U.S. patent application number 10/722672 was filed with the patent office on 2005-08-18 for electronic assembly/system with reduced cost, mass, and volume and increased efficiency and power density.
Invention is credited to Popovich, John M..
Application Number | 20050180136 10/722672 |
Document ID | / |
Family ID | 32659032 |
Filed Date | 2005-08-18 |
United States Patent
Application |
20050180136 |
Kind Code |
A9 |
Popovich, John M. |
August 18, 2005 |
Electronic assembly/system with reduced cost, mass, and volume and
increased efficiency and power density
Abstract
An LED display assembly, comprising a grid of electrical
conductors; light emitting diodes in association with the grid and
in electrical communication with the conductors that provide power
for LED operation, the grid operable to receive heat from the
diodes during diode operation, and the array configured for passing
coolant fluid for transfer of heat to the fluid. LED packages
adjustable relative to a mounting grid, are also provided.
Inventors: |
Popovich, John M.; (Solana
Beach, CA) |
Correspondence
Address: |
William W. Haefliger
Suite 512
201 So. Lake Ave.
Pasadena
CA
91101
US
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Prior
Publication: |
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Document Identifier |
Publication Date |
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US 0018424 A1 |
January 27, 2005 |
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Family ID: |
32659032 |
Appl. No.: |
10/722672 |
Filed: |
November 28, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10722672 |
Nov 28, 2003 |
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10625185 |
Jul 23, 2003 |
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60405826 |
Aug 26, 2002 |
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Current U.S.
Class: |
362/247 |
Current CPC
Class: |
H01L 2224/48091
20130101; H01L 2224/45124 20130101; H01L 2224/48091 20130101; D03D
1/0088 20130101; D10B 2401/18 20130101; H01L 2924/00014 20130101;
H01L 2224/45124 20130101; H01L 2924/00 20130101; G09F 9/33
20130101 |
Class at
Publication: |
362/247 |
International
Class: |
F21V 007/00 |
Claims
I claim:
1. The method of providing an LED array assembly, that includes: a)
providing a grid of electrical conductors, b) providing light
emitting diodes and locating the diodes in association with the
grid and in electrical communication with the conductors that
provide power for LED operation, c) the grid operable to receive
heat from the diodes during diode operation, and the grid
configured for passing coolant fluid for transfer of heat to the
fluid.
2. The method of claim 1 wherein the electrical conductors are
provided in the form of insulated metal wires that act as
electrical and thermal conductors and that also serve as structural
load conductors, for arrays of such diodes.
3. The method of claim 1 wherein the wires are dielectrically
coated.
4. The method of claim 1 wherein the conductors are provided in the
form of woven wires.
5. The method of claim 1 wherein the array has at least one of the
following characteristics: i) curvature ii) complex shape iii)
compliant configuration iv) flexibility.
6. The method of claim 1 including effecting and/or guiding flow of
coolant fluid through or along the array.
7. The method of claim 1 wherein the grid is provided as a dark
grid to increase viewing contrast with LEDs during their
operation.
8. The method of claim 1 including providing one of the following:
i) a substrate above which LEDs are placed ii) a superstrate
associated with the array and LEDs to provide structural strength
to the assembly.
9. The method of claim 1 including providing a first sheet facing
the diodes, to pass light emitted by the diodes.
10. The method of claim 9 including providing a second sheet at an
opposite side of the diodes, the first and second sheets forming an
enclosure within which coolant fluid is flowable.
11. The method of claim 1 wherein the grid of electrical conductors
is provided to include primary conductors extending generally in
one direction, and secondary conductors extending generally in
another direction, the LEDs being mounted on the primary
conductors, and having terminals extending to the secondary
conductors for electrical association thereto.
12. The method of claim 11 wherein the secondary conductors are
configured to extend above and/or below the primary conductors.
13. The method of claim 12 wherein the secondary conductors are
provided to have one of the following: i) substantial spacing
therebetween to pass coolant fluid through the grid, ii) lack of
substantial spacing therebetween, to pass coolant fluid parallel to
the grid, iii) cross sections which are substantially less than the
cross sections of primary conductors which support diodes, iv)
junctions with diode wires.
14. The method of claim 1 wherein certain of the conductors include
multiple wire strands.
15. The method of claim 1 including providing balls or beads and
seating the balls or beads on the conductors to act as spacers.
16. The method of claim 1 including providing means displacing and
conducting coolant to one side of the screen, to flow through or
adjacent to the array assembly.
17. The method of claim 1 including providing a transparent panel
extending in the path of light from the LEDs.
18. The method of claim 1 wherein each diode is provided to include
a light emitter or emitters, a transparent container having a
window area, the emitter supported within the container, and a
reflector within the container to reflect emitted light toward said
window.
19. The method of claim 18 including providing an electrical lead
or leads extending with helical configuration within the container
to said emitter or emitters.
20. The method of claim 19 wherein the lead or leads is or are
formed to has or have a generally rectangular cross section, for
stable support of the emitter or emitters.
21. The method of claim 18 including providing a metallic base
carrying the container, and through which said lead or leads
extend.
22. The method of claim 20 including providing said lead or leads
include wires associated with a red and/or green and/or blue
emitter.
23. The method of claim 18 wherein multiple of said diodes have
their container windows facing in the same or selected
directions.
24. The method of claim 23 wherein the diodes and array assembly
define a display.
25. The method of claim 21 wherein said base is provided to have an
edge portion defining a recess for reception of a support for the
diode, allowing diode rotation about the support, and including
effecting said rotation.
26. The method of claim 25 wherein said electrical conductors are
provided to define a mesh, and multiple of said LED devices are
carried by the mesh, with said recesses receiving portions of said
conductors allowing rotation of the devices relative to the
mesh.
27. The method of providing a light emitting diode device, that
includes i) providing an electrically energizable light emitter, or
emitters; ii) providing a transparent container having a window;
iii) supporting the emitter or emitters within the container; iv)
and providing a reflector structure within the container to reflect
emitted light toward said window.
28. The method of claim 27 including providing an electrical lead
or leads extending with helical configuration within the container
to said emitter or emitters.
29. The method of claim 27 wherein the lead or leads is or are
provided to has or have a generally rectangular cross section, and
to support the emitter or emitters.
30. The method of claim 27 including providing a metallic base
carrying the container, and through which said lead or leads
extend.
31. The method of claim 27 wherein said reflector structure is
provided to include spaced reflecting walls, and a curved reflector
supported between said walls.
32. The method of claim 28 including providing said lead or leads
to include wires associated with a red and/or green and/or blue
emitter.
33. The method of claim 27 including providing multiple of said
devices having their windows facing in a display direction or
directions.
34. The method of claim 33 including providing display structure
supporting said diode devices in a multiple diode display
configuration.
35. The method of claim 30 wherein said base has is provided to
have an edge portion defining a recess for reception of a support
for the diode, allowing diode rotation about the support, and
including effecting said rotation to a selected diode display
configuration.
