TECHNICAL FIELD

The disclosure relates to an optical arrangement for an electronic apparatus, the optical arrangement comprising a first optics group and a second optics group together defining an optical axis. An actuating unit is configured to generate movement of at least the first optics group from a retracted position to an extended position along the optical axis.

BACKGROUND

Telescopic camera optics using retracting and protruding lens systems to achieve longer focal length cameras having, e.g., zoom or telephoto functions, have existed for many years in the digital still camera industry. These solutions, however, require higher level miniaturization and robustness to be able to be used in smaller apparatuses such as smartphones.

Nevertheless, the resulting apparatus is still thick and bulky. It may not have the required durability against mechanical impact that is expected from a product used in daily life such as a phone. It also may require strengthening of the phone frame or housing to be able to withstand the forces created by the protruding optics, for example, to protect the display unit or the battery from damage. Furthermore, existing solutions either accept that some undesirable clearances exist within the optical arrangement, or they comprise additional components designed to remove those clearances.

Hence, there is a need for an improved optical arrangement for electronic apparatuses such as smartphones.

SUMMARY

It is an object to provide an improved optical arrangement. The foregoing and other objects are achieved by the features of the independent claims. Further implementation forms are apparent from the dependent claims, the description, and the figures.

According to a first aspect, there is provided an optical arrangement for an electronic apparatus, the optical arrangement comprising a first optics group and a second optics group together defining an optical axis, an actuating unit configured to generate movement of at least the first optics group from a retracted position to an extended position along the optical axis, the actuating unit comprising an actuator configured to rotate around the optical axis in a first direction, a first retaining element configured to translate along the optical axis and to rotate around the optical axis in response to the rotation of the actuator, a second retaining element configured to rotate, in response to the rotation of the first retaining element, from an engaged position, wherein the second retaining element engages and maintains the first optics group in the retracted position, to a disengaged position, wherein the first optics group is released, allowing movement of the first optics group from the retracted position to the extended position, and a resilient element being in a first compression state when the first retaining element in a first linear position along the optical axis and in a second compression state when the first retaining element is in a second linear position along the optical axis. A base is configured to accommodate the first optics group, the second optics group, and the actuating unit, the base comprising a boss configured to engage and maintain the first retaining element in a first rotary position, such that the rotation of the actuator is converted to translatory movement of the first retaining element from the first linear position to the second linear position, and to disengage the first retaining element when the first retaining element reaches the second linear position, such that the rotation of the actuator generates rotary movement of the first retaining element from the first rotary position to a second rotary position, in which second rotary position the first retaining element is movable from the second linear position to the first linear position by means of decompression of the resilient element, movement of the first retaining element from the second linear position to the first linear position generating the movement of the first optics group from the retracted position to the extended position.

Such a solution allows the use of an actuating unit that is fast, impact resistant, and wherein any unwanted clearances between components are removed. Furthermore, since the resilient element of the actuating unit is decompressed, or at least only partially compressed, also when the first optics group is in the retracted position, the properties of the resilient element remain unaffected, ensuring the resilient element does not weaken over time.

In a possible implementation form of the first aspect, the actuating unit is configured to generate movement of at least the first optics group from the extended position to the retracted position, the actuator being configured to rotate around the optical axis in a second direction, the first retaining element being configured to translate along the optical axis and to rotate around the optical axis in response to the rotation of the actuator, the second retaining element being configured to rotate from the disengaged position to the engaged position, the boss of the base being configured to engage and maintain the first retaining element in the second rotary position, such that the rotation of the actuator is converted to translatory movement of the first retaining element from the first linear position to the second linear position, movement of the first retaining element from the first linear position to the second linear position generating the movement of the first optics group from the extended position to the retracted position, and to disengage the first retaining element when the first retaining element reaches the second linear position, such that the rotation of the actuator generates rotary movement of the first retaining element from the second rotary position to the first rotary position, in which first rotary position the first retaining element is movable from the second linear position to the first linear position by means of decompression of the resilient element. This allows the very same components to be used, with the same advantages, for moving the first optics group from the extended position to the retracted position as well as from the retracted position to the extended position.

In a further possible implementation form of the first aspect, the first optics group comprises at least one lens and a first housing and the second optics group comprises at least one lens and a second housing, facilitating a range of different optical performances.

