JP2006119240A - Electro-optical device and electronic apparatus - Google Patents

Abstract

Provided is an electro-optical device which can form a semiconductor element having transparency and high carrier mobility even when a substrate made of single crystal silicon is used, and has high reliability. To do.
A TFT substrate formed of single crystal silicon, which transmits infrared light having a wavelength longer than the wavelength of light corresponding to the band gap energy of the single crystal silicon, and on which a semiconductor element is formed, and the TFT substrate And infrared visible wavelength conversion glass 140 that converts the infrared light disposed on the infrared light emitting side to visible light, and performs image display using the visible light. .
[Selection] Figure 2

Description

  The present invention relates to an electro-optical device using single crystal silicon as a substrate, and an electronic apparatus.

  2. Description of the Related Art As is well known, an electro-optical device, for example, a liquid crystal device, is configured as a liquid crystal panel by enclosing a liquid crystal between two substrates. For example, a thin film transistor (hereinafter referred to as a TFT) is provided on one substrate. ) Etc. and pixel electrodes (ITO: Indium Tin Oxide) are arranged in a matrix, the counter electrode is arranged on the other substrate, and the optical characteristics of the liquid crystal layer sealed between the two substrates is determined according to the image signal. This makes it possible to display images.

  By the way, in a transmissive liquid crystal device including a transflective type, since visible light is used as a backlight, a glass substrate that transmits visible light is generally used as a substrate of a liquid crystal panel.

  In an active matrix liquid crystal device provided with TFTs, it is necessary to form a semiconductor element on a glass substrate of a liquid crystal panel. Although it is known that amorphous silicon or polycrystalline silicon is used as the material of the semiconductor element, the amorphous silicon or polycrystalline silicon has low carrier (electron, hole) mobility per unit time. In the case of a semiconductor element that requires high carrier mobility, such as a driver circuit that drives a pixel electrode, it is difficult to mount it on a substrate.

  Furthermore, it is difficult to mount a circuit with high processing capability such as a CPU or an image processor on the substrate. For this reason, the driver circuit and the like are often constituted by a semiconductor integrated circuit (LSI) using single crystal silicon having high carrier mobility.

  However, particularly in a projection-type liquid crystal display device, miniaturization of pixel elements constituting pixel electrodes is required. Therefore, when a driver circuit or the like is composed of LSI, the LSI and the liquid crystal panel are electrically connected at the pitch of the pixel elements. It is difficult to connect.

  The electrical connection is possible with a direct-view type liquid crystal device with a pitch of about 100 μm, but there is a problem that it becomes difficult when it comes to a projection-type liquid crystal device with a pitch of about 10 μm to 20 μm. Therefore, particularly in a projection type liquid crystal display device, it has been required to mount a function conventionally configured in an LSI on a substrate of a liquid crystal panel. Similar demands have also been made for direct-view liquid crystal display devices.

In view of such circumstances, for example, in Non-Patent Document 1, the functions of a driver circuit or the like that have been entrusted to LSIs in the past are integrated on a substrate composed of continuous grain boundary crystal silicon (CG) with high carrier mobility. As a result, a polycrystalline silicon process for semiconductor devices with higher carrier mobility than the conventional one has been disclosed, and the polycrystalline silicon process enables the mounting of functions such as driver circuits on the substrate of a liquid crystal panel. A liquid crystal panel for a high performance projection type liquid crystal display device has been disclosed.
Sharp Technology No. 85, April 2003 "CPU development on a glass substrate using CG Silicon TFT"

  By the way, although the mobility of the carrier on the board | substrate comprised by the continuous grain boundary crystal silicon (CG) disclosed by the nonpatent literature 1 is higher than a polycrystal, it is low according to the single crystal silicon which comprises LSI.

  Therefore, if a substrate made of single crystal silicon can be used as the substrate constituting the liquid crystal panel, the carrier mobility becomes the same as the LSI mobility, so that the performance of the liquid crystal device can be improved. it can.

  However, since single crystal silicon does not have transparency to visible light (wavelength: about 400 nm to 800 nm), it cannot be used for a substrate constituting a liquid crystal panel that requires transparency.

  The present invention has been made paying attention to the above circumstances, and the object thereof is to provide a semiconductor element having transparency even when using a substrate made of single crystal silicon and having high carrier mobility on the substrate. An object of the present invention is to provide an electro-optical device and an electronic apparatus which can be formed and have high reliability.

  To achieve the above object, an electro-optical device according to the present invention is formed of single crystal silicon, transmits light having a wavelength longer than the wavelength of light corresponding to the band gap energy of the single crystal silicon, and forms a semiconductor element. And an infrared visible wavelength conversion means for converting the infrared light disposed on the infrared light emission side of the substrate into visible light, and performing image display with the visible light. It is characterized by that.

  According to the electro-optical device of the present invention, infrared light having a wavelength longer than the wavelength of light corresponding to the band gap energy of the single crystal silicon that has passed through the single crystal silicon is infrared light disposed on the emission side of the substrate. Since it is converted into visible light by an infrared visible wavelength converting means for converting light into visible light, single crystal silicon having a high carrier mobility per unit time can be used as a substrate of an electro-optical device. Since the display controller driver controller and image processor, etc., that were in charge of the device can be formed on the substrate of the electro-optical device, mechanical connection between the devices becomes unnecessary, improving the reliability of the electro-optical device. It has the effect that it can be made.

  Further, since the photoexcitation current does not flow in the pn junction portion of the transistor on the substrate of the electro-optical device, and the light transmitted through the substrate is infrared light, a light shielding film is formed on the upper layer and the lower layer of the pn junction portion. Since it is not necessary, the aperture ratio of the substrate of the electro-optical device can be improved.

  Further, the display device includes an element substrate having a plurality of switching elements and pixels formed in a display region, and a counter substrate disposed to face the element substrate, wherein the substrate is the element substrate or the counter substrate. And Furthermore, it is characterized by having transparency or semi-transparency.

  According to the electro-optical device of the present invention, the infrared light that has passed through the single crystal silicon is arranged on the emission side of the element substrate or the counter substrate, and the infrared visible wavelength conversion means that converts the infrared light into visible light. Can be used for the element substrate or counter substrate of the electro-optical device because the carrier mobility per unit time is high, and the driver controller for the display element previously handled by LSI In addition, since the image processor and the like can be formed on the element substrate or the counter substrate of the electro-optical device, mechanical connection between the devices is not necessary, and the reliability of the electro-optical device can be improved. Has an effect.

