Patent Publication Number: US-9404625-B2

Title: Optical touch device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation of U.S. patent application Ser. No. 14/056,951, filed on Oct. 18, 2013, titled Optical Touch Module and Device Thereof, listing Cheng-Nan Lien, Jinhua Tan, Zijun Meng and Chih-Wei Chang as inventors. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to a touch module and a device thereof, and more particularly to an optical touch module and a device thereof. 
     2. Description of the Related Art 
     Due to the promotion of the quality of LED and the advance of the manufacturing process, optical touch module has the advantages of high transparency, sensitivity to touch of any material and applicability to large-size device. Accordingly, optical touch module is currently widely applied to various displays. The principle of the optical touch display is to employ LED transmitters and LED receivers arranged on opposite sides of the surface of the display. The infrared LEDs around the surface of the display screen form a dense infrared network in X axis and Y axis on the surface. When a nontransparent object interrupts the infrared ray, the X-axis and Y-axis coordinates are naturally found. The infrared LEDs are independent from each other. The location can be achieved simply by means of analyzing the interruption position. Finally, a control circuit calculates and transmits the signal to a PC to show the touch position on the screen. Alternatively, other programs will execute other signal operation and application. The infrared touch panel is triggered by means of interrupting the LED infrared signal so that the signal can be triggered without touching the substrate. Therefore, the infrared touch panel has the advantage of high sensitivity. 
       FIG. 1A  is a top view of a conventional infrared touch device  10 . The infrared touch device  10  includes a frame body composed of four infrared touch modules  11 . Two sets of corresponding LED transmitters  12  and LED receivers  13  are respectively disposed on two opposite sides of the frame body. The LED transmitters  12  are respectively aimed at the LED receivers  13 . 
       FIG. 1B  is a sectional view taken along line X-X of  FIG. 1A , which shows the cross section of one side of the infrared touch device  10  for illustrating the composition of one infrared touch module  11  (as shown in  FIG. 1A ). The LED transmitter is taken as an example in the drawing. However, the LED receiver has the same composition. The infrared touch circuit module includes a control circuit board  111  on which an LED circuit board  112  is disposed. The LED transmitter  12  is disposed on the LED circuit board  112 . Control IC is disposed on the control circuit board  111  for controlling the LED transmitter  12  of the LED circuit board  112 . The control circuit board  111  and the LED circuit board  112  are connected with each other by means of soldering. Accordingly, multiple first soldering points  15  of solder material are formed between the opposite faces of the control circuit board  111  and the LED circuit board  112  in predetermined positions. The control circuit board  111  and the LED circuit board  112  are connected through the first soldering points  15 , whereby the signals of the two circuit boards are transmitted through the first soldering points  15 . In general, in consideration of the signal transmission between the two circuit boards, there is more than one first soldering point  15 . Generally, the solder material is formed of those metal materials with lower melting point, such as tin. 
     Please refer to  FIG. 1C , which is a perspective view of the conventional infrared touch device composed of four infrared touch modules  11  connected with each other to form the frame body. Four L-shaped connection boards  16  are used as four corners of the frame body. Each L-shaped connection board  16  is connected between two infrared touch modules  11  of two sides of the frame body. That is, each infrared touch module  11  is connected between two L-shaped connection boards  16 . The four infrared touch modules  11  are connected with each other via the four L-shaped connection boards  16  to form the frame body. 
     Please now refer to  FIG. 1D , which is a sectional view taken along line Y-Y of  FIG. 1C . The four L-shaped connection boards  16  are disposed under the control circuit board  111  and connected therewith by means of soldering. Multiple second soldering points  17  of solder material are formed between the control circuit board  111  and the L-shaped connection boards  16  in predetermined positions. By means of the second soldering points  17 , the four infrared touch modules  11  are connected with each other for signal transmission therebetween. 
     According to the above, each L-shaped connection board  16  is connected between the control circuit boards  111  of two infrared touch modules  11  of two sides of the frame body. In general, there are more than one first soldering point  15  and more than one second soldering point  17 . Therefore, it takes long time to complete the soldering operation and it is hard to control the quality. Moreover, it is impossible to arrange any component on the opposite faces of the control circuit board  111  and the LED circuit board  112 , that is, the overlapping sections of the two circuit boards. As a result, the infrared touch device  10  has a large invalid area. This is unbeneficial to circuit design and it is hard to rework or service the device. 
