U.S. patent application number 13/217347 was filed with the patent office on 2013-02-28 for object detecting system in imaging-based barcode readers.
This patent application is currently assigned to Symbol Technologies, Inc.. The applicant listed for this patent is Robert W. DiGiovanna, Yuly Mitelman, Igor R. Vinogradov. Invention is credited to Robert W. DiGiovanna, Yuly Mitelman, Igor R. Vinogradov.
Application Number | 20130048850 13/217347 |
Document ID | / |
Family ID | 47557446 |
Filed Date | 2013-02-28 |
United States Patent
Application |
20130048850 |
Kind Code |
A1 |
Vinogradov; Igor R. ; et
al. |
February 28, 2013 |
OBJECT DETECTING SYSTEM IN IMAGING-BASED BARCODE READERS
Abstract
An apparatus for capturing images of a target object having a
barcode. The apparatus includes a reflector, an LED emitting mostly
invisible light, and a photodetector. The LED is configured to emit
a first portion of the invisible light toward the target object
directly and to emit a second portion of the invisible light toward
the reflector. The reflector is configured to redirect at least
some of the second portion of the invisible light toward the target
object. The photodetector is configured to detect returned
invisible light from the target object to generate an electrical
signal.
Inventors: |
Vinogradov; Igor R.;
(Oakdale, NY) ; DiGiovanna; Robert W.; (Shirley,
NY) ; Mitelman; Yuly; (Stony Brook, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Vinogradov; Igor R.
DiGiovanna; Robert W.
Mitelman; Yuly |
Oakdale
Shirley
Stony Brook |
NY
NY
NY |
US
US
US |
|
|
Assignee: |
Symbol Technologies, Inc.
Schaumburg
IL
|
Family ID: |
47557446 |
Appl. No.: |
13/217347 |
Filed: |
August 25, 2011 |
Current U.S.
Class: |
250/271 |
Current CPC
Class: |
G06K 7/10792 20130101;
G06K 7/10732 20130101; G06K 7/10831 20130101 |
Class at
Publication: |
250/271 |
International
Class: |
G06K 7/10 20060101
G06K007/10 |
Claims
1. An apparatus comprising: a housing; an illumination source
within the housing for providing illumination directed toward a
target object; an imaging sensor having an array of photosensitive
elements for capturing an image from the target object; a reflector
within the housing; a light emitting diode (LED) operative to emit
mostly invisible light within an invisible bandwidth, wherein the
LED is configured to emit a first portion of the invisible light
toward the target object directly and to emit a second portion of
the invisible light toward the reflector, and wherein the reflector
is configured to redirect at least some of the second portion of
the invisible light toward the target object; a photodetector
configured to detect returned invisible light from the target
object to generate an electrical signal; and a controller
configured to activate the illumination source for providing the
illumination directed toward the target object for image capturing
only if the electrical signal generated by the photodetector
indicates that the returned invisible light from the target object
is detected.
2. The apparatus of claim 1, wherein the reflector includes a
mirror that is at least partially reflective.
3. The apparatus of claim 1, wherein the reflector includes two
mirrors facing each other with an inclined angle larger than 30
degrees, each mirror is at least partially reflective.
4. The apparatus of claim 1, wherein the reflector includes a
non-flat surface.
5. The apparatus of claim 1, wherein the reflector includes two
non-flat surfaces.
6. The apparatus of claim 1, wherein the reflector includes a
diffusive surface.
7. The apparatus of claim 1, wherein the reflector includes two
diffusive surfaces.
8. The apparatus of claim 1, wherein the reflector includes a
plastic surface.
9. The apparatus of claim 1, wherein the reflector includes two
plastic surfaces.
10. The apparatus of claim 1, wherein the reflector includes a
textured surface.
11. The apparatus of claim 1, wherein the reflector includes a
metal coated surface on a plastic substrate.
12. The apparatus of claim 1, further comprising: a chassis; and
wherein the reflector includes a surface of the chassis.
