U.S. patent application number 14/979326 was filed with the patent office on 2017-06-22 for photoconductive multi-resonator chipless rfid.
The applicant listed for this patent is XEROX CORPORATION. Invention is credited to George A. Gibson, James R. Larson.
Application Number | 20170178059 14/979326 |
Document ID | / |
Family ID | 59066483 |
Filed Date | 2017-06-22 |
United States Patent
Application |
20170178059 |
Kind Code |
A1 |
Gibson; George A. ; et
al. |
June 22, 2017 |
PHOTOCONDUCTIVE MULTI-RESONATOR CHIPLESS RFID
Abstract
A chipless RFID transponder is disclosed. The transponder
comprises an antenna and a plurality of resonant structures that
together define a spectral signature of the RFID transponder. Each
of the resonant structures comprises conductive portions separated
by interstitial regions. A reversible photoconductive material is
disposed in the interstitial regions of the resonant structures
between the conductive portions. The photoconductive material is
positioned so as to shift the spectral signature of the RFID when
exposed to radiation.
Inventors: |
Gibson; George A.;
(Fairport, NY) ; Larson; James R.; (Fairport,
NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
XEROX CORPORATION |
NORWALK |
CT |
US |
|
|
Family ID: |
59066483 |
Appl. No.: |
14/979326 |
Filed: |
December 22, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G06K 19/0723 20130101;
G06K 19/0672 20130101; G06Q 10/087 20130101 |
International
Class: |
G06Q 10/08 20060101
G06Q010/08; G06K 19/07 20060101 G06K019/07 |
Claims
1. A chipless RFID transponder, comprising: an antenna and a
plurality of resonant structures that together define a spectral
signature of the RFID transponder, each of the resonant structures
comprising conductive portions separated by interstitial regions;
and a reversible photoconductive material disposed in the
interstitial regions of the resonant structures between the
conductive portions, the photoconductive material positioned so as
to shift the spectral signature of the RFID when exposed to
radiation, wherein the photoconductive material has a property of
having a first conductivity prior to being exposed to radiation at
a specified wavelength and a second conductivity that is different
from the first conductivity after being exposed to radiation at the
specified wavelength.
2. The chipless RFID transponder of claim 1, wherein the conductive
portions of each resonant structure are formed from a continuous
segment of electrically conductive material that is coplanar with
the interstitial regions.
3. (canceled)
4. The chipless RFID transponder of claim 1, wherein the
photoconductive material is an electrical insulator prior to being
exposed to radiation at the specified wavelength.
5. The chipless RFID transponder of claim 1, wherein the second
conductivity is higher than the first conductivity.
6. The chipless RFID transponder of claim 1, wherein the change in
value of the second conductivity relative to the first conductivity
is substantially linearly dependent on the intensity of the light
to which the photoconductive material is exposed.
7. The chipless RFID transponder of claim 1, wherein the value of
the second conductivity is substantially the same as the first
conductivity unless the photoconductor is exposed to radiation
having a threshold intensity.
8. The chipless RFID transponder of claim 1, further comprising at
least one of an optical filter or a converter disposed over the
plurality of resonant structures.
9. The chipless RFID transponder of claim 1, wherein the
photoconductive material is disposed on a plurality of the resonant
structures.
10. The chipless RFID transponder of claim 1, further comprising an
adhesive backing on which the RFID transponder is disposed.
11. The chipless RFID transponder of claim 1, further comprising a
security overlayer.
12. The chipless RFID transponder of claim 1, wherein the
photoconductor is inorganic.
13. The chipless RFID transponder of claim 1, wherein the
photoconductor comprises an organic polymer.
14. A method of tracking inventory, comprising: placing a chipless
RFID transponder on an article, the RFID transponder comprising, an
antenna and a plurality of resonant structures that together define
a spectral signature of the RFID transponder, each of the resonant
structures comprising conductive portions separated by interstitial
regions; and a reversible photoconductive material disposed in the
interstitial regions of the resonant structures between the
conductive portions, the photoconductive material positioned so as
to shift the spectral signature of the RFID when exposed to
radiation, wherein the photoconductive material has a property of
having a first conductivity prior to being exposed to radiation at
a specified wavelength and a second conductivity that is different
from the first conductivity after being exposed to radiation at the
specified wavelength.
15. The method of claim 14, further comprising detecting a spectral
response of the at least one RFID transponder.
16. The method of claim 15, further comprising determining if the
RFID transponder has been exposed to radiation based on the
detected spectral response.
