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Description  |
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BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to an elements aligning/coupling apparatus
and method for aligning and coupling a coupling part including a lens, for
example, with a light receiving element, a light emitting element, or the
like used in the optical communication.
Discussion of the Prior Art
A conventional elements aligning/coupling apparatus is illustrated in FIGS.
33 and 34.
As shown in FIGS. 33 and 34, a light receiving or emitting element
(referred to simply as an optical element) 11 is located on an element
holder 101. The element holder 101 is mounted on an apparatus body 103
with legs 102. The apparatus body 103 is supported by an X-stage 104 and a
Y-stage 105. The X-stage 104 is movable in an X-direction, while the
Y-stage 105 is movable in a Y-direction orthogonal to the X-direction. A
lead pin 12 of the optical element 11 is inserted into a socket 106
mounted on the lower side of the apparatus body 103.
An optical fiber 14 is connected to a coupling part 13 that is placed
facing the optical element 11, and is supported by a support arm 107. The
support arm 107 is mounted on a Z-stage 108, which is movable in a
Z-direction orthogonal to the X- and Y-directions.
To start the aligning work of the optical element 11 with coupling part 13,
the Z-stage 108 moves the coupling part 13 in the Z-direction with respect
to the optical element 11 firmly supported, so that the coupling end face
of the coupling part comes in close contact with the coupling end face of
the optical element 11. Under this condition, the optical element 11 is
moved in the X- and Y-directions by the X-stage 104 and the Y-stage 105.
FIG. 35 is a plan view showing another conventional elements
aligning/coupling apparatus. FIGS. 36 and 37 are cross sectional views of
key portions of the apparatus.
As shown in FIGS. 35 through 37, the elements aligning/coupling apparatus
pushes down a coupling part that is held by a chuck against an optical
element firmly supported, whereby the coupling end faces of the coupling
part comes in close contact with the coupling end face of the optical
element.
A holder 111, vertically movable, has a support hole 112 in the central
portion thereof. A float 113 is vertically movably placed within the
support hole 112. Three hooks 114, equidistantly disposed as viewed in the
circumferential direction, are radially movably supported on the float
113. A pin 116 of each hook 114 interlocks with each cam groove 115 of the
float 113. Three support pins 117 are planted in the float 113. Each
support pin 117 are inserted into each support hole 119 of a bracket 118
secured to the holder 111. A coiled spring 120 intervenes between the
support pins 117 and the support hole 119. Reference numeral 121
designates a stopper for stopping the movement of the float 113, and
numeral 122 indicates a spring-contained pin for removing a play of the
hook 114 that is caused by presence of a gap.
The float 113 is provided with a chuck handle 123, while the holder 111 is
provided with a lock handle 124 for locking the chuck handle 123.
To hold a coupling part 125, the hooks 114 move outwardly, and then the
coupling part 125 is placed at the central portion of the float 113. Then,
the float 113 is turned counterclockwise (as viewed in FIG. 35) by the
chuck handle 123. With the cam groove 115, the hooks 114 are moved
inwardly to hold the coupling part 125 with the fore ends of the hooks.
Under this condition, the chuck handle 123 is locked by the lock handle
124. Then, the holder 111 is moved downwardly while the coupling part 125
is held, so that the coupling end face of the coupling part is brought
into close contact with the coupling end face of the optical element (not
shown).
In the conventional elements aligning/coupling apparatuses as stated above,
the coupling end face of the coupling part is brought into close contact
with the coupling end face of the optical element in a manner that the
coupling part is axially moved toward the optical element firmly
supported. The parallelism between the coupling end faces of the optical
element and the coupling part depends on how the optical element is
supported and hew the coupling part is held. When the parallelism between
them is lost, the optical element 11 is tilted with respect to the
coupling part 13, to produce a gap S between the coupling end faces
thereof, as shown in FIG. 38. The element 11 and the part 13 thus coupled
having the gap S therebetween are fixedly connected by welding, and then
is subjected to a resin mold forming process. In the forming process, the
gap S is filled with resin. The resultant coupled component exhibits an
abnormal coupling performance.
In a case that the optical element 11 is, for example, a light emitting
diode (LED) with the lead pin that is bent in its manufacturing stage,
when the LED is brought into close contact with the coupling part, a gap S
is produced between the coupling end faces thereof both facing each other,
as in the above case. As seen also from FIG. 39 of a histogram, the
coupled components had relatively large gaps, and its average value was
30.7 .mu.m.
