Abstract:
Scanning methods with light mixing are provided. A scanning method with light mixing includes the steps of providing a scan target and a scanner, wherein the scanner comprises three light sources of different colors, disposing the scan target on the scanner, selecting two light sources from the three light sources, turning on the two selected light sources simultaneously to form a mixed light source, illuminating the scan target by the mixed light source, and scanning the scan target to generate an image signal.

Description:
BACKGROUND  
       [0001]     The invention relates to scanning methods with light mixing.  
         [0002]     Conventionally, in a scanner with contact image sensor (CIS), a scan target is illuminated by three light sources of red (R), green (G), and blue (B) respectively and then scanned by a contact image sensor (CIS) to generate a scan image having RGB color information.  
         [0003]     When the scan target, such as a document, needs to be printed, the scan image must be transformed from RBG format to CMY format (cyan (C), magenta (M), and yellow (Y)), to be compatible with printer specification, thus potentially causing loss of color information and waste of time.  
       SUMMARY  
       [0004]     Scanning methods with light mixing are provided.  
         [0005]     An embodiment of a scanning method with light mixing includes the steps of providing a scan target and a scanner comprising three light sources of different colors, disposing the scan target on the scanner, selecting two from the three light sources, turning on the two selected light sources simultaneously to form a mixed light source, illuminating the scan target by the mixed light source, and scanning the scan target to generate an image signal.  
         [0006]     Some embodiments of a scanning method with light mixing include the steps of providing a scan target and a scanner comprising a first, a second, and a third light sources of different colors, disposing the scan target on the scanner, turning on the first and second light sources simultaneously to form a first mixed light source, and illuminating the scan target by the first mixed light source and scanning the scan target to generate a first image signal.  
         [0007]     Some embodiments of a scanning method with light mixing include the steps of providing a scan target and a scanner comprising three light sources of different colors, disposing the scan target on the scanner, determining an output mode of the scanner, and if the output mode is “PREVIEW”, turning on the three light sources to illuminate the scan target sequentially and scanning the scan target to generate a first scan image, and if the output mode is “PRINT”, turning on two of the three light sources sequentially to form three mixed light sources, illuminating the scan target by the three mixed light sources sequentially, and scanning the scan target to generate a second scan image. 
     
    
     DESCRIPTION OF THE DRAWINGS  
       [0008]     The invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:  
         [0009]      FIG. 1  is a schematic diagram of an embodiment of a scanner;  
         [0010]      FIG. 2  is a flowchart of an embodiment of a scanning method with light mixing;  
         [0011]      FIG. 3  is a schematic diagram of another embodiment of a scanner, wherein the scanner is connected to a printer in a computer system;  
         [0012]      FIG. 4  is a flowchart of another embodiment of a scanning method with light mixing;  
         [0013]      FIG. 5  is a schematic diagram of another embodiment of a scanner, wherein the scanner is connected to a printer and a display in a computer system; and  
         [0014]      FIG. 6  is a flowchart of another embodiment of a scanning method with light mixing. 
     