13. The apparatus of claim 1, further comprising: a filter
positioned in front of the photodetector, the filter being
configured to substantially block light having wavelengths that are
not within the invisible bandwidth of the light emitted by the
LED.
14. A method of operating a barcode reader to decode a barcode on a
target object, the barcode reader includes an object detection
system having a light emitting diode (LED) operative to emit mostly
invisible light within an invisible bandwidth, the method
comprising: activating the LED to emit a first portion of the
invisible light toward the target object directly and to emit a
second portion of the invisible light toward a reflector;
redirecting with the reflector at least some of the second portion
of the invisible light toward the target object; detect returned
invisible light from the target object with a photodetector to
generate an electrical signal; activating an illumination source
for providing illumination directed toward the target object for
image capturing only if the electrical signal generated by the
photodetector indicates that the returned invisible light from the
target object is detected; and capturing an image from the target
object with an imaging sensor having an array of photosensitive
elements.
15. The method of claim 14, wherein said redirecting with the
reflector comprises: redirecting at least some of the second
portion of the invisible light toward the target object with a
mirror that is at least partially reflective.
16. The method of claim 14, wherein said redirecting with the
reflector comprises: redirecting at least some of the second
portion of the invisible light toward the target object with two
mirrors that are at least partially reflective, the two mirrors
facing each other with an inclined angle larger than 30
degrees.
17. The method of claim 14, wherein said redirecting with the
reflector comprises: redirecting at least some of the second
portion of the invisible light toward the target object with a
non-flat surface.
18. The method of claim 14, wherein said redirecting with the
reflector comprises: redirecting at least some of the second
portion of the invisible light toward the target object with two
non-flat surfaces.
19. The method of claim 14, wherein said redirecting with the
reflector comprises: redirecting at least some of the second
portion of the invisible light toward the target object with a
diffusive surface.
20. The method of claim 14, wherein said redirecting with the
reflector comprises: redirecting at least some of the second
portion of the invisible light toward the target object with two
diffusive surfaces.
21. The method of claim 14, wherein said redirecting with the
reflector comprises: redirecting at least some of the second
portion of the invisible light toward the target object with a
plastic surface.
22. The method of claim 14, wherein said redirecting with the
reflector comprises: redirecting at least some of the second
portion of the invisible light toward the target object with two
plastic surfaces.
23. The method of claim 14, wherein said redirecting with the
reflector comprises: redirecting at least some of the second
portion of the invisible light toward the target object with a
surface on a chassis.
24. The method of claim 14, further comprising: reducing unwanted
signals detected by the photodetector caused by unwanted ambient
light, the unwanted ambient light having wavelengths that are not
within the invisible bandwidth of the invisible light emitted by
the LED.
25. An apparatus comprising: an illumination source for providing
illumination directed toward a target object; an imaging sensor
having an array of photosensitive elements for capturing an image
from the target object; a light emitting diode (LED) operative to
emit mostly invisible light within an invisible bandwidth, wherein
the LED is configured to emit a first portion of the invisible
light toward the target object directly and to emit a second
portion of the invisible light toward a reflector; means for
redirecting with the reflector at least some of the second portion
of the invisible light toward the target object; a photodetector
configured to detect returned invisible light from the target
object to generate an electrical signal; and a controller
configured to activate the illumination source for providing the
illumination directed toward the target object for image capturing
only if the electrical signal generated by the photodetector
indicates that the returned invisible light from the target object
is detected.
Description
FIELD OF THE DISCLOSURE
[0001] The present disclosure relates generally to imaging-based
barcode readers.
BACKGROUND
[0002] Various electro-optical systems have been developed for
reading optical indicia, such as barcodes. A barcode is a coded
pattern of graphical indicia comprised of a series of bars and
spaces of varying widths. In a barcode, the bars and spaces having
differing light reflecting characteristics. Some of the barcodes
have a one-dimensional structure in which bars and spaces are
spaced apart in one direction to form a row of patterns. Examples
of one-dimensional barcodes include Uniform Product Code (UPC),
which is typically used in retail store sales. Some of the barcodes
have a two-dimensional structure in which multiple rows of bar and
space patterns are vertically stacked to form a single barcode.
