Abstract:
An illumination lamp includes a housing, light source, a light reflecting device and a light path conversion device. The housing defines a light emitting window therein. The light source is disposed in the housing. The light reflecting device is disposed in the housing and has a reflecting surface. The light path conversion device is disposed in the housing. The light path conversion device is configured for converting light rays emitted from the light source into parallel light rays and directing the parallel light rays toward the light reflecting surface of the light reflecting device. The light reflecting device reflects the parallel light rays out of the housing via the light emitting window.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present invention relates generally to an illumination lamp, and more particularly to an illumination lamp capable of evenly illuminating a large area. 
         [0003]    2. Description of Related Art 
         [0004]    Presently, LEDs are preferred for use in non-emissive display devices than CCFLs (cold cathode fluorescent lamp) due to their high brightness, long lifespan, and wide color range. However, the LED is a point light source, and an emitting surface thereof is usually hemispherical. Intensity of a light field of the LED decreases gradually and outwardly along a radial direction thereof. The intensity of the light field of the LED is uneven, being strong at a center of the light field and weak at a periphery of the light field. 
         [0005]    Therefore, it is desirable to provide an illumination lamp to overcome the above-mentioned shortcoming. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    Many aspects of the present embodiments can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present embodiments. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
           [0007]      FIG. 1  an isometric view of an illumination lamp according to a first embodiment of the present invention. 
           [0008]      FIG. 2  is a cross-sectional view of the illumination lamp of  FIG. 1 , taken along line II-II thereof. 
           [0009]      FIG. 3  is an isometric view of an illumination lamp according to a second embodiment of the present invention. 
           [0010]      FIG. 4  is a cross-sectional view of the illumination lamp of  FIG. 3 , taken along line IV-IV thereof. 
           [0011]      FIG. 5  is an exploded view of an illumination lamp according to a third embodiment of the present invention. 
           [0012]      FIG. 6  is an assembled isometric view of the illumination lamp of  FIG. 5 . 
           [0013]      FIG. 7  is a cross-sectional view of the illumination lamp of  FIG. 6 , taken along line VII-VII thereof. 
           [0014]      FIG. 8  is an isometric view of a reflecting device of the illumination lamp of  FIG. 6 . 
           [0015]      FIG. 9  is an exploded view of the reflecting device of  FIG. 8 . 
           [0016]      FIG. 10  is an isometric view of an illumination lamp according to a fourth embodiment of the present invention. 
           [0017]      FIG. 11  is a cross-sectional view of the illumination lamp of  FIG. 10 , taken along line XI-XI thereof. 
           [0018]      FIG. 12  is an exploded view of the illumination lamp of  FIG. 10 . 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    Referring to  FIGS. 1-2 , an illumination lamp  10  according to an exemplary embodiment of the present invention includes a cylindrical housing  11 , an LED light source  12 , a light path conversion device  13  and a light reflecting device  14 . 
         [0020]    The light path conversion device  13  includes a protrusion  130  and a paraboloid  132  recessed in the protrusion  130 . The protrusion  130  is column-shaped and extends axially and inwardly from an axial end  111  of the housing  11 . The protrusion  130  has a central axis  133  coaxial with a central axis of the housing  11 . The protrusion  130  has a near end connected with the axial end  111  of the housing and a distal free end. The paraboloid  132  is defined in the distal free end of the protrusion  130 . An opening  131  of the paraboloid  132  faces another axial end  112  of the housing  11 . The LED light source  12  is located at a focus point of the paraboloid  132  and faces the paraboloid  132 . 
         [0021]    The light reflecting device  14  is a rectangle-shaped plate and has a light reflecting surface  141  facing the LED light source  12 . The light reflecting device  14  is disposed in the housing  11  and adjacent to the another axial end  112  of the housing  11 . The paraboloid  132  and the light reflecting device  14  are disposed at a left side and a right side of the LED light source  12 , respectively. A center of the light reflecting device  14  is disposed at the central axis  133  of the paraboloid  132 . The light reflecting device  14  is inclined at an acute angle  0  with respect to the central axis  133  of the paraboloid  132 . An outer peripheral surface  113  of the housing  11  defines a light emitting window  114  adjacent to the light reflecting device  14 . The light reflecting surface  141  of the light reflecting device  14  faces the light emitting window  114 . 
         [0022]    The light rays emitted by the LED light source  12  which is disposed at the focus point of the paraboloid  132  travel in a direction from the LED light source  12  toward the paraboloid  132 . After the light rays are reflected by the paraboloid  132 , the originally radiate light rays from the LED light source  12  are converted into parallel light rays by the paraboloid  132  and then travel along a direction from the paraboloid  132  toward the light reflecting device  14 . Then, the parallel light rays are reflected by the light reflecting device  14  and redirected toward the light emitting window  114 . The parallel light rays continue their ways out of the housing  11  via the light emitting window  1   14 . 
         [0023]    The paraboloid  132  redirects the non-parallel light rays emitted by the LED light source  12  into the parallel light rays toward the light reflecting device  14 . Thus, the LED light source  12  which is a point light source is transformed to a surface light source and the illumination lamp  10  is capable of evenly illuminating objects through the light emitting window  114 . 
