Abstract:
The invention, disclosing a light-path device of curved-surface mirror, is a light-path device that is designed in an optical scanner. By an appropriate arrangement of the inter-relationship between the curved-surface mirror and the light-path module in its light-path route, the length of the light-path route may thereby be adjusted, such that there are different lengths of light-path route according to the different positions where the curved-surface mirror is located without the limitations of the size of the scanned object or the physics characteristics of the photoelectric conversion device itself. The invention includes curved-surface mirror, light source, light-path module, light-focusing device, and photoelectric conversion device. The light-path module further includes reflection device and light-focusing device. The reflection device is constituted of plural reflection mirrors. The light-focusing device is lens. The curved-surface mirror is belonged to a curved-surface mirror of convex type or concave type.

Description:
FIELD OF THE INVENTION  
         [0001]    The invention relates to a light-path device of curved-surface mirror, especially to a light-path device that has curved-surface mirror and is arranged in an optical scanner for adjusting the total light-path length in the light-path device.  
         BACKGROUND OF THE INVENTION  
         [0002]    Accordingly, the application principle of an optical scanner is that a light beam is reflected through a light-path device and formed into an image by the lens and, a charge-coupled device is further applied to convert the light signal into digital signal capable of being memorized and processed by computer but, since the limitation of a certain light-path&#39;s length required to form the desired image, so the light has to be reflected several times by plural pieces of reflection mirror in the light-path device, then its dimension can be reduced effectively. Therefore, in the light-path device, the number, the size, and the inter-corresponding arrangement and position of the reflection mirror will decide the light-path route of a light-path device and, in the meantime, in matching with the functions of magnification and reduction of a lens, the length of the light-path route is then determined.  
           [0003]    Please refer to FIG. 1, which is a three-dimensional structural illustration for a flatbed optical scanner typically seen in current market. Mainly, a object supporting glass  15  is arranged on the upper side surface of an outer shell  11  of a scanner  1  for placing a reflective object  10 . A light-path device  2  brought along by a driving device  13  for proceeding a linear motion along the direction of a guiding rod  14  in the hollow outer shell  11 , such that an image scanning job is executed on the reflective object  10  placed on the object supporting glass  12 .  
           [0004]    Please refer to FIG. 2, which is an illustration for the light-path route in a flatbed optical scanner according to the current prior arts. The route of the light-path is designed in the light-path device  2 , which is comprised of light source  20 , light-path module  21 , and charge-coupled device  22 . The light-path module  212  includes three pieces of reflection mirror  211 ,  212 ,  213 , and a lens  214 . The light of the light source  20  is penetrated through the object supporting glass  16  and irradiated upon the reflective object  10 , and the irradiated reflective object  10  then the light is reflected sequentially by the first reflection mirror  211 , the second reflection mirror  212 , and the third reflection mirror  213 , which finally reflects the light to a lens  214 , from which the focused light is further irradiated to a charge-coupled device  22 .  
           [0005]    Same as the prior technique described thereinbefore, in the optical system applied in a scanner, in order to reduce the object plane to be able to be imaged on the photoelectric device, the functions of the lens&#39; magnification and reduction are applied but, however, because of the limitation of the factors of specification and physics of the lens itself during manufacture and the factor of the size of the scanned object itself, therefore, the length of the light-path route must be designed long enough to make the image of the entire scanned object formed smoothly on the lens so, if we can improve the light-path device by adjusting its light-path route, then the invention is indeed an innovative breakthrough in current technique filed.  
         SUMMARY OF THE INVENTION  
         [0006]    According to the shortcomings of above prior arts, the invention proposes an innovative design of light-path device including curved-surface mirror design. The main objective of the invention is to provide a light-path device of curved-surface, wherein the device is arranged in an optical scanner. Appropriately arranging the inter-relational position of the curved-surfaced mirror with other reflection mirror or photoelectric conversion device in the light-path route, the length of the light-path route can be thereby adjusted, such that different lengths of light-path route will be determined according to the different positions of curved-surface mirror in the light-path route, and a document is scanned at an appropriate position that is pre-designed without the limitations of the size of the scanned document or the photoelectric conversion device itself.  
