U.S. patent application number 09/895354 was filed with the patent office on 2002-01-17 for led luminaire with light control means.
Invention is credited to Akiniwa, Taishi, Asahi, Nobuyuki, Hashizume, Jiro, Kamada, Kazuo, Koyama, Shoichi, Shiohama, Eiji, Sugimoto, Masaru, Suzuki, Toshiyuki, Tanaka, Takashi, Yamamoto, Shohei.
Application Number | 20020006040 09/895354 |
Document ID | / |
Family ID | 27339927 |
Filed Date | 2002-01-17 |
United States Patent
Application |
20020006040 |
Kind Code |
A1 |
Kamada, Kazuo ; et
al. |
January 17, 2002 |
Led luminaire with light control means
Abstract
An LED luminaire is formed such that a plurality of LED chips
are disposed three-dimensionally on an MID (molded interconnection
device) substrate in a rectangular plate shape, by mounting three
LED chips on bottom face of respective dents provided lengthwise
and crosswise in one surface of the MID substrate, the LED chips
including at least two types diffferent in luminous color,
desirably three types of red, blue and green colors. Any optional
light distribution characteristic is made thereby easily obtainable
depending on a configuration of the substrate, luminaire module can
be thinned, and such delicate color difference as white color and
day-light color of luminescent lamps is enabled by mixing the
luminous colors of the respective LED chips.
Inventors: |
Kamada, Kazuo; (Osaka,
JP) ; Koyama, Shoichi; (Osaka, JP) ; Asahi,
Nobuyuki; (Osaka, JP) ; Suzuki, Toshiyuki;
(Nara-shi, JP) ; Shiohama, Eiji; (Osaka, JP)
; Sugimoto, Masaru; (Osaka, JP) ; Yamamoto,
Shohei; (Osaka, JP) ; Hashizume, Jiro; (Osaka,
JP) ; Akiniwa, Taishi; (Osaka, JP) ; Tanaka,
Takashi; (Osaka, JP) |
Correspondence
Address: |
John H. Lynn
Suite F 200
2915 Redhill Ave.
Costa Mesa
CA
92626
US
|
Family ID: |
27339927 |
Appl. No.: |
09/895354 |
Filed: |
June 29, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
09895354 |
Jun 29, 2001 |
|
|
|
09199893 |
Nov 25, 1998 |
|
|
|
Current U.S.
Class: |
362/237 ;
257/E25.02; 257/E25.032; 362/555 |
Current CPC
Class: |
F21Y 2107/00 20160801;
F21Y 2107/50 20160801; H01L 2924/3025 20130101; H01L 2224/45144
20130101; F21Y 2107/90 20160801; H01L 25/0753 20130101; F21V 5/02
20130101; F21Y 2115/10 20160801; F21Y 2105/00 20130101; H01L 25/167
20130101; F21Y 2107/10 20160801; H01L 2224/73265 20130101; H05K
1/0284 20130101; H05K 1/182 20130101; H01L 2224/48091 20130101;
H01L 2224/48091 20130101; H01L 2924/00014 20130101; H01L 2224/45144
20130101; H01L 2924/00 20130101; H01L 2924/3025 20130101; H01L
2924/00 20130101 |
Class at
Publication: |
362/237 ;
362/555 |
International
Class: |
F21V 001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 25, 1997 |
JP |
9-322626 |
Nov 25, 1997 |
JP |
9-323550 |
Nov 25, 1997 |
JP |
9-323551 |
Claims
What is claimed is:
1. An LED luminaire comprising a plurality of LED chips, a
substrate on which the plurality of LED chips are mounted, and a
light control means provided to the substrate for controlling the
distribution of light emitted by the respective LED chips, wherein
the light control means includes at least one of a plurality of
dents and a plurality of protrusions formed at positions where the
LED chips are mounted.
2. The luminaire according to claim 1 wherein the substrate
comprises a resin molded printed-circuit substrate.
3. The luminaire according to claim 1 wherein the plurality of the
LED chips include at least two types of the LED chips mutually
different in luminous color.
4. The luminaire according to claim 1 wherein the substrate is
constituted for providing a regularity in the direction of emission
to the plurality of the LED chips.
5. The luminaire according to claim 1 wherein the substrate is
formed in multilayers the central portion of which is raised.
6. The luminaire according to claim 1 wherein at least one of the
plurality of the dents and a plurality of the protrusions of the
light control means are formed on both side surfaces of the
substrate.
7. The luminaire according to claim 1 wherein the light control
means comprises the substrate per se formed with a light
transmitting material.
8. The luminaire according to claim 7 wherein the LED chips are
respectively provided with a power-supplying electrode section made
of a transparent conductor.
9. The luminaire according to claim 1 wherein the LED chips
respectively comprise a P-type semiconductor and an N-type
semiconductor which are arranged substantially in vertical with
chip-mounting surface of the substrate.
10. The luminaire according to claim 1 wherein a fluorescent
substance is applied at least to the positions of mounting the LED
chips.
11. The luminaire according to claim 1 wherein the substrate is
provided at least partly with a metal plate as a ground of the
plurality of the LED chips, the chips being brought into contact
with the metal plate.
12. The luminaire according to claim 1 wherein the substrate is
provided integrally with a copper-clad metal substrate, the
plurality of the LED chips being mounted on copper-clad part formed
on one surface of the metal substrate to be a ground, and the light
control means comprises circuit elements mounted on the other
surface of the metal substrate.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates to an LED luminaire formed with a
plurality of light emitting diodes (LED) on a substrate.
DESCRIPTION OF RELATED ART
[0002] Conventionally, luminaires employing candescent lamp or
luminescent lamp as light source have been radiated infared and
ultraviolet rays in addition to visible rays, and such other rays
than the visible rays have been often affecting ill such objects
irradiated as art objects, foodstuffs and so on. Further, in these
luminaires, the light source, i.e., the lamp has its own life and
is required to be exchanged for new one.
[0003] Recently, a light emitting diode (LED) of a high luminance
has been suggested, and there have been used luminaires made not to
radiate such harmful rays as the infrared, ultraviolet and the like
rays, by means of such high luminance LED in a simple unit or, in
particular, a modulation of a plurality of LED's mounted on an LED
discrete substrate. These LED luminaires are advantageous in that
the life is prolonged as compared with such light sources as the
candescent and fluorescent lamps, the lamp exchange or the like
maintenance is freed, and handling ability is excellent.
[0004] While the LED luminaires have such various advantages as in
the above, they still have such drawbacks as will be referred to in
the followings. That is, LED is a single wavelength (single color)
so as not to be able to obtain the white color, and LED is also
strong in the directivity of light so that LED's of different
wavelength (luminous color) and mounted on the same substrate as
admixed will be unable to be mixed fully in their respective colors
so as not to be able to easily obtain the white color light source
but rather to cause, in particular, a shadow of the irradiated
object to appear in rainbow colors. Accordingly, it is impossible
to realize the delicate color difference between the white and
daylight colors, as in the case of the luminaire employing the
fluorescent lamp as the light source. Further, when LED's are
mounted on the substrate at a high density, heat generation at the
respective LED's will result in an elevated temperature, so as to
render the luminous efficacy and luminance to be deteriorated, and
the life of the respective LED's to be shortened. Since LED is
large in its height dimension, further, it has been a remarkable
trouble when the thinning of the device is intended.
[0005] For a related art of the kind referred to, a Japanese
Utility Model Laid-Open Publication No. 4-92660 of Machida et al.
discloses an LED luminaire in which LED's are arranged horizontally
on a mounting plane of the substrate, with which arrangement,
however, the light emitted by these LED's is limited only to be in
vertical direction with respect to the mounting plane of the
substrate, to be troublesome in the controllability of distribution
of light. A Japanese Patent Laid-Open Publication No. 1-283883 of
Ikeda discloses a resin molding of a substrate for mounting LED's
but this substrate still has been unable to realize a desired
control of the distribution of light.
SUMMARY OF THE INVENTION
[0006] An object of the present invention is to overcome the
foregoing problems, and to provide an LED luminaire capable of
easily attaining a desired distribution of light and of being
thinned.
[0007] According to the present invention, this object can be
realized by means of an LED luminaire comprising a substrate formed
to have at least one of a plurality of dents and a plurality of
protrusions, and a plurality of light emitting diodes disposed with
respect to each of at least one of the plurality of the dents and a
plurality of the protrusions.