36. The method of claim 1 wherein certain of said conductors that
provide power for diode operation are configured as first, second
and third pairs of wires to transmit electrical energization to
red, green and blue LED pixels, respectively.
37. The method of claim 36 wherein each LED has primary, secondary
and tertiary wires electrically connected to the red, green and
blue pixels, respectively, said primary wire configured to be clamp
connected to said first pair of wires, said secondary wire
configured to be clamp connected to said second pair of wires, and
said tertiary wire configured to be clamp connected to said third
pair of wires.
38. The method of claim 37 including locating said three pairs of
wires about a central region, and said LED primary, secondary and
tertiary wires are respectively nested between said three pairs of
wires, there being a retainer acting to clamp said primary,
secondary and tertiary wires in nested position.
39. The method of claim 38 wherein said certain conductors are
located to extend at an acute angle or angles relative to others of
said conductors, said certain conductors defining LED addressing
conductors to selectively address LEDs on said others of the
conductors.
40. The method of claim 39 wherein said acute angle or angles are
approximately 450.
41. The method of claim 1 including providing protective means at
one of the following: i) at the front of the grid; ii) at the rear
of the grid; iii) at both the front and rear of the grid.
42. The method of claim 1 wherein said protective means is provided
to include at least one metallic plate.
43. The method of claim 42 wherein said metallic plate is
characterized by one of the following: X.sub.1) forming air passing
openings; X.sub.2) forming air passing louvers; X.sub.3) forming
air passing through slits.
44. The method of claim 42 wherein said protective means is
provided in the form of a metallic screen or screens.
45. The method of claim 1 wherein the diodes are removably
supported by the grid.
46. The method of claim 1 characterized by at least one of the
following: i) diode emission control electronics provided within
diode packages ii) diode emission control electronics provided at
or proximate an edge or edges of the grid.
47. The method of claim 1 including providing a light reflecting
mirror or mirrors in association with a diode or diodes.
48. The method of claim 47 wherein said mirror or mirrors is or are
provided in the form of one or more of the following: i) a
parabolic mirror ii) dual mirrors within a package iii) a parabolic
trough forming mirror or mirrors.
49. The method of claim 1 including providing a conduit for
extensions of the conductors, outside the grid.
50. The method of claim 49 including providing spring tension
exerting means acting on the conduit.
51. The method of claim 49 including providing holders about which
end portions of the conductors in the grid are looped, the holders
provided in association with the conduit.
52. The method of claim 1 wherein the diodes are provided in the
form of packages having adjustable operative connection to the
conductors characterized by one of the following: i) rotatable
adjustability about one axis ii) rotatable adjustability about two
axes.
53. The method of claim 52 wherein the diodes packages in the array
are provided to have different positions of adjusted
angularity.
54. The method of providing and LED array assembly that includes:
a) providing a grid of electrical conductors, b) providing light
emitting diodes and locating the diodes in association with the
grid and in electrical communication with the conductors that
provide power for LED operation, c) and providing LED structure
allowing rotary adjustment of at least some LEDs relative to
conductors on which those LEDs are supported.
55. The method of claim 54 wherein said rotary adjustment is
characterized by one of the following: i) rotation about an axis or
axes defined by the LED or LEDs ii) rotation about a conductor axis
or axes iii) rotation about both i) and ii) above.
56. The method of claim 54 including providing clip means
positioning the conductors relative to which the LEDs are rotatably
adjustable.
57. The method that includes: a) providing multiple LEDs in a
display array, and b) selectively electrically energizing the LEDs
in the array to adjust the display, c) cooling the display
array.
58. The of claim 57 including selectively adjusting the positioning
of the LEDs in the array.
Description
BACKGROUND OF THE INVENTION
[0001] This application is a continuation-in-part of prior pending
U.S. application Ser. No. 10/625,185 filed Jul. 23, 2003.
[0002] The methods described and claimed herein relate generally to
provision of electronic-optical packages, and more particularly to
provision of grids or arrays of such packages supported in such
manner as to facilitate their installation and use as in closely
assembled or packed configurations.
[0003] Large-scale LED displays are typified by the use of T 13/4
(5 mm) packaged LEDs soldered to rigid printed circuit boards. Such
circuit board/modules typically contain a large number of LEDs and
must be replaced to correct for the failure of even a single LED.
In addition to cost, weight and volume issues or problems, these
displays are limited in resolution as a result of the LED package
size (typically 0.2 inches in diameter), or about 300 times the
plan form area of a bare LED (8000 times the volume), and they are
limited in brightness by the small number of LEDs that can be
placed in a given area, and also by the thermal resistance of the
package and module design. The resolution limit is a function of
spacing that is further restricted by package (LED) size. The
brightness limit is a function of the number of LEDs per unit area
and their individual light output, which is further dependent on
the thermal resistance between the LED junction and the local
environment. Also, existing LED signage and displays have limited
ability to tailor the radiation emission pattern to the needs of
the target/audience and thereby increase efficiency. Increased
efficiency allows for reduced system and operating cost and/or more
radiation delivered to the target.
[0004] There is need for improvements in the provision and
operation of LED display assemblies that overcome problems of
heating and inability to adequately transfer or dispose of heat
generated by LED operation; problems of inadequate LED support on
substrates or circuit boards; problems resulting from lack of
flexibility of the LED support means; difficulties in manufacturing
close packed LED displays; and other problems and difficulties as
will appear.
SUMMARY OF THE INVENTION
[0005] It is a major object of the methods disclosed herein to
provide ways for overcoming the above identified problems.
Basically, the improved method includes:
[0006] a) forming an array, or grid of electrical conductors,
[0007] b) providing light emitting diodes located in association
with the array and in electrical communication with the conductors
that provide power for LED operation,
[0008] c) the array operable or operated to receive heat from the
diodes during diode operation, and the array or grid configured for
passing coolant fluid for transfer of heat to the fluid.
[0009] As will appear, the electrical conductors typically and
advantageously may be provided in the form of insulated metallic
wires which may be interwoven or configured to act as electrical
and thermal conductors, and that also may serve as structural
supports for arrays of LEDs. The LEDs may be selectively removed or
replaced on such supports.
[0010] Another aspect of the improved method includes provision of
an LED supporting means, such as a grid characterized by ease of
conformance to selected shape, curvature, or complex configuration
after the LED array is attached to the grid, the grid having
flexibility to enable such compliance to desired shaping.
[0011] Another object is to effect and/or guide flow of coolant
fluid through or along a shape compliant screen incorporating such
LEDs. In this regard, the screen is amenable to fitting to
[0012] i) a substrate on which LED bases are placed, and/or
[0013] ii) a superstrate provided in association with the screen
and LEDs, to provide structural strength to the assembly.