17. The method of claim 15, wherein the detecting comprises
administering at least one interrogating pulse emitted by an
interrogator, the at least one interrogating pulse comprising a
spectral range.
18. The method of claim 15, wherein the conductive portions of each
resonant structure are formed from a continuous segment of
electrically conductive material that is coplanar with the
interstitial regions.
19. A chipless RFID transponder, comprising: an antenna and a
plurality of resonant structures that together define a spectral
signature of the RFID transponder, each of the resonant structures
comprising conductive portions separated by interstitial regions;
and a reversible photoconductive material disposed in the
interstitial regions of two or more of the resonant structures, the
photoconductive material positioned so as to shift the spectral
signature of the RFID when exposed to radiation, wherein the
photoconductive material has a property of having a first
conductivity prior to being exposed to radiation at a specified
wavelength and a second conductivity that is different from the
first conductivity after being exposed to radiation at the
specified wavelength.
20. The chipless RFID transponder of claim 1, wherein the resonant
structures are spiral resonators.
21. The chipless RFID transponder of claim 1, wherein the
reversible photoconductor material is selected from the group
consisting of selenium, tellurium, selenium tellurium, titanium
dioxide, arsenic triselenide and doped amorphous silicon.
Description
TECHNICAL FIELD
[0001] Embodiments described herein relate generally to
photoconductive chipless radio frequency identification (RFID)
tags.
BACKGROUND
[0002] Radio frequency identification (RFID) technology has gained
tremendous popularity as a device for storing and transmitting
information. RFID technology utilizes a tag transponder, which is
placed on an object, and a reader, also referred to herein as an
interrogator, to read and identify the tag. RFID technologies are
broadly categorized as using either "active" tags or "passive"
tags. Active tags have a local power source (such as a battery) so
that the active tag sends a signal to be read by the interrogator.
Active tags have a longer signal range. "Passive" tags, in
contrast, have no internal power source. Instead, passive tags
derive power from the reader, and the passive tag re-transmits or
transponds information upon receiving the signal from the reader.
Passive tags have a much shorter signal range (typically less than
20 feet).
[0003] Both categories of tags have an electronic circuit that is
typically in the form of an integrated circuit or silicon chip. The
circuit stores and communicates identification data to the reader.
In addition to the chip, the tag includes some form of antenna that
is electrically connected to the chip. Active tags incorporate an
antenna that communicates with the reader from the tag's own power
source. For passive tags, the antenna acts as a transducer to
convert radio frequency (RF) energy originating from the reader to
electrical power. The chip then becomes energized and performs the
communication function with the reader.
[0004] A chipless RFID tag has neither an integrated circuit nor
discrete electronic components, such as the transistor or coil.
This feature allows chipless RFID tags to be printed directly onto
a substrate at lower costs than traditional RFID tags. These
devices, which operate in a "read only" mode are entirely passive
and rely on the resonances created when patterns of specific length
are constructed with conductive materials. The tags are "queried"
with a broadband, polarized microwave pulse and the reirradiated
signal observed in the orthogonal polarization. The power spectrum
of the reirradiated signal show decreases in intensity at those
frequencies corresponding to the conductive resonant structure.
[0005] Optical sensors can be desirable for a variety of
applications. For example, optical sensors can be useful for
transporting or storage of goods, such as determining whether
perishable goods sensitive to radiation are exposed to an
unacceptable amount of radiation during transport or storage. Other
applications include sensing radiation exposure of light sensitive
documents or other light sensitive objects, such as photographic
film.
[0006] Remotely queriable optical sensors most generally rely on
chipped RFID or near field communication (NFC) technologies coupled
with standard optical detection methodologies. This means that,
while effective, such sensors are generally expensive, costing
several dollars to several tens of dollars apiece, thus limiting
the range of applications in which they are used.
[0007] Novel techniques for reducing the cost of optical sensors
would be considered a welcome advancement in the art.
SUMMARY
[0008] An embodiment of the present disclosure is directed to a
chipless RFID transponder. The transponder comprises an antenna and
a plurality of resonant structures that together define a spectral
signature of the RFID transponder. Each of the resonant structures
comprises conductive portions separated by interstitial regions. A
reversible photoconductive material is disposed in the interstitial
regions of the resonant structures between the conductive portions.
The photoconductive material is positioned so as to shift the
spectral signature of the RFID when exposed to radiation.
