Abstract:
A system to produce orthogonal beams includes a laser diode operating in conjunction with a collimating lens, an aperture, and a simple compact optic. Three collimated beams are directed toward an optic comprised of components that are bonded together. Beams are reflected from two optical components at right angles to produce plumb beams. Additionally, a beam is reflected from the optic at a right angle, as well as transmitted through the optic, to produce square and level beams. All four beams are orthogonal to each other, have relatively equal power, and are aligned and oriented so as to appear to be originating from a coincident point. Optionally, a fifth orthogonal beam may be produced. An optic in the shape of a cuboid comprised of six small components is also disclosed.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is a continuation of U.S. patent application Ser. No. 10/818,423 filed Apr. 5, 2004, now allowed. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     The present invention generally relates to an optical system that may have utility in construction lay-out and, more specifically, to a system including a simple optic producing at least four orthogonal beams from an incoming collimated laser beam.  
         [0003]     In the construction and home improvement industries, it is quite common for workers to determine level and square along a wall or potential wall site, as well as to find a plumb line from floor to ceiling, during the process of laying out a room. It is advantageous to make these measurements with one device at one time, and at a coincidental point. If the measurements are taken simultaneously with a single device from a coincidental point, the accuracy of the measurements taken increases. By not moving a measurement device from point to point during the process, inaccuracies that might otherwise occur are eliminated. In addition, a person working alone is able to determine level, square and plumb lines simultaneously from a coincidental point. It is particularly advantageous to determine the level, square and plumb lines with beams of light. This eliminates the need for a plumb bob, and does not require that the walls be extensively marked. A single device generating square, level and plumb beams of light allows operation by a single worker.  
         [0004]     Several devices are currently commercially available that assist in making level, square and plumb measurements using visible beams of light. However, these devices are somewhat complicated in construction, and therefore expensive to make. The currently available commercial devices typically have one or more laser diodes and complex multi-part optic assemblies. Because of this complexity, such devices may require careful calibration and correction.  
         [0005]     Therefore, a need exists for a laser optical system that produces level, square and plumb beams of light from a coincidental point. Such a system should be simple in design but also economical, accurate, efficient, easily manufactured and easily assembled.  
       BRIEF SUMMARY OF THE INVENTION  
       [0006]     According to the present invention, an optical system to produce orthogonal beams is disclosed. A light source generates a beam of laser light which is then focused through a collimating lens and aperture arrangement to produce at least three collimated parallel beams of laser light. These three collimated parallel beams of laser light are shone on an optic. The optic, in turn, reflects and transmits the three collimated parallel beams of laser light to produce at least four orthogonal beams of light. The orthogonal beams of light are oriented and positioned so as to appear to have originated at a single coincident point. In addition, the four orthogonal beams of light generally are of equal power.  
         [0007]     The optic is comprised of at least four components bonded together. One of the components is a right angle triangular solid component. The hypotenuse face of the right angle triangular solid component is positioned and coated with a partially reflective material both to reflect and to transmit one of the collimated parallel beams of laser light. Two of the other optic components are right angle trapezoidal solid components. These right angle trapezoidal solid components are each positioned to reflect two of the collimated parallel beams of laser light in opposite directions. The last component is another right angle trapezoidal solid component. The angled face of this right angle trapezoidal solid is positioned adjacent to the hypotenuse face of the right angle triangular solid component coated with the reflective material to form a cuboid. The right angle triangular solid component and right angle trapezoidal solid component have the same refracting index. Therefore, the right angle trapezoidal solid component transmits without refraction the portion of the beam which is transmitted through the right angle triangular component.  
         [0008]     In accordance with another embodiment of the present invention, glass straps are used to bond the optic together without the use of adhesive between adjoining optical components.  
         [0009]     In accordance with yet another embodiment of the present invention, the right angle triangular solid component has a second face coated with a reflective material both to reflect and transmit one of said collimated beams of laser light whereby an additional orthogonal beam of light is produced along the -x axis.  
         [0010]     In accordance with yet another embodiment of the present invention, instead of the reflective material being applied to the hypotenuse face of the right angle triangular solid component, the reflective material is applied to the angled face of the right angle trapezoidal solid component that is positioned adjacent to the hypotenuse face of the right angle triangular solid component.  