     SUMMARY OF THE INVENTION 
     It is therefore a primary object of the present invention to provide an optical touch module and a device thereof. In the optical touch module, the LED circuit board and the control circuit board are connected with each other by means of connectors for signal transmission between the two circuit boards. The connectors can be repeatedly plugged and unplugged so that it is convenient to locate and assemble the optical touch modules without any soldering process. In this case, the malfunction due to improper soldering operation can be avoided. Moreover, the optical touch module is easy to rework and service and reassemble into the original state. 
     It is a further object of the present invention to provide the above optical touch module and the device thereof. In the optical touch module, the LED circuit board and the control circuit board are connected with each other by means of connectors, whereby a height gap exists between the opposite faces of the LED circuit board and the control circuit board. This increases usable space so that electronic components with a height smaller than that of the connectors can be arranged on the opposite faces of the LED circuit board and the control circuit board. Also, an extension section of a filter member can extend into the space to increase the connection strength as a whole. 
     To achieve the above and other objects, the optical touch module of the present invention includes: an LED circuit board having a first top face and a first bottom face, multiple LED components being disposed on the first top face, the first bottom face having at least one first connector; and a control circuit board positioned under the LED circuit board, the control circuit board having a second top face and a second bottom face, the second top face facing the first bottom face of the LED circuit board and having at least one second connector correspondingly in adaptation to the first connector, the second bottom face having at least one third connector, the first and second connectors being vertically mated with each other so as to connect the control circuit board under the LED circuit board, a height gap existing between the LED circuit board and the control circuit board, whereby a space is positioned between correspondingly overlapping sections of the first bottom face of the LED circuit board and the second top face of the control circuit board, the first and second connectors being positioned in the space. 
     The optical touch device of the present invention includes: multiple optical touch modules and multiple L-shaped connection boards, which are assembled to form a frame body, each optical touch module including: an LED circuit board having a first top face and a first bottom face, multiple LED components being disposed on the first top face, the first bottom face having multiple first connectors; and a control circuit board positioned under the LED circuit board, the control circuit board having a second top face and a second bottom face, the second top face facing the first bottom face of the LED circuit board and having at least one second connector correspondingly in adaptation to the first connectors, the second bottom face having at least one third connector, each L-shaped connection board having a third top face facing the second bottom face of the control circuit board, the third top face of the L-shaped connection board having at least one fourth connector correspondingly in adaptation to the third connector, the L-shaped connection board being positioned under two adjacent control circuit boards, the first and second connectors being vertically mated with each other and the third and fourth connectors being also vertically mated with each other, whereby the control circuit board is connected under the LED circuit board and the L-shaped connection board is connected under the control circuit board, a height gap existing between the LED circuit board and the control circuit board, whereby a space is positioned between correspondingly overlapping sections of the first bottom face of the LED circuit board and the second top face of the control circuit board, the first and second connectors being positioned in the space. 
     Alternatively, the optical touch device of the present invention includes: multiple optical touch modules each including: an LED circuit board having a first top face and a first bottom face, multiple LED components being disposed on the first top face, the first bottom face having multiple first connectors; and a control circuit board positioned under the LED circuit board, the control circuit board having a second top face and a second bottom face, the second top face facing the first bottom face of the LED circuit board and having at least one second connector correspondingly in adaptation to the first connectors, the second bottom face having at least one third connector; multiple L-shaped connection boards each having a third top face facing the second bottom face of the control circuit board, the third top face of the L-shaped connection board having at least one fourth connector correspondingly in adaptation to the third connector, the L-shaped connection board being positioned under two adjacent control circuit boards, the first and second connectors being vertically mated with each other and the third and fourth connectors being also vertically mated with each other, whereby the control circuit board is connected under the LED circuit board and the L-shaped connection board is connected under the control circuit board, a height gap existing between the LED circuit board and the control circuit board, whereby a space is positioned between correspondingly overlapping sections of the first bottom face of the LED circuit board and the second top face of the control circuit board, the first and second connectors being positioned in the space; and multiple filter members respectively connected with the optical touch modules, each filter member including: a main body; an upper protrusion section extending from an upper end of the main body to one side thereof; and an extension section extending from a lower end of the main body to one side thereof, the upper protrusion section extending to upper sides of the LED components, the main body being positioned in front of the LED components to shield the LED components, the extension section extending into the space between the first bottom face of the LED circuit board and the second top face of the control circuit board. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein: 
