GB2593682A

GB2593682A - A Camera Assembly

Info

Publication number: GB2593682A
Application number: GB2004519.1A
Authority: GB
Inventors: Carr Joshua
Original assignee: Cambridge Mechatronics Ltd
Current assignee: Cambridge Mechatronics Ltd
Priority date: 2020-03-27
Filing date: 2020-03-27
Publication date: 2021-10-06
Anticipated expiration: 2040-03-27
Also published as: CN216118171U; GB202004519D0; GB2593682B

Abstract

A camera assembly 1 has an image sensor 4 mounted on its body 13 and a lens carriage 5 with a proximal end and a distal end further from the image sensor. An actuator assembly 7 with conductive components (8, figure 1) at or towards the distal end drives movement of the lens carriage. Another camera assembly has a shape memory alloy (SMA) actuator to effect movement of the lens carriage orthogonal to the optical axis and an auxiliary actuator to move the lens carriage along the optical axis where part of the SMA actuator is further from the image sensor than the auxiliary actuator. Another camera assembly has a body with a second portion 11 connected to a lens carriage and an actuator assembly which partly encloses an image sensor in a first portion. A further camera assembly has a SMA actuator assembly and SMA components which effect movement of the lens carriage in at least one direction orthogonal to the optical axis, spaced from the image sensor by 300 or >400 micrometres. A further camera assembly includes a lens carriage and an image sensor on a base 4 partly enclosed by a shielding can 11.

Description

A CAMERA ASSEMBLY

The present invention generally relates to a camera assembly and a method of manufacturing the camera assembly.

Background

Actuators are used in camera assemblies for effecting a range of motions of a lens carriage, in order to provide various functions such as zoom, autofocus (AF) and optical image stabilization (OIS).

As an example, W02011/104518A discloses a shape memory alloy (SMA) actuator for controlling a lens carriage in a smartphone camera with the use of eight lengths of SMA wire. Upon energising, the lengths of SMA wire are selectively contracted to move the lens carriage, thus providing zoom, AF and OIS capabilities.

Alternatively, AF and OIS functions may be provided by discrete actuators each responsible for one of the functions. For example, W02016/009200 discloses the use of a voice coil motor (VCM) for moving the lens carriage along an optical axis to perform AF, in addition to an SMA actuator configured to shift the lens carriage orthogonally to the optical axis so as to provide OIS. In this example, the VCM is stacked on the SMA actuator and together the two are supported on a support structure that includes an image sensor.

Summary

To achieve better control characteristics, SMA actuators are may be driven by pulse width modulation (PWM) drive signals. Typically, when PWM is used to deliver power, the PWM frequency may be fixed, and power may be sequentially applied to each SMA wire during each PWM cycle/period. However, the use of a PWM drive signal may cause electromagnetic interference at the image sensor of the camera, which in turn may lead to undesirable artefacts to appear in the captured image. Such a problem may be particularly pronounced in miniature cameras because, in order to simplify the electrical connections, their actuators are typically fixed onto the support structures and in the immediate vicinity of the image sensor. This problem may be resolved by providing a screening shield positioned in between the actuator and the image sensor. However, the addition of a screening shield tends to increases the overall height of the camera assembly. This may be problematic for applications such as smartphones where the thickness of the device is critical. Additionally, the use of a screening shield requires additional manufacturing steps, as well as the cost of the camera assembly.

The present invention provides camera assemblies that may achieve a reduction in electromagnetic interference in the vicinity of the image sensor, optionally without the use of a screening shield, or at least reduce the significance of a screening shield. Advantageously, such an arrangement may allow the height of the camera assembly to be reduced or maintained, as well as reducing the bill of material (BOM) and manufacturing steps associated with including a screening shield.

According to a first aspect of the present invention, there is provided camera assembly comprising: a body having an image sensor mounted thereon; a lens carriage comprising a lens having an optical axis, the lens carriage having a proximal end, and a distal end positioned further from the image sensor along the optical axis than the proximal end; and an actuator assembly comprising a set of conductive components configured to drive movement of the lens carriage relative to the image sensor, wherein the set of conductive components are positioned at or towards the distal end of the lens carriage.

The actuator assembly may be a micro-actuator for a camera or a mobile phone, wherein the set of conductive components may be conductive components in the actuator assembly that cause electromagnetic interference at the image sensor when driven by PWM drive signals. In some embodiments, the actuator assembly may comprise a voice coil motor (VCM) where the set of conductive components may be wire coils in the VCM. The VCM may configured to provide zoom and autofocus (AF) in the lens carriage.

