U.S. patent application number 12/951348 was filed with the patent office on 2012-05-24 for electro-optical display.
Invention is credited to Brad Benson, Gregg Alan Combs, Tim R. Koch, Pavel Kornilovich, Jeffrey Todd Mabeck, Jong-Souk Yeo.
Application Number | 20120127560 12/951348 |
Document ID | / |
Family ID | 46033234 |
Filed Date | 2012-05-24 |
United States Patent
Application |
20120127560 |
Kind Code |
A1 |
Mabeck; Jeffrey Todd ; et
al. |
May 24, 2012 |
ELECTRO-OPTICAL DISPLAY
Abstract
An electro-optical display includes colorant particles that are
suspended in a carrier fluid. The colorant particles are controlled
by three different types of electrodes. An exposed electrode acts
on the colorant particles in an electrokinetic manner by compacting
the colorant particles. A passivated electrode acts on the colorant
particles in an electrostatic manner by holding the colorant
particles once compacted. A reference electrode attracts the
colorant particles to compaction areas.
Inventors: |
Mabeck; Jeffrey Todd;
(Corvallis, OR) ; Combs; Gregg Alan; (Monmouth,
OR) ; Koch; Tim R.; (Corvallis, OR) ;
Kornilovich; Pavel; (Corvallis, OR) ; Yeo;
Jong-Souk; (Corvallis, OR) ; Benson; Brad;
(Corvallis, OR) |
Family ID: |
46033234 |
Appl. No.: |
12/951348 |
Filed: |
November 22, 2010 |
Current U.S.
Class: |
359/296 |
Current CPC
Class: |
G02B 26/026 20130101;
G02F 1/16762 20190101; G02F 2203/30 20130101; G02F 1/167 20130101;
G02F 1/16756 20190101; G09G 3/3446 20130101; G02F 1/16761 20190101;
G02F 1/133371 20130101 |
Class at
Publication: |
359/296 |
International
Class: |
G02F 1/167 20060101
G02F001/167 |
Claims
1. An electro-optical display comprising: colorant particles
suspended in a carrier fluid; an exposed electrode configured to
compact the colorant particles into collection areas a passivated
electrode configured to hold the colorant particles in the
collection areas; and a reference electrode configured to attract
the colorant particles onto the collection areas.
2. The electro-optical display of claim 1 wherein the
electro-optical display is part of a sub-pixel of an electronic
display.
3. The electro-optical display of claim 1 wherein the passivated
electrode is covered by a dielectric material.
4. The electro-optical display of claim 1 wherein the colorant
particles are comprised of a plurality of different colored
colorant particles having at least one charge polarity.
5. The electro-optical display of claim 1 wherein the passivated
electrode is configured to generate an electric field after a set
amount of the colorant particles are collected in the collection
areas.
6. The electro-optical display of claim 1 and further including a
dielectric material formed on the reference electrode wherein the
dielectric material is patterned to expose areas of the reference
electrode that act as the collection areas.
7. The electro-optical display of claim 1 wherein the exposed
electrode and the passivated electrode are coupled to a first side
of the electro-optical display and are separated either
geometrically or by a dielectric layer and the reference electrode
is coupled to a second side of the electro-optical display that is
opposite the first side.
8. The electro-optical display of claim 1 wherein the exposed
electrode and the passivated electrode comprise transparent
conductive materials and a dielectric on the reference electrode
comprises a reflective material.
9. The electro-optical display of claim 1 and further including: a
first dielectric material coupled to the reference electrode and
patterned to form exposed areas of the reference electrode to act
as the collection areas, wherein the passivated electrode is a
blanket electrode coupled to a first substrate and covered by a
second dielectric material between the passivated electrode and the
carrier fluid; the reference electrode is coupled to a second
substrate opposite the first substrate; and the exposed electrode
is coupled to the first dielectric material between the exposed
areas of the first dielectric material.
10. An electro-optical display comprising: colorant particles
suspended in a carrier fluid; an exposed electrode coupled to a
first substrate and configured to act on the colorant particles in
an electrokinetic manner; a passivated electrode coupled to the
first substrate and configured to act on the colorant particles in
an electrostatic manner; and a reference electrode coupled to a
second substrate and configured to attract the colorant particles
onto collection areas, wherein the second substrate is on an
opposing side of the electro-optical display from the first
substrate.
