Patent ID: 12204164

DETAILED DESCRIPTION

Various technologies pertaining to a camera module that is well-suited for inclusion in a camera enclosure are now described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more aspects. It may be evident, however, that such aspect(s) may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate describing one or more aspects. Further, it is to be understood that functionality that is described as being carried out by certain system components may be performed by multiple components. Similarly, for instance, a component may be configured to perform functionality that is described as being carried out by multiple components.

Moreover, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or.” That is, unless specified otherwise, or clear from the context, the phrase “X employs A or B” is intended to mean any of the natural inclusive permutations. That is, the phrase “X employs A or B” is satisfied by any of the following instances: X employs A; X employs B; or X employs both A and B. In addition, the articles “a” and “an” as used in this application and the appended claims should generally be construed to mean “one or more” unless specified otherwise or clear from the context to be directed to a singular form.

Described herein is a camera module that is configured to be fixed to a mounting surface (e.g., a chassis) of a camera enclosure, such that an alignment between an optical axis of a lens barrel and an image sensor of an image sensor board remains fixed over time. The camera module described herein is well-suited for use in a smart artificial intelligence (AI) camera that performs distortion correction on images captured by the camera. In a specific example, the camera module described herein is particularly well-suited for inclusion in a smart AI camera that is configured to perform dewarping on images captured by the camera.

Referring now to the drawings,FIG.1depicts a cross-sectional view of a lens barrel100that includes several lenses (including lens102) positioned in an interior of the lens barrel100, where optical axes of the lenses are aligned with one another, and further where a center axis (optical axis)104of the lens barrel100is coincident with the optical axes of the lenses (including an optical axis of the lens102). The lens barrel100has a first end106and a second end108that is opposite the first end106along a length of the lens barrel100.

The lens barrel100can include any suitable number of lenses. For instance, the lens barrel100may include between 1 and 20 lenses. In another example, the lens barrel100includes between 3 and 11 lenses. Pursuant to an example, the lens102(and other lenses in the lens barrel100) is composed of glass. In another example, the lens102(and other lenses in the lens barrel100) is composed of a transparent plastic. The lens barrel100has a circular cross section and is symmetric about the center axis104of the lens barrel100. It is to be understood, however, that the lens barrel100may have a cross section of a different shape (such as ovular, square, hexagonal, etc.), and the lens barrel100may be asymmetric.

The lens barrel100additionally includes a flange110located at the first end106of the lens barrel100. The flange110has a planar surface112that faces the second end108of the lens barrel100. The lens barrel100additionally includes a grip region114that extends from the flange110away from the first end106of the lens barrel100and towards the second end108of the lens barrel100. The diameter of the lens barrel100may taper in steps from the flange110of the lens barrel100towards the second end108of the lens barrel100. Therefore, the diameter of the lens barrel100in the grip region114may be greater than a diameter of the lens barrel100at the second end108of the lens barrel100.

The lens barrel100further includes a threaded region116that extends from the second end108of the lens barrel100towards the grip region114.

Turning now toFIGS.2-6, views of a camera module200that includes the lens barrel100are depicted.FIGS.2and3are isometric views of the camera module200FIG.4is a side view of the camera module200,FIG.5is a partially exploded view of the camera module200, andFIG.6is a cutaway view of the camera module200. The camera module200includes the lens barrel100, a lens holder202, and an image sensor board204, where the lens barrel100is coupled to the lens holder202, and the image sensor board204is coupled to the lens holder202, where the image sensor board204has an image sensor206therein. The lens holder202is coupled to the lens barrel100at the second end108of the lens barrel100. For example, the lens holder202includes a threaded recessed region that is configured to receive the threaded region116of the lens barrel100, Hence, the lens barrel100is screwed into the lens holder202. In other examples, the lens barrel100is coupled to the lens holder202by way of fasteners, such as threaded fasteners, rivets, etc.

The lens holder202has a base208that includes pins210and212that extend from the base208of the lens holder202towards the flange110of the lens barrel100when the lens barrel100is screwed into the lens holder202.