In a further possible implementation form of the first aspect, the first retaining element comprises a first groove, the second retaining element comprises a second groove, and the first housing comprises at least one tongue configured to engage one of the first groove and the second groove, the first groove and the second groove being configured to align when the first retaining element is in the second linear position and the second retaining element is in the engaged position, allowing the tongue to slide from the second groove to the first groove such that the first optics group can be released from the second retaining element and movement of the first optics group from the retracted position to the extended position is allowed, the first groove and the second groove being configured to misalign when the first retaining element is in the first linear position and the second retaining element is in the engaged position, allowing the tongue to engage the second groove such that the second retaining element maintains the first optics group in the retracted position. This allows the first optics group to be locked safely into place when in the retracted position, while still allowing the first optics group to move to an extended position with reliability and precision. In a further possible implementation form of the first aspect, one of the base and the first housing comprises a slot extending parallel with the optical axis and the other of the base and the first housing comprises a protrusion engaging the slot, the slot comprising oppositely arranged closed ends limiting a range of movement of the protrusion within the slot and limiting a range of movement of the first optics group relative the base along the optical axis. This facilitates repeatable and reliable movement of the first housing without clearance along the optical axis, while preventing rotation of the first housing around the optical axis.

In a further possible implementation form of the first aspect, the translatory movement of the first retaining element in a first direction along the optical axis, from the first linear position to the second linear position, generates compression of the resilient element, and the translatory movement of the first retaining element in a second direction along the optical axis, from the second linear position to the first linear position, facilitates decompression of the resilient element, allowing movement to be generated by means of decompression.

In a further possible implementation form of the first aspect, the degree of compression of the resilient element is larger in the second compression state than in the first compression state, reducing the long-term effect that compression has on the resilient element when in the first compression state.

In a further possible implementation form of the first aspect, the resilient element is configured to transfer the rotation of the first retaining element to the second retaining element, or the first retaining element and the second retaining element are interlocked by means of first and second mechanically engaging parts, the first and second mechanically engaging parts being configured to transfer the rotation of the first retaining element to the second retaining element, providing different options for interconnecting the first retaining element and the second retaining element.

In a further possible implementation form of the first aspect, the actuator comprises a first actuating element configured to rotate around the optical axis and to, when rotating in the first direction, apply force onto a surface of the first retaining element extending at a first angle to the optical axis, the force pushing the first retaining element from the first linear position to the second linear position. Such a solution is simple and does not rely on separately moveable parts to transfer rotational movement to linear movement. In a further possible implementation form of the first aspect, the first actuating element is configured to, when rotating in the second direction, allow the first retaining element to move from the second linear position to the first linear position. This allows the resilient element to be decompressed regardless of the position of the first optics group.

In a further possible implementation form of the first aspect, the first retaining element comprises a first cam surface extending at a first angle to the optical axis and a second cam surface extending at a second angle to the optical axis, the first actuating element comprising a first cam surface extending at a first angle to the optical axis and a second cam surface extending at a second angle to the optical axis, the first cam surfaces being in abutment with each other along a first contact axis and the second cam surfaces being in abutment with each other along a second contact axis when the first retaining element is in the first linear position, and the first cam surfaces being offset relative each other along the first contact axis and the second cam surfaces being offset relative each other along the second contact axis when the first retaining element is in the second linear position. This solution is simple and does not rely on separately moveable parts to transfer rotational movement to linear movement along the optical axis as well as rotary movement around the optical axis.

In a further possible implementation form of the first aspect, the first cam surface and the second cam surface of the first retaining element together form a v-shaped recess, the first cam surface and the second cam surface of the first actuating element forming a v-shaped protrusion, the v- shaped recess and the v-shaped protrusion being arranged such that the v-shaped recess completely encloses the v-shaped protrusion when the first retaining element is in the first linear position. Such a symmetrical configuration provides a simple and reliable solution for generating translatory and/or rotary movement of the first retaining element.

In a further possible implementation form of the first aspect, the actuator comprises a second actuating element, the first actuating element being configured to rotate around the optical axis in response to the rotation of the second actuating element. This allows the first actuating element to be rotated both clockwise and anticlockwise.

In a further possible implementation form of the first aspect, the second actuating element is configured to be rotated by means of external force, the second actuating element and the first actuating element being configured to interlock by means of third and fourth mechanically engaging parts, the third and fourth mechanically engaging parts being configured to allow the second actuating element to rotate at a different angle around the optical axis than the first actuating element. This allows adjustments to be made by a user, manually or via an actuator.

