JP5203579B2 - Liquid crystal display - Google Patents

Description

  The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device having an effective display area without uneven brightness.

  FIG. 1 is a diagram illustrating an example of a conventional liquid crystal display device 1.

  A liquid crystal display device 1 shown in FIG. 1 includes a liquid crystal panel 2 and a point light source 9. In the liquid crystal panel 2, liquid crystal is sandwiched between substrates by a seal member 3 and a sealing portion 4. Further, the light emitted from the point light source 9 diffuses into the liquid crystal panel 2 as indicated by an arrow 5. However, in the regions 6 and 8 in the figure, the light is not sufficiently diffused and the luminance is lowered. On the other hand, in the region 7 in the figure, the luminance is increased due to being close to the light source, and an eyeball phenomenon may occur. . As described above, the conventional liquid crystal display device 1 has a problem that luminance unevenness occurs as a whole.

  Therefore, an attempt has been made to eliminate luminance unevenness by mixing light diffusing particles into a light source side sealing member and diffusing light by the light diffusing particles (see, for example, Patent Document 1). However, when the light diffusing particles are mixed with the light source side sealing member, light diffusion occurs at the light source side sealing member. Therefore, light does not reach the entire liquid crystal panel, and the luminance of the regions 6 and 8 in FIG. The decrease can be prevented, but conversely, a decrease in luminance occurs at a location away from the light source. On the other hand, if a small amount of light diffusing particles is mixed with the sealing member on the light source side, sufficient light diffusion does not occur, and it is impossible to prevent a decrease in luminance in the regions 6 and 8 in FIG. there were.

  Also, provide a predetermined gap between the light source and the liquid crystal, and form a rough crushed surface processed into a frosted glass on the glass substrate between them, and diffuse the light using the rough crushed surface to eliminate uneven brightness (See, for example, Patent Document 2). However, it is difficult to process only a predetermined portion of the substrate, and the cost is increased.

  In addition, an interval is provided between the liquid crystal and the effective display area, and a polymer dispersed liquid crystal is disposed between them or a scattering segment is provided by the polymer dispersed liquid crystal to diffuse light by the liquid crystal itself or the scattering segment. Attempts have been made to eliminate luminance unevenness (see, for example, Patent Document 2). However, the liquid crystal has to be sealed separately for the scattering segment by the polymer dispersed liquid crystal and / or the polymer dispersed liquid crystal simply provided between the liquid crystal and the effective display area is light. There was a problem that it was difficult to use effectively.

Japanese Patent Laid-Open No. 11-183888 (FIG. 1) Japanese Patent Laid-Open No. 2000-162672 (FIGS. 4, 5 and 6)

  Accordingly, an object of the present invention is to provide a liquid crystal display device capable of appropriately diffusing the light irradiated from the light source by the light diffusion region of the polymer dispersed liquid crystal and eliminating the luminance unevenness. To do.

  In order to solve the above problems, a liquid crystal display device according to the present invention has an effective display region for displaying information, a light diffusion region continuous with the effective display region, and a polymer dispersed liquid crystal between a pair of substrates. And a sealing member disposed around the polymer dispersed liquid crystal to seal the polymer dispersed liquid crystal so as to obtain an effective display region and a light diffusion region between the pair of substrates. A light source for irradiating light from the side surface of the liquid crystal panel through a polymer dispersed liquid crystal sealed in the light diffusion region, and the shape of the light diffusion region is determined based on the light emission characteristics of the light source It is characterized by being.

  In order to solve the above problems, a liquid crystal display device according to the present invention has an effective display area for displaying information, a light diffusion area continuous with the effective display area, and a polymer dispersion between a pair of substrates. A liquid crystal panel sandwiched between a pair of substrates and a seal disposed around the polymer dispersed liquid crystal to seal the polymer dispersed liquid crystal so that an effective display region and a light diffusion region are obtained between a pair of substrates It has a light source for irradiating light from the side surface of the liquid crystal panel through a member and a polymer dispersed liquid crystal sealed in the light diffusion region, and the shape of the light diffusion region is effectively displayed with the light source side as a vertex. It has a kamaboko shape with the region side as the base.

