Title: Hollow retroreflector assembly with a single bonding surface and single mounting surface mounting member
Abstract: A retroreflector assembly is assembled by adhering a retroreflector to a mounting member along a single flat back surface of the retroreflector and a flat surface of the mounting member. The retroreflector does not otherwise contact the mounting member. The retroreflector includes three plates having optically flat reflective front surfaces disposed at right angles to each other, wherein each of the plates further has a back surface disposed on an opposite side of the plate from the optically flat reflective front surface. The mounting member comprises a bonding portion and a base portion connected to the bonding portion, wherein the bonding portion is adhered to the back surface of one of the three plates, and wherein the bonding portion comprises a same material as the one of the three plates to which the bonding portion is adhered.
Patent Number: 6,902,279 Issued on 06/07/2005 to Lyons, III
| Inventors:
|
Lyons, III; James Joseph (Keedysville, MD)
|
| Assignee:
|
PROSystems, Inc. (Kearneysville, WV)
|
| Appl. No.:
|
238591 |
| Filed:
|
September 11, 2002 |
| Current U.S. Class: |
359/529; 359/530 |
| Intern'l Class: |
G02B 005/12.2 |
| Field of Search: |
359/529,850,846,848,530
|
References Cited [Referenced By]
U.S. Patent Documents
Other References
Bass et al, Handbook of Optics, 1995, McGraw-Hill, Inc., vol. I Fundamentals,
Techniques, and Design, pp. 37.22-37.23.
|
Primary Examiner: Cherry; Euncha P.
Attorney, Agent or Firm: Volentine, Francos & Whitt, PLLC
Parent Case Text
CROSS-REFERENCES TO RELATED APPLICATIONS
The present application claims the priority benefit from U.S. provisional patent
application No. 60/318,365, filed on Sep. 12, 2001 naming inventor James Lyons
III, the entire contents of which are hereby incorporated herein by reference for
all purposes as if fully set forth herein.
Claims
1. A retroreflector assembly, comprising:
a retroreflector including three plates having optically flat reflective front
surfaces disposed at right angles to each other, wherein each of said plates further
has a back surface disposed on an opposite side of the plate from the optically
flat reflective front surface; and
a mounting member adapted for mounting said retroreflector thereon, comprising
a bonding portion and a base portion connected to the bonding portion, wherein
said bonding portion is adhered to said back surface of one of said three plates,
and wherein said bonding portion comprises a same material as the one of said three
plates to which said bonding portion is adhered.
2. The retroreflector assembly of claim 1, wherein the bonding portion and the
one of said three plates to which said bonding portion is adhered are each comprised
of glass.
3. The retroreflector assembly of claim 2, wherein said base portion comprises
a different material from said bonding portion.
4. The retroreflector assembly of claim 3, wherein said base portion comprises
a metal.
5. The retroreflector assembly of claim 4, wherein said metal is aluminum.
6. The retroreflector assembly of claim 1, wherein said base portion comprises
a different material from said bonding portion.
7. The retroreflector assembly of claim 6, wherein said base portion comprises
a metal.
8. The retroreflector assembly of claim 7, wherein said metal is aluminum.
9. The retroreflector assembly of claim 1, wherein said mounting member further
comprises means for attaching said retroreflector assembly to a support.
10. The retroreflector assembly of claim 9, wherein said base member has a bore
extending therein.
11. The retroreflector assembly of claim 10, wherein said bore is threaded for
receipt of a substantially correspondingly threaded member extending from the support.
12. The retroreflector assembly of claim 1, further comprising an adhesive adhering
said bonding portion to said back surface of the one of said three plates.
13. The retroreflector assembly of claim 12 wherein said adhesive is a semi-rigid epoxy.
14. The retroreflector assembly of claim 1, wherein said mounting member further
comprises an adhesive adhering said base portion to said bonding portion.
15. For a retroreflector having three plates having optically flat reflective
front surfaces disposed at right angles to each other and each plate having a back
surface disposed on an opposite side of the plate from the optically flat reflective
front surface, a mounting member adapted for mounting said retroreflector thereon
along the back surface of one of the plates, the mounting member comprising:
a base portion; and
a bonding portion connected to the base portion, wherein said bonding portion
comprises a same material as the one of the three plates to which it is adhered.
