gaps (e.g., thermal expansion gaps, as in metallic disks  310 ,  320 ,  330 ) may permit some of the melted plastic of an adjacent thermoplastic lens to flow through the gap(s) and/or to flow around an outer extent of the metallic disk, and adhere to another adjacent thermoplastic lens at a peripheral portion of the adjacent lens, resulting in fusion of peripheral portions of the adjacent lenses. 
     In other embodiments (not shown), an assembly that includes lenses interleaved with disks or other embodiments shown in  FIGS.  3 A- 3 F , may also be interleaved with layers of a meltable layer (e.g., meltable plastic) that are in physical contact with respective disks or embodiments shown in  FIGS.  3 A- 3 F . When subjected to a varying electromagnetic field, the disks or embodiments of  FIGS.  3 A- 3 F  may experience induction eddy current heating that causes, by thermal conduction with adjacent plastic layer(s), melting of the interleaved meltable plastic, and the melted plastic may adhere to the metallic elements that have been inductively heated. In such embodiments, although the lenses may or may not be fabricated from a thermoplastic material, each of the plastic layers, may also adhere to a corresponding adjacent lens in physical contact with the melted plastic layer. In such embodiments, some or all of the lenses may be fabricated from another optical material, e.g. plastic, glass, etc. that may have a higher melting temperature. However, fusing of the lens stack can occur due to the melting of the interleaved plastic layers and adhesion to adjacent metallic and non-metallic (e.g., lens) surfaces in physical contact with the melted plastic layers. 
       FIG.  4    illustrates an assembly  400  that includes a fixture  402  (“jig”), which may be, e.g., cylindrical in shape (or a different geometrical shape, e.g., polygonal, elliptical, etc.), the fixture  402  containing a set of lenses interleaved with metallic disks or the embodiments depicted in  FIGS.  3 A-F , according to an embodiment. The fixture  402  serves to immobilize the set of lenses with respect to one another, and with respect to the interleaved metallic disks. The fixture  402  is typically fabricated from an electrically non-conductive medium. In other embodiments (not shown), the lenses and metallic disks or embodiments depicted in  FIGS.  3 A-F , may also be interleaved with meltable layers, e.g., meltable plastic. 
     In the following description, a disk may be replaced by one of the embodiments shown in  FIGS.  3 A-F . In an embodiment, the assembly  400  may be assembled as follows: A first disk  410  is placed into the fixture  402 . Subsequently a first lens  412  is placed into the fixture  402 . After each lens  412 ,  416 ,  420 ,  424 , is placed into the fixture  402 , a corresponding metallic disk ( 414 ,  418 ,  422 ,  426 ) whose outside diameter is approximately the outside diameter of the previously placed lens, is placed into the fixture. In an embodiment, some or all of the metallic disks may have the same or similar outside diameter. In an embodiment, lens diameters of the lenses placed in the fixture  402  increase with each successive lens placed into the fixture  402 , and diameters of disks ( 410 ,  414 ,  418 ,  422 ,  426 ) increase for each successively placed metallic disk. The largest of the lenses  428  is then placed in the fixture  402 . 
     In some embodiments, the fixture  402  may be made up from several portions that are detachable, e.g., to promote disengagement of the lens stack after induction heating is complete, after which the lenses are fused to each other and adhere to the interleaved metallic disks. 
       FIG.  5    illustrates an apparatus  500  that may be employed to produce electromagnetic induction heating in a stack of lenses within an assembly of lenses and metallic disks, such as the assembly illustrated in  FIG.  4   . The apparatus  500  includes a high frequency power source  510 , a resonant circuit  512 , a control system  514 , and an electrical coil  520  that provides an alternating current electromagnetic field within which the fixture/assembly is immersed. In embodiments, typical frequencies used in the induction heating apparatus are 200-300 kHz. In other embodiments, other frequencies may be used in the induction heating process. The chiller  508 , controlled by the control system  506 , provides cooling to the electrical coil  520 , e.g. via an external jacket (not shown) that coaxially surrounds the coil  520 . In other embodiments (not shown), the electrical coil  520  may be embedded within the fixture  402  that supports each of the lenses and metallic disks of the assembly of lenses and metallic disks. In other embodiments, the electrical coil  520  may be embedded within a holder (not shown) that surrounds the fixture  402 . Whether embedded within the fixture  402 , or surrounding the fixture  402 , the stack of lenses and metallic disks is surrounded by the electrical coil  520  and the stack of lenses and metallic disks configured to be immersed in an electromagnetic field produced when high frequency, alternating current (AC) is supplied to the electrical coil  520  from the combination of power source  510  and resonant circuit  512 . 