  In addition, since the photoexcitation current does not flow in the pn junction portion of the transistor on the element substrate of the electro-optical device and the light transmitted through the element substrate is infrared light, a light shielding film is provided on the upper and lower layers of the pn junction portion. Since it is not necessary to form it, the aperture ratio of the element substrate of the electro-optical device can be improved.

  Furthermore, since the transparent electrode (ITO) formed on the element substrate can be changed to a silicon-based material such as polycrystalline silicon, patterning is facilitated and the manufacturing process is facilitated.

  In addition, the manufacturing cost can be reduced by using an electrode made of a silicon-based material such as polycrystalline silicon instead of expensive ITO.

  In the electro-optical device in which a pair of substrates are arranged to face each other, the first substrate of the pair of substrates is formed of single crystal silicon, and the band gap of the single crystal silicon constituting the first substrate Infrared light having a wavelength longer than the wavelength of light corresponding to energy is transmitted, the semiconductor element is formed, and a second substrate of the pair of substrates is disposed to face the first substrate, An electro-optical device, comprising: an infrared-visible wavelength converting unit that converts the infrared light incident from the first substrate side into visible light, and performing image display with the visible light. Further, the first substrate is an element substrate in which a plurality of switching elements and pixels are formed in a display region.

  According to the electro-optical device of the present invention, the infrared light transmitted through the single crystal silicon is converted into visible light by an infrared-visible wavelength conversion unit that converts infrared light into visible light, which is disposed on the emission side of the element substrate. Therefore, single crystal silicon having a high carrier mobility per unit time can be used for the element substrate of the electro-optical device, and the driver controller and the image processing processor of the display element previously handled by the LSI can be used. Since it can be formed on the element substrate of the electro-optical device, mechanical connection between devices is unnecessary, and the reliability of the electro-optical device can be improved.

  In addition, since the photoexcitation current does not flow in the pn junction portion of the transistor on the element substrate of the electro-optical device and the light transmitted through the element substrate is infrared light, a light shielding film is provided on the upper and lower layers of the pn junction portion. Since it is not necessary to form it, the aperture ratio of the element substrate of the electro-optical device can be improved.

  Furthermore, since the transparent electrode (ITO) formed on the element substrate can be changed to a silicon-based material such as polycrystalline silicon, patterning is facilitated and the manufacturing process is facilitated.

  In addition, the manufacturing cost can be reduced by using an electrode made of a silicon-based material such as polycrystalline silicon instead of expensive ITO.

  Further, the infrared visible wavelength conversion means is a material that converts the infrared light into visible light having a wavelength band of red, green, or blue.

  According to the electro-optical device of the present invention, it is possible to perform monocolor display using the electro-optical device without providing a color filter on the substrate.

  Further, the infrared visible wavelength conversion means includes a material that converts the infrared light into visible light in each red wavelength band, a material that converts visible light in the green wavelength band, and a visible light in the blue wavelength band, respectively. It is characterized by comprising a material that converts light.

  According to the electro-optical device of the present invention, it is possible to perform color display using the electro-optical device without providing a color filter on the substrate.

  Further, the wavelength conversion material is provided corresponding to the pixel.

  According to the electro-optical device of the present invention, it is possible to reliably convert infrared light into visible light and perform color display using the electro-optical device.

  An electronic apparatus according to the present invention includes an electro-optical device according to any one of claims 1 to 8 and infrared light having a wavelength longer than a wavelength of light corresponding to a band gap energy of the single crystal silicon constituting the substrate. And infrared light generating means for generating the light.

  According to the electronic device of the present invention, the reliability is improved, the aperture ratio of the substrate is improved, the manufacturing process is easy, the manufacturing cost can be reduced, and a monocolor or color can be provided without providing a color filter. There is an effect that it is possible to provide an electronic apparatus in which an electro-optical device capable of display is provided.

  The electro-optical device includes a transmissive or reflective screen disposed on the emission side of the electro-optical device.

  According to the electronic device of the present invention, the reliability is improved, the aperture ratio of the substrate is improved, the manufacturing process is easy, the manufacturing cost can be reduced, and a monocolor or color can be provided without providing a color filter. There is an effect that it is possible to provide an electronic apparatus which is a projection type display device provided with an electro-optical device capable of displaying.

  An electronic apparatus according to the present invention includes a transmissive or semi-transmissive electro-optical device configured by a substrate that transmits infrared light formed of single crystal silicon, and the infrared light incident side of the electro-optical device. An infrared light generating means for generating infrared light having a wavelength longer than the wavelength of light corresponding to the band gap energy of the single crystal silicon constituting the element substrate and the counter substrate; and the electro-optical device Infrared-visible wavelength converting means for converting the infrared light disposed on the infrared light emitting side to visible light, and a transmissive or reflective screen disposed on the emitting side of the electro-optical device The infrared visible wavelength converting means is arranged on the screen.

  According to the electronic apparatus of the present invention, the reliability is improved, the aperture ratio of the substrate is improved, the manufacturing process is easy, and the cost is reduced without providing the infrared-visible wavelength conversion means in the electro-optical device. An electronic device which is a projection type display device that can be provided can be provided.

  Further, the infrared visible wavelength conversion means is a material that converts the infrared light into visible light having a wavelength band of red, green, or blue.

  According to the electronic apparatus of the present invention, it is possible to perform monocolor display without providing a color filter or infrared visible wavelength conversion means in the electro-optical device, and perform color display by using three electro-optical devices. It is possible to provide an electronic device that can be used.

  Further, the infrared visible wavelength conversion means includes a material that converts the infrared light into visible light in each red wavelength band, a material that converts visible light in the green wavelength band, and a visible light in the blue wavelength band, respectively. It is characterized by comprising a material that converts light.

  According to the electronic apparatus of the present invention, there is an effect that it is possible to provide an electronic apparatus capable of performing color display without providing a color filter or an infrared-visible wavelength conversion unit in the electro-optical device.

  Embodiments of the present invention will be described below with reference to the drawings. In the present embodiment, the electro-optical device is a transmissive electro-optical device, for example, an element substrate (hereinafter referred to as a TFT substrate) which is a first substrate and a second substrate. A liquid crystal device in which an electro-optical material is sandwiched between a TFT substrate (hereinafter referred to as a counter substrate) facing the TFT substrate will be described as an example.