[0009] Another embodiment of the present disclosure is directed to
a method of tracking inventory. The method comprises placing a
chipless RFID transponder on an article. The RFID transponder
comprises an antenna and a plurality of resonant structures that
together define a spectral signature of the RFID transponder. Each
of the resonant structures comprise conductive portions separated
by interstitial regions. A reversible photoconductive material is
disposed in the interstitial regions of the resonant structures
between the conductive portions. The photoconductive material is
positioned so as to shift the spectral signature of the RFID when
exposed to radiation.
[0010] The optical sensors of the present disclosure can provide
one or more of the following advantages, such as ability to sense
exposure of objects to radiation, the ability to sense exposure to
radiation in real-time, and relatively low cost of manufacture.
[0011] Additional advantages of the embodiments will be set forth
in part in the description which follows, and in part will be
understood from the description, or may be learned by practice of
the embodiments. The advantages will be realized and attained by
means of the elements and combinations particularly pointed out in
the appended claims.
[0012] It is to be understood that both the foregoing general
description and the following detailed description are exemplary
and explanatory only and are not restrictive of the embodiments, as
claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The accompanying drawings, which are incorporated in and
constitute a part of this specification, illustrate embodiments of
the present teachings and together with the description, serve to
explain the principles of the disclosure.
[0014] FIG. 1 depicts a top view of a chipless RFID transponder,
according to an embodiment of the present disclosure.
[0015] FIG. 2A depicts a side view of a chipless RFID transponder
disposed on a carrier, according to an embodiment of the present
disclosure.
[0016] FIG. 2B depicts a side view of the chipless RFID transponder
of FIG. 2A including a photoconductor, according to an embodiment
of the present disclosure.
[0017] FIG. 2C depicts a side view of a chipless RFID transponder
of FIG. 2B including an additional device layer, according to an
embodiment of the present disclosure.
[0018] FIG. 3A depicts a top view of the chipless RFID transponder
of FIG. 2A, according to an embodiment of the present
disclosure.
[0019] FIG. 3B depicts a top view of the chipless RFID transponder
of FIG. 2B, according to an embodiment of the present
disclosure.
[0020] FIG. 4 depicts a schematic view of an interrogator reading a
chipless RFID transponder of the present disclosure.
DESCRIPTION OF THE EMBODIMENTS
[0021] Reference will now be made in detail to the present
embodiments, examples of which are illustrated in the accompanying
drawings. Wherever possible, the same reference numbers will be
used throughout the drawings to refer to the same or like parts. It
will be understood that the structures depicted in the figures may
include additional features not depicted for simplicity, while
depicted structures may be removed or modified.
[0022] Notwithstanding that the numerical ranges and parameters
setting forth the broad scope of the embodiments are
approximations, the numerical values set forth in the specific
examples are reported as precisely as possible. Any numerical
value, however, inherently contains certain errors necessarily
resulting from the standard deviation found in their respective
testing measurements. Moreover, all ranges disclosed herein are to
be understood to encompass any and all sub-ranges subsumed therein.
For example, a range of "less than 10" can include any and all
sub-ranges between (and including) the minimum value of zero and
the maximum value of 10, that is, any and all sub-ranges having a
minimum value of equal to or greater than zero and a maximum value
of equal to or less than 10, e.g., 1 to 5. In certain cases, the
numerical values as stated for the parameter can take on negative
values. In this case, the example value of range stated as "less
that 10" can assume negative values, e.g. -1, -2, -3, -10, -20,
-30, etc.
[0023] The following embodiments are described for illustrative
purposes only with reference to the Figures. Those of skill in the
art will appreciate that the following description is exemplary in
nature, and that various modifications to the parameters set forth
herein could be made without departing from the scope of the
present embodiments. It is intended that the specification and
examples be considered as examples only. The various embodiments
are not necessarily mutually exclusive, as some embodiments can be
combined with one or more other embodiments to form new
embodiments.
[0024] The term "chipless" as used herein to describe RFID
transponders means that the RFID transponder has neither an
integrated circuit nor discrete electronic components, such as a
transistor or coil.
[0025] As used herein, the term "resonant structure" means a
structure having an associated resonance corresponding to a
characteristic frequency.
[0026] As used herein, the term "spectral signature" refers to at
least one identifying resonance associated with an applied
excitation frequency. The spectral signature may have at least one
magnitude component and at least one phase component.
[0027] As used herein, the term "tag" refers to a transponder or a
combination of a transponder and carrier on which the transponder
is disposed.