[0008] Other objects and advantages of the present invention shall
become clear as the description advances with reference to
preferred embodiments of the invention shown in accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a sectioned view of the LED luminaire in an
embodiment according to the present invention;
[0010] FIG. 2 is a perspective view of the luminaire in FIG. 1;
[0011] FIG. 3 is a fragmentary, schematic sectioned view of another
embodiment of the present invention;
[0012] FIG. 4 is a perspective view of the luminaire employing the
embodiment of FIG. 3, with part thereof shown as removed;
[0013] FIG. 5 is a fragmentary, schematic sectioned view of further
embodiment of the present invention;
[0014] FIG. 6 is a perspective view similar to FIG. 2 of another
embodiment of the present invention;
[0015] FIG. 7a is an explanatory view for the arrangement of 1 cell
in the embodiment of FIG. 6;
[0016] FIG. 7b is an explanatory view for the arrangement in a
module comprising a plurality of cells in the embodiment of FIG.
6;
[0017] FIG. 8 is a fragmentary, schematic perspective view of
further embodiment of the present invention;
[0018] FIGS. 9-12 are fragmentary, schematic sectioned views
showing other embodiments respectively of the present
invention;
[0019] FIG. 13 is a schematic sectioned view of the embodiment of
FIG. 12;
[0020] FIG. 14 is a schematic plan view of the embodiment shown in
FIG. 10 of the present invention;
[0021] FIG. 15a is a fragmentary sectioned view as magnified of
another embodiment of the present invention;
[0022] FIG. 15b is a front view of the embodiment of FIG. 15a;
[0023] FIG. 15c is a cross sectioned view of the embodiment of FIG.
15a;
[0024] FIG. 15d is a vertically sectioned view of the embodiment of
FIG. 15a;
[0025] FIG. 16 is a fragmentary, schematic sectioned view of
another embodiment of the present invention;
[0026] FIG. 17 is a fragmentary, schematic side view of another
embodiment of the present invention;
[0027] FIGS. 18 and 19 are fragmentary sectioned views as magnified
of respective further embodiments of the present invention;
[0028] FIG. 20 is an explanatory view for the operation of another
embodiment of the present invention;
[0029] FIG. 21a is a fragmentary, schematic sectioned view of
another embodiment of the present invention;
[0030] FIG. 21b is a fragmentary, schematic sectioned view of
another embodiment of FIG. 21a;
[0031] FIG. 22a is a fragmentary, schematic sectioned view in
another aspect of the above;
[0032] FIG. 22b is a fragmentary, schematic perspective view of the
aspect in FIG. 22a;
[0033] FIG. 23 is a fragmentary sectioned view as magnified of
further embodiment of the present invention;
[0034] FIG. 24a is a fragmentary, schematic sectioned view of
another embodiment of the present invention;
[0035] FIG. 24b is an explanatory view for the relationship between
the wavelength and the intensity of light in the embodiment of FIG.
24a;
[0036] FIGS. 24 and 25 are fragmentary, schematic sectioned views
respectively of another embodiments of the present invention;
[0037] FIG. 26 is a fragmentary, schematic sectioned view of
further embodiment of the present invention;
[0038] FIG. 27 is a schematic plan view of the embodiment of FIG.
26;
[0039] FIGS. 28-33 are fragmentary, schematic sectioned views
respectively of further embodiments of the present invention;
[0040] FIG. 34 is a fragmentary, schematic side view of the
embodiment of FIG. 33;
[0041] FIG. 35 is a schematic perspective view, similar to FIG. 1,
of another embodiment of the present invention;
[0042] FIG. 36 is a fragmentary circuit diagram of the embodiment
of FIG. 35;
[0043] FIG. 37 is a schematic perspective view as disassembled of
another embodiment of the present invention; and
[0044] FIGS. 38-40 are fragmentary, schematic sectioned views
respectively of further embodiments of the present invention.
[0045] While the present invention shall now be described with
reference to the respective embodiments shown in the drawings, it
should be appreciated that the intention is not to limit the
invention only to these embodiments shown but rather to include all
alterations, modifications and equivalent arrangements possible
within the scope of appended claims.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0046] In FIGS. 1 and 2, there is shown an embodiment of the
present invention, in which a three-dimensional circuit substrate
10 in the form of a molded interconnect device (MID), in a
rectangular plate shape is formed to have in one surface many dents
11 arranged lengthwise and crosswise, and preferably three light
emitting diode elements (which shall be hereinafter referred to as
"LED chip") 1 are mounted to a part or most part of a bottom, side
or so face of each dent 11.
[0047] Next, manufacturing steps of the above substrate 10 shall be
described. An insulative base is formed through an injection
molding with such electrically insulative material as polyimide,
polyether imide, polyamide, liquid crystal polymer and the like, or
ceramics, for example, Al.sub.2O.sub.3, SiC, Si.sub.3N.sub.4,
ZrO.sub.2 and the like, and the insulative base is made into a
three-dimentional configuration by providing the dents 11 at
mounting positions of the LED chips 1.
[0048] After subjecting this insulative base to an alkali
degreasing, its surfaces are plasma-processed to activate the
surfaces and to finely rougthen them. Thereafter, a metal film,
that is, a plating ground layer of copper, silver, gold, nickel,
platinum, paradium or the like is formed on the surfaces of the
insulative base, by means of sputtering, vacuum evaporation or the
like. This metal film should preferably be of a thickness of about
0.1 to 2.0 .mu.m.
[0049] Then, such electromagnetic wave as laser or the like is
radiated to partly remove the metal film. For this laser, a second
harmonic generation YAG laser, YAG laser, excimer laser or the like
is preferable. By scanning the laser beam by means of a
galvanomirror, other parts than circuit parts 12 on which a circuit
is formed on the surface of the insulative base, that is,
non-circuit parts 13 forming insulating space between the circuit
parts 12 are irradiated, and the metal film in boundary zone
between the circuit parts 12 and the non-circuit parts 13 is to be
removed by radiating the laser beam along a pattern of the
non-circuit parts 13, with respect to at least the boundary zone of
the non-circuit parts 13 with respect to the circuit parts 12.
[0050] Next, an electric copper plating is performed through, for
example, a copper sulfate plating bath (copper sulfate 80 g/l,
sulfuric acid 180 g/l, chlorine and a brightner) while supplying an
electric power to the circuit parts 12, an electric nickel plating
is performed with, for example, a Watts bath (nickel surfate 270
g/l, nickel chloride 50 g/l, boric acid 40 g/l and a brightner) ,
an electric gold plating is performed with, for example, articles
sold as TEMPEREX 401 of a firm EEJA, and a circuit substrate on
which metal films of a predetermined thickness, that is the
three-dimensional circuit substrate 10 is obtained. Residual metal
films at the non-circuit parts 13 may be removed as required, by
means of a soft etching or the like.
[0051] The LED chips 1 are mounted in the dents 11 of the substrate
10 obtained through the foregoing process, and the circuit parts 12
and LED chips 1 are electrically connected (die-bonding) with an
electrically conductive adhesive. Thereafter, top electrodes of the
LED chips 1 and the circuit parts 12 are connected through gold
wires (wire-bonding). Inner surface 11a of the dents 11 in which
the LED chips 1 are mounted is mirror-finished to render the dents
to act also as a reflector, so that a high luminance and a high
efficiency can be attained. Next, a transparent resin is charged in
the dents 11 to seal the LED chips 1. At this time, the substrate
10 should preferably be provided with a dam for preventing the
transparent resin from flowing out of the dents 11. Finally, a
diffuser plate 15 consisting of a transparent resin is mounted to
the surface, that is, the mounting surface of the substrate 10, and
a module of the LED luminaire in the present embodiment is
completed.
[0052] Since a plurality of the LED chips 1 are mounted in the
dents 11 to dispose the chips in three-dimensional manner
preferably on the three-dimensional circuit substrate 10 using the
MID (molded interconnect device), it is enabled to easily attain
the optional light distribution characteristic in accordance with
the configuration of the substrate 10, and to render the module to
be thinner than conventional ones in which many light emitting
diodes of discrete type are disposed on the substrate. Further, by
mounting at least two types of the LED chips 1 different in the
luminous color, desirably three types of red, blue and green, it is
made possible to realize such delicate color difference as that
between the white and day-light colors in the case of the
fluorescent lamp, with the light of the whole module by mixing the
luminous colors of the respective LED chips 1.
[0053] While in the present embodiment the three-dimensional
configuration is formed by providing the dents 11 in the substrate
10, the invention is not limited to this only but, for example, the
substrate 10 may be provided with protrusions for mounting thereon
the LED chips 1, or the substrate 10 may be formed in any one of
various three-dimensional configurations, to dispose the LED chips
1 three-dimensionally.
[0054] In FIG. 2, the diffuser plate 15 made of the transparent
resin is omitted for a clear illustration of the disposition of the
LED chips 1 in the dents 11 for the entire luminaire as well as the
relationship in the electrical connection between the LED chips 1
and the circuit parts 12. Further, the LED chips 1 are formed as
molded with a transparent resin, for example, so as to be easy to
accommodate in the dent 11.