(First embodiment)
FIG. 1 is a plan view of a liquid crystal device showing a first embodiment of the present invention, and FIG. 2 is a sectional view taken along line II-II in FIG.

  As shown in the figure, the liquid crystal device 1 is a substrate having a thickness of 50 to 100 microns made of single crystal silicon that transmits infrared light having a wavelength longer than the wavelength of light corresponding to the band gap energy of single crystal silicon. A liquid crystal 50, which is an electro-optical material, is sealed between a TFT substrate 10 using a glass substrate and a counter substrate 20 using, for example, a glass substrate or a quartz substrate. The TFT substrate 10 and the counter substrate 20 that are arranged to face each other are bonded together by a sealing material 52.

  The wavelength of the infrared light transmitted through the single crystal silicon constituting the TFT substrate 10 is a wavelength longer than the wavelength λ = 1.24 / 1.1 eV (bandgap energy of silicon) = 1100 nm. Are known.

  A pixel electrode (ITO) 9a that constitutes a pixel and a TFT (not shown) connected to the pixel electrode 9a are provided on the surface 10a that is the opposite surface of the TFT substrate 10 and is on the emission side of the transmitted infrared light. Are arranged in a matrix. In addition, the color filter 28 that converts light emitted from the liquid crystal device 1 into red, which is the three primary colors of the light, green, or blue, over the entire surface 20a, which is the opposing surface of the counter substrate 20, is provided. Any one of them is provided, and a counter electrode (ITO) 21 is provided on the entire surface of the color filter 28.

  On the pixel electrode 9 a of the TFT substrate 10, an infrared visible wavelength conversion glass 140 which is an infrared visible wavelength conversion means described later is provided. In addition, an alignment film 16 that has been subjected to a rubbing process is provided on the infrared-visible wavelength conversion glass 140. On the other hand, an alignment film 22 subjected to a rubbing process is also provided on the counter electrode 21 formed over the entire surface of the counter substrate 20. The alignment films 16 and 22 are made of a transparent organic film such as a polyimide film, for example.

  Furthermore, a polarizing plate 111 is provided on the back surface 10a of the TFT substrate 10 on the surface on the infrared light incident side, and a polarizing plate 121 is also provided on the back surface of the front surface 20a of the counter substrate 20. Is provided.

  A light shielding film 53 is provided on the counter substrate 20 as a frame for partitioning the display area 40. Further, a sealing material 52 that encloses liquid crystal is formed between the TFT substrate 10 and the counter substrate 20 in a region outside the light shielding film 53. The sealing material 52 is disposed so as to substantially match the contour shape of the counter substrate 20, and fixes the TFT substrate 10 and the counter substrate 20 to each other.

  The sealing material 52 is missing in a part of one side of the TFT substrate 10, and as a result, a liquid crystal injection port 108 for injecting the liquid crystal 50 is formed. The liquid crystal 50 is injected from the liquid crystal injection port 108 into the gap between the bonded TFT substrate 10 and the counter substrate 20. After the liquid crystal 50 is injected, the liquid crystal injection port 108 is sealed with a sealing material 109.

  An image signal is supplied to a data line (not shown) of the TFT substrate 10 at a predetermined timing in a region outside the sealing material 52, and the data line driving circuit 101 that drives the data line and an external for connection to an external circuit Connection terminals 102 are provided along one side of the TFT substrate 10.

  A scanning line driving circuit 104 that drives the gate electrode by supplying scanning signals to scanning lines and gate electrodes (not shown) of the TFT substrate 10 at a predetermined timing is provided along two sides adjacent to the one side. .

  The scanning line driving circuit 104 is formed on the TFT substrate 10 at a position facing the light shielding film 53 inside the sealing material 52. Further, on the TFT substrate 10, wiring 105 for connecting the data line driving circuit 101, the scanning line driving circuit 104, the external connection terminal 102, and the vertical conduction terminal 107 is provided to face the three sides of the light shielding film 53. .

  The vertical conduction terminals 107 are formed on the four TFT substrates 10 at the corners of the sealing material 52. Between the TFT substrate 10 and the counter substrate 20, a vertical conductive material 106 having a lower end in contact with the vertical conduction terminal 107 and an upper end in contact with the counter electrode 21 is provided. And the counter substrate 20 are electrically connected.

  Here, the infrared visible wavelength conversion glass 140 formed on the pixel electrode 9a of the TFT substrate 10 will be described. The infrared-visible wavelength conversion glass 140 converts infrared light having a wavelength longer than 1100 nm, which is transmitted through single crystal silicon, into visible light. For example, Japanese Patent Application Laid-Open No. 9-86958 uses an up-conversion mechanism. Then, a glass material that converts infrared light having a wavelength of 1500 nm into visible light in a green wavelength band of wavelengths 510 to 560 nm or a blue wavelength band of wavelengths 410 nm to 450 nm among the three primary colors of light is disclosed. Has been.

  The up-conversion mechanism means that even in the case of excitation light with a small one-photon energy such as infrared light, ions in the up-conversion material (infrared visible wavelength conversion material) absorb many photons. Excited to an energy state, this is a mechanism that emits energy light higher than the excitation light, that is, visible light as a result of transitioning to a lower level or a ground state again.

  Japanese Patent Publication No. 6-29150 discloses a wavelength conversion glass material that converts infrared light having a wavelength of 900 to 1100 nm into visible light in the red wavelength band of wavelength 650 nm among the three primary colors of light. ing.

  In the present embodiment, any one of the wavelength conversion glass materials described above is used for the infrared visible wavelength conversion glass 140. In addition, the wavelength conversion glass material disclosed in JP-A-9-86958 is a method for heating and melting a mixed powder prepared by mixing a predetermined amount of a purified and dried raw material halide in an argon atmosphere or under vacuum. It is shown that a wavelength conversion glass material can be obtained by quenching the melt obtained by quenching, or by pouring the melt melt heated and melted between graphite plates having a parallel interval of about 1 mm to quench the melt. .

