Patent Publication Number: US-2005133599-A1

Title: Image capture apparatus

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
      This Application claims priority to Taiwan Patent Application No. 92136513 entitled “Image Capture Apparatus,” filed on Dec. 23, 2003.  
     FIELD OF THE INVENTION  
      The present invention provides an image capture apparatus that is able to accommodate different sizes of objects to be scanned by adjusting the relative distance between a spacer and an image sensor module.  
     BACKGROUND OF THE INVENTION  
      A variety of optical components of image capture apparatus meet different functional requirements. The contact image sensors (CIS) are commonly used in thinner scanners or ones that require shorter response time. Due to the small depth of field of the CIS component, the CIS component has to be kept as close to the window glass as possible to ensure better scanning quality. Keeping the CIS component firmly in contact with the window glass is key to ensuring image quality.  
       FIG. 1   a  shows a side view of a prior art image sensor module. As shown in  FIG. 1 , spacers  103  are located between and firmly in contact with the window glass  105  and the image sensor module  101  to ensure the scanning quality. The object to be scanned  107  is disposed on the window glass  105  to maintain scanning quality during scanning. As shown in  FIG. 1   a , the spacers  103  are disposed on two sides of the image sensor module  101  while the window glass  105  is parallel to the image sensor  101 . In prior art modules, an elastic device (not illustrated) can be disposed above the image sensor module  101  to provide a force to maintain the spacer  103  firmly in contact with the image sensor module  101  and the window glass  105 . Details of such are found in Chinese Issued Patent 143606 or U.S. Pat. No. 6,611,364. It should be noted that the methods of placing elastic devices in the present invention can be but are not limited to those in the foregoing patents.  
       FIG. 1   b  shows a side view of the image sensor module of the prior art from another direction. Referring to  FIG. 1   b , readers would have a clearer understanding about the relative positions of the image sensor module  101 , the spacer  103 , the window glass and the object to be scanned  107 . The side views described thereafter are from the same viewpoint with  FIG. 2   b.    
      In prior art, when the object to be scanned  107  is something other than a document, such as a photo negative, it is disposed in a holder. Because of the thickness of the holder, this method degrades the scanning quality in the case of distance-sensitive contact image module. Solving this problem will improve the scanning quality and efficiency.  
     SUMMARY OF THE INVENTION  
      One aspect of the present invention is to provide an image capture apparatus that accommodates objects to be scanned of various sizes by adjusting the relative distance between a spacer and an image sensor module of the image capture apparatus.  
      The image capture apparatus of the present invention includes a window glass, an image sensor located below the window glass, a spacer disposed between and firmly in contact with the window glass and the image sensor, and an adjustment module connected to the image sensor. The adjustment module adjusts the relative distance between the spacer and the image sensor module to accommodate different objects to be scanned.  
      The present invention also includes another adjustment method wherein the relative distance between the spacer and the image sensor module is adjusted to accommodate different objects by utilizing the convexes and depressions in the spacer and the image sensor module. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1   a  shows a side view of a prior art image sensor module.  
       FIG. 1   b  shows a side view of the image sensor module of the prior art from another direction.  
       FIG. 2   a  shows a side view of the image capture apparatus of one embodiment of the present invention.  
       FIG. 2   b  shows a side view of the image capture apparatus of the embodiment of the present invention illustrated in  FIG. 2   a.    
       FIG. 3   a  shows a side view of the image capture apparatus of another embodiment of the present invention.  
       FIG. 3   b  shows a side view of the image capture apparatus illustrated in  FIG. 3   a.    
       FIG. 3   c  shows a schematic diagram of the location of the motor in the embodiment of  FIGS. 3   a  and  3   b.    
       FIG. 4   a  shows a side view of the image capture apparatus of another embodiment of the present invention.  
       FIG. 4   b  shows a side view of the image capture apparatus illustrated in  FIG. 4   a.    
       FIG. 5  shows a schematic diagram of how to switch scanning modes in the embodiment of  FIGS. 4   a  and  4   b.    
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      The present invention provides an image capture apparatus, wherein a relative distance between a spacer and an image sensor module of the image capture apparatus can be adjusted to apply to different objects to be scanned.  
       FIG. 2   a  shows a side view of the image capture apparatus in one embodiment of the present invention. As shown in  FIG. 2   a , the image capture apparatus of the present invention includes an image sensor  201 , a spacer  203 , the window glass  205  and the adjustment module  209 . The image sensor module  201  includes an image sensor component, for example, a compact image sensor, to capture images. During scanning, keeping the spacer  203  close to the window glass  205  and the image sensor module  201  is essential for ensuring scanning quality. The adjustment module  209  adjusts the relative distance between the image sensor module  201  and the spacer  203 . The image sensor module  201  includes an elastic device (not illustrated) providing a force to make the spacer  203  firmly in contact with the image sensor module  201  and the window glass  205 .  
      As shown in  FIG. 2   a , the image sensor module  201  is in a first scanning state and the spacer  203  is at a first position. The first object to be scanned  211  is put in the holder  213  first, and then the holder  213  is disposed on the window glass  205  for scanning. The first object  211  to be scanned here includes objects that require their own light source, (which can be disposed in the upper cap,) for example, photo negatives or transparencies.  