The lens barrel100, the lens holder202, and the image sensor board.204are aligned with one another during an active alignment process, such that when alignment is complete, the center axis104of the lens barrel100intersects a center of the image sensor206of the image sensor board204(as depicted inFIG.5), and the image sensor206is approximately orthogonal to the center axis104of the lens barrel100. With more particularity, the lens barrel100is coupled (e.g., screwed into) the lens holder202, and the lens barrel100(with the lens holder202coupled thereto) is positioned relative to a target in a scene such that the center axis104points to the target. The lens barrel100(and the lens holder202) is then held at such position. The image sensor board204is subsequently positioned relative to the lens holder202such that the center axis104of the lens barrel100intersects the image sensor206at a center of the image sensor206, and the image sensor206is approximately orthogonal to the center axis104of the lens barrel100. Upon the image sensor board204being properly aligned with the lens barrel100, ultraviolet (UV) adhesive is applied to interfaces between the image sensor board204and the lens holder202(as depicted inFIG.6) and between the lens barrel100and the lens holder202. Relative positions of the lens barrel100, lens holder202, and the image sensor board204are fixed upon the adhesive curing; however, external forces (such as a moment force between the image sensor board204and the lens holder202caused by weight of the lens barrel100and the lens holder202) may weaken the adhesive joints, causing undesired movement of the lens barrel100relative to the image sensor206. The technologies described below are well suited to constrain such undesired movement. A center of gravity of the camera module200is approximately coincident with the optical axis104of the lens barrel100and within the grip region114of the lens barrel100.

FIGS.7-14depict an assembly700that includes the camera module200, a retaining mechanism701, and a barrel retainer710, where kinematic mounting techniques are employed to constrain movement of the lens barrel100relative to the image sensor board204, and to mitigate forces that are applicable at the adhesive joints referenced above. The retaining mechanism701is configured to restrict movement of the lens barrel100. In the examples shown inFIGS.7-14, the retaining mechanism701is a bracket. In another example that will be discussed below, the retaining mechanism701is a monolithic base that is configured to retain multiple lens barrels that are pointed in different directions.

As depicted inFIGS.8,10,11,12, and13, the retaining mechanism701holds the lens barrel100at the grip region114of the lens barrel100to restrict movement of the lens barrel100, the lens holder202, and the image sensor board204relative to the retaining mechanism701. As illustrated inFIG.13, the retaining mechanism701can include a V-block, where the exterior of the lens barrel100at the grip region114is in contact with two of the planar surfaces of the V-block. In another embodiment, the retaining mechanism701may include a concave section that corresponds to the convex exterior of the lens barrel100at the grip region114.

As depicted inFIG.11, the retaining mechanism701further includes a planar surface702that, when the lens barrel100is held by the retaining mechanism701at the grip region114, abuts the planar surface112of the flange110of the lens barrel100to constrain translation of the lens barrel100relative to the retaining mechanism701(e.g., constrain translation in Z). As illustrated inFIG.12, the retaining mechanism701further has an extension706that extends away from the first end106of the lens barrel100and towards the base208of the lens holder202(and towards the second end108of the lens barrel100). The extension706includes a slot708, where the slot708is configured to accept the first pin210of the lens holder202. Engagement of the first pin210and the slot708constrains rotation of the lens barrel100(and thus the lens holder202and the image sensor board204) about the optical axis104of the lens barrel100relative to the restraining mechanism701(e.g., constrains rotation about Z).

The assembly700additionally includes a barrel retainer710that is attached to the retaining mechanism701by way of fasteners711. For instance, as illustrated inFIG.12, the barrel retainer710includes apertures and threaded fasteners are passed through the apertures. The retaining mechanism701can include correspondingly threaded recesses for receiving the fasteners711. Thus, a compressive force is formed between the barrel retainer710and the retaining mechanism701as the barrel retainer710is fastened to the retaining mechanism701.

As illustrated in the cross-sectional view through section A-A inFIG.13, the barrel retainer710has a concave surface that corresponds to the convex exterior of the grip region114of the lens barrel100. A gasket712is adhered to the concave surface of the barrel retainer710and is in contact with the convex exterior surface of the grip region114of the lens barrel100. The fasteners711facilitate provision of a compressive force onto the lens barrel100, thereby restricting translation of the lens barrel100(and the lens holder202and the image sensor board204) in X, Y, and Z directions in the assembly700, and further preventing the camera module200from tipping and/or tilting in the assembly700.

