TW200532308A - Dual-sided viewable liquid crystal display - Google Patents

Abstract

A dual-sided viewable liquid crystal display (LCD). The LCD includes a liquid crystal (LC) cell, a light source, and an optical film. The light source is disposed over the front side of the LC cell to provide the light passing through therein. The optical film is disposed on the rear side of the LC cell and opposite to the light source. When the light passes through the LC cell, the front side of the LC cell is in a reflective display mode using the optical film as a reflective layer and the rear side of the LC cell is in a transmissive display mode using the optical film as a transmissive layer.

Description

200532308 V. Description of the invention α) —- [Field of invention] The present invention relates to a liquid crystal display device (Uquid crystai d1Splay, LCD), and in particular to a display device capable of displaying on both sides of a liquid crystal panel (dUai- slded Vlewable). [Previously, it has been displayed by a wide range of people, both of which are lacking 0,, positive, and negative are available in the market.) The transmission method is to make the thickness of the positive and negative circuit match the line display device, and make the technology. (LCD) has the advantages of light weight, thinness, and power saving. It is widely used in portable personal computers, digital cameras, projectors, personal computers (PM), and mobile phones. Regardless of whether the LCD monitor is transmissive or reflective, it is single-sided. However, with the continuous development of electronic products, displaying data on both sides of the display screen has become a requirement for many products. For example, there is a foldable mobile phone (folder type m〇biie), which has liquid crystal display screens on the inner and outer sides of the cover. When manufacturing such electronic products with double-sided displays, it is generally As the main structure, two sets of liquid crystal display panels are used to display the data on both sides. Because of this, the above method must provide two sets of drives to drive = the above two independent liquid crystal display panels. In addition to increasing the product and weight In addition, it also increases the manufacturing cost relatively, and does not require the need for stationary electronic products. National Patent No. 6, 580, 4 88 discloses a liquid crystal display with a double-sided display only using a liquid crystal display panel and a partial shielding method. The front and back sides of the LCD panel can be displayed in reflective mode.

Page 5 200532308 V. Description of the invention (2) However, the size of the area will inevitably reduce the size of the liquid crystal display, or it is necessary to increase the size of the display panel on both the front and back sides of the overall liquid crystal display panel. [Summary of the Invention] In view of this, an object of the present invention is to provide a liquid crystal display device capable of double-sided display, which utilizes a single liquid crystal display panel structure to realize the demand of mobile electronic products. A further object of the present invention is to provide a liquid crystal display device which can display on both sides, which has both a reflection mode and a transmission mode display mode, and

There is no need to reduce the size of the display area on the front and back of the liquid crystal display device or increase the size of the liquid crystal display device.

In order to achieve the above object, the present invention provides a liquid crystal display device capable of double-sided display, which includes: a first substrate, a second substrate, a liquid crystal layer, a first polarizer, a light source device, an optical film, And a second polarizer. The second substrate is disposed opposite to the first substrate, and the liquid crystal layer is interposed between the first substrate and the second substrate. The first polarizer is disposed on the first substrate and faces the liquid crystal layer. The light source device is disposed on the first polarizer and is opposite to the first substrate: to provide a light source to pass through the liquid crystal layer. The optical film is disposed on the second substrate and faces the liquid crystal layer. The second polarizer is disposed on the optical film and is opposite to the second substrate. When the light source passes through the liquid crystal layer from the first polarizer, an optical film is used as a reflective layer, so that the first substrate side is in a reflective mode for display, and an optical film is used as a penetrating layer, so that the second substrate side is caused to pass through. Mode display. Among them, the above-mentioned liquid crystal display device capable of double-sided display further includes two viewing angles