[0028] As used herein, the term "transponder" refers to a device
that receives signals, such as those transmitted by an
interrogator, and sends signals in response to the received
signals.
[0029] As used herein, the term "etched" refers to a process by
which portions of a material are chemically removed.
[0030] As used herein, the term "security overlayer" means a
backing layer that when tampered with, damages, destroys or
otherwise modifies a structure on which the security overlayer is
disposed.
[0031] As used herein, the term "generic RFID transponder" means an
RFID transponder that has an associated resonant structure for each
frequency domain applied by a transmitter, such as an
interrogator.
[0032] FIG. 1 is a view of a chipless RFID transponder 100. RFID
transponder 100 includes at least one antenna, such as receiving
antenna 102,103 and transmitting antenna 104. Antenna 102 and 103
may be incorporated as part of a circuit that includes a plurality
of resonant structures 104a-104d that, together, define a spectral
signature of the RFID transponder. For example, each of the
plurality of resonant structures 104a-d may exhibit a respective
resonance. The resonance is associated with a natural frequency
that is dependent upon the corresponding resonant structure's
geometry, among other factors. Accordingly, each of the plurality
of resonant structures 104a-d may be used for independent encoding
of a single bit of information. The resonant structure may be a
spiral resonator, such as that shown in FIG. 1, or may be selected
from any other resonant structures that can provide the desired
resonance effect, such as, but not limited to, parallel traces,
meander and fractal shaped resonant structures, all of which are
generally well known in the art. Examples of suitable known
resonant structures are shown in Patent Publication WO 2009/126999,
the disclosure of which publication is herein incorporated by
reference in its entirety.
[0033] The presence of any one resonant structure 104a-104d, each
having a particular resonant frequency, results in a corresponding
attenuation at that frequency in the response of the overall RFID
transponder 100. Accordingly, the presence or absence of each
resonance structure 104a-104d determines the presence or absence of
a corresponding resonance having a particular characteristic
frequency and phase response, which may be used, for example, to
encode one bit of digital information. Each of the plurality of
resonant structures 104a-104d comprise a continuous segment of
electrically connected material having conductive regions 106.
Interstitial regions 107 (FIG. 3A) lie in between portions of the
continuous segment of each resonant structure.
[0034] The chipless RFID transponder 100 includes a reversible
photoconductive material 108 disposed in interstitial regions 107
between the conductive regions 106 (e.g., traces) of the resonant
structures. In an embodiment, at least a portion of the
photoconductive material is disposed in between and coplanar with
the conductive regions 106 of the resonant structure, so that the
entire active resonant structure is formed in the same plane. This
results in the photoconductive materials being interdigitated among
the conductive traces of the resonator structure. This may help
increase the resonance effect of the conductivity changes and can
result in thinner sensors compared to some other resonator
designs.
[0035] The photoconductive material 108 has a property of having
first conductivity prior to being exposed to radiation at a
specified wavelength and a second conductivity that is different
from the first conductivity while being exposed to radiation at the
specified wavelength. The phrase "specified wavelength" can be any
desired wavelength at which the material has been tuned to change
conductivity, and may include any wavelength in the electromagnetic
spectrum, including, for example, wavelengths in the infrared
(e.g., near-, mid- or far-infrared), visible light, and ultra
violet light range. In an embodiment, the second conductivity is
higher than the first conductivity. For example, the
photoconductive material can be an electrical insulator or
semiconductor prior to being exposed to radiation and can become
more electrically conductive, such as a more conductive
semiconductor or an electrically conductive material, when exposed
to radiation at a specified wavelength. In another embodiment, a
photoconductor that exhibits a decrease in conductivity with
exposure to light can be used, so that the second conductivity is
lower than the first conductivity. The photoconductive materials
108 are reversible photoconductors, meaning that they change from
having first conductivity to a second conductivity when exposed to
radiation, but return to the first conductivity after exposure to
the radiation ends. Further, the reversible photoconductors are
capable of repeatedly cycling between the first conductivity and
second conductivity with changing radiation exposure conditions.
The degree in the change of conductivity can be any amount that
will provide a detectable change in resonance when the transponder
is queried.