16. The mounting member of claim 15, wherein said bonding portion is comprised
of glass.
17. The mounting member of claim 16, wherein said base portion comprises a different
material from said bonding portion.
18. The mounting member of claim 17, wherein said base portion comprises a metal.
19. The mounting member of claim 18, wherein said metal is aluminum.
20. The mounting member of claim 15, wherein said base portion comprises a different
material from said bonding portion.
21. The mounting member of claim 20, wherein said base portion comprises a metal.
22. The mounting member of claim 21, wherein said metal is aluminum.
23. The mounting member of claim 15, wherein said mounting member further comprises
means for attaching the mounting member to a support.
24. The mounting member of claim 23, wherein said base member has a bore extending therein.
25. The mounting member of claim 24, wherein said bore is threaded for receipt
of a substantially correspondingly threaded member extending from the support.
26. A retroreflector assembly, comprising:
a retroreflector including three plates having optically flat reflective front
surfaces disposed at right angles to each other and all three plates touching each
other at a central junction, each plate having a back surface disposed on an opposite
side of the plate from the optically flat reflective front surface, wherein one
of the three plates further includes an extension portion extending from the back
surface of said one plate away from and beneath the central junction by a predetermined
distance; and
a mounting member adapted for mounting said retroreflector thereon, comprising
a base portion adhered to said extension portion of said one plate.
27. The retroreflector assembly of claim 26, wherein said base portion comprises
a different material from said extension portion.
28. The retroreflector assembly of claim 27, wherein said base portion comprises
a metal.
29. The retroreflector assembly of claim 28, wherein said metal is aluminum.
30. The retroreflector assembly of claim 26, wherein said mounting member further
comprises means for attaching the mounting member to a support.
31. The retroreflector assembly of claim 30, wherein said base member has a bore
extending therein.
32. The retroreflector assembly of claim 31, wherein said bore is threaded for
receipt of a substantially correspondingly threaded member extending from the support.
33. The retroreflector assembly of claim 1, wherein said bonding portion is adhered
to said back surface of said one of said three plates along outer edges of said
back surface.
34. The retroreflector assembly of claim 1, wherein said adhesive is disposed
along outer edges of said back surface of said one of said three plates in a generally
V-shaped pattern.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed to mounted retroreflectors, more particularly
to a retroreflector assembly having a single bonding surface for adhering a retroreflector
to a mounting member, and to a single bonding surface mounting member for mounting
a retroreflector.
2. Description of the Related Art
Hollow retroreflectors, consisting of three plates having optically flat reflective
surfaces disposed at right angles to each other, and meeting at what can be described
as a common inside corner of an imaginary cube (hereinafter referred to as "the
central junction"), are well known in the art. In general, hollow retroreflectors
return reflected light along a path parallel to incident light. In insuring this
performance, the relative perpendicularity of the reflective surfaces needs to
be maintained.
When the hollow retroreflector is to be mounted in position for a particular
application, it is important to secure the retroreflector without applying stresses,
which could deflect the reflective surfaces out of their perpendicular alignment.
The mounting member for the retroreflector should also minimize the effect of external
stresses that the retroreflector may be subject to in operation.
Previous retroreflector assemblies typically include providing the attachment
of the retroreflector to the mounting member on at least two surfaces of the retroreflector.
Such mounting can result in stresses being induced on the retroreflector.
U.S. Pat. No. 5,335,111 describes a prior art hollow retroreflector assembly.
In the prior art hollow retroreflector mounting member, the mounting member has
first and second receiving surfaces disposed at right angles to each other. The
first receiving surface is adhered to a portion of the first side of one of the
plates of the retroreflector, and the second receiving surface is adhered to a
portion of the second side of the same plate of the retroreflector.
Accordingly, with the prior art mounting member and retroreflector assembly,
the retroreflector must be bonded to the mounting member in two places at two different
bonding surfaces. The mounting member is also bonded to the sides of the retroreflector plate.
Thus, the bonding process is somewhat complicated. Also, because there are
two different bonding surface steps, there is an increased potential for damage
during the bonding process. Also, because there are two different bonding surfaces,
there is an increased possibility of stresses being applied during the bonding
process, perhaps deflecting the plate from true perpendicularity.