11. The electro-optical display of claim 10 wherein the reference
electrode is a patterned electrode resulting in a plurality of
reference electrodes that are each a collection area.
12. The electro-optical display of claim 11 and further including a
patterned dielectric material coupled to the second substrate and
having openings for each of the plurality of reference
electrodes.
13. The electro-optical display of claim 10 wherein the passivated
electrode is larger than the exposed electrode.
14. The electro-optical display of claim 10 wherein the passivated
electrode is a blanket electrode coupled to the first substrate and
a dielectric material separates the exposed electrode from the
passivated electrode.
15. The electro-optical display of claim 10 wherein the carrier
fluid is one of: a polar fluid, a non-polar fluid, or an
anisotropic fluid.
16. The electro-optical display of claim 10 wherein the
electro-optical display is part of a pixel of an electronic
display.
17. A method for operating an electro-optical display having a
carrier fluid with charged colorant particles, the method
comprising: biasing a first electrode with a first voltage; biasing
a second electrode with a second voltage such that the charged
colorant particles are moved to the collection areas; and biasing a
third electrode with a third voltage to hold the charged colorant
particles on the collection areas.
18. The method of claim 17 wherein the biasing of the third
electrode with the third voltage occurs only after the first
electrode is no longer biased with the first voltage.
19. The method of claim 18 wherein the electro-optical display is
part of an electronic display of a book reader, a shelf label, a
skin for an electronic device, a sign, a price display, or any
combination thereof.
20. The method of claim 17 wherein the electronic display comprises
a plurality of electro-optical displays as pixels in the display.
Description
BACKGROUND
[0001] Electrophoresis is the translation of charged objects in a
fluid in response to an electric field. Electrophoretic inks are
useful as a medium to enable bistable, low power types of displays.
Electrophoretic displays have been developed using a dyed fluid and
white particles sandwiched between parallel electrodes on top and
bottom substrates. When an electric field is applied transverse to
the substrates across the dyed fluid to translate the white
particles to the viewing surface, the display appears white. When
the electric field is reversed to translate the white particles
away from the viewing surface, the display appears the color of the
dyed fluid. Similarly, electrophoretic displays have also been
developed using a clear fluid with two differently colored
particles of opposite charge (e.g., positively charged white
particles and negatively charged black particles) sandwiched
between parallel electrodes on top and bottom substrates. When the
electrode on the viewing side is charged negatively, the positively
charged white particles are translated to the viewing surface, and
the display appears white. When the electrode on the viewing side
is charged positively, the negatively charged black particles are
translated to the viewing surface, and the display appears black.
Conventional electrophoretic architectures typically use electrodes
that are electrically insulated from the colorant particles and the
carrier fluid such that there is no significant steady state
current flow. The prior embodiments using parallel electrodes to
translate particles transverse to the top and bottom substrates do
not enable a transparent state. When the top surface is color A,
then the bottom surface will appear color B, and vice versa.
[0002] A transparent state can be enabled by "in-plane"
electrophoretic displays, in which electrodes are arranged to apply
electric fields that are substantially parallel to the substrates
to translate colorant particles through a clear fluid parallel to
the substrates. This allows the colorant particles to be collected
out of the viewing area of the display to create a transparent
state. The colorant particles can also be spread across the viewing
area of the display to create a colored state. Since the travel
distances required for in-plane electrophoretic displays are
typically much larger, the switching speeds are typically much
slower. Reducing the travel distance has the undesired effect of
reducing the clear aperture of the viewing area for a given
electrode width. Such an architecture requires electrical
cross-over of in-plane electrodes that increases manufacturing
complexity.
[0003] For the reasons stated above and for other reasons that will
become apparent to those skilled in the art upon reading and
understanding the present specification, there is a need in the art
for alternate ways to control colorant particles in an optical
display.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1 depicts a cross-sectional view of one embodiment of
an electro-optical display.
[0005] FIG. 2 depicts a cross-sectional view of an alternate
embodiment of an electro-optical display.
[0006] FIG. 3 depicts a cross-sectional view of another embodiment
of an electro-optical display.
[0007] FIG. 4 depicts a cross-sectional view of yet another
embodiment of an electro-optical display.
[0008] FIG. 5 depicts a cross-sectional view of yet another
embodiment of an electro-optical display.