Examples of two-dimensional barcodes include Code 49 and
PDF417.
[0003] Systems that use one or more imaging sensors for reading and
decoding barcodes are typically referred to as imaging-based
barcode readers, imaging scanners, or imaging readers. An imaging
sensor generally includes a plurality of photosensitive elements or
pixels aligned in one or more arrays. Examples of imaging sensors
include charged coupled devices (CCD) or complementary metal oxide
semiconductor (CMOS) imaging chips.
[0004] FIG. 1A and FIG. 1B depict an imaging scanner 50 in
accordance with some embodiments. The imaging scanner 50 has a
window 56 and a housing 58. The imaging scanner 50 is typically a
portable reader that has a base for supporting itself on a flat
surface 30, such as, a countertop. The window 56 generally faces an
operator at the workstation. As shown in FIG. 1A, the operator can
slide or swipe the product 40 past the window 56 from right to
left, or from left to right, in a "swipe" mode, to let an image of
the barcode 40 on the product 42 be captured by the imaging scanner
50. Alternatively, the operator can present the barcode 40 on the
product 42 to the center of the window 56 in a "presentation" mode.
The choice depends on operator preference or on the layout of the
workstation.
SUMMARY
[0005] In one aspect, the invention is directed to an apparatus for
capturing images of a target object having a barcode. The apparatus
includes a housing, an illumination source within the housing for
providing illumination directed toward a target object, and an
imaging sensor having an array of photosensitive elements for
capturing an image from the target object. The apparatus also
includes a reflector within the housing, a light emitting diode
(LED) operative to emit mostly invisible light within an invisible
bandwidth, and a photodetector. The LED is configured to emit a
first portion of the invisible light toward the target object
directly and to emit a second portion of the invisible light toward
the reflector, and wherein the reflector is configured to redirect
at least some of the second portion of the invisible light toward
the target object. The photodetector is configured to detect
returned invisible light from the target object to generate an
electrical signal. A controller in the apparatus is configured to
energize the illumination source for providing the illumination
light for imaging capturing with the imaging sensor toward the
target object only if the electrical signal generated by the
photodetector indicates that the returned invisible light from the
target object is detected.
[0006] The advantages of the present invention will become apparent
to those skilled in the art upon a reading of the following
specification of the invention and a study of the several figures
of the drawings.
BRIEF DESCRIPTION OF THE FIGURES
[0007] The accompanying figures, where like reference numerals
refer to identical or functionally similar elements throughout the
separate views, together with the detailed description below, are
incorporated in and form part of the specification, and serve to
further illustrate embodiments of concepts that include the claimed
invention, and explain various principles and advantages of those
embodiments.
[0008] FIG. 1A and FIG. 1B depict an imaging scanner in accordance
with some embodiments.
[0009] FIG. 2 is a schematic of an imaging scanner in accordance
with some embodiments.
[0010] FIGS. 3A-3B depict an imaging scanner that includes an
object detecting system behind the window of the imaging
scanner.
[0011] FIG. 4 depicts an object detecting system with multiple
virtual light sources in accordance with some embodiments.
[0012] FIGS. 5A-5B and 6A-6B depict an imaging scanner that
includes an improved object detecting system in accordance with
some embodiments.
[0013] The apparatus and method components have been represented
where appropriate by conventional symbols in the drawings, showing
only those specific details that are pertinent to understanding the
embodiments of the present invention so as not to obscure the
disclosure with details that will be readily apparent to those of
ordinary skill in the art having the benefit of the description
herein.
