Patent Document

CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the right of priority based on Taiwan Patent Application No. 100135510 entitled “TRANSPARENCY ADJUSTING APPARATUS AND DISPLAY DEVICE HAVING THE SAME”, filed on Sep. 30, 2011, which is incorporated herein with reference and assigned to the assignee herein. 
     FIELD OF THE INVENTION 
     The present invention relates to display devices, and more particularly, to an anti-reflection anti-glare transparency adjusting apparatus and a display device having the same. 
     BACKGROUND OF THE INVENTION 
     Due to the increasing demand for the human-machine interfaces for use with various electronic products, especially the rapid development of numerous handheld touch-controlled devices, the application of display devices is becoming wider. A display device (such as a liquid crystal display device) is typically equipped with a cover glass for functioning as a display window and covering the display device. 
     In this regard, an important research topic is about reduction of mirror reflection that originates from various display device surfaces. It is because, when operating in an environment of a high light intensity (for example, outdoors or in the presence of a strong light source), most electronic products are affected by reflection overwhelmingly, and thus the quality of image display of display devices are compromised. 
     There are plenty of conventional methods of reducing the aforesaid minor reflection. For example, the cover glass of a display device is coated with an anti-reflection film, and its anti-reflection performance is enhanced by adjusting its thickness and refractive index. However, a touch control process performed on the display device entails touching the surface of the anti-reflection film with a finger frequently, and in consequence the anti-reflection film undergoes wear and tear and even peels off to the detriment of its anti-reflection effect. 
     Another conventional method involves coarsening the cover glass surface by an etching process in order to turn the cover glass surface into an anti-glare surface. During the etching process, the cover glass surface is exposed to a specific chemical whereby the cover glass surface is coarsened to a certain extent so as to scatter visible light. However, this method achieves its goal at the cost of reducing the transparency of the cover glass greatly and using a corrosive acidic solution during the etching process to the detriment of environmental protection. 
     SUMMARY OF THE INVENTION 
     In an embodiment of the present invention, a transparency adjusting apparatus comprises: a first transparent shell; a heater disposed on the first transparent shell; and a second transparent shell disposed on the first transparent shell; wherein the first transparent shell and the second transparent shell are sealed to define a sealed space for containing a working fluid therein and the working fluid absorbs heat from the heater and evaporates to condense on the second transparent shell, thereby adjusting the transparency of the second transparent shell. 
     The transparency adjusting apparatus further comprises a transparency detector. The transparency detector comprises a light emitter and a light receiver. The light emitter emits a light beam that passes through the first transparent shell and the second transparent shell before being received by the light receiver, so as to obtain data pertaining to the transparency of the first transparent shell and the second transparent shell. The transparency adjusting apparatus further comprises a control circuit electrically connected to the light emitter, the light receiver, and the heater. The control circuit receives the data pertaining to the transparency of the first transparent shell and the second transparent shell and sends the data to the heater, so as to control the saturation pressure and boiling point of the working fluid. 
     In response to the starting of the heater to heat up the sealed space, the saturation pressure and the boiling point of the working liquid rising to condense vapor of the working liquid, thereby forming a condensed layer and reducing the transparency of the second transparent shell. 
     In another embodiment of the present invention, a display device comprises: a display panel; a first transparent shell disposed in front of the display panel; a heater disposed on the first transparent shell; and a second transparent shell disposed on the first transparent shell; wherein the first transparent shell and the second transparent shell are sealed to define a sealed space for containing a working fluid therein and the working fluid absorbs heat from the heater and evaporates to condense on the second transparent shell, thereby adjusting the transparency of the second transparent shell. 
     In yet another embodiment of the present invention, a transparency adjusting apparatus for a display device or kits thereof, configured as being disposed in front of a display surface of the display device or kits thereof, comprising: a first transparent shell body comprising a first transparent shell portion and a second transparent shell portion; and a heater disposed on the first transparent shell portion; wherein the first transparent shell portion and the second transparent shell portion together define a sealed space for containing a working fluid therein and the working fluid absorbs heat from the heater and evaporates to condense on the second transparent shell portion, thereby adjusting the transparency of the second transparent shell portion. 
     Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present invention should be or are in any single embodiment of the invention. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, discussion of the features and advantages, and similar language, throughout this specification may, but do not necessarily, refer to the same embodiment. 
     Furthermore, the described features, advantages, and characteristics of the invention may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the invention may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order that the advantages of the invention will be readily understood, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings. 
