U.S. patent application number 14/255865 was filed with the patent office on 2014-08-14 for radio-transparent coating for electronic device housing.
This patent application is currently assigned to APPLE INC.. The applicant listed for this patent is APPLE INC.. Invention is credited to Evans Hankey, Naoto Matsuyuki, David A. Pakula, Douglas Weber.
Application Number | 20140225489 14/255865 |
Document ID | / |
Family ID | 42117278 |
Filed Date | 2014-08-14 |
United States Patent
Application |
20140225489 |
Kind Code |
A1 |
Weber; Douglas ; et
al. |
August 14, 2014 |
RADIO-TRANSPARENT COATING FOR ELECTRONIC DEVICE HOUSING
Abstract
Electronic devices and other apparatuses adapted to receive
electromagnetic wave communications are disclosed. An outer housing
encloses various device components, including at least an internal
antenna located fully therewithin and adapted to receive/send
communications from/to an outside source via RF or other
electromagnetic waves. A ceramic coating can be a thermal spray
coating that covers at least a portion of the outer surface
proximate to the internal antenna, and can be "RF
transparent"--adapted to allow communications to/from the internal
antenna via electromagnetic waves. The outer housing can be
plastic, metal or a combination thereof. For metal or other non-RF
transparent housings, an RF-transparent insert can be fitted into a
window in the housing to permit communications to the internal
antenna. The ceramic coating covers some or all of the metal,
plastic and/or insert that comprise the outer housing and surface
for a final aesthetic finish to the device.
Inventors: |
Weber; Douglas; (Arcadia,
CA) ; Matsuyuki; Naoto; (Kasugai, JP) ;
Pakula; David A.; (San Francisco, CA) ; Hankey;
Evans; (San Francisco, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
APPLE INC. |
Cupertino |
CA |
US |
|
|
Assignee: |
APPLE INC.
Cupertino
CA
|
Family ID: |
42117278 |
Appl. No.: |
14/255865 |
Filed: |
April 17, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13452253 |
Apr 20, 2012 |
8738099 |
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14255865 |
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12343335 |
Dec 23, 2008 |
8185166 |
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13452253 |
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61108460 |
Oct 24, 2008 |
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Current U.S.
Class: |
312/223.1 ;
29/460 |
Current CPC
Class: |
H01Q 1/243 20130101;
Y10T 29/49888 20150115; H05K 5/0247 20130101 |
Class at
Publication: |
312/223.1 ;
29/460 |
International
Class: |
H05K 5/02 20060101
H05K005/02 |
Claims
1. A housing for an electronic device, the housing comprising: a
first portion configured to house an internal antenna adapted to
communicate via radio frequency waves, the first portion having a
first surface; a second portion having a second surface, wherein
the second surface is positioned adjacent the first surface at a
junction region, wherein at least one of the first portion and
second portion is transparent to radio frequency waves; and a radio
frequency transparent coating disposed on the first surface and the
second surface including the junction region such that the junction
region is not visible through the radio frequency transparent
coating, wherein the radio frequency transparent coating is
comprised of a radio frequency transparent material allowing
passage of radio frequency communication of the internal antenna,
wherein the radio frequency transparent coating has an outer
surface corresponding to an exterior surface portion of the
housing, the outer surface being seamless and having a continuous
metallic appearing finish.
2. The housing of claim 1, wherein the metallic appearing radio
frequency transparent coating is conformally disposed on the first
surface and the second surface.
3. The housing of claim 1, wherein the radio frequency transparent
coating has a hardness greater than a hardness of the first portion
and a hardness of the second portion.
4. The housing of claim 1, wherein the outer surface of the radio
frequency transparent coating comprises a ceramic material.
5. The housing of claim 1, wherein the outer surface has a polished
finish.
6. The housing of claim 1, wherein the one of the first portion and
the second portion includes a corner, wherein the radio frequency
transparent coating is disposed on a surface of the corner.
7. The housing of claim 1, wherein the electronic device is a
portable electronic device.
8. A housing for an electronic device, housing comprising: a
substrate having a shape suitable for housing an internal antenna
adapted to communicate via radio frequency waves, the substrate
comprised of a first radio frequency transparent material; and a
metallic appearing coating disposed on the housing such that the
substrate is not visible through the metallic appearing coating,
the metallic appearing coating comprised of a second radio
frequency transparent material different than the first radio
frequency transparent material, wherein the metallic appearing
coating is characterized as having a hardness greater than a
hardness of the first radio frequency transparent material, wherein
radio frequency communication of the internal antenna passes
through the substrate and the metallic appearing coating, wherein
the metallic appearing coating has an outer surface corresponding
to an exterior surface portion of the housing, the outer surface
having a uniform and seamless appearance.
