Abstract:
An optical assembly includes a first tubular member having a pitched bearing surface proximate one end; a second tubular member having a pitched bearing surface proximate one end; a coupling tubular member fixedly coupled to the second tubular member and rotatably and slideably coupled to the first tubular member; and an optical element received in at least one of the first, the second or the coupling tubular members. At least a portion of the pitched bearing surface of the first tubular member is in engaging contact with at least a portion of the pitched bearing surface of the second tubular member. Rotating the first tubular member with respect to the second tubular member smoothly varies a distance between the first and second tubular members and allows a large, smooth adjustment with little effort. Rotation in a single direction returns the distances to an initial starting point.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
   This application claims benefit under 35 U.S.C. § 119(e) from U.S. Provisional Patent Application No. 60/672,785, filed Apr. 19, 2005. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The method, apparatuses, and articles described herein generally relate to optical devices, and may, for example, be useful in automatic data collection devices such as optical readers of machine-readable symbols. 
   2. Description of the Related Art 
   At present, the most prevalent method of adjusting an optical device appears to employ threaded screws. However, adjusting an optical device through use of a screw has a number of disadvantages. 
   For example, the amount of time and effort required to make an adjustment is disproportionately high relative to the amount of adjustment actually provided. Numerous repeated rotations of the screw are often necessary to achieve the desired adjustment. For example, movement of a lens from one end of the adjustment range to the other end of the adjustment range may take ten rotations of the screw. If, at that point, the user desires to move the lens back to its initial position, the user must rotate the screw ten more times in the opposite direction. In some situations, due to either space constraints or user limitations, it may be difficult to affect both clockwise and counterclockwise rotation with comparative ease. And if the user rotates the screw too far in one direction while the lens is near either end of the adjustment range, the optical device loses the smooth ability to focus. 
   Furthermore, a screw is typically offset from the optical axis. Such an arrangement may cause misalignment or unequal forces in the carriage mechanism, and/or may require adjustment of multiple screws. 
   Optical assemblies and methods of manufacturing the same, which address at least some of the aforementioned problems, would be desirable. 
   BRIEF SUMMARY OF THE INVENTION 
   In one aspect, an optical assembly comprises a first tubular member having a first end, a second end opposite the first end, a longitudinal passage extending between the first and second ends along a longitudinal axis of the first tubular member, and a pitched bearing surface proximate the second end, the pitched bearing surface disposed about the longitudinal axis of the first tubular member such that the pitched bearing surface of the first tubular member is not perpendicular to the longitudinal axis of the first tubular member; a second tubular member having a first end, a second end opposite the first end, a longitudinal passage extending between the first and second ends along a longitudinal axis of the second tubular member, and a pitched bearing surface proximate the second end, the pitched bearing surface disposed about the longitudinal axis of the second tubular member such that the pitched bearing surface of the second tubular member is not perpendicular to the longitudinal axis of the second tubular member; a coupling tubular member having a first end, a second end opposite the first end, a longitudinal passage extending between the first and second ends along a longitudinal axis of the coupling tubular member, the coupling tubular member fixedly coupled to the second tubular member for rotation therewith about the longitudinal axis of the second tubular member, the coupling tubular member rotatably and slideably coupled to the first tubular member, with at least a portion of the pitched bearing surface of the first tubular member in engaging contact with at least a portion of the pitched bearing surface of the second tubular member, such that rotation of the first tubular member with respect to the second tubular member varies a distance between the first end of the first tubular member and the first end of the second tubular member; and at least one optical element received in the longitudinal passage of at least one of the first, the second or the coupling tubular members. 
