Patent Publication Number: US-2011063853-A1

Title: Laser liner

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a laser liner. 
     2. Description of the Prior Art 
     Refer to  FIG. 1  for a multidirectional laser pointer of a Taiwanese patent numbered 570188. A light module  1  emits light  6  passing through a condensing lens  2  and a bar-shaped lens  3 , the emitted light  6  is thereafter refracted to form refracted light  4 A with a maximum aperture of 120-150 degrees. 
     Refer to  FIG. 2 . To increase the maximum aperture of the emitted light, a conical pole  5  is provided in substitution for the bar-shaped lens. The light  6  is reflected by the conical pole  5  to form reflected light  4 B with a maximum aperture of 180 degrees. 
     However, such conical pole  5  is hard to assembled and easily damaged during the assembling procedure, and it has to be positioned by a supporter  7 , which screens part of the scattered light  4 B. 
     SUMMARY OF THE INVENTION 
     The main object of the present invention is to provide a laser liner that is easily-assemblable and is suitable to emit reflected light with a maximum aperture of 180 degrees. 
     To achieve the above object, a laser liner is provided. The laser liner includes a light module, a condensing lens and a cylindrical diverging lens. The light module produces a point source of light, which penetrating through the condensing lens to form a surface source of light. The diverging lens is disposed next to the condensing lens and has a plane surface facing the condensing lens. The diverging lens further has a surface opposite to the plane surface, and the surface opposite to the plane surface has a concave right circular conical surface. A ratio of a length of a generatrix of the conical surface to a diameter of a directrix of the conical surface is √{square root over (2)}2, wherein as the light emitted from the surface source enters the diverging lens from the plane surface, the light entering the diverging lens is reflected by the conical surface to form a reflected light, and an included angle between the reflected light and an axis of the conical surface is 90 degrees. 
     The present invention will become more obvious from the following description when taken in connection with the accompanying drawings, which show, for purpose of illustrations only, the preferred embodiments in accordance with the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a profile showing a first prior art; 
         FIG. 2  is a profile showing a second prior art; 
         FIG. 3A  is a profile showing a laser liner in accordance with a preferred embodiment of the present invention; 
         FIG. 3B  is a profile showing a laser liner at another view angle in accordance with a preferred embodiment of the present invention; 
         FIG. 4  is an explosive drawing showing a laser liner in accordance with a preferred embodiment of the present invention; 
         FIG. 5  is a profile showing a path of laser in a laser liner in accordance with a preferred embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Refer to  FIG. 3A ,  FIG. 3B  and  FIG. 4-5 . A laser liner of the present invention includes a light module  10 , a condensing lens  20  and a cylindrical diverging lens  30 . The light module  10  is used to produce a point source of light. The condensing lens  20  is disposed next to the light module  10 . Light  101  emitted from the point source penetrates through the condensing lens  20  to condense into a surface source of light. The diverging lens  30  is disposed next to the condensing lens  20  and away from the light module  10 , i.e. the condensing lens  20  is disposed between the light module  10  and the diverging lens  30 . The diverging lens  30  has a plane surface facing the condensing lens  20 , and the diverging lens  30  further has a surface opposite to the plane surface. The surface opposite to the plane surface has a concave right circular conical surface  31  formed thereon. A ratio of a length of a generatrix of the conical surface  31  to a diameter of a directrix of the conical surface  31  is √{square root over (2)}2. Specifically, in a vertical profile passing through an apex of the conical surface  31 , the section of the conical surface  31  is an isosceles right triangle. The length of the generatrix is exactly the length of each equal side of the isosceles right triangle, and the diameter of the directrix is exactly the length of the hypotenuse of the isosceles right triangle. As light  201  emitted from the surface source enters the diverging lens  30  from the plane surface, the light entering the diverging lens  30  is reflected by the conical surface  30  to form a reflected light  301 . Thus, an included angle between the reflected light  301  and an axis of the conical surface is 90 degrees, i.e. the maximum aperture of the reflected light  301 , which is the angle between two opposite reflected light  301 , is 180 degrees. 
     The laser liner further includes a shell  30 , which is a hollow cylinder. The light module  10  and the diverging lens  30  are disposed on two opposite end of the shell  40  while sandwiching the condensing lens  20 . 
     There are two first positioners  41  and two adjusting elements  42  disposed on the shell  40 . The first positioners  41  clamp the light module  10  from two opposite side of the shell  40 . A distal end of each adjusting element  42  has a conical surface to abut against a bottom surface of the light module  10 . The adjusting element  42  is then adjustable to move toward or away from the interior of the shell  40 , further adjusting the position of the light module  10  such that the light module  10  and the shell  40  are coaxial. 
     The light module  10  can be a laser module or a LED module, and the light module  10  includes a light source generator  11 , a print circuit board  12  and an electric contact  13 . The light source generator  11  is disposed on the print circuit board  12  and electrically connects to the electric contact  13 . The first positioners  41  thus clamp the light source generator  11 , and the conical surfaces of the adjusting elements  42  abut against a bottom surface of the light source generator  11 . 
     There are at least three second positioners  43  (four second positioners are shown in the drawings) disposed on the shell  40  and clamping the diverging lens  30 . The second positioners  43  are used to adjust the level position of the diverging lens  30  such that the diverging lens  30 , the condensing lens  20  and the light module  10  are coaxial. 
     The condensing lens  20  may be an aspherical lens, and it is sandwiched between a first positioning body  44  and a second positioning body  45 . The first positioning body  44  is cap-shaped, and the second positioning body  45  is disc-shaped. The cap-shaped first positioning body  44  defines a receiving space to receive the condensing lens  20  therein, and the second positioning body  45  is thereafter mate with the side wall of the receiving space to position the condensing lens  20 . A resilient ring  51  may installed between the condensing lens  20  and the second positioning body  45  to further secure the condensing lens  20 . The first positioning body  44  is suitable to mate with the shell  40  with a resilient ring  50  disposed between the first positioning body  44  and the shell  40 . 
     The diverging lens  30  can be made of polycarbonate (PC) or cyclo-olefin polymer (COP). An annular flange is formed on the periphery of the diverging lens  30 , and it is sandwiched by a third positioning body  46  and a fourth positioning body  47 . The second positioners  43  are, for instance, used to clamp the flange of the diverging lens  30 . 
     In summary, the light module  10  is adjustable by adjusting the first positioners  41  and the adjusting elements  42 , and the second positioners  43  is used to adjust the level position of the diverging lens  30 , such that the light module  10 , the condensing lens  20  and the diverging lens  30  are coaxial. Furthermore, the diverging lens  30  is easily assembled and is suitable to reflect light without screen.