         [0011]     In accordance with yet another embodiment of the present invention, at least four right angle trapezoidal solid components comprise the optic. The angled face of one of the right angle trapezoidal solid components is positioned adjacent to the angled face of another right angle trapezoidal solid component to form a cuboid. One of the angled faces of the right angle trapezoidal solid components is coated with a reflective material both to reflect and to transmit the incoming collimated beam of laser light. These two right angle trapezoidal solid components comprising the cuboid have the same refraction index. The two other right angle trapezoidal solid components are positioned to reflect beams of laser light in opposite directions.  
         [0012]     In accordance with still another embodiment of the present invention, at least four right angle triangular solid components are used to construct the optic. The hypotenuse face of one of the right angle triangular solid components is positioned adjacent to the hypotenuse face of another right angle triangular solid component to form a cube. One of the hypotenuse faces of the right angle triangular solid components is coated with a reflective material both to reflect and to transmit the incoming collimated beam of laser light. The two right angle triangular solid components making up the cube have the same refraction index. The other two right angle triangular solid components are positioned to reflect the collimated beams of laser light in opposite directions.  
         [0013]     In accordance with another embodiment of the present invention, at least six right angle triangular solid components are arranged to form a cuboid optic. The cuboid shape increases the ease of both manufacture and assembly.  
         [0014]     Accordingly, it is an object of the present invention to have a device comprising a single laser source and a simple optic that accurately produces four orthogonal beams, originating from a common point. The optic is simple in construction, easily manufactured and does not require complicated calibration or adjustment. Because the design of the optic is simple, the cost of the optic components is minimized.  
         [0015]     Other objects of the present invention will be apparent in light of the description of the invention embodied herein. 
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0016]     The following detailed description of specific embodiments of the present invention can be best understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals, and in which:  
         [0017]      FIG. 1  is a schematic representation of the system comprising a laser diode, a collimating lens, an aperture, and a simple optic for the generation of four orthogonal beams according to an embodiment of the present invention;  
         [0018]      FIG. 2  is a perspective view of the optic of the system comprised of three right angle trapezoidal solid components and one right angle triangular solid component that generates four orthogonal beams from a coincident point according to an embodiment of the present invention;  
         [0019]      FIG. 2A  is an exploded view of the optic of  FIG. 2 ;  
         [0020]      FIG. 3  is a perspective view of the optic of the system bonded with glass straps according to another embodiment of the present invention;  
         [0021]      FIG. 4  is a perspective view of the optic of the system comprised of four right angle trapezoidal solid components according to another embodiment of the present invention;  
         [0022]      FIG. 4A  is an exploded view of the optic of  FIG. 4 ;  
         [0023]      FIG. 5  is a perspective view of the optic of the system comprised of four right angle trapezoidal solid components bonded by the use of glass straps according to another embodiment of the present invention;  
         [0024]      FIG. 6  is a perspective view of the optic of the system comprised of four right angle triangular solid components according to another embodiment of the present invention;  
         [0025]      FIG. 6A  is an exploded view of the optic of  FIG. 6 ;  
         [0026]      FIG. 7  is a perspective view of the optic of the system comprised of six right angle triangular solid components which form a cuboid optic according to another embodiment of the present invention;  
         [0027]      FIG. 7A  is an exploded view of the optic of  FIG. 7 ;  
         [0028]      FIG. 8  is a perspective view of the optic of the system comprised of three right angle trapezoidal solid components and one right angle triangular solid component that generates five orthogonal beams from a coincident point according to another embodiment of the present invention; and  
         [0029]      FIG. 8A  is an exploded view of the optic of  FIG. 8 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0030]      FIG. 1  illustrates a system  10  comprising a single light source  15  generating a beam of light  17  that shines on an optic  40 . The optic  40 , in turn, produces four orthogonal beams  41 ,  42 ,  43 ,  44  which are oriented and aligned so as to appear to be originating from a single coincident point within the optic  40 . The light source  15  is preferably a laser diode which generates a beam of light  17  which is generally elliptical in cross-section. The beam of light  17  is projected generally along the y-axis. The elliptical beam of laser light  17  passes through a collimating lens  20  and in conjunction with an aperture  30  produces three parallel, collimated beams of laser light  32 ,  34 , and  36 . Beam  34 , the “Level” beam, has approximately half the power of the sum of the apertured beams  17 . Beams  32  and  36 , the “Plumb” beams, each have approximately a quarter of the power of the sum of the apertured beams  17 . The three beams  32 ,  34  and  36  are projected onto the optic  40 . The optic  40  both reflects and transmits the three beams  32 ,  34  and  36  to produce four orthogonal beams  41 ,  42 ,  43 ,  44  of about equal power, oriented and aligned to appear to be originating from a single coincident point within the optic  40 .  