[0009] FIG. 6 depicts a top view of one embodiment of an
electro-optical display.
[0010] FIG. 7 depicts a top view of another embodiment of an
electro-optical display.
[0011] FIG. 8 depicts a cross-sectional view of yet another
embodiment of an electro-optical display.
[0012] FIG. 9 depicts a cross-sectional view of yet another
embodiment of an electro-optical display.
[0013] FIG. 10 depicts an electronic display device in accordance
with the electro-optical display of the present disclosure.
[0014] FIG. 11 depicts a magnified view of a portion of an
electro-optical display that can incorporate the present
embodiments.
DETAILED DESCRIPTION
[0015] In the following detailed description of the present
embodiments, reference is made to the accompanying drawings that
form a part hereof, and in which is shown by way of illustration
specific embodiments of the disclosure which may be practiced.
These embodiments are described in sufficient detail to enable
those skilled in the art to practice the subject matter of the
disclosure. It is to be understood that other embodiments may be
utilized and that process, chemical or electrical changes may be
made without departing from the scope of the present disclosure.
The following detailed description is, therefore, not to be taken
in a limiting sense, and the scope of the present disclosure is
defined by the appended claims and equivalents thereof.
[0016] As used herein, the term "grayscale" applies to both black
and white images and monochromatic color images. Grayscale refers
to an image including different shades of a single color produced
by controlling the density of the single color within a given area
of a display. The term "over" is not limited to any particular
orientation and can include above, below, next to, adjacent to,
and/or on. In addition, the term "over" can encompass intervening
components between a first component and a second component where
the first component is "over" the second component. The term
"electro-optical display" is an information display that forms
visible images using one or more of electrophoresis,
electro-convection, electrochemical interactions, and/or other
electrokinetic phenomena. The term "electro-optical display" is
used interchangeably with the terms "electrokinetic display" and
"electrostatic display". Particles moved in an electrokinetic
manner can be moved by one or more of electrophoresis,
electro-convection, and/or electrochemical interactions.
Electrophoresis is the movement of suspended particle through a
medium under the action of an electrostatic force applied using
electrodes. In practice, particles may be moved electrophoretically
or held against a surface by an electrostatic field. The display
elements subsequently described use both out-of-plane movement as
well as in-plane movement of colorant particles to provide the
desired optical appearance.
[0017] The present embodiments encompass optical display elements
that use a hybrid system of electrokinetic switching and
electrostatic holding using three or more electrode types. The
embodiments comprise a reference electrode that is either
geometrically defined or is a blanket conductor with a patterned
dielectric layer. Two types of activating electrodes comprise an
exposed electrode for compacting (i.e., moving) colorant particles
electrokinetically and a passivated electrode for holding colorant
particles electrostatically.
[0018] A passivated electrode is one that is covered by a
dielectric material. The said dielectric material effectively
blocks electrical conductivity between the electrode and the
carrier fluid. Since the passivated electrode is insulated from
contact with the carrier fluid and charged colorant particles, this
electrode interacts with the charged colorant particles by way of
an electric field. The compacting electrode is exposed to the
carrier fluid and the charged colorant particles and, thus, results
in non-negligible steady-state current flow that impacts the motion
of the particles.
[0019] In general, a colorant particle may have a size between
several nanometers and several microns and has the property of
changing the spectral composition of the incident light by
absorbing and/or scattering certain portions of the spectrum. As a
result, the particle appears colored which provides a desired
optical effect. In other embodiments, the colorant can be a dye
that comprises single absorbing molecules.
[0020] The colorant particles in the carrier fluid comprise a
charged material. In one embodiment, the colorant particle is able
to hold a stable charge indefinitely so that repeated operation of
the element does not affect the charge on the colorant particles.
However, colorant particle materials having a finite ability to
hold a stable charge can be used in accordance with the various
embodiments while they maintain their charge.
[0021] The carrier fluid can include both polar fluids (e.g. water)
and non-polar fluids (e.g., dodecane). Additionally, anisotropic
fluids such as liquid crystal can be used. The fluid may include
surfactants such as salts, charging agents, stabilizers, and
dispersants. In one embodiment, the surfactants provide a fluid
that is an electrolyte that is able to sustain current by ionic
mass transport.