         FIG. 1  is a schematic view of a display device according to a preferred embodiment of the present invention; 
         FIG. 2  is a block diagram of the display device of  FIG. 1 ; 
         FIG. 3  is a cross-sectional view of a display device according to a preferred embodiment of the present invention; 
         FIG. 4  is a cross-sectional view of a display device according to another preferred embodiment of the present invention; 
         FIG. 5  is a schematic view of the operation of a transparency adjusting apparatus for a display device according to another preferred embodiment of the present invention; 
         FIG. 6  is a schematic view of the operation of a transparency adjusting apparatus for a display device according to yet another preferred embodiment of the present invention; and 
         FIG. 7  is a schematic view of a self-contained transparency adjusting apparatus disposed at a display device according to a further preferred embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Referring to  FIG. 1 , there is shown a schematic view of a display device  100  according to a preferred embodiment of the present invention. As shown in  FIG. 1 , the display device  100  comprises a display panel  200 . For example, the display panel  200  is a touch panel. For example, the touch panel is an infrared touch panel. In practice, the touch panel comes in different forms, including a resistive touch panel, a capacitive touch panel, and a surface acoustic wave (SAW) touch panel, but the present invention is not limited thereto. The display device  100  comprises the infrared touch panel  200 , a computation device  110 , and a device casing  120 . As shown in  FIG. 1 , the lid of the device casing  120  of the display device  100  is removed, and thus a user can watch the elements, such as an infrared emitter  220  and an infrared receiver  224 , beneath the lid which is otherwise in place. The infrared touch panel  200  of the display device  100  comprises a rectangular liquid crystal display device module  228  and a rectangular infrared frame  230  disposed on the liquid crystal display device module  228 . A rectangular position-detecting surface  232  is defined on the liquid crystal display device module  228 . The position-detecting surface  232  is substantially aligned with an internal region defined by the infrared frame  230 . Two said infrared emitters  220  are disposed on two adjoined sides (such as the lower side and the left side) of the infrared frame  230 , respectively. Two said infrared receivers  224  are disposed on two other adjoined sides (such as the upper side and the right side) of the infrared frame  230 , respectively. 
     The infrared touch panel  200  further comprises a first control circuit  236 . The purpose of the first control circuit  236  is to allow the infrared emitters  220  to emit light beams in sequence, that is, from left to right, and from top to bottom, and allow the infrared receivers  224  to receive the light beams, respectively. Due to the aforesaid arrangement, the infrared emitters  220  scan the position-detecting surface  232  in sequence, thereby forming thereon a latticed infrared light beam matrix. The aforesaid elements constitute part of the conventional infrared touch panel and are not described in detail herein for the sake of brevity. 
     When an object is placed at a position of the position-detecting surface  232 , the object blocks a light path corresponding in position to the position. As a result, the light beams emitted from the infrared emitters  220  are prevented from being received by the infrared receivers  224 . Hence, the first control circuit  236  determines the x-coordinate of the object along X-axis  240  and the y-coordinate of the object along Y-axis  244  according to whether the infrared receivers  224  detect the light beams. 
     Referring to  FIG. 2 , there is shown a block diagram of the display device  100  of  FIG. 1 . The display device  100  comprises the computation device  110 , the infrared touch panel  200 , and the first control circuit  236 . In a preferred embodiment of the present invention, the computation device  110  is a computer. The computation device  110  comprises a central processing unit (CPU)  304 , a system memory  308 , and one or more I/O data ports  316 . In a preferred embodiment, the first control circuit  236  comprises a microprocessor  324 , a volatile memory (such as SRAM)  328 , and a non-volatile memory (such as flash memory)  332 . The display device  100  further comprises an input device  318  (such as a keyboard) and a loudspeaker (not shown). The central processing unit (CPU)  304  communicates with the system memory  308  through an address/data bus (not shown). The microprocessor  324  can be any commercially available or custom-made microprocessor. The system memory  308  includes, but is not limited to, one of SRAM, DRAM, ROM, PROM, EPROM, EEPROM, and flash memory. The aforesaid components can be conventional components, like the components of a conventional data processing system, and are configured to operate in a way described herein according to the present invention. 
     The system memory  308  further comprises a plurality of software and data for use in the computation device  110 , namely an operating system (not shown); an application (not shown); an input/output (I/O) device driver (not shown); and data (not shown). The I/O device driver typically comprises a software routine whereby the I/O device driver communicates with the I/O data ports  316 , a data storage device (not shown), and the system memory  308 . The application executes programs for performing various functions of the computation device  110 . The data include dynamic and static data for use in displaying the application, operating system, I/O device driver and other software programs stored in memory, and a portion of the data can be displayed by the liquid crystal display device module  228 . The aforesaid components/programs can be conventional components/programs, like plenty of conventional components/programs used in a data processing system, and can be configured to operate in a manner described herein according to the present invention. The infrared touch panel  200  is a conventional infrared touch panel. Since its liquid crystal screen does not generate light, it is necessary to display the liquid crystal screen by means of a backlight source. The liquid crystal display device module  228  of the infrared touch panel  200  comprises a backlight source, a light-guiding plate, a polarizing plate, liquid crystal, color film, and a polarizing plate. After the backlight source has emitted light, the light is dispersed evenly by the light-guiding plate before passing through the polarizing plate, the liquid crystal, the color film, and the polarizing plate to fall on the liquid crystal screen. The aforesaid components are part of a conventional panel and thus are not described in detail herein for the sake of brevity. 