  Furthermore, in order to solve the above problems, a liquid crystal display device according to the present invention has an effective display area for displaying information, a light diffusion area continuous with the effective display area, and a polymer dispersion between a pair of substrates. A liquid crystal panel sandwiched between a pair of substrates and a seal disposed around the polymer dispersed liquid crystal to seal the polymer dispersed liquid crystal so that an effective display region and a light diffusion region are obtained between a pair of substrates It has a light source for irradiating light from the side of the liquid crystal panel through a member and a polymer dispersed liquid crystal sealed in the light diffusion region, and the light diffusion region has a top side on the light source side for effective display It has a substantially trapezoidal shape with the region side as the base.

  Furthermore, in order to solve the above problems, a liquid crystal display device according to the present invention has an effective display area for displaying information, a light diffusion area continuous with the effective display area, and a polymer dispersion between a pair of substrates. A liquid crystal panel sandwiched between a pair of substrates and a seal disposed around the polymer dispersed liquid crystal to seal the polymer dispersed liquid crystal so that an effective display region and a light diffusion region are obtained between a pair of substrates And a light source for irradiating light from the side surface of the liquid crystal panel through a polymer dispersed liquid crystal sealed in the light diffusion region, and the light diffusion region has a substantially elliptical shape. It is characterized by.

  Furthermore, in order to solve the above problems, a liquid crystal display device according to the present invention has an effective display area for displaying information, a light diffusion area continuous with the effective display area, and a polymer dispersion between a pair of substrates. A liquid crystal panel sandwiched between a pair of substrates and a seal disposed around the polymer dispersed liquid crystal to seal the polymer dispersed liquid crystal so that an effective display region and a light diffusion region are obtained between a pair of substrates And a light source for irradiating light from the side surface of the liquid crystal panel through a polymer dispersed liquid crystal sealed in the light diffusion region, and the light diffusion region has a substantially rectangular shape It is characterized by being.

  In the liquid crystal display device according to the present invention, since the light irradiated from the light source is appropriately diffused by the light diffusion region of the polymer-dispersed liquid crystal having a predetermined shape, it is possible to eliminate uneven brightness at low cost. It became. Furthermore, in the liquid crystal display device according to the present invention, the shape of the light diffusion region can be changed in accordance with the light emission characteristics such as the light emission intensity distribution of the light source, so that the luminance unevenness can be surely eliminated.

  Hereinafter, a liquid crystal display device according to the present invention will be described with reference to the drawings.

  FIG. 2 is a diagram showing a schematic configuration of the liquid crystal display device 10 according to the present invention.

  2A is a front view of the liquid crystal display device 10, and FIG. 2B is a cross-sectional view taken along line AA 'in FIG. As shown in FIG. 2, the liquid crystal display device 10 includes a liquid crystal panel 40 and a W (white) LED 30 that functions as a point light source disposed on a side surface of the liquid crystal panel 40.

  In the liquid crystal panel 40, the pair of glass substrates 21 and 22 are joined by the sealing member 100, and the liquid crystal 23 is injected from the opening 101 of the sealing member 100 so as to be sandwiched between the pair of glass substrates. It is sealed by. A prism sheet 24 is disposed on the viewing side of the liquid crystal panel 40 (upper side in FIG. 2B), and a reflecting plate 25 is disposed on the opposite side. The liquid crystal panel 40 is an active-driven TFT type liquid crystal display unit, and can display 2.4 inches and a QVGA size (350 × 240 pixels) in the effective display area 26. In addition, a plurality of signal electrodes and a plurality of scanning electrodes made of a transparent conductor are patterned on the inside of the pair of glass substrates 21 and 22 of the liquid crystal panel 40, and a portion where the signal electrodes and the scanning electrodes overlap is a display pixel. .

  Here, a polymer dispersed liquid crystal having a haze of 88% is used as the liquid crystal 23, but a PNLC liquid crystal can also be used. In the polymer-dispersed liquid crystal, liquid crystal molecules are randomly arranged in a state where no voltage is applied. Therefore, when white light is incident, the incident light is scattered and observed as a cloudy state from the outside. Further, in the polymer dispersed liquid crystal, liquid crystal molecules are aligned in the direction of an electric field when a voltage is applied, so that incident light is transmitted and is observed as a transparent state from the outside.