[0022] The substrates on which the electrodes of the subsequent
embodiments are formed can be made of plastic, glass, or some other
clear material. Only one of the substrates needs to be clear. The
other substrate can be either clear or an opaque material. The
substrates can be coated with or comprise a reflective material. In
still another embodiment, a light scatterer can be formed on the
subsequently described dielectric material.
[0023] FIG. 1 illustrates a cross-sectional view of one embodiment
of a hybrid electrokinetic and electrostatic display. This
embodiment includes both the holding electrodes 101, 102 and the
compacting electrodes 103, 104 on the same side that is opposite to
the side with the reference blanket electrode 105. In this
embodiment, the holding electrodes 101, 102 perform an
electrostatic holding function and the compacting electrodes 103,
104 perform an electrokinetic switching function.
[0024] This embodiment comprises upper 110 and lower 111
substrates. The holding electrodes 101, 102 and the compacting
electrodes 103, 104 are both formed on one substrate 110 and
separated geometrically. The reference electrode 105 is formed on
the opposing substrate 111. In the illustrated embodiment, the
holding and compacting electrodes 101-104 are formed on the upper
substrate 110 and the reference electrode is formed on the lower
substrate 111. An alternate embodiment can form the holding and
compacting electrodes 101-104 on the lower substrate 111 and the
reference electrode can be formed on the upper substrate 110.
[0025] The reference electrode 105 is a blanket electrode upon
which a dielectric material 107 is formed and patterned. The
patterning of the dielectric material 107 creates the recesses 108
through which portions of the blanket electrode 105 are exposed to
the carrier fluid 124 and colorant particles 123. Through operation
of the display, the colorant particles 123 can be compacted into
the recesses 108 that act as collection areas.
[0026] The holding electrodes 101, 102 are covered by a dielectric
material 120, 121 that insulates these electrodes 101, 102 from the
carrier fluid 124 and the colorant particles 123. The compacting
electrodes 103, 104 remain exposed to the carrier fluid 124 and the
colorant particles 123.
[0027] The dielectric material 107, 120, and 121 can be a
transparent insulating material, an opaque insulating material, or
a reflective insulating material. For example, the upper dielectric
material 120, 121 might be transparent while the lower dielectric
material 107 might be reflective.
[0028] The recesses 108 can be manufactured by many different
processes. These processes include embossing or imprinting with a
master or stamp or etching of the dielectric layer 107. The
recessed regions 108 can be any size and/or shape.
[0029] The depth of the recesses 108 in the dielectric layer 107
can be defined by the following equation:
h m = L L m - L d 1 - P ##EQU00001##
where L is the colorant particle load by volume, L.sub.m is the
maximum closed packed colorant particle load by volume, d is the
thickness of the main element display volume and P is the aperture
ratio defined by 1-A.sub.0/A. The quantity A is the area of the
element display volume while A.sub.0 is the recess area. This
formula for the aperture ratio is true when all the top electrodes
101, 103, and their coatings 120, 121 are transparent.
[0030] In one embodiment, the total area of the defined recess
regions of the blanket electrode 105 is between 1% and 10% of the
area of the display element in order to maximize the optical
contrast between the clear and the dark states. However, the
present embodiments are not limited to any predefined aperture
ratio. For example, an alternate embodiment might have a total area
of the recessed regions being between 10% and 20% of the area of
the display element. Still another embodiment might have a total
area of the recessed regions being between 20% and 50% of the area
of the display element. Other embodiments might have a total area
of the recessed regions being >50% of the area of the display
element for embodiments where low optical contrast is required.
[0031] As an example of operation, the optical display is in a
diffuse or dark state when no power is applied to the display. In
this state, the colorant particles 123 are uniformly dispersed
throughout the viewing area of the display. To clear the display, a
positive voltage (e.g., 30V) is applied to the compacting
electrodes 103, 104 or to all the electrodes 101 to 104, while a
negative voltage is applied to the blanket reference electrode 105.
Thus, the positively charged colorant particles are collected into
the recesses 108 adjacent to the reference electrode 105.
[0032] After the colorant particles 123 are compacted into the
recesses 108, power to the compacting electrodes 103, 104 or to all
the electrodes 101 to 104 is switched to apply predominantly to the
holding electrodes 101, 102. The electric field generated by the
passivated electrodes 101, 102 holds the colorant particles 123 in
the recesses 108 electrostatically.
