Light guide member, lighting apparatus using the light guide member, and method of fabricating the light guide member

Abstract

Provided are a light guide member, a lighting apparatus including the light guide member, and a method of fabricating the light guide member. The light guide member comprises: a body, which is formed as a transparent plate, including a first surface and a second surface facing the first surface; and a plurality of dimple type optical controllers formed beneath at least one of the first surface and the second surface and having reflective surfaces that reflect light proceeding between the first and second surfaces of the body toward at least one of the first and second surfaces.

1 . A light guide member comprising:
 a body, which is formed as a transparent plate, including a first surface and a second surface facing the first surface; and   a plurality of dimple type optical controllers formed beneath at least one of the first surface and the second surface and having reflective surfaces that reflect light proceeding between the first and second surfaces of the body toward at least one of the first and the second surfaces.   
   
   
       2 . The light guide member of  claim 1 , wherein one of the plurality of dimple type optical controllers comprises a cavity formed as a depression in the first surface, and the cavity includes a reflective surface and a bottom surface surrounded by the reflective surface. 
   
   
       3 . The light guide member of  claim 2 , wherein the cavity is formed as a truncated conical shape or a truncated pyramid shape. 
   
   
       4 . The light guide member of  claim 1 , wherein the body has an side facing light sources that supply light, and the reflective surface of the one of the plurality of dimple type optical controllers becomes larger as the optical controllers are further apart from the side. 
   
   
       5 . The light guide member of  claim 1 , wherein the body comprises side facing light sources that supply light, and the cavity of the one of the plurality of dimple-type optical controllers has an asymmetrical structure, which extends in a direction perpendicular to a propagating direction of the light. 
   
   
       6 . The light guide member of  claim 2 , wherein the cavity comprises a bottom surface that is parallel with at least one of the first surface and the second surface of the body. 
   
   
       7 . The light guide member of  claim 4 , wherein a length of the cavity of the one of the plurality of dimple-type of the optical controllers is proportional to the distance of the one of the plurality of dimple-type optical controllers from the side. 
   
   
       8 . The light guide member of  claim 1 , wherein the light guide member is formed of an elastic material. 
   
   
       9 . The light guide member of  claim 8 , wherein the elastic material comprises polydimethylsiloxane. 
   
   
       10 . A lighting apparatus comprising:
 a body, which is formed as a transparent plate, having a first surface and a second surface facing the first surface;   a plurality of dimple type optical controllers formed beneath at least one of the first surface and the second surface and having reflective surfaces that reflect light proceeding between the first and second surfaces of the body toward at least one of the first and the second surfaces; and   light sources disposed on a first side of the body which irradiate the light between the first surface and the second surface.   
   
   
       11 . The lighting apparatus of  claim 10 , further comprising:
 a reflective surface disposed on a second side of the body, facing the light sources.   
   
   
       12 . The lighting apparatus of  claim 10 , wherein one of the plurality of dimple type optical controllers is a cavity formed as a depression in the first surface, and the cavity comprises a reflective surface and a bottom surface surrounded by the reflective surface. 
   
   
       13 . The lighting apparatus of  claim 12 , wherein the cavity of the one of the plurality of dimple type optical controllers is formed as a truncated conical shape or a truncated pyramid shape. 
   
   
       14 . The lighting apparatus of  claim 10 , wherein the body comprises an side facing the light sources that supply light, and the reflective surface of the one of the plurality of dimple type optical controllers becomes larger as the optical controllers are further apart from the side. 
   
   
       15 . The lighting apparatus of  claim 10 , wherein the body comprises an side facing light sources that supply light, and the cavity of the one of the plurality of dimple type optical controllers comprises an asymmetrical structure, which extends in a direction perpendicular to a propagating direction of the light. 
   
   
       16 . The lighting apparatus of  claim 10 , wherein the cavity comprises a bottom surface that is parallel with at least one of the first surface and the second surface of the body. 
   
   
       17 . The lighting apparatus of  claim 14 , wherein a length of the cavity of the one of the plurality of dimple type optical controllers is increased, as the optical controllers are further apart from the side. 
   
   
       18 . The lighting apparatus of  claim 10 , wherein the light guide member is formed of an elastic material. 
   
   
       19 . The lighting apparatus of  claim 18 , wherein the elastic material comprises polydimethylsiloxane. 
   
   
       20 . A method of fabricating a light guide member, the method comprising:
 forming a plurality of protrusion molds on a template having a flat surface, each of the plurality of protrusion molds including a top surface that is wider than a bottom and a side surface under the top surface and inclined toward the top surface;   forming a transparent half-processed light guide member having a cross-section corresponding to the plurality of protrusion molds by applying a transparent material on the template on which the plurality of protrusion molds are formed; and   separating the transparent half-processed light guide member from the template and the plurality of protrusion molds so as to form the light guide member, which includes a first surface, a second surface facing the first surface, and a plurality of dimple type optical controllers, corresponding to the protrusion molds, in the first surface, wherein each of the plurality of dimple type optical controllers includes a reflective surface corresponding to the inclined side surface of each of the plurality of protrusion molds.   
   
   
       21 . The method of  claim 20 , wherein the forming of the plurality of protrusion molds comprises:
 forming a light blocking mask, having openings corresponding to the plurality of protrusion molds, on the template;   forming a photosensitive layer for forming the plurality of protrusion molds on the template to cover the light blocking mask;   irradiating light to the light blocking mask to form exposure regions corresponding to the shapes of the plurality of protrusion molds in the photosensitive layer; and   developing the photosensitive layer to obtain the plurality of protrusion molds from the exposure regions.   
   
   
       22 . The method of  claim 21 , wherein the photosensitive layer is exposed to diffused light that is incident to a bottom surface of the template. 
   
   
       23 . The method of  claim 21 , wherein the photosensitive layer is exposed to parallel light that is incident to the bottom surface of the template in a direction inclined with respect to the bottom surface of the template. 
   
   
       24 . The method of  claim 20 , wherein the light guide member is formed of polydimethylsiloxane (PDMS).