Exemplary embodiments of the invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements.
Hereinafter, a polarizing plate, a liquid crystal device, and an electronic apparatus according to exemplary embodiments of the present invention will be described with reference to the accompanying drawings.
First, a polarizing plate according to an exemplary embodiment of the invention will be described with reference to
As shown in
The support substrate 201 is made of sapphire or crystal. The support substrate 201 prevents application of an external stress to the polarizing film 204 ands as described later, does not disturb light to be polarized by the polarizing film 204 or light polarized by the polarizing films 204.
The polarizing film 204 is an organic film such as one formed of PVA and is formed in the shape of a film. The polarizing film 204 emits light, which has been incident to the polarizing film 2045 as straight polarized light. The second protection layer 203, for example, is made of an optical material such as a transparent film including TAC having a second optical axis 153 formed by being stretched in a predetermined direction, and a second optical axis 153 is disposed to be aligned with a transmission axis of the polarizing film 204.
The first protection layer 205 has only a first optical axis 155 that is formed by being stretched in a predetermined direction. The first protection layer 205 is bonded to one face of the polarizing film 204 such that the first optical axis 155 is aligned with a transmission axis 154 of the polarizing film 204. The polarizing film 204 and the first protection layer 205, for example, are bonded to each other with an adhesive agent (not shown) such as an adhesive material whose retardation value is substantially negligible.
When the polarizing plate 200 is disposed on a light emitting side, flow which light modulated by the liquid crystal layer is emitted, relative to the liquid crystal layer, the first protection layer 205 is located on the liquid crystal layer side relative to the polarizing filmy 204.
In this case, since the first optical axis 155 is aligned with the transmission axis 154 of the polarizing film 204, modulated light incident to the first protection layer 205 directly transmits through the first protection layer 205 without being modulated by the first protection layer 205. Thus, since there is no unintended light absorption in the polarizing film 204, to be more specific, light having an amplitude component other than that of the light modulated by the liquid crystal layer is not absorbed by the polarizing film 204, luminance of the liquid crystal device does not decrease unnecessarily. Furthermore, deterioration of quality of the polarizing film 204 can be reduced, whereby durability of the polarizing plate 200 can be improved.
When the polarizing plate 200, for example, is disposed on the light incident side of the liquid crystal layer and the first protection layer 205 is disposed on the liquid crystal layer side relative to the polarizing film 204, light polarized by the polarizing film 204 is incident to the first protection layer 205. Since the first optical axis 155 is aligned with the transmission axis 154 of the polarizing film 204, a phase of the light polarized by the polarizing film 204 is not disturbed in the first protection layer 205. In other words, the straight polarized light emitted from the polarizing film 204 directly transmits through the first protection layer 205 to be emitted to the liquid crystal layer, and light modulation is performed for the straight polarized light polarized by the polarizing film 204 by the liquid crystal layer. Especially when the polarizing plate 200 is used in a liquid crystal panel having a liquid crystal layer including liquid crystals driven in a VA mode, a phase of light is not disturbed in a stage prior to a light modulation operation that is performed on the basis of birefringence of liquid crystal molecules. Accordingly, there is no medium, which causes a phase difference, interposed between the polarizing film and the liquid crystal layer, thereby, for example, there is no case where the transmittance for a black color changes when black is displayed, and thus, it is possible to increase the contrast level of a display image.
The second protection layer 203 has a second optical axis 153 only. Furthermore, the second protection layer 203 is bonded to the other side of the polarizing film 204 such that the second optical axis 153 is aligned with the transmission axis 154 of the polarizing film 204. Accordingly, the second protection layer does not have an effect on light polarization due to the polarizing film 204 and can support the polarizing film 204. In addition, since the optical axis 151 of the support substrate 201 is aligned with the second optical axis 153, the support substrate 201 does not have an effect on the light polarization due to the polarizing film 204 like the second protection layer 203.
As described above, by using the polarizing plate 200, it is possible to prevent deterioration of the polarizing plate 200 and improve display quality of an image displayed by a liquid crystal device having the polarizing plate 200, to be more specific, a contrast level of the image.
Hereinafter, modified examples of a polarizing plate according to an exemplary embodiment of the invention will be described with reference to
As shown in
In the polarizing plate 300, since a portion corresponding to the display area of the polarizing film 204 does not come into a direct contact with a sealing member that is an adhesive layer, stress is not applied to the display area of the polarizing film 204, whereby deformation of the polarizing film 204 can be prevented.