[0014] Yet another aspect of the improved is to provide a first
protective sheet facing the diodes to pass light emitted by the
diode array; and to provide a second sheet at the opposite side of
the screen and diodes, the first and second sheets forming an
enclosure within which coolant fluid is flowable. The screen itself
may be dark or darkened to increase viewing contrast with the LED
array, during its operation.
[0015] A further feature is provision of the electrical conductors
to include primary conductors extending generally in one direction,
and secondary conductors extending generally in another direction,
the LEDs mounted on the primary conductors, and having terminals
extending to the secondary conductors for electrical association
thereto. In this regard, secondary conductors are typically
provided to have one of the following:
[0016] i) substantial spacing therebetween to pass coolant fluid
through the screen,
[0017] ii) reduced spacing therebetween, to pass coolant fluid
primarily parallel to the screen,
[0018] iii) cross sections which are substantially less than the
cross sections of primary conductors which support diodes,
[0019] iv) junctions with diode wires.
[0020] Yet another feature is provision of a screen display
incorporating diodes or diode devices, wherein each diode is
provided to include a light emitter or emitters, a transparent
container having a window area, the emitter supported within the
container, and a reflector within the container to reflect emitted
light toward said window. As will appear, an electrical lead or
leads may be provided to extend with helical configuration within
the container, such as a glass tube, to the emitter or emitters.
The lead or leads may be formed to have flattened, or generally
rectangular cross sections for stable support of the emitter or
emitters.
[0021] The improved may include provision of a metallic base
carrying the container, and through which said lead or leads
extend. The base typically is formed to have an edge portion
defining a recess for reception of a support for the diode,
allowing diode rotation about the support. Multiple of the diodes
may be supported by a conductor or conductors in a screen, and to
have their windows oriented to face in the same or selected
directions. The diodes may be rotated, or be rotatable, about axes
defined by their supporting conductors.
[0022] Additional features include provision of certain power
providing conductors that comprise first, second, and third pairs
of wires to transmit electrical energization to red, green and blue
LED pixels, respectively; provision of LED primary, secondary and
tertiary wires electrically connected to the red, green and blue
pixels, respectively, said primary wires clamp connected to said
first pair of wires, said secondary wires clamp connected to said
second pair of wires, and said tertiary wires clamp connected to
said third pair of wires; provision for clamped nesting of such
primary, secondary and tertiary wires; provision of certain
conductors that extend at an acute angle or angles relative to
others of said conductors; provision of protector means such as a
plate or plate, or a screen or screens at the front or rear of the
grid, and with air passing openings, as will appear.
[0023] The method as disclosed also includes:
[0024] a) providing multiple LEDs in a display array, and
[0025] b) selectively electrically energizing the LEDs in the array
to adjust the display,
[0026] c) cooling the display array.
[0027] A further aspect of the includes selectively adjusting the
positioning of the LEDs in the array to controllably vary the
overall display.
[0028] These and other objects and advantages of the invention, as
well as the details of an illustrative embodiment, will be more
fully understood from the following specification and drawings, in
which:
DRAWING DESCRIPTION
[0029] FIG. 1 is a perspective view showing provision of one form
of grid or screen incorporating LEDs, and FIG. 1a is similar but
shows coolant flow through the screen;
[0030] FIG. 2 is a perspective view showing provision of another
form of grid or screen incorporating LEDs, and showing coolant flow
primarily adjacent and across the screen and diodes;
[0031] FIG. 3 is a view like FIG. 2 but showing coolant flow
primarily through the screen and past diodes;
[0032] FIG. 4 is a top plan view of an array of diodes on a screen
similar to that of FIG. 1, and showing open spaces between
conductors to pass coolant fluids;
[0033] FIG. 5 is a top plan view of an array of diodes on a screen,
similar to that of FIG. 2, the conductors provided in closely
packed relation;
[0034] FIG. 6 is a view like that of FIG. 5, but showing a
different configuring of electrical conductors;
[0035] FIGS. 7 and 8 are perspective views of two different forms
of LEDs as provided;
[0036] FIGS. 9-12 are perspective views of sections of electrical
conductors as provided;
[0037] FIG. 13 shows weaving of electrical conductors;
[0038] FIG. 14 is an edge view taken on lines 14-14 of FIG. 13;
[0039] FIG. 15 is a perspective view of a ball grid connection to a
screen;
[0040] FIG. 16 is a plan view of a ball grid connection to a
screen;
[0041] FIG. 17 is an elevation showing a ball grid connection to a
screen;
[0042] FIG. 18 is a perspective view showing yet another screen
configuration;
[0043] FIG. 19 is an edge view of the screen of FIG. 18; and
[0044] FIGS. 20-23 show arrangements of electrical conductors
forming screens, and arrays of LEDs mounted thereon;
[0045] FIG. 24 is a view showing screen cooling;
[0046] FIG. 25 is a section taken through an LED package as
provided;
[0047] FIG. 26 is a section taken on lines 26-26 of FIG. 25;
[0048] FIG. 27 is a view showing a display provided to embody
multiple LED packages of the type shown in FIGS. 25 and 26;
[0049] FIG. 28 is a view showing a display provided to embody
multiple LED packages as shown in FIGS. 25 and 26, the packages
mounted on a conductor screen of the type shown in FIG. 1; and FIG.
28a is a modification;
[0050] FIG. 29 shows an LED package mounted on a screen conductor
and transmitting light to a reflector;
[0051] FIG. 30 is a schematic diagram of a sign that incorporates
the LED supporting grid, and with address wires provided to extend
at acute angles;
[0052] FIG. 31 is a perspective view of a wire bundle as
provided;
[0053] FIG. 32 is a cross section taken through the FIG. 31 wire
bundle;
[0054] FIG. 33 is a section taken on lines 33-33 of FIG. 32;
[0055] FIG. 34 is a view of protective metallic plate, with air
passing openings;
[0056] FIG. 35 is a section taken through a grid as described, with
protective mesh at front and rear sides thereof;
[0057] FIG. 36 is a view like FIG. 35, showing use of air passing
louvers;
[0058] FIG. 37 is a plan view showing multiple light emitter
packages supported by wires, in an array;
[0059] FIG. 38 is an enlarged view of a portion of the FIG. 37
array;
[0060] FIG. 39 is a view of two light emitter packages in FIG. 38,
but in rotated positions;
[0061] FIG. 40 is an end view of a connector as shown in FIGS. 38
and 39;
[0062] FIG. 41 is an end view of a conductor conduit supporting
conductor wire terminal holders;
[0063] FIG. 42 is a top plan view taken on lines 42-42 of FIG.