DETAILED DESCRIPTION
[0014] FIG. 2 is a schematic of an imaging scanner 50 in accordance
with some embodiments. The imaging scanner 50 in FIG. 2 includes
the following components: (1) an imaging sensor 62 positioned
behind an imaging lens assembly 60; (2) an illuminating lens
assembly 70 positioned in front of an illumination source 72; (3)
an aiming lens assembly 80 positioned in front of an aiming light
source 82; and (4) a controller 90. In FIG. 2, the imaging lens
assembly 60, the illuminating lens assembly 70, and the aiming lens
assembly 80 are positioned behind the window 56. The imaging sensor
62 is mounted on a printed circuit board 91 in the imaging
scanner.
[0015] The imaging sensor 62 can be a CCD or a CMOS imaging device.
The imaging sensor 62 generally includes multiple pixel elements.
These multiple pixel elements can be formed by a one-dimensional
array of photosensitive elements arranged linearly in a single row.
These multiple pixel elements can also be formed by a
two-dimensional array of photosensitive elements arranged in
mutually orthogonal rows and columns. The imaging sensor 62 is
operative to detect light captured by an imaging lens assembly 60
along an optical path or axis 61 through the window 56. Generally,
the imaging sensor 62 and the imaging lens assembly 60 are designed
to operate together for capturing light scattered or reflected from
a barcode 40 as pixel data over a two-dimensional field of view
(FOV).
[0016] The barcode 40 generally can be located anywhere in a
working range of distances between a close-in working distance
(WD1) and a far-out working distance (WD2). In one specific
implementation, WD1 is in a close proximity to the window 56, and
WD2 is about a couple of feet from the window 56. Some of the
imaging scanners can include a range finding system for measuring
the distance between the barcode 40 and the imaging lens assembly
60. Some of the imaging scanners can include an auto-focus system
to enable a barcode be more clearly imaged with the imaging sensor
62 based on the measured distance of this barcode. In some
implementations of the auto-focus system, the focus length of the
imaging lens assembly 60 is adjusted based on the measured distance
of the barcode. In some other implementations of the auto-focus
system, the distance between the imaging lens assembly 60 and the
imaging sensor 62 is adjusted based on the measured distance of the
barcode.
[0017] In FIG. 2, the illuminating lens assembly 70 and the
illumination source 72 are designed to operate together for
generating an illuminating light towards the barcode 40 during an
illumination time period. The illumination source 72 can include
one or more light emitting diodes (LED). The illumination source 72
can also include a laser or other kind of light sources. The aiming
lens assembly 80 and the aiming light source 82 are designed to
operate together for generating a visible aiming light pattern
towards the barcode 40. Such aiming pattern can be used by the
operator to accurately aim the imaging scanner at the barcode. The
aiming light source 82 can include one or more light emitting
diodes (LED). The aiming light source 82 can also include a laser,
LED, or other kind of light sources.
[0018] In FIG. 2, the controller 90, such as a microprocessor, is
operatively connected to the imaging sensor 62, the illumination
source 72, and the aiming light source 82 for controlling the
operation of these components. The controller 90 can also be used
to control other devices in the imaging scanner. The imaging
scanner 50 includes a memory 94 that can be accessible by the
controller 90 for storing and retrieving data. In many embodiments,
the controller 90 also includes a decoder for decoding one or more
barcodes that are within the field of view (FOV) of the imaging
scanner 50. In some implementations, the barcode 40 can be decoded
by digitally processing a captured image of the barcode with a
microprocessor.
[0019] In operation, in accordance with some embodiments, the
controller 90 sends a command signal to energize the illumination
source 72 for a predetermined illumination time period. The
controller 90 then exposes the imaging sensor 62 to capture an
image of the barcode 40. The captured image of the barcode 40 is
transferred to the controller 90 as pixel data. Such pixel data is
digitally processed by the decoder in the controller 90 to decode
the barcode. The information obtained from decoding the barcode 40
is then stored in the memory 94 or sent to other devices for
further processing.