Accordingly, it would be advantageous to provide an improved mounting
member for a retroreflector. It would also be advantageous to provide an improved
retroreflector assembly. Other and further objects and advantages will appear hereinafter.
SUMMARY OF THE INVENTION
The present invention is therefore directed to an improved mounting member for
a retroreflector, a hollow retroreflector assembly, and associated methods of mounting
a retroreflector to a mounting member.
These and other objects of the present invention will become more readily apparent
from the detailed description given hereinafter. However, it should be understood
that the detailed description and specific examples, while indicating the preferred
embodiments of the invention, are given by way of illustration only, since various
changes and modifications within the spirit and scope of the invention will become
apparent to those skilled in the art from this detailed description.
In one aspect of the invention, a retroreflector assembly comprises a retroreflector
including three plates having optically flat reflective front surfaces disposed
at right angles to each other, wherein each of the plates further has a back surface
disposed on an opposite side of the plate from the optically flat reflective front
surface, and a mounting member adapted for mounting the retroreflector thereon,
comprising a bonding portion and a base portion connected to the bonding portion,
wherein the bonding portion is adhered to the back surface of one of the three
plates, and wherein the bonding portion comprises a same material as the one of
the three plates to which the bonding portion is adhered.
In another aspect of the invention, a mounting member is adapted for mounting
thereon a retroreflector having three plates having optically flat reflective front
surfaces disposed at right angles to each other and each plate having a back surface
disposed on an opposite side of the plate from the optically flat reflective front
surface, the mounting member being adhered to the retroreflector along the back
side of one of the plates. The mounting member comprises a base portion and a bonding
portion connected to the base portion, wherein the bonding portion comprises a
same material as the one of the three plates to which it is adhered.
In still another aspect of the invention, a retroreflector assembly comprises
a retroreflector including three plates having optically flat reflective front
surfaces disposed at right angles to each other and all three plates touching each
other at a central junction, each plate having a back surface disposed on an opposite
side of the plate from the optically flat reflective front surface, wherein one
of the three plates further includes an extension portion extending from the back
surface of said one plate away from and beneath the central junction by a predetermined
distance, and a mounting member adapted for mounting said retroreflector thereon,
comprising a base portion adhered to said extension portion of said one plate.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective side view of a retroreflector assembly in accordance
with an embodiment of the present invention;
FIG. 2 is a perspective three-quarters top view of the retroreflector assembly
of FIG. 1;
FIG. 3 is a perspective bottom view of the mount of FIG. 1;
FIG. 4 is a detailed perspective side view of a notch in the mount of FIG. 1;
FIG. 5 is a perspective three-quarters top view of the mount of FIG. 1;
FIG. 6A is a perspective top view of a mount for a retroreflector according
to another embodiment of the present invention;
FIG. 6B is a perspective top view of a retroreflector according to another embodiment
of the present invention, to be mounted on the mount shown in FIG. 6A;
FIG. 7 is a perspective top view of a retroreflector according to another embodiment
of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following description, for purposes of explanation and not limitation,
specific details are set forth in order to provide a thorough understanding of
the present invention. However, it will be apparent to one skilled in the art that
the present invention may be practiced in other embodiments that depart from these
specific details. In other instances, detailed descriptions of well-known devices
and methods are omitted so as not to obscure the description of the present invention
with unnecessary details.
FIGS. 1-2 illustrate perspective side and top views, respectively, of a hollow
retroreflector
20 on a mounting member
10. The retroreflector
20
has three plates
27-
29 having opposing reflective front surfaces,
21-
23, and corresponding back surfaces
24-
26. The mounting
member
10 includes a base portion
12 and a bonding portion
14.
As can be seen in FIGS. 1-2, the retroreflector
20 is adhered to the bonding
portion
14 along one of the back surfaces
24-
26 of the retroreflector,
here shown as back surface
26. Beneficially, the bonding portion
14
is adhered to the back surface
26 using an epoxy, beneficially a semi-rigid
epoxy. The epoxy is beneficially applied along side the outer edges of the back
surface
26 in a generally "V-shaped" pattern.