9. The housing of claim 8, wherein the substrate comprises at least
one of ceramic, glass and plastic.
10. The housing of claim 8, wherein the substrate includes a
corner, wherein the metallic appearing coating is conformally
disposed on the corner.
11. The housing of claim 8, wherein the second radio frequency
transparent material comprises a melted powder.
12. The housing of claim 8, wherein the second radio frequency
transparent material is characterized has having a greater
stiffness than the first radio frequency transparent material.
13. The housing of claim 8, wherein the internal antenna is located
fully within the housing.
14. A method of forming a housing for an electronic device, the
method comprising: providing a first portion of the housing, the
first portion having a shape suitable for enclosing an internal
antenna adapted to communicate via radio frequency waves, the first
portion having a first surface; combining a second portion of the
housing with first portion such that a second surface of the second
portion is adjacent the first surface of the first portion at a
junction region, wherein the second portion is transparent to radio
frequency waves; and forming a coating on the first surface and the
second surface including the junction region such that the junction
region is not visible through the coating, wherein the coating is
comprised of a radio frequency transparent material such that radio
frequency communication of the internal antenna passes through the
second portion and through the coating, wherein the coating has an
outer surface corresponding to an exterior surface portion of the
housing, the outer surface being seamless and having a continuous
metallic appearing finish.
15. The method of claim 14, wherein the coating has a hardness
greater than a hardness of the first portion and a hardness of the
second portion.
16. The method of claim 14, wherein forming the coating includes
creating a conformal coating on the first surface and the second
surface.
17. The method of claim 14, wherein the first portion includes a
corner, wherein forming a coating includes forming the coating on a
surface of the corner.
18. The method of claim 14, further comprising: forming a polished
surface by polishing the outer surface of the coating.
19. The method of claim 14, wherein the internal antenna is fully
enclosed within the housing.
20. The method of claim 14, further comprising: aligning the
internal antenna within the housing such that the radio frequency
communication of the internal antenna passes through the second
portion and through the coating.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation of U.S. patent application Ser. No.
13/452,253 filed Apr. 20, 2012, entitled "THERMAL SPRAY COATING FOR
SEAMLESS AND RADIO-TRANSPARENT ELECTRONIC DEVICE HOUSING," which is
a continuation of U.S. patent application Ser. No. 12/343,335,
filed Dec. 23, 2008, entitled "THERMAL SPRAY COATING FOR SEAMLESS
AND RADIO-TRANSPARENT ELECTRONIC DEVICE HOUSING," which claims
priority to U.S. Provisional Patent Application No. 61/108,460,
filed Oct. 24, 2008, entitled "THERMAL SPRAY COATING FOR SEAMLESS
AND RADIO-TRANSPARENT ELECTRONIC DEVICE HOUSING," which is
incorporated herein by reference in its entirety and for all
purposes.
FIELD
[0002] The present invention relates generally to portable
computing devices, and more particularly to the formation of outer
housings for such portable computing or other personal devices.
BACKGROUND
[0003] Portable computing devices, such as media players, cellular
telephones, PDAs and the like, are becoming omnipresent. With a
multitude of manufacturers competing for sales of these devices in
retail markets, the need to provide state of the art features and
content on a device that very aesthetically pleasing is increasing.
This is particularly true given the nature of consumers to desire
portable computing devices that are "hip" or "cool" looking, with
many purchasing decisions for such devices being affected by this
particular desire. Accordingly, the outer look or feel of a
portable computing device can be a critical factor in device
design.
[0004] One design challenge associated with portable computing
devices is the composition and appearance of the outer housing or
enclosure that is used to house the various internal components of
the portable computing device. A seamless, smooth and/or sleek look
is often highly desired, with metal or other similar materials
being preferable. Some solutions to these issues have involved the
use of an outer housing that is tubular in nature. Various examples
of and methods of manufacturing such tubular outer housings can be
found in, for example, commonly owned U.S. patent application Ser.
Nos. 10/884,172 and 11/501,184, filed on Jul. 2, 2004, and Oct. 7,
2006 respectively, both of which are entitled "HANDHELD COMPUTING
DEVICE," and both of which are incorporated by reference herein in
their entireties and for all purposes. Such outer housings can be
used on, for example the iPod.RTM. media player or iPhone.RTM.
cellular telephone made by Apple Inc., among other suitable
portable computing devices or items.