           [0007]    The invention includes curved-surface mirror, light source, light-path module, light-focusing device, and photoelectric conversion device. The light-path module includes reflection device and light-focusing device, wherein the reflection device is comprised of plural reflection mirrors, and the light-focusing device may be a lens. The light source provides the light needed in a scanning procedure, and the reflection mirrors sequentially reflect the light penetrating through the transparent supporting glass and reflected from the object to reach a predetermined length of reflective line-path, while the lens may receive the reflective light reflected from the reflection mirrors and focus it into image, and the photoelectric conversion device then receives the light focused as an image by the lens and converts it into electric signal.  
           [0008]    The relation between the system&#39;s magnification ratio and the subsystem&#39;s magnification ratio is applied such that, in the light-path design of the curved-surface mirror and the light-path of the light-path module, the positions between the curved-surface mirror and the light-path module may decide the value of the system magnification, so thereby is the total length of the light-path route determined.  
           [0009]    In a preferable embodiment, a convex mirror is designed between the object and the light-path module for adjusting the light-path length between them.  
           [0010]    In another preferable embodiment, a concave mirror is designed between the object and the light-path module for adjusting the light-path length between them.  
           [0011]    In a further preferable embodiment, a concave mirror or a convex mirror is designed between the light-path module and the photoelectric conversion device for adjusting the light-path length between them.  
           [0012]    In a further another preferable embodiment, a concave mirror and a convex mirror are respectively designed between the object and the light-path module, and between the light-path module and the photoelectric conversion device for adjusting the light-path lengths among them.  
           [0013]    For your esteemed members of reviewing committee to further understand and recognize the objective, the characteristics, and the functions of the invention, a detailed description in matching with Corresponding drawings are presented as the following: 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]    [0014]FIG. 1 is a three-dimensional structural illustration for a flatbed optical scanner according to the current prior arts.  
         [0015]    [0015]FIG. 2 is an illustration for a light-path route in a flatbed optical scanner according to the current prior arts.  
         [0016]    [0016]FIG. 3 is a first preferable embodiment according to the invention.  
         [0017]    [0017]FIG. 4 is a second preferable embodiment according to the invention.  
         [0018]    [0018]FIG. 5 is a third preferable embodiment according to the invention.  
         [0019]    [0019]FIG. 6 is a fourth preferable embodiment according to the invention.  
         [0020]    [0020]FIG. 7 is a fifth preferable embodiment according to the invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0021]    The invention discloses a light-path device, of curved-surface mirror, arranged in a light-path module, wherein a light-path route is designed and adjusted, through the variation of different light-path positions for the curved-surface mirror to focus or disperse the optical image, the entire light-path route is further adjusted. The variation of the execution pattern of the invention is opulent, not only may the design keep the original reflection function in the light-path route, but also may an innovative technique be provided for changing the length of the entire light-path route, such that an impossibly breaking-through problem of the prior arts is solved, and thereby is the quality of the scanned image further improved.  
         [0022]    The principle of the invention is to apply the design of an image magnification ratio (M) in the light-path. The magnification ratio of the image reflected and focused by the reflection mirrors and the lens is matched with the position of the curved-surface mirror for adjusting the magnification ratio, such that the reflection, the focus, and the photoelectric conversion of the image may be completed smoothly. For the magnification ratio of an ordinary document, it must consider the size (Wd) of the surface of the document, the size (Wc) of the sensing cell of the photoelectric conversion device, and the diffraction limitation of the lens design, all which may be expressed as following formula:  
         Magnification= Q (image size)/ P (object size)= Hi (image height)/ Ho (object height)=( Nc*Wc )/ Wd    
         [0023]    Wherein, Nc is the number applied by the sensing cell of the photoelectric conversion device, so the system magnification ratio (M system ) may be designed by a manner of separation system; namely, a formula may be described as the following:  
           M   system   =M 1 *M 2 *M 3 * . . . Mn    
         [0024]    Wherein, n is the number of the separation system. In other words, the magnification ratio (M system ) of a major system may be designed as the product of the magnification ratios of several separated sub-systems; in other words, asides from the magnification ratio of the lens&#39; object system, other sub-system&#39;s magnification ratio may be found, and the magnification ratio of the sub-system is adjustable so, adjusting the magnification ratio of the sub-system is to adjust the magnification ratio of the major system, and the design of the entire light-path route is further determined. The curved-surface mirror applied in the invention may be responsible for the character on adjusting the magnification ratio of the sub-system to further adjust the magnification ratio of the entire major system and, by arranging different positions of the curved-surface mirrors, the functions of the convergence (reduction) or the dispersion (magnification) to the image may be achieved such that, relatively, the design of the curved-surface mirror of the invention has extensive flexibility without the limitation posed by the diffraction extremity of the lens itself, so it can be designed as the following:  
         
       M 
       system 
       =M 
       lens 
       *M 
       curved-surface mirror  
     
         [0025]    In such way, the adjustment of the light-path route for the reflection, the focus, and the photoelectric conversion to the image by an entire optical scanner is achieved. For convenient description, in the following embodiment, the reflection device (including plural reflection mirrors) and the lens are regarded as a sub-system M lens ; that is, if the plural reflection mirrors and the lens are assumed as a light-path module, then this light-path module may be designed correspondingly with the curved-surface mirror, and the light-path modules for different magnification ratios may then be matched correspondingly with the curved-surface mirrors of different magnification ratios.  