41;
[0064] FIG. 43 is a perspective view of a conductor wire channel,
as also seen in FIG. 41;
[0065] FIG. 44 is a view showing retraction of conductor wires;
[0066] FIG. 45 is an enlarged and rotated view of FIG. 42;
[0067] FIG. 46 is a front elevation showing locations of pixel
packages on a fragmentary grid of addressing wires arrayed at
45.degree. relative to conductor wires;
[0068] FIG. 47 is an enlarged view, like FIG. 44, but taken at the
opposite end of the grid;
[0069] FIG. 48 is a schematic perspective view showing pixel
package adjustment rotation about the package axes;
[0070] FIG. 49 is a schematic perspective view showing pixel
package with adjustment rotation capacity about the axis of the
package supporting conductor;
[0071] FIG. 50 shows in schematic form a representative grid having
supporting wires or conductors, and pixel packages adjusted at
different angles, as for use in a billboard;
[0072] FIG. 51 is a schematic view showing pixel packages on a
grid, and with control electronic circuitry integrated into the
packages;
[0073] FIG. 52 is a schematic view like FIG. 51, with control
circuitry in zones or modules at edges of the grid;
[0074] FIG. 53 is a fragmentary view showing wire conduit wire
conduit tensioning;
[0075] FIG. 54 is a schematic view showing use of bowed end wall
mirrors in a pixel package;
[0076] FIG. 55 is a view like FIG. 54, but rotated 90.degree. about
the package axis.
DETAILED DESCRIPTION
[0077] FIG. 1 shows a screen 10 forming a grid of electrical
conductors. As illustrated, the conductors include like primary
conductors 11 extending generally in one direction, and designated
as an X-direction; and secondary conductors 12 extending generally
in another direction, designated as a Y-direction. As shown, the
primary conductors preferably have overall diameters d.sub.1 or
cross sections greater than the overall diameters d.sub.2 or cross
sections of the secondary conductors, and the latter extend over
and under the conductor 11 in a weaving or mesh relationship as at
12a and 12a'. There is space as at 15 between successive parallel
conductors 11; and there is space as at 16 between successive
undulating conductors 12, whereby coolant can flow downwardly
through the screen via spaces 15 and 16 and near or adjacent
diodes, to remove heat generated by diode operation.
[0078] Light emitting diodes are located or mounted in an array on
various conductors, as shown on crests of conductor 12, and in such
manner that each diode is in electrical communication with two
conductors, establishing a circuit path from a conductor 11 to a
conductor 12, via the diode internal circuit. See conductor
energization controls 20 and 21 for two representation diodes 22
and 23, with circuit paths (for diode 22) at 24, 11a, 22, 25,
junction 26, 12a, 12b and 27; and circuit paths (for diode 23) at
28, 11b, 23, 29, junction 30, 12a, 12b, and 29. Controls 20 and 29
are interconnected so that diodes 22 and 23 can be selectively
energized in timed relation. Diode 22 is mounted on the top side or
crest of conductor 11a, and diode 23 is mounted on the top side of
conductor 1b. Other diodes as shown are similarly mounted and
selectively controlled by controls indicated in bank 31, controls
20 and 21 considered as part of that bank. Electrical connections
to metallic wires in the conductors are made by removal of or
penetration through conductor insulation. Wires 25 and 29 extend in
the Y-direction, and may be insulated. Junctions as at 26 and 30
are provided on all crests of secondary conductors 12, and all LEDs
are mounted on conductors 11, and protectively between sequential
crests of conductors 12.
[0079] The electrical conductors may comprise insulated metal wires
that act as electrical and thermal conductors and that also serve
as structural load conductors, for arrays of such diodes. See for
example FIG. 9 showing metallic conductor 40 having a square cross
section, and a layer 41 of dielectric insulation thereon; FIG. 10
showing metallic conductor 42 having tubular cross section with
bore 42a, and a cylindrical layer 43 of insulation thereon; FIG. 11
showing circular cross section metallic wire at 44, tubular
insulation layer 45, tubular cross section metallic wire 46, and
tubular layer of insulation 47; and FIG. 12 showing solid metallic
wire 48 and insulation 49 thereon, 48 being circular and 49 being
tubular. FIG. 7 shows a six-sided LED body 80 with electrical
terminal areas 81 and 82; and FIG. 8 shows a similar LED body with
terminal areas 83 and 84.
[0080] FIG. 1a is like FIG. 1, showing an array of LEDs 23 and 24
staggered in the Y-direction at one side of the screen defined by
the interwoven conductors 11 and 12. Coolant such as air flows at
54, downwardly toward and over the diodes and through the screen
defined by spaced conductors 11 and 12. Air may also be caused to
flow generally parallel to the screen, as in the X or Y direction,
to cool the screen and diodes. Heat generated by the diodes is
carried away by coolant flow. Note diode wire junctions 60 with and
at the tops of the supporting conductors 12, maximally exposed to
coolant flow for heat transfer to coolant. The conductors 11 are
large enough in diameter to support the mounted and exposed diodes
22 and 23 and other similar diodes, arrayed as shown.
[0081] In FIGS. 2 and 5, the conductors 11 are generally the same
as the conductors 11 in FIG. 1, and are spaced apart as seen at 60.
The conductors 12 are arranged in side by side pairs, as seen for
example at 12' and 12', and 12" and 12". Successive pairs of such
conductors pass over and under conductors 11, as shown. Like pairs
12' pass together over a conductor 11, along its length, and like
successive pairs 12" pass together over the next conductor 11,
along its length in staggered relation in the X-direction in
relation to closest pairs 12'; and portions of the pairs 12" nest
between portions of the pairs 12', at locations 62 between
conductors 11, as is clear from FIG. 5. A close packed assembly is
thereby achieved. As before, LEDs 23 are mounted on exposed tops of
sequentially alternate conductors 11b; and LEDs 22 are likewise
mounted on exposed tops of sequentially alternate conductors 11a.
Each LED has a wire 63 connecting it to the top of a conductor 12
in a pair of such conductors, as at a junction as seen at 64.
Insulation is removed or penetrated to enable electrical
communication between LED wire 63 and the metal wire within a
conductor.
[0082] In FIG. 2, coolant is shown flowing at 66 parallel to the
plane of the conductor formed screen; and in FIG. 3, coolant is
shown flowing at 67 generally normal to the plane of the conductor
formed screen, and through the screen, for removing heat from the
LEDs and screen, such heat produced by LED operation. FIG. 3 is
generally like FIG. 5, except that the pairs of conductors 12' and
12' are spaced from the pairs 12" and 12" to form air passing
openings.
[0083] FIG. 4, which is an assembly similar to that shown in FIG.
1, illustrates provision of spaces 66 formed between successive
straight conductors 11 in the Y-direction, and between undulant
over and under extending conductors 12 in the X-direction. Those
spaces facilitate flow of coolant fluid through the screen or grid
of conductors. The X and Y directions are substantially normal to
one another.
[0084] It will be understood that the screen as shown facilitates
its bending or warping, particularly about an axis or axes parallel
to the X-direction extents of conductors 11 to conform the screen
to desired shape or shapes. This may alter the perceived LED
illumination emanating from different portions of the screen, as
may be desired.