The parallelism (gap) between the coupling end faces being in close contact
with each other is an essential matter in gaining a required part
accuracy- One of the possible approaches to gain the desired parallelism
is to adjust an inclination angle of the coupling part with respect to the
optical element when they are coupled. However, this approach requires a
complicated construction, which leads to increase of cost to manufacture.
The inclination angle adjustment is time- consuming. As a result, the
production efficiency is decreased. The bent-lead problem of the LEDs may
be solved by straightening the bent lead pins before its aligning work.
However, the straightening work also takes much time and is troublesome.
SUMMARY OF THE INVENTION
Accordingly, the present invention has been made in view of the above
circumstances and has an object to provide an elements aligning/coupling
apparatus which can more efficiently align and couple an optical element
with a coupling part by providing a reliable, close contact of them.
According to a first aspect of the present invention, there is provided an
elements aligning/coupling apparatus of the type in which a coupling part
is brought into close contact with an optical element held by an element
holder, in which a plate-like resilient member is disposed around the
element holder, a plurality of first coupling parts of the resilient
member are secured to the element holder and a plurality of second
coupling parts of the resilient member are secured to the apparatus body.
In the elements aligning/coupling apparatus, the resilient member is a disk
spring, the disk spring is fastened to the element holder at two points
thereof that lie on a circle coaxial with the disk spring and on a first
line that radially extends, and further to the apparatus body at two
points thereof that lie on a circle coaxial with the disk spring and on a
second line that radially extends.
Also in the elements aligning/coupling apparatus, slits are formed in the
disk spring in such a fashion that each slit radially extending is located
between the fixing points.
Alternatively, slits are formed in the disk spring in such a fashion that
each slit is located between the fixing points, and each slit extends from
the outer side of the spring toward the inner side thereof, and the inner
side of each slit extends along the inner circumference thereof.
According to a second aspect of the present invention, there is provided an
elements aligning/coupling apparatus, in which the resilient member is a
disk spring, three first fixing points are formed at such positions of the
disk spring that are substantially equidistantly separated as viewed in
the circumferential direction and lie on a circle coaxial with the disk
spring, and three second fixing points are formed at such positions of the
disk spring that are substantially equidistantly separated as viewed in
the circumferential direction and lie on a circle coaxial with the disk
spring, the second fixing points each being located between the adjacent
two first fixing points.
Even in such a situation where those elements are coupled in a state of
poor parallelism between their coupling end faces, when those elements are
made to press contact with each other, the optical element is tilted
against the coupling end face of the coupling part, because the optical
element mounted on the element holder is resiliently supported by the
resilient member provide between the holder and the apparatus body.
Accordingly, the resultant coupled component has no gap between the
coupling end faces of them.
In the elements aligning/coupling apparatus, the resilient member is a disk
spring. The disk spring is fastened to the element holder at two points
thereof that lie on the first line, and further to the apparatus body at
two points thereof that lie on the second line. Sleeves are formed in the
disk spring in such a fashion that each sleeve radially extending is
located between the fixing points, and the inner side of each sleeve
extends along the inner circumference thereof. The disk spring, when
receiving an external force, is deformed with short distance from the
fulcrum. Therefore, it can be deformed with weak force applied thereto.
The optical element is flexibly tiltable against the coupling part. Three
first fixing points are formed at locations of the disk spring
substantially equidistantly separated, and three second fixing points are
formed at locations of the disk spring substantially equidistantly
separated, the second fixing points each being located between the
adjacent two first fixing points.
According to a third aspect of the invention, there is provided an elements
aligning/coupling apparatus of the type in which a coupling part is
brought into close contact with an optical element held by an element
holder, in which the coupling end face of the element holder is tiltably
and resiliently supported by means of plate springs radially extending
from the outer circumference of the element holder.
With the above arrangement, even in such a situation where those elements
are coupled in a state of poor parallelism between their coupling end
faces, when those elements are made to press contact with each other, the
optical element mounted on the element holder is tilted against the
coupling end face of the coupling part, with the aid of the radially
extending plate springs. Accordingly, the resultant coupled component has
no gap between the coupling end faces of them.