  The light emitted from the W color LED 30 enters from the side surface of the liquid crystal panel 40. The light that has entered the liquid crystal panel 40 from the W color LED 30 is configured to be able to irradiate the entire effective display area 26 of the liquid crystal panel 40 while being repeatedly reflected by the prism sheet 24, the reflecting plate 25, and the like. Further, since light can be incident from the side surface of the seal member 100, it is not necessary to arrange a backlight on the back side of the liquid crystal panel 40, and a thin liquid crystal display device that can be illuminated can be realized.

  The seal member 100 includes a spacer for adjusting the gap between the pair of glass substrates 21 and 22, a filler for scattering light from the W color LED 30, an adhesive, and the like. As the spacer and filler, those having physical properties of silica (refractive index 1.35 to 1.45) or plastic (refractive index 1.4 to 2.0) can be used. As a result, the liquid crystal 23 is maintained at a desired thickness. For PNLC, a thickness of 10-30 μm is preferred.

  Further, the four sides of the seal member 100 were formed to have substantially the same thickness (for example, about 0.8 mm). However, the W-color LED 30 side of the seal member 100 gradually spreads from the portion closest to the W-color LED 30 in a quadratic curve and continues to the effective display region 26. Curved along the outer shape. In other words, the light diffusion region 120 has a semi-cylindrical shape with the W-color LED 30 side as a vertex and the effective region 26 side as a base.

  Next, a schematic manufacturing method of the liquid crystal panel 40 shown in FIG. 2 will be described.

  First, a seal member 100 is formed by screen printing inside one of a pair of glass substrates 21 and 22 on which a plurality of signal electrodes and a plurality of scanning electrodes are formed by a transparent conductor, and the pair of glass substrates 21 and A spacer is spread over the entire other inner side of 22. Next, a pair of glass substrates are overlapped and bonded. Next, the polymer dispersed liquid crystal 23 is injected from the opening 102 of the seal member 100 and sealed with the sealant 27. Next, UV light is irradiated from the glass substrate 22 side to crosslink the monomers in the polymer dispersed liquid crystal material, thereby creating a polymer network. Next, the prism sheet 24 is disposed outside the glass substrate 21 of the liquid crystal panel 40. Next, the reflection plate 25 is bonded to the outside of the glass substrate 22.

  The light incident on the liquid crystal panel 40 from the W color LED 30 is sufficiently diffused by the light diffusion region 120 of the polymer dispersed liquid crystal provided on the W color LED side of the seal member 100, so that the region 6 in FIG. 8 does not cause a decrease in luminance, does not cause excessive luminance concentration in the portion corresponding to the region 7 in FIG. 1, and does not cause uneven luminance in the effective display region 26 as a whole. . Therefore, in the present embodiment, it is possible to efficiently use the light emitted from the W color LED 30.

  As described above, in the present embodiment, the light scattering region 120 is provided by the polymer dispersed liquid crystal in a state where no voltage is applied continuously to the effective display region 26, and the light incident from the W color LED 30 is transmitted by the light scattering region 120. By sufficiently entering the effective display area 26 after being scattered, luminance unevenness in the effective display area 26 is prevented. In this embodiment, the seal member 100 includes a filler and the seal member 100 itself has a function of diffusing light. However, the seal member 100 itself is transparent and does not have a light diffusion function. Also good.

  FIG. 3 is a diagram showing a schematic configuration of another liquid crystal display device 11 according to the present invention.

  The difference between the liquid crystal display device 11 shown in FIG. 3 and the liquid crystal display device 10 shown in FIG. 2 is that the shape of the light diffusion region 121 of the liquid crystal panel 41 is different. In this embodiment, the same number is attached | subjected to the structure similar to FIG.

  The seal member 102 in this embodiment is made of the same material as that of the liquid crystal display device 10 shown in FIG. 2, and the four sides are formed to have substantially the same thickness (for example, about 0.8 mm). However, the W-color LED 30 side of the seal member 102 has an outer shape of the light diffusion region 121 having a shape that gradually extends from the portion closest to the W-color LED 30 in a hyperbola and continues to the effective display region 26. Is curved along. In other words, the light diffusion region 121 has a substantially trapezoidal shape (Mt. Fuji shape) in which the W LED 30 side is a top side, the effective region 26 side is a bottom side, and the left and right sides are concave arcs.