         [0031]     The optic  40  is comprised of optical components. Each optical component has a simple geometric shape. The optical components can be comprised of borosilicate crown glass such as, for example, BK7 glass. The optical components may preferably have an optical surface flatness of a quarter wavelength at 635 nm.  
         [0032]     In one embodiment, referring now to  FIGS. 2 and 2 A, four optical components of two simple geometric shapes are used to create the optic  40 . One optical component is a right angle triangular solid  54 , the beam splitter optic. The beam splitter optic  54  is preferably designed to operate between wavelengths of about 620 nm and 650 nm, and is preferably designed for S polarization along the hypotenuse face  55  of the right angle triangular solid  54 . The other faces of the right angle triangular solid  54  preferably have a multi layer dielectric anti-reflective (AR) coating which preferably allows greater than about 97% transmission of the laser light therethrough. The right angle triangular solid  54  is a five-sided solid comprised of two right angle triangular faces and three rectangular faces.  
         [0033]     The three other optical components of the optic  40  are right angle trapezoidal solids  50 ,  52 . The right angle trapezoidal solids  50 ,  52  are six-sided solids comprising two right angle trapezoidal faces and four rectangular faces. The right angle trapezoidal solids  50 ,  52  are preferably designed to operate at a wavelength of between about 620 nm and 650 nm with a preferable wavelength of 635 nm. The angled face  51  of the right angle trapezoidal solid  50 ,  52  is oriented at 45° from the opposite face. Two right angle trapezoidal solids  50 , the 90-degree optics, are positioned to reflect the two quarter power “Plumb” beams  32 ,  36  from their angled faces  51  in opposite directions  41 ,  44  to form a plumb line along the z-axis. Each angled face  51  preferably has a protected enhanced aluminum coating with a reflectivity of preferably greater than about 93% for P polarization with preferably less than about 0.05% transmission of laser light. The third right angle trapezoidal solid  52 , the level optic, is positioned so that its angled face  51  is adjacent to and abuts the hypotenuse face  55  of the beam splitter optic  54 . The two solids together form a cuboid. This cuboid is positioned between the longer of the two parallel faces  53  of the two 90-degree optics  50 . The straight, non-parallel side  57  of the level optic  52  is preferably coated with the multi layer dielectric AR coating. Because both the right angle triangular solid  54  and the right angle trapezoidal solids  50 ,  52  are simple geometric shapes, both manufacturing the optic components and assembling the optic  40  is easier and less expensive.  
         [0034]     In one embodiment, the hypotenuse face  55  of the beam splitter optic  54  is coated with a reflective material. In another embodiment, the angled face  51  of the level optic  52  is coated with the reflective material. In either instance, the reflective material splits an incoming Level beam  34  in half at a 45° angle of incidence. Half of the incoming Level beam  34  will be transmitted through the level optic  52  along the y-axis, forming the level beam  42  with approximately one half of the power of the incoming Level beam  34  or a quarter of the power of the sum of the apertured beams  17 . The other half of the incoming Level beam  34  is reflected from the partially reflective material at a ninety degree angle along the x-axis, forming the square beam  43  with approximately one quarter of the power of the incoming Level beam  34  or a quarter of the power of the original beam of light  17 . Because the level optic  52  has the same index of refraction as the beam splitting optic  54 , there will be no refraction of the transmitted beam  42  at the interface between level optic  52  and beam splitter optic  54 . As a result, the transmitted beam  42  exits the level optic  52  in a direction that is orthogonal to the reflected beam  43 .  
         [0035]     The components  50 ,  52 ,  54  of the optic  40  may be bonded together with an adhesive. The adhesive is applied so as not to interfere with the transmission and reflection of the incoming beams  32 ,  34 ,  36 . In another embodiment, shown in  FIG. 3 , the components  50 ,  52 ,  54  of the optic  40  are bonded together by the use of glass straps  56 . The glass straps  56  are typically attached to components of optic  40 , providing additional structural integrity. The glass straps  56  are bonded to components  50 ,  52  and  54  by adhesive. The adhesive between the glass straps  56  and optical components  50 ,  52 ,  54  replaces the adhesive between the adjoining faces of the components  50 ,  52  and  54 . By eliminating adhesive between adjoining faces, the manufacturable accuracy of the orthogonal beams  41 ,  42 ,  43 ,  44  is improved.  