According to a fourth aspect of the present invention, there is provided an
elements aligning/coupling apparatus of the type in which a coupling part
is brought into close contact with an optical element held by an element
holder, in which the coupling end face of the element holder is tiltably
and resiliently supported by means of bar-like members radially extending
from the outer circumference of the element holder.
With the above arrangement, even in such a situation where those elements
are coupled in a state of poor parallelism between their coupling end
faces, when those elements are made to press contact with each other, the
optical element mounted on the element holder is tilted against the
coupling end face of the coupling part, with the aid of the radially
extending bar-like members. Accordingly, the resultant coupled component
has no gap between the coupling end faces of them.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part
of this specification illustrate, embodiments of the invention and,
together with the description, serve to explain the objects, advantages
and principles of the invention. In the drawings,
FIG. 1 is a perspective view showing an element holder used in an elements
aligning/coupling apparatus according to a first embodiment of the present
invention;
FIG. 2 is a cross sectional view taken on line II--II in FIG. 1;
FIG. 3 is a cross sectional view taken on line III--III in FIG. 1;
FIG. 4(a) is a plan view showing a disk spring coupled with the element
holder of FIG. 1;
FIG. 4(b) is a cross sectional view showing the disk spring of FIG. 4(a);
FIG. 5 is a perspective view showing an elements aligning/coupling
apparatus according to the first embodiment of the present invention;
FIG. 6 is a front view showing the elements aligning/coupling apparatus;
FIG. 7 is a flowchart showing sequences of procedural steps to manufacture
the optical link which was light emitting and receiving elements;
FIGS. 8(a) through 8(c) are perspective views showing sequential steps of
manufacturing the optical link which uses light emitting and receiving
elements;
FIGS. 9(a) through 9(d) are partial, cross sectional views showing a
sequence of steps of aligning and coupling an optical element with a
coupling part;
FIG. 10 is a graph showing a histogram in which the relationship between
the number of element-part coupled components and their gaps are plotted;
FIG. 11 is a graph showing variations of the times taken for the aligning
and coupling work with respective to the respective pieces of that work;
FIG. 12 is a perspective view showing an element holder used in an elements
aligning/coupling apparatus according to a second embodiment of the
present invention;
FIG. 13 is a cross sectional view taken on line XIII--XIII in FIG. 12;
FIG. 14 is a cross sectional view taken on line XIV--XIV in FIG. 12;
FIG. 15(a) is a plan view showing a disk spring coupled with the element
holder of FIG. 12;
FIG. 15(b) is a cross sectional view showing the disk spring of FIG. 15(a);
FIG. 16 is a graph showing a histogram in which the relationship between
the number of element-part coupled components and their gaps are plotted;
FIG. 17 is a perspective view showing an element holder used in an elements
aligning/coupling apparatus according to a third embodiment of the present
invention;
FIG. 18 is a cross sectional view taken on line XVIII--XVIII in FIG. 17;
FIG. 19 is a cross sectional view taken on line XIX--XIX in FIG. 17;
FIG. 20(a) is a plan view showing a disk spring coupled with the element
holder of FIG. 17;
FIG. 20(b) is a cross sectional view showing the disk spring of FIG. 20(a);
FIG. 21 is a perspective view showing an element holder used in an elements
aligning/coupling apparatus according to a fourth embodiment of the
present invention;
FIG. 22 is a perspective view showing an element holder used in an elements
aligning/coupling apparatus according to a fifth embodiment of the present
invention;
FIG. 23 is a perspective view showing an element holder used in an elements
aligning/coupling apparatus according to a sixth embodiment of the present
invention;
FIG. 24 is a cross sectional view taken on line XXIV--XXIV in FIG. 23;
FIG. 25(a) is a plan view showing a disk spring coupled with the element
holder of FIG. 23;
FIG. 25(b) is a cross sectional view showing the disk spring of FIG. 25(a);
FIG. 26 is a perspective view showing an element holder used in an elements
aligning/coupling apparatus according to a seventh embodiment of the
present invention;
FIG. 27 is a longitudinal sectional view of the elements aligning/coupling
apparatus of FIG. 26;
FIG. 28 is a graph showing a histogram in which the relationship between