[0055] In FIG. 3, there is shown another embodiment of the present
invention, in which the luminaire is constituted such that a
plurality (for example, 100 pieces) of the LED chips 1 are mounted
on a surface of a resin-made substrate 10 (for example, 50.times.50
mm) , a molded layer 10A of a transparent acrylic resin is formed
on the surface of the substrate 10 to seal the LED chips 1, and a
microlens plate 27 formed to have many microlenses as the optical
control means for performing the emission control is disposed in
consideration of the distribution of light of the entire LED
luminaire 30 being made into a module, and the distribution of
light is so set by the microlens plate 27 that light emitting angle
of the entire LED luminaire 30 will be, for example, -60.degree. to
60.degree..
[0056] Referring also to FIG. 4 in addition to FIG. 3, an
illumination appliance 31 employing the above LED luminaire 30 is
disposed on the lower surface of an appliance body 32, and the
lower surface of the body 32 is covered by a light transmitting
lid. In the present embodiment, therefore, the light distribution
control is enabled to be efficiently performed by disposing the
plurality of LED chips on the single substrate 10, and the
microlens plate 27 allows such light distribution control to be
performable more efficiently, in conjunction with the light
distribution control attained by controlling the direction of
mounting of the LED chips 1.
[0057] In another embodiment shown in FIG. 5 of the present
invention, in contrast to the microlens plate 27 formed separately
from the molded layer 10A sealing the LED chips 1 in the embodiment
of FIGS. 33 and 34, the molded layer 10A is formed to be provided
on its surface with microlens section 27a as the optical control
means for controlling the distribution of light of the respective
LED chips 1, with the surface of the layer 10e spherically worked
or worked into any optional configuration. Other constituents are
the same as those in the embodiment of FIG. 3.
[0058] In this case, it is also possible to form the optical
control means for a simultaneous light distribution control with
respect to the light from a plurality (two to an optional number)
of the LED chips 1, instead of attaining correspondence of the
respective LED chips 1 to the optical control means. Accordingly,
the light distribution control as shown by arrows can be realized
by means of the microlens section 27a with respect to the light of
the LED chips 1 in the LED luminaire 30 of the present
embodiment.
[0059] Since the molded layer 10A of the sealing material is made
integral with the microlens section 27a in the present embodiment,
there is an advantage that any light loss occurs less to render the
efficiency excellent, and the light distribution control as to the
plurality of LED chips 1 is rendered easier.
[0060] On the other hand, there remains an inconvenience that, due
to the mounting of many LED chips 1 onto the single substrate 10,
the whole of the substrate 10 must be exchanged when even one or
part of the LED chips 1 cannot be lighted because of, for example,
failure occurring during the manufacturing steps or deterioration
with age.
[0061] Now, in another embodiment shown in FIG. 6 of the present
invention, the luminaire is featured in that a module with a
combination of monochromatic LED chips 1a-1d of such four different
colors as red, green, blud and yellow made as one unit is regarded
as one cell S, and the LED luminaire is constituted by combining a
plurality of the cells S.
[0062] That is, the above LED chips 1a-1d of four colors are
mounted as disposed in a matrix state to the respective dents 11 of
the sheet-shaped substrate 10 formed through the same process as in
the embodiment of FIG. 1 (see also FIG. 7a). Each dent 11 in which
the LED chips 1a-1d of four different colors are thus mounted is
regarded as one cell S, and the cells S are cut into every cell at
chain line portions in FIG. 6 by means of a dicing saw. Then each
cell S thus cut is mounted again to a printed substrate or the like
(see FIG. 7b).
[0063] According to the present embodiment as has been described,
the LED luminaire is constituted such that each cell S containing
the four LED chips 1 mounted in each dent 11 is made as one unit,
and a plurality of such cells S are combined, so that, upon
occurrence of non-lighted state at part of the LED chips 1 due to a
failure apt to occur in the manufacturing steps or an inherent
deterioration with age, only one cell S containing the particular
non-lighted LED chip 1 may be exchanged with a good one, to allow
the LED luminaire repaired at low costs. Further, by combining the
cells S different in color mixing or light distribution
characteristic, there arises an advantage that the LED luminaire
for decoration use can be realized with a simpler arrangement.
[0064] In another embodiment shown in FIG. 8 of the present
invention, the luminaire is featured in that means for a minute
vibration of the LED chips 1, i.e., a micromachine section 38 in
the present embodiment is provided to the MID substrate 10.
[0065] The micromachine section 38 is constituted by three beam
sections 38a supported at one end in a cantilever form, and crystal
plates 38b provided on the beam sections 38a, and the LED chips 1
are provided in the vicinity of respective free ends of the beam
sections 38a. Further, a lens 39 should preferably be provided in
front of the LED chips 1.
[0066] Next, manufacturing steps of the substrate 10 of the present
embodiment are described only as to different respects from the
embodiment of FIG. 1. The substrate 10 is the MID substrate made of
a ceramic, for which a mixture as kneaded of, for example, alumina
powder, a slip agent and a resin is injection molded, and thus
molded article is degreased, dried and sintered to prepare a
ceramic molded article (molded substrate). Thereafter, this molded
substrate is alkali-degreased, and surfaces of the ceramic are
plasma-processed for the surface activation and fine roughening.
Then the metal film of copper, silver, gold, nickel, platinum,
palladium or the like (plating ground layer) is formed on the
surfaces of the ceramic through such proper process as sputtering,
vacuum evaporation or the like. At this time, the metal film should
preferably be of a thickness about 0.1-2.0 .mu.m. Thereafter, the
patterning is performed in the same manner in the embodiment of
FIG. 1, thin crystal plates 38b are mounted on the beam sections
38a, the LED chips 1 are mounted thereon, and the LED chips 1 are
mounted thereon, to complete the LED luminaire module.
[0067] Then, with an application of a voltage to the micromachine
section 38, the beam sections 38a can be vibrated because of a
reverse piezoelectric effect of crystal, and it is enabled to cause
the mounted LED chips 1 on the beam sections 38a to be finely
vibrated.
[0068] Accordingly, it is possible to obtain optional color mixing
and light distribution characteristic, by causing specific ones of
the LED chips 1 finely vibrated, and also to improve flickering
characteristic which gives to people an unpleasant feeling.
[0069] In causing a new light source to appear in place of the
fluorescent lamp, on the other hand, there arises an event where an
emission of white light close to the solar light is required.
Pereceiving this respect, another embodiment of FIG. 9 arranges the
LED chips 1 of different luminous colors to prepare a desired color
with several types of colors blended, and the light distribution
control is performed by the optical control means acting to blend
the light of different colors.
[0070] That is, the modular LED luminaire 30 is constituted such
that four LED chips 1 including, for example, an LED chip 1B
emitting blue light, LED chip 1G emitting green light, LED chip 1R
emitting red light and LED chip 1Y emitting yellow light are
disposed on the resin-made substrate 10 at predetermined intervals,
prisms 28B, 28G, 28R and 28Y corresponding respectively to the LED
chips 1B, 1G, 1R and 1Y are disposed in front of the chips, and the
respective colors of light from the respective LED chips 1B, 1G, 1R
and 1Y are mixed at the central part of the substrate 10 through
the light distribution control by means of the prisms 28B, 28G, 28R
and 28Y into a white light W.
[0071] In the above embodiment, it is possible to obtain
substantially white light W, which can be employed for various
uses. In this case, it is also possible to obtain any optional
color of light by controlling the distribution of light with such
optical control means as the prisms or the like.
[0072] In another embodiment shown in FIG. 10 of the present
invention, the luminaire is featured in that the substrate is
formed to provide to the light emitting direction of the plurality
of LED chips 1 a regularity, and, as seen in FIG. 10, the substrate
10 is formed to have a surface sawtoothed in section on the
mounting surface side, and the LED chips 1 are mounted on slanted
side faces 10a of respective sawtoothed ridges.
[0073] Generally, mounting direction to the substrate 10 and light
emitting direction have the regularity, but it is possible to
obtain desired characteristics of light distribution and light
focusing, by forming the MID substrate 10 in an optional three
dimensional configuration.
[0074] Since the completed module is so formed that the mounted LED
chips 1 are faced regularly in one direction, there arises an
advantage that the emitted light is distributed in one direction to
improve the luminous efficiency.
[0075] According to the present embodiment as has been described,
further, the substrate 10 is formed to provide the regularity to
the light emitting direction of the plurality of LED chips 1, so
that there arise advantage that the light distribution
characteristic can be easily controlled in accordance with the
configuration of the substrate 10, and that the utilization is made
excellent by the light focusing and distribution taking into
account the whole module. Further, as the light distribution can be
controlled by means of the configuration of the substrate 10, such
optical means as a lens is made unnecessary advantageously.