[0033] FIG. 2 illustrates a cross-sectional view of an alternate
embodiment of an electro-optical display. This embodiment is
similar to the embodiment of FIG. 1 in that the holding electrodes
201, 202 and compaction electrodes 203, 204 are formed on the same
substrate 210 and separated geometrically. A dielectric material
220, 221 is formed over the holding electrodes 201, 202. The
reference electrode 205 is a blanket electrode formed on the
opposing substrate 211 with a patterned dielectric layer 207 formed
on the reference electrode 205.
[0034] The embodiment of FIG. 2 uses holding electrodes 201, 202
that are larger than the compaction electrodes 203, 204. Since the
small amount of current flowing between the compacting electrodes
203, 204 and reference electrode 205 is sufficient to create
effective compaction, the compacting electrodes 203, 204 can have
an overall area that is less than the holding electrodes 201, 202.
The holding electrodes 201, 202 can have a larger area to hold the
colorant particles 223 in place in the recesses 208
electrostatically.
[0035] FIG. 3 illustrates a cross-sectional view of another
alternate embodiment of an electro-optical display. This embodiment
also forms the holding electrodes 301, 302 and compacting
electrodes 303, 304 on the same side and separated geometrically. A
dielectric material 320, 321 is formed over the holding electrodes
301, 302. The reference electrodes are formed on an opposing
substrate 311.
[0036] Instead of a blanket reference electrode, the embodiment of
FIG. 3 includes a patterned reference electrode 330-333 such that
each holding area for the colorant particles comprises a separate
reference electrode 330-333. No dielectric material is necessary on
the reference electrode side of the display for proper operation.
However, if recesses are desired to hold the colorant particles, a
patterned dielectric 306-310 can be formed on the reference
electrode side of the display. The dielectric material 306-310 may
or may not partially overlap the reference electrodes 330-333.
[0037] FIG. 4 illustrates a cross-sectional view of yet another
alternate embodiment of an electro-optical display. This embodiment
also forms both the holding electrode 401 and compacting electrodes
403-405 on one substrate 410. However, this embodiment separates
these electrodes by a dielectric material 430 instead of
geometrically.
[0038] The embodiment of FIG. 4 forms the holding electrode 401 on
the substrate 410 as a blanket electrode. A dielectric material 430
is then formed over the holding electrode 401. The compacting
electrodes 403-405 are formed on the dielectric material 430.
[0039] As in the other embodiments, the reference electrode 420 is
formed on the opposing substrate 411. A patterned dielectric
material 407 is formed over the blanket reference electrode 420 to
form the recesses for the colorant particles. While this embodiment
shows the reference electrode 420 as being a blanket electrode, an
alternate embodiment can use the patterned reference electrode as
illustrated in the embodiment of FIG. 3.
[0040] The blanket holding electrode 401 and dielectric material
430 can be transparent or opaque depending on whether they are
formed on the viewing side of the electro-optical display or the
opposite of the viewing side. In one embodiment, in order to allow
the holding electrostatic field between the holding electrode 401
and the reference electrode 420, the compacting electrodes 403-405
occupy a smaller area while designed to provide compaction of the
colorant particles.
[0041] FIG. 5 illustrates a cross-sectional view of yet another
alternate embodiment of an electro-optical display. This embodiment
forms the compacting electrodes 503-505 and the holding electrode
501 on opposite sides of the electro-optical display.
[0042] In this embodiment, the holding electrode 501 is a blanket
electrode that is formed on the substrate 510. A dielectric
material 530 is formed over the holding electrode 501 to insulate
the holding electrode 501 from the carrier fluid and colorant
particles. The holding electrode 501 and dielectric material 530
are transparent if formed on the viewing side of the display or may
be opaque if formed on the side opposite to the viewing side.
[0043] A reference electrode 520 is formed as a blanket electrode
on the opposite substrate 511. A dielectric layer 507 is formed on
the reference electrode 520 and patterned to form the recesses 508,
509 and expose portions of the reference electrode 520. The
compacting electrodes 503-505 are formed on the dielectric layer
507 between the recesses 508, 509. While this embodiment shows the
reference electrode 520 as being a blanket electrode, an alternate
embodiment can use the patterned reference electrode as illustrated
in the embodiment of FIG. 3.