[0005] One drawback to a common approach of manufacturing a
generally metallic outer housing for a portable computing device is
that metal can be a poor material choice where electromagnetic wave
transmissions through the material are desired. For example, a
cellular telephone that requires radio frequency transmissions to
operate must either have an external antenna or a region in the
housing through which radio waves can pass. As a more detailed
example, because no external antenna was used on the iPhone.RTM. 2G
cellular telephone made by Apple Inc., its metallic outer housing
included a plastic portion located proximate to an internal antenna
or receiver region. This design permitted most of the outer housing
to be aluminum, but also required a smaller region of plastic to
allow for radio frequency communications through the outer
housing.
[0006] Unfortunately, the use of two different materials for the
outer housing results in a seam between the materials, as well as
the likelihood of a two-toned look in the overall look of the
device. One solution to avoid such seams and two-toned appearances
can be to use an outer housing that is comprised entirely of a
"radio transparent" material, such as a hard plastic. One drawback
to this approach, however, is that metallic surface finishes are
thought by some to be more aesthetically pleasing than plastic
surface finishes. In general, metallic surface finishes have a look
and feel that tends to be harder, smoother and sleeker than plastic
surface finishes. Thus, with respect to a portable electronic
device that must be able to communicate via electromagnetic waves,
a designer has traditionally needed to choose at least one of the
lesser aesthetically pleasing alternatives involving an external
antenna, a seam or seams on the outer housing, or an outer housing
made entirely of plastic or some other radio transparent
material.
[0007] While many designs and methods of manufacture for providing
outer housings on portable computing devices and other similar
items have generally worked well in the past, there is always a
desire to provide new and improved designs that result in
aesthetically pleasing and functional outer housings for such
portable computing devices. In particular, it is desirable to
provide a portable computing device that can communicate via
electromagnetic waves, have an internal antenna, have no seams in
the outer housing, and have an outer housing with a sleek and hard
finish that is metallic or similar thereto.
SUMMARY
[0008] It is an advantage of the present invention to provide an
aesthetically pleasing outer housing for a portable computing
device, such as a cellular telephone or media player. Such an outer
housing should be usable for a portable computing device adapted to
communicate via electromagnetic waves, have an internal antenna,
have no seams in the outer housing, and have an outer housing with
a sleek and hard finish that is metallic or similar thereto. This
can be accomplished at least in part through the use of a ceramic
thermal spray coating that is applied to the outer surface or
surfaces of one or more outer housing components of the computing
device.
[0009] In various embodiments, the invention can include an
electronic device having an outer housing configured to enclose at
least a portion of the electronic device and having an outer
surface, an internal antenna located fully within the outer
housing, said receiver being adapted to receive communications from
an outside source via electromagnetic waves, and a ceramic coating
that covers at least a portion of the outer surface proximate the
internal antenna, wherein the ceramic coating is adapted to allow
communications to the internal antenna via electromagnetic
waves.
[0010] In various detailed embodiments, a portable, handheld,
personal computing device is provided. This device can include a
plurality of internal operational components adapted to provide
processing for a user thereof, a metal outer housing configured to
enclose at least a portion of the internal operational components,
said metal outer housing having a first outer surface and an
opening therethrough, an internal antenna located fully within the
metal outer housing, said internal antenna being adapted to receive
communications from an outside source via radio frequency waves, a
processor located within the metal outer housing and coupled to the
internal antenna, said processor being adapted to provide an output
for a user as a result of communications from an outside source, an
insert fitted within the opening in the metal outer housing such
that a seam between the metal outer housing and the insert is
formed, said insert being transparent to radio frequency waves and
having a second outer surface, and a ceramic coating that covers
the first outer surface and second outer surface such that the seam
is hidden thereby, wherein said ceramic coating is also transparent
to radio frequency waves.
[0011] In various embodiments, a radio transparent ceramic coating
can be applied using a thermal spray process. This allows for the
use of a plastic or other radio transparent material, such that an
internal antenna can be used, and also results in a hard and sleek
ceramic finish for the outer housing. Any seam or seams between
different outer housing components can be covered by the thermal
spray ceramic material to provide a final seamless ceramic look and
finish.