[0076] Further, in the above case, saw-tooth shaped slanted side
faces 10a as the light control means may also be formed on the
surface of the substrate 10 in a plurality, and the LED chips 1 are
mounted on the slanted side faces 10a so as to render their p-n
junction plane to be substantially vertical to sloped mounting
surface of the slanted side faces 10a. As the LED chips 1 radiate
the light in all direction in the p-n junction plane, the light
radiated from the LED chips 1 is made substantially vertical to the
surface of the slanted side faces 10a. Here, the surfaces of the
slanted side faces 10a are formed to be mutually parallel, and
therefore the emitted light of the respective LED chips 1 will be
also mutually parallel, whereby it is enabled to radiate parallel
light from the LED luminaire module, to improve the utilization of
light.
[0077] Since in this way the surface of the substrate at positions
where the LED chips 1 are mounted is formed in such three
dimensional configuration preferably as the saw-tooth shape and so
on taking into account the distribution of light in the case when
the plurality of the LED chips 1 are disposed, it is enabled to
render a provision of separate optical means unnecessary, and the
light of the LED chips can be utilized highly efficiently.
[0078] Further, in contrast to the embodiment of FIG. 10 in which
the LED chips 1 are mounted on the slanted side face 10a of the
substrate 10, the LED chips 1 will be so arranged, as shown in FIG.
11, that light emitting direction of the respective LED chips 1
will be turned in a specific direction or, for example, converged
to an object. In this aspect, the luminaire can be remarkably
improved in the light distribution characteristic and the light
focusing characteristic with respect to an existing object or
objective zone.
[0079] In FIG. 12, there is shown another embodiment of the present
invention, in which the LED luminaire made in a module is so
constituted that the substrate 10 carrying a plurality of the LED
chips 1 per se is provided with a light control means 11A
constituted by small continuous dents for controlling the light
distribution of the respective LED chips 1, the light distribution
of the LED chip 1 is thereby made controllable as desired without
provision of any other optical means than the substrate 10, and the
LED chip 1 is improved in the utilization of light.
[0080] In another embodiment shown in FIG. 13, further, the LED
luminaire is provided with a substrate 10 substantially of 50 mm in
outer diameter in common, and a surface of the substrate 10 is
polished to form a paraboloid 10b which functions as the light
control means and also as a reflector surface. On the paraboloid
10b of this substrate 10, a plurlality of the LED chips 1 are
mounted so that their p-n junction plane (boundary plane between
p-type and n-type semiconductors) will be substantially vertical
with respect to the paraboloid 10b. In this case, the LED chips 1
emit the light in all direction in the p-n junction plane, so that
the light is radiated from the LED chips 1 substantially in
vertical direction with respect to the paraboloid 10a, and the
paraboloid 10a is so formed as to concentrate the emitted light of
the respctive LED chips 1 to concentrate to a single point in the
space.
[0081]
[0082] In another embodiment shown in FIG. 14 of the present
invention, the luminaire is provided with the substrate 10, a
plurality of the LED chips 1 mounted on the surface of the
substrate 10 in a matrix shape, and a reflector surface 10c formed
with, for example, aluminum film on the surface of the substrate 10
between adjacent ones of the LED chips 1. And in the present
embodiment the aluminum film high in the reflection efficiency is
employed for the reflector surface 10c, it is not necessary to
limit the reflector surface 10c to be of the aluminum film, but any
other metal material than the aluminum film and high in the
reflection factor such as silver may be employed. Further, when an
insulative substance is employed as the material for the reflector
surface 10c, it is possible to avoid any danger of short-circuiting
between the LED chips 1 or a wiring pattern (not shown) forming a
lighting circuit for the LED chips 1 and the reflector surface
10c.
[0083] Generally, the LED chip 1 is to emit the light upon movement
of electrons on the p-n junction plane with a current made to flow
through the p-n junction in forward direction, and the light
emitting direction will be in all direction in the p-n junction
plane. Therefore, in an event where the LED chips 1 are disposed on
the substrate 10 so that their p-n junction plane will be
substantially vertical to the surface of the substrate 10, the
light is radiated not only on the front side of the substrate 10
but also to directions parallel to the substrate 10 or in
directions toward rear surface of the substrate 10. Due to this, an
effective utilization of the emitted light of the LED chips 1 is
limited when the surface of the substrate 10 only is attempted to
be made into the three-dimensional configuration as in the
embodiment of FIG. 14. Accordingly, by causing the radiated light
from the LED chips 1 in substantially parallel direction with the
substrate 10 to be reflected in a desired direction by the
reflector surface 10c as the light control means, it is made
possible to utilize not only direct light radiated from the LED
chips 1 onto the front side of the substrate 10 but also the light
radiated from the LED chips 1 can be utilized, the utilization of
the emitted light of the LED chips 1 is elevated, and the intensity
of light of the modular LED luminaire can be raised
sufficiently.
[0084] Further, the reflector surface 10c may be formed three
dimensionally so as to be able to reflect the light from the LED
chips 1 in a desired direction. Also, the reflector surface 10c may
be so formed that the direct light radiated from the LED chips 1 on
the front side of the substrate 10 and the relfected light by means
of the reflector surface 10c will be respectively radiated in
different directions, and the LED luminaire can be increased in the
variation of the light distribution.
[0085] While in the above embodiment of FIG. 14 the reflector
surface 10c for reflecting the emitted light of the LED chips 1 in
the desired direction is formed on the surface of the substrate 10,
another embodiment shown in FIGS. 28a-28d of the present invention
employs an arrangement in which the wiring pattern of the lighting
circuit for the LED chips 1 formed on the surface of the substrate
10 is made to also act as the reflector surface 10c.
[0086] In this case, as shown in FIG. 15a, plated nickel layers 17
constituting the wiring pattern of the lighting circuit for the LED
chips 1 are formed on the surface of the substrate 10. At end parts
of the plated nickel layers 17, terminal sections 18 comprising a
plated gold are are formed, and the p-type and n-type
semiconductors of the respective LED chips 1 are mounted onto these
terminal sections 18 with the soldering or electrically conductive
paste employed. Further, as shown in FIG. 15b, three LED chips 1
are connected in series in forward direction through the plated
nickel layer 17, and three of units 20 each comprising such three
LED chips 1 are provided. The respective units 20 are mutually
short-circuited at the plated nickel layers 17 on both side ends
through short-circuit sections 21, and a circuit in which the
three, series connected LED chips 1 are connected mutually in
parallel is formed.
[0087] In this case, the LED chips 1 are mounted on the substrate
10 so that the p-n junction plane will be substantially vertical to
the surface of the substrate 10, slanted side faces 10a are formed
around the LED chips 1 mounted on the substrate 10 so as to
protrude on the front side of the substrate 10 as separated from
the LED chips 1, and the plated nickel layers 17 on the slanted
side faces 10a are reflecting the emitted light from the chips in a
desired direction.
[0088] As has been described, the LED luminaire of the present
embodiment employs the plated nickel layers constituting the wiring
pattern also as the reflector surface, so that the reflector or so
is not required to be separately formed, the circuit design can be
performed without taking into account the contact between the
reflector surface and the wiring pattern, and the freedom of the
design is made high. Further, in order to increase the reflected
light by means of the plated nickel layers 17 as a whole of the
modular LED luminaire, non-conductive sections 22 on the surface of
the substrate 10 may be minimized in the surface area and the
plated nickel layers 17 may be increased in the surface area.
[0089] In another embodiment as shown in FIG. 16 of the present
invention, the luminaire is featured in that the MID substrate 10
is formed to have sequential protrusions 28 in multilayers so as to
be in a so-called tower configuration or a spiral configuration as
a whole in which the protrusions 28 are raised sequentially to be
higher towards the center, and a plurality of the LED chips 1 are
disposed on the respective layers of such protrusions 28.
[0090] The substrate 10 is injection-molded using a mold made in
the tower configuration. Following steps are in common with the
embodiment of FIG. 1 and their description is omitted, except that
the sealing with the synthetic resin is not performed after the
mounting of the LED chips 1 to the substrate 10.
[0091] On the other hand, the power supply to the LED chips 1
causes temperature of the chips to rise and an ascending current to
occur with ambient air of the chips warmed, the air thus ascends
along the protrusions 28 of the substrate 10, while air at a lower
temperature is caused to be introduced from lower part of the
substrate 10 to drive the heat thereout and to cool it.
[0092] In the present embodiment as has been described, it is
enabled to prevent the temperature rise from occurring in the LED
chips 1 with the heat of the chips dispersed by means of an air
current, i.e., a convection, since the whole body of the substrate
10 is made in the so-called tower or spiral configuration by the
formation of the multilayered protrusions 28 on each layer of which
the LED chips 1 are provided, whereby the luminous efficiency and
luminance of the LED chips 1 can be prevented from being
deteriorated, and the life of the chips can also be prolonged.