  Therefore, in the present embodiment, when the infrared-visible wavelength conversion glass 140 is formed on the pixel electrode 9a of the TFT substrate 10, the above-mentioned mixture heated and melted on the pixel electrode 9a of the TFT substrate 10 in an argon atmosphere. The infrared visible wavelength conversion glass 140 is formed by applying the powder by spin coating and quenching. When formed in this way, the film thickness of the infrared visible wavelength conversion glass 140 is 1 μm to 10 μm. This forming method is suitable when the conversion glass material has high conversion efficiency from infrared light to visible light and low transmittance.

  On the other hand, when the conversion glass material has low conversion efficiency from infrared light to visible light and high transmittance, the mixed powder heated and melted is poured between graphite plates having a parallel interval of about 1 mm and rapidly cooled. After the quenching body, that is, the infrared visible wavelength conversion glass 140 is obtained, the infrared visible wavelength conversion glass 140 is formed on the pixel electrode 9a of the TFT substrate 10 by pasting.

  In addition, in the Japanese Patent Publication No. 6-29150, infrared visible wavelength conversion glass 140R for converting infrared light having a wavelength of 900 to 1100 nm into visible light in a red wavelength band of wavelength 650 nm among the three primary colors of light. In the case of forming on the pixel electrode 9a of the TFT substrate 10, the wavelength of 1100 nm is a boundary wavelength that transmits single crystal silicon, but silicon is also transmitted to some extent even at the boundary wavelength because of indirect transition. Since the transmittance depends on the film thickness of silicon, if the TFT substrate 10 is formed thin, light can be transmitted even at a wavelength of 1100 nm.

  In this way, on the pixel electrode 9a of the TFT substrate 10, infrared visible wavelength for converting infrared light having a wavelength of 1100 nm or more into visible light corresponding to the three primary colors of light, green, blue, and red. Any of the conversion glass is formed.

  Next, the operation of the liquid crystal device 1 configured as described above will be described. FIG. 3 is a cross-sectional view of the liquid crystal device 1 for explaining the operation of the liquid crystal device 1.

  As shown in the figure, when infrared light having a wavelength longer than 1100 nm is incident from the TFT substrate 10 side, which is the incident side of the liquid crystal device 1, by infrared light generating means (not shown), the infrared light is simply transmitted. The TFT substrate 10 made of crystalline silicon is transmitted, and immediately after the transmission, the infrared / visible wavelength conversion glass 140 converts the light into any visible light corresponding to the green, blue, and red wavelength bands.

  The converted visible light passes through the liquid crystal 50 and then becomes visible light of any one of green, blue, and red by the color filter 28, passes through the counter substrate 20, and is the counter substrate 20 that is the emission side of the liquid crystal device 1. It is emitted from. By the infrared visible wavelength conversion glass 140, any visible light corresponding to the wavelength band of green, blue, and red is further passed through the color filter 28, so that the infrared visible wavelength conversion glass 140 can not be adjusted completely. Wavelength range can be cut and color tone can be corrected. When such color tone adjustment is unnecessary, a color filter is unnecessary. Note that the driving operation of the liquid crystal 50 at this time is the same as that in the conventional case using visible light, and thus the description thereof is omitted.

  The liquid crystal device 1 configured as described above is used in an electronic device, for example, a light projection display device, specifically, a projector. 4 is a diagram showing a configuration of a projector in which one liquid crystal device 1 in FIGS. 1 to 3 is arranged, and FIG. 5 is a configuration of a projector in which three liquid crystal devices 1 in FIGS. 1 to 3 are arranged. FIG.

  When one liquid crystal device 1 is used, as shown in FIG. 4, one liquid crystal device 1 is disposed in the projector 1100 as one of RGB light valves. Hereinafter, “liquid crystal device” will be read as “light valve”. At this time, on the pixel electrode 9a of the TFT substrate 10 of the light valve 1, infrared visible wavelength conversion glass 140R that converts infrared light having a wavelength of 900 to 1100 nm into visible light in a red wavelength band of wavelength 650 nm, Alternatively, infrared visible wavelength conversion glass 140G that converts infrared light having a wavelength of 1500 nm to visible light in a green wavelength band of wavelength 510 to 560 nm, or infrared light having a wavelength of 1500 nm is wavelength 410 nm to 450 nm. An infrared-visible wavelength conversion glass 140B that converts visible light in the blue wavelength band is formed.

  Further, the red color filter 28 so that light converted into visible light in the red wavelength band having a wavelength of 650 nm is emitted from the light valve 1 as red on the entire surface 20a of the counter substrate 20 of the light valve 1. The light converted into visible light in the green wavelength band of 510 to 560 nm is converted into visible light in the green color filter 28 or the blue wavelength band of 410 to 450 nm so that it is emitted from the light valve 1 as green. A blue color filter 28 is provided so that the emitted light is emitted from the light valve 1 as blue.

  Further, an infrared light generation unit 1102 that is infrared light generation means for emitting infrared light having a wavelength longer than 1100 nm to the projector 1100 and infrared light emitted from the infrared light generation unit 1102 1 and a screen 1120 for displaying an image projected from the light valve 1 are provided.

  In the projector 1100, when infrared light having a wavelength longer than 1100 nm is emitted from the infrared light generation unit 1102, the infrared light is guided to the light valve 1 by the two dichroic mirrors 1108.

  Then, as shown in FIG. 3, the light component corresponding to one of the three primary colors converted into visible light by the light valve 1 is monotonically applied to the reflective screen 1120 via the projection lens 1114. Projected as a color image.

  When three liquid crystal devices 1 are used, as shown in FIG. 5, for example, three (1R, 1G, 1B) liquid crystal devices 1 are disposed in the projector 1200 as light valves for RGB. At this time, the infrared visible wavelength conversion glass 140R is formed on the pixel electrode 9a of the TFT substrate 10 of the light valve 1R, and the light converted into red visible light on the entire surface 20a of the counter substrate 20. However, a red color filter 28 is provided so as to be emitted from the light valve 1R as red.

  In addition, an infrared visible wavelength conversion glass 140G is formed on the pixel electrode 9a of the TFT substrate 10 of the light valve 1G, and light converted into green visible light is formed on the entire surface 20a of the counter substrate 20. A green color filter 28 is provided so as to be emitted from the light valve 1G as green.

  Further, an infrared-visible wavelength conversion glass 140B is formed on the pixel electrode 9a of the TFT substrate 10 of the light valve 1B, and light converted into blue visible light is formed on the entire surface 20a of the counter substrate 20. A blue color filter 28 is provided so as to be emitted from the light valve 1B as blue.