  The light incident on the liquid crystal panel 41 from the W color LED 30 is sufficiently diffused by the light diffusion region 121 of the polymer dispersion type liquid crystal provided on the W color LED side inside the seal member 102, so the region of FIG. The luminance corresponding to 6 and 8 does not decrease and excessive luminance concentration does not occur in the portion corresponding to the region 7 in FIG. There is no. Therefore, in the present embodiment, it is possible to efficiently use the light emitted from the W color LED 30.

  Thus, in this embodiment, the light scattering region 121 is provided by the polymer dispersed liquid crystal 23 in a state where no voltage is applied continuously to the effective display region 26, and the light incident from the W-color LED 30 is converted into the light scattering region 121. After being sufficiently scattered by the incident light, it is incident on the effective display area 26, thereby preventing uneven brightness in the effective display area 26.

  FIG. 4 is a diagram showing an example of the emission intensity distribution of the W color LED.

  In FIG. 4, the y-axis indicates the amount of light, and the x-axis indicates the angle from the light source. Note that the point P indicates the LED light directly above (0 °), the curve L1 indicates the light amount distribution of the W color LED having a narrow light amount distribution, and the curve L2 indicates the light amount distribution of the W color LED having a broad light amount distribution. Is shown.

  When the light amount distribution of the W color LED to be used is as shown by the curve L1, it is preferable that the light scattering region on the W color LED 30 side of the seal member 100 has a substantially trapezoidal shape as shown in FIG. When the light quantity distribution of the color LED is as indicated by the curve L2, it is preferable that the light scattering region of the seal member 100 on the W color LED 30 side has a kamaboko shape as shown in FIG. This is because, in the light source of the curve L1 type with a narrow light amount distribution, since the light amount becomes sharp at a large angle from the center, a substantially trapezoidal shape in which the light scattering region at a large angle from the center is thin is preferable. It is. Further, in the light source of the curve L2 type with a broad light amount distribution, the light amount is large even at a large angle from the center, and therefore, a kamaboko type with a thick light scattering region at a large angle from the center is preferable. As described above, in the liquid crystal display device according to the present invention, it is possible to select an optimal seal member shape according to the light emission characteristics of the LED in order to eliminate luminance unevenness.

  FIG. 5 is a diagram showing a schematic configuration of another liquid crystal display device 12 according to the present invention.

  The difference between the liquid crystal display device 12 shown in FIG. 5 and the liquid crystal display device 10 shown in FIG. 2 is that two LEDs are used and the shape of the light diffusion region 122 of the liquid crystal panel 42 is different. The W color LED 31 is the same LED as the W color LED 30 described above, and the two LEDs are used in order to obtain higher luminance in the effective display area 26. In this embodiment, the same number is attached | subjected to the structure similar to FIG.

  The seal member 103 in this embodiment is made of the same material as that of the liquid crystal display device 10 shown in FIG. 2, and the four sides are formed to have substantially the same thickness (for example, about 0.8 mm). However, the W-color LED 30 side of the seal member 103 has a shape that gradually spreads in a quadratic curve from the portion closest to the W-color LEDs 30 and 31 and continues to the effective display area 26. It is curved along the outer shape of the light diffusion region 122. In other words, the light diffusion region 122 has a two-stage kamaboko shape with the W-color LEDs 30 and 31 as the apex and the effective region 26 as the base.

  Since the light incident on the liquid crystal panel 42 from each of the W color LEDs 30 and 31 is sufficiently diffused by the light diffusion region 122 of the polymer dispersed liquid crystal provided on the W color LED side inside the seal member 103, The luminance corresponding to the regions 6 and 8 in FIG. 1 does not decrease in luminance, and excessive luminance concentration does not occur in the portion corresponding to the region 7 in FIG. Unevenness does not occur. Therefore, in the present embodiment, it is possible to efficiently use the light emitted from the W color LEDs 30 and 31.

  Thus, in this embodiment, the light scattering region 122 is provided by the polymer dispersed liquid crystal in a state where no voltage is applied continuously to the effective display region 26, and the light incident from the W color LED 30 is transmitted by the light scattering region 122. By sufficiently entering the effective display area 26 after being scattered, luminance unevenness in the effective display area 26 is prevented.