[0085] In FIG. 6, the conductors 11 are arranged to extend in
spaced parallel relation in the X-direction, as in FIG. 1.
Successive conductors 12 are closely packed, so that portions 12a'
of conductors 12a closely nest between portions 12b' of conductors
12b, conductors 12a alternating between conductors 12b. LEDs 23 are
located on the exposed tops of conductors 11b, whereas LEDs 22 are
located on the tops of conductors 11a which alternate between
conductors 11b. Wires from LEDs 22 extend to junctions 26 at the
tops of conductors 12b overlying conductors 11b, whereas wires from
the LEDs 23 extend to junctions 30 at the tops of conductors
overlying conductors 11a.
[0086] FIGS. 13 and 14 show a mesh 90 of interwoven conductors 11
and 12, with LEDs 91 at the crests of conductors 11, which have
wave-like configuration, as do conductors 12. This facilitates
bending or warping of the screen or mesh about axes extending in
both the X and Y direction, to accommodate to desired curved
shaping as on object 92. LED wires 91a extend to junctions 94 on
conductors 12.
[0087] FIGS. 15 and 16 show a screen or mesh 100, similar to mesh
90 in FIGS. 13 and 14, with X direction conductors 101 interwoven
with Y direction conductors 102. A substrate 103 extends beneath
the mesh, and dielectric spacers such as spheres or balls 104 are
located between 100 and 103 to engage and position them relative to
one another. In FIG. 16, LEDs 106 mounted on crests of conductors
101, have wires 106a extending to junctions 107 on crests of
conductors 102.
[0088] FIG. 17 shows positioning balls 110 between the tops of
conductors 12 woven above and below conductors 11. Balls 110 also
serve as protection and spacing means. LEDs are mounted on
conductors 11 between conductors 12. A superstrate 111 may be
located at the tops of the balls 110. Superstrate 111 may be a
transparent plate, to pass light emitted by the LEDs.
[0089] FIGS. 18 and 19 show a mesh 120 similar to that seen at 90
in FIGS. 13 and 14. The "open-weave" conductors are seen at 111 and
112; and LEDs 113 are mounted on crests of certain conductors such
as 111. LED wires 130 extend to junctions 131 on conductors 112.
The latter may have concentric configuration.
[0090] FIGS. 20-23 show alternative screen and LED
configurations.
[0091] FIG. 24 shows a screen 120 like any of the described
screens, with cooling air 121 blown at 122 into a space 123 below
the screen, to flow adjacent the screen and upwardly through the
screen. A housing is seen at 124. Actuators 125 and 126 may be
provided to actively and repeatedly displace, deform or warp the
screen, as for an active sign display.
[0092] Referring now to FIGS. 25 and 26, the illustrated LED or LED
"pixel" package, or diode package 150 includes a light emitter or
emitters 151 within a transparent container, one example being a
glass tube 152 having a hemispherical end 152a. A window area 152b
is defined by tube 152, or container, for transmission of emitted
light in a direction or directions 153. A reflector 154 is located
within the tube, and has a reflecting surface 154a for reflecting
emitted light in a forward direction 153, through the window and to
the exterior. The reflector may have edges 154b engaging or
supported by the tube interior wall 152c.
[0093] An electrical lead or leads indicated at 156 extends with
helical configuration into the tube and within the tube, to the
emitter or emitters, that configuration providing support. The lead
or leads preferably has or have a flattened or generally
rectangular configuration seen in FIG. 26. Wires contained in the
lead or leads may include "red", "green" and "blue" (relating to
emitted light color) and an additional wire, such as an electrical
neutral or return wire, to the emitter or emitters. The wires may
consist of AWC32 copper multifilar and or AWC26 copper wire or
AWG26 4 conductor insulated copper multifilar wire helically wound
around a rectangular cross-section AWG18 insulated copper wire. A
metallic, as for example aluminum base 157, has an edge recess 158
receiving the end of the tube 152, and supporting the tube.
Specularly reflecting aluminum walls 159 and 160 are provided in
the tube, and support the reflector 154, as at endwise locations
161 and 162.
[0094] The base 157 defines a through opening 163 passing the lead
or leads; the base also defines an end recess 164 filled with
potting compound 165 as for example epoxy resin. The lead or leads
pass through that compound. The base also has an edge portion
defining an annular recess 168, for reception of a package support
or support portion 169, as for example a portion of the conductor
11a as seen in FIG. 1. The recess 168 preferably has cylindrical
wall configuration, allowing rotation of the diode about an axis
170 defined by the recess or conductor. Diode or pixel replacement
is also facilitated. Lead wires may be connected to conductors 11
and 12 of the screen, as referred to above.
[0095] FIG. 27 shows the LED packages 150 of FIGS. 25 and 26
arranged in a display sequence or configuration. FIG. 28 shows the
FIGS. 25 and 26 LED packages mounted to mesh defining conductors 11
and 12, so that the LED packages are carried by the mesh conductors
11 and are rotatable about axes 170, as referred to. Integrated
pixel electronics is thereby provided. Note leads 156 connected at
156a to conductors 12. FIG. 29 shows LED package 150 mounted on a
conductor 11, and transmitting light to a reflector 180.
[0096] FIG. 30 shows a sign or array employing LED packages as
disclosed. The display incorporates vertical conductors 300, with
representative addressing wires 301 and 302 extending at acute
angles, for example 45.degree. across and relative to wires 300.
Wires 301 are extensive of wires 302 in a geometric sense. Other
addressing wires are indicated in broken lines, as at 302a. LED
packages are shown at 303 carried by wires 300. This configuration,
shown schematically, achieves reduced lengths of addressing wires,
as compared with horizontal wires. Connections 304 and 305 to wires
300, 301, and 302a are made at the screen, i.e. array
perimeter.
[0097] FIGS. 31-33 are sections showing details of construction of
the LED addressing wires which may be of multifilar construction.
Referring to FIG. 31, wire 301, numerals 306 and 307 refer to LED
red light emitting pair; 308 and 309 refer to green emitting pair;
and 310 and 311 refer to blue light emitting pair. A pair of red
AWG 18 insulated copper wires is used to activate the red LEDs for
a row of pixels. This wire pair and its neighboring wire pairs may
be helically wound around an insulated central core that may serve
as a tensile element. AWG 26 insulated copper wires from the pixel
may be nested between wire pairs of like color. An insulated metal
retainer may be used to compress the pixel wires against the power
supply wires.
[0098] Numerals 313-315 designate three insulated copper wires from
the three pixels, respectively, nested between the referenced wire
pairs. A small amount of insulation is removed at wire regions to
establish electrical connection between 313 and 306 and 307;
between 314 and 308 and 309; and between 315 and 310 and 311. A
stainless steel retainer 316 extends about the wire assembly, and
holds the wires in compression at the central regions, for example
as seen at 317, 318, and 319 in FIGS. 32 and 33. The retainer may
take the form of a split ring fastener that engages the wires
313-315 and may yieldably deform them at their contact points
317-319.