[0012] Other apparatuses, methods, features and advantages of the
invention will be or will become apparent to one with skill in the
art upon examination of the following figures and detailed
description. It is intended that all such additional systems,
methods, features and advantages be included within this
description, be within the scope of the invention, and be protected
by the accompanying claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The included drawings are for illustrative purposes and
serve only to provide examples of possible structures and
arrangements for the disclosed inventive apparatus and method for
providing an outer housing for a personal computing device by using
a thermal spray coating. These drawings in no way limit any changes
in form and detail that may be made to the invention by one skilled
in the art without departing from the spirit and scope of the
invention.
[0014] FIG. 1A illustrates in back plan view the obverse side of an
exemplary cellular telephone having a metal and plastic housing and
a two-toned overall appearance.
[0015] FIG. 1B illustrates in back plan view the obverse side of an
alternative exemplary cellular telephone having a fully plastic
outer housing and a uniform overall appearance.
[0016] FIG. 2A illustrates in partial top cross-sectional view an
exemplary cellular telephone having an internal antenna and a metal
housing.
[0017] FIG. 2B illustrates in partial top cross-sectional view an
alternative exemplary cellular telephone having an internal antenna
a metal and plastic housing.
[0018] FIG. 2C illustrates in partial top cross-sectional view
another alternative exemplary cellular telephone having an internal
antenna and a fully plastic or glass housing.
[0019] FIG. 3 illustrates in partial top cross-sectional view an
exemplary cellular telephone having an internal antenna, a fully
plastic housing and a thermal spray coating, according to one
embodiment of the present invention.
[0020] FIG. 4 illustrates in partial top cross-sectional view an
alternative exemplary cellular telephone having an internal
antenna, a metal and plastic housing and a thermal spray coating,
according to another embodiment of the present invention.
[0021] FIG. 5 illustrates in cross-sectional view an exemplary
thermal spray process and various aspects thereof.
DETAILED DESCRIPTION
[0022] Exemplary applications of apparatuses and methods according
to the present invention are described in this section. These
examples are being provided solely to add context and aid in the
understanding of the invention. It will thus be apparent to one
skilled in the art that the present invention may be practiced
without some or all of these specific details. In other instances,
well known process steps have not been described in detail in order
to avoid unnecessarily obscuring the present invention. Other
applications are possible, such that the following examples should
not be taken as limiting.
[0023] In the following detailed description, references are made
to the accompanying drawings, which form a part of the description
and in which are shown, by way of illustration, specific
embodiments of the present invention. Although these embodiments
are described in sufficient detail to enable one skilled in the art
to practice the invention, it is understood that these examples are
not limiting; such that other embodiments may be used, and changes
may be made without departing from the spirit and scope of the
invention.
[0024] The invention relates in various embodiments to
aesthetically pleasing outer housings for a portable personal
computing device, such as an iPod.RTM. media player or iPhone.RTM.
cellular telephone made by Apple Inc., among other suitable devices
or items. Such outer housings can be generally tubular and handheld
in nature, although the exact shape and size can vary. In addition,
such outer housings are preferably adapted to allow for the
transmission of electromagnetic waves, such that radio frequency
("RF") communications and other transmissions can be made through
the outer housing. Further, these outer housings are preferably
seamless, sleek and sufficiently hardened in look and feel.
[0025] In various embodiments of the present invention, an outer
housing for a portable personal computing device is provided.
Various embodiments may also include or relate to the entire
portable personal computing device. The outer housing can be
adapted to surround and protect a plurality of internal operational
components for the computing device. The outer housing can include
a single base component or a plurality of components assembled
together to form a uniform outer housing. The one or more base
components forming the outer housing can then be coated with a
thermally sprayed material that is radio transparent, such as a
ceramic. The thermally sprayed ceramic or other material can cover
any seams between outer housing components, such that the device
has a uniform, seamless, sleek and hardened finish that allows for
radio communications with an internal antenna.
[0026] Although it is contemplated that the internal antenna for
use with the present invention be fully or completely internal,
other arrangements may also be used. For example, a mostly internal
but partially external antenna may be used. Further, an extendable
antenna that can be at least partially external in one position and
fully internal in another position may also be used. This could
result in the user having an option to extend an antenna if
desired, while still providing good antenna service and reception
in a fully internal position. Other alternative internal, external
and combination antenna arrangements may be used, and the present
invention is contemplated to be used with respect to any and all
such arrangements.