     The electromagnetic field produced by the coil  520  causes electromagnetic induction eddy current heating to occur in each of the metallic disks of the assembly  502  (shown in cross sectional view). Heat from each metallic disk may be transferred through physical contact (via thermal conduction) to the adjacent lens(es), which lenses are typically constructed from a thermoplastic material. Heating of the peripheral portions of the adjacent lens(es) may cause portions of the peripheral portions of the adjacent lens(es) to melt and adhere to the metallic disk to which the adjacent lens is in physical contact. Additionally, some portion of melted plastic from the adjacent lens(es) may pass through the one or more thermal expansion gaps in the metallic disk (see  FIG.  3   ), and/or around a periphery of the adjacent metal disk, and fuse with an adjacent lens on an opposite side of the metallic disk. As a result, the adjacent lenses that are separated by one of the metallic disks adhere to the metallic disk and to a subsequent lens, forming a fused mechanical connection between adjacent lens(es), and between each lens and its adjacent metallic disk(s). 
     It is to be noted that, for each of the lenses, heating is limited to a peripheral portion of the lens that is in physical contact with the corresponding metallic disk. For example, metallic disk  530  is in physical contact with peripheral portion  542  of lens  540  (shown in cross sectional view). A central portion  544  of the lens  540  has no physical contact with the metallic disk  530 . During induction current heating of the metallic disk via the electromagnetic field provided by the coils  520 , the peripheral portion  542  of the lens  540  will receive heat, via thermal conduction, from the metallic disk  530  in physical contact with the peripheral portion  542 , while the central portion  544  of the lens  540  remains substantially unheated because the central portion  544  is not in physical contact with the metallic disk  530 . Therefore, the central portion  544  of the lens  540  will be unaffected (e.g., undistorted) by the heat transferred to the peripheral portion  542 . After the induction heating is complete, the central portion  544  will maintain the same optical properties, e.g., refractive properties, as the central portion  544  prior to the induction heating, and will consequently provide the refraction intended for the lens  540  included in the lens stack. Similar considerations apply to each of the lenses of the lens stack: the central portion of each lens is substantially unaffected by the heat transferred to the peripheral portion of the lens that is in physical contact with a corresponding metallic disk. Hence, optical properties of the central portion of each lens are unaffected by the heat transferred to the corresponding peripheral portion, and therefore optical properties of the central portion of each lens remains unchanged from the optical properties of the central portion of the lens prior to induction heating of the lens stack. 
       FIG.  6    depicts a portion  600  of apparatus  500 . Apparatus  600  includes an electrically conductive coil  610  that produces an electromagnetic field  602  employed to fuse a lens stack by induction heating, according to embodiments. The electrically conductive coil  610  carries a high frequency alternating current (indicated by double arrow  612 ), which in turn produces the electromagnetic field  602 . An assembly, such as assembly  400  of  FIG.  4   , is placed within an interior space defined by the coil  610 , and is subject to the electromagnetic field  602 .  FIG.  6    illustrates a portion of the assembly of  FIG.  4   , including lenses  620  and  640  and metallic disk (metallic shield)  630  situated between the lenses  620  and  640 . 
     The electromagnetic field  602  causes induction eddy currents  632  and  634  (each depicted with two arrows to indicate alternating direction of eddy current) to flow within the interleaved metallic disk  630 . Heat generated by the eddy currents  632 ,  634  results in heated portions  636 ,  638  of the metallic disk  630 . The heat within the heated portions  636 ,  638  may be conducted to adjoining thermoplastic lenses  620 ,  640  that are in physical contact with the metallic disk  630 . The metallic disk  630  is open (e.g., “donut-shaped” or near donut-shaped as in  310  of  FIG.  3   ) at a center portion (not shown) of the metallic disk  630 , and the metallic disk  630  is in physical contact with the adjoining thermoplastic lenses  620 ,  640  at their respective peripheral portions. Due to the geometry of the metallic disk  630  (e.g., no metal in the center portion of the disk  630 ), there is no physical contact between the metallic disk  630  and corresponding center/central portions of the lenses  620 ,  640 . Thermal conduction occurs between the heated portions  636 ,  638  of the metallic disk  630 , and corresponding peripheral portions of the lenses  620 ,  640  that are in physical contact with the metallic disk  630 . 