[0020] The illumination source 72 usually is energized to address
low ambient light conditions and to minimize hand jitter impact or
swiping objects though the FOV on reading performance. On the other
hand having bright illumination of an imaging scanner in constantly
on state is annoying and bothersome for the user. It is also not
efficient from power management perspective. Therefore it is
beneficial to have an object sensing system which energizes
illumination system only if the object of interest is presented
within the predetermined FOV of the imaging scanner 50 and at a
certain distance from the scanner.
[0021] FIGS. 3A-3B depict an imaging scanner 50 that includes an
object detecting system behind the window 56. The object detecting
system in FIG. 3B includes an infrared LED 110 and a photodetector
120. In some existing implementations, the infrared light
projecting out of the window 56 mainly originates from one
particular area--LED chip which may or may not have an auxiliary
lens. These implementations place some limitation on the
effectiveness of the object detecting system. This limitation
becomes apparent in case of reading barcodes from cell phones, a
user application that has recently become very popular. Typically,
cell phone screen is designed in such a way which minimizes
reflected light from its surface. Therefore reflected/scattered
light of the object sensor LED is very low, which is nearly
impossible for detection at larger distances. In general cell
phones have very strong specular reflection from the screen.
Therefore in a particular orientation of the cell phone, the
returned specular reflection signal is quite strong and the object
sensor can be activated at a longer distance. Unfortunately, this
occurs if the cell phone is presented at a particular orientation
only within a limited range of angle.
[0022] The present specification provides an improved object
detecting system where a plurality of virtual light sources are
created from a single source. An advantage of this improved object
detecting system is that multiple specular reflections occur from
cell phone screen, which enables cell phone detection more
effective at longer distances and less dependable on phone screen
orientation.
[0023] FIG. 4 depicts an object detecting system with multiple
virtual light sources in accordance with some embodiments. The
object detecting system includes an infrared LED 110 and a
photodetector 120. The object detecting system also includes two
mirrors 130A and 130B. In some implementations, the two mirrors
130A and 130B are facing each other with an inclined angle larger
than 30 degrees. The mirrors 130A and 130B create virtual light
sources 115A and 115B respectively. Therefore when one looks at the
light source 110, two additional virtual light sources 115A and
115B appear on each side. By these means three light sources (i.e.,
110, 115A, and 115B) have been created. The light sources 110,
115A, and 115B respectively project infrared light 111, 119A, and
119B onto a cell phone screen 49. Each source generates its own
specular reflection from the cell phone screen 49 presented in
front of the object sensor. The signal is detected by the
photodetector 120.
[0024] An optical filter 122 may be used to filter out ambient
light for better signal to noise ratio. It has to be understood
that one, two, three, or more reflective mirrors or surfaces can be
used in this arrangement for generating virtual light sources.
Surfaces may or may not be joined. For example, plastic materials
can have high reflectivity of about 30% at glazing angles of
incident light. If case reflective surfaces have rough finish and
scatter light at certain angle, it may further improve the
possibility of catching specular refection by the
photodetector.
[0025] FIGS. 5A-5B and 6A-6B depict an imaging scanner 50 that
includes an improved object detecting system in accordance with
some embodiments. The imaging scanner 50 includes a housing 58, an
illumination source 72 for providing illumination directed toward a
target object in front of the window 56, and an imaging sensor 62
for capturing an image from the target object. An illuminating lens
assembly 70 is positioned in front of the illumination source 72.
An imaging lens assembly 60 is positioned in front of the imaging
sensor 62. The imaging scanner 50 also includes a mirror 130 in the
housing 58. The mirror 130 is used to reflect the illumination from
the illumination source 72 toward the target object in front of the
window 56 and to reflect returned light from the target object
towards imaging lens 60 and being projected onto the imaging sensor
62.