[0099] FIG. 34 schematically shows a metal plate 316 that may be
used and positioned as an absorber of sunlight that passes through
a display sign array incorporating devices as described above. It
also blocks light transmitted toward the rear of the sign array. As
such, the plate 316 may be regarded as overlapping the array at the
rear thereof. The angled slits 316a that extend through the plate
pass cooler air (possibly blower induced) flowing in the space
between the plate and the array. Plate 316 also provides mechanical
protection at the back of the display. FIG. 34 also represents a
side view of an array of overlapping elements that absorb sunlight
and extraneous radiation while allowing the passage of cooling air.
The array creates a thermal chimney effect to further increase
cooling air flow and this effect may be further enhanced by the use
of array surfaces with high absorptivity for sunlight and low
emisstivity in the longwave infrared region. In addition the array
provides mechanical protection for signage and display
elements.
[0100] FIG. 35 is a section showing protective metallic screens 317
at the back and front sides of the display array schematically
indicated at 318. Such screens may pass cooling air, blower driven
at 319. FIG. 36 is like FIG. 35, but shows louvers or slots 320 in
place of screens 317.
[0101] Screens may be used in place of circuit boards and
conductors on or as film circuitry. Screens can provide power and
signal conduits as at 300 or 302 in FIG. 30, with reduced cost,
mass, and volume, while providing paths between the conduits for
flow of cooling fluids to allow systems/products with greatly
reduced thermal resistance and/or increased power density
operation. Screens may also allow optical communication between
circuit elements via open regions between the wires. Screens
greatly simplify the manufacture of 3D electronics, allow
mechanical compliance, and may behave somewhat elastically to
provide pressure type electrical contacts. Screens may have diodes
electrically connected to the junctions between crossing wires
and/or be in contact with electronic circuitry on chip or chips
that provides diodes and/or electrically switchable elements to
control the flow of electrons through the screen array. Connection
schemes such as solder and including ball grid arrays are also a
possible means of connection. Screen and chip arrangements include
"Z Fold" serpentine/sinuous screen with chips between each layer
and spiral/helical screens with chips between each layer/rotation.
Screens are also good candidates for neural net architectures.
Connection with input/output elements may be via ends/edges of
screens and employ contact means such as solder, conductive
adhesive, and/or mechanical/pressure contact. See 304 and 305 in
FIG. 30.
[0102] FIG. 28a shows modifications in the manner of supporting
LEDs and their electrical connections, in an array. The LEDs appear
at 500 and are adjustably, and/or removably supported on conductors
501, which may be power conductors, as described in FIG. 25.
Addressing wires or conductors, are shown at 502, and may take the
multi-filer form as shown in FIGS. 31-33. Wires 502 extend at acute
angles (for example 45.degree.) relative to conductors 501,
extending in direction or directions 504. Coolant gas passing
spaces between structure appear at 505. Local electronic circuitry,
in the LED packages are seen at 506. Pixel package circuitry is
indicated at 507 in the packages. Local addressing wire branches
502a extend (i.e. branch) from the wires 502 to 156, as described
above. Wires 502 and conductors 501 form the grid or screen.
Linking connectors 540 may be provided as sown to connect
successive conductors 501, so as to allow or restrict flexing of
the screen or array.
[0103] FIGS. 37-39 show rows and columns of light emitting packages
(LEDs) 401 generally of the type referred to above, and supported
by conductor wires 402 running vertically, in the drawing.
Addressing (control) wires appear at 403, and run at acute angles,
as for example 45.degree., relative to wires 402. Wires 402 and 403
form a grid, with coolant fluid passing passages 406 through the
structure. The packages 401 contain internal mirrors 407 and 408
convex toward one another to reflect LED emitted light. Clips 409
are connected to bulges 410 on wires 402, to retain the wires in
spaced relation as shown, and to block wire 402 rotation about
their axes. FIG. 40 is an end view of a clip. The LED packages are
electrically connected to wire 402 (that extend through grooves 412
in the bases of the LEDs), and to wires 403, via leads 413. See
also circuitry 506 and 507, as described above.
[0104] FIGS. 41-43 show a wire conduit 415, in the form of a
metallic channel, for example. It supports or contains closely
spaced conductor wires 402a in zone 416, and closely spaced
addressing wires 403a, in zone 417, outside the display or grid, or
at the edges of the grid. The items 402a and 403a sown in FIG. 41
represent wire cross sections, or wire passing openings in a
plastic sheet, or plate, or support 417, carried by the conduit.
Numeral 419 may represent a conduit support. See also FIG. 53
showing stabilizing tension springs 420 and 421 connected at 420a
and 421a to support 419.
[0105] FIG. 42, a top plan view, also shows studs 422 forming wire
terminals carried by conduit 415.
[0106] FIGS. 44 and 47 show conductor wires 402 having bends 402b
and receiving bosses or retainers 425. See also address wires 403
that loop at 403a about retainers 425. A holder 426 extends
crosswise of 402 to hold them in position. FIG. 45, like FIG. 42,
also shows wire bends 402b looping about retainers 425. Retainers
422 also anchor the addressing wires 403, having connections
403a.
[0107] FIG. 46 schematically shows parallel conductor wires 432
extending vertically, and addressing wires 433 extending at
45.degree. angles relative to wires 432, thereby forming a grid.
LEDs i.e. pixel packages 440 are carried by the grid, as described
above, and electrically connected to the wires 432 and 433.
Electronic controls to control the LEDs are indicated at 437. A
frame for the grid is shown at 438.
[0108] FIG. 48 schematically shows a pixel package 440 peripherally
attached to a conductor wire 432, as via an annular groove 440a in
440, allowing adjustable rotation of 440 (see arrows 442) about the
package axis 443. FIG. 49 shows adjustable rotation of the package
440 about the lengthwise axis of conductor 432. See arrows 444.
FIG. 50 schematically shows an array 446 of LED packages 440, with
the packages in different rows having different adjusted
angularities, for variably directing emitted light in selected
directions.
[0109] FIG. 51 schematically shows an array 450 of pixel packages
451, which have electronic control circuitry 452 within the pixel
envelopes. In FIG. 52, the modified array 450a of LED pixel
packages 451a has control circuitry 452a at edges of the array.
Array wires 453 and 454 form grids.
[0110] FIGS. 54 and 55 show LED pixel package elements the same as
in FIGS. 38 and 39. Emitted radiation is within included angle
.alpha., in FIG. 55. Azimuth or radiation is reduced by vertical
axis parabolic mirror trough, indicated at 460.
[0111] A preferred form of the invention appears in FIGS. 25-33 and
FIGS. 37-39.