     As a result of the heat received by thermal conduction from the metallic disk  630 , thermoplastic lenses  620 ,  640  melt at corresponding lens peripheral portions of the lenses  620 ,  640 , and melted thermoplastic from each of the lenses  620 ,  640 , adheres to the metallic disk  630  at a corresponding side of the metallic disk  630  that is in physical contact with the respective one of the lenses  620 ,  640 . In embodiments, some portion of the melted thermoplastic may flow around the metallic disk  630  and/or may flow through thermal stress relief gaps (e.g., as in  FIG.  3   , but not shown in  FIG.  6   ) in the disk  630 , and that portion of melted thermoplastic may fuse with the peripheral portion of the lens adjacent to the metallic disk  630  on an opposite side of the metallic disk  630 . 
     Thus lens  620 , metallic disk  630 , and lens  640  are fused together. Referring again to  FIGS.  4  and  5   , in similar fashion to the description above of fused lenses of  FIG.  6   , the lens stack  400  is fused by subjecting the lens stack  400  to an electromagnetic field produced in the apparatus  500  to produce an unarticulated lens stack that includes lenses ( 412 ,  416 ,  420 ,  424 ,  428 ) and the interleaved disks ( 410 ,  414 ,  418 ,  422 ,  426 ). (It is noted that in an embodiment, the disk  410  may be non-metallic, and may be placed in front of the fused lens stack and serve to limit light entering the fused lens stack). The fused lens stack is subsequently removable from the external fixture  402  of  FIG.  4   , and is unarticulated and mechanically stable. 
     In another embodiment (not shown), any of the embodiments of  FIGS.  3 A-F  may be substituted for any of the interleaved disks  410 ,  414 ,  418 ,  422 ,  426 . When the assembly is subjected to a varying electromagnetic field (similar to  FIGS.  5  and  6   ), induction heating of the metallic portions results, and some of the heat generated may be transferred to adjacent layers in physical contact with the metallic portions. Melting of a meltable material of an adjacent layer in contact with a metallic portion may occur. The melted material may be, e.g., melted thermoplastic of an adjacent lens, or melted plastic of an interleaved (e.g., non-lens) plastic layer, etc. The melted material may adhere to the metallic portion (and may adhere to nearby layers, e.g., if the melted plastic drips through a gap or slit, or around the heated metallic portion), which can result in fusing of the assembly. 
       FIG.  7    is a flow diagram of a method  700  of making a fused lens stack, according to embodiments. At block  710 , a lens (e.g., a thermoplastic lens or other material that may be melted by heat) is placed in a fixture that may be used to align a plurality of interleaved lenses and metallic disks. Proceeding to block  720 , a metallic disk is placed in the fixture so that the metallic disk is in physical contact with the previously placed lens at a peripheral portion of the previously placed lens. 
     Advancing to decision diamond  730 , if there are additional lenses to be placed in the fixture, (a total number of lenses is at least two), the method returns to block  710  and a next lens is placed in the fixture. The next lens may contact the previously placed metallic disk at the periphery of the next lens. Proceeding to block  720 , another metallic disk is placed in the fixture, contacting the previously placed lens. 
     Advancing to decision diamond  730 , when all lenses have been placed in the fixture, moving to block  740  the assembly of lenses and interleaved metallic disks in the fixture is placed in an electromagnetic induction apparatus. Proceeding to block  750 , the lens stack is subject to a varying (e.g. alternating current) electromagnetic field for a predetermined length of time, at a predetermined frequency with a predetermined current flow (electric power), causing induced eddy currents to flow in the metallic disks that result in induction heating of the metallic disks. Heat from the metallic disks flows to peripheral portions of the adjacent lenses in physical contact with the respective disk and causes the peripheral portions of the lenses to melt, while central portions of the lenses are essentially unaffected by the heat and maintain optical characteristics to refract incident light as the lenses refracted prior to the induction heating of the lens stack. The melted portions of each lens adheres to the lens and to the metallic disk with which the lens is in physical contact, and the melted lens material may also optionally flow through gaps in the metallic disks and around the periphery of the metallic disks to fuse with adjacent lenses, forming a fused lens stack. Continuing on to block  760 , after the lens stack has cooled sufficiently, the fused lens stack may be removed from the fixture. The method ends at  770 . 
       FIG.  8    illustrates an example portable multifunction device  800  that may include a camera  864  that includes a fused lens stack as described herein, e.g., with reference to  FIGS.  1 - 7   . The camera  864  is configured to receive light through a notch  820 . The notch  820  is similar in function to the notch  110  depicted in  FIG.  1    and as described above, the notch  820  permits light to be received by a camera such as camera  864 . Use of the lens stack, constructed as described in  FIGS.  1 - 7   , may permit the notch  820  of the device  800  to occupy a smaller area (“less real estate”) on a face of the device  800  than if a camera employing a lens stack with a lens barrel (e.g., as shown in  FIG.  2 A ) were to be installed in the device  800  instead of the camera  864 . For example, by employing, in the camera,  864  a fused lens stack as described in embodiments herein, a height dimension  830  of the notch  820  may be smaller than a height dimension of a notch needed to accommodate a camera that employs a lens stack with a lens barrel such as the lens barrel  202  of  FIG.  2 A . 