[0036] The photoconductive material is positioned so as to shift
the spectral signature of the RFID when exposed to radiation. In
particular, the photoconductive material is applied as a filler
between portions of the conductive traces that comprise the
resonant. Suitable photoconductive fillers increase or decrease
conductivity when exposed to radiation. A change in conductivity of
the photoconductor 108 can change the resonance, and thus change
the reflected signal of the transponder when it is queried. For
example, as the conductivity of the filler 108 increases, the
associated attenuation of the reflected power spectrum at the
wavelength of the reflected signal corresponding to the resonator
structure decreases. This effectively allows an increase in
radiation intensity impinging on the photoconductive material to
reduce the resonance of the resonant structures 104a-d. This can in
turn result in a detectable change in the trough associated with
the resonance in the reflected power spectrum, thereby indicating
exposure to radiation.
[0037] Employing technologies well known for the formulation of
photoconductor materials, photoconductor materials can be employed
that exhibit increasing conductivity with increasing incident light
intensity. For example, the change in conductivity with the change
in intensity of the light to which the photoconductive material is
exposed can be substantially linearly dependent. Alternatively,
photoconductors can be used that exhibit a distinct threshold
effect. For example, the value of the second conductivity can
remain substantially the same as the first conductivity unless the
photoconductor is exposed to radiation having a certain threshold
intensity.
[0038] Any suitable type of inorganic or organic photoconductive
materials can be employed. Examples of suitable inorganic
photoconductor materials include chalcogenide based photoconductors
such as selenium, tellurium, selenium tellurium, zinc oxide,
titanium dioxide and arsenic triselenide. Such chalcogenide
materials have advantages including: the ability to be formed into
a homogeneous structure, which allows these photoconductors to
change conductivity isotropically; and ease of deposition, such as
by vacuum deposition. Examples of suitable organic photoconductive
materials include polymeric photoconductive materials such as those
used in the belt structures of modern photo printers and copiers.
The polymeric photoconductors can be multi-layered structures that
include both a charge generating layer and a charge transport
layer. Polymeric photoconductors have certain advantages, such as
the ability to be deposited by relatively inexpensive techniques
and potentially may be useable for sensing a broader range of
radiation wavelengths. Still another example of a generally well
known photoconductor is amorphous silicon, which can include
dopants such as phosphorus, nitrogen containing compounds as well
as various other dopants that are well known in the art. The
addition of various dopants can effectively change the band gap of
the amorphous silicon materials, which can allow for spectral
flexibility in the range of frequency of radiation that can be used
to increase conductivity of the material.
[0039] In an embodiment, the chipless RFID transponder 100 includes
at least one of an optical filter or a converter (a device or
material that absorbs radiation at one wavelength and emits at a
different wavelength) disposed over the plurality of resonant
structures. Photoconductor materials can have a particular spectral
response that limits there use to a particular range of
wavelengths. In other cases, photoconductors can be sensitive to a
relatively broad range of wavelengths and it may be desirable to
have sensitivity to only a particular wavelength in that broader
range. By employing filters or converters interposed between the
light source and the tag, the range of wavelength to which the
transponder is sensitive can be expanded or narrowed as desired.
For example, where a photoconductor material is sensitive only to
light in the visible spectrum and for a given application it is
desired to sense light in the UV, then a converter could be used
that absorbs UV radiation and emits radiation in the visible
spectrum range at which the photoconductor is sensitive. Such a
converter could be used to effectively modify the transponders
range so that it is sensitive to UV radiation. In another example,
a filter can be employed with a photoconductor material having a
broad range of wavelengths in order to effectively narrow the range
of wavelengths to which the transponder is sensitive. Any suitable
type of optical filter or converter can be employed. As an example,
FIG. 2C illustrates a device layer 307 that can represent either an
optical filter material or converter material disposed on the
resonant structures of the transponder.
[0040] The photoconductive material 108 can be disposed in the
interstitial regions of any number of the resonant structures
104a-104d. In an embodiment, the photoconductive material 108 is
disposed in a plurality of the resonant structures, such as two,
three or more of the structures. In an embodiment, photoconductive
material 108 is disposed in all of the resonant structures of the
chipless RFID transponder 100. While the photoconductive material
is active in the interstitial regions of the resonant structures,
for ease of manufacturing it can optionally be deposited in other
regions of the RFID transponder 100 as well, such as over and
around the conductive regions of the resonant structures.
[0041] The chipless RFID transponder 100 does not include an
internal power source. Rather, it is considered a passive device,
deriving its power for transponding information from the
reader.