Preferably, the actuator assembly comprises an shape memory alloy (SMA) actuator, the SMA actuator comprises one or more (e.g. elongate) SMA components corresponding to the set of conductive components. The SMA components may connect the body and the lens carriage, and the or each SMA component may be configured to, on contraction, effect movement of the lens carriage in at least one direction substantially orthogonal to the optical axis. Such arrangement may enable at least one of zoom, autofocus (AF) and optical image stabilisation (OIS) to be performed upon actuating some or all of the SMA component. Preferably, the or each SMA component is configured to, on contraction, effect movement in the lens carriage at least one axis orthogonal to the optical axis. For example, the one or more SMA components may extend in a direction substantially orthogonal to the optical axis. Such an arrangement may enable the camera assembly with optical image stabilisation (OIS) or autofocus (AF) capabilities. The SMA components may extend in different directions and in close proximity to each other. Each of the SMAs component may preferably be an SMA wire, or it may be a strip, or a rod formed from SMA materials. In some embodiments, for example ones that employ eight components, the contraction of SMA components may cause the lens carriage to move relative to the image sensor with six degrees of freedom.

The SMA wires may form from any suitable shape memory alloy material, typically a nickel-titanium alloy (e.g. Nitinol), but they may also contain tertiary components such as copper. The SMA wires may have any cross-sectional profile and diameter suitable for the application. For example, the SMA wires may have a cross section diameter of 251.trn capable of generating a maximum force of between 120mN to 200mN whilst maintaining the strain in the SMA wire within safe limits (e.g. 2-3% reduction in length over original length). Increasing the diameter of each SMA wire from 25pm to 35Rm approximately doubles the cross-sectional area of the SMA wire and thus approximately doubles the force provided by each SMA wire.

The lens carriage may be of any suitable shape and size. When the set of conductive components are positioned towards the distal end of the lens carriage, the electromagnetic inference at the image sensor, e.g. at a location adjacent to the proximal end of the lens carriage, may be significantly reduced. In some examples, most of the set of conductive components are positioned in the half of the lens carriage that is closest to the distal end. In some examples, all of the set of conductive components are positioned in the half of the lens carriage that is closest to the distal end. In some examples, all of the set of conductive components are positioned in the quarter of the lens carriage that is closest to the distal end. Such arrangement differs to conventional camera assembly, thus the electrical connection between the actuator assembly and the electrical terminals at the body may need to be modified accordingly to accommodate the change in actuator position.

Advantageously, such arrangement may reduce the amount of electromagnetic interference at the image sensor, thereby it may help suppressing undesirable artefacts that may appear in the captured image, optionally without the use of a screening shield.

Optionally, the actuator assembly comprises an auxiliary actuator configured to, upon actuation, effect movement of the lens carriage along the optical axis. The auxiliary actuator may a voice coil motor (VCM), or it may be an auxiliary SMA actuator. The auxiliary SMA actuator may have a different wiring arrangement to the SMA actuator for performing zoom and autofocus (AF). The auxiliary SMA actuator may comprise a return spring in lieu of some of the SMA components.

Optionally, the SMA actuator and the auxiliary actuator are stacked along the optical axis. That is, in a side view the auxiliary actuator may, at least in part, lie over the SMA actuator.

Optionally, at least part of the SMA actuator is positioned further from the image sensor along the optical axis than the auxiliary actuator.

Preferably, at least the actuator in the actuator assembly is configured to be driven by a pulse width modulation (PWM) drive signal. Advantageously, the use of PWM drive signal may lead to more actuate positioning of the lens carriage, as well as power distribution amongst the SMA wires.

However, the use of PWM drive signal may be the source of electromagnetic 35 interference. Therefore, in some embodiment, the SMA actuator may be positioned closer to the distal end of the lens carriage than the auxiliary actuator. By positioned at a distance farthest away from the image sensor, such arrangement may advantageously limit the electromagnetic inference at the image sensor.