     A point to note is that the display panel  200  is not limited to the infrared touch panel shown in  FIG. 1  and  FIG. 2 . In practice, the display panel  200  can come in different forms, such as a touch panel, a non-touch panel, a monitor, and a television, but the present invention is not limited thereto. 
     The infrared touch panel  200  further comprises a transparency adjusting apparatus  620  (see  FIG. 3 ) for adjusting the display transparency of the infrared touch panel  200 , and providing a solution for solving problems facing the prior art, such as reflection and glare. 
     Referring to  FIG. 3 , there is shown a cross-sectional view of the display device  100  of  FIG. 1 , the infrared touch panel  200 , the transparency adjusting apparatus  620 , and the device casing  120 . Referring to  FIG. 1  through  FIG. 3 , the infrared touch panel  200  comprises the liquid crystal display device module  228 , the infrared emitters  220 , and the infrared receivers  224 . The infrared emitters  220  emit infrared light. The infrared receivers  224  receive the infrared light and undergo light communication with the infrared receivers  224 . The infrared emitters  220  and the infrared receivers  224  form an infrared matrix in a conventional manner, so as to perform touch sensing, wherein its infrared emission direction and infrared reception direction are substantially parallel to the position-detecting surface  232  of the infrared touch panel  200 . 
     The first control circuit  236  (see  FIG. 1 ) receives and controls signals of the infrared emitters  220  and the infrared receivers  224  by means of a conventional circuit. A circuit board  560  is disposed at the bottom of a rear surface of the liquid crystal display device module  228  and adapted to carry the first control circuit  236 . 
     The infrared touch panel  200  comprises a connection circuit (not shown) for connecting the infrared emitters  220 , the infrared receivers  224 , and the first control circuit  236  according to related prior art. The connection circuit is similar to a connection circuit and is formed by an indium tin oxide (ITO) process in wide use. The ITO process typically comprises the steps of: forming an indium tin oxide layer on the touch screen panel  228 ; and patterning the indium tin oxide layer to form the connection circuit. However, the connection circuit can also be formed by any other conventional techniques, and thus the present invention is not restrictive thereof. 
       FIG. 3  also shows how the liquid crystal display device module  228  and the transparency adjusting apparatus  620  are arranged inside the device casing  120 . In an embodiment, the transparency adjusting apparatus  620  is a vapor chamber which has vapor received therein and confined thereto and is disposed above the liquid crystal display device module  228 . The transparency adjusting apparatus  620  is substantially rectangular and corresponds in shape to the liquid crystal display device module  228 . The vapor chamber  620  comprises a first transparent shell  628  and a second transparent shell  624  disposed on and covering the first transparent shell  628 . The first transparent shell  628  and the second transparent shell  624  together define a sealed space  636 . The second transparent shell  624  and the first transparent shell  628  are made of a transparent material, such as glass, transparent thermosetting resins, and plastics. The first transparent shell  628  and the second transparent shell  624  are panel-shaped with a thickness of 0.5 mm to 2 mm, but the present invention is not limited thereto. A means of coupling the second transparent shell  624  and the first transparent shell  628  together includes, but is not limited to, adhesion, fastening, and heat sealing. The second transparent shell  624  and the first transparent shell  628  can also be integrally formed as a unitary structure to form a transparent vapor chamber body, but the present invention is not limited thereto. The vapor chamber  620  further comprises a heater  632  that includes, but is not limited to, a coil heater and a resistive heater. The heater  632  and the first transparent shell  628  are fixed to each other by being coupled together with a fastener or glued together. The details and purposes of the aforesaid components are described and explained in detail later. 
     In an embodiment, the heater  632  is formed on the first transparent shell  628 , whereas the first transparent shell  628  and the second transparent shell  624  are arranged in a manner to face each other and sealed hermetically to form the sealed space  636 . Afterward, the sealed space  636  is vacuumed to an absolute pressure approximating zero, and then a liquid (that includes, but is not limited to, water, alcohol, ammonia, and cryogen) is contained in the sealed space  636  of the vapor chamber  620  in a vacuum state. By controlling the quantity of the liquid, it is feasible that the boiling point of the liquid is kept in a specific range. In an embodiment where the liquid is water, the boiling point of water ranges between −50° C. and 40° C., and preferably between −30° C. and 20° C. 