  In addition, an infrared light generation unit 1102 that emits infrared light having a wavelength longer than 1100 nm is sent to the projector 1200, and infrared light emitted from the infrared light generation unit 1102 is sent to the light valves 1R, 1G, and 1B, respectively. Means for guiding and a screen 1120 for displaying an image synthesized and projected from the light valves 1R, 1G, and 1B are disposed.

  In the projector 1200, when infrared light having a wavelength longer than 1100 nm is emitted from the infrared light generation unit 1102, the light components R corresponding to the three primary colors of RGB are obtained by three mirrors 1106 and two dichroic mirrors 1108. Divided into G and B, they are guided to the light valves 1R, 1G and 1B corresponding to the respective colors.

  At this time, in particular, the B light is guided through a relay lens system 1121 including an incident lens 1122, a relay lens 1123, and an exit lens 1124 in order to prevent light loss due to a long optical path.

  Then, as shown in FIG. 3, the light valves 1R, 1G, and 1B are converted into visible light, and the light components corresponding to the modulated three primary colors are synthesized again by the dichroic prism 1112, and then the projection lens. A color image is projected on the reflective screen 1120 via 1114.

  The liquid crystal device 1 is used in a rear projector that is a light projection display device. FIG. 6 is a diagram illustrating a configuration of a rear projector in which the liquid crystal device 1 of FIGS. 1 to 3 is disposed.

  As shown in the figure, in the rear projector 1300, a projector unit 1302 is disposed at the lower part of the housing 1301, a projection mirror 1303 is disposed on the upper back side, and the reflection direction of the projection mirror 1303 is further increased. A transmissive screen 1304 is provided on the front surface of a certain housing 1301.

  The projector unit 1302 includes a cooling fan 1305 disposed on both lower sides of the housing 1301, and a unit 1200A (FIG. 5) having three (1R, 1G, 1B) liquid crystal devices 1 as RGB light valves. And a main drive unit 1309 for controlling each circuit unit of the projector unit 1302. Note that the configuration of the unit 1200A is the same as that of the projector 1200 shown in FIG.

    As shown in FIG. 3, by the light valves 1R, 1G, and 1B in the projection optical system 1307, infrared light having a wavelength of 1100 nm or more is converted into visible light in each wavelength band, and corresponds to the three primary colors of modulated light. The light components to be combined are again synthesized and then emitted from the projection lens 1307c as indicated by the arrows.

  The projection light 1310 that is visible light emitted from the projection lens 1307 c is reflected by the projection mirror 1303, guided to the screen 1304 side, and transmitted through the screen 1304. A color image of visible light transmitted through the screen 1304 is observed by the observer A. Note that a unit 1100A (see FIG. 4) having one liquid crystal device 1 is provided in the rear projector 1300 to perform monocolor display, which is substantially the same as the above-described configuration.

  As described above, in the liquid crystal device and the electronic apparatus showing the first embodiment of the present invention, infrared light having a wavelength longer than 1100 nm transmitted through the TFT substrate 10 made of single crystal silicon of the liquid crystal device 1 is transmitted. Since it is converted into visible light by the infrared visible wavelength conversion glass 140 disposed on the pixel electrode 9a on the TFT substrate 10, single crystal silicon having high carrier mobility per unit time is used as the TFT of the liquid crystal device 1. Since a driver controller, an image processing processor, and the like of a display element that can be used for the substrate 10 and have been previously handled by the LSI can be formed on the TFT substrate 10 of the liquid crystal device 1, the device-to-device mechanical Connection is unnecessary, and the reliability of the liquid crystal device 1 can be improved.

  Further, since the photoexcitation current does not flow in the pn junction portion of the transistor (TFT) on the TFT substrate 10 of the liquid crystal device 1, and the light transmitted through the TFT substrate 10 is infrared light, the upper layer of the pn junction portion and Since it is not necessary to form a light shielding film (not shown) in the lower layer, the aperture ratio of the substrate of the liquid crystal device 1 can be improved.

  In addition, since the light transmitted through the TFT substrate 10 is infrared light, the pixel electrode (ITO) 9a formed on the TFT substrate 10 can be changed to a silicon material such as polycrystalline silicon, so that patterning is easy. The manufacturing process becomes easy. Further, since the pixel electrode 9a formed on the TFT substrate 10 can be made of an electrode made of a silicon-based material such as polycrystalline silicon instead of expensive ITO in terms of material and manufacturing process, the manufacturing cost can be reduced. .

  Hereinafter, a modification is shown. In the present embodiment, the infrared visible wavelength conversion glass 140 has been shown to be formed on the pixel electrode 9a on the surface 10a which is a surface on the emission side of the TFT substrate 10 made of single crystal silicon. However, the present invention is not limited to this, and the effect similar to that of the present embodiment can be obtained no matter where it is formed after passing through a substrate formed of single crystal silicon.

  For example, as shown in FIG. 7, it may be formed on the back surface of the counter surface 20a of the counter substrate 20 by the method described above. In this case, when infrared light having a wavelength longer than 1100 nm is incident from the TFT substrate 10 side which is the incident side of the liquid crystal device 1, the infrared light is transmitted through the TFT substrate 10 made of single crystal silicon. After passing through the liquid crystal 50, after passing through the counter substrate 20, that is, after completely passing through the liquid crystal device 1, any one of the wavelengths corresponding to the green, blue, and red wavelength bands by the infrared visible wavelength conversion glass 140. And is emitted from the counter substrate 20 on the emission side of the liquid crystal device 1. The example of FIG. 7 is preferably applied when color tone correction using a color filter is not necessary, but a color filter may be formed on the infrared visible wavelength conversion glass 140 as necessary.

  In the example of FIG. 7, the counter substrate 20 can also be formed of single crystal silicon. In this case, a circuit element formed of single crystal silicon used for a power supply circuit, an image processing circuit, or the like can be formed on the counter substrate 20.

  Thus, even if the infrared visible wavelength conversion glass 140 is formed, the same effect as this embodiment can be obtained.

  Further, another modification example will be described below. In the present embodiment, an infrared visible wavelength conversion glass 140 that converts infrared light into visible light in any one of the red, green, and blue wavelength bands among the three primary colors of light is arranged in one liquid crystal device 1. It was shown that it was installed. Therefore, as shown in FIG. 5, when a color image is displayed using the projector 1200, three liquid crystal devices 1 are disposed on the projector 1200 so as to correspond to R, G, and B.

