Abstract:
A light reflecting structure includes a light source and the at least one reflector. The reflector is disposed in the vicinity of the light source, and includes a plurality of reflecting regions and shading regions discretely arranged at a surface thereof to respectively reflect and shelter the light emitted from the light source, thereby generating a reflective light with substantially identical brightness.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to a light reflecting structure, and more particularly to a light reflecting structure for use in a light-emitting module of an image processing apparatus.  
       BACKGROUND OF THE INVENTION  
       [0002]     With increasing development, electronic products are more powerful and the sizes thereof are developed toward minimization. In addition to these requirements, the electronic product should have desired quality. For example, reflective scanners are widely used to for scanning opaque objects and processing the image information into analog or digital forms. Examples of the opaque objects include paper sheets, photographs, etc. In order to achieve better image quality, the components of the scanner should be properly selected and assembled. As known, the type of the light source and the brightness of the reflective light are major factors influencing the image quality of the scanner.  
         [0003]     A typical scanner comprises a light-emitting module in the lower housing thereof. The light-emitting module has therein several optical elements including a light source, a reflective mirror, a lens set, and a photoelectric conversion device such as a charge coupled device (CCD). When the scanner is operated, the light emitted by the light source is projected onto an opaque object placed on a scanning platform, which is typically a glass platform. The light reflected from the scanned object is incident into the light-emitting module and reflected by the reflective mirror. By means of the lens set, the light reflected from the reflective mirror is focused on the charge-coupled device (CCD) and converted into an electric signal in an analog or digital form.  
         [0004]     The light source used in the scanner is usually a linear cathode-ray tube lamp, which is parallel with the moving direction of the light-emitting module. Since the brightness at both sides of the linear cathode-ray tube lamp is weaker than that at the middle portion thereof, the light emitted by this light source fails to be evenly projected onto the scanned object. Therefore, the image quality of the scanned object is impaired.  
         [0005]     As the length of the light source is increased, the brightness of the light emitted from the light source becomes more uniform. However, the increase of the length is disadvantageous because the overall volume of the scanner is increased.  
       SUMMARY OF THE INVENTION  
       [0006]     It is an object of the present invention to provide light reflecting structure for use in a light-emitting module of an image processing apparatus so as to generate a reflective light with substantially identical brightness.  
         [0007]     In accordance with a first aspect of the present invention, there is provided a light reflecting structure for use in a light-emitting module of an image processing apparatus. The light reflecting structure comprises a light source and the at least one reflector. The reflector is disposed in the vicinity of the light source, and comprises a plurality of reflecting regions and shading regions discretely arranged at a surface thereof to respectively reflect and shelter the light emitted from the light source, thereby generating a reflective light with substantially identical brightness.  
         [0008]     In an embodiment, the reflector is disposed besides or under the light source.  
         [0009]     In an embodiment, the shading regions have gradual dense distributions from both sides to the middle portion of the reflector.  
         [0010]     In an embodiment, the shading regions have gradual area distributions from both sides to the middle portion of the reflector.  
         [0011]     In an embodiment, the shading regions can be gray scale images with gradual dense distributions from both sides to the middle portion of the reflector.  
         [0012]     In an embodiment, each of the shading regions has a stripe shape, a circular shape, a wavy shape, an elliptic shape, a triangular shape or a rectangular shape.  
         [0013]     In an embodiment, the light source is a linear cathode-ray tube lamp.  
         [0014]     In an embodiment, the reflector is a reflective sticker.  
         [0015]     In an embodiment, the shading regions are printed or paint-sprayed on the surface of the reflector.  
         [0016]     In an embodiment, the image processing apparatus is a scanner, a printing machine, a copying machine or a facsimile machine.  
         [0017]     In accordance with a second aspect of the present invention, there is provided a light reflecting structure for use in a light-emitting module of an image processing apparatus. The light reflecting structure comprises a light source and at least one reflector. The reflector is disposed in the vicinity of the light source, and comprises a plurality of reflecting regions and shading regions discretely arranged at a surface thereof to respectively reflect and shelter the light emitted from the light source, thereby generating a reflective light with substantially identical brightness. Especially, the shading regions have gradual dense distributions from both sides to the middle portion of the reflector.  
         [0018]     The above objects and advantages of the present invention will become more readily apparent to those ordinarily skilled in the art after reviewing the following detailed description and accompanying drawings, in which: 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]      FIG. 1  is a schematic view illustrating a light reflecting structure for use in a light-emitting module of a scanner according to a preferred embodiment of the present invention; and  
         [0020]     FIGS.  2 ( a ) and  2 ( b ) are schematic top views illustrating two examples of the reflector used in the light reflecting structure of  FIG. 1 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0021]     The present invention will now be described more specifically with reference to the following embodiments. It is to be noted that the following descriptions of preferred embodiments of this invention are presented herein for purpose of illustration and description only. It is not intended to be exhaustive or to be limited to the precise form disclosed.  