[0093] In an conventional discrete type light emitting diode, the
epoxy resin for sealing the LED chips, for example, are formed into
a cannon ball shape so as to act as a lens, to be able to radiate
the light substantially in all direction of 360.degree., whereas,
in the case where a plurality of light emitting diodes are to be
mounted on the substrate, the light radiation in all radial
directions is made difficult due to the interception of the
substrate.
[0094] In another embodiment shown in FIG. 17 of the present
invention, the luminaire is featured in that a pluraity of dents 36
are formed in both side surfaces of the MID substrate 10, and the
LED chips 1 are mounted to the bottom of the respective dents 36,
so that the light can be radiated substantially in all
circumferential directions of the substrate 10. Manufacturing steps
for this substrate 10 are the same as in the embodiment of FIG. 1
and their description is omitted.
[0095] According to the present embodiment as described above, a
plurality of the dents 36 are formed in each of both side surfaces
of the substrate 10 and the LED chips 1 are mounted to the bottom
of the respective dents 26, so that the light can be radiated
substantially in all directions, and the luminaire can be used in
similar manner to the conventional fluorescent and candescent
lamps. Further, with mounting density of the LED chips 1 with
respect to the substrate 10 increased, there arise advantages that
the entire luminance can be improved, and further that the design
freedom of the light distribution is enlarged.
[0096] Further, as the LED chip 1 emits the light in all direction
in the plane of the p-n junction, the light emitted from the LED
chips 1 towards the substrate 10 is intercepted by the substrate 10
in the event where the LED chips 1 are disposed on the substrate 10
to position the p-n junction plane substantially vertical to the
surface of the substrate, even though various configurations of the
substrate 10 and mounting direction of the LED chips 1 are
observed, and it is difficult to utilize all emitted light of the
LED chips 1. In another embodiment as shown in FIG. 18 of the
present invention, therefore, a light transparent resin is employed
as the material of the substrate 10 for mounting the LED chips 1,
so that the light radiated to the side of the substrate 10 can be
utilized as transmitted to the other side of the substrate 10.
[0097] That is, the luminaire is constituted by the substrate 10
formed with a transparent acrylic resin, LED chips 1 disposed on
the substrate 10 to position the p-n junction plane substantially
vertical to the surface of the substrate 10, and transparent
sealing 23 formed on the surface of the substrate 10 for protecting
the LED chips 1. While in this case the acrylic resin is employed
for the material of the substrate 10, the material is not required
to be limited to the acrylic resin but may be such transparent
resin as polycarbonate or the like other than the acrylic
resin.
[0098] Now, with the use of the light transparent material for the
substrate 10 and sealing 23, the light emitted from the LED chips 1
towards the substrate 10 is transmitted through the substrate 10 to
be radiated to the exterior on the rear surface side of the
substrate 10, and the light radiated on the front surface side of
the substrate 10, i.e., on the sealing 23 side is transmitted
through the sealing 23 to be radiated to the exterior. Accordingly,
the light control means is constituted by the substrate 10 formed
with the light transparent resin per se, so that the light radiated
on the front side as well as the light radiated on the rear side of
the substrate 10 can be utilized, and the utilization of the light
of the LED chips can be elevated. While in the present embodiment
the substrate 10 as a whole is formed by the transparent resin, it
is possible to form the substrate 10 with the transparent resin
only at portions where the LED chips 1 are mounted.
[0099] In order to electrically connect the LED chips 1 mounted on
the substrate 10 to the wiring pattern formed on the substrate 10,
it is required to provide on the LED chips 1 an electrode section
made of such metal material as aluminum and to connect this
electrode to the wiring pattern on the substrate 10 by means of
bonding wire, whereas there remains a problem that, as the
electrode section formed on the LED chips is not transmissive to
the light, the emitted light of the LED chips 1 is intercepted by
such electrode section, and a shadow is cast. In another embodiment
shown in FIG. 19, on the other hand, a transparent, electrically
conductive member having the light transmission properties is
employed for the electrode section for power supply to the LED
chip, and the emitted light of the LED chips 1 can be prevented
from being intercepted.
[0100] Accordingly, the luminaire comprises the substrate 10 made
of a resin which does not transmit light, an electrode section 24
formed on the surface of the substrate 10, a plurality of the LED
chips 1 mounted on the electrode section 24, and a further
electrode section 24a provided on the top of the respective LED
chips 1, wherein the electrode sections 24 and 24a are both formed
with indium-tin oxide (ITO) which is a transparent conductor. In
this case, the n-type semiconductors 1a of the respective LED chips
1 are electrically connected to the one electrode section 24 and
the p-type semiconductors 1b are electrically connected to the
other electrode section 24a. Further, the electrode section 24 is
electrically connected to the wiring pattern (not shown) formed on
the substrate 10, while the electrode section 24a is electrically
connected through a bonding wire (not shown) to the other wiring
pattern formed on the substrate 10. Thus, the LED chips 1 are
connected through the electrode sections 24 and 24a to the wiring
patterns. Further, the protrusions 10c are formed on the substrate
10 to be between adjacent ones of the LED chips 1, the light
radiated from the p-n junction plane of the LED chips 1 is
reflected on the protrusions 10c of the substrate 10 and is
radiated in a direction of desired light distribution.
[0101] Since the transparent electrode sections 24 and 24a are
employed for electrically connecting the LED chips 1 to the wiring
pattenrs, the emitted light of the LED chips 1 is not intercepted
by the electrode sections 24 and 24a, so that the utilization of
the light of the LED chips 1 can be improved, and any loss of the
emitted light can be reduced.
[0102] While in the present embodiment ITO is employed for the
electrode sections 24 and 24a, they may not be limited to ITO, but
such other transparent conductor than ITO as cadmium-tin oxide
(CTO) or the like may be used. Further, with a use of a substrate
of light transmission properties as the substrate 10, the emitted
light of the LED chips 1 can be prevented from being intercepted,
and the utilization of the emitted light of the LED chips 1 is
further improved.
[0103] On the other hand, the LED chip 1 emits light upon movement
of electrons at junction boundary plane between P-type
semiconductor 1a and N-type semiconductor 1b, which light is
radiated in all directions in a plane including the junction
boundary plane, while it is apprehended that the light is
intercepted in the direction in which the LED chip is mounted to
the substrate 10 or by the metal wire 14, so that the radiating
direction of light is restricted and shadows are cast (see FIG.
20).
[0104] Here, in the present embodiment, the luminaire is featured
in that, as shown in FIGS. 21a and 21b, the LED chip 1 is disposed
to position the P-type and N-type semiconductors 1a and 1b to be in
a row substantially vertical to the mounting surface of the
substrate 10. Other respects in the arrangement are the same as in
the embodiment of FIG. 1 and their description is omitted here.
[0105] As shown in FIGS. 21a and 21b, in this case, the part of the
substrate where the LED chip 1 is mounted is raised one stage from
surrounding part, pads 33 are provided on both sides of the raised
parts, and the connection of these pads 33 to the P-type and N-type
semiconductors 1a and 1b of the LED chip 1 is performed by means of
soldering or the electrically conductive adhesive. Here, as the LED
chip 1 is mounted onto the raised part, so that any short-circuit
trouble can be prevented from occurring at the time of such
connection. For the LED chip 1, one of a cube of 0.3 mm, for
example, is desirable.
[0106] According to the present embodiment as has been described,
the LED chip 1 is disposed to position the P-type and N-type
semiconductors 1a and 1b in the row substantially to be parallel
with the mounting surface of the substrate 10, so that the junction
plane of both semiconductors will be substantially orthogonal to
the surface of the substrate 10, the emitted light from the LED
chip 1 is radiated in the direction vertical to the substrate 10,
whereby the metal wires 14 are made not to intercept the light so
as not to cast any shadow, and the luminous efficiency of the LED
chip 1 can be elevated.
[0107] Further, as shown in FIGS. 22a and 22b, by a provision of
recesses 33A at fillet portions to join the LED chip 1 with the
insulative adhesive or the like performed within the recesses 33A,
the short-circuiting upon the electric connection can be also
prevented from occurring.
[0108] Accordingly, by the disposition of the LED chips 1 so as to
dispose the P-type and N-type semiconductors 1a and 1b in the row
substantially vertical with the mounting surface of the substrate
10, the light emitting direction of the LED chip 1 can be rendered
substantially vertical with the substrate 10, the metal wires 14
are caused not to cast any shadow, and the LED chip can be
increased in the luminous efficiency.
[0109] In another embodiment shown in FIG. 23 of the present
invention, the luminaire comprises the substrate 10, and the LED
chips 1 disposed in respective dents 10d formed in the surface of
the substrate 10, and a through hole 10e is formed as a light
control means as penetrating through the substrate 10 at positions
where the respective dents 10d are formed.