[0112] As disclosed herein large-screen modular displays and signs
are enabled, along with various curvatures and complex geometric
forms. Also, large scale video displays, and projection displays as
for billboards are made possible. Low volume, low mass, low cost,
high brightness, high resolution and high efficiency are enabled.
Double sided displays can be provided. LEDs can be placed on
opposite sides of the screen, and the screen can serve as a pattern
for LED placement.
[0113] LED bases can be placed on a transparent substrate, or the
screen can be provided as a polymer film or sheet.
[0114] Screen and superstrate may collectively provide mechanical,
structural strength. Superstrate may be thin or layered to allow
second or third flexure modes. Superstrates may be thin to reduce
sideways transmission of radiation from LEDs. Some LED sideways
light transmission can be provided for integrating between
pixels.
[0115] Provision is made for use of means to use conductive/red
LEDs. Screen elements can be connected to side faces of LEDs via
conductive adhesives, solder, amalgams, indium, stabilite 22, and
conductive grease. A metallic superstrate can be used.
[0116] Red LEDs can be provided with two conductors on same side
(UEC red on sapphire) Superstrates may have high refractive indices
to increase usable radiation (polycarbonate 1.59)
[0117] Superstrates may have transparent adhesive layer,
thermoplastic, thermoset, pressure sensitive features.
[0118] The screen can be deformed after weaving, during
manufacture, or deform screen before and/or during weaving. Screen
warp and woof wires of different metals can be used to reduce the
possibility of electrical shorting.
[0119] Another modification comprises an array of light emitting
diodes periodically placed on the weft wires of a woven aluminum
and/or copper screen (wire cloth) with the weft wires acting as one
conductor, and the warp wires acting as the opposite conductor. The
wires may be electrically isolated at their crossing points by such
means as anodic coatings and/or by the addition of inorganic or
organic over-coatings. The LEDs can be activated by pulsed and/or
continuous current and may be addressed as a whole or in groups or
individually as in an active video display by control of conductor
energization. Woven wire screen provides a very low cost
substrate.
[0120] Additional benefits include efficient heat transport, low
mass, low volume, reel to reel manufacturing with screen travel
between reels and roll-up on a reel with LEDs placed in position.
This allows freedom of display shape, transportable in a roll,
ability to be held in tension, in a wide range of materials and
sizes.
[0121] A video display may include an X-Y grid of light emitting
diodes placed on an aluminum woven screen suspended or placed
between a transparent polycarbonate sheet and another enclosing
sheet on the opposite side. An aluminum sheet with gaps between the
screen and the enclosing sheet become sufficient to allow forced
air to enter and flow upward between the polycarbonate sheet and
the screen, through the screen and exiting at the top rearmost part
of the screen.
[0122] Conductor wires act as structural conductors, electrical
conductors, and thermal conductors, and may also be provided with a
black region made especially effective because of "cavity effect".
Wires may vary in size, materials, coatings etc. with axis, e.g.
stainless steel wire may be used in tension in one axis direction
and copper or aluminum wire of smaller diameter may be used in
opposite axis direction (i.e. X-Y axes).
[0123] Manufacture may include placement of a screen on PTFE coated
needle/cone array/drum to allow coating of die/wire bond/adhesive
attach/screen without clogging holes; then forcing fluid through
the screen to prevent clogging. Screens can be spaced apart by use
of beads or spheres.
[0124] Electrostatic or electromagnetic powering of LEDs is
possible, and particularly pulsed operation, as with LED video
displays. High applied voltage allows smaller conductor cross
sections.
[0125] LEDs with junction faces on metal, or with good junction
heat transfer/thermal capacitance, can withstand very high voltage
spikes.
[0126] Patterned superstrate and/or substrate may act as one
conductor and screen or substrate as another conductor.
[0127] Anisotropic screens may be provided with wires along one
axis of a different material than wires extending along another
axis (thickness, form, alloy. Tensile strength and flexibility may
be more important in one axis e.g. opposite roll axis or row axis;
dissimilar metals are more apt to form dielectric regions at points
of contact and this may be encouraged via processing and/or choice
of material properties and coatings; a current flow in one LED row
may be several times greater than current flow in another LED
row.
[0128] Advantages and benefits of the FIG. 25 to 28 described LED
device construction include:
[0129] SPATIAL TUNING: Benefits accruing from the ability to aim
the radiation from the emitters to the target include a reduction
in emitter cost and/or electrical system cost and/or operating cost
and/or increased radiation delivered to the target. The herein
described pixel package can be rotated as for example 360 degrees
around it's axis and 360 degrees around an axis perpendicular to
its' axis, and as a consequence has complete freedom of movement in
both elevation and azimuth.
[0130] HORIZONTAL AXIS OPTICS: The target audience for signage and
billboards typically moves horizontally as in vehicles. Horizontal
axis optics provide for optimum control as the horizontal angular
aperture is typically much greater than the vertical angular
aperture.
[0131] ANGULAR APERTURE CONTROL: Minimizing the radiation beyond
the angular extent needed for the task is an important element in
minimizing cost. Maximizing the aperture to emitter size ratio
allows a minimization of the angular extent of the output
radiation. The herein described pixel design allows for a
minimization of the output radiation by minimizing the emitter
array size via close emitter spacing and a narrow gauge substrate
and by maximizing the aperture size for a given pixel spacing.
[0132] BIFACIAL DISPLAY: Bifacial displays are possible with a
single array of bifacial pixels or via a forward and rearward
spaced pixel arrays, which may provide or allow differing
energizing content to the displays. The pixel package allows
mounting in front of or in back of the display "plane". This allows
one face to use pixel packages mounted on the front of the vertical
wires and facing forward, and the opposite face to use pixel
packages mounted on the opposite side of the wires and facing
rearward. The packages may be displaced vertically to allow
clearance.
[0133] TRANSPARENT DISPLAY: Displays can be made with a wide range
of transparency to suit a variety of end uses.
[0134] OPTICAL EFFICIENCY: The pixel design allows for use of a
linear emitter array coupled with a visible mirror film parabolic
trough, to control radiation in the vertical axis. Horizontal axis
radiation may be controlled by end reflectors of similar material
and these may be curved to aid in the control of the angular extent
of the radiation in the horizontal axis. This design minimizes the
average number of reflections and provides for high efficiency for
each reflection. The pixel optical system may be contained within a
cylindrical glass envelope for environmental protection. Additional
benefits of such an envelope include:
[0135] 1) functioning as a circular compressive element to
constrain the elastically deformed 3M VMF and thereby cause it to
form a parabolic curve; (The film is typically specularly
reflecting film such as 3M visible mirror film. The reflecting film
may be paired with/attached to additional film/s to provide the
desired mechanical and other properties. The film/s may also be
adhered to the container walls and/or constrained by
lands/ridges/bumps along the container walls.)
[0136] 2) functioning as a container for a wide range of liquids,
gels, solids, and/or smaller containers;
[0137] 3) functioning as a refractive optical element.