         [0026]    Please refer to FIG. 3, which is a first preferable embodiment according to the invention, which is a light-path device of curved-surface mirror. Designing curved-surface mirror in the light-path of a scanner, the length of the light-path route in the light-path device of a scanner may be adjusted, wherein the light-path device  3  includes light-source device (light source  30 ), light-path module  31 , and photoelectric conversion device  32  (may be a CCD), and the light-path module  31  further includes reflection device (comprised of reflection mirrors  311 ,  312 ,  313 ) and light-focusing device (lens  314 ). The light source  30 , providing a light needed by the scanning procedure, irradiates the light penetrating through the transparent supporting glass  16  and incident upon an object  10 ; the reflection mirrors  311 ,  312 ,  313  sequentially reflect the light reflected from the object  10  placed on the transparent supporting glass  16  to reach a predetermined length of reflective light-path, while the lens  314 , a light-focusing device capable of focusing light into image, receives the light reflected from the reflection mirror  313  and focuses it into an image and, at last, the photoelectric conversion device  32  receives the light of the image focused by the lens  314  and converts it into electric signal.  
         [0027]    The characteristic of the invention is that a curved-surface mirror  33  is designed between the light-path module  31  and the object  10 , or a curved-surface mirror  34  is designed between the light-path module  31  and the photoelectric conversion device  32  and, in the meantime, one or two of the curved-surface mirrors  33 ,  34  may be chosen, such that a design related to the system magnification ratio M system =M lens *M curved-surface mirror  described thereinbefore may be fulfilled. The light-path module  31  is designed as a sub-system containing the lens  314 , and the curved-surface mirror  33  or the curved-surface mirror  34  is designed as another sub-system (only one of the curved-surface mirror  33  or the curved-surface mirror  34  is applied), then M system =M light-path module  * M curved-surface mirror 33  or M system =M light-path module  * M curved-surface mirror 34 , wherein the M light-path module  is the M lens  described thereinbefore. Or, when the curved-surface mirror  33  is regarded as a first sub-system and the curved-surface mirror  34  is regarded a second sub-system (i.e., the curved-surface mirror  33  and the curved-surface mirror  34  are applied simultaneously), M system =M light-path module  * M curved-surface mirror 33  * M curved-surface mirror 34 , wherein the M light-path module  is the M lens  described thereinbefore.  
         [0028]    Please refer to FIG. 4, which is the second preferable embodiment according to the invention. As shown in FIG. 4, this preferable embodiment designs the curved-surface mirror  330  between the object  10  and the light-path module  31 , then the light progressing from the object  10  toward the light-path module  31  will be focused (shrunk) into the light-path module  31 . In other words, through the curved-surface mirror  330 , the image may be irradiated into the light-path module  31  within a shorter light-path route, so the length of the light-path will be shorter by comparing with that there is no curved-surface mirror  330 . In other words, under the situation that the size of the object  10  is not changed, the curved-surface mirror  330  may adjust the length of the light-path route between the object  10  and the light-path module  3   1 , wherein the curved-surface mirror  330  is a convex mirror (i.e., its convex surface is toward the object  10 ).  