         [0022]     The present invention is directed to a light reflecting structure. Such a structure can be used in an image processing apparatus such as a scanner, a printing machine, a copying machine or a facsimile machine. The light generated from this light reflecting structure can be evenly projected onto the scanned objected.  
         [0023]     Referring to  FIG. 1 , a schematic view of a light reflecting structure according to a preferred embodiment of the present invention is shown. The light reflecting structure principally comprises a light source  11  and a reflector  12 . The light source  11  is disposed with a trench  101  of the light-emitting module  10 . In this embodiment, the light-emitting module  10  further comprises a reflective mirror, a lens set, and a photoelectric conversion device such as a charge coupled device (CCD). The functions of the reflective mirror, the lens set and the CCD element are similar to those described above. An example of the light source  11  used in the present invention is a linear cathode-ray tube lamp. The reflector  12  is disposed besides or under the light source  11 . The number of the reflector  12  can be more than one. When the scanner is operated, the light emitted by the light source  11  is reflected from the reflector  12  and then projected onto an opaque object placed on a scanning platform (not shown) above the light-emitting module  10 . The light reflected from the scanned object is incident into the light-emitting module  10  and reflected by the reflective mirror. By means of the lens set, the light reflected from the reflective mirror is focused on the CCD element and converted into an electric signal in an analog or digital form. In the embodiment of  FIG. 1 , the light source  11  is disposed above the trench  101  of the light-emitting module  10 , and the reflector  12  is attached to the bottom surface of the trench  101 . There is a gap between the light source  11  and the reflector  12 .  
         [0024]     Referring to  FIG. 2 ( a ), a schematic top view of a reflector is illustrated. The reflector  12  comprises a plurality of reflecting regions  120  and shading regions  121 , which are discretely arranged at the surface of the reflector  12 . The light emitted from the light source  11  may be reflected from the reflecting regions  120  but sheltered by the shading regions  121 . In other words, only the light incident to the reflecting regions  120  can be reflected and projected onto the scanned object, but the light incident to the shading regions  121  is absorbed and not reflected. In this embodiment, the shading regions  121  comprise several stripes along the width direction of the reflector  12 . Especially, these shading regions  121  have gradual dense distributions from both sides to the middle portion of the reflector  12 . In other words, the shading regions  121  are relatively denser at the middle portion and relatively sparser at both sides. Since the shading regions  121  at the middle portion are denser than those at the both sides, the light emitted from the middle portion of the light source  11  will be absorbed more. In this way, the brightness of the light from the light reflecting structure, which is a combination of the light source  11  and the reflector  12 , will be regulated to substantially identical so as to be uniformly projected on anywhere of the scanned object.  
         [0025]     A further embodiment of a reflector is illustrated in  FIG. 2 ( b ). The shading regions  121  comprise several segmental stripes along the length direction of the reflector  12  and have gradual dense distributions from both sides to the middle portion of the reflector  12 . The shading regions  121  may have any shapes so long as they have gradual dense distributions from both sides to the middle portion of the reflector  12 . For example, the shape of the shading regions  121  may be a circular shape, a wavy shape, an elliptic shape, a triangular shape or a rectangular shape. Alternatively, the shading regions  121  may have gradual area distributions from both sides to the middle portion of the reflector  12 . That is to say, the area of the shading region  12  for the middle portion is the relatively larger than that for each side.  
         [0026]     Furthermore, the density of the shading regions  121  is determined according to the intensity difference between the light emitted from the middle portion and the light emitted from the both side. The shading regions can be printed or paint-sprayed on the surface of the reflector. Alternatively, the shading regions can be gray scale images with gradual dense distributions from both sides to the middle portion of the reflector  12 .  
         [0027]     Since the shading regions of the reflector are capable of partially sheltering the light emitted from the light source and have gradual dense distributions from both sides to the middle portion thereof, the brightness of the light from the light reflecting structure is regulated to substantially identical. In such way, the light reflect from the light reflecting structure of the present invention can be evenly distributed on the scanned object. Therefore, the scanning quality will be largely enhanced without the need of increasing the length of the light source. In addition, the process for producing the shading portions on the surface of the reflector is simple and cost effective. The shape of the reflector can be arbitrary. Preferably, the reflector is a single-faced sticker in a shape of a long piece. The sticker is easily attached onto the bottom or side surface of the trench.  
         [0028]     While the invention has been described in terms of what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention needs not be limited to the disclosed embodiment. On the contrary, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims which are to be accorded with the broadest interpretation so as to encompass all such modifications and similar structures.