  FIG. 6 is a diagram showing a schematic configuration of another liquid crystal display device 13 according to the present invention.

  The difference between the liquid crystal display device 13 shown in FIG. 6 and the liquid crystal display device 10 shown in FIG. 2 is that two LEDs are used and the shape of the light diffusion region 123 of the liquid crystal panel 43 is different. The W color LED 31 is the same LED as the W color LED 30 described above, and the two LEDs are used in order to obtain higher luminance in the effective display area 26. In this embodiment, the same number is attached | subjected to the structure similar to FIG.

  The seal member 104 in the present embodiment is made of the same material as the liquid crystal display device 10 shown in FIG. 2, and the four sides are formed to have substantially the same thickness (for example, about 0.8 mm). However, the W-color LED 30 side of the seal member 104 has a shape such that each part gradually spreads in a hyperbola from the portion closest to the W-color LEDs 30 and 31 and continues to the effective display area 26. It is curved along the outer shape of the region 123. In other words, the light diffusion region 123 has a substantially trapezoidal shape (Mt. Fuji shape) with the W-color LEDs 30 and 31 side as the top side, the effective region 26 side as the bottom side, and a left and right concave arc shape. Yes.

  Since the light incident on the liquid crystal panel 43 from each of the W color LEDs 30 and 31 is sufficiently diffused by the light diffusion region 123 of the polymer dispersed liquid crystal provided on the W color LED side inside the seal member 104, The luminance corresponding to the regions 6 and 8 in FIG. 1 does not decrease in luminance, and excessive luminance concentration does not occur in the portion corresponding to the region 7 in FIG. Unevenness does not occur. Therefore, in the present embodiment, it is possible to efficiently use the light emitted from the W color LEDs 30 and 31.

  As described above, in this embodiment, the light scattering region 123 is provided by the polymer dispersed liquid crystal in a state where no voltage is applied continuously to the effective display region 26, and the light incident from the W LEDs 30 and 31 is used as the light scattering region. After being sufficiently scattered by 123, the incident light enters the effective display area 26, thereby preventing uneven brightness in the effective display area 26.

  FIG. 7 is a diagram showing a schematic configuration of another liquid crystal display device 14 according to the present invention.

  The difference between the liquid crystal display device 14 shown in FIG. 7 and the liquid crystal display device 10 shown in FIG. 2 is that two LEDs are used and that two light diffusion regions are provided on the left and right sides of the liquid crystal panel 44. . The W color LED 31 is the same LED as the W color LED 30 described above, and the two LEDs are arranged on the left and right sides in order to obtain higher luminance in the effective display area 26. In this embodiment, the same number is attached | subjected to the structure similar to FIG.

  The sealing member 105 in the present embodiment is made of the same material as the liquid crystal display device 10 shown in FIG. 2, and the four sides are formed to have substantially the same thickness (for example, about 0.8 mm). However, the W-color LEDs 30 and 31 side of the seal member 105 has a shape that gradually expands in a quadratic curve from the portion closest to the W-color LEDs 30 and 31, respectively, and continues to the effective display area 26. The light diffusing regions 124 and 125 are curved along the outer shape. In other words, the light diffusion regions 124 and 125 have a semi-cylindrical shape with the W LEDs 30 and 31 side as the apex and the effective region 26 side as the base.

  Light incident on the liquid crystal panel 44 from each of the W color LEDs 30 and 31 is sufficiently transmitted by the light diffusion regions 124 and 125 of polymer dispersed liquid crystal provided on the W color LED 30 and 31 side inside the seal member 105, respectively. Since it diffuses widely, there is no decrease in luminance in the portion corresponding to the regions 6 and 8 in FIG. 1, and excessive concentration of luminance does not occur in the portion corresponding to the region 7 in FIG. Luminance unevenness does not occur in the entire region 26. Furthermore, since light enters from the left and right of the effective display area 26, the luminance does not decrease on the far side away from the W color LED in the effective display area 26. Therefore, in the present embodiment, it is possible to efficiently use the light emitted from the W color LEDs 30 and 31.

  As described above, in this embodiment, the light scattering regions 124 and 125 are provided by the polymer dispersed liquid crystal in a state in which no voltage is applied to the left and right continuously to the effective display region 26, and the light incident from the W LEDs 30 and 31. Is sufficiently scattered by the light scattering regions 124 and 125 and then incident on the effective display region 26, thereby preventing uneven brightness in the effective display region 26.