[0044] FIGS. 6 and 7 illustrate top views of two embodiments of the
layout of the electro-optical displays. These views are looking
through the transparent viewing side of the display. The square
embodiment of FIG. 6 is one embodiment of a metal electrode 403 as
illustrated in FIG. 4. Other configurations, such as hexagonal,
lines, etc. can also be used to build compacting electrodes on top
of the dielectric layer in FIG. 4.
[0045] The hexagonal embodiment of FIG. 7 is one embodiment of a
top view of the structure depicted in FIG. 5 where dots are defined
with patterned dielectric and lines on top of the dielectric that
is defined as a hexagonal shape. The embodiments of FIGS. 6 and 7
are for purposes of illustration only as the present embodiments
are not limited to any one shape.
[0046] FIG. 8 illustrates a cross-sectional view of yet another
alternate embodiment of an electro-optical display. This embodiment
uses a patterned reference electrode 830-833 with a holding
electrode 801 covered by a dielectric 810 on which the exposed
compacting electrodes 803-805 are formed.
[0047] FIG. 9 illustrates a cross-sectional view of yet another
alternate embodiment of an electro-optical display. This embodiment
uses a patterned reference electrode 930-933. A patterned
dielectric 906-910 can be formed on the reference electrode side of
the display. The dielectric material 906-910 may or may not
partially overlap the reference electrodes 930-933. The exposed
compacting electrodes 900-904 are formed on the dielectric material
906-910. The holding electrode 940 is a blanket electrode covered
by a dielectric material 950.
[0048] The above-described embodiments can not only be used to
create transparent and dark display modes but also multiple
grayscale states. As discussed previously, when the colorant
particles are spread out throughout the carrier fluid, the display
assumes the color of the colorant particle. When the colorant
particles are compacted into the recesses, the display is light.
When some of the colorant particles are compacted and some are
spread out, various levels of gray of that color can be
achieved.
[0049] The different levels of gray can be achieved by controlling
the amount of colorant particles that are spread out in the viewing
area of the display element. Amplitude and pulse width modulation
can be used during the compaction operation (i.e., electrokinetic
switching phase) with the compaction electrode to produce the
grayscale states between the colored state and the light state. As
an example of pulse width modulation, by controlling the amount of
time that the compaction electrodes are turned on, the amount of
colorant particles that are compacted is controlled. Thus, the
longer the positive voltage pulse applied to the compaction
electrodes, the lighter the display becomes. The holding electrodes
can then be used to maintain the selected grayscale state during
the electrostatic holding phase.
[0050] In the above-described embodiments, the polarities discussed
for the operational voltages assume that the colorant particles are
positively charged. In an embodiment where the colorant particles
are negatively charged, the polarities of the operational voltages
will be reversed.
[0051] FIG. 10 is an electronic display device 1000 that uses the
presently disclosed electro-optical display. The electronic display
device 1000 can have a case 1002 that may be made from plastic,
metal, or other material. The electronic display device can be an
electronic book reader, a shelf tag, a skin (surface display) for
an electronic device, a sign, a price display or other display, or
any combinations thereof. The case 1002 can include a number of
buttons 1004 to control the electronic display device 1000, for
example, selecting a publication, turning a page, or opening a
connection to a server. The display cells can have multiple states
that allow the display 1006 to display high-contrast text 1008 and
images 1010. A magnified view 1012 of a portion of the display 1006
is shown in FIG. 11.
[0052] FIG. 11 is a magnified view 1012 of a portion of the display
1006 of FIG. 10. In the magnified view 1012, individual pixels 1102
are shown. Each pixel 1102 can include one or more electro-optical
display cells that may act as sub-pixels to allow the pixel 1102 to
display different colors. Although the pixels 1102 are shown as
hexagons, they may be any appropriate shape, including squares,
circles, and the like. The pixels 1102 may be a shape that allows
tessellation of pixels 1102, such as a square, rectangle, triangle,
or hexagon (as shown). As an example, multiple states of the pixels
1102 are shown in the magnified view 1012, in which a first group
of the pixels 1104 are displaying a color, a second group of the
pixels 1106 are displaying white, and a third group of the pixels
1108 are displaying black.
[0053] Although specific embodiments have been illustrated and
described herein it is manifestly intended that the scope of the
claimed subject matter be limited only by the following claims and
equivalents thereof.
* * * * *