[0110] The LED chips 1 are disposed to position the p-n junction
plane substantially vertical to the surface of the substrate 10,
and the n-type and p-type semiconductors 1a and 1b of the
respective LED chips 1 are electrically connected to the wiring
patterns (not shown) formed on the substrate 10 respectively. As
the LED chips 1 emit light in all direction in the p-n junction
plane, so that part of the emitted light of the LED chips 1 will be
radiated on the front surface side of the substrate but the rest
will be radiated to the rear surface side of the substrate 10
through the penetrating hole 10e, and the light can be radiated on
both sides of the substrate 10.
[0111] Here, a combined use of LED chips (not shown) disposed on
the front surface of the substrate 10 to position the p-n junction
plane in parallel to the surface of the substrate 10 for radiating
light emitted from the p-n junction plane on the front side as
reflected on the substrate 10, with the LED chips 1 mounted on the
substrate 10 in the orientation as shown in FIG. 23 for the
radiation of light onto both sides of the substrate 10, allows the
luminaire to radiate the light to both sides of the substrate
10.
[0112] A reflecting material is applied to the inner walls of the
penetrating holes 10e, so that the light from the LED chips 1 can
be prevented from being absorbed by the substrate 10.
[0113] Since the emission of the LED chips 1 is normally a
monochromatic light, further, it is required to mix a plurality of
luminescent colors for obtaining such white light as solar light.
Taking into account this respect, the white light is obtained in
another embodiment shown in FIGS. 24a and 24b, by utilizing the
emission of fluorescent substance and mixing the emission of the
LED chips 1 with the emission of the fluorescent substrate.
[0114] That is, a luminaire is constituted by the substrate 10, the
dents 10d formed in a surface of the substrate 10, a fluorescent
substance 25 applied to inner surface of the dents 10d, and the LED
chips 1 mounted in the respective dents 10d.
[0115] As shown in FIG. 24b, the emission spectrum P of the
fluorescent substance 25 is not identical with but rather different
from the emission spectrum O of the LED chips 1, so that, a light
which is different from the light of the LED chips 1 can be
obtained by mixing the light of the LED chips 1 with the light of
the fluorescent substance 25 with the latter applied to the
positions on the substrate 10 where the LED chips 1 are mounted,
and the white light can be obtained depending on the light of the
fluorescent substance 25. Because the LED chips 1 and the
fluorescent substance 25 are different in the emission luminance,
an optimum filter (not shown) may be provided on the surface of the
LED chips 1 for adjusting the emission luminance. Further, as an
intimate relationship is present between the emission colors of the
LED chips and fluorescent substance 25, it may suffice the purpose
of controlling the emission color of the LED luminaire as a whole
to employ the LED chips 1 which emits ultraviolet or infrared
rays.
[0116] In FIG. 25, another embodiment of the present invention is
shown, in which a metal plate 16 acting as a ground of the circuit
including the LED chips 1 is provided on rear surface (opposite
side of mounting surface) of the substrate 10, the LED chips 1 are
mounted on the metal plate 16 (of, for example, copper) at portions
exposed at the bottom of the dents 11, so as to be featured in the
arrangement where the heat generated by the LED chips 1 can be
highly efficiently radiated through the metal plate 16. Since other
respects of the arrangement are substantially the same as those of
the embodiment of FIG. 1, and their description is omitted here
with the same constituents as those in FIG. 1 denoted by the same
reference symbols in FIG. 25.
[0117] Next, manufacturing steps of the substrate 10 in the present
embodiment shall be described only for different respects from the
embodiment of FIG. 1. The metal plate 16 of a proper size and shape
is placed in a mold, and an insulative base is formed by means of
an insert injection molding. As the electrically insulating
material, polyimide, polyether imide, polyamide, liquid crystal
polymer or the like is used similar to the embodiment of FIG. 1.
The metal plate 16 may be preliminarily formed in a
three-dimensional configuration through a sheet-metal working,
machine working, chemical etching or the like.
[0118] Here, the metal plate 16 is exposed at the foregoing bottom
of the dents 11 in which the LED chips 1 are mounted, by so
disposing the metal plate 16 in the bottom simultaneously with the
molding, or by removing the molded resin by means of the laser or
honing after the molding. After alkali-degreasing the insulative
base, the metal plate 16 is subjected at its surfaces to a chemical
etching in order to activate the plate. Next, the surfaces of the
insulative base are plasma-processed to perform the surface
activation and fine surface roughening. Thereafter, similar to the
embodiment of FIG. 1, the metal layer is formed to provide the
circuit parts 12 and non-circuit parts 13, eventually the LED chips
1 are mounted in the dents 11 and are sealed by the transparent
resin, and the diffuser plate 15 is mounted to the mounting side of
the substrate 10 to complete the module of the LED luminaire.
[0119] According to the present embodiment, as has been described,
the metal plate 16 and LED chips 1 are brought into direct contact
with each other by mounting the LED chips 1 to the metal plate 16
with the metal plate 16 made as a common ground of the circuit, so
that the heat generated by the LED chips 1 can be radiated and
removed through the metal plate 16. For this reason, it is enabled
to prevent the temperature of the LED chips 1 from rising, to
prevent the luminous efficiency and luminance from being
deteriorated, and to extend the life of the LED chips 1.
[0120] In another embodiment shown in FIG. 26 of the present
invention, the luminaire is featured in that a heat emitter 16A
consisting of a metal and reflecting light is disposed around the
LED chips 1, and this heat emitter 16A of the LED chips 1 is made
to be used also as the reflector (see also FIG. 27). Since other
respects of the arrangement are substantially the same as those in
the embodiment of FIG. 1, the same constituents as those in FIG. 1
are denoted in FIGS. 26 and 27 by the same reference symbols to
omit their description.
[0121] Next, manufacturing steps of the substrate 10 in the present
embodiment shall be described only for different respects from the
embodiment of FIG. 1. The heat emitter 16A (for example, a copper
plate) of proper dimensions and configuration is placed in the mold
to form the insulative base through the insert injection molding.
For the electrically insulative material, similar to the foregoing
embodiments, polyimide, poyether imide, polyamide, liquid crystal
polymer or the like is used. The heat emitter 16A is preliminarily
formed in a three-dimensional configuration (a configuration in
which many dents 16B for mounting the LED chips 1 are disposed,
concretely) suitable as the reflector, by means of the sheet metal
working, machine working, chemical etching or the like.
[0122] After degreasing this insulative base, a chemical etching is
performed with respect to surfaces of the heat emitter 16A to
activate them. Next, the surfaces of the insulative base are
plasma-processed for their activation and fine roughening.
Thereafter, the metal layers are formed to provide the circuit
parts 12 and non-circuit parts 13, eventually the LED chips 1 are
mounted in the dents 16B of the heat emitter 16A and are sealed by
the transparent resin, and the LED luminaire module can be
completed by mounting the diffuser 15 on the mounting side of the
substrate 10.
[0123] According to the present embodiment, as has been described,
the heat emitter 16A and LED chips 1 are brought into direct
contact with each other by disposing the heat emitter 16A acting
also as the reflector around the LED chips 1, so that the heat
generated at the LED chips 1 can be removed as efficiently emitted
through the heat emitter 16A. For this reason, it is enabled to
prevent the temperature of the LED chips 1 from rising, to prevent
the luminous efficiency and luminance from being deteriorated, and
to extend the life of the LED chips 1.
[0124] In another embodiment shown in FIG. 28, the luminaire is
featured in that the MID substrate 10 is formed on one surface of a
metal plate 21 in the form of a heat emitter provided with dents
and protrusions on the surfaces, and the LED chips 1 are mounted to
the bottom and side surfaces inside each of the dents 11 formed in
the substrate 10 in conformity to the dents and protrusions of the
plate 21.
[0125] Manufacturing steps of the substrate 10 in the present
embodiment shall be briefly described next. The metal plate 21 of,
for example, copper having the dents and protrusions in its
surfaces is placed in a mold, and the substrate 10 is formed on the
plate by means of the insert injection molding. For the
electrically insulating material of the substrate, polyimide,
polyether imide, polyamide, liquid crystal or the like is employed,
likewise the embodiment of FIG. 1. The metal plate 21 is
preliminarily formed in the three-dimensional configuration having
the dents and protrusions by means of the sheet metal working,
machine working, chemical etching or the like (more concretely,
many of the dents 11 for mounting the LED chips 1 are formed).
[0126] After alkali-degreasing the above substrate molded, the
metal plate 21 chemically etched to activate its surfaces. Then,
the insulating substrate 10 is plasma-processed for surface
activation and fine roughening. Thereafter, the metal layer is
formed to provide the circuit parts 12 and non-circuit parts 13.