In a further possible implementation form of the first aspect, when the first optics group has reached the extended position, the actuator is configured such that the rotation of the first actuating element in the first direction is stopped and the second actuating element is rotated in the second direction, and the first actuating element is configured to engage the base such that the rotation of the second actuating element in the second direction is converted to translatory movement of the first actuating element, and the second optics group, in the first direction along the optical axis. This allows auto-focus functionality to be provided without needing a further, separate actuator.

In a further possible implementation form of the first aspect, the first housing of the first optics group is configured to, when the first optics group has reached the extended position, engage the second housing of the second optics group such that the first optics group and the second optics group are translated simultaneously along the optical axis, allowing the distance between the first optics group and the second optics group to be maintained also when autofocus is applied.

In a further possible implementation form of the first aspect, the second actuating element comprises an inner thread configured to engage an outer thread of the first actuating element, facilitating simple, effective, and reliable interconnection and movement of the first actuating element along the optical axis.

In a further possible implementation form of the first aspect, one of the base and the first actuating element comprises a slot extending parallel with the optical axis and the other of the base and the first actuating element comprises a protrusion engaging the slot and limiting a range of movement of the second optics group relative the base along the optical axis, allowing the second optics group to be moved, facilitating autofocus, and also preventing rotation around the optical axis. According to a second aspect, there is provided an electronic apparatus comprising the optical arrangement according to the above. This allows an electronic device provided with an actuating unit that is fast, impact resistant, without unwanted clearances between components, and maintains its efficiency over time.

These and other aspects will be apparent from the embodiment s) described below.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following detailed portion of the present disclosure, the aspects, embodiments, and implementations will be explained in more detail with reference to the example embodiments shown in the drawings, in which:

Fig. 1 shows a perspective view of parts of an optical arrangement in accordance with an example of the embodiments of the disclosure, wherein the first optics group of the optical arrangement is in a retracted position;

Fig. 2 shows a perspective view of parts of an optical arrangement in accordance with an example of the embodiments of the disclosure, wherein the first optics group of the optical arrangement is in an extended position;

Fig. 3 shows a further perspective view of parts of an optical arrangement in accordance with an example of the embodiments of the disclosure, wherein the first optics group of the optical arrangement is in a retracted position;

Fig. 4 shows a side view of parts of an optical arrangement in accordance with an example of the embodiments of the disclosure, wherein the first optics group of the optical arrangement is in an extended position;

Fig. 5 shows a further side view of parts of an optical arrangement in accordance with an example of the embodiments of the disclosure, wherein the first optics group of the optical arrangement is in an extended position;

Figs. 6a to 6c show perspective views of a first retaining element and a second retaining element in accordance with an example of the embodiments of the disclosure;

Fig. 7 shows a partially exploded, perspective view of an actuating unit in accordance with an example of the embodiments of the disclosure;

Fig. 8 shows a perspective view of an actuator and a second optics group in accordance with an example of the embodiments of the disclosure;

Figs. 9a to 9c show perspective views parts of an actuator in accordance with an example of the embodiments of the disclosure; Figs. 10a to 10c show side views of an optical arrangement in accordance with an example of the embodiments of the disclosure, wherein the first optics group is in a retracted position and the resilient element is in a substantially decompressed state, wherein the first optics group is in a retracted position and the resilient element is in a compressed state, and wherein the first optics group is in an extended position and the resilient element is in a substantially decompressed state.

DETAILED DESCRIPTION

The present invention relates to an electronic apparatus such as a smartphone, tablet, camera, projector, and similar comprising an optical arrangement 1 as described below.