[0026] As shown in FIG. 5B, the object detecting system of the
imaging scanner 50 includes an LED 110 that emits mostly invisible
light (e.g., infrared light, approximately 800 NM). The LED 110 is
configured to emit a first portion of the invisible light toward
the target object directly and to emit a second portion of the
invisible light toward the mirror 130. Because of the mirror 130, a
virtual light source 115 is generated. The light sources 110 and
115 respectively project invisible light 111 and 119 out of the
window 56. If there is a target object presence in front of the
window 56, some of the invisible light 111 and 119 can be reflected
back into the window 56, and the returned invisible light from the
target object can be detected by a photodetector (which is not
shown in FIG. 5B). Generally, a portion of the invisible light
emitted by the LED 110 can be redirected toward the target object
by a reflector. While the mirror 130 can be used as the reflector,
there are many other possible implementations of the reflector.
[0027] FIGS. 6A-6B depict an implementation of the object detecting
system that includes a reflector for redirecting some invisible
light toward a target object outside the window 56. The imaging
scanner 50 includes the illuminating lens assembly 70 and the
illumination source 72 for providing illumination directed toward a
target object in front of the window 56, after reflecting by the
mirror 130 in FIG. 5A. The imaging scanner 50 also includes the
imaging lens assembly 60 and the imaging sensor 62 for capturing an
image from the target object, after reflecting by the mirror 130 in
FIG. 5A. The imaging scanner 50 has a chassis 150 within the
housing 58.
[0028] The object detecting system of the imaging scanner 50
includes light emitting diodes 110A and 110B that emit mostly
invisible light (e.g., infrared light). The object detecting system
also includes a photodetector 120 configured to detect returned
invisible light from the target object. An optical filter 122 is
positioned in front of the photodetector 120 for increasing the
signal-to-noise ratio and reducing the ambient light. The surfaces
on the side walls of the chassis 150 can be used as a reflector for
redirecting some of the invisible light 119A and 119B from the LEDs
(i.e., 110A and 110B) toward the target object. As shown in FIG.
6A, the invisible light (119A and 119B) from the LEDs (i.e., 110A
and 110B) is reflected from side walls 130A and 130B of the chassis
150. The chassis 150 is made out of plastic material. The plastic
material can be of any color. When the light impinges on a surface,
such as plastic, at a steep angle about 55 degrees, the reflection
of the light could be quite high, about 15-30% depending on the
incident angle and surface finish.
[0029] In some implementations, the side walls 130A and 130B of the
chassis 150 can play similar functions as the mirrors 130A and 130B
in FIG. 4. As such, it appears that the light originates not only
from the LED light source itself (i.e., 110A and 110B) but also
from the chassis walls 130A and 130B. Some of the invisible light
111A and 111B from the LEDs (i.e., 110A and 110B) is emitted
directly toward the target object. Some of the invisible (119A and
119B) light from the LEDs (i.e., 110A and 110B), after redirected
by the chassis walls 130A and 130B, are projected toward the target
object as invisible light 119A and 119B in different directions. If
a cell phone is placed in front of the window 56, these invisible
lights from multiple different directions create multiple
reflections from the cell phone screen, which results in
significantly increased probability to catch a specular reflection
from the cell phone by the detector. Another advantage of this
improved object detecting system is that the light from the LED is
redirected effectively towards the object/barcode and therefore
benefits not only for detection of cell phones but regular paper
barcodes as well.
[0030] In addition to the specific embodiments that have been
described, various modifications and changes are possible. For
example, the mirror for using as the reflector can be highly
reflective or partially reflective. The surface of the reflector
can be substantively diffusive or almost perfectively reflective.
The diffusive surface can be integral part of the scanner housing
or chassis. The surface of the reflector can be made from plastic
or metals. The reflector can have a flat surface or a non-flat
surface or textured. The reflector can have a metal coated surface
on a plastic substrate.
[0031] In the foregoing specification, specific embodiments have
been described. However, one of ordinary skill in the art
appreciates that various modifications and changes can be made
without departing from the scope of the invention as set forth in
the claims below. Accordingly, the specification and figures are to
be regarded in an illustrative rather than a restrictive sense, and
all such modifications are intended to be included within the scope
of present teachings.