the number of element-part coupled components and their gaps are plotted;
FIG. 29 is a perspective view showing an element holder used in an elements
aligning/coupling apparatus according to an eighth embodiment of the
present invention;
FIG. 30 is a longitudinal sectional view of the elements aligning/coupling
apparatus of FIG. 29;
FIG. 31 is a cross sectional view showing a support structure with a
different support pin;
FIG. 32 is a graph showing a histogram in which the relationship between
the number of element-part coupled components and their gaps are plotted;
FIG. 33 is a perspective view showing a conventional element holder used in
an elements aligning/coupling apparatus;
FIG. 34 is a side view showing the elements aligning/coupling apparatus of
FIG. 33;
FIG. 35 is a plan view showing another conventional elements
aligning/coupling apparatus;
FIG. 36 is a cross sectional view taken on line XXXVI--XXXVI in FIG. 35;
FIG. 37 is a cross sectional view taken on line XXXVII--XXXVII in FIG. 35;
FIG. 38 is a side view showing a gap produced in an element-part coupled
component; and
FIG. 39 is a graph showing a histogram in which the relationship between
the number of element-part coupled components and their gaps are plotted.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Detailed description of the preferred embodiments of the present invention
will be described with reference to the accompanying drawings. Throughout
the drawings, like reference numerals and characters will be used for
designating like or equivalent portions, for simplicity and clarity.
An elements aligning/coupling apparatus according to a first embodiment of
the present invention will be described with reference to FIGS. 1 through
11.
FIG. 1 is a perspective view showing an element holder used in an elements
aligning/coupling apparatus according to a first embodiment of the present
invention. FIG. 2 is a cross sectional view taken on line II--II in FIG.
1. FIG. 3 is a cross sectional view taken on line III--III in FIG. 1. FIG.
4(a) is a plan view showing a disk spring coupled with the element holder
of FIG. 1. FIG. 4(b) is a cross sectional view showing the disk spring of
FIG. 4(a). FIG. 5 is a perspective view showing an elements
aligning/coupling apparatus according to the first embodiment of the
present invention. FIG. 6 is a front view showing the elements
aligning/coupling apparatus. FIG. 7 is a flowchart showing sequences of
procedural steps to manufacture light emitting and receiving elements.
FIGS. 8(a) through 8(c) are perspective views showing sequential steps of
manufacturing light emitting and receiving elements. FIGS. 9(a) through
9(d) are partial, cross sectional views showing a sequence of steps of
aligning and coupling an optical element with a coupling part. FIG. 10 is
a graph showing a histogram in which the number of element-part coupled
components (where optical element are aligned and coupled with coupling
parts) vs. gaps produced therein are plotted. FIG. 11 is a graph showing
variations of the times of the aligning and coupling work with respective
to the respective pieces of the work.
In the elements aligning/coupling apparatus of the first embodiment, as
shown in FIGS. 1 through 3, an element holder 21, cylindrical in shape,
has two through-holes 22 into which lead pins 12 of an optical element 11
are inserted. Accordingly, the optical element 11 can be mounted on the
top of the element holder 21. The element holder 21 is fastened at the
bottom to the central portion of a disk-like holder 23. Cut-out portions
24, disposed radially opposed to each other, are formed in the
circumferential outer side of the holder 23. A disk spring 26, which
intervenes between the element holder 21 and support poles 25 and 25,
resiliently supports the element holder 21 against the support poles 25.
As shown in FIGS. 4(a) and 4(b), the disk spring 26 has a hole 27 in the
central part thereof. A pair of mounting holes 28, formed also in the disk
spring 26, are disposed on a first X line extending radially and including
the center 0 and symmetrically with respect to the center 0. Another pair
of mounting holes 29 are also formed therein being disposed on a second Y
line, which extends radially, includes the center 0, and substantially
orthogonal to the first X line, and are symmetrical with respect to the
center 0. The disk spring 26 is secured to the holder 23 of the element
holder 21 by inserting fixing pins 30 into the mounting holes 28 as shown
in FIG. 2, and is secured to the upper ends of the support poles 25 of the
apparatus body by inserting fixing pins 31 into the mounting holes 29 as
shown in FIG. 3.