200532308 V. Description of the invention (3) One of the compensation films is disposed on the first polarizer and opposite to the first substrate, and the other is disposed on the second polarizer and opposite to the second substrate, or is disposed on the optical film and the second Between substrates. According to the above object, the present invention provides a liquid crystal display device capable of displaying on both sides, which includes a first substrate, a second substrate, a liquid crystal layer, first and second polarizers, and first and second substrates. Two backlight units. The second substrate is disposed opposite to the first substrate, and the liquid crystal layer is sandwiched between the first substrate and the second substrate. The first and second polarizers are respectively disposed on the first substrate and the second substrate and are opposite to the liquid crystal layer. The first and second backlight devices are respectively disposed on the first polarizer and the second polarizer, and the first backlight device is opposed to the first substrate and the second backlight device is opposed to the second substrate, so as to provide a light source from the first polarizer. Or the second polarizer passes through the liquid crystal layer, so that the second substrate side or the first substrate side is in a transmission mode display. The liquid crystal display device capable of double-sided display further includes a two-view-angle compensation film, one of which is disposed on the first polarizer and opposite to the first substrate, and the other is disposed on the second polarizer and opposite to the second substrate. In order to make the above-mentioned objects, features, and advantages of the present invention more comprehensible, the following describes specific embodiments in combination with the accompanying drawings for detailed description as follows:

0632-A50041TWF (version 4.5); AUQ3Q7_; SPIN.ptd page 7 200532308 V. Description of the invention (4) Please refer to Figure 1a, which shows a liquid crystal display device that can display on both sides. The liquid crystal display device 100 includes a liquid crystal cell (LCe 1 1) 101, two polarizers 108 and 114, a light source device 110, an optical film 112, and a control device 116. The liquid crystal cell 100 includes a first substrate 102, a first substrate 104, and a liquid crystal layer 106. The first and second substrates 102 and 104 are transparent substrates, such as glass or quartz substrates, and the two substrates 102 and 104 are oppositely disposed in parallel. Generally, one of the first and second substrates 102 and one of the two substrates is provided with a filter and a light filter (CF) (commonly referred to as a filter substrate), and the other A plurality of transistors (not shown) and corresponding day electrode (not shown) are formed on the front surface of the substrate (commonly referred to as an array substrate). The front sides of the two substrates 102 and 104 face each other. The liquid crystal layer 106 is sandwiched between the front surface of the first substrate 102 and the front surface of the second substrate 104 to form a liquid crystal cell 101. Here, the liquid crystal mode can be reversed

Twisted nematic (TN), vertical alignment (VA), in-plane switching (ICP), optically compensated bend (OCB), and other liquid crystals that can be used for display mode. The polarizer 108 is disposed on the back surface of the first substrate 102 and is opposed to the liquid crystal layer 106. Next, a viewing angle compensation film 10 9 (shown as a set state in this embodiment) may be selectively provided on the polarizer i 08 so as to be opposite to the first substrate 102. The light source device 1 1 〇 is disposed on the polarizer i 08 or the viewing angle compensation film 10 9 (this embodiment is shown as being disposed on the viewing angle compensation film 丨 09) and is also opposite to the first substrate 1 〇 2 (That is, a polarizer! 0 8, the viewing angle compensation film 10, and the light source device 110 are sequentially arranged on the back of the first substrate.

0632-A5004lTWF (version 4.5); AU0307040; SPIN.ptd page 8 200532308 V. Description of the invention (5) side), which provides a light source to pass through the liquid crystal layer 106 through a polarizer 108 for displaying images. The optical waist 1 12 is disposed on the back surface of the second substrate 104 and is opposite to the liquid crystal layer 106. Here, the optical film 112 has a function of partially reflecting and partially transmitting the light source, such as a thin film beam splitter or a brightness enhancement film. Furthermore, a polarizer 114 is disposed on the optical film 112 and is opposite to the second substrate 104. In addition, a viewing angle compensation film 11 5 (shown as a setup in this embodiment) may be selectively provided on the polarizer 11 4, and it is opposite to the second substrate 104 (ie, the optical film 11 2 , The polarizers 1 14 and the viewing angle compensation film 115 are sequentially disposed on the back side of the second substrate 104). Alternatively, the viewing angle compensation film 11 5 (not shown) may be selectively provided between the optical film 112 and the second substrate 104. In addition, when the above-mentioned optical film 1 12 is a brightness enhancement film, in order to recycle the light source to improve the display brightness, the main technologies can be divided into retroreflective and cholesteric liquid crystal-based reflective) two. The former mainly deals with P and S linear polarization, while the latter deals with left-handed and right-handed circularly polarized light. "DBEF" (dual brightness enhancement film) manufactured by 3M Corporation in the United States uses retro-reflective technology. This optical brightening film system allows P-line polarized light to penetrate and reflect S-line polarized light. The reflected S linear polarized light can be converted into P and S linear polarized light after returning to the light source device, so as to achieve the effect of light recycling and reuse and improve the brightness. In addition, "NIP0CS" manufactured by Nitto Denko in Japan uses the cholesterol liquid crystal reflection technology.