[0032] The benefits, advantages, solutions to problems, and any
element(s) that may cause any benefit, advantage, or solution to
occur or become more pronounced are not to be construed as a
critical, required, or essential features or elements of any or all
the claims. The invention is defined solely by the appended claims
including any amendments made during the pendency of this
application and all equivalents of those claims as issued.
[0033] Moreover in this document, relational terms such as first
and second, top and bottom, and the like may be used solely to
distinguish one entity or action from another entity or action
without necessarily requiring or implying any actual such
relationship or order between such entities or actions. The terms
"comprises," "comprising," "has", "having," "includes",
"including," "contains", "containing" or any other variation
thereof, are intended to cover a non-exclusive inclusion, such that
a process, method, article, or apparatus that comprises, has,
includes, contains a list of elements does not include only those
elements but may include other elements not expressly listed or
inherent to such process, method, article, or apparatus. An element
proceeded by "comprises . . . a", "has . . . a", "includes . . .
a", "contains . . . a" does not, without more constraints, preclude
the existence of additional identical elements in the process,
method, article, or apparatus that comprises, has, includes,
contains the element. The terms "a" and "an" are defined as one or
more unless explicitly stated otherwise herein. The terms
"substantially", "essentially", "approximately", "about" or any
other version thereof, are defined as being close to as understood
by one of ordinary skill in the art, and in one non-limiting
embodiment the term is defined to be within 10%, in another
embodiment within 5%, in another embodiment within 1% and in
another embodiment within 0.5%. The term "coupled" as used herein
is defined as connected, although not necessarily directly and not
necessarily mechanically. A device or structure that is
"configured" in a certain way is configured in at least that way,
but may also be configured in ways that are not listed.
[0034] It will be appreciated that some embodiments may be
comprised of one or more generic or specialized processors (or
"processing devices") such as microprocessors, digital signal
processors, customized processors and field programmable gate
arrays (FPGAs) and unique stored program instructions (including
both software and firmware) that control the one or more processors
to implement, in conjunction with certain non-processor circuits,
some, most, or all of the functions of the method and/or apparatus
described herein. Alternatively, some or all functions could be
implemented by a state machine that has no stored program
instructions, or in one or more application specific integrated
circuits (ASICs), in which each function or some combinations of
certain of the functions are implemented as custom logic. Of
course, a combination of the two approaches could be used.
[0035] Moreover, an embodiment can be implemented as a
computer-readable storage medium having computer readable code
stored thereon for programming a computer (e.g., comprising a
processor) to perform a method as described and claimed herein.
Examples of such computer-readable storage mediums include, but are
not limited to, a hard disk, a CD-ROM, an optical storage device, a
magnetic storage device, a ROM (Read Only Memory), a PROM
(Programmable Read Only Memory), an EPROM (Erasable Programmable
Read Only Memory), an EEPROM (Electrically Erasable Programmable
Read Only Memory) and a Flash memory. Further, it is expected that
one of ordinary skill, notwithstanding possibly significant effort
and many design choices motivated by, for example, available time,
current technology, and economic considerations, when guided by the
concepts and principles disclosed herein will be readily capable of
generating such software instructions and programs and ICs with
minimal experimentation.
[0036] The Abstract of the Disclosure is provided to allow the
reader to quickly ascertain the nature of the technical disclosure.
It is submitted with the understanding that it will not be used to
interpret or limit the scope or meaning of the claims. In addition,
in the foregoing Detailed Description, it can be seen that various
features are grouped together in various embodiments for the
purpose of streamlining the disclosure. This method of disclosure
is not to be interpreted as reflecting an intention that the
claimed embodiments require more features than are expressly
recited in each claim. Rather, as the following claims reflect,
inventive subject matter lies in less than all features of a single
disclosed embodiment. Thus the following claims are hereby
incorporated into the Detailed Description, with each claim
standing on its own as a separately claimed subject matter.
* * * * *