   In another aspect, an optical assembly comprises a first tubular member having a first end, a second end opposite the first end, a longitudinal passage extending between the first and second ends along a longitudinal axis of the first tubular member, and an endless pitched bearing surface proximate the second end, the pitched bearing surface disposed non-perpendicularly about the longitudinal axis of the first tubular member; a second tubular member having a first end, a second end opposite the first end, a longitudinal passage extending between the first and the second ends along a longitudinal axis of the second tubular member, and an endless pitched bearing surface proximate the second end, the pitched bearing surface disposed non-perpendicularly about the longitudinal axis of the second tubular member; a coupling tubular member having a first end, a second end opposite the first end, a longitudinal passage extending between the first and second ends along a longitudinal axis of the coupling tubular member, the coupling tubular member fixedly coupled to the second tubular member for rotation therewith about the longitudinal axis of the second tubular member, the coupling tubular member rotatably and slideably coupled to the first tubular member, with at least a portion of the pitched bearing surface of the first tubular member in engaging contact with at least a portion of the pitched bearing surface of the second tubular member; and at least one optical element coupled to at least one of the first, the second or the coupling tubular members for movement therewith. 
   In a further aspect, a method of making an optical assembly comprises providing a first tubular member having a first end, a second end opposite the first end, a longitudinal passage extending between the first and the second ends along a longitudinal axis of the first tubular member, and an endless pitched bearing surface proximate the second end, the pitched bearing surface disposed about the longitudinal axis of the first tubular member such that the pitched bearing surface of the first tubular member is not perpendicular to the longitudinal axis of the first tubular member; providing a second tubular member having a first end, a second end opposite the first end, a longitudinal passage extending between the first and the second ends along a longitudinal axis of the second tubular member, and an endless pitched bearing surface proximate the second end, the pitched bearing surface disposed about the longitudinal axis of the second tubular member such that the pitched bearing surface of the second tubular member is not perpendicular to the longitudinal axis of the second tubular member; providing a coupling tubular member having a first end, a second end opposite the first end, a longitudinal passage extending between the first and the second ends along a longitudinal axis of the coupling tubular member; fixedly coupling the coupling tubular member to the second tubular member for rotation therewith about the longitudinal axis of the second tubular member; rotatably and slideably coupling the coupling tubular member to the first tubular member with at least a portion of the pitched bearing surface of the first tubular member in engaging contact with at least a portion of the pitched bearing surface of the second tubular member; providing at least one optical element; and coupling the at least one optical element to at least one of the first, the second or the coupling tubular members for movement therewith. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     In the drawings, identical reference numbers identify similar elements or acts. The sizes and relative positions of elements in the drawings are not necessarily drawn to scale. For example, the shapes of various elements and angles are not drawn to scale, and some of these elements are arbitrarily enlarged and positioned to improve drawing legibility. Further, the particular shapes of the elements as drawn, are not intended to convey any information regarding the actual shape of the particular elements, and have been solely selected for ease of recognition in the drawings. 
       FIG. 1  is an isometric view of an exemplary optical assembly having an internal coupling member according to one illustrated embodiment. 
       FIG. 2  is an exploded view of the optical assembly of  FIG. 1 . 
       FIG. 3  is an isometric view of an exemplary optical assembly having an external coupling member according to another illustrated embodiment. 
       FIG. 4  is a side elevational view of an exemplary optical assembly in a non-extended state according to one illustrated embodiment. 
       FIG. 5  is a side elevational view of an exemplary optical assembly in an intermediate state between a non-extended state and a fully extended state according to one illustrated embodiment. 
       FIG. 6  is a side elevational view of an exemplary optical assembly in a fully extended state according to one illustrated embodiment. 
       FIG. 7  is a flow diagram showing a method of making an optical assembly, according to one illustrated embodiment. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   In the following description, certain specific details are set forth in order to provide a thorough understanding of various disclosed embodiments. However, one skilled in the relevant art will recognize that embodiments may be practiced without one or more of these specific details, or with other methods, components, materials, etc. In other instances, well-known structures associated with optical devices and optical elements have not been shown or described in detail to avoid unnecessarily obscuring descriptions of the embodiments. 
   Unless the context requires otherwise, throughout the specification and claims which follow, the word “comprise” and variations thereof, such as, “comprises” and “comprising” are to be construed in an open, inclusive sense, that is as “including, but not limited to.” 
   Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. 
   The headings provided herein are for convenience only and do not interpret the scope or meaning of the embodiments. 