         [0036]      FIGS. 4 and 4 A illustrate another embodiment of the present invention. In this embodiment, the four components comprising the optic  40  are all of the same geometric shape, the right angle trapezoidal solid shape that was used for three of the components of the previous embodiment. In this embodiment, another level optic  52  replaces the beam splitting optic  54  of  FIG. 2  to form the cuboid. This cuboid is similar to the one described above under  FIG. 2 , albeit this cuboid is slightly longer along the y-axis. As was described above in  FIG. 2 , this cuboid is also positioned between the longer parallel sides of the two ninety-degree optics  50 . One of the angled faces  51  of the two level optic  52  is coated with the partially reflective material to produce the transmitted and reflected beams  42 ,  43 . Again, the four optic components  50 ,  52  of the optic  40  can be bonded together by either adhesive, or by glass straps  56  in conjunction with adhesive, as illustrated in  FIG. 5 .  
         [0037]      FIGS. 6 and 6 A illustrate yet another embodiment of the optic  40 . In this embodiment, instead of using four right angle trapezoidal solids  50 ,  52  to form the optic  40  as described above for  FIG. 4 , four right angle triangular solids  54 ,  60 ,  62  are used. Two right angle triangular solids  60  are coated in the same manner as the ninety-degree optics  50  discussed above for  FIG. 2  in order to reflect beams  32  and  36  at ninety degrees to produce the reflected beams  41  and  44  along the z-axis. In addition, another right angle triangular solid  62  replaces the level optic  52  to form a cube which is positioned between the two right triangular solids  60 . One of the hypotenuse faces of the two right triangular solids  54 ,  62  is coated with partially reflective material to produce the transmitted and reflected beams  42 ,  43  in the same manner as discussed above.  
         [0038]     Another embodiment of the optic  40  of the present invention, illustrated in  FIGS. 7 and 7 A, builds on the optic  40  discussed above in  FIG. 6 . In this embodiment, six right angle triangular solids  54  are used to create a cuboid optic  40 . This is accomplished by adding two additional right angular triangular solids  64  to the optic  40 . The two right angular triangular solids  64  are positioned on the triangular ninety-degree optics  62  to form cubes. Adding the two right angular triangular solids  64  results in three cubes stacked on top of each other to form a cuboid. Due to its simple geometry, a cuboid optic  40  simplifies manufacturing and assembling of the system  10 , thereby reducing the overall cost of the system  10 .  
         [0039]      FIGS. 8 and 8 A illustrate yet another embodiment of optic  40 . In this embodiment, the arrangement of the four optic components  50 ,  52 ,  54  is the same as illustrated in  FIG. 2 . However, in this embodiment, two faces are coated with the reflective material. In one embodiment, the two coated faces are the hypotenuse face  55  of the right angle triangular solid  54  and the face  58  of the right angle triangular solid  54  that the incoming Level beam  34  is not transmitted through. In another embodiment, the two coated faces are the angled face  51  of the level optic  52  and the non-hypotenuse face  58  of the right angle triangular solid  54  that the incoming Level beam  34  is not transmitted through. By coating the additional face  58  of the right angle triangular solid  54  with the reflective material, a fifth orthogonal beam  45  is produce along the -x axis and in the opposite direction of reflected beam  43 . The reflective material coatings on the faces  58  and  55  can be manipulated to achieve varying power ratios of beams  42 ,  43 ,  45  relative to the incident beam  34 .  
         [0040]     It is noted that terms like “preferably,” “commonly,” and “typically” are not utilized herein to limit the scope of the claimed invention or to imply that certain features are critical, essential, or even important to the structure or function of the claimed invention. Rather, these terms are merely intended to highlight alternative or additional features that may or may not be utilized in a particular embodiment of the present invention.  
         [0041]     Having described the invention in detail and by reference to specific embodiments thereof, it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims. More specifically, although some aspects of the present invention are identified herein as preferred or particularly advantageous, it is contemplated that the present invention is not necessarily limited to these preferred aspects of the invention.