         [0024]      FIGS. 3-4  show an illumination lamp  20  according to a second alternative embodiment. The difference lies in the light reflecting device  24 . In this alternative embodiment, the light reflecting device  24  is ladder-shaped and includes a plurality of parallel rectangle-shaped reflectors  240  disposed in the housing  21 . The reflectors  240  are offset from each other, with a distance between each reflector  240  and the light emitting window  214  gradually decreased along the central axis  233  from the first axial end  211  from which the protrusion  230  is formed towards the opposite second axial end  212  of the housing  21 . Each reflector  240  is inclined at an acute angle  0  with respect to a central axis  233  of the paraboloid  232 . Each reflector  240  has a reflecting surface  241  facing the light emitting window  214 . The parallel light rays redirected by the paraboloid  232  are emitted outwards through the light emitting window  214  via the reflectors  240 . 
         [0025]    Referring to  FIGS. 5-7 , an illumination lamp  30  according to a third embodiment of the present invention includes a cylindrical-shaped housing  31 , a light reflecting device  34 , a heat pipe  36 , a heat sink  35 , a light path conversion device  33  and an LED light source  32 . 
         [0026]    The housing  31  has a circular and flat mounting surface  315  at an axial end  311  thereof. A center of the mounting surface  315  defines a mounting recess  316  thereby forming a protrusion  317  in the housing  31 . 
         [0027]    The heat sink  35  includes a pole  351  and a plurality of circular fins  352  surrounding the pole  351  and spaced from each other. The heat sink  35  is disposed at an outer side of the housing  31  and an end  353  of the pole  351  is inserted into the mounting recess  316  of the mounting surface  315  and fixed on the mounting surface  315  via a screw  333 . 
         [0028]    The light path conversion device  33  is a cup-shaped light reflector and defines a paraboloid  332  at an inner surface thereof. The light path conversion device  33  is mounted to the protrusion  317  of the housing  31  and an opening  331  of the paraboloid  332  faces the light reflecting device  34 . The screw  333  extends successively through a center of the light path conversion device  33  and the protrusion  317  and is eventually connected with the pole  351  of the heat sink  35 . 
         [0029]    The heat pipe  36  is curved and includes an evaporator section  361 , a condenser section  362  and an adiabatic section  363 . The evaporator section  361  and the condenser section  362  are disposed at two opposite ends of the heat pipe  36 . The adiabatic section  363  is disposed between the evaporator section  361  and the condenser section  362 . The adiabatic section  363  is U-shaped and includes a first vertical portion  365  connected with the condenser section  362 , a second vertical portion  366  connected with the evaporator section  361  and a lateral portion  367  disposed between the first vertical portion  365  and the second vertical portion  366 . The evaporator section  361  is disposed in the housing  31 . A free end  364  of the evaporator section  361  is located at a focus point of the paraboloid  332  and faces the opening  331  of the paraboloid  332 . The LED light source  32  is disposed at the free end  364  of the evaporator section  361 , whereby the LED light source  32  is disposed at the focus point of the paraboloid  332 . The lateral portion  367  of the adiabatic section  363  and the condenser section  362  extend through the fins  352  of the heat sink  35  whereby the lateral portion  367  of the adiabatic section  363  and the condenser section  362  are connected with the heat sink  35 . 
         [0030]    The light reflecting device  34  is received in the housing  31  and located at the another axial end  312  of the housing  31  far away from the heat sink  35 , whereby the light reflecting device  34  and the light path conversion device  33  are disposed at two opposite sides of the LED light source  32 . An outer peripheral surface  313  of the housing  31  defines a light emitting window  314  adjacent to the light reflecting device  34 . 
         [0031]    Referring to  FIGS. 8-9 , the light reflecting device  34  includes a driving reflector  341 , a plurality of follower reflectors  342  parallel to the driving reflector  341 , a first connecting bar  343 , a second connecting bar  344 , a third connecting bar  345 , a fourth connecting bar  346 , a first supporting pole  347 , a second supporting pole  348 , a third supporting pole  349  and a rotating pole  340 . 
         [0032]    The driving reflector  341  and each of the follower reflectors  342  is rectangle-shaped and includes a light reflecting surface  3411 ,  3421 , a first side surface  3412 ,  3422  and a second side surface  3413 ,  3423 . The first side surface  3412 ,  3422  and the second side surface  3413 ,  3423  are opposite and disposed at a left side and a right side of the light reflecting surface  3411 ,  3421 . The light reflecting surfaces  3411 ,  3421  of the driving reflector  341  and the follower reflectors  342  cooperatively form a light reflecting surface of the light reflecting device  34 . The light reflecting surface of the light reflecting device  34  faces the light emitting window  314 . 