     FIGS. 1 and 2  show an optical assembly  10   a  according to one embodiment. The optical assembly  10   a  is comprised of a first tubular member  12 , a second tubular member  14 , a coupling tubular member  16   a,  and an optical element  18 . 
   The first tubular member  12  comprises a first end  20 , a second end  22 , and a longitudinal passage  21  extending between the first end  20  and second end  22  along a longitudinal axis  23  of the first tubular member  12 . The first tubular member  12  may be formed of one or more of a variety of materials, including but not limited to metals, plastics, and/or composites. In at least one embodiment, the first tubular member  12  has a circular cross-section taken substantially perpendicularly to the longitudinal axis  23  of the first tubular member  12 . The first tubular member  12  has a pitched bearing surface  24  proximate the second end  22 , and disposed about the longitudinal axis  23  of the first tubular member  12  such that the pitched bearing surface  24  of the first tubular member  12  is not perpendicular to the longitudinal axis  23  of the first tubular member  12 . In at least one embodiment, the pitched bearing surface  24  is a closed or endless surface. A closed, or endless, pitched bearing surface is defined to include a pitched surface with no terminus. The angle formed between the pitched bearing surface  24  and the cross-section of the first tubular member  12  may be twenty degrees or any other suitable angle. 
   Similarly, the second tubular member  14  comprises a first end  26 , a second end  28 , and a longitudinal passage  27  extending between the first end  26  and second end  28  along a longitudinal axis  29  of the second tubular member  14 . The second tubular member  14  may be formed of one or more of a variety of materials, including but not limited to metals, plastics, and/or composites. In at least one embodiment, the second tubular member  14  has a circular cross-section taken substantially perpendicularly to the longitudinal axis  29  of the second tubular member  14 . In at least one embodiment, the longitudinal axes  23 ,  29  of the first tubular member  12  and second tubular member  14 , respectively, are coaxial. The second tubular member  14  has a pitched bearing surface  30  proximate the second end  28 , and disposed about the longitudinal axis  29  of the second tubular member  14  such that the pitched bearing surface  30  of the second tubular member  14  is not perpendicular to the longitudinal axis  29  of the second tubular member  14 . In at least one embodiment, the pitched bearing surface  30  is a closed surface. 
   The coupling tubular member  16   a  also has a first end  32 , a second end  34 , and a longitudinal passage  33  extending between the first end  32  and second end  34  along a longitudinal axis  35  of the coupling tubular member  16   a.  The coupling tubular member  16   a  may be formed of one or more of a variety of materials, including but not limited to metals, plastics, and/or composites. In at least one embodiment, the coupling tubular member  16   a  has a circular cross-section taken substantially perpendicularly to the longitudinal passage  33  of the coupling tubular member  16   a.    
   The coupling tubular member  16   a  is fixedly coupled to the second tubular member  14  for rotation therewith about the longitudinal axis  29  of the second tubular member  14 . In at least one embodiment, the coupling tubular member  16   a  is press fit to the second tubular member  14 . The coupling tubular member  16   a  is rotatably and slideably coupled to the first tubular member  12 . 
   In the specific embodiment of  FIGS. 1 and 2 , the first end  32  of coupling tubular member  16   a  is secured within the longitudinal passage  21  of the first tubular member  12 , for example by press fitting. The second end  34  of the coupling tubular member  16   a  is rotatably and slideably received within the longitudinal passage  27  of the second tubular member  14 . Portions of the coupling tubular member  16   a  are shown in broken line to indicate the location of the first end  32  of the coupling tubular member  16   a  within the first tubular member  12  and the second end  34  of the coupling tubular member  16   a  within the second tubular member  14 . 
   In operation, at least a portion of the pitched bearing surface  30  of the second tubular member  14  is in engaging contact with at least a portion of the pitched bearing surface  24  of the first tubular member  12 . Rotation of the first tubular member  12  with respect to the second tubular member  14  smoothly varies a distance between the first end  20  of the first tubular member  12  and a first end  26  of the second tubular member  14 . In at least one embodiment, the closed nature of at least one of the pitched bearing surfaces  24  and  30  allows the optical assembly to achieve both full extension and full retraction without reversing rotational direction. 