         [0029]    Please refer to FIG. 5, which is a third preferable embodiment according to the invention. As shown in FIG. 5, this preferable embodiment is roughly similar to that shown in FIG. 4. However, the curved-surface mirror  331  is a concave mirror (i.e., its concave surface is toward the object  10 ). Therefore, any case of convex mirror or concave mirror may all be applied in the invention. By changing the position of the curved-surface mirror in the light-path route, it may relatively change the light-path length between the object  10  and the light-path module  31 . Of course, the position in either case of the curved-surface mirror  330  in FIG. 4 or the curved-surface mirror  331  in FIG. 5 may be designed according to the light-path length of actual need. The light-path route summarized from FIG. 3 through FIG. 5 is described sequentially as the following: light-source device (light source  30 )=&gt;object  10 =&gt;curved-surface mirror (curved-surface mirror  330  or curved-surface mirror  331 )=&gt;reflection device (reflection mirrors  311 ,  312 ,  313 )=&gt;light-focusing device (lens  314 )=&gt;photoelectric conversion device  32  (CCD).  
         [0030]    Please refer to FIG. 6, which is the fourth preferable embodiment of the invention. As shown in FIG. 6, this preferable embodiment designs a curved-surface mirror  340  between the light-path module  31  and the photoelectric conversion device  32 , then the light progressing from the light-path module  31  toward the photoelectric conversion device  32  will be dispersed (magnified) to the photoelectric conversion device  32 , so the light-path length will be shortened relatively by comparing with there is no curved-surface mirror  340 . Namely, under the situation that the size of the photoelectric conversion device  32  is not changed, the curved-surface mirror  340  may adjust the length of the light-path route from the light-path module  31  to the photoelectric conversion device  32 . In other words, the curved-surface mirror  340  may irradiate the image into the photoelectric conversion device  32  with a shorter light-path length, such that the dispersed image will be processed by a photoelectric conversion within the photoelectric conversion device  32 . By changing the position of the curved-surface mirror  340  in the light-path route, it may relatively change light-path length between the photoelectric conversion device  32  and the light-path module  31 . The category of the curved-surface mirror  330  may be a convex mirror or a concave mirror. The light-path route summarized from FIG. 3 through FIG. 6 is described sequentially as the following: light-source device (light source  30 )=&gt;object  10 =&gt;reflection device (reflection mirrors  311 ,  312 ,  313 )=&gt;light-focusing device (lens  314 )=&gt;curved-surface mirror (curved-surface mirror  340 )=&gt;photoelectric conversion device  32  (CCD).  
         [0031]    Please refer to FIG. 7, which is the fifth preferable embodiment of the invention. As shown in FIG. 7, a curved-surface mirror  332  is designed between the light-path module  31  and the photoelectric conversion device  32 , and another curved-surface mirror  341  is designed between the light-path module and the scanned object  10  and, in such design, the size between the light-path module  31  and the photoelectric conversion device  32  and the size between the light-path module  31  and the scanned object  10  may be adjusted simultaneously and, on the other hand, the curved-surface mirror  332  may converge the image to make the photo-image, of the scanned object  10 , after being converged, be then irradiated into the light-path module  31 , while the curved-surface mirror  341  may disperse the image coming from the light-path module  31 , such that the image after being dispersed may be processed by a photoelectric conversion in the photoelectric conversion device  32 . By changing the positions of the curved-surface mirrors  332 ,  341  in the light-path route, the flexible design to adjust the entire light-path route may be matched. Especially, the length of the entire light-path route may be shortened. Furthermore, the volumes of the light-path device and the entire optical scanner may all be reduced, the cost is saved relatively, and the effectiveness of the optical reflection is benefited extremely. The light-path route summarized from FIG. 3 through FIG. 7 is described sequentially as the following: light-source device (light source  30 )=&gt;object  10 =&gt;curved-surface mirror (curved-surface mirror  332 )=&gt;reflection device (reflection mirrors  311 ,  312 ,  313 )=&gt;light-focusing device (lens  314 )=&gt;curved-surface mirror (curved-surface mirror  341 )=&gt;photoelectric conversion device  32  (CCD).  
         [0032]    Applied in the invention, the curved-surface mirror positioned in and inter-related with the light-path device appropriately may reach the adjustment and the design of a magnification ratio. By arranging the curved-surface between the scanned document and the light-path module, it may magnify the scanned image and further shorten the size between the scanned object and the light-path module. Through the curved-surface mirror designed between the light-path module and the photoelectric conversion device, it may shrink the scanned image and further shorten the size between the light-path module and the photoelectric conversion device. This intricate conception not only breaks through the impossibly resolved problem of the prior arts, but also provides an enhancement of new effectiveness.