As is viewable inFIG.12, the barrel retainer710extends from the planar surface112of the flange110to the planar surface of the base208of the lens holder202. The barrel retainer710has an extension714that includes an aperture716that is configured to receive the second pin212of the lens holder202. Engagement between the second pin212and the aperture716of the extension714further constrains rotation of the combination of the camera module200in Z relative to the retaining mechanism701and the barrel retainer710. The cross-sectional view across section B-B shown inFIG.14depicts the pins210and212engaged with the slots708and the aperture716, respectively, thereby constraining rotation of the camera module200within the assembly700about the optical axis104of the lens barrel100.

As shown inFIG.13, the retaining mechanism701may include apertures718by way of which fasteners can pass through and fasten the retaining mechanism701(and therefore fasten the assembly700) to a mounting surface of a camera enclosure. Rubber isolation grommets can be placed between the retaining mechanism701and camera enclosure at the mounting apertures718to reduce the transmission of impact transmitted into the camera module200if the camera is jostled or dropped.

FIG.15depicts an example camera1500that may include the assembly700.

FIG.16depicts use of a fixture1600in connection with mounting the camera assembly700to an enclosure of a camera. The first end106of the lens barrel100is fit into an aperture1602of the fixture1600. The fixture1600conformally fits into the enclosure, thereby securing the assembly700in X and Y directions relative to the camera enclosure. Fasteners (that extend through the apertures718of the assembly700) secure the assembly700in the Z direction relative to the assembly700, In another example embodiment, the fixture1600is optional, as securing the assembly700to the enclosure without the fixture1600allows for refined positioning in X and Y directions within the enclosure.

Advantages of the technologies described herein are now set forth. It is noted that the camera module200is held by the retaining mechanism701at the gripping region114of the lens barrel100, the lens barrel100is fixed to the lens holder202with UV adhesive, and further the lens holder202is fixed to the image sensor board204with UV adhesive. The combination of the retaining mechanism701and the barrel retainer710constrains translation and rotation of the lens barrel100(and the lens holder202and image sensor board204), thus facilitating maintenance of alignment between the lens barrel100and the image sensor206. As the camera module200is held near its center of gravity by the retaining mechanism701and the barrel retainer710, moment force at the adhesive joints is reduced when compared to conventional approaches. Therefore, if the camera1500is jostled or dropped, the lens barrel100, the lens holder202, and the image sensor board204do not move relative to one another, and thus the alignment between the lens barrel100and the image sensor206is maintained.

FIG.17is an overhead view of the camera1500, andFIG.18is a cross-sectional view of the camera1500, where such figures are set forth to illustrate use of rubber isolation grommets that are configured to reduce transmission of impact into the camera module500if the camera1500is jostled or dropped. As shown, fasteners1702extended through the mounting apertures718and couple the assembly700to the camera1500at a mounting surface1802in the camera1500. Rubber isolation grommets1704are placed between the retaining mechanism701and camera enclosure at the mounting apertures718to reduce the transmission of impact transmitted into the camera module if the camera1500is jostled or dropped.

FIG.19illustrates another embodiment of the retaining mechanism701. In the example shown inFIG.19, the retaining mechanism701is a monolithic base1900that includes numerous V-blocks1902-1908that are configured to receive several respective camera modules. In the base1900depicted inFIG.19, axes of lens barrels are directionally offset from one another by 90 degrees. The base1900is particularly well suited for applications when a camera system that includes the base1900is configured to generate 360-degree panoramic images (e.g., where images generated from four different cameras are stitched together). Utilization of the V-blocks1902-1908in the base1900ensures that the optical axis of lenses in the camera modules that are in contact with the V-blocks1902-1908lie in the same plane, such that images generated through use of the camera modules can be readily stitched to one another. While the base1900is illustrated as including four V-blocks, it is to be understood that the base1900may include fewer or more than four V-blocks.

FIG.20illustrates an exemplary methodology2000for mounting a camera module to a mounting surface of a camera enclosure. While the methodology is shown and described as being a series of acts that are performed in a sequence, it is to be understood and appreciated that the methodology is not limited by the order of acts in the sequence. For example, some acts can occur in a different order than what is described herein. In addition, an act can occur concurrently with another act. Further, in some instances, not all acts may be required to implement a methodology described herein.