Thus, the element holder 21 is coupled resiliently, by means of the disk
spring 26, with two support poles 25 of the apparatus body through the
holder 23. The coupling end face of the optical element 11, which is
mounted on the element holder 21, is tiltable against the coupling end
face of a coupling part, not shown. The disk spring 26 may be made of
metal, such as phosphorus bronze and stainless, or synthetic resin.
The element holder 21 for supporting the optical element 11 is movable in
the horizontal direction, and a coupling part 13 coupled with an optical
fiber 14 is movable in the vertical direction. As shown in FIG. 5, the two
support poles 25 are supported by an X-stage 32 and a Y-stage 33. The
X-stage 32 is horizontally movable in the X-direction. The Y-stage 33 is
horizontally movable in the Y-direction orthogonal to the X-direction. The
coupling part 13, which is located facing the optical element 11, is
supported by a support arm 34. The support arm 34 is mounted on an Z-stage
35, which is movable in the Z-direction orthogonal to the X- and
Y-directions.
The optical element 11 is positioned and held in a state that it is mounted
on the element holder 21. As shown in FIG. 6, a bracket 37 is secured to
the left (FIG. 6) end part of the lower side of the holder 23 by means of
a bolt 36. An electrode plate 39 is also secured to the bracket 37 by
means of a bolt 38. A lead wire, not shown, is connected to the electrode
plate 39. A support bracket 41 is secured to the right end part (FIG. 6)
of the lower side of the holder 23 by means of a bolt 40. The lower part
of the support bracket 41 is Y-shaped into which an operation lever 42 is
rotatably coupled by means of a pin 43. A hand grip is formed around the
base portion of the operation lever 42. A clamp plate 44 coated with
rubber is secured to the fore end of the operation lever 42. The lead pins
12 of the optical element 11 is nipped by the clamp plate (rubber) 44 and
the electrode plate 39. The operation lever 42 is kept horizontally while
holding the lead pin 12 of the optical element 11 when a metal piece 45 is
magnetically attracted to a magnet 46 secured to the holder 23.
The elements aligning/coupling apparatus of the present embodiment is used
in the manufacturing stage of light emitting and receiving elements for
optical communication. The manufacturing process of an optical link will
be described. As shown in FIGS. 7 and 8, semiconductor chips, for example,
are bonded to a lead frame 47, thereby to assembly a substrate 48. Then,
an E/O (electrooptic) transducing element 49 and an O/E (optoelectric)
transducing element 50 are respectively aligned with the coupling parts
and coupled with them by welding. Then, those are inspected. Then, as
shown in FIG. 8(a), the E/O transducing element 49 is coupled with the
substrate 48, and the O/E transducing element 50 is coupled with the
substrate. As shown in FIG. 8(b), the resultant assembly is molded by
resin, thereby forming a molded product 51. Finally, as shown in FIG.
8(c), a receptacle 52 is attached to the product, and the resultant
product is inspected.
How to align and couple the E/O and the O/E transducing elements with
coupling parts by using the elements aligning/coupling apparatus of the
first embodiment will be described. The aligning and coupling work of an
E/O transducing element with a coupling part will first be described. A
light emitting element 11 as an optical element is mounted on the element
holder 21 by inserting the lead pins 12 of the optical element into the
through-holes 22 of the holder (FIGS. 1, 5, and 6). The lead pins 12 of
the optical element 11 are nipped by the electrode plate 39 and the clamp
plate (rubber) 44 by turning the operation lever 42 to be horizontal. A
sleeve 13 with a lens 13a as a coupling part is set to the support arm 34
of the Z-stage 35. Then, the support arm 34 is moved in the Z-direction,
so that the sleeve 13 is made to approach to the light emitting element
11, and the end faces of those elements are brought into close contact
with each other. In this way, the optical element is aligned with the
coupling part.
To be more specific, the sleeve 13 is made to approach to the light
emitting element 11 mounted on the element holder 21 (see FIG. 9(a)),
whereby the coupling end face of the sleeve 13 is brought into press
contact with the coupling end face of the light emitting element 11. Here,
the close contact of the end faces of both the elements is secured. In
this case, if the parallelism between the coupling end faces of those
elements is poor, the exact parallelism will automatically be set up
because of the unique construction of the first embodiment. As recalled,
the element holder 21 is resiliently supported by the disk spring 26,
which is supported by the support poles 25 and the holder 23. Therefore,
in this situation where those elements are coupled in a state of poor
parallelism between their coupling end faces, the disk spring 26 is
deformed with respect to the X line and Y line so that the light emitting
element 11 mounted on the element holder 21 comes in close contact with
the sleeve 13 in a state of good parallelism of their coupling end faces.