[0027] Referring first to FIG. 1A, the obverse side of an exemplary
cellular telephone having a metal and plastic housing and a
two-toned overall appearance is illustrated in back plan view. As
shown, cellular telephone 10 has a back surface housing having an
aluminum component 11 and a plastic component 12, with the plastic
component being located proximate to an internal antenna 13, such
that RF transmissions can be made through the plastic component to
the antenna. Because two different materials are used, a seam 14
exists between these metal and plastic housing components. As noted
above, such a seam and two-toned appearance might be less
aesthetically pleasing to some that a uniform outer housing.
[0028] Moving next to FIG. 1B, the obverse side of an alternative
exemplary cellular telephone having a fully plastic outer housing
and a uniform overall appearance is shown in back plan view.
Cellular telephone 20 has a uniform plastic outer housing 21, such
that RF transmissions can be made therethrough in all locations.
However, as noted above, plastic finishes may be less aesthetically
pleasing to some than metallic or similar finishes. Although the
location of an internal antenna can be in the same general area as
that which is shown in FIG. 1A, it will be appreciated such an
internal antenna can be in virtually any other internal location,
since the use of an "RF transparent" plastic for the entire housing
provides flexibility in at least this regard.
[0029] Continuing to FIG. 2A-2C, various exemplary portable
computing devices are depicted. In FIG. 2A, an exemplary cellular
telephone having an internal antenna and a metal housing is shown
in partial top cross-sectional view. As shown, the X notations
indicate that no electromagnetic wave signal can be read by the
antenna from a particular location. As would be expected, metal
housing 11 generally does not allow for RF transmissions
therethrough with respect to internal antenna 13. As such, the
exemplary arrangement shown in FIG. 2A is generally impractical
without the use of an external antenna or some RF transparent
window in metal housing 11. The illustrated cross-section would be
appropriate to show what happens in locations where there is no RF
transparent window in a device housing, such as at the upper
portions of cellular telephone 10 shown in FIG. 1A.
[0030] FIG. 2B illustrates in partial top cross-sectional view an
alternative exemplary cellular telephone having an internal antenna
within a metal and plastic housing. As shown, the X notations
indicate that no electromagnetic wave signal can be read by the
antenna from a particular location, but the 0 notations indicate
that an electromagnetic wave signal from an outside source can be
read by the internal antenna. This arrangement generally
corresponds to that which is shown at the bottom portion of
cellular telephone 10 in FIG. 1A, in that RF transmissions to the
internal antenna 13 can be made through an RF transparent plastic
portion 12 of the outer housing, but not through the metal portion
11 of the outer housing. As such, it is preferable that the
internal antenna 13 be located proximate to the plastic portion 12
or other RF transparent region of the device.
[0031] FIG. 2C illustrates in partial top cross-sectional view
another alternative exemplary cellular telephone having an internal
antenna and a fully plastic or glass housing. This alternative
arrangement generally corresponds to that which is shown in FIG.
1B, in that RF transmissions to the internal antenna 13 can be made
through the entire plastic outer housing 21. As will be
appreciated, there can be various drawbacks either functionally or
aesthetically with respect to each of the embodiments shown in
FIGS. 2A-2C. In general, all of these drawbacks are overcome in the
various inventive embodiments disclosed and described herein.
[0032] Turning now to FIG. 3, an exemplary cellular telephone
having an internal antenna, a fully plastic, glass or other RF
transparent housing and a thermal spray coating is shown in partial
top cross-sectional view, according to one embodiment of the
present invention. Cellular telephone 100 has a fully internal
antenna 113, with such a fully internal antenna being located
entirely within the outer housing of the device. Although no
antenna component is located outside the outer housing, it will
appreciated that some embodiments may include such an element, as
noted above. A plastic outer housing component 121 can fully or
substantially house the entire cellular telephone 100, similar to
the plastic outer housing 21 of FIGS. 1B and 2C. In addition, a
thermal spray coating 130 is applied to the outer surface of
plastic housing 121. This thermal spray coating can be a material
that is radio (i.e., RF) transparent, such as ceramic, such that RF
communications from an outside source can transmit through both the
coating and plastic housing to reach the internal antenna. In some
embodiments, the coating can cover all or substantially all of the
plastic housing, such that a uniform and seamless surface is
provided. Such a surface can be smoother, stiffer, harder,
consistent and continuous than typical plastic materials, resulting
in a more aesthetically pleasing outer appearance of the
device.