The methodology2000starts at2002, and at2004active alignment is performed between an optical axis of lenses of a lens barrel and an image sensor mounted on an image sensor board, as described above. More specifically, the lens barrel is formed such that lenses therein have optical axes that are coincident with one another and are also coincident with a center axis of the lens barrel. The lens barrel is coupled to a lens holder (e.g., screwed into the lens holder) at a first end of the lens barrel, and an image sensor of an image sensor board is positioned adjacent to the image sensor board. The lens barrel is held at a fixed position, with the center axis of the lens barrel (and thus the axes of the lenses therein) pointed to a target; position of the lens holder and the image sensor are adjusted until appropriate alignment is achieved between the center axis of the lens barrel and the image sensor, whereupon the positions of the lens barrel, the lens holder, and the image sensor board are fixed relative to one another by applying adhesive at interfaces between such elements, thereby forming a camera module.

At2006, the camera module is placed into a retaining mechanism, where the retaining mechanism comprises a V-block and a planar surface. The camera module is placed in the retaining mechanism such that a grip region of the lens barrel is in contact with surfaces of the V-block, and the planar surface of the retaining mechanism is in contact with (abutted to) a planar surface of a flange of the lens barrel. The flange is located at the second end of the lens barrel. An extension of the retaining mechanism engages with a pin of the lens holder to constrain rotation of the lens barrel about the optical axis of the lens relative to the retaining mechanism.

At2008, a lens retainer is fastened to the retaining mechanism (to provide a compressive force on the lens barrel), where the lens retainer has a gasket adhered thereto, and further where the gasket is in contact with the grip region of the lens barrel when the lens retainer is fastened to the retaining mechanism. Coupling between the lens barrel and the surfaces of the V-block and the lens barrel and the gasket prevents translation of the camera module in directions that are orthogonal to the optical axis of the lens barrel (prevents rotation in X, Y, and Z).

At2010, the retaining mechanism is coupled to a mounting surface of a camera enclosure. For instance, the retaining mechanism is coupled to a chassis in the camera enclosure, thereby fixing the position of the camera module in the camera enclosure. The methodology2000completes at2012.

The features described herein relate to a camera assembly that is well-suited for use in a smart camera that performs dewarping, according to at least the examples provided below.

(A1) In one aspect, some embodiments include an assembly for including in a camera, where the assembly includes a camera module. The camera module includes a lens barrel having a first end and a second end that is opposite the first end, where the lens barrel includes: a) a lens positioned in an interior of the lens barrel, the lens having an optical axis; h) a flange at the first end of the lens barrel, the flange having a planar surface that faces the second end of the lens barrel; and c) a grip region that extends from the flange towards the second end of the lens barrel. The camera module also includes a lens holder coupled to the lens barrel at the second end of the lens barrel, the lens holder including a pin that extends from the lens holder towards the first end of the lens barrel. The camera assembly also includes a retaining mechanism, where the retaining mechanism is configured to hold the camera module at the grip region of the lens barrel to constrain translation of the camera module relative to the retaining mechanism in a plane that is orthogonal to the optical axis. The retaining mechanism has a planar surface that abuts the planar surface of the flange of the lens barrel to constrain translation of the camera module relative to the retaining mechanism along the optical axis of the lens. Additionally, the retaining mechanism has an extension that extends towards the lens holder and engages with the pin, where engagement of the extension with the pin constrains rotation of the camera module relative to the retaining mechanism about the optical axis of the lens.

(A2) in some embodiments of the camera assembly of A1, the retaining mechanism is a bracket.

(A3) In some embodiments of the camera assembly of any of A1-A2, the retaining mechanism includes a V-block that comprises a first planar surface and a second planar surface, where the lens barrel of the camera module is in contact with the first planar surface and the second planar surface of the V-block.

(A4) In some embodiments of the camera assembly of any of any of A1 or 43, the retaining mechanism is a monolithic base that holds several lens barrels.

(A5) in some embodiments of the camera assembly of any of AI-A4, a center of gravity of the camera module is within the grip region of the lens barrel.

(A6) In some embodiments of the camera assembly of any of A1-A5, the lens barrel has a circular cross section, where the lens barrel has a first diameter at the first end of the lens barrel and a second diameter at the second end of the lens barrel, the first diameter larger than the second diameter.

(A7) In some embodiments of the camera assembly of any of A1-A6, the camera assembly additionally includes a barrel retainer that is attached to the retaining mechanism by fasteners and a gasket that is adhered to the barrel retainer, where the gasket is in contact with the grip region of the lens barrel.