         FIG. 1A  is a top view of a conventional infrared touch device; 
         FIG. 1B  is a sectional view taken along line X-X of  FIG. 1A ; 
         FIG. 1C  is a perspective view of the conventional infrared touch device composed of four infrared touch modules connected with each other to form a frame body; 
         FIG. 1D  is a sectional view taken along line Y-Y of  FIG. 1C ; 
         FIG. 2  is an exploded view of the optical touch module of the present invention; 
         FIG. 3A  is an assembled view of the optical touch module of the present invention; 
         FIG. 3B  is a view of a part of the optical touch module of the present invention; 
         FIG. 4  is a perspective exploded view of the optical touch device of the present invention; 
         FIG. 5A  is an exploded view of the optical touch device of the present invention; 
         FIG. 5B  is an assembled view of the optical touch device of the present invention; 
         FIG. 6A  is a sectional view of the optical touch device of the present invention, which has a filter member; 
         FIG. 6B  is a top view of the optical touch device of the present invention, which has a filter member; and 
         FIG. 6C  is a perspective view of the filter member. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Please refer to  FIGS. 2 and 3A .  FIG. 2  is an exploded view of the optical touch module of the present invention.  FIG. 3A  is an assembled view of the optical touch module of the present invention. The optical touch module  20  of the present invention includes an LED circuit board  21  and a control circuit board  22 . The LED circuit board  21  has a first top face  211  and a first bottom face  212 . Multiple LED components  213  are disposed on the first top face  211 . The first bottom face  212  has at least one first connector  214 . The control circuit board  22  is positioned under the LED circuit board  21 . The control circuit board  22  has a second top face  221  and a second bottom face  222 . The second top face  221  faces the first bottom face  212  of the LED circuit board  21  and has at least one second connector  224  for correspondingly plug-connecting with the first connector  214 . The second bottom face  222  has at least one third connector  225  positioned near two ends. 
     The first connector  214  is a male connector, while the second connector  224  is a female connector in adaptation to the first connector  241 . Alternatively, the first connector  214  is female connector, while the second connector  224  is a male connector in adaptation to the first connector  241 . The first and second connectors  214 ,  224  can be correspondingly plug-connected with each other or disconnected from each other so that the connectors can be flexibly replaced. The connector means a medium for connecting two or more objects, such as a socket, a terminal or wiring harness. The connector generally means the connection component and the accessory thereof applied to electronic signal transmission and power supply as a bridge between the interrupted or isolated circuits for passing of current and making the circuits function. 
     The first and second connectors  214 ,  224  are vertically mated with each other so as to connect the control circuit board  22  under the LED circuit board  21 . A height gap p exists between the LED circuit board  21  and the control circuit board  22 , whereby a space  23  is positioned between the correspondingly overlapping sections of the first bottom face  212  of the LED circuit board  21  and the second top face  221  of the control circuit board  22 . The first and second connectors  214 ,  224  are positioned in the space  23 . The height gap p is defined by the total thickness of the first and second connectors  214 ,  224  mated with each other. 
     Please now refer to  FIG. 3B , which is a view of a part of the touch module. The space  23  exists between the overlapping sections of the first bottom face  212  of the LED circuit board  21  and the second top face  221  of the control circuit board  22 . Under such circumstance, at least one electronic component can be arranged in the space  23 . The electronic component has a height smaller than the height of the first connector  214  or the second connector  224 . In the drawing, an electronic component  261  is disposed under the first bottom face  212  of the LED circuit board  21  in a position avoiding the first connector  214 . In addition, an electronic component  262  is disposed on the second top face  221  of the control circuit board  22  in a position avoiding the second connector  224 . The two electronic components  261 ,  262  are positioned in the space  23 . 
     Please now refer to  FIG. 4 , which is a perspective exploded view of the optical touch device of the present invention. Four optical touch modules  20  are connected with each other by means of four L-shaped connection boards  30  to form the optical touch device in the form of a frame body. The four L-shaped connection boards  30  serve as four corners of the frame body. Each L-shaped connection board  30  is connected between two optical touch modules  20  of two sides of the frame body. That is, two ends of each optical touch module  20  are respectively connected with two L-shaped connection boards  30 . The two sets of LED components  213  of the optical touch modules  20  on two opposite sides of the frame body correspond to each other. The LED components  213  on one side are infrared transmitters, while the LED components  213  on the opposite side are infrared receivers. 
     Please now refer to  FIGS. 5A and 5B .  FIG. 5A  is an exploded view of the optical touch device of the present invention.  FIG. 5B  is an assembled view of the optical touch device of the present invention. The L-shaped connection boards  30  are respectively disposed on outer sides of two ends of the control circuit board  22  of each optical touch module  20 . In the drawings, only the L-shaped connection board  30  at one end is shown. The L-shaped connection board  30  has a third top face  31  on which at least one fourth connector  32  is disposed. 