The present invention also relates to an optical arrangement 1 comprising a first optics group 3 and a second optics group 4 together defining an optical axis Al, an actuating unit 5 configured to generate movement of at least the first optics group 3 from a retracted position Pl to an extended position P2 along the optical axis Al, the actuating unit 5 comprising an actuator 6 configured to rotate around the optical axis Al in a first direction DI, a first retaining element 7 configured to translate along the optical axis Al and to rotate around the optical axis Al in response to the rotation of the actuator 6, a second retaining element 8 configured to rotate, in response to the rotation of the first retaining element 7, from an engaged position P3, wherein the second retaining element 8 engages and maintains the first optics group 3 in the retracted position Pl, to a disengaged position P4, wherein the first optics group 3 is released, allowing movement of the first optics group 3 from the retracted position Pl to the extended position P2, a resilient element 9 being in a first compression state SI when the first retaining element 7 in a first linear position LI along the optical axis Al and in a second compression state S2 when the first retaining element 7 is in a second linear position L2 along the optical axis Al, a base 10 configured to accommodate the first optics group 3, the second optics group 4, and the actuating unit 5, the base comprising a boss 11 configured to engage and maintain the first retaining element 7 in a first rotary position Rl, such that the rotation of the actuator 6 is converted to translatory movement of the first retaining element 7 from the first linear position LI to the second linear position L2, and to disengage the first retaining element 7 when the first retaining element 7 reaches the second linear position L2, such that the rotation of the actuator 6 generates rotary movement of the first retaining element 7 from the first rotary position Rl to a second rotary position R2, in which second rotary position R2 the first retaining element 7 is movable from the second linear position L2 to the first linear position LI by means of decompression of the resilient element 9, movement of the first retaining element 7 from the second linear position L2 to the first linear position LI generating the movement of the first optics group 3 from the retracted position Pl to the extended position P2.

Figs. 10a to 10c illustrate the optical arrangement 1 as well as the relative movement of some of its components as the first optics group 3 is moved from the retracted position Pl to the extended position P2 along the optical axis Al.

As shown in Fig. 4, a first optics group 3 and a second optics group 4 together define the optical axis Al. The first optics group 3 may comprise at least one lens 3a and a first housing 3b, and the second optics group 4 may comprise at least one lens 4a and a second housing 4b.

A base 10 is configured to accommodate the first optics group 3, the second optics group 4, and an actuating unit 5, as illustrated in Figs. 1 to 3 and 7.

The actuating unit 5, illustrated in Figs. 10 to 10c, is configured to generate the movement of at least the first optics group 3 from the retracted position Pl to the extended position P2 along the optical axis Al. The actuating unit 5 comprises an actuator 6, a first retaining element 7, a second retaining element 8, and a resilient element 9.

The actuator 6 is configured to rotate around the optical axis Al in a first direction DI, as illustrated in Figs. 9a, 10a, and 10b, as well as in a second direction D2.

The first retaining element 7 is configured to translate along the optical axis Al and to rotate around the optical axis Al, simultaneously or independently of the translatory movement, in response to the rotation of the actuator 6 in the first direction DI, as illustrated in Figs. 10a to 10c.

The second retaining element 8 is configured to rotate, in response to the rotation of the first retaining element 7 from an engaged position P3, shown in Fig. 10a, to a disengaged position P4, shown in Fig. 10c. While in the engaged position P3, the second retaining element 8 engages and maintains the first optics group 3 in the retracted position Pl. When in the disengaged position P4, the first optics group 3 is released which allows movement of the first optics group 3 from the retracted position Pl to the extended position P2. The first retaining element 7 may comprise a first groove 12a and the second retaining element 8 may comprise a second groove 12b, as illustrated in Figs. 6a to 6c. The first housing 3b may comprise at least one tongue 12c, shown in Fig. 5, configured to engage one of the first groove 12a and the second groove 12b. The first groove 12a and the second groove 12b are configured to align when the first retaining element 7 is in the second linear position L2 and the second retaining element 8 is in the engaged position P3, as shown in Fig. 6a, allowing the tongue 12c to slide from the second groove 12b to the first groove 12a such that the first optics group 3 can be released from the second retaining element 8 allowing movement of the first optics group 3 from the retracted position Pl to the extended position P2. The first groove 12a and the second groove 12b are also configured to misalign when the first retaining element 7 is in the first linear position LI and the second retaining element 8 is in the engaged position P3, allowing the tongue 12c to engage the second groove 12b such that the second retaining element 8 maintains the first optics group 3 in the retracted position Pl.

The translatory movement of the first retaining element 7 in the first direction D3 along the optical axis Al, from the first linear position LI to the second linear position L2, may generate compression of the resilient element 9, and the corresponding translatory movement of the first retaining element 7 in the second direction D4 along the optical axis Al, from the second linear position L2 to the first linear position LI, may facilitate decompression of the resilient element 9.