    
     DETAILED DESCRIPTION  
       [0015]     The invention provides a method of generating a scan image having CMY color information, in addition to a scan image having RGBcolor information, by forming three mixed light sources by turning on two of the three light sources sequentially and illuminating a scan target by the three mixed light sources sequentially. To preview the scan target, the scanner outputs the scan image having RGB color information. To print the scan target, the scanner outputs the scan image having CMY color information.  
         [0016]      FIG. 1  is a schematic diagram of an embodiment of a scanner  101 .  
         [0017]     The scanner  101  includes three light sources  102  of different colors and an image capture unit  103 .  
         [0018]     The three light sources  102  are a red light source  102   a , a green light source  102   b , and a blue light source  102   c  respectively.  
         [0019]     The image capture unit  103  is a contact image sensor (CIS), scanning a scan target disposed on the scanner  101 .  
         [0020]      FIG. 2  is a flowchart of an embodiment of a scanning method with light mixing.  
         [0021]     First, in step S 11 , the scan target is disposed on the scanner  101 .  
         [0022]     In step S 12 , two light sources are selected from the three light sources  102  according to requirements. In this embodiment, the red light source  102   a  and the green light source  102   b  are selected.  
         [0023]     In step S 13 , the two selected light sources are turned on simultaneously to form a mixed light source. In this embodiment, the mixed light source formed by turning on the red light source  102   a  and the green light source  102   b  simultaneously is a yellow light source. Additionally, in this step, the scan target is illuminated by the mixed light source.  
         [0024]     Finally, in step S 14 , the image capture unit  103  scans the scan target to generate an image signal.  
         [0025]     In this embodiment, the image signal generated is an image signal from which yellow color is filtered out.  
         [0026]      FIG. 3  is a schematic diagram of another embodiment of a scanner  201 , wherein the scanner  201  is connected to a printer  204  in a computer system.  
         [0027]     The scanner  201  includes three light sources  202  of different colors and an image capture unit  103 . The scanner  201  is connected to the printer  204  in the computer system.  
         [0028]     The three light sources  202  are a first light source  202   a , a second light source  202   b , and a third light source  202   c  respectively. In this embodiment, the first light source  202   a  is red, the second light source  202   b  is green, and the third light source  202   c  is blue.  
         [0029]     The image capture unit  203  is a contact image sensor (CIS), scanning a scan target disposed on the scanner  201 .  
         [0030]      FIG. 4  is a flowchart of another embodiment of a scanning method with light mixing.  
         [0031]     First, in step S 21 , the scan target is disposed on the scanner  201 .  
         [0032]     In step S 22 , the first light source  202   a  and the second light source  202   b  are turned on simultaneously to form a first mixed light source. In this embodiment, the first mixed light source formed by turning on the red light source  202   a  and the green light source  202   b  simultaneously is a yellow light source. Additionally, in this step, the scan target is illuminated by the first mixed light source.  
         [0033]     In step S 23 , the image capture unit  203  scans the scan target to generate a first image signal.  
         [0034]     In step S 24 , the second light source  202   b  and the third light source  202   c  are turned on simultaneously to form a second mixed light source. In this embodiment, the second mixed light source formed by turning on the green light source  202   b  and the blue light source  202   c  simultaneously is a cyan light source. Additionally, in this step, the scan target is illuminated by the second mixed light source.  
         [0035]     In step S 25 , the image capture unit  203  scans the scan target to generate a second image signal.  
         [0036]     In step S 26 , the third light source  202   c  and the first light source  202   a  are turned on simultaneously to form a third mixed light source. In this embodiment, the third mixed light source formed by turning on the blue light source  202   c  and the red light source  202   a  simultaneously is a magenta light source. Additionally, in this step, the scan target is illuminated by the third mixed light source.  
         [0037]     In step S 27 , the image capture unit  203  scans the scan target to generate a third image signal.  
         [0038]     In step S 28 , the first, the second, and the third image signals are combined to form a scan image having CMY color information, i.e. cyan, magenta, yellow color information.  
         [0039]     Finally, in step S 29 , the scan image is output to the printer  204  directly.  
         [0040]     It is noted that because the printer  204  can process a CMY image directly, the scan image can be input to the printer  204  directly without any transformation or processing.  
         [0041]      FIG. 5  is a schematic diagram of another embodiment of a scanner  301 , wherein the scanner  301  is connected to a printer  304  and a display  305  in a computer system.  
         [0042]     The scanner  301  includes three light sources  302  of different colors and an image capture unit  303 . The scanner  301  is connected to the printer  304  and the display  305  in the computer system.  
         [0043]     The three light sources  302  are a red light source  302   a , a green light source  302   b , and a blue light source  302   c  respectively.  
         [0044]     The image capture unit  303  is a contact image sensor (CIS), scanning a scan target disposed on the scanner  301 .  
         [0045]      FIG. 6  is a flowchart of another embodiment of a scanning method with light mixing.  
         [0046]     First, in step S 31 , the scan target is disposed on the scanner  301 .  
         [0047]     In conditional step C 31 , an output mode of the scanner  301  is determined.  
         [0048]     If the output mode is “PREVIEW”, the process goes to step S 32 . In step S 32 , the three light sources  302   a ,  302   b ,  302   c  are turned on sequentially to illuminate the scan target.  
         [0049]     Next, in step S 33 , the image capture unit  303  scans the scan target to generate a first scan image.  
         [0050]     Finally, in step S 34 , the first scan image is output to the display  305  after which the process stops.  
         [0051]     If the output mode is “PRINT”, the process goes to step S 35 . In step S 35 , two of the three light sources  302   a ,  302   b ,  302   c  are turned on sequentially to form three mixed light sources. In this embodiment, the three mixed light sources formed are yellow, cyan, and magenta light sources respectively. Additionally, in this step, the scan target is illuminated by the three mixed light sources sequentially.  
         [0052]     Next, in step S 36 , the image capture unit  303  scans the scan target to generate a second scan image.  
         [0053]     Finally, in step S 37 , the second scan image is output to the printer  304  after which the process stops.  
         [0054]     Some embodiments of a scanning method with light mixing can generate a scan image having CMY color information, in addition to a scan image having RGB color information, by forming three mixed light sources by turning on two of the three light sources sequentially and illuminating a scan target by the three mixed light sources sequentially.  
         [0055]     To preview the scan target, the scanner outputs the scan image having RGB color information, and to print the scan target, the scanner outputs the scan image having CMY color information, thus avoiding loss of color information and waste of time due to color format transformation.  
         [0056]     While the invention has been described by way of example and in terms of preferred embodiments, it is to be understood that the invention is not limited thereto. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.