     The first bottom face  212  of the LED circuit board  21  of the optical touch module  20  faces the second top face  221  of the lower control circuit board  22 . The first connector  214  is vertically mated with the second connector  224 , whereby the control circuit board  22  is connected under the LED circuit board  21 . The second bottom face  222  of the control circuit board  22  faces the third top face  31  of the L-shaped connection board  30 . The third connector  225  is vertically mated with the fourth connector  32 , whereby the L-shaped connection board  30  is connected under the control circuit board  22 . Accordingly, the four corners of the optical touch device are three-layer structures in which three layers are piled up and spaced from each other. The uppermost layer is the LED circuit board  21 , the middle layer is the control circuit board  22 , while the lowermost layer is the L-shaped connection board  30 . 
     The height gap p not only exists between the LED circuit board  21  and the control circuit board  22 , but also exists between the control circuit board  22  and the L-shaped connection board  30 . The space  23  is positioned between the correspondingly overlapping sections of the first bottom face  212  of the LED circuit board  21  and the second top face  221  of the control circuit board  22 . In addition, a space  36  exists between the overlapping sections of the second bottom face  222  of the control circuit board  22  and the third top face  31  of the L-shaped connection board  30 . The first and second connectors  214 ,  224  are positioned in the space  23 , while the third and fourth connectors  225 ,  32  are positioned in the space  36 . 
     The electronic component  261  disposed under the first bottom face  212  of the LED circuit board  21  and the electronic component  262  disposed on the second top face  221  of the control circuit board  22  are positioned in the space  23 . 
     Please refer to  FIGS. 6A, 6B and 6C .  FIG. 6A  is a sectional view of the optical touch device of the present invention, which has a filter member.  FIG. 6A  is a top view of the optical touch device of the present invention, which has a filter member.  FIG. 6C  is a perspective view of the filter member. The optical touch device of the present invention further includes a filter member  40  disposed in front of each optical touch module  20  to shield the LED components  213  from the interference of the environmental light. The filter member  40  such as an infrared filter member is made of a plastic material to which a dye is added. The infrared filters are generally classified into two types. The first type is high-pass filter, which is transparent to the light with a wavelength larger than 850 nm or 940 nm. The second type is low-pass filter, which is transparent to the light with a wavelength within a range from 925 nm to 955 nm. The above filter member is only an example and not intended to limit the material or form of the filter member of the present invention. Other suitable filter members are also applicable to the present invention. 
     The filter member  40  includes a main body  41 , an upper protrusion section  42  extending from an upper end of the main body  41  to one side thereof and an extension section  43  extending from a lower end of the main body  41  to one side thereof. The upper protrusion section  42  extends to upper sides of the LED components  213 . The main body  41  is positioned in front of the LED components  213  to shield the same. The extension section  43  extends into the space  23  between the first bottom face  212  of the LED circuit board  21  and the second top face  221  of the control circuit board  22 . 
     The extension section  43  is formed with recesses  44  in positions of the first and second connectors  214 ,  224  and the electronic components  261 ,  262  in the space  23 . Therefore, the extension section  43  can extend into the space  23  without interfering with the first and second connectors  214 ,  224  or the electronic components  261 ,  262 . An adhesive layer  45  is disposed between a lower surface of the extension section  43  and the control circuit board  22 . The adhesive layer  45  has adhesion on both faces, whereby the extension section  43  is adhered to the control circuit board  22 . The adhesive layer  45  is such as a double-faced adhesive tape or the like. 
     In conclusion, four optical touch modules  20  are connected with each other by means of four L-shaped connection boards  30  to form the optical touch device of the present invention in the form of a frame body. By means of the first and second connectors  214 ,  224  and the third and fourth connectors  225 ,  32 , the LED circuit boards  21  and the control circuit boards  22  of the optical touch modules  20  are connected with each other and the four optical touch modules  20  and the L-shaped connection boards  30  are connected with each other. Accordingly, not only the signals can be transmitted between the two circuit boards, but also the signals can be transmitted between the optical touch modules  20 . The first and second connectors  214 ,  224  and the third and fourth connectors  225 ,  32  can be repeatedly plugged and unplugged. Therefore, it is convenient to locate and assemble the optical touch modules  20  without any soldering process. In this case, the malfunction due to improper soldering operation can be avoided. Moreover, the optical touch modules are easy to rework and service and reassemble into the original state. A height gap p exists between the opposite faces of the LED circuit board  21  and the control circuit board  22 . This increases usable space so that electronic components with a height smaller than that of the first and second connectors  214 ,  224  can be arranged on the opposite faces of the LED circuit board  21  and the control circuit board  22 . Also, the extension section  43  of the filter member  40  can be positioned in the space to increase the connection strength as a whole. 
     The present invention has been described with the above embodiments thereof and it is understood that many changes and modifications in the above embodiments can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims.