Abstract:
An imaging system switching device is described. The imaging system switching device is used for multi-function office machines, which has a scanner and a printer and additionally a copy machine and a fax machine. The imaging system switching device has a roller, a lens, a reflector, an optical receiver, an optical transmitter, and an optical switch. The optical switch changes light streams transmitting route for different function so as to use the same transmitting elements for a scan function and a print function. Another aspect of the imaging system switching device further has an original roller so that the switching device of the imaging system can simultaneously scan and print.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to a switching device, and especially, to an optical switching device for an image system.  
         BACKGROUND OF THE INVENTION  
         [0002]    Due to the rapid progress of the optical and semiconductor technology, office machines, such as fax machines, copy machines, scanners, and printers, not only be reduced in size but also be increased in accuracy.  
           [0003]    A laser printer is popular for printing original documents. A working theory of the laser printer is to uniformly spread electrostatic charge on a photo conductor drum and then expose the photo conductor drum to light streams to form a electrostatic latent image thereon. Subsequently, toners are attached on the photo conductor drum by way of an electric field action to reproduce a toner image and then the toner image is transferred to a paper.  
           [0004]    A scanner is utilized to read documents, including texts and/or pictures. The scanner utilizes a light source to expose the documents under light streams and through a lens to accumulate reflected light streams on a charge coupled device (CCD) or contact image sensor (CIS) for transferring optical signals into electrical signals. The electrical signals are then transferred into digital signals with an analog/digital converter and finally these digital image data are stored to complete the scanning procedure.  
           [0005]    A fax machine reads an image, such as texts and/or pictures, and sends the same to a remote fax machine to reproduce the image there. In addition, a copy machine reads an image and reproduces the image therein immediately. Because the above office machines include some overlapping functions, a multi-function office machine is designed to combine the above functions of the office machines into one machine. A popular multi-function office machine includes functions of a printer, a scanner, a copy machine, and fax machine.  
           [0006]    For a current multi-function office machine, a flatbed scanner or a sheetfed scanner is normally utilized to read the image and a printer is utilized to output the image. Therefore, the multi-function office machine includes scanning and printing functions, and may further include copy and fax functions. The multi-function office machine combines multiple conventional office machines into one machine so as to reduce space requirements in an office. However, a conventional multi-function office machine still occupies a quite large area of an office desk.  
         SUMMARY OF THE INVENTION  
         [0007]    One object of the present invention is to provide a switching device for an imaging system to integrate efficiently together optical transmitting devices of a multi-function office machine.  
           [0008]    Another object of the present invention is to provide a switching device for an imaging system to reduce efficiently the size of a multi-function office machine.  
           [0009]    Yet another object of the present invention is to provide a switching device for an imaging system to reduce efficiently the total cost of a multi-function office machine.  
           [0010]    To achieve these and other advantages and in accordance with the object of the invention, the present invention provides an imaging system switching device utilized in a multi-function office machine. The imaging system switching device provides scan, print, copy, and fax functions. The imaging system switching device has a roller, a reflector, lens, an optical receiver, an optical transmitter, and an optical switch. The reflector swings in a predetermined angle and cooperates with the roller rotation to scan and/or print contents of a document. The optical receiver receives optical scanning signals and transfers the same to digital signals while the imaging system switching device is scanning an input document. The optical transmitter generates optical output signals while the imaging system switching device is printing an output document. The optical switch is capable of switching optical signal transmitting paths.  
           [0011]    When the imaging system switching device is scanning the input document, the roller rotates the input document and cooperates with the reflector to scan the whole input document. The optical receiver receives optical scanning signals and then transforms the same into digital signals for storage. In addition, an optical switch is disposed between the reflector and the optical receiver to receive light streams generated by an optical transmitter to light up the input document. The light stream path between the optical switch and the roller is the same for the light streams generated by the optical transmitter and the light streams received by the optical receiver so that the lighting position and the scanning position are the same position. Hence, the lighting efficiency thereof is increased. The optical transmitter is a semiconductor light source, such as a light emitting diode or a laser diode.  
           [0012]    When the imaging system switching device prints an output document, the optical transmitter generates optical output signals to the optical switch, and the optical switch transmits the optical output signals to the reflector by way of the lens. The reflector swings and cooperates with the rotation of the roller to form an electrostatic latent image thereon, and the electrostatic latent image with toner is then transferred onto an output medium.  
           [0013]    When the imaging system switching device executes a copy procedure, the imaging system switching device scans the input document and then prints the input document. When the imaging system switching device executes a fax procedure, the imaging system switching device scans the input document and utilizes a telephone device to transmit the input document to a remote fax machine.  
           [0014]    The optical transmitter is a light emitting diode (LED) or a laser diode. The optical receiver comprises a photo diode. The optical switch is a mechanical optical switch, a Micro Electro Mechanical System (MEMS) optical switch or a beam splitter.  
           [0015]    Another aspect of the present invention is to provide an imaging system switching device in which an additional roller is provided and the optical switch is the preferred optical path routing device. Therefore, the imaging system switching device according to the present invention can simultaneously execute scanning and print functions to enhance the speed of the copy function. The optical path routing device can simultaneously transmit the optical output signals and the optical scanning signals without interference. The optical path routing device is a beam splitter, a total internal reflection (TIR) prism, or an optical router.  
           [0016]    Therefore, the imaging system switching device according to the present invention efficiently reduces the volume of the multi-function office machine and therefore the occupation area of the office desk is also reduced. The manufacture cost is also reduced because the optical transmission components for scanning and printing are the same. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]    The foregoing aspects and many of the attendant advantages of this invention will be more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:  
         [0018]    [0018]FIG. 1A is a schematic top view of a first preferred embodiment of the imaging system switching device according to the present invention;  
         [0019]    [0019]FIG. 1B is a schematic side view of the first preferred embodiment of FIG. 1A;  
         [0020]    [0020]FIG. 2A is a schematic top view of a second preferred embodiment of the imaging system switching device according to the present invention; and  
         [0021]    [0021]FIG. 2B is a schematic side view of the second preferred embodiment of FIG. 2A. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0022]    The following description is the best presently contemplated mode of carrying out the present invention. This description is not to be taken in a limiting sense but is made merely for the purpose of describing the general principles of the invention. The scope of the invention should be determined by referencing the appended claims.  
         [0023]    Referred to FIG. 1A and FIG. 1B, FIG. 1A is a schematic top view of a first preferred embodiment of the imaging system switching device according to the present invention, and FIG. 1B is a schematic side view thereof. The imaging system switching device  200  includes a roller  210 , lens  220 , a reflector  230 , an optical switch  270 , an optical transmitter  290 , and an optical receiver  300 . The switching device  200  combines the optical transmitting system and the optical receiving system together so that a main optical transmission path of a scanner and a main optical transmission path of a printer machine are combined into a same structure. Therefore, a size of the multi-function office machine is reduced so as to be more suitable for use on an office desk.  
         [0024]    In a scanning procedure, the switching device  200  scans a document on the roller  210  to receive optical signals from a path of light streams  240  to a path of light stream  245 , that is, a scanning range  250 ; meanwhile, the roller  210  provides another direction of movement, rotation, of the document. Therefore, the switching device  200  utilizes a reflector  230  to scan among a swing angle  280  for constructing a scanning range  250  and cooperates with the roller  210  completely to scan the whole page of the document.  
         [0025]    Meanwhile, the optical signals scanned from the path of light streams  240  to the path of light streams  245  are transmitted to the reflector  230  by way of the lens  220 , and the same are reflected to the optical switch  270  by way of the lens  220  through a path of light streams  260 . Subsequently, the optical switch  270  switches the optical signals to the optical receiver  300 . The optical receiver  300  then transforms the optical signals into digital data for storage.  
         [0026]    Normally, in a scanning procedure, a conventional scanner utilizes a fluorescent tube to light up the document. The imaging system switching device  200  according to the present invention can utilize the optical transmitter  290  to light up the document for scanning. Because the optical receiver  300  and the optical transmitter  290  utilizes a same transmission path to transmit respective light streams between the optical switch  270  and the document disposed on the roller  210 , the optical transmitter  290  lights up a position where the optical receiver  300  is scanning so that the lighting efficiency and accuracy are efficiently enhanced. The optical transmitter  290  may use any point light source to light up the document, for example a light emitting diode (LED) or a laser diode.  
         [0027]    In a printing procedure, the switching device  200  utilizes the optical transmitter  290  to transmit optical signals to the optical switch  270 . The optical switch  270  can switch the transmission path according to a predetermined work requirement of the switching device  200 . These optical signals construct the light streams  260  and transmit to the reflector  230  by way of the lens  220 . The reflector  230  then swings in the swing angle  280  to reflect the light streams  260  to the roller  210  by way of the lens  220 . Moreover, the swing angle  280  of the reflector  230  can reflect the optical signals between the paths of light streams  240  and light streams  245 . The roller  210  further provides another direction of movement, rotation, to form an electrostatic latent image thereon by the optical signals transmitted by the optical transmitter  290 . Subsequently, the electrostatic latent image on the roller  210  is toners attached by way of an electric field action to reproduce a toner image thereon. Finally, the toner image is transferred from the roller  210  onto a medium, such as paper.  
         [0028]    In this preferred embodiment, the roller  210  is preferably a photo conductive drum to achieve both a document printing function and a document feeding function. The present invention combines the optical components of a scanner and the optical components of a printer together so that the size of the multi-function office machine can be efficiently reduced. Accordingly, the occupation area on an office desk is also efficiently reduced. Further, the same lens or a different lens can be selected as the lens  220  for receiving and transmitting optical signals. In addition, the optical switch  270  is utilized to switch the optical signals to different output devices according to the predetermined purpose thereof. Therefore, the optical switch  270  can be a mechanical optical switch, that is, a step motor to move an optical fiber, a mirror, a prism, or any other element to change the light stream path. A Micro Electro Mechanical System (MEMS) optical switch can also be selected for the optical switch  270 , which utilizes a silicon semiconductor to form a micro electro mechanical structure. The optical switch  270  can further use a beam splitter or a total internal reflection (TIR) prism to separate the receiving optical signals and the transmitting optical signals.  
         [0029]    Referring to FIG. 2A and FIG. 2B, FIG. 2A is a schematic top view of a second preferred embodiment of the imaging system switching device according to the present invention, and FIG. 2B is a schematic side view thereof. The imaging system switching device  500  includes two rollers  310  and  400 , lens  320 , a reflector  330 , an optical path routing device  370 , an optical transmitter  390 , and an optical receiver  430 . The roller  310  is a photo conductive drum and the roller  400  is a roller for feeding papers.  
         [0030]    The switching device  500  of the second preferred embodiment can further achieve scanning and printing functions simultaneously. As a document is being scanned on the roller  400 , optical signals construct light streams  410  and transmit to the reflector  330  by way of the lens  320 . The reflector  330  swings between a swing angle  380  to execute a scanning procedure. In additional, the roller  400  provides another direction of movement, rotation, so as to scan texts and/or pictures on the whole document.  
         [0031]    The light streams  410  therefore are reflected by the reflector  330  and transmitted to the optical path routing device  370  by way of the lens  320 . Accordingly, the optical signals are furthermore transmitted to the optical receiver  430  along the path of light streams  420 , and therefore the digital data of the scanned image are generated and stored.  
         [0032]    Furthermore, when the image printing function and the scanning function are executed simultaneously, the optical transmitter  390  generates optical signals to construct light stream  360 . The light streams  360  are transmitted to the optical path routing device  370  and then to lens  320  via a predetermined path. Subsequently, the light streams  360  are transmitted to the roller  310 , a photo conductive drum, along the path of light streams  340  by way of the lens  320 . The optical signals generated by the optical transmitter  390  are transformed into an electrostatic latent image on the roller  310  while the reflector  330  swings between the path of light streams  340  and the path of light streams  345  with the swing angle  380  to form a scanning range  350  and combine with the rotation of the roller  310 . Subsequently, toners are attached to the electrostatic latent image on the roller  310  by way of electric field action to reproduce a toner image thereon. Finally, the toner image is transferred from the roller  310  to paper.  
         [0033]    In the second preferred embodiment, the roller for scanning images and the roller for printing images are different. The other optical transmission components are combined together. Therefore, the switching device  500  can simultaneously scan and print an image. The transmission signals and reception signals can simultaneously exist in the same optical transmission components by way of different transmitting paths. Therefore, a multi-function office machine with the imaging system switching device according to the present invention can scan and print at the same time.  
         [0034]    Furthermore, the same or different lenses can be chosen as the lens  320  for receiving and transmitting optical signals. In addition, the optical path routing device  370  separates the light streams from different sources and transmits them to the respective objective components. Therefore, the optical path routing device  370  can be a beam splitter, a total internal reflection prism, or an optical router to separate the received optical signals and the transmitted optical signals into respective transmission paths without interference. A copy function combines the scanning function and the printing function. Therefore, a multi-function office with the second preferred embodiment according to the present invention has an efficiently enhanced copy speed. In additional, when the switching device according to the present invention is integrated with a telephone device, the scanned image can be immediately transmitted to a remote fax machine.  
         [0035]    The switching device  500  can further combine the optical transmitter  290  and the optical receiver  300  according to the first preferred embodiment of FIGS. 1A and 1B to light up a same position with the same transmission path by way of the optical switch  270  for lighting and scanning the document to enhance the lighting efficiency and accuracy. As is understood by a person skilled in the art, the foregoing preferred embodiments of the present invention are illustrative of the present invention rather than limiting of the present invention.  
         [0036]    It is intended that various modifications and similar arrangements be included within the spirit and scope of the appended claims, the scope of which should be accorded the broadest interpretation so as to encompass all such modifications and similar structures.