In the particular configuration shown in FIGS. 1 and 2, and shown in more detail
in the various views of the mounting member alone in FIGS. 3-5, the bonding portion
14 and the base portion
12 may be made of different materials. For
example, the base portion
12, which is to be affixed to a support member
at a desired position, may be made of an easily machined metal, e.g., aluminum.
This is of particular interest if an attachment hole or bore
16 (which may
be threaded) is to be provided in the base portion
12, as can be seen in
FIG.
3.
Significantly, the bonding portion
14 may be of the same material
as the one of the three plates of the retroreflector
20 to which the bonding
portion
14 is adhered. In a preferred embodiment, the bonding portion
14
and the one of the three plates of the retroreflector
20 to which the bonding
portion
14 is adhered are each made of glass. As such, the bonding portion
14 functions as a transition piece having the same thermal and mechanical
characteristics as the retroreflector
20 to be bonded thereto. This two-piece
design allows the base portion
12 and the bonding portion
14 to be
tailored for use with a particular instrument or support and/or with a particular retroreflector.
As can be seen in detail in the embodiment shown in FIG. 4, the bonding portion
14 is attached to the base portion
12 on two surfaces which are formed
at 90 degrees with respect to each other in a notch
18 which is formed in
the base portion
12. The stepped structure of the base portion
12
allows the notch
18 to be provided therein while offering substantial contact
to the bonding portion
14 to insure rigid attachment thereof. Beneficially,
the bonding portion
14 is attached to the base portion
12 by an epoxy.
This particular bonding arrangement provides a strong rigid thermally stable mount.
In this design, stresses induced by temperature are mitigated at the juncture of
the base portion
12 and the bonding portion
14. However, it should
be understood that other arrangements for connecting the bonding portion
14
to the base portion
12 are contemplated.
FIG. 6A illustrates a unitary design of a mounting member
50 for receiving
a retroreflector
60, shown in FIG. 6B therein. As before, the retroreflector
60 includes three plates
67-
69 having three reflective front
surfaces
61-
63 and three corresponding back surfaces
64-
66.
Here, the mounting member
50 is an integral piece, i.e., the base portion
52 and the bonding portion
54 are of the same material. This same
material may provide the desired thermal stability by being made of the same materials
the bonding portion
14 was made of in the first embodiment, i.e., the same
material as that of the retroreflector
60 to be bonded thereto (e.g., glass).
Again, only one back surface
64-
66 is bonded to the bonding portion
54. Further, an attachment hole or bore
56 (which may be threaded)
may be provided in the mounting member
50.
In both configurations, a single flat back surface of the retroreflector is bonded
to a flat surface of the mounting member. The retroreflector does not otherwise
contact the mounting member. The use of only a single surface on the back reflector
reduces stresses imposed on the retroreflector. Further, the use of flat planar
surfaces allows a rigid bonding of the retroreflector to be realized while only
bonding to a single surface. The bonding of the flat surfaces is easier to realize
and results in a simple mount, both of which reduce costs associated with the mounted
retroreflector. Finally, thermal stability may be achieved by matching the thermal
characteristics of the mount in contact with the retroreflector to that of the retroreflector.
FIG. 7 illustrates an alternative arrangement wherein a retroreflector
70
comprising three plates
77-
79 having three reflective front surfaces
71-
73 and three corresponding back surfaces
74-
76.
Here, one of the three plates
77-
79 (e.g.,
78) includes an
extension portion
100 extending therefrom. The extension portion
100
extends from the back surface of the plate away
78 away from and beneath
the central junction where the three plates
77-
79 all meet. The extension
portion
100 performs corresponding functions to the bonding portion
14
shown in the first embodiment, but has the advantage of not requiring to be bonded
to the retroreflector
70 as it is instead integrally formed with one of
the plates
78. The extension portion
100 may be formed of any desired
shape or length, but provides thermal relief from a location where it is bonded
to a base member (e.g., the base member
12) and the location of the reflective
surfaces of the retroreflector
70.
While preferred embodiments are disclosed herein, many variations are possible
which remain within the concept and scope of the invention. Such variations would
become clear to one of the ordinary skill in the art after inspection of the specification,
drawings and claims herein. The invention therefore is not to be restricted except
within the spirit and scope of the appended claims.
*