Eventually, the LED chips 1 are mounted within the dents 11 of the
substrate 10 and are sealed with the transparent resin, and the
diffuser 15 is mounted on the chip mounting side of the substrate
10 to complete the LED luminaire module.
[0127] According to the present embodiment as has been described,
the heat generated by the LED chips 1 can be removed as emitted
efficiently by means of the increased surface area of the metal
plate 21 by the provision of the dents and protrusions in the
surfaces, whereby the temperature of the LED chips 1 can be
prevented from rising, the luminous efficiency and luminance can be
prevented from being deteriorated, and the life of the LED chips 1
can be prolonged.
[0128] In another embodiment shown in FIG. 29 of the present
invention, the luminaire is featured in that a heat emitting fin 25
contacting at least with part of the LED chip 1 is provided. The
heat emitting fin 25 is formed by means of an aluminum die casting
and is inserted in a mold to be made integral with the substrate 10
through the insert injection molding. For the electrically
insulating material, polyimide, polyether imide, polyamide, liquid
crystal or the like is used, likewise the embodiment of FIG. 1. The
thus molded substrate is alkali-degreased, and thereafter the heat
emitting fin 25 is chemically etched at the surfaces to activate
them. Then the surfaces of the insulative substrate are
plasma-processed for their activation and fine roughening.
Thereafter, the metal layer is formed to provide the circuit parts
12 and non-circuit parts 13. Eventually, the LED chips 1 are
mounted in the respective dents 11 of the substrate 10 and are
sealed by the transparent resin, and the diffuser 15 is mounted on
the chip mounting side of the substrate 10 to complete the LED
luminaire module. Here, the LED chips 1 mounted in the dents 11 are
partly brought into contact with the heat emitting fin 25.
[0129] According to the present embodiment as has been described,
the heat generated at the LED chips 1 can be removed as emitted
efficiently through the heat emitting fin 25 since the heat
emitting fin 25 contacting with at least part of the LED chips 1 is
integrally molded with the substrate 10, whereby the temperature of
the LED chips 1 can be prevented from rising, the luminous
efficiency and luminance can be prevented from being deteriorated,
and the life of the LED chips 1 can be prolonged.
[0130] In another embodiment shown in FIG. 30 of the present
invention, many protrusions 26 are disposed lengthwise and
crosswise on one surface of the MID substrate 10, and the LED chips
1 are mounted respectively to top of each of these protrusions
26.
[0131] In manufacturing steps of the above substrate 10, such
electrically insulating material as polyimide, polyether imide,
polyamide, liquid crystal or the like is employed to form the
insulative base by means of the injection molding, and the
protrusions 26 are formed at mounting positions of the LED chips 1
while through holes 26a are formed within the protrusions 26.
[0132] After alkali-degreasing this insulative base, its surfaces
are plasma-processed to perform the surface activation and fine
roughening. Thereafter, the metal film (plating ground layer) is
formed with copper, silver, gold, nickel, platinum, palladium or
the like by means of the sputtering or vacuum evaporation on the
surface of the insulative base. Then, the metal film at the
boundary zone of the non-circuit parts 13 with respect to the
circuit parts 12 is removed by the irradiation of such
electromagnetic waves as laser or the like. Then an electric power
is supplied to the circuit parts, and the substrate 10 is obtained
in the form of a circuit substrate on which the metal film of a
predetermined thickness is formed by means of electric copper
plating, for example, with a copper sulfate plating bath.
Thereafter heat emitting pins 26b are urged into the through holes
26a formed in the protrusions 26.
[0133] The LED chips 1 are mounted respectively onto each of the
protrusions 26 of the substrate 10 thus obtained through the above
process, and the circuit parts (including the heat emitting pins
26b) and the LED chips 1 are electrically joined (die-bonding) by
means of an electrically conductive adhesive. Thereafter, the top
electrodes of the LED chips 1 and the circuit parts are joined
through metal wires (wire-bonding). By mirror-finishing peripheral
slopes of the protrusions 26 on which the LED chips 1 are mounted
so as to act also as reflector surfaces, it is possible to attain
the high luminance and high luminous efficiency. Next, the LED
chips 1 are sealed with the transparent resin, and eventually the
diffuser consisting of transparent resin or the like is mounted on
the mounting side surface of the substrate 10 to complete the LED
luminaire module of the present embodiment.
[0134] According to the present embodiment as has been described,
it is possible to remove the generated heat of the LED chips 1 as
efficiently emitted by means of the heat emitting pins 26b provided
within the substrate 10 below the LED chips 1 to be in contact with
at least part of the LED chips 1, whereby the temperature of the
LED chips 1 can be prevented from rising, the luminous efficiency
and luminance can be prevented from being deteriorated, and the
life of the LED chips 1 can be prolonged.
[0135] In another embodiment shown in FIG. 31 of the present
invention, the luminaire is featured in that a copper clad metal
element, i.e., a metal element 19 is provided on opposite side of
the MID substrate 10 to the side having many of the dents 11, an
electrically conductive layer 19a of this metal element 19 is made
to be the ground for the LED chips 1, and a chip part 19A of such
circuit elements as IC, resistors, capacitors and so on which
forming a control circuit for controlling the light emission of the
LED chips 1 is mounted on an insulative layer 19b of the metal
element 19. For other respects of this embodiment, they are
substantially the same as those in the embodiment of FIG. 1, and
their description is omitted while the same constituents as those
in FIG. 1 are denoted in FIG. 31 by the same reference symbols.
[0136] Next, the manufacturing steps of the substrate 10 of the
present embodiment shall be briefly described. First, the
insulative layer of the metal element 19 is formed in a mold
through the insert injection molding. For the electrically
insulating layer, similar to the embodiment of FIG. 1, polyimide,
polyether imide, polyamide, liquid crystal or the like is used.
After alkali-degreasing the insulative layer, its surfaces are
plasma-processed to have them activated and finely roughened.
Thereafter, the metal layer is formed to provide the circuit parts
12 and non-circuit parts 13, then the LED chips 1 are mounted on
the conductive layer 19a of the metal element 19 exposed at the
bottom of the dents 11 in the substrate 10 and are sealed with the
transparent resin.
[0137] Here, in the present embodiment, the circuit (wiring
pattern) for providing the control circuit is formed on the
insulative layer 19b of the metal element 19, after sealing by the
transparent resin the LED chips 1 mounted in the dents 11. This
pattern forming process may be either one of exposure/etching
process and laser patterning process which are general processes
for forming printed wiring board. Then, the LED luminaire module is
completed by mounting with solder the chip part 20 of such circuit
elements as the IC, resistors, capacitors and so on after forming
the circuit pattern.
[0138] According to the present embodiment, as has been described,
the metal element 19 and LED chips 1 are brought into direct
contact with each other by forming a ground with the LED chips 1
mounted to the conductive layer 19a of the copper clad metal
element 19 insert-molded on the substrate 10, so that the heat
generated by the LED chips 1 can be removed as efficiently emitted
by the metal substrate 19, whereby the temperature of the LED chips
1 can be prevented from rising, the light emitting efficiency and
luminance can be prevented from being deteriorated, and the life of
the LED chips 1 can be prolonged. Further advantage can be attained
in that the module can be minimized in size by mounting the circuit
elements of the circuit for controlling the light emission of the
LED chips 1 to the insulative layer 19b of the metal element 19,
and a shielding of the circuit chip part 20 with respect to noise
also can be achieved.
[0139] In another embodiment shown in FIG. 32 of the present
invention, the luminaire is featured in that the substrate 10
having many dents 11 in one surface is provided with ventilating
through holes 26a communicating the respective dents 11 mounting
therein the LED chips 1 with rear surface side of the substrate
10.
[0140] The through holes 26a are formed upon molding the MID
substrate 10. The following steps are the same as in the embodiment
of FIG. 1, and their description is omitted here, except that the
sealing with the synthetic resin is not performed after the
mounting of the LED chips 1 in the dents 11 of the substrate
10.
[0141] As has been referred to, in the present embodiment, it is
possible to prevent the temperature of the LED chips 1 from rising,
by causing the generated heat of the LED chips to be dispersed with
air current of convection, with the provision of the ventilating
through holes 26a communicating the dents 11 with the rear surface
side of the substrate 10, whereby the luminous efficiency and
luminance of the LED chips can be prevented from being
deteriorated, and the life of the chips also can be prolonged.
[0142] In another embodiment shown in FIGS. 33 and 34 of the
present invention, the luminaire is featured in that an MID
substrate 10B to which the LED chips 1 are three-dimensionally
mounted and a flexible substrate 10C are formed integral, and a
flexible or bendable composite substrate 10 is constituted.