As shown in
Hereinafter, a liquid crystal device according to an exemplary embodiment of the invention will be described with reference to
The liquid crystal device 1 includes a TFT array substrate 10, an opposing substrate 20, a liquid crystal layer 50, and polarizing plates 200A and 200B.
The TFT array substrate 10, for example, is formed of a crystal substrate, a glass substrate, a silicon substrate, or the like. The opposing substrate 20, for example, is formed of a crystal substrate, a glass substrate, or the like. The TFT array substrate 10 and the opposing substrate 20 are bonded to each other with a sealing member 52 provided in a sealing area 52a around an image display area 10a that is a display area formed by arrangement of a plurality of pixels. A liquid crystal layer 50 that is driven in a VA mode is sealed between the TFT array substrate 10 and the opposing substrate 20 by the sealing member 52 and a liquid crystal sealing portion 156. In addition, a liquid crystal supply port 160 is sealed by the liquid crystal sealing portion 156 such that liquid crystal supplied through the liquid crystal supply port 160 does not leak.
As shown in
On the TFT array substrate 10, wire for electrically connecting an, external circuit connecting terminal 102 and a data line driving circuit 101, a scan line driving circuit 104, upper and lower conduction terminals 106 or the like to each other is formed.
As shown in
Although not shown in the figure, a test circuit, a test pattern, or the like which are used for testing the quality or detecting defects of the liquid crystal device during a manufacturing process thereof or after the manufacturing process may be formed on the TFT array substrate 10, in addition to the data driving circuit 101 and the scan line driving circuit 104.
Hereinafter, relationship of relative directions among optical axes of protection layers included in the polarizing plates 200A and 200B, the transmission axis of the polarizing film, and the like will be described with reference to
As shown in
The polarizing plates 200A and 200B are disposed in a cross-Nicole arrangement, so that a transmission axis 154A of the polarizing film 204A and a transmission axis 154B of the polarizing film 204B are orthogonal to each other. The liquid crystal layer 50 is driven in a VA mode. In other words, the liquid crystal layer 50 has vertically aligned liquid crystal molecules. Accordingly, the liquid crystal device 1 displays an image in a normally-black mode in which black is displayed in the image display area 10a in a case where the liquid crystal device 1 is not driven.
The first protection layer 205B has only a first optical axis 155B that is formed by stretching the first protection layer 205B in a predetermined direction. The first protection layer 205B is disposed on one side of the polarizing film 204B facing the liquid crystal layer 50, so that the first optical axis 155B is aligned with the transmission axis 154B of the polarizing film 204B.
When the liquid crystal device 1 is operated, modulated light emitted to the first protection layer 205B from the liquid crystal layer 50 is transmitted through the first protection layer 205B without disturbing the phase thereof. Thus, the modulated light is detected as the straight polarized light. Accordingly, the transmittance in the cross-Nicole arrangement can be lowered, whereby black with a low luminance level can be acquired. Furthermore, decrease in brightness of display can be prevented. In addition, when the liquid crystal device 1 is operated, increase in temperature of the polarizing film 204B due to heat energy of superfluous light absorbed by the polarizing film 204B can be prevented, whereby the occurrence of distortion or deterioration of the polarizing film 204B due to heat of the polarizing film 204B can be prevented.
The second protection layer 203B has only a second optical axis 153B. The second protection layer 203B is disposed on a side of the polarizing film 204B opposite the liquid crystal layer 503 such that the second optical axis 153B is aligned with the transmission axis 154B of the polarizing film 204B. In addition, the first support substrate 201B is disposed on a side opposite the first protection layer 205B relative to the second protection layer 203B such that an optical axis 151B of the first support substrate 201B is aligned with the first optical axis 155B, the transmission axis 154B, and the second optical axis 153B. Accordingly, light transmitted though the polarizing film 204B is directly emitted without the phase thereof being changed.
The third protection layer 205A has only a third optical axis 155A extending in a predetermined direction. The third protection layer 205A is disposed on a liquid crystal 50 side of the polarizing film 204A such that the third optical axis 155A is aligned with the transmission axis 154A of the polarizing film 204A.
Through the third protection layer 205A, straight polarized light emitted from the polarizing film 204A is directly emitted to the liquid crystal layer 50. Thus, modulation of light performed by the liquid crystal layer 50 is designed on the basis of straight polarized light. When the polarizing plate 200A is used, for example, in a liquid crystal panel having a liquid crystal layer including liquid crystal molecules driven in a VA mode, a phase of light in a stage prior to the performance of light modulation on the basis of birefringence of the liquid crystal molecules is not disturbed and it is possible to increase the contrast level of an image displayed by the liquid crystal device 1. In other words, a phase difference of light due to a retardation value of a protection layer that is interposed between the polarizing film 204A and the liquid crystal layer 50 can be prevented, whereby the decrease in the contrast level due to the phase discrepancy can be suppressed.