   While the optical element  18  is illustrated as received within the first tubular member  12 , the optical element  18  or additional optical elements may be received in the second tubular member  14  or the coupling tubular member  16 . In at least one embodiment, the optical element  18  may, for example, comprise one or more lenses mounted in the longitudinal passage  21 ,  27 ,  33  of the first, the second and/or the coupling tubular members  12 ,  14 ,  16 , respectively. In at least one embodiment, at least one optical element  18  is proximate the first end  20  of the first tubular member  12 . 
     FIG. 3  shows an alternative optical assembly  10   b.  This alternative embodiment, and those alternative embodiments and other alternatives described herein, are substantially similar to previously described embodiments, and common acts and structures are identified by the same reference numbers. Only significant differences in operation and structure are described below. 
     FIG. 3  shows an embodiment in which the structure of the first tubular member  12 , second tubular member  14 , and optical element  18  are similar to the elements described in  FIG. 1 . However, the embodiment employs a larger coupling tubular member  16   b.  Additionally, in the specific embodiment of  FIG. 3 , the second end  22  of the first tubular member  12  and the second end  28  of the second tubular member  14  are both received within the longitudinal passage  33  of the coupling tubular member  16   b.  Portions of the first tubular member  12  and second tubular member  14  are shown in broken line in  FIG. 3  to indicate the location of the those portions within the coupling tubular member  16   b  for the specific embodiment of  FIG. 3 . 
   The coupling tubular member  16   b  is fixedly coupled to the second tubular member  14  for rotation therewith about the longitudinal axis  29  of the second tubular member  14 . In at least one embodiment, the second tubular member  14  is press fit into the longitudinal passage  33  of the coupling tubular member  16   b.  The first tubular member  12  is rotatably and slideably received in the coupling tubular member  16   b.  In operation, at least a portion of the pitched bearing surface  30  of the second tubular member  14  is in engaging contact with at least a portion of the pitched bearing surface  24  of the first tubular member  12 . Rotation of the first tubular member  12  with respect to the second tubular member  14  smoothly varies a distance between the first end  20  of the first tubular member  12  and a first end  26  of the second tubular member  14 . In at least one embodiment, the closed nature of at least one of the pitched bearing surfaces  24  and  30  allows the optical assembly to achieve both full extension and full retraction without reversing rotational direction. 
   The optical element  18  is received either within the first tubular member  12  or the second tubular member  14 . In at least one embodiment, the optical element  18  may, for example, comprise one or more lenses mounted in the longitudinal passage of the first tubular member  12 . In at least one embodiment, at least one lens is proximate the first end  20  of the first tubular member  12 . 
     FIG. 4  shows the optical assembly  10   a  in a non-extended state according to one embodiment. The structure of first tubular member  12 , second tubular member  14 , coupling tubular member (not specifically illustrated in  FIG. 4 ), and optical element  18  (not specifically illustrated in  FIG. 4 ) are as described in  FIGS. 1 and 2 . In the non-extended state, the distance between the first end  20  of first tubular member  12  and the first end  26  of second tubular member  14  is at a minimum. Additionally, pitched bearing surface  24  of first tubular member  12  and pitched bearing surface  30  of second tubular member  14  are in substantially complete contact over their entire surfaces. 
     FIG. 5  shows the optical assembly  10   a  in an intermediate state between a non-extended state and a fully extended state according to one embodiment. The structure of first tubular member  12 , second tubular member  14 , coupling tubular member (not specifically illustrated in  FIG. 5 ), and optical element  18  (not specifically illustrated in  FIG. 5 ) are as described in  FIGS. 1 and 2 . In the intermediate state of adjustability, the distance between the first end  20  of first tubular member  12  and the first end  26  of second tubular member  14  is neither at a minimum nor a maximum. Additionally, pitched bearing surface  24  of first tubular member  12  and pitched bearing surface  30  of second tubular member  14  are in partial contact. 