  FIG. 8 is a diagram showing a schematic configuration of another liquid crystal display device 15 according to the present invention.

  The difference between the liquid crystal display device 15 shown in FIG. 8 and the liquid crystal display device 10 shown in FIG. 2 is that two LEDs are used and two light diffusion regions are provided on the left and right sides of the liquid crystal panel 45. . The W color LED 31 is the same LED as the W color LED 30 described above, and the two LEDs are arranged on the left and right sides in order to obtain higher luminance in the effective display area 26. In this embodiment, the same number is attached | subjected to the structure similar to FIG.

  The seal member 106 in the present embodiment is made of the same material as the liquid crystal display device 10 shown in FIG. 2, and the four sides are formed to have substantially the same thickness (for example, about 0.8 mm). However, the W-color LEDs 30 and 31 side of the seal member 106 has a shape such that each portion gradually expands in a hyperbola from the portion closest to the W-color LEDs 30 and 31 and continues to the effective display area 26. Curved along the outer shape of the light diffusion regions 126 and 127. In other words, the light diffusion regions 126 and 127 have a substantially trapezoidal shape (Mt. Fuji shape) in which the W-color LEDs 30 and 31 are on the top, the effective region 26 is on the bottom, and the left and right are arcuate. .

  Light incident on the liquid crystal panel 45 from each of the W LEDs 30 and 31 is sufficiently transmitted by the light diffusion regions 126 and 127 of polymer dispersed liquid crystal provided on the W LEDs 30 and 31 side inside the seal member 106, respectively. Since it diffuses widely, there is no decrease in luminance in the portion corresponding to the regions 6 and 8 in FIG. 1, and excessive concentration of luminance does not occur in the portion corresponding to the region 7 in FIG. Luminance unevenness does not occur in the entire region 26. Furthermore, since light enters from the left and right of the effective display area 26, the luminance does not decrease on the far side away from the W color LED in the effective display area 26. Therefore, in the present embodiment, it is possible to efficiently use the light emitted from the W color LEDs 30 and 31.

  As described above, in this embodiment, the light scattering regions 126 and 127 are provided by the polymer dispersed liquid crystal in a state in which no voltage is applied continuously to the effective display region 26, and light incident from the W color LEDs 30 and 31 is emitted as light. Luminance unevenness in the effective display area 26 is prevented by entering the effective display area 26 after being sufficiently scattered by the scattering areas 126 and 127.

  FIG. 9 is a diagram showing a schematic configuration of another liquid crystal display device 16 according to the present invention.

  The difference between the liquid crystal display device 16 shown in FIG. 9 and the liquid crystal display device 10 shown in FIG. 2 is that the shape of the light diffusion region 128 provided in the liquid crystal panel 46 is different. In this embodiment, the same number is attached | subjected to the structure similar to FIG.

  The seal member 107 in this embodiment is made of the same material as that of the liquid crystal display device 10 shown in FIG. 2, and the four sides are formed to have substantially the same thickness (for example, about 0.8 mm). However, the W-color LED 30 side of the seal member 107 was formed in a substantially elliptical shape.

  The light incident on the liquid crystal panel 46 from the W color LED 30 is diffused sufficiently wide by the light diffusion region 128 of the polymer dispersed liquid crystal 23 provided on the W color LED 30 side inside the seal member 107. The luminance corresponding to the regions 6 and 8 does not decrease, and excessive luminance concentration does not occur in the region corresponding to the region 7 in FIG. There is nothing. Therefore, in the present embodiment, it is possible to efficiently use the light emitted from the W color LED 30.

  As described above, in this embodiment, the light scattering region 128 is provided by the polymer dispersed liquid crystal in a state where no voltage is applied continuously to the effective display region 26, and the light incident from the W color LED 30 is transmitted by the light scattering region 128. By sufficiently entering the effective display area 26 after being scattered, luminance unevenness in the effective display area 26 is prevented.

  FIG. 10 is a diagram showing a schematic configuration of another liquid crystal display device 17 according to the present invention.