The light emitting element 11 is aligned with the lens 13a in a manner that
the optical fiber 14 is inserted into the sleeve 13 from its top and
current is fed thereto, and the light emitting element 11 is moved for
adjustment in the X-direction and Y-direction (see FIG. 9(b)). After the
aligning work, three-spot laser beams are applied to the connection part
of the light emitting element 11 and the sleeve 13, thereby to weld there
(see FIG. 9(c)). The E/O transducing element, after the diode 11 and the
sleeve 13 are aligned and coupled by welding, is removed from the element
holder 21 (see FIG. 9(d)). In the case of an O/E transducing element for
the optical element, a photo diode (PD), in place of the light emitting
diode, is set to the element holder, and is subjected to the same aligning
process while light is applied through the optical fiber, and coupled by
welding.
Gap between the optical element (light emitting diode) 11 and the coupling
part (sleeve) 13 of each of the thus coupled components were measured and
graphically represented in a histogram as shown in FIG. 10. As seen, no
large gap S was observed. The only gaps S observed were small, with an
average value of 4.3 .mu.m. The time of the work of aligning and coupling
the optical element with the coupling part was measured for the respective
pieces of the work, and plotted into a graph of FIG. 11. As seen from the
figure, the times for the respective work pieces were remarkably reduced
when comparing with those by the conventional elements aligning/coupling
apparatus. The time by the apparatus of the invention was 27.3% of that by
the conventional apparatus.
An elements aligning/coupling apparatus according to a second embodiment of
the present invention will be described with reference to FIGS. 12 through
16.
FIG. 12 is a perspective view showing an element holder used in an elements
aligning/coupling apparatus according to a second embodiment of the
present invention. FIG. 13 is a cross sectional view taken on line
XIII--XIII in FIG. 12. FIG. 14 is a cross sectional view taken on line
XIV--XIV in FIG. 12. FIG. 15(a) is a plan view showing a disk spring used
in the apparatus. FIG. 15(b) is a cross sectional view showing the disk
spring of FIG. 15(a). FIG. 16 is a graph showing a histogram in which the
relationship between the number of element-part coupled components and
their gaps are plotted.
As shown in FIGS. 12 through 14, in the elements aligning/coupling
apparatus of the second embodiment, the element holder 21 is resiliently
coupled with the support poles 25 by means of a disk spring 55, which
intervenes between the element holder 21 and the support poles 25. As
shown in FIG. 15, the disk spring 55 has a hole 27 in the central part
thereof. A pair of mounting holes 28, formed also in the disk spring 55,
are disposed on a first X line extending radially. Another pair of
mounting holes 29 are also formed therein being disposed on a second Y
line, which extends radially and is substantially orthogonal to the first
X line. The disk spring 55 is fastened to the holder 23 of the element
holder 21 by inserting fixing pins 30 into the mounting holes 28 as shown
in FIG. 13, and is fastened to the upper ends of the support poles 25 of
the apparatus body by inserting fixing pins 31 into the mounting holes 29,
as shown in FIG. 14.
A pair of slits 56 and 56 are formed on both sides of each of the two
fixing points (mounting holes 28 and the fixing pins 30), which lie on the
X line. Another pair of slits 57 and 57 are formed on both sides of each
of the two fixing points (mounting holes 29 and the fixing pins 31), which
lie on the Y line. Thus, the element holder 21 is coupled resiliently, by
means of the disk spring 55, with two support poles 25 of the apparatus
body through the holder 23. The coupling end face of the optical element
11, which is mounted on the element holder 21, is tiltable against the
coupling end face of a coupling part.
To align and couple an optical element 11 with a coupling part, the
coupling part is pushed against the optical element 11 held by the element
holder 21, thereby to bring the coupling end face of the coupling part
into close contact with the coupling end face of the optical element 11.