Optionally, the camera assembly further comprises a base on which the image sensor is mounted; and a shielding can extending from base so as to at least partly enclosing the image sensor, the lens carriage and the actuator assembly, wherein the actuator assembly is connected to the base via the shielding can. The shielding can may be a magnetic shield in a form of a receptable for partially or fully enclosing the image sensor, lens carriage and the actuator assembly, so as to provide magnetic shielding from external magnetic and electromagnetic interference, e.g. from other components of the smartphone device. The shielding can may structurally support the actuator assembly on the base. That is, in such arrangement, the actuator assembly may extend from an internal wall of the shielding can, and may not directly contact the base. The actuator assembly may be electrically and/or mechanically connected to the base via the shielding can Optionally, the shielding can is a modular unit attachable to the base to form the body of the camera assembly. For example, the actuator assembly may be first assembled to the shielding can. The assembled shielding can may then attach onto the base to from the body. This may advantageously allow the relative position of the lens carriage and the image sensor to be fine-tuned or adjusted by traversing the assembled shielding can over the base. In some embodiments the shielding can may be attached to the base by welding or other permanent fixings. In some other embodiments, the shielding can may be attached to the base by detachable fixtures, such that the actuator assembly is detachable from the base during servicing and/or cleaning.

Preferably, the shielding can may comprise conductive paths provided along at least one side wall, wherein the conductive paths may electrically connect the set of conductive components with electrical terminals at the base. The conductive paths may be etched conductor or flexible printed circuit (FPC) overlaid on the shielding can, or it may be a metallic part of the shielding can. Advantageously, by providing the conductive paths along the side wall, such arrangement may advantageously distance the conductive paths from the image sensor, as well as reducing the likelihood of loose wiring from getting in the way of any moveable components in the camera assembly.

Optionally, the shielding can comprises a flange with electrical terminals electrically connected to the actuator assembly and forming electrical connections with corresponding electrical terminals at the base. Alternatively, the shielding can comprises electrical terminals electrically connected to the actuator assembly and forming electrical connections with corresponding electrical terminals at the base.

Such arrangements may advantageously allow the electrical connections to form more precisely and efficiently during the assembly process.

Optionally, the lens carriage is generally tapered such that it is narrower at its distal end. Advantageously, having the OIS actuator positioned towards the distal 15 end may enable the camera assembly to have a smaller footprint, and/or enable a more powerful actuator to be used.

According to a second aspect of the present invention, there is provided a camera assembly comprising: a body having an image sensor mounted thereon; a lens carriage comprising a lens having an optical axis; a shape memory alloy (SMA) actuator comprising one or more SMA components connecting the body and the lens carriage, the or each SMA component being configured to, on contraction, effect movement of the lens carriage in at least one direction substantially orthogonal to the optical axis; and an auxiliary actuator configured to, upon actuation, effect movement of the lens carriage along the optical axis, wherein at least part of the SMA actuator is positioned further from the image sensor along the optical axis than the auxiliary actuator.

Optionally, the SMA actuator and the auxiliary actuator are stacked along the optical axis.

Optionally, the auxiliary actuator comprises an auxiliary SMA actuator or a voice coil motor.

Optionally, the camera assembly comprises circuitry configured to drive the SMA actuator with a pulse width modulation (PWM) drive signal.

According to a third aspect of the present invention, there is provided a camera assembly comprising: a body having a first portion on which an image sensor is mounted; a lens carriage comprising a lens having an optical axis; an actuator assembly configured to drive movement of the lens carriage relative to the image sensor in at least one direction relative to the optical axis, wherein the body comprises a second portion extending from the first portion so as to at least partly enclose the image sensor, the lens carriage and the actuator assembly, wherein the actuator assembly is connected to the second portion.

Optionally, the second portion is a modular unit configured to be attachable onto the first portion to form the body of the camera assembly.

Optionally, the second portion comprises conductive paths provided on at least one side wall, wherein the conductive paths electrically connect the actuator assembly and electrical terminals at the first portion.

Optionally, the first portion comprises a base and the second portion comprises a shielding can.

According to a fourth aspect of the present invention, there is provided a camera assembly comprising: a body having an image sensor mounted thereon; a lens carriage having an optical axis; and an actuator assembly comprising a shape memory alloy (SMA) actuator, wherein the SMA actuator comprises one or more SMA components connecting the body and the lens carriage, the or each SMA components being configured to, on contraction, effect movement of the lens carriage in at least one direction substantially orthogonal to the optical axis; and wherein the SMA components are spaced from the image sensor at a

S

distance of at least 300 micrometres, or at least 400 micrometres.