       FIG. 3  also shows that a light emitter  640  (such as an emitting LED) and a light receiver  644  (such as an receiving LED) are disposed on the two sides of the transparency adjusting apparatus  620 , electrically connected in the form of a closed loop, and are electrically connected to a second control circuit  536 . The second control circuit  536  can be a conventional circuit and is manufactured in the same way as the first control circuit  236 , but the present invention is not limited thereto. The second control circuit  536  receives signals from the emitting LED  640  and the receiving LED  644  and controls the signals thus received. The second control circuit  536  is disposed on the circuit board  560  (disposed at the bottom of the rear surface of the liquid crystal display device module  228 ). The details and purposes of the aforesaid components are described in detail later. The first control circuit  236  and the second control circuit  536  are separate. Alternatively, the first control circuit  236  and the second control circuit  536  are integrated to form a single circuit. 
     Referring to  FIG. 4 , there is shown a cross-sectional view of the display device  100  according to another preferred embodiment of the present invention. As shown in  FIG. 4 , the display panel  200  of the display device  100  is a non-touch panel. For example, the non-touch panel comes in various forms, but the present invention is not limited thereto. 
     Referring to  FIG. 5 , there is shown a schematic view of the operation of the transparency adjusting apparatus  620  of the display device  100  (see  FIG. 3 ), such as the operation of a vapor chamber, according to another preferred embodiment of the present invention. Referring to  FIG. 3  and  FIG. 5 , the display panel  200  of the display device  100  is an infrared touch panel. The vapor chamber  620  is manufactured in the way described above. The boiling point of the water in the vapor chamber  620  ranges between −50° C. and 40° C., preferably between −30° C. and 20° C., or is −10° C., for example. At room temperature, such as 25° C., the vapor chamber  620  is filled with transparent water vapor, and thus the vapor chamber  620  is transparent, thereby permitting the free passage of light. 
     After the vapor chamber  620  manufactured in the way described above has been installed on the display device  100 , adjustment of the transparency of the vapor chamber  620  requires starting the heater  632  to heat the sealed space  636  defined by the vapor chamber  620 ; as a result, not only does the saturation pressure of the water vapor in the vapor chamber  620  increase, but the boiling point of water at room temperature also increases (such as 40° C.), and in consequence vapor condenses on the second transparent shell  624  to form a condensed layer  700 . The condensed layer  700  reduces the transparency of the second transparent shell  624  in a variable manner. 
     Referring to  FIG. 5 , a light emitter  640 , a light receiver  644 , and the second control circuit  536  operate in conjunction with each other by a common conventional technique so as to measure the transparency of the vapor chamber  620  and send transparency-related data to the first control circuit  236 . The first control circuit  236  gives feedback to the heater  632  and thereby controls the saturation pressure of the vapor chamber  620 . Therefore, the transparency of the vapor chamber  620  is controlled effectively and precisely. 
     Referring to  FIG. 6 , there is shown a schematic view of the operation of the transparency adjusting apparatus  620  for the display device  100  (see  FIG. 4 ), such as the operation of a vapor chamber, according to yet another preferred embodiment of the present invention. Referring to  FIG. 4  and  FIG. 6 , the display panel  200  of the display device  100  is a non-touch panel, wherein vapor condenses on the second transparent shell  624  to form a condensed layer  710 . The condensed layer  710  reduces the transparency of the second transparent shell  624  in a variable manner. 
     Referring to  FIG. 7 , there is shown a schematic view of the transparency adjusting apparatus  620  provided in the form of a self-contained device according to a further preferred embodiment of the present invention. As shown in  FIG. 7 , the transparency adjusting apparatus  620  is directly coupled to the screen of a display device  720 . Alternatively, the top end of the transparency adjusting apparatus  620  is coupled to a strip (not shown) with a hook (not shown), wherein the hook is fastened to a hole (not shown) behind the screen. Alternatively, the transparency adjusting apparatus  620  is coupled to, and is confined to, the screen of the display device  720  by a frame (not shown), thereby effectuating transparency adjustment. The transparency adjusting apparatus  620  further comprises a universal serial bus (USB). The transparency adjusting apparatus  620  is connected to the display device  720  via the universal serial bus (USB) by a conventional technique, so as to achieve transparency adjustment. The universal serial bus (USB) is part of the related prior art and thus is not described in detail herein for the sake of brevity. 
     Due to its aforesaid design, the present invention achieves an anti-reflection anti-glare effect, features a simple manufacturing process, adjusts the transparency of a display device surface precisely, and reduces its etching/coating process significantly, thereby providing an environmentally friendly solution. 
     The foregoing preferred embodiments are provided to illustrate and disclose the technical features of the present invention, and are not intended to be restrictive of the scope of the present invention. Hence, all equivalent variations or modifications made to the foregoing embodiments without departing from the spirit embodied in the disclosure of the present invention should fall within the scope of the present invention as set forth in the appended claims.

Technology Category: 3