  The difference between the liquid crystal display device 17 shown in FIG. 10 and the liquid crystal display device 10 shown in FIG. 2 is that the shape of the light diffusion region 129 provided in the liquid crystal panel 47 is different. In this embodiment, the same number is attached | subjected to the structure similar to FIG.

  The seal member 108 in this embodiment is made of the same material as the liquid crystal display device 10 shown in FIG. 2, and the four sides are formed to have substantially the same thickness (for example, about 0.8 mm). However, the W-color LED 30 side of the seal member 108 is configured in a substantially rectangular shape.

  The light incident on the liquid crystal panel 47 from the W color LED 30 is diffused sufficiently wide by the light diffusion region 129 of the polymer dispersed liquid crystal 23 provided on the W color LED 30 side inside the seal member 108. The luminance corresponding to the regions 6 and 8 does not decrease, and excessive luminance concentration does not occur in the region corresponding to the region 7 in FIG. There is nothing. Therefore, in the present embodiment, it is possible to efficiently use the light emitted from the W color LED 30.

  As described above, in the present embodiment, the light scattering region 129 is provided by the polymer dispersed liquid crystal 23 in a state where no voltage is applied continuously to the effective display region 26, and the light incident from the W color LED 30 is converted into the light scattering region 129. After being sufficiently scattered by the incident light, it is incident on the effective display area 26, thereby preventing uneven brightness in the effective display area 26.

  The light scattering regions 120 to 129 have been described with reference to FIGS. 2, 3, and 5 to 10, but the shape of the light scattering regions is an example and is not limited thereto. Therefore, an optimal shape can be selected according to the light amount distribution of the W color LED 30 and / or the W color LED 31 to be used and the shape and size of the effective display area 26.

It is a figure which shows schematic structure of the conventional liquid crystal display device. 1 is a diagram showing a schematic configuration of a liquid crystal display device 10 according to the present invention. It is a figure which shows schematic structure of the other liquid crystal display device 11 which concerns on this invention. It is a figure which shows an example of the light quantity distribution of LED. It is a figure which shows schematic structure of the other liquid crystal display device 12 which concerns on this invention. It is a figure which shows schematic structure of the other liquid crystal display device 13 which concerns on this invention. It is a figure which shows schematic structure of the other liquid crystal display device 14 which concerns on this invention. It is a figure which shows schematic structure of the other liquid crystal display device 15 which concerns on this invention. It is a figure which shows schematic structure of the other liquid crystal display device 16 which concerns on this invention. It is a figure which shows schematic structure of the other liquid crystal display device 17 which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10-17 Liquid crystal display device 21, 22 A pair of glass substrate 23 Polymer dispersion type liquid crystal 26 Effective display area 30, 31 W color LED
40 to 47 Liquid crystal panel 100, 102 to 107 Seal member 120 to 129 Light diffusion region

Claims (6)

A liquid crystal display device,
A liquid crystal panel having an effective display region for displaying information and a light diffusion region continuous with the effective display region, and a polymer-dispersed liquid crystal sandwiched between a pair of substrates;
A sealing member disposed around the polymer-dispersed liquid crystal to seal the polymer-dispersed liquid crystal so as to obtain the effective display region and the light diffusion region between the pair of substrates;
A light source for irradiating light from the side surface of the liquid crystal panel through the polymer dispersed liquid crystal sealed in the light diffusion region;
The light diffusion region has a shape that gradually widens from the light source side toward the effective display region side, depending on the shape of the sealing material .
A liquid crystal display device characterized by the above.   2. The liquid crystal display device according to claim 1, wherein the light diffusion region has a kamaboko shape with the light source side as a vertex and the effective display region side as a base. 3.   The liquid crystal display device according to claim 1, wherein the light diffusion region has a substantially trapezoidal shape with the light source side as a top side and the effective display region side as a bottom side. The light source includes a plurality of LEDs,
The liquid crystal display device according to claim 1, wherein the liquid crystal panel has a plurality of light diffusion regions corresponding to the plurality of LEDs.   The liquid crystal display device according to claim 4, wherein the plurality of LEDs are arranged at positions corresponding to one side surface of the effective display area.   The liquid crystal display device according to claim 5, wherein the plurality of LEDs are respectively arranged at positions corresponding to a plurality of side surfaces of the effective display area.

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