(A8) In some embodiments of the camera assembly of A7, the lens holder has a second pin extending therefrom, the barrel retainer includes an aperture, and the second pin is located in the aperture of the barrel retainer to further constrain rotation of the camera module relative to the retaining mechanism about the optical axis of the lens.

(A9) In some embodiments of the camera assembly of any of A1-A8, the lens is formed of glass.

(A10) In some embodiments of the camera assembly of any of A1-A9, the lens barrel comprises between three and eleven lenses.

(B1) In another aspect, some embodiments include a method for mounting an assembly to a mounting surface of a camera enclosure. The method includes forming a camera module, wherein forming the camera module includes coupling a first end of a lens barrel to a lens holder, where the lens barrel includes a lens that has an optical axis. The method further includes forming the assembly, where forming the assembly includes placing the camera module into a retaining mechanism, where the retaining mechanism comprises a V-block and a planar surface. The camera module is placed in the retaining mechanism such that a grip region of the lens barrel is in contact with surfaces of the V-block and the planar surface is in contact with a planar flange of the lens barrel. The planar flange is located at the second end of the lens barrel, and an extension of the retaining mechanism engages with a pin of the lens holder to constrain rotation of the camera module relative to the retaining mechanism about the optical axis of the lens. Forming the assembly also includes fastening a lens retainer to the retaining mechanism, where the lens retainer has a gasket, and the gasket is in contact with the grip region of the lens barrel when the lens retainer is fastened to the retaining mechanism. Coupling between the camera module and the surfaces of the V-block and the camera module and the gasket constrains translation of the camera module relative to the retaining mechanism in directions orthogonal to the optical axis. The method also includes mounting the assembly to the mounting surface of the camera enclosure subsequent to forming the assembly.

(B2) In some embodiments of the method of B1, forming the assembly additionally engaging an extension of the retaining mechanism with a second pin of the lens holder to constrain rotation of the camera module relative to the retaining mechanism about the optical axis of the lens.

(B3) In some embodiments of any of the methods of B1-B2, the retaining mechanism is a bracket, and the bracket has an aperture that extends therethrough, where mounting the assembly to the mounting surface of the camera enclosure further includes attaching the bracket to the camera enclosure by way of a fastener that extends through the aperture of the bracket.

(B4) In some embodiments of any of the methods of B1-B3, the lens barrel has a circular cross section.

(B5) In some embodiments of any of the methods of B1-B4, the first end of the lens barrel is threadedly coupled to the lens holder.

(B6) In some embodiments of any of the methods of B1-B5, a center of gravity of the camera module is within the grip region of the lens barrel.

(B7) In some embodiments of any of the methods of B1-B6, a rubber isolation grommet is placed between the retaining mechanism and the camera enclosure to reduce transmission of impact into the camera module when a camera that comprises the camera module is jostled or dropped.

(B8) In some embodiments of any of the methods of B1-B7, forming the assembly also includes placing multiple camera modules in the retaining mechanism.

(B9) In some embodiments of the method of B8, the multiple camera modules comprise four camera modules that have optical axes that are offset from one another by 90 degrees.

(C1) In another aspect, some embodiments include a camera assembly. The camera assembly includes a camera module, where the camera module includes a lens barrel. The lens barrel includes: a) a lens positioned in an interior of the lens barrel, the lens having an optical axis; b) a flange at a first end of the lens barrel, the flange having a planar surface that faces a second end of the lens barrel that is opposite the first end; and c) a grip region that extends from the flange towards the second end of the lens barrel. The camera module also includes a lens holder coupled to the second end of the lens barrel; where the lens holder includes a pin that extends from the lens holder towards the first end of the lens barrel. The camera also includes retaining means for restricting movement of the camera module relative to the retaining means.

What has been described above includes examples of one or more embodiments. It is, of course, not possible to describe every conceivable modification and alteration of the above devices or methodologies for purposes of describing the aforementioned aspects, but one of ordinary skill in the art can recognize that many further modifications and permutations of various aspects are possible. Accordingly, the described aspects are intended to embrace all such alterations, modifications, and variations that fall within the spirit and scope of the appended claims. Furthermore; to the extent that the term “includes” is used in either the detailed description or the claims, such term is intended to be inclusive in a manner similar to the term “comprising” as “comprising” is interpreted when employed as a transitional word in a claim.