[0143] Here, manufacturing steps of the substrate 10 of the present
embodiment shall be described only for different respects from the
embodiment of FIG. 1. The flexible substrate 10C made of polyimide
on which a circuit has been preliminarily formed is put in a mold,
and the flexible substrate 10C is copied on a molded article by
means of an injection molding. At portions of the molded article
where the LED chips 1 are mounted, thick parts, i.e., protrusions
43 are formed. Taking into account the bendability, the flexible
substrate 10C is left as it is at portions between the respective
thick parts 10D. The sealing with the resin is also performed only
in the vicinity of the LED chips 1, so that the sealing resin will
not be directly bent and the whole substrate will be still rendered
easily bendable. The thus molded substrate is alkali-degreased and,
thereafter, the same steps as in the embodiment of FIG. 1 are
performed to complete the substrate 10.
[0144] According to the present embodiment as has been described in
the above, it is made possible to render the substrate 10 to be
bendable and to easily vary the light distribution characteristic
by integrally forming the MID substrate 10B on which the LED chips
1 are mounted with the flexible substrate 10C and constituting the
flexible or bendable substrate 10. In addition, the luminaire can
be easily mounted to a housing or the like of the luminaire without
using any screw or the like, by utilizing the flexibility of the
substrate 10.
[0145] In another embodiment as shown in FIG. 35 of the present
invention, the luminaire is featured in that the substrate 10 in
the respective dents 11 of which a plurality of the LED chips 1 are
mounted as in the embodiment of FIG. 1 can be freely cut along line
"O" into every dimensional unit containing a predetermined number
of the LED chips 1. Basic constituents of the substrate 10 and so
on are substantially the same as those in the embodiment of FIG. 1,
and their description is omitted here by denoting the same
constituents as those in FIG. 1 with the same reference symbols in
FIG. 35.
[0146] As shown in FIG. 36, the circuit of the present embodiment
is constituted such that a predetermined number of the LED chips 1
mounted on the substrate 10 are connected in series, such series
circuits are respectively connected, through resistors R1, between
a power source line L1 and the collector of a switching element Q1,
the emitter of this switching element Q1 is connected through a
resistor R2 to a ground line L2, and the base of the switching
element Q1 is connected through resistors R3 and R4 respectively to
the power source line L1 and ground line L2. Across the power
source line L1 and ground line L2, a direct current voltage DC is
applied.
[0147] Then, the substrate 10 is made for easy cutting at proper
cutting position "O" between the respective series circuits of the
LED chips 1, so as to be a unit with required number of the LED
chips 1. Here, the number of the LED chips 1 for each unit should
correspond to an output, likewise the fluorescent lamp which is
formed with a lamp tube corresponding to the output (10, 15, 20 and
30 W), to be convenient in handling. Further, the substrate 10
should preferably be provided with grooves for rendering it to be
easily cut. Since the manufacturing steps of the substrate 10 are
the same as those in the embodiment of FIG. 1, their description is
omitted here.
[0148] According to the present embodiment as has been described,
there are brought about such advantages that the substrate 10 can
be used as cut into a dimension allowing a required intensity of
illumination to be obtained since the substrate can be freely cut
in any dimensional unit containing a predetermined number of the
LED chips 1, so as to be highly efficient, and that the substrate
10 can be manufactured at a large unit enough for decreasing
manufacturing costs.
[0149] According to the present embodiment, in particular, at least
either the dent or the protrusion is formed in a plurality and one
or a plurality of the light emitting diode element is provided with
respect to each dent or protrusion, and there are advantages that
an optional light distribution can be obtained and the luminaire
can be made thinner.
[0150] In another embodiment shown in FIG. 37 of the present
invention, the luminaire is constituted by disposing the substrate
10 to which the LED chips 1 are mounted and resin-sealed on one
side surface of a light guiding 29 made with acrylic resin into a
rectangular parallelopiped as the optical control means.
[0151] The light guiding 29 has a reflection pattern sheet 10g on
which a reflection pattern 10f is printed, as disposed on another
side surface intersecting at right angles the one side surface on
which the substrate 10 is disposed. Further, the substrate 10 is
provided as covered by a reflector plate (not shown) so that the
light from the LED chips 1 will be efficiently incident inside the
light guiding 29. The reflection pattern sheet 10g is formed by
printing the reflection pattern 10f with white color for performing
an optional distribution of light, while the reflection pattern 10f
of circular marks will be coarse on the side closer to the
substrate 10 but dense on the side separated from the substrate
10.
[0152] Accordingly, the light emitted from the LED chips 1 is made
incident into the light guiding 29 and, through multiple reflection
on the reflection pattern 10f and so on, radiated out of the side
surface opposing the reflection pattern sheet 10g, as shown by
arrows. Here, as the light is caused to perform the multiple
reflection inside the light guiding 29 to be of uniform
distribution of luminance, and it is enabled to prevent any
non-uniform luminance of the LED chip 1 from occurring.
[0153] The reflection pattern 10f may even be directly printed on
the surface of the light guiding 29 or may be replaced by any other
means than the printing, such as a grooving work or the like,
suitable for an irregular reflection. In this case, the light is
radiated out of both side surface of the light guiding 29, and the
emission efficiency can be improved.
[0154] Further, the light guiding 29 may also be formed integral
with the substrate 10 by means of the sealing resin for sealing the
surface of the substrate 10. Further, while the LED chips 1 may be
monochromatic, it is possible to employ a plurality of types of the
LED chips 1 different in the luminous color, in which event the
light blending is easier and an optional color of light can be
obtained.
[0155] In the present embodiment as in the above, the light
distribution control can be attained by the light guiding 29 per
se, so that an image of the light source disappears, it is made
unnecessary for the color blending to control the emitted light of
the respective LED chips one by one, and there arises an advantage
that any other optical control means than the light guiding 29 can
be omitted.
[0156] In another embodiment shown in FIG. 38 of the present
invention, the optical control means is made movable in contrast to
the foregoing optical control means disposed stationary in the
embodiments of FIGS. 33-37. That is, the LED luminaire 30 is
constituted with the substrate 10, LED chips 1R, 1G and 1B of red,
green and blue and disposed in each dent 11b formed in the
substrate 10, molded layer 10A for the sealing, prism lens plate
27c acting as a stationary optical control means for the light
distribution control, and further prism lens plate 27d of the same
configuration and disposed rotatable in a plane parallel with the
substrate 10 and in front of the stationary prism lens plate
27c.
[0157] With the further prism lens plate 27d rotated, it is
possible to control the distribution of light as a whole of the LED
chips 1R, 1G and 1B arranged on the substrate 10, to have the state
of color blending varied. At this time, the LED chips 1 may be
monochromatic.
[0158] Further, while in the embodiment of FIG. 38 only one of the
two prism lens plates 27c and 27d is made rotatable, it is possible
to dispose both of them rotatable. Further, it is also possible to
form the optical control means with a single movable prism lens
plate.
[0159] In another embodiment shown in FIG. 39 of the present
invention, the luminaire is so formed that the substrate 10 is
provided with a plurality of parallel rows of sloped side surfaces
10a of the protrusions substantially of a right angled triangle in
section, the LED chips 1 are disposed on sloped side surface of the
respective sloped side faces 10a to control the distribution of
light of the LED chips 1 at the stage of their mounting, and
microlens plate 27 is disposed rotatable in the plane parallel to
the substrate 10 in front of the LED chips, the lens being thus
single here.
[0160] Thus, in the present embodiment, at least one of the movable
optical control means such as the prism lens plate 27c is employed,
so that the distribution of light can be optionally varied by
actuating the optical control means, and the user is allowed to
easily perform the light distribution control desired at installed
position of the luminaire. Therefore, the illumination appliance
incorporating this LED luminaire 30 is not required to be changed
in its direction when the distribution of light is modified.
[0161] In another embodiment shown in FIG. 40 of the present
invention, the luminaire is formed for controlling also the
direction of the light distribution, by controlling the mounting
direction of the LED chips 1 by means of the substrate 10 which
comprises an MID substrate which is moldable into the three
dimensional configuration, whereby a precise light distribution
control is enabled as combined with such optical control means as
the prism lens plate 27.
[0162] In the above, the resin material for use as the MID
substrate may be any resin material, while such one desirably
excellent in the electrical properties or in heat emission
properties as the liquid crystal polymer is employed in the present
embodiment. Further, the substrate is formed in the
three-dimensional configuration having the protrusions of the right
angled triangle in section similar to the embodiment of FIG. 38, so
as to be able to mount the LED chips 1 in the direction of light
distribution, and the sloped side surface 10a of such protrusion is
used as the mounting surface.
[0163] According to the present invention as has been described,
generally, the substrate is provided with at least either of the
dents and protrusions, and one or a plurality of the LED chip or
chips is disposed with respect to each of the dents or protrusions,
so that the optional distribution of light can be easily attained
and the luminaire can be thinned, as will be readily
appreciated.
* * * * *