  However, the present invention is not limited to this, and even a single liquid crystal device can display a color image. The color filter 28 is formed in a matrix for R, G, and B on the surface 20a of the counter substrate 20 so as to correspond to each pixel on which the TFT of the TFT substrate 10 is formed. Although it is well known that a color image can be displayed even in such a case, in this embodiment, since infrared light is used, it is only necessary to form the color filter 28 in a matrix for each of R, G, and B. A color image cannot be realized. Therefore, a color image display without using the color filter 28 is realized.

  8 is a cross-sectional view showing a modification of the configuration of the liquid crystal device 1 in FIG. 2, FIG. 9 is a diagram showing the configuration of the infrared-visible wavelength conversion glass in FIG. 8, and FIG. 10 is the infrared-visible in FIG. It is a front view of the opposing board | substrate of FIG. 8 which shows the arrangement | sequence of wavelength conversion glass.

  As shown in FIG. 8, an infrared visible wavelength conversion glass 140 that is an infrared visible wavelength conversion means is formed on the surface 20 a of the counter substrate 20. As shown in FIG. 9, the infrared visible wavelength conversion glass 140 includes an infrared visible wavelength conversion glass 140R, an infrared visible wavelength conversion glass 140G, and an infrared visible wavelength conversion glass 140B.

  Further, as shown in FIG. 10, the infrared visible wavelength conversion glasses 140R, 140G, and 140B are formed on the surface of the counter substrate 20 like a color filter so as to correspond to each pixel on which the TFT of the TFT substrate 10 is formed. 20a is formed in a matrix.

  Note that the infrared visible wavelength conversion glasses 140R, 140G, and 140B are formed on the surface 20a of the counter substrate 20 using an ink jet method or a photoengraving method, as in the color filter forming method.

  In the case of forming by the inkjet method, a predetermined amount of purified and dried raw material halide is prepared in the opening of the light shielding film 53 (BM) of the counter substrate 20 made of chromium (metal) formed by the sputtering method. The mixed powder is heated and melted in an argon atmosphere or under vacuum, and the heated and melted material (wavelength conversion glass material) is injected by an ink jet method and rapidly cooled, whereby infrared visible wavelength conversion glasses 140R, 140G, and 140B are formed in a matrix. To form.

  On the other hand, in the case of producing by photoengraving, a mixed powder prepared by mixing a predetermined amount of purified and dried raw material halide is heated and melted in an argon atmosphere or under vacuum, and the heat-melted one (wavelength conversion glass material) is used. After applying by spin coating and rapidly cooling, the infrared visible wavelength conversion glass 140R, 140G, 140B is formed by patterning in a matrix using a photoengraving process.

  One liquid crystal device 1 formed in this way is disposed in, for example, a projector 1100 as shown in FIG. 4 described above. When any one of the infrared visible wavelength conversion glasses 140R, 140G, and 140B is formed on the liquid crystal device 1, only monocolor display was possible. However, the infrared visible wavelength conversion glasses 140R, 140G, and 140B were provided on the liquid crystal device 1. Is formed in a matrix, color display can be performed on the screen 1120 with one liquid crystal device without using the color filter 28 even if infrared light is used.

  In addition, although the example which does not use the color filter 28 was shown, if the color filter 28 is formed in a matrix so as to correspond to R, G, and B in the liquid crystal device 1 in addition to the above-described configuration, more accurate color tone. Correction can be performed.

(Second Embodiment)
FIG. 11 is a cross-sectional view schematically illustrating the configuration of a liquid crystal device according to a second embodiment of the present invention, FIG. 12 is a diagram illustrating the configuration of a projector in which one liquid crystal device of FIG. 11 is provided, and FIG. FIG. 14 is a diagram showing the configuration of a rear projector in which the liquid crystal device 1 of FIG. 11 is disposed, and FIG. 14 is a front view of a screen showing the arrangement of the infrared-visible wavelength conversion glasses of FIGS.

  The configurations of the liquid crystal device 201, projectors 2100, 2200, and rear projector 2300 of the present embodiment are different from those of the liquid crystal device 1, projectors 1100, 1200, and rear projector 1300 of the first embodiment shown in FIGS. The infrared visible wavelength conversion glass is different from the liquid crystal device in that it is provided on the screen. Therefore, only this difference will be described, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof will be omitted.

  As shown in FIG. 11, the liquid crystal device 201 includes a TFT substrate 210 using a substrate having a thickness of 50 to 100 microns made of single crystal silicon that transmits infrared light, and an infrared ray disposed opposite to the TFT substrate 210. A liquid crystal 50 is sealed between the counter substrate 220 and a substrate having a thickness of 50 to 100 microns made of single crystal silicon that transmits light, thereby forming a panel. The TFT substrate 210 and the counter substrate 220 which are arranged to face each other are bonded together by a sealing material 52.

  In addition, the wavelength of the infrared light which permeate | transmits the said single crystal silicon which comprises the TFT substrate 210 and the opposing board | substrate 220 is wavelength λ = 1.24 / 1.1eV (bandgap energy of silicon) = 1100nm longer wavelength It is known that

  A pixel electrode (ITO) 9a constituting a pixel and a TFT (not shown) connected to the pixel electrode 9a are arranged in a matrix on a surface 210a opposite to the TFT substrate 210 that is an emission side of transmitted infrared light. Is arranged.

  A counter electrode (ITO) 21 is provided on the entire surface 220a, which is the counter surface of the counter substrate 220, at a position corresponding to each pixel on which the TFT of the TFT substrate 210 is formed.

  On the pixel electrode 9a of the TFT substrate 210, an alignment film 16 that has been subjected to a rubbing process is provided. On the other hand, the alignment film 22 subjected to the rubbing process is also provided on the counter electrode 21 formed over the entire surface of the counter substrate 220. The alignment films 16 and 22 are made of a transparent organic film such as a polyimide film, for example.

  Further, a polarizing plate 111 is provided on the back surface 210 a of the TFT substrate 210 on the infrared light incident side, and a polarizing plate 121 is also provided on the back surface of the front surface 220 a of the counter substrate 220. Is provided.

  Since other configurations are the same as those of the liquid crystal device 1 of the first embodiment described above, the description thereof is omitted.