The resilient element 9 is in a first compression state SI when the first retaining element 7 in a first linear position LI along the optical axis Al and in a second compression state S2 when the first retaining element 7 is in a second linear position L2 along the optical axis Al . In other words, the resilient element 9, e.g. a spring, is compressed to different degrees depending on which linear position along the optical axis Al the first retaining element 7 is in at the moment. The degree of compression of the resilient element 9 may be larger in the second compression state S2 than in the first compression state SI. The resilient element 9 may be completely decompressed when in the first compression state SI, however, it may also be somewhat compressed. The resilient element 9 may be a coil spring and it may be fixed to the underside of the first retaining element 7. The resilient element 9 may be configured to transfer the rotation of the first retaining element 7 to the second retaining element 8.

Alternatively, the first retaining element 7 and the second retaining element 8 may be interlocked by means of first and second mechanically engaging parts 19a, 19b, as illustrated in Figs. 6a to 6c. The first and second mechanically engaging parts 19a, 19b are configured to transfer the rotation of the first retaining element 7 to the second retaining element 8. The first and second mechanically engaging parts 19a, 19b may comprise of a number of surface deviations or edges which abut when the first retaining element 7 is in the second linear position L2 such that the first retaining element 7 and the second retaining element 8 partially overlap, i.e. the second retaining element 8 is partially nested within the first retaining element 7.

The base 10 comprises a boss 11, see Figs. 1 to 3, configured to lock and release the first retaining element 7. The boss 11 locks the first retaining element 7 in a first rotary position Rl, such that the rotation of the actuator 6 is converted to translatory movement of the first retaining element 7 from the first linear position LI to the second linear position L2, as illustrated in Figs. 10a and 10b. As illustrated in Fig. 6b, the inner surface of the first retaining element 7 may comprise an additional boss 23a configured to be arranged between boss 11 and an edge 23b of a cut-out in the second retaining element 8, this arrangement effectively preventing the first retaining element 7 from rotating.

The boss 11 releases the first retaining element 7 when the first retaining element 7 reaches the second linear position L2, allowing the rotation of the actuator 6 to generate rotary movement of the first retaining element 7 from the first rotary position Rl to a second rotary position R2, as illustrated in Fig. 10c. The first retaining element 7 may be released since, in the second linear position L2, the additional boss 23a has been moved such that it extends completely underneath boss 11.

When in the second rotary position R2, the first retaining element 7 is movable from the second linear position L2 back to the first linear position LI by means of decompression of the resilient element 9. The movement of the first retaining element 7 from the second linear position L2 to the first linear position LI generates movement of the first optics group 3 from the retracted position Pl to the extended position P2, as illustrated in Figs. 10a to 10c. The actuating unit 5 may furthermore be configured to generate movement of at least the first optics group 3 from the extended position P2 to the retracted position Pl, a movement which is shown in Figs. 10c to 10a. In such an embodiment, the actuator 6 is configured to rotate around the optical axis Al in a second direction D2 and the second retaining element 8 is configured to rotate from the disengaged position P4 to the engaged position P3. The boss 11 of the base 10 is configured to lock the first retaining element 7 in the second rotary position R2, such that the rotation of the actuator 6 is converted to translatory movement of the first retaining element 7 from the first linear position LI to the second linear position L2. The movement of the first retaining element 7 from the first linear position LI to the second linear position L2 generates movement of the first optics group 3 from the extended position P2 to the retracted position PL The boss 11 is also configured to release the first retaining element 7 when the first retaining element 7 reaches the second linear position L2, such that the rotation of the actuator 6 generates rotary movement of the first retaining element 7 from the second rotary position R2 to the first rotary position Rl. When in the first rotary position Rl, the first retaining element 7 is movable from the second linear position L2 to the first linear position LI by means of decompression of the resilient element 9.

One of the base 10 and the first housing 3b may comprise a slot 13 extending parallel with the optical axis Al and the other of the base 10 and the first housing 3b comprises a protrusion 14 engaging the slot 13, as illustrated in Fig. 2. The slot 13 comprises oppositely arranged closed ends limiting the range of movement of the protrusion 14 within the slot 13 and, hence, limiting the range of movement of the first optics group 3 relative the base 10 along the optical axis Al.

The actuator 6 may comprise a first actuating element 6a configured to rotate around the optical axis Al and to, when rotating in the first direction DI, apply force F onto a surface 15a of the first retaining element 7 extending at a first angle a to the optical axis Al, as illustrated in Figs. 10b and 10c. The force F pushes the first retaining element 7 from the first linear position LI to the second linear position L2.