     FIG. 6  shows the optical assembly  10   a  in a fully extended state, according to one embodiment. The structure of first tubular member  12 , second tubular member  14 , coupling tubular member  16  (not specifically illustrated in  FIG. 6 ), and optical element  18  (not specifically illustrated in  FIG. 6 ) are as described in  FIGS. 1 and 2 . In the fully extended state, the distance between the first end  20  of first tubular member  12  and the first end  26  of second tubular member  14  is at a maximum. Additionally, pitched bearing surface  24  of first tubular member  12  is in minimal contact with the pitched bearing surface  30  of second tubular member  14 . 
     FIG. 7  is a flow diagram showing a high-level method  700  of making an exemplary optical assembly  10   a,    10   b  according to one illustrated embodiment, starting at  702 . 
   At  702 , a first tubular member  12  is provided. The first tubular member  12  may be similar to the first tubular member  12  illustrated in the attached drawings, or it can take other forms consistent with the spirit and scope of the invention. 
   At  704 , a second tubular member  14  is provided. The second tubular member  14  can be similar to the second tubular member  14  illustrated in the attached drawings, or it can take other forms consistent with the spirit and scope of the invention. 
   At  706 , a coupling tubular member  16  is provided. The coupling tubular member  16  can be provided in one of many different forms. By way of example and not limitation, it can be similar to the coupling tubular member  16   a  of  FIGS. 1 and 2 , or it can be more similar to the coupling tubular member  16   b  of  FIG. 3 . 
   At  708 , the coupling tubular member  16  is fixedly coupled to the second tubular member  14 . One method of coupling the two components is by press fitting one to the other, although other methods of coupling may be used and are within the spirit and scope of the invention. The second tubular member  14  may receive the coupling tubular member  16  as shown in  FIGS. 1 and 2 , or the coupling tubular member  16  may receive the second tubular member as shown in  FIG. 3 . 
   At  710 , the coupling tubular member  16  is rotatably and slideably coupled to the first tubular member  12 . In a non-extended state of optic assembly  10 , the first end  20  of the first tubular member  12  is at a minimum distance from the first end  26  of the second tubular member  14 . In a fully extended state of optic assembly  10 , the first end  20  of the first tubular member  12  is at a maximum distance from the first end  26  of the second tubular member  14 . 
   At  712 , at least one optical element  18  is provided. The optical element  18  may take the form of one or more lenses, prisms, reflectors, refractors, apertures and/or filters, or any other optical element. 
   At  714 , the one or more optical elements are coupled to the first tubular member  12 , the second tubular member  14 , and/or the coupling tubular member  16 . If more than one optical element is provided, they may be coupled to different tubular members or to the same tubular member  12 ,  14 ,  16 . 
   The above description of illustrated embodiments, including what is described in the Abstract, is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Although specific embodiments of and examples are described herein for illustrative purposes, various equivalent modifications can be made without departing from the spirit and scope of the invention, as will be recognized by those skilled in the relevant art. The teachings provided herein of the invention can be applied to other optical assemblies, not necessarily the exemplary optical assembly generally described above. For example, the teaching may apply to an optical assembly having additional tubular members and tubular coupling members. The teaching may apply to tubular members having non-circular cross-sections, including but not limited to elliptical, square, rectangular, or hexagonal cross-sections. Further, the acts of method  700  may occur in a different order, and the method  700  may omit some acts and/or include additional acts. 
   The various embodiments described above can be combined to provide further embodiments. All of the U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications and non-patent publications referred to in this specification and/or listed in the Application Data Sheet, including but not limited to U.S. provisional patent application Ser. No. 60/672,785, are incorporated herein by reference, in their entirety. Aspects of the invention can be modified, if necessary, to employ systems, circuits and concepts of the various patents, applications and publications to provide yet further embodiments of the invention. 
   These and other changes can be made to the invention in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the invention to the specific embodiments disclosed in the specification and the claims, but should be construed to include all assemblies, and methods of manufacturing the same, that accord with the claims. Accordingly, the invention is not limited by the disclosure, but instead its scope is to be determined entirely by the following claims.