     The device  800  may have a touch screen  814 . A smaller notch  820  affords additional surface area for the touch screen  814 . The touch screen  814  may display one or more graphics within user interface (UI)  800 . In the embodiment depicted in  FIG.  8   , a user may select one or more of the graphics by making a gesture on the graphics, for example, with one or more hands  802  (not drawn to scale in the figure) or one or more styluses  803  (not drawn to scale in the figure). 
     Device  800  may also include one or more physical buttons, such as “home”  804  or menu button (not shown). The menu button may be used to navigate to any application in a set of applications that may be executed on device  800 . Alternatively, in some embodiments, the menu button is implemented as a soft key in a graphical user interface (GUI) displayed on touch screen  814 . 
     In one embodiment, device  800  includes touch screen  814 , menu button, push button  806  for powering the device on/off and locking the device, volume adjustment button(s)  808 , Subscriber Identity Module (SIM) card slot  810 , head set jack  812 , and docking/charging external port  824 . Push button  806  may be used to turn the power on/off on the device by depressing the button and holding the button in the depressed state for a predefined time interval; to lock the device by depressing the button and releasing the button before the predefined time interval has elapsed; and/or to unlock the device or initiate an unlock process. In an alternative embodiment, device  800  also may accept verbal input for activation or deactivation of some functions through microphone  813 . 
     It should be noted that, although many of the examples herein are given with reference to optical sensor(s)/camera(s)  864  (on the front of a device), one or more rear-facing cameras or optical sensors that are pointed opposite from the display may be used instead of, or in addition to, the optical sensor(s)/camera(s)  864  on the front of the device  800 . 
       FIG.  9    illustrates a device  900  (e.g., a cellular telephone) that includes an optical system  902  such as a camera, range-finding mechanism, etc. The optical system  902  includes a fused lens stack  910 , such as is described in  FIGS.  1 - 7   , and an optical sensor  920 . Other components of the optical system  902  are omitted for clarity. Incident light  940  may enter the optical system  902  through an opening that spans a distance  930 . Because the fused lens stack  910  does not include a lens barrel (shown as  202  in  FIG.  2 A ), the distance  930  is smaller than would be needed to accommodate a lens stack with a lens barrel. The fused lens stack  910  includes metallic disks, and includes (metallic or non-metallic) disk  950  that is opaque and at least partially blocks some light from entering the lens stack  910 , e.g., at a large skewed angle with respect to an optic axis, which optic axis is coincident with incident light  940 . 
     Various modifications and changes to the apparatuses described herein may be made as would be obvious to a person skilled in the art having the benefit of this disclosure. The various embodiments described herein are meant to be illustrative and not limiting. The order of the blocks of the method described in  FIG.  7    may be changed, and various elements may be added, reordered, combined, omitted, modified, etc. Many variations, modifications, additions, and improvements are possible. Accordingly, plural instances may be provided for components described herein as a single instance. Boundaries between various components, operations and data stores are somewhat arbitrary, and particular operations are illustrated in the context of specific illustrative configurations. Other allocations of functionality are envisioned and may fall within the scope of claims that follow. Finally, structures and functionality presented as discrete components in the example configurations may be implemented as a combined structure or component. These and other variations, modifications, additions, and improvements may fall within the scope of embodiments as defined in the claims that follow.

Metadata:
Filing Date: 20210920
Publication Date: 20240730
Grant Date: 20240730
Priority Date: 20200924
Inventors: SHIGEMITSU, NORIMICHI
SCEPANOVIC, MISHA
WEBSTER, STEVEN
Assignee: APPLE INC
CPC Classifications: [{"code": "B29C65/7841", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C65/3668", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C66/1122", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C66/543", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29K2705/12", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29K2705/02", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C65/3644", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C65/3676", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29L2011/0016", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C66/73921", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B13/001", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29D11/00403", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02B5/003", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02B1/041", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B5/005", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02B27/0018", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02B7/021", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02B5/003", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02B5/005", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02B1/041", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B27/0018", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C65/002", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C65/02", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B13/001", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29D11/00403", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29K2701/12", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02B7/021", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02B27/0018", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02B5/005", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02B5/003", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29K2701/12", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29D11/00403", "inventive": false, "first": false, "tree": "[]"}, {"code": "B29C65/002", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02B13/001", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B1/041", "inventive": true, "first": false, "tree": "[]"}, {"code": "B29C65/02", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B7/021", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 91965766