Advantageously, by placing the actuator at a distance of at least 300 micrometres, or at least 400 micrometres from the image sensor, the amount of electromagnetic interference at the image sensors may be reduced to a level that it no longer causes artefacts in the captured images.

According to a fifth aspect of the present invention, there is provided a method of manufacturing a camera assembly, comprising: assembling an actuator assembly into a shielding can, the actuator assembly being arranged to connect with a lens carriage; and attaching the assembled shielding can and actuator assembly onto a base such that the shielding can at least partly encloses the actuator assembly, the lens carriage and an image sensor provided on the base.

Optionally, the method further comprises inserting a lens into the lens carriage before, during, or after the attaching.

Optionally, the method further comprising connecting electrical terminals provided on the shielding can with corresponding terminals on the base, wherein the electrical terminals on the shielding can are electrically connected to the SMA components by respective conductive paths provided on at least one side wall of the shielding can.

Features of one aspect of the present invention may be combined with compatible features in other aspects of the present invention.

Brief Description of the Drawings

Certain embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows an exploded perspective view of a camera assembly according to an embodiment of the present invention; Figure 2 is a side sectional view of the camera assembly of Figure 1; and Figure 3 is a plot showing simulated peak magnetic field strength at various distance from the SMA actuator.

Detailed Description

Figures 1 and 2 respectively show an exploded perspective view and a side sectional view of a camera assembly 1 according to an embodiment of the present invention.

The camera assembly 1 comprises a sensor assembly 2 which comprises a flexible circuit board 3, an image sensor 4 mounted on the flexible circuit board, and a surround 13 which is a rigid structural element extending around the image sensor 4. The image sensor 4 is implemented in an integrated circuit chip. An infra-red filter 14 is fixed to the surround 13 and extends across the light-sensitive area of the image sensor 4.

The camera assembly 1 comprises a lens carriage 5 holding a lens 6 that has an optical axis 0 and is arranged to form an image on the image sensor 4. A single lens 6 is shown in Figure 1, but more than one lens 6 may be provided. The lens carriage is connected to a voice coil motor (VCM) 16 for moving the lens 6 in a direction along the optical axis 0 to provide autofocus (AF) functionality.

The camera assembly 1 comprises an SMA actuator 7 having plural SMA wires 8 connected between a static layer 9 (uppermost in Figure 1) and a movable layer (lowermost in Figure 1). In the example of Figure 1, four SMA wires 8 are provided, but in general any number of SMA wires 8 may be used.

The movable layer 10 can move relative to the static layer 9. In the example shown in Figure 1, the movable layer 10 moves laterally with respect to the optical axis 0, but in general the relative movement may be with any degree of freedom, for example translational movement along any axis and/or rotational movement about any axis.

In the illustrated example, the SMA actuator assembly 7 includes a suspension system, formed by flexures 12 connected between the static layer 9 and the movable layer 10, which supports the movable layer 10 in a manner allowing the desired movement of the movable layer 10 relative to the static layer 9. As an alternative, the suspension system could be formed in some other way, for example formed by ball bearings or a sliding bearing. As another alternative, the suspension system may be omitted in which case the movable layer 10 is supported on the static layer 9 solely by the SMA wires 8.

The static layer 9 is mounted to a ceiling 11a of a shielding can 11, and the movable layer 10 is connected to the VCM 16. More specifically, the SMA actuator 7 and the VCM 16 are arranged in a stack formation. Thus, the actuator assembly (SMA actuator and the VCM) and the lens carriage 5 can be said to be hanging from the ceiling 11a of the shielding can 11. As a result, the movement of the movable layer 10 relative the static layer 9 moves the lens carriage 5 in a direction orthogonal to the optical axis. Such an arrangement combines the optical image stabilisation (OIS) from the SMA actuator 7 with AF from the VCM 16. In some other examples, a sole SMA actuator having more than four SMA wires may be used. For example, the SMA actuator of W02011/104518A may be used for providing both AF and OIS capabilities. Thus, in such embodiments the VCM may be omitted.

Referring to Figure 2, the shielding can 11 is provided to enclose the actuator assembly and the image sensor 4. The primary functions of the shielding can 11 are to shield the enclosed components from foreign objects and dust ingress, as well as electromagnetic interference from other electronic components. In this embodiment, the shielding can 11 has a base 20 with electrical terminals 24 provided thereon. The electrical terminals 24 are arranged to connect with corresponding terminals 24 on the sensor assembly 2. In some other embodiments, the shielding can 11 and the base 20 may form from a single body.