       FIG. 2   b  shows a side view of the image capture apparatus of  FIG. 2   a  wherein the image sensor module  201  is in a second scanning state and the spacer  203  is at a second position. The second object to be scanned  207  is directly disposed on the window glass  205  for scanning. The second object to be scanned  207  here includes objects that can be scanned by using reflection, such as a piece of paper or a photo.  
      Referring to  FIGS. 2   a  and  2   b , as the image sensor module switched between the first and the second scanning states, the adjustment module  209  adjusts the relative distance between the image sensor module  201  and the spacer for different objects. An exemplary adjustment module  209  includes a linkage-rod mechanism. For example a 4-rod linkage mechanism (two rods on each side; an even number of rods is chosen for stability). In other embodiments, the number of rods can be changed or the entire mechanism could be replaced with another mechanism that has a similar function. As shown in  FIG. 2   a , the image sensor module  201  is in the first scanning state and the rod of the adjustment module  209  is disposed at an angle “a” to the surface plane. The relative distance between the image sensor  201  and the spacer  203  is the first distance. When the user switches the image sensor module to the second scanning state, the transmission device (not illustrated) moves the image sensor module  201  to a specific position (for example, to one side of the image capture apparatus). After that, a rib device (not illustrated) on the housing pushes the rod to make the rod at an angle “b” to the surface plane. As shown in  FIG. 2   b , the image sensor module  201  is in the second scanning state and the rod of the adjustment module  209  is disposed at an angle “b” to the surface plane. The relative distance between the image sensor  201  and the spacer  203  is the second distance. If the angle “b” is greater than the angle “a,” the second distance is larger than the first distance. The relative distance between the image sensor module  201  and the spacer  203  can be adjusted for different objects by controlling the angle between the rods and the surface plane.  
       FIG. 3   a  shows a side view of the image capture apparatus of another embodiment of the present invention. The image sensor module  201  in  FIG. 3   a  is in the first scanning state.  FIG. 3   b  shows a side view of the image capture apparatus illustrated in  FIG. 3   a , wherein the image sensor module  201  in  FIG. 3   b  is in the second scanning state. In the embodiment in  FIGS. 3   a  and  3   b , a motor  301  rotates to adjust the linkage-rod mechanism of the adjustment module  209  (not illustrated in  FIGS. 3   a  and  3   b ) and thereby adjusts the relative distance between the image sensor module  201  and the spacer  203 .  
       FIG. 3   c  shows a schematic diagram of the location of the motor in the embodiment of  FIGS. 3   a  and  3   b . As shown in  FIG. 3   c , the motor  301  is connected to a pole  307  and the linkage rod of the adjustment module  209  includes a slot  309 . When the motor  301  is connected to the adjustment module  209 , the pole  307  is placed in the slot  309  exactly. Having the pole  307  contacting the sidewalls of the slot  309  allows the motor  301  to directly adjust the linkage rod. Alternatively, the motor  301  could be fixed on the image sensor module by appropriate arrangement of screws  303  and screw holes  305 .  
       FIGS. 4   a  and  4   b  show side views of the image capture apparatus of yet another embodiment of the present invention. In this embodiment, another method of adjusting the relative distance between the image sensor module  401  and the spacer  403  is provided. As shown in  FIG. 4   a , the image sensor module  401  is in the first scanning state with the first distance between the spacer  403  and the image sensor module  401 . The image sensor module  401  includes two first depressions  407  and two second depressions  409 , and the depth of the first depressions  407  is greater than the depth of the second depressions  409 . The spacer  403  includes two convex portions  405 . The convex portions  405  can slide into the first depressions  407  and the second depressions  409  respectively to adjust the relative distance between the image sensor module  401  and the spacer  403 .  
       FIG. 5  shows a schematic diagram of how to switch scanning modes in the embodiment of  FIGS. 4   a  and  4   b . When the image sensor module  401  is switched from the first scanning state ( FIG. 4   a ) to the second scanning state ( FIG. 4   b ), the transmission device (not illustrated) moves the image sensor module  401  to a specific position (for example, to one side of the image capture apparatus). Then, as shown in  FIG. 5 , the rib device on the housing pushes the spacer  403  to make the convex portions  405  slide out of the first depressions  407  and slide into the second depressions  409 . Then the relative distance between the image sensor module  401  and the spacer  403  is the second distance, and the second object to be scanned  207  can be disposed on the window glass  205  directly (as shown in  FIG. 4   b ). By the same approach, when the image sensor module  401  is switched from the second scanning state ( FIG. 4   b ) to the first scanning state ( FIG. 4   a ), the transmission device (not illustrated) moves the image sensor module  401  to another specific position (for example, another side of the image capture apparatus). The rib device on another side of the housing pushes the spacer  403  to make the convex portions  405  slide out of the first depressions  409  and slide into the second depressions  407  (not illustrated).  
      It should be noted that, numbers and positions of the convex portions  405 , the first depressions  407  and the second depressions  409  are not fixed and can be changed by users. In other embodiments, the convex portion  405  can be disposed on the image sensor module  401  as the first depressions  407  and the second depressions  409  are disposed in the bottom of the spacer  403  to perform the same function.  
      While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the discovered embodiments. The invention is intended to cover various modifications and equivalent arrangement included within the spirit and scope of the appended claims.