[0033] FIG. 4 illustrates in partial top cross-sectional view an
alternative exemplary cellular telephone having an internal
antenna, a metal and plastic housing and a thermal spray coating,
according to another embodiment of the present invention. Cellular
telephone 200 can have a base outer housing component 211 made of
metal, with such a metal housing component having one or more
"windows" or openings therein. One or more inserts or other outer
housing components 212 can fit into these windows or openings,
preferably such that the surfaces are flush to create a mostly
smooth and continuous outer surface. Such an insert or other
housing component 212 can be an radio transparent material, such as
plastic or glass, and can be placed proximate to an internal
antenna 213, such that RF transmissions can be made from an outside
source, through the insert 212 and to the internal antenna 213.
[0034] Such an arrangement is generally similar to that which is
shown and described with respect to FIG. 1A above, with the
aluminum and plastic outer housing components necessarily forming a
seam between the two. Unlike the foregoing example, however,
cellular telephone 200 also has a thermal spray coating 230 applied
to the outer surfaces of both the metal housing component 211 and
the radio transparent insert or housing component 212. Again, this
thermal spray coating 230 can be a ceramic or other material that
is radio transparent, such that RF communications can be made
between an outside location and an internal antenna located
entirely within the outer housing of the device. Advantageously,
applying the thermal spray coating 230 results in a thin layer that
covers the metal outer housing component 211, the plastic or glass
insert or housing component 212, and any seams between the two. In
some embodiments, the coating can cover all or substantially all of
the metal and plastic housing components, such that a uniform and
seamless outer surface is provided. As in the above embodiment,
such a surface can be smoother, stiffer and harder than typical
plastic materials, resulting in a more aesthetically pleasing outer
appearance of the device while still permitting for RF
communications. Such a finish is thus more consistent and
continuous than that resulting from typical combinations of metal
and plastic materials, resulting in a more aesthetically pleasing
outer appearance of the device.
[0035] FIG. 5 illustrates in cross-sectional view an exemplary
thermal spray process and various aspects thereof. A thermal spray
process generally involves melting or otherwise breaking down a
coating material into a fine powder that is then sprayed onto a
surface using a plasma spray gun, a cross-section of which is
illustrated. In general, a plasma spray gun 1 can include a
negatively charged component 2 and a positively charged component 3
inside a housing 4 having an opening 5 for the ejection of thermal
spray material 6. This thermal spray material can be sprayed onto
an outside device 10, which results in the formation of a thermal
spray coating 9 on the device.
[0036] Various materials can be used in such a thermal spray
process, including metals, ceramics and cermets. Because metals and
cermets tend to be poor transmitters for RF communications, it is
preferable that the thermally sprayed material for use with the
present invention be a ceramic powder material. Such a ceramic can
be, for example, an aluminum based powder, a chromium oxide based
powder, a titania based powder or a zirconium oxide based powder,
among other suitable materials.
[0037] The ceramic thermal spray process contemplated for use with
the present invention can be that which is provided by any number
of vendors, such as, for example, Sulzer Metco of Westbury, N.Y.;
Tocalo Co., Ltd. of Kobe-shi, Japan; or Plasma Giken Koygo, Co.
Ltd., of Tokyo, Japan. Other vendors may also be used for this
process, as may be applicable. In general, any suitable thermal
spray process that involves the use of a plasma spray gun or other
similar device to effectively "paint" or coat a thin layer onto a
surface can be used with the present invention. In particular, such
a layer should be a ceramic or other radio transparent
material.
[0038] Although many typical thermal spray processes use powders
having granules on the order of 100 microns in diameter, it is
thought that granules of this size may be too large for an
aesthetically pleasing smooth surface finish on a portable
computing device, as described in detail above. As such, it is
contemplated that a thermal spray process using smaller granule
sizes can be used with for the present invention. For example, a
fine powder thermal spray can be used having granules that are
about 10 or even 5 microns in diameter, on average. This can result
in a smoother surface finish on the final product.
[0039] In some embodiments, particularly where granules of a larger
diameter are used in the thermal spray process, a finishing step
might be employed to polish or otherwise smooth out the outer
surface of the thermal spray layer after it has been applied to the
outer surface(s) of the outer housing component(s). For example, a
diamond powder sanding process might be used to polish or smooth
out the final outer surface. Such a final finishing step can
improve the overall look of the portable computing device to be as
aesthetically pleasing as possible.
[0040] Although the foregoing invention has been described in
detail by way of illustration and example for purposes of clarity
and understanding, it will be recognized that the above described
invention may be embodied in numerous other specific variations and
embodiments without departing from the spirit or essential
characteristics of the invention. Certain changes and modifications
may be practiced, and it is understood that the invention is not to
be limited by the foregoing details, but rather is to be defined by
the scope of the appended claims.
* * * * *