In comparison to prior art embodiments where the actuator assembly is mounted directly onto a support structure having electrical terminals located thereon, the actuator assembly of the present invention comprises conductive paths 22 that route along the side wall of the shielding can 11. The conductive paths 22 may alternatively be provided along the external surface of the shielding can 11 to further reduce the impact of electromagnetic interference on the image sensor 4.

The shielding can 11 may be produced as a pre-assembled modular unit with the actuator assembly and lens carriage 5 installed therein. The pre-assembled modular unit may subsequently be built onto the sensor assembly 2 to form the camera assembly 1. The lens may be inserted into the lens carriage 5 of the pre-assembled modular unit prior to, during or after building onto the sensor assembly 2.

The use of such pre-assembled modular unit is advantageous in that it allows the relative position of the lens and the image sensor to be fine-tuned or adjusted to achieve optimal image alignment.

The camera assembly 1 includes a control circuit implemented in an integrated circuit chip attached to the sensor assembly 2. The control circuit is connected to the SMA wires 8 via the conductive paths 22 and supplies PWM drive signals thereto. The drive signals are carried by conductive components of the SMA actuator assembly 7 including the SMA wires 8 themselves and other conductive components electrically connected to the SMA wires 8. The drive signals provide resistive heating of the SMA wires 8 to selectively vary their temperature, and hence the degree of their contraction. Heating is provided directly by the drive signals. Cooling is provided by reducing the power of the drive signal to allow the SMA wires 8 to cool by conduction, convection and radiation to their surroundings.

The PWM drive signals are pulsed signals that are switched on and off to modulate the power of the drive signal. They may be derived from any type of current source, for example a constant current source or a constant voltage source and may in general be any type of switched signal. The duty cycle of the PWM drive signals is altered to modulate the power of the drive signal. The PWM drive signal may have a constant period, in which case the duty cycle is varied by changing the time that the drive signal is switched on. When the PWM drive signal is pulsed through the SMA wires 8 and other conductive components, this current causes an electro-magnetic field to be formed. The pulsed fields interfere with the image sensor 4 and the tracks connected thereto, causing noise which, in some cases, could potentially cause artefacts to form on the displayed image.

Thus, by moving the actuator assembly towards a distal end of the lens carriage 5, e.g. a position adjacent to the ceiling of the shielding can 11, the electromagnetic inference at the image sensor 4 may be significantly reduced. This advantageously reduces or eliminates the appearance of artefacts on an image as captured by the image sensor 4. Such arrangement may enable the SMA actuator 7 to be spaced from the image sensor 4 by a distance of at least 300 micrometres. Ideally, the SMA actuator 7 may be spaced from the image sensor by a distance of at least 400 micrometres because, as shown in a simulated peak magnetic field strength plot of Figure 3, the magnetic field strength at a distance of 400pm from the SMA actuator is comparable to Earth's field strength. Thus, at such distance, the electromagnetic interference at the image sensor can be negligible.

In some embodiments, the lens carriage is generally tapered such that it is narrower at its distal end. Advantageously, having the OIS actuator positioned towards the distal end may enable the camera assembly to have a smaller footprint, and/or enable a more powerful actuator to be used. For example, the size of the OIS actuator may, to a degree, less restricted by design constraints.