  The thus configured liquid crystal device 201 is used in an electronic apparatus, for example, a light projection display device, specifically, a projector.

  As shown in FIG. 12, one liquid crystal device 201 is disposed as a light valve for RGB in the projector 2100. Hereinafter, “liquid crystal device” is read as “light valve”. Further, on the screen 1120, infrared visible wavelength conversion glass 240R that converts infrared light having a wavelength of 900 to 1100 nm into visible light in a red wavelength band of wavelength 650 nm, or infrared light having a wavelength of 1500 nm. Infrared visible wavelength conversion glass 240G for converting to visible light in the green wavelength band of wavelengths 510 to 560 nm or infrared light having a wavelength of 1500 nm to visible light in the blue wavelength band of wavelengths 410 nm to 450 nm As shown in FIG. 14, the infrared visible wavelength conversion glass 240 </ b> B is formed in a matrix by the above-described method so as to correspond to R, G, and B, respectively.

  The other configuration of the projector 2100 is the same as the configuration of the projector 1100 described above with reference to FIG.

  In the projector 2100, when infrared light having a wavelength longer than 1100 nm is emitted from the infrared light generation unit 1102, the infrared light is guided to the light valve 201 by the two dichroic mirrors 1108.

  Then, the light components corresponding to the three primary colors modulated by the light valve 201 are projected onto the reflective screen 1120 via the projection lens 1114, and then the infrared visible wavelength conversion means on the screen 1120 is infrared. In the visible wavelength conversion glass 240, visible light in the red wavelength band, visible light in the green wavelength band, and visible light in the blue wavelength band are respectively converted, and an image by the visible light is observed by an observer. ing.

  The liquid crystal device 201 is used in a rear projector that is a light projection display device. As shown in FIG. 13, the infrared visible wavelength conversion glass 240R, the infrared visible wavelength conversion glass 240G, or the infrared visible wavelength conversion glass 240B is applied to the screen 1304 of the rear projector 2300 in the manner shown in FIG. As shown, it is formed in a matrix so as to correspond to R, G, and B, respectively.

  In addition, the projector unit 1302 includes a projection optical system 1307 in which a unit 2100A (see FIG. 12) having one liquid crystal device 1 is provided as a light valve for RGB. The configuration of the unit 2100A is the same as that of the projector 2100 shown in FIG.

    The other rear projector 2300 has the same configuration as that of the rear projector 1300 described above with reference to FIG.

  Infrared light 2310 emitted from the projection lens 1307c is reflected by the projection mirror 1303 and guided to the screen 1304 side. Thereafter, in the infrared visible wavelength conversion glass 240 on the screen 1120, visible light in the red wavelength band, The light is converted into visible light in the green wavelength band and visible light 1310 in the blue wavelength band, and the visible light 1310 passes through the screen 1120. The image by visible light 1310 is observed by an observer.

  As described above, in the liquid crystal device 201, the projectors 2100 and 2200, and the rear projector 2300 according to the present embodiment, the infrared visible wavelength conversion glass 240 is provided on the screen and on the matrix.

  Therefore, it is not necessary to form infrared-visible wavelength conversion glass on the liquid crystal device 1, and the manufacturing process of the liquid crystal device 1 is facilitated. Other effects are the same as those of the first embodiment described above.

  Further, the electro-optical device manufactured according to the present invention has been described by taking a transmissive liquid crystal device as an example. However, the present invention is not limited to this, and various types of electric devices having translucency, that is, transflective types are included. Of course, it can be applied to an optical device.

  For example, the configuration of the transflective liquid crystal device 1 when the configuration of FIG. 2 is applied will be described. In this case, examples of the light source of the liquid crystal device 1 include infrared light generating means as an internal light source and visible light incident from the outside.

  First, a transmissive region and a reflective region are provided in the pixel region. A reflective layer for reflecting external light is provided in the reflective region of the TFT substrate 10.

  On the other hand, an infrared visible wavelength conversion glass 140 that converts visible light of each color of RGB is provided in the transmission region of the TFT substrate 10 for each pixel. It is not necessary to provide the infrared visible wavelength conversion glass 140 in the reflective region of the TFT substrate 10.

  On the other hand, each of the RGB color filters 28 is provided for each pixel on the counter substrate 20.

  Note that, due to the low conversion light rate of the infrared visible wavelength conversion glass 140, the intensity of visible light in the transmission region is lower than that in the reflection region. Therefore, in order to make the intensity of the emitted light uniform, the intensity of the color filter 28 may be different between the transmission area and the reflection area. That is, the color filter density in the reflection area may be set to be higher than the color filter density in the transmission area.

  In addition, the electro-optical device manufactured according to the present invention is not limited to the above-described illustrated examples, and various modifications can be made without departing from the scope of the present invention. For example, the above-described liquid crystal device has been described by taking an active matrix type liquid crystal display module using an active element (active element) such as a TFT (thin film transistor) as an example. The present invention can also be applied to an active matrix liquid crystal display module using active elements (active elements).

  Further, as an electronic device using the liquid crystal device manufactured according to the present invention, a projector of a light projection display device or a rear projector is shown as an example, but the present invention is not limited to this, and is applied to a direct-view type electronic device. May be.

  For example, an example in which the liquid crystal device described in this embodiment is applied to a portable computer will be described. FIG. 15 is a perspective view showing the configuration of this computer. In the figure, a computer 3100 includes a main body portion 3104 provided with a keyboard 3102 and a display portion 3101 provided with the liquid crystal device 1 or 201.

  At this time, when the infrared-visible wavelength conversion glass is not provided in the liquid crystal device to be arranged, that is, in the case of the liquid crystal device 201 of the second embodiment, the infrared-visible wavelength conversion glass 240 is replaced with a transmission type screen ( If the display portion 3101 having the (screen) is provided, an effect similar to that of this embodiment can be obtained.

  Next, an example in which the liquid crystal device described in this embodiment is applied to a mobile phone is described. FIG. 16 is a perspective view showing the configuration of this mobile phone. In the figure, a mobile phone 4200 includes a plurality of operation buttons 4202, an earpiece 4204, a mouthpiece 4206, and a display unit 4201 in which the liquid crystal device 1 or 201 is disposed.