[0042] As shown in FIGS. 2A and 3A, the transponder 100 may be
disposed on a carrier 301 such as directly on an article or on an
intermediate substrate comprising an optional adhesive backing 302
for attaching onto an article. The carrier 301 may be a substrate
on which the RFID transponder is initially fabricated or may be a
carrier onto which an RFID transponder is transferred after it is
fabricated. A carrier 301 with adhesive backing 302 allows the RFID
transponder to be easily attached (i.e., tagged) onto articles.
[0043] The RFID transponder 100 may be formed by lithography,
etching/stamping or the like. For example, the elements of the RFID
transponder responsible for generating the transponder's spectral
signature may each or independently be formed as etched structures.
RFID transponder 100 may also be a conductive-ink based chipless
RFID transponder, wherein all the components, including at least
one resonant structure, are formed via patterning of films of
conductive material including by printing, such as inkjet printing,
a conductive ink.
[0044] In an embodiment, the antenna 102,103 and conductive
portions 106 of transmitting antenna can be formed by any suitable
technique, such as those discussed above. Then the photoconductive
material 108 can be deposited in the interstitial spaces 107
between the conductive regions 106, as shown in FIGS. 2B and 3B.
Any suitable deposition techniques can be employed. Following
deposition of the photoconductive material 108, additional
components can be included. For example, as mentioned above and as
shown in FIG. 2C, an optical filter or converter 307 can be
deposited. Suitable materials and techniques for forming optical
filters and converters are well known in the art.
[0045] In addition, to prevent unwanted manipulation of the RFID
transponder, a security overlayer 309, as shown in FIG. 2C, may be
placed over the RFID transponder. In an embodiment, the overlayer
309 is non-conductive and abrasion resistant.
[0046] An embodiment of the present disclosure is directed to a
method of tracking inventory. The method comprises placing a
chipless RFID transponder 100 on an article 402, as shown in FIG.
4. Any of the RFID transponders of the present disclosure can be
employed in the method. Thus, the RFID transponder 100 can include
antennas 102,103 and a plurality of resonant structures 104a-d that
together define a spectral signature of the RFID transponder, as
shown in FIG. 1. A photoconductive material 108 is disposed in at
least one of the resonant structures. The photoconductive material
is positioned so as to shift the spectral signature of the RFID
when exposed to radiation.
[0047] The method further comprises detecting a spectral response
of the at least one RFID transponder 100. The detecting includes
employing an interrogator 404 (sometimes referred to herein as a
"reader") to administer at least one interrogating pulse 406, the
at least one interrogating pulse comprising a spectral range that
includes the frequencies over which the resonator structures 104
are tuned. The transponder 100 reflects a signal 408 back to the
reader 404 that can be attenuated depending on the resonance
effects of the resonant structures 104. Based on the detected
spectral response it can be determine whether or not the RFID
transponder has been exposed to radiation.
[0048] The chipless RFID transponders of the present disclosure can
be used in any suitable application that can benefit from an
optical sensing device. For example, the chipless RFID transponders
can be employed for anti-counterfeiting, anti-tampering and other
security purposes, optical data gathering in storage and/or
transport of a variety of goods and/or identification purposes and
can be used with any desired objects, including, for example,
security documents, negotiable instruments such as bank notes,
pharmaceuticals, perishable food items, packaging of items that are
sensitive to radiation, light sensitive paintings or other
products, light sensitive film, inks, and so forth. Moreover, these
devices can be used to maintain a radiation exposure history of
objects by, for example, routinely reading the RFID tags and
collecting and/or storing the gathered data in a memory device.
[0049] While the embodiments have been illustrated with respect to
one or more implementations, alterations and/or modifications can
be made to the illustrated examples without departing from the
spirit and scope of the appended claims. In addition, while a
particular feature of the embodiments may have been disclosed with
respect to only one of several implementations, such feature may be
combined with one or more other features of the other
implementations as may be desired and advantageous for any given or
particular function.
[0050] Furthermore, to the extent that the terms "including",
"includes", "having", "has", "with", or variants thereof are used
in either the detailed description and the claims, such terms are
intended to be inclusive in a manner similar to the term
"comprising." As used herein, the phrase "one or more of", for
example, A, B, and C means any of the following: either A, B, or C
alone; or combinations of two, such as A and B, B and C, and A and
C; or combinations of three A, B and C.
[0051] Other embodiments will be apparent to those skilled in the
art from consideration of the specification and practice of the
descriptions disclosed herein. It is intended that the
specification and examples be considered as exemplary only, with a
true scope and spirit of the embodiments being indicated by the
following claims.
* * * * *