         [0033]    The first connecting bar  343  and the third connecting bar  345  are disposed at a left side of the light reflecting device  34  and pivotally connected with each of the first side surfaces  3412 ,  3422  of the driving reflector  341  and the follower reflectors  342 . The second connecting bar  344  and the fourth connecting bar  346  are disposed at a right side of the light reflecting device  34  and pivotally connected with each of the second side surfaces  3413 ,  3423  of the driving reflector  341  and the follower reflectors  342 . The fourth connecting bar  346  and the driving reflector  341  have a pivotal connection point  3404  at the second side surfaces  3413  of the driving reflector  341 . 
         [0034]    Each of the first supporting pole  347 , the second supporting pole  348  and the third supporting pole  349  includes a body portion  3472 ,  3482 ,  3492  and a head portion  3471 ,  3481 ,  3491 . The rotating pole  340  includes a body portion  3402 , a head portion  3401  and a crank portion  3403 . The crank portion  3403  of the rotating pole  340  extends radially and outwardly from an outer peripheral surface of the body portion  3402  of the rotating pole  340 . 
         [0035]    The first supporting pole  347  and the rotating pole  340  are symmetrically disposed at a left side and a right side of the driving reflector  341 , respectively. The body portion  3472  of the first supporting pole  347  extends successively through the housing  31  and the first connecting bar  343  and is pivotally connected with the driving reflector  341 . The head portion  3471  of the first supporting pole  347  resists on the outer peripheral surface  313  of the housing  31 . The body portion  3402  of the rotating pole  340  extends successively through the housing  31  and the second connecting bar  344  and is pivotally connected with the driving reflector  341 . The head portion  3401  of the rotating pole  340  resists on the outer peripheral surface  313  of the housing  31 . The crank portion  3403  of the rotating pole  340  is pivotally connected with the driving reflector  341  at the pivotal connection point  3404 . 
         [0036]    The second supporting pole  348  and the third supporting pole  349  are symmetrically disposed at a left side and a right side of the follower reflector  342 , respectively. The body portion  3482  of the second supporting pole  348  extends successively through the housing  31  and the first connecting bar  343  and is pivotally connected with the follower reflector  342 . The head portion  3481  of the second supporting pole  348  resists on the outer peripheral surface  313  of the housing  31 . The body portion  3492  of the third supporting pole  349  extends successively through the housing  31  and the second connecting bar  344  and is pivotally connected with the follower reflector  342 . The head portion  3491  of the third supporting pole  349  resists on the outer peripheral surface  313  of the housing  31 . 
         [0037]    When the rotating pole  340  is rotated under an external force, the crank portion  3403  of the rotating pole  340  can make the driving reflector  341  rotate with the rotating pole  340 , whereby the third connecting bar  345  and the fourth connecting bar  346  can move parallel to the first connecting bar  343  and the second connecting bar  344 . The movement of the third connecting bar  345  and the fourth connecting bar  346  can make the follower reflectors  342  rotate at a same rotating speed as the driving reflector  341 . Thus, the angle  0  between the light reflecting device  34  and the central axis  334  of the paraboloid  332  can be adjusted to change an incident angle of the light rays at the light reflecting surface of the light reflecting device  34 . Therefore, the direction of the light rays emitted from the illumination lamp  30  can be conveniently adjusted to satisfy various luminous requirements. The heat generated by the LED light source  32  can be transferred to the heat sink  35  via heat pipe  36  and dissipated into an outer atmosphere via the heat sink  35 . 
         [0038]    Referring to  FIGS. 10-12 , an illumination lamp  40  according to a fourth embodiment of the present invention includes a cylindrical-shaped housing  41 , a light reflecting device  44 , a heat sink  45 , a light path conversion device  43  and an LED light source  42 . The light path conversion device  43  is a biconvex lens. The biconvex lens is disposed in the housing  41 . An optical axis  433  of the biconvex lens is coaxial with the central axis of the housing  41 . A center of the protrusion  417  is disposed at a right focus point of the biconvex lens. The LED light source  42  is disposed at the center of the protrusion  417  and faces the biconvex lens, whereby the LED light source  42  is disposed at the right focus point of the biconvex lens. The light reflecting device  44  and the LED light source  42  are disposed at a left side and a right side of the biconvex lens. The light reflecting device  44  is inclined at an angle θ with respect to the optical axis  433  of the biconvex lens and the light reflecting surface of the light reflecting device  44  faces the light emitting window  414 . 
         [0039]    The light rays emitted by the LED light source  42  travel in a direction from the LED light source  42  toward the biconvex lens. After the light rays pass through the biconvex lens, the light rays are transformed to parallel light rays and then continue to travel toward the light reflecting device  44 . The parallel light rays are reflected by the light reflecting device  44  and redirected toward the light emitting window  414 . The light rays continue their ways out of the housing  41  via the light emitting window  414 . Since the LED light source  42  is disposed at the protrusion  417  of the housing  41 , the heat generated by the LED light source  42  can be transferred to the heat sink  45  via the protrusion  417  and dissipated into the outer atmosphere via the heat sink  45 . 
         [0040]    It is believed that the present embodiments and their advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the examples hereinbefore described merely being preferred or exemplary embodiments of the invention.