  At this time, in the case where the infrared-visible wavelength conversion glass is not provided in the disposed liquid crystal device, that is, in the case of the liquid crystal device 201 of the second embodiment, the infrared-visible wavelength conversion glass 240 is replaced with a transmissive screen. If the (screen) display unit 4201 is provided, the same effect as in this embodiment can be obtained.

  In addition to the electronic devices described with reference to FIGS. 15 and 16, the liquid crystal device described in this embodiment includes portable information devices called PDA (Personal Digital Assistants), personal computers, digital computers, and the like. Still camera, in-vehicle monitor, digital video camera, LCD TV, viewfinder type, monitor direct view type video tape recorder, car navigation device, pager, electronic notebook, calculator, word processor, workstation, video phone, POS terminal, etc. Can be mentioned. Therefore, it goes without saying that the present invention can also be applied to these electronic devices.

1 is a plan view of a liquid crystal device showing a first embodiment of the present invention. Sectional drawing cut | disconnected along the II-II line | wire in FIG. FIG. 3 is a cross-sectional view of a liquid crystal device for explaining an operation of the liquid crystal device of FIGS. 1 and 2. The figure which shows the structure of the projector by which one liquid crystal device of FIGS. 1-3 was arrange | positioned. FIG. 4 is a diagram showing a configuration of a projector in which three liquid crystal devices of FIGS. 1 to 3 are arranged. The figure which shows the structure of the rear projector by which the liquid crystal device of FIGS. 1-3 was arrange | positioned. Sectional drawing of the liquid crystal device which shows the modification which formed the infrared visible wavelength conversion glass in the opposing board | substrate. FIG. 4 is a cross-sectional view illustrating a modification of the configuration of the liquid crystal device in FIG. 2. The figure which shows the structure of the infrared visible wavelength conversion glass in FIG. The front view of the opposing board | substrate of FIG. 8 which shows the arrangement | sequence of the infrared visible wavelength conversion glass of FIG. Sectional drawing which shows the outline of a structure of the liquid crystal device which shows 2nd Embodiment of this invention. FIG. 12 is a diagram showing a configuration of a projector in which one liquid crystal device of FIG. 11 is arranged. The figure which shows the structure of the rear projector by which the liquid crystal device of FIG. 11 was arrange | positioned. The front view of the screen which shows the arrangement | sequence of the infrared visible wavelength conversion glass of FIG. 12, FIG. The perspective view which shows the structure of the portable computer which is an electronic device. The perspective view which shows the structure of the mobile telephone which is an electronic device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Liquid crystal device, 9a ... Pixel electrode, 10 ... TFT substrate, 20 ... Counter substrate, 50 ... Liquid crystal, 140 ... Infrared visible wavelength conversion glass, 201 ... Liquid crystal device, 210 ... TFT substrate, 220 ... Counter substrate, 240 ... Infrared visible wavelength conversion glass, 1100 ... projector, 1102 ... infrared light generation unit, 1120 ... screen, 1200 ... projector, 1300 ... rear projector, 1304 ... screen, 2100 ... projector, 2300 ... rear projector, 3100 ... portable personal computer 3101 ... screen, 4200 ... mobile phone, 4201 ... screen.

Claims (13)

A substrate formed of single crystal silicon, transmitting infrared light having a wavelength longer than the wavelength of light corresponding to the band gap energy of the single crystal silicon, and having a semiconductor element formed thereon;
Infrared visible wavelength conversion means for converting the infrared light disposed on the infrared light emitting side of the substrate into visible light;
Have
An electro-optical device that performs image display with the visible light.   An element substrate having a plurality of switching elements and pixels formed in a display area, and a counter substrate disposed to face the element substrate, wherein the substrate is the element substrate or the counter substrate. The electro-optical device according to claim 1.   The electro-optical device according to claim 1, wherein the electro-optical device is transmissive or semi-transmissive. In an electro-optical device in which a pair of substrates are arranged to face each other,
The first substrate of the pair of substrates is formed of single crystal silicon, and emits infrared light having a wavelength longer than the wavelength of light corresponding to the band gap energy of the single crystal silicon constituting the first substrate. Transmitting, the semiconductor element is formed,
The second substrate of the pair of substrates includes an infrared visible wavelength conversion unit that is disposed to face the first substrate and converts the infrared light incident from the first substrate side into visible light,
An electro-optical device that performs image display with the visible light.   The electro-optical device according to claim 4, wherein the first substrate is an element substrate in which a plurality of switching elements and pixels are formed in a display region.   The said infrared visible wavelength conversion means is a material which converts the said infrared light into visible light of any wavelength band of red, green, and blue. Electro-optic device.   The infrared visible wavelength conversion means converts the infrared light into visible light in each red wavelength band, a material that converts visible light in the green wavelength band, and visible light in the blue wavelength band, respectively. 6. The electro-optical device according to claim 1, wherein the electro-optical device is made of a material to be converted.   The electro-optical device according to claim 2, wherein the wavelength conversion material is provided corresponding to the pixel.   The electro-optical device according to any one of claims 1 to 8, and an infrared light generating unit that generates infrared light having a wavelength longer than a wavelength of light corresponding to a band gap energy of the single crystal silicon constituting the substrate. And an electronic device. The electro-optical device;
A transmissive or reflective screen disposed on the output side of the electro-optical device;
The electronic apparatus according to claim 9, further comprising: A transmissive or semi-transmissive electro-optical device formed of a substrate that transmits infrared light and is formed of single crystal silicon;
Arranged on the infrared light incident side of the electro-optical device to generate infrared light having a wavelength longer than the wavelength of light corresponding to the band gap energy of the single crystal silicon constituting the element substrate and the counter substrate Means for generating infrared light;
Infrared visible wavelength conversion means for converting the infrared light disposed on the infrared light emitting side of the electro-optical device into visible light; and
A transmissive or reflective screen disposed on the output side of the electro-optical device;
Have
The electronic device according to claim 1, wherein the infrared visible wavelength converting means is disposed on the screen.   The electronic device according to claim 11, wherein the infrared visible wavelength conversion unit is a material that converts the infrared light into visible light having a wavelength band of red, green, or blue.   The infrared visible wavelength conversion means converts the infrared light into visible light in each red wavelength band, a material that converts visible light in the green wavelength band, and visible light in the blue wavelength band, respectively. The electronic device according to claim 11, wherein the electronic device is made of a material to be converted.

Images