In this case, if the parallelism between the coupling end faces of those
elements is poor, the exact parallelism will automatically be set up
because of the unique construction of the second embodiment. As recalled,
the element holder 21 is resiliently supported by the disk spring 55,
which is supported by the support poles 25 and the holder 23. Therefore,
in such a situation where those elements are coupled in a state of poor
parallelism between their coupling end faces, when the optical element is
pressed against the coupling part, the optical element 11 on the element
holder 21 is tilted so that the element 11 is brought into close contact
with the coupling part over their coupling end faces. Accordingly, the
resultant coupled component has no gap between the coupling end faces of
them.
It is noted here that the disk spring 55 has the paired slits 56, which are
provided on both sides of each of the two fixing points on the X line, and
further the paired slits 57 likewise, which are provided on both sides of
each of the two fixing points on the Y line. With the paired slits 56 and
57, the disk spring 55 can be deformed with weak force applied thereto for
the X and Y lines. Therefore, the element holder 21 more sensitively and
flexibly responds to the force applied thereto, so that the optical
element 11 mounted thereon is sensitively tilted to come in contact with
the coupling part over the entire end faces thereof, without any gap
formed therebetween.
Gap between the optical element 11 and the coupling part of each of the
thus coupled components were measured and plotted into a histogram as
shown in FIG. 16. As seen, no large gap S was not observed. The only gaps
S observed were small and had an average value of 3.6 .mu.m.
An elements aligning/coupling apparatus according to a third embodiment of
the present invention will be described with reference to FIGS. 17 through
20.
FIG. 17 is a perspective view showing an element holder used in an elements
aligning/coupling apparatus according to a third embodiment of the present
invention. FIG. 18 is a cross sectional view taken on line XVIII--XVIII in
FIG. 17. FIG. 19 is a cross sectional view taken on line XIX--XIX in FIG.
17. FIG. 20(a) is a plan view showing a disk spring coupled with the
element holder of FIG. 17. FIG. 20(b) is a cross sectional view showing
the disk spring of FIG. 20(a).
As shown in FIGS. 17 through 19, in the elements aligning/coupling
apparatus of the third embodiment, the element holder 21 is resiliently
coupled with the support poles 25 by means of a disk spring 61, which
intervenes between the element holder 21 and the support poles 25. As
shown in FIG. 20, the disk spring 61 has a hole 27 in the central part
thereof. A pair of mounting holes 28, formed also in the disk spring 61,
are disposed on a first X line extending radially. Another pair of
mounting holes 29 are also formed therein being disposed on a second Y
line, which extends radially and is substantially orthogonal to the first
X line. The disk spring 61 is fastened to the holder 23 of the element
holder 21 by inserting fixing pins 30 into the mounting holes 28 as shown
in FIG. 18, and is fastened to the upper ends of the support poles 25 of
the apparatus body by inserting fixing pins 31 into the mounting holes 29,
as shown in FIG. 19.
A pair of slits 62 and 62 are formed on both sides of each of the two
fixing points (mounting holes 28 and the fixing pins 30), which lie on the
X line. Another pair of slits 63 and 63 are formed on both sides of each
of the two fixing points (mounting holes 29 and the fixing pins 31), which
lie on the Y line. Each of the paired slits 62 and 63 includes a linear
part 64 and an arc part 65. The linear parts 64 of the paired slits 62
(63), located on both sides of each fixing point (mounting hole 28 (29)
and fixing pin 30 (31)), are parallel to each other. The arc parts 65 of
the paired slits 62 (63) extend along the circumference of the hole 27 but
in the directions opposite to each other. Thus, the element holder 21 is
coupled resiliently, by means of the disk spring 61, with two support
poles 25 of the apparatus body through the holder 23. The coupling end
face of the optical element 11, which is mounted on the element holder 21,
is tiltable against the coupling end face of a coupling part.
To align and couple an optical element 11 with a coupling part, the
coupling part is pushed against the optical element 11 held by the element
holder 21, thereby to bring the coupling end face of the coupling part
into close contact with the coupling end face of the optical element 11.
In this case, if the parallelism between the coupling end faces of those
elements is poor, the exact parallelism will automatically be set up
because of the unique construction of the third embodiment. As recalled,
the element holder 21 is resiliently supported by the disk spring 61,
which is supported by the support poles 25 and the holder 23. Therefore,
in such a situation where those elements are coupled in a state of poor
parallelism between their coupling end faces, when the optical element is
pressed against the coupling part, the optical element 11 on the element
holder 21 is tilted so that the element 11 is brought into close contact
with the coupling part over their coupling end faces. Accordingly, the
resultant coupled component has no gap between the coupling end faces of
them.