[0138] CONTRAST RATIO: Increasing the contrast ratio allows an
improvement in visibility and/or a reduction in radiative power for
a given visibility. The herein described configuration allows high
contrast ratio viewing by:
[0139] 1) Minimizing the angular extent of the output radiation and
increasing the aperture area of the output radiation reduces the
probability of sunlight or other extraneous radiation being
reflected from the `display" to the target/viewer,
[0140] 2) Optical porosity (low solidity), which allows a portion
of the radiation that would impinge on and possibly be reflected
into the target on a high solidity display pass through and be
absorbed on a subsidiary surface/s,
[0141] 3) Insuring all surfaces within the targets field of view
have very low reflectivity by means such as coating and
texturing.
[0142] DETECTOR/DETECTOR ARRAY: The described pixel may also
operate as detectors, alone or in conjunction with emitters.
[0143] The lifetime and efficiency of semiconductor devices (LEDs)
degrades strongly with increasing temperature. Provision is made
for reducing the thermal resistance between the emitters and the
local environment, and thereby increasing lifetime, reliability,
durability, and efficiency and reduce operating cost, pursuant to
provision of the following:
[0144] 1) A low solidity array which allows a portion of the solar
load to be diverted to subsidiary surfaces and thereby make a
smaller contribution to array heating. In addition, the open design
allows airflow in and around the array and in very close thermal
communication with the emitters.
[0145] 2) Wind enhanced cooling. A porous array allows the passage
of and the ability to transfer heat to the local air stream. Wind
speed increases strongly with increasing height and high mounted
signage and displays may benefit greatly from this cooling.
[0146] 3) Thermally induced convection cooling caused by the wire
array, the pixel packages, and by proper design of subsidiary
surfaces behind the array (horizontal axis overlapping
slats/louvers).
[0147] 4) Solar assisted cooling may be promoted by proper design
of subsidiary louvered absorber array behind the screen. Louver
surfaces with a high absorptivity for sunlight and a low infrared
emissivity may be used to further increase airflow.
[0148] 5) The pixel package enables use of a rectangular copper
substrate for LED mounting. This substrate acts as a thermal,
electrical, and structural conduit and its cross section may be
easily sized to provide sufficiently low thermal resistance. The
pixel package is thermally coupled to the row and column wires to
aid in the transport of heat to the local environment. In addition,
the pixel package may be liquid filled to allow reduced LED
operating temperature.
[0149] 6) Active cooling may be used if necessary, but its need and
its cost may be greatly reduced by the aforementioned features.
[0150] Provision is made for use of active and/or passively
addressed pixels. Local (pixel based) electronics may be included
in the pixel package and placed on the emitter substrate, behind
the reflector, in the aluminum bushing and/or in the hemispherical
cap. Local electronics may vary with application and include
capacitors, resistors, inductors, diodes, transistors, standard
integrated circuits such as 555 timers or application specific
integrated circuits. Multiplexing may be used to reduce the cost of
the electrical system, and the ability to multiplex is greatly
increased by minimizing the pixel output radiation required by
means discussed in the above optics section.
[0151] Provision is made for use of in-field replaceable pixels
that may be made to be replaceable from either side of the
screen.
[0152] Use of vertically oriented column/common wires and 45 degree
oriented row/addressing wires to allows large scale seamless
signage and displays with all pixels/electronics
addressable/accessible from the top or the bottom of the
screen.
[0153] Control electronics may be integrated into pixel packages;
and/or control electronics may be concentrated in modules or zones
at edge or edges of the arrays.
[0154] Provision is made for use of robust signage/displays created
by arranging a parallel array of large diameter vertically oriented
common/column wires in tension between horizontal upper and lower
rigid members. The upper end of each vertical wire may be formed
into a loop and affixed to and electrically isolated from the upper
rigid horizontal member. The lower end of each vertical wire may be
formed into a loop and elastically attached to and electrically
isolated from the lower rigid member by a stainless steel extension
spring. Both upper and lower mounts may serve to prevent rotation
of the vertical wires around their own axes. A parallel array of 45
degree row wires may be connected in tension between the upper and
lower rigid horizontal members by means analogous to those
described for the vertical wire array. The 45 degree row wires may
be constructed of a large diameter electrically insulated central
wire helically wound with a 6 strand small diameter multifilar
insulated wire array. The multifilar wire array includes paired
red, green, and blue wires. The 45 degree wire array may be placed
behind the vertical wire array and the pixel packages may be
mounted in front of the vertical wires. The pixel packages may be
mechanically connected to the vertical wires by plastic deformation
of the pixel package aluminum bushing and/or the wire and/or by
adhesives. The pixel common wire may be electrically connected to
the large diameter vertical common wire through the aluminum
bushing via wirebonding or pressure welding or directly to the
larger diameter wire by soldering or pressure type connection. Red,
green, and blue wires emanating from the pixel may be connected to
the 45 degree row wires by soldering or by pressure type
contacts.
[0155] The row and column wires may be constructed of aluminum to
reduce cost and weight for a given strength, electrical and thermal
conduction. In addition, electrically insulative coatings adhere
better and have longer life on aluminum than copper.
[0156] Signage and displays of simple or complex face or form
(circular or hyperbolic cylinders, cones and conoids, hyperbolic
paraboloids) may be assembled on site or shop fabricated by simple
techniques that lend themselves to manual or automated
fabrication.
[0157] Other important advantages are listed as follows:
[0158] 1. Organic Light Emitting Diodes: (OLEDS) may be used as
light emitters alone or in conjunction with inorganic LEDs. OLEDs
may be easier to apply to screen type substrates and may allow
reduced product cost.
[0159] 2. Multiplexing: The ability to tailor the angular extent of
the radiation output and the increased contrast provided by the
OnScreen design allows a greater degree of multiplexing and a
concurrent reduction in system cost.
[0160] 3. 45.degree. Scanning: 45.degree. scanning reduces line
artifacts compared to vertical or horizontal scanning and thereby
allows higher apparent resolution for a given number of pixels
and/or a reduced number of pixels for a given apparent
resolution.
[0161] 4. In Field Pixel Replaceability: The ability to replace
individual pixels in the field allows reduced maintenance cost.
[0162] 5. Freedom of Form: Array construction allows a wide variety
of signage/display forms. One example is a vertical axis
cylindrical display viewed from the inside and/or the outside and
with varying degree of array transparency determined by design.
[0163] 6. Shop Or Site Fabrication: The light weight and flexible
nature of the OnScreen array coupled with the mechanism of flexible
local linkage allows for shop fabrication of large area arrays.
[0164] 7. Pixel Level Voltage Reduction: Pixel "on-board" reduction
allows higher array supply voltages and thereby lower current
levels and reduced self-heating of array wiring and/or reduced wire
cross-sectional area.
* * * * *