0632-A50041TWF (version 4.5) ·, AU0307040; SPIN.ptd Page 9 200532308 V. Description of the invention (6) This optical brightening film system can allow 50% right-handed circularly polarized circularly polarized light to achieve similar DBEF increase Fruiting teeth with bright film. Sub-reflection 5 left In this embodiment, the optical film can be a thin film eight film method, which is set on the second base by the characteristics of the thin film beam splitter or brightening, two ^ ^ W 70 transmission light source; When the light source self-view compensation film J 0 9 which is partially set to 1 1 0 passes through the polar field light source device, the optical film 112 is used as a reflective layer first == night crystal cell 101 and the light source device 110 of the front light source passes through. Make; t source; shoot to the display as a reflection. That is, the observer can obtain the image information through the self-reflecting reflective light source 11 〇a. For example, when the 12 reflection 108 and the liquid crystal cell 101, the optical film 112 can also be used. Light source device !!. Penetration out: I :: 』The m side of the substrate is displayed in the penetrating mode. In other words, if the film 112 passes through this transparent / transmitting source U ° b to obtain image data for the purpose of double-sided display. The liquid of the moon said that the display device m and the reachable control device 116 are coupled to the first substrate 102 and the second between them: to control the timing of the image displayed on both sides, so that the observer can obtain the same observation surface Correct image information. , B According to the embodiment of the present invention, the liquid crystal display capable of double-sided display can be achieved by: using an optical film as the radiation layer and the transmission layer to achieve reflection and transmission modes. Γ Γ #, so only A single liquid crystal cell can achieve the purpose of double-sided display. Compared with the conventional two independent LCD display panel architecture,

200532308 V. Description of the invention (7) It is very suitable for mobile electronic products because it has the advantages of lightness, thinness, and low power consumption. Furthermore, since the liquid crystal display device capable of double-sided display in this embodiment has a display mode of reflection and transmission, there is no need to reduce the size of the liquid crystal display device as is the case with a conventional double-sided liquid crystal display device with a single liquid crystal display panel architecture. The size of the opposite display area may increase the size of the liquid crystal display device. Second Embodiment A liquid crystal display device capable of double-sided display according to a second embodiment of the present invention will be described with reference to Figs. 2a and 2b. Please refer to FIG. 2a ', which shows a liquid crystal display device capable of double-sided display. The liquid display device 2000 includes a liquid crystal cell 201, first and second polarizers 208 and 212, first and second backlight devices 21 and 214, and a control device 216. The liquid crystal cell 201 includes a first substrate 202, a second substrate 204, and a liquid crystal layer 206. The first and second substrates 202 and 204 are transparent substrates, such as glass or quartz substrates, and the two substrates are disposed in parallel and oppositely. Generally, one of the first and second substrates 202 and 204 is provided with a color filter (CF) (commonly referred to as a filter substrate) on the front surface, and the front surface of the other substrate is formed with A plurality of transistors (not shown) and corresponding day element electrodes (not shown) (commonly referred to as an array substrate). The front surfaces of the two substrates 102 and 104 face each other. The liquid crystal layer 206 is sandwiched between the first substrate 202 and the second substrate 204 to constitute a liquid crystal cell 20.1. Here, the liquid crystal mode may be TN, VA, ICP, 0CB, and other liquid crystal modes that can be used for display. The first and second polarizers 208 and 21 2 are respectively disposed on the first substrate

〇632-A50041TWF (version 4.5); AU0307040; SPIN.ptd Page 11 200532308 V. Description of the invention (8) On the back of the 202 and the second substrate 204, and opposite to the liquid crystal layer 206, respectively. In addition, a viewing angle compensation film 20 (optionally shown in this embodiment) can be provided on the first polarizer 20 8, and is opposite to the first substrate 2 0 2 (that is, The first polarizer 208 and the viewing angle compensation film 209 are sequentially disposed on the back side of the first substrate 202). Furthermore, a viewing angle compensation film 2 1 5 (shown as a set state in this embodiment) may be selectively disposed on the second polarizer 2 1 2 and is opposite to the second substrate 2 0 4 (that is, The second polarizer 212 and the viewing angle compensation film 2 15 are sequentially arranged on the back side of the second substrate 20 04). Then, the first and second backlight devices 210 and 214 are respectively provided on the viewing angle compensation film 209 and the viewing angle. On the compensation film 215, the first backlight device 21o is opposed to the first polarizer 2 08 and the second backlight device 2 1 4 is opposed to the second polarizer 2 1 2 to provide a light source from the first polarizer 2 The 0 8 or the second polarizer 2 i 2 passes through the liquid crystal cell 201 for displaying an image. In this embodiment, the first light source device 2 1 0 may be turned on and the second light source device 214 may be temporarily turned off, so that the light source 210 a sequentially passes through the first polarizer 2 0 8 and the liquid crystal cell 2 0 1 from the viewing angle compensation film 20 9. , The second polarizer 2 12 and the second light source device 2 14 and penetrate out, so that the side of the second substrate 20 04 is displayed in a transmission mode. That is, the first light source device 2 10 is used as a backlight source, so that an observer can obtain image information on the second substrate 204 side through the light source 2 10 a, as shown in FIG. 2a. On the other hand, the second light source device 214 may be turned on and the first light source device 2 10 may be temporarily turned off, so that the light source 2 1 4a passes through the second polarizer 212, the liquid crystal cell 201, the first The polarizer 208 and the first light source device 210 penetrate out, so that the 202 side of the first substrate is located at

0632-A50041TWF (4.5®; AU0307040; SPlN.ptd page 12 200532308 V. Description of the invention (9) Transmission mode display. That is, the second light source set 214 is used as a backlight and the light source 214a is transmitted through the first-substrate 202 Obtain the image on the side: set it to 20w. In this way, the liquid crystal display device 200 of the present invention can also achieve the purpose of double-sided display. The plate 204 is the same as the ground, and the control device 1 21 6 series is connected to the first The shadow silly sniper who is used to control the double-sided display between one substrate and the second substrate 204 can obtain the correct image data at different observation planes. Mr. Wang < Observes that according to this embodiment The liquid that can be displayed on both sides means that two backlight devices are used as the backlight in turn, and only one single-liquid crystal cell can be used to achieve the obvious display. As described in the first embodiment, this embodiment : Purpose. The display device does not need to display the liquid crystal display of the double-sided liquid crystal display as in the conventional display. The size of the LCD display device is not limited, although the present invention has been limited to the present invention by a preferred embodiment. Familiar with this technique 蓺 ° = 上 ， 然 其If it is not used within the scope and scope, it can be changed and modified ^ It is determined by the scope of the patent application attached without departing from the essence of the present invention = $ The protection scope of the present invention 0632-A50041TWF (version 4.5); AU0307040; SPIN.ptd Page 13 200532308 Brief description of the drawings Figure 1a shows the liquid crystal display device capable of double-sided display and the display state on one side of the first embodiment of the present invention. Figure 1b is a drawing The liquid crystal display device capable of double-sided display according to the first embodiment of the present invention and the display state of the other opposite side thereof are shown in FIG. 2a, which shows the liquid crystal display device capable of double-sided display according to the second embodiment of the present invention and one The display state on the side. Fig. 2b is a diagram showing a liquid crystal display device capable of double-sided display and the display state on the other opposite side according to the second embodiment of the present invention. [Symbol description] 1 0 0, 2 0 0 ~ liquid crystal display Device; 1 0, 2 0 1 ~ liquid crystal cell; 10 2, 20 2 ~ first substrate; 104, 204 ~ second substrate; 106, 2 06 ~ liquid crystal layer; 108, 114 ~ polarizer 1 0 9 2 0 9 11 5 2 15 5 viewing angle compensation film 11 0 light source device 11 Oa reflected light ; 11 Ob~ penetrating light source; an optical film 2 ~ 11; 1 6 ~ control apparatus 11 6,2; 20 8~ first polarizer; a first 210~ backlight device;