The first actuating element 6a may also be configured to, when rotating in the second direction D2, allow the first retaining element 7 to move from the second linear position L2 to the first linear position LI. One of the base 10 and the first actuating element 6a may comprise a slot 17 extending parallel with the optical axis Al and the other of the base 10 and the first actuating element 6a comprises a protrusion 18 engaging the slot 17 and limiting a range of movement of the second optics group 4 relative the base 10 along the optical axis Al, as shown in Fig. 3.

The first retaining element 7 may comprise a first cam surface 15a extending at a first angle a to the optical axis Al and a second cam surface 15b extending at a second angle P to the optical axis Al. Correspondingly, the first actuating element 6a may comprise a first cam surface 16a extending at a first angle a to the optical axis Al and a second cam surface 16b extending at a second angle P to the optical axis Al, as illustrated in Fig. 10c. The first cam surfaces 15a, 16a are in abutment with each other along a first contact axis A2 and the second cam surfaces 15b, 16b are in abutment with each other along a second contact axis A3 when the first retaining element 7 is in the first linear position LI, see Figs. 10a and 10c. The first cam surfaces 15a, 16a are offset relative each other along the first contact axis A2 and the second cam surfaces 15b, 16b are offset relative to each other along the second contact axis A3 when the first retaining element 7 is in the second linear position L2, see Fig. 10b.

The first cam surface 15a and the second cam surface 15b of the first retaining element 7 may together form a v-shaped recess, as shown in Fig. 4, and correspondingly the first cam surface 16a and the second cam surface 16b of the first actuating element 6a may form a v-shaped protrusion, see Fig. 9c. The v-shaped recess and the v-shaped protrusion are arranged such that the v-shaped recess completely encloses the v-shaped protrusion when the first retaining element 7 is in the first linear position LI, as shown in Figs. 10a and 10c. Nevertheless, the cam surfaces 15a, 15b, 16a, and 16b may have any suitable shapes.

The actuator 6 may also comprise a second actuating element 6b, shown in Figs. 7 to 9c, the first actuating element 6a being configured to rotate around the optical axis Al in response to the rotation of the second actuating element 6b. The second actuating element 6b is configured to be rotated by means of external force, the second actuating element 6b and the first actuating element 6a being configured to interlock by means of third and fourth mechanically engaging parts 20a, 20b, as shown in Figs 9b and 9c. The third and fourth mechanically engaging parts 20a, 20b are configured to allow the second actuating element 6b to rotate at a different angle around the optical axis Al than the first actuating element 6a. When the first optics group 3 has reached the extended position P2, as shown in Fig. 10c, the actuator 6 may be configured such that rotation of the first actuating element 6a in the first direction DI is stopped and the second actuating element 6b is rotated in the second direction D2. The first actuating element 6a is configured to engage the base 10 such that the rotation of the second actuating element 6b in the second direction D2 is converted to translatory movement of the first actuating element 6a, and the second optics group 4, in the first direction D3 along the optical axis Al.

The first housing 3b of the first optics group 3 may be configured to, when the first optics group 3 has reached the extended position P2, engage the second housing 4b of the second optics group 4 such that the first optics group 3 and the second optics group 4 are translated simultaneously along the optical axis Al.

The second actuating element 6b may comprise an inner thread 21a configured to engage an outer thread 22a of the first actuating element 6a, see Figs. 3, 8, and 9c.

The various aspects and implementations have been described in conjunction with various embodiments herein. However, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed subject-matter, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage.

The reference signs used in the claims shall not be construed as limiting the scope. Unless otherwise indicated, the drawings are intended to be read (e.g., cross-hatching, arrangement of parts, proportion, degree, etc.) together with the specification, and are to be considered a portion of the entire written description of this disclosure. As used in the description, the terms “horizontal”, “vertical”, “left”, “right”, “up” and “down”, as well as adjectival and adverbial derivatives thereof (e.g., “horizontally”, “rightwardly”, “upwardly”, etc.), simply refer to the orientation of the illustrated structure as the particular drawing figure faces the reader. Similarly, the terms “inwardly” and “outwardly” generally refer to the orientation of a surface relative to its axis of elongation, or axis of rotation, as appropriate.