Claims

CLAIMS1. A camera assembly comprising: a body having an image sensor mounted thereon; a lens carriage comprising a lens having an optical axis, the lens carriage having a proximal end, and a distal end positioned further from the image sensor along the optical axis than the proximal end; and an actuator assembly comprising a set of conductive components configured to drive movement of the lens carriage relative to the image sensor, wherein the set of conductive components are positioned at or towards the distal end of the lens carriage.
2. A camera assembly according to claim 1, wherein the actuator assembly comprises a shape memory alloy (SMA) actuator comprising one or more SMA components corresponding to the set of conductive components, wherein the SMA components connect the body and the lens carriage, and the or each SMA component is configured to, on contraction, effect movement of the lens carriage in at least one direction substantially orthogonal to the optical axis.
3. A camera assembly according to claim 1 or 2, wherein the actuator assembly comprises an auxiliary actuator configured to, upon actuation, effect movement of the lens carriage along the optical axis.
4. A camera assembly according to claim 3, wherein the auxiliary actuator 25 comprises an SMA actuator or a voice coil motor (VCM).
5. A camera assembly according to claim 3 or 4, when dependent on claim 2, wherein the SMA actuator and the auxiliary actuator are stacked along the optical axis.
6. A camera assembly according to any one of the claims 3 to 5, when dependent on claim 2, wherein at least part of the SMA actuator is positioned further from the image sensor along the optical axis than the auxiliary actuator.
7. A camera assembly according any one of the preceding claims, wherein the body comprises: a base on which the image sensor is mounted; and a shielding can extending from the base so as to at least partly enclosing the image sensor, the lens carriage and the actuator assembly, wherein the actuator assembly is connected to the base via the shielding can.
8. A camera assembly according to any one of the claims 7, wherein the shielding can is a modular unit attachable to the base to form the body of the camera assembly.
9. A camera assembly according to claim 7 or 8, wherein the shielding can comprises: a flange with electrical terminals electrically connected to the actuator assembly and forming electrical connections with corresponding electrical terminals at the base.
10. A camera assembly according to any one of the claims 7 to 9, wherein the shielding can comprises conductive paths provided on at least one side wall, wherein the conductive paths electrically connect the set of conductive components with electrical terminals at the base.
11. A camera assembly according any one of the preceding claims, comprising circuitry configured to drive the set of conductive components with a pulse width modulation (PWM) drive signal.
12. A camera assembly comprising: a body having an image sensor mounted thereon; a lens carriage comprising a lens having an optical axis; a shape memory alloy (SMA) actuator comprising one or more SMA 30 components connecting the body and the lens carriage, the or each SMA component being configured to, on contraction, effect movement of the lens carriage in at least one direction substantially orthogonal to the optical axis; and an auxiliary actuator configured to, upon actuation, effect movement of the lens carriage along the optical axis, wherein at least part of the SMA actuator is positioned further from the image sensor along the optical axis than the auxiliary actuator.
13. A camera assembly according to claim 12, wherein the SMA actuator and the auxiliary actuator are stacked along the optical axis.
14. A camera assembly according to claim 12 or 13, wherein the auxiliary actuator comprises an auxiliary SMA actuator or a voice coil motor.
15. A camera assembly according any one of the claims 12 to 14, comprising circuitry configured to drive the SMA actuator with a pulse width modulation (PWM) drive signal.
16. A camera assembly according to any one of the preceding claims, wherein the lens carriage is generally tapered such that it is narrower at its distal end. 15
17. A camera assembly comprising: a body having a first portion on which an image sensor is mounted; a lens carriage comprising a lens having an optical axis; an actuator assembly configured to drive movement of the lens carriage relative to the image sensor in at least one direction relative to the optical axis, wherein the body comprises a second portion extending from the first portion so as to at least partly enclose the image sensor, the lens carriage and the actuator assembly, wherein the actuator assembly is connected to the second portion.
18. A camera assembly according to claim 17, wherein the second portion is a modular unit configured to be attachable onto the first portion to form the body of the camera assembly.
19. A camera assembly according to any one of the claims 17 or 18, wherein the second portion comprises conductive paths provided on at least one side wall, wherein the conductive paths electrically connect the actuator assembly and electrical terminals at the first portion.
20. A camera assembly according to any one of the claims 17 to 19, wherein the first portion comprises a base and the second portion comprises a shielding can.
21. A camera assembly comprising: a body having an image sensor mounted thereon; a lens carriage having an optical axis; and an actuator assembly comprising a shape memory alloy (SMA) actuator, wherein the SMA actuator comprises one or more SMA components connecting the body and the lens carriage, the or each SMA components being configured to, on contraction, effect movement of the lens carriage in at least one direction substantially orthogonal to the optical axis; and wherein the SMA components are spaced from the image sensor at a distance of at least 300 micrometres, or at least 400 micrometres.
22. A method of manufacturing a camera assembly, comprising: assembling an actuator assembly into a shielding can, the actuator assembly being arranged to connect with a lens carriage; and attaching the assembled shielding can and actuator assembly onto a base such that the shielding can at least partly encloses the actuator assembly, the lens carriage and an image sensor provided on the base.
23. A method according to claim 22, further comprises inserting a lens into the lens carriage before, during, or after the attaching.
24. A method according to claim 22 or 23, further comprising connecting electrical terminals provided on the shielding can with corresponding terminals on the base, wherein the electrical terminals on the shielding can are electrically connected to the SMA components by respective conductive paths provided on at least one side wall of the shielding can.