It is noted here that the disk spring 61 has the paired slits 62 and 63,
which are provided on both sides of each of the two fixing points on the X
line, and further the paired slits 63 likewise, which are provided on both
sides of each of the two fixing points on the Y line, and each of those
slits includes the linear part 64 and arc part 65. With the paired slits
62 and 63 thus shaped, the disk spring 61 is tiltable in any direction.
The disk spring 61, when receiving an external force, is deformed with
short distance from the fulcrum. Therefore, it can be deformed with weak
force applied thereto for the X and Y lines. The element holder 21 more
sensitively and flexibly responds to the force applied thereto, so that
the optical element 11 mounted thereon is sensitively tilted to come in
contact with the coupling part over the entire end faces thereof, without
any gap formed therebetween.
Gap between the optical element 11 and the coupling part of each of the
thus coupled components were measured. The measurement results showed no
large gap S was not observed. Gaps S observed were small and their average
value was 3.2 .mu.m.
FIG. 21 is a perspective view showing an element holder used in an elements
aligning/coupling apparatus according to a fourth embodiment of the
present invention.
As shown in FIG. 21, in the elements aligning/coupling apparatus of the
fourth embodiment, the element holder 21 is resiliently coupled with the
support poles 25 by means of a disk spring 66, which intervenes between
the element holder 21 and the support poles 25. As shown, the disk spring
66 has a hole 27 in the central part thereof. Two couples of support
members 67 and 68, disposed orthogonal to each other, extend radially and
outwardly from a ring-like disk spring 66 located around the upper part of
the element holder 21. The spring 66 is fastened to the holder 23 by means
of fixing pins 30 at two fixing points on the first X line and further to
the top ends of the support poles 25 of the apparatus by means of
additional fixing pins 31 at two additional fixing points on the second Y
line. Accordingly, the element holder 21 is resiliently connected, by
means of the spring 66, to the two support poles 25 of the apparatus
through the holder 23. The optical element 11 set to the element holder 21
is tiltable against the coupling end face of the coupling part.
To align and couple an optical element 11 with a coupling part, the
coupling part is pushed against the optical element 11 held by the element
holder 21, thereby to bring the coupling end face of the coupling part
into close contact with the coupling end face of the optical element 11.
In this case, if the parallelism between the coupling end faces of those
elements is poor, the exact parallelism will automatically be set up
because of the unique construction of the fourth embodiment. As recalled,
the element holder 21 is resiliently supported by the spring 66, which is
supported by the support poles 25 and the holder 23. Therefore, in such a
situation where those elements are coupled in a state of poor parallelism
between their coupling end faces, when the optical element is pressed
against the coupling part, the optical element 11 on the element holder 21
is tilted so that the element 11 is brought into close contact with the
coupling part over their coupling end faces. Accordingly, the resultant
coupled component has no gap between the coupling end faces of them.
FIG. 22 is a perspective view showing an element holder used in an elements
aligning/coupling apparatus according to a fifth embodiment of the present
invention.
As shown in FIG. 22, in the elements aligning/coupling apparatus of the
third embodiment, the element holder 21 is resiliently coupled with the
support poles 25 by means of a disk spring 71, which intervenes between
the element holder 21 and the support poles 25. As shown, the disk spring
71 has a hole 27 in the central part thereof. The disk spring 71 has a
couple of mounting holes 28 formed therein and disposed on a first X line
that radially extends, and another couple of mounting holes 29 disposed on
a second Y line that is radially extends and is orthogonal to the first X
line. The spring 71 is fastened to the holder 23 of the element holder 21
by inserting fixing pins 30 into the mounting holes 28, and further to the
top ends of the support poles 25 of the apparatus by inserting additional
fixing pins 31 into the mounting holes 29.
A pair of slits 72 and 72, extending from the circumferential edge of the
spring 71 toward the inner side of the spring, are formed on both sides of
each of the two fixing points (mounting holes 28 and the fixing pins 30),
which lie on the X line. Another pair of slits 73 and 73, extending from
the circumferential edge of the spring 71 toward the inner side of the
spring, are formed on both sides of each of the two fixing points
(mounting holes 29 | | |