The fourth protection layer 203A has only a fourth optical axis 153A. The fourth protection layer 203A is disposed on a side of the polarizing film 204A opposite the liquid crystal layer 50 such that the fourth optical axis 153A is aligned with the transmission axis 154A of the polarizing film 204A. In addition, the second support substrate 201A is disposed on a side opposite the third protection layer 205A relative to the fourth protection layer 203A such that an optical axis 151A of the second support substrate 201A is aligned with the third optical axis 155A, the transmission axis 154A, and the fourth optical axis 153A. Accordingly, light transmitted though the polarizing film 204A is directly emitted to the liquid crystal layer 50 without the phase thereof being changed.
Since a layer having a plurality of optical axes, that is, a medium generating a phase difference is not interposed between the polarizing films 204A and 204B and the liquid crystal layer 50 in the liquid crystal device 1 according to the embodiment as described above, it is possible to increase the contrast level of an image displayed by the liquid crystal device 1, for example, without changing the transmittance of a black color due to the phase difference in a case where black is displayed. In addition, since deterioration of quality of the polarizing, film due to light absorption can be prevented, it is possible to improve the durability of the liquid crystal device.
Furthermore, protection layers of the polarizing plates 200A and 200B included in the liquid crystal device 1, similarly to the above-described polarizing plate 300, may be bonded to each other by a sealing portion which is formed along sides defining edges of the polarizing film. Although the liquid crystal layer has liquid crystal molecules driven in a mode other than the VIA mode, the same advantages as in the V/A mode can be acquired.
Hereinafter, a case where the above-described liquid crystal device is used in a tight valve of a projector that is an example of an electronic apparatus will be described with reference to
Although a case where the liquid crystal panel 2000 used as an optical component and polarizing plates 1000 and 3000 are disposed with a space interposed therebetween is shown in the example of
Hereinafter, a case where the above-described liquid crystal device is used in a projector that is an example of an electronic apparatus will be described with reference to
The liquid crystal panels 1110R, 1110B, and 1110G have structures equivalent to that of the above-described liquid crystal device and are driven in accordance with signals of primary colors of R, G, and B supplied from an image signal processing circuit. The light modulated by the liquid crystal panels is incident to a dichroic prism 1112 from three directions. In the dichroic prism 1112, the light of R and B is refracted by 90 degrees and the light of G progresses straight. Accordingly, a composed image of the primary color light is projected on a screen or the like through a projection lens 1114.
Here, when display images displayed by the liquid crystal panels 1110R, 1110B, and 1110G are considered, the display image displayed by the liquid crystal panel 1110G needs to be inverted to left-to-right/right-to-left side with respect to the display images displayed by the liquid crystal panels 1110R and 1110B.
Furthermore, since light corresponding to primary colors of R, G, and B is incident to the liquid crystal panels 1110R, 1110B, and 1110G by using the dichroic mirror 1108, a color filter is not required. Since the projector 1100 includes the liquid crystal panels 1110R, 1110B, and 1110G, it is possible to display a high-quality image.
Hereinafter, a case where the above-described liquid crystal device is used in a mobile-type personal computer will be described.
Hereinafter, a case where the above-described liquid crystal device is used in a cellular phone will be described.
Furthermore, a liquid crystal device according to an exemplary embodiment of the invention may be used in a television set, a viewfinder-type or monitor direct view-type video cassette recorder, a car navigator, a pager, an electronic diary, a calculator, a word processor, a workstation, a video phone, a POS terminal, an apparatus having a touch panel, or the like along with the above-described electronic apparatuses.
The present invention is not limited to the above-described exemplary embodiments, and various changes in form and details may be made appropriately therein without departing from the gist or spirit of the invention which can be conceived from the claims or the whole specification, and a polarizing plate, a liquid crystal device, and an electronic apparatus in which the changes are made belong to the technical scope of the invention.
Furthermore, in the above exemplary embodiments, a structure in which support substrates are used as protection layers and the support substrates are bonded to other support substrates may be used. Even in that case, the polarizing plate exhibits the same advantages as the above-described embodiments by providing the polarizing plate such that a protection layer having an optical axis is disposed on the liquid panel side of the polarizing plate.
Number | Date | Country | Kind |
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2006-242426 | Sep 2006 | JP | national |