0632-A50041TWF (version 4.5); AU0307040; SPIN.ptd page 14 200532308 Brief description of the diagram 210a, 214a ~ light source; 2 1 2 ~ second polarizer; 2 1 4 ~ second backlight device. 0632-A50041TWF (version 4.5); AU0307040; SPIN.ptd page 15

Claims (1)

200532308 t. Patent application scope 1. A liquid crystal display device capable of double-sided display, including a first substrate; a second substrate opposite to the first substrate; a liquid crystal layer sandwiched between the first substrate and Between the second substrates; a first polarizer is disposed on the first substrate and is opposite to the liquid crystal layer; a light source device is disposed on the first polarizer and is opposite to the first substrate to provide a A light source passes through the liquid crystal layer; an optical film is disposed on the second substrate and is opposite to the liquid crystal layer; a second polarizer is disposed on the optical film and is opposite to the second substrate. '' When the light source passes through the liquid crystal layer from the first polarizer, the optical film is used as a reflective layer, so that the first substrate side is in a reflective mode, and the optical film is used as a transmission layer, so that The second substrate side is displayed in a transmission mode. 2 · The liquid crystal display device capable of double-sided display as described in item 1 of the scope of patent application, further comprising a viewing angle compensation film disposed on the first polarizer and opposite to the first substrate. 3 · The liquid crystal display device capable of double-sided display according to item 1 of the scope of patent application, further comprising a viewing angle compensation film disposed on the second polarizer and opposite to the second substrate, or on the optical film And the second substrate. 4 · LCD display with double-sided display as described in item 1 of the scope of patent application Page 16 200532308 VI. Scope of patent application Shows the device and its membrane. 5 · If the device is declared, its NIP0CS is brightened 6 · If the device is claimed, it is 7 · If the device is declared, between the substrates, 8 ·-a kind of the first optical film is made by 3M DBEF Brightening Solution and Liquid Crystal Display with Double-sided Display as described in Item 1 of the Patent Scope This optical film is a liquid crystal display with double-sided display as described in Item 1 of Patent Scope manufactured by Japan Nitto Denko. The optical film is a thin film beam splitter. The double-sided display liquid crystal display device described in the first item of the patent scope is coupled to the first substrate and the second double-sided display image sequence processing. The liquid crystal display device shown includes: the first substrate is disposed oppositely; between the first substrate and the second substrate; a sheet is disposed opposite the first substrate and the second crystal layer respectively; and the device is disposed separately The first polarizer and the backlight device are opposite to the first substrate and the second substrate is opposite to provide a light source to pass through the liquid crystal layer from the first sheet, so that the second substrate is displayed in a transparent mode. The liquid crystal display corner compensation film capable of double-sided display as described in item 8 is provided on the first polarizer and the middle film is requested. Please include the first base plate and the second plate. Control to control the double-sided display board; the board, and 'cool = polarized light and the liquid = backlight, and the second ~ polarized side is located on the patented substrate and divided into the second polarized backlight polarizer or the first 9 · If the claim device is opposite to the first substrate and the light film device or the base includes a view 0632-A50041TWF (version 4.5); AU0307040; SPIN.ptd page 17 200532308 VI. Patent application scope 1 0 · As described in the patent application scope item 8, the liquid crystal display device with double-sided display can include a viewing angle compensation film Is disposed on the second polarizer and is opposite to the second substrate. 1 1 · The liquid crystal display device capable of double-sided display as described in item 8 of the scope of patent application, further comprising a control device coupled between the first substrate and the second substrate for controlling the double-sided display. Image timing processing. 0632-A50041TWF (version 4.5); AU0307040; SPIN.ptd page 18