Electro-optical device and electronic apparatus

By positioning temperature detection elements outside the display area and minimizing overlap with common potential wiring, the electro-optical device reduces noise interference and enhances temperature detection accuracy.

JP2025061999AActive Publication Date: 2025-04-11SEIKO EPSON CORP
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Patent Information

Application Number
JP2025014794
Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
Filing Date
2025-01-31
Publication Date
2025-04-11
Estimated Expiration
2041-09-10

AI Technical Summary

Technical Problem

In electro-optical devices, noise from signal wiring can interfere with temperature detection elements, reducing accuracy due to parasitic capacitance, even when constant potential wiring is used as a shield layer.

Method used

The electro-optical device includes wirings with an opening outside the display area and temperature detection elements positioned inside this opening. The temperature detection element is designed with diodes and an electrode, and is arranged to minimize overlap with the common potential wiring, reducing parasitic capacitance.

Benefits of technology

This configuration effectively reduces the influence of noise on the temperature detection element, enhancing the accuracy of temperature detection and improving the overall performance of the electro-optical device.

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Abstract

To provide an electro-optical device in which the output voltage of a temperature detection circuit is not easily affected by the parasitic capacitance between a temperature detection element and wiring, and an electronic apparatus.SOLUTION: In an electro-optical device 100, on the outside of a display area 10a, a temperature detection element 11 is provided in which a plurality of diodes D are electrically connected in series by relay parts P1, P2. On the outside of the display area 10a, common potential wiring 8a provided with an opening 8a0 is provided, and the temperature detection element 11 is located inside the opening 8a0 in plan view. With this, a parasitic capacitance with a large capacitance is not present between the relay parts P1,P2 and the common potential wiring 8a. On the inside of the opening 8a0 in plan view, an island-like light-shielding layer 8e on the same layer as the common potential wiring 8a is provided separate from the common potential wiring 8a.SELECTED DRAWING: Figure 7
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Description

[Technical field]

[0001] The present invention relates to an electro-optical device provided with a temperature detection element, and to an electronic device. [Background technology]

[0002] In electro-optical devices such as liquid crystal devices, a technology has been proposed in which a temperature detection element is provided outside the display area, and the driving conditions of the electro-optical device are corrected based on the detection results of the temperature detection element. In this case, if a signal wiring that supplies an AC signal is provided near the temperature detection element, the temperature detection element may be affected by potential changes in the signal wiring, resulting in a decrease in temperature detection accuracy. Therefore, it has been proposed to provide a constant potential wiring that applies a constant potential between the temperature detection element and the signal wiring as a shielding layer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-73810 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, even when a constant potential wiring is used as a shield layer, noise may occur in the constant potential applied to the constant potential wiring used as a shield layer when the electro-optical device is driven. As a result, if the noise affects the temperature detection element via the parasitic capacitance between the constant potential wiring and the temperature detection element, the temperature detection accuracy of the temperature detection element decreases. Therefore, when the wiring overlaps with the temperature detection element in a plan view, there is a problem that the temperature detection element is easily affected by the parasitic capacitance between the temperature detection element and the wiring. [Means for solving the problem]

[0005] In order to solve the above problems, one aspect of the electro-optical device of the present invention is characterized in that it comprises wiring having an opening outside a display area, and a temperature detection element provided outside the display area and inside the opening in a planar view.

[0006] Another aspect of the electro-optical device of the present invention comprises a temperature detection element provided outside a display area and wiring having a portion overlapping the temperature detection element in a planar view, the temperature detection element having a first diode, a second diode, and an electrode electrically connecting the first diode and the second diode in series, the first diode and the second diode being arranged along a first direction, and the electrode having a portion whose width in a direction along a second direction intersecting the first direction is narrower than the width in the direction along the second direction of a semiconductor layer constituting the first diode and a semiconductor layer constituting the second diode.

[0007] Yet another aspect of the electro-optical device of the present invention comprises a temperature detection element provided outside a display area, wiring having a portion overlapping with the temperature detection element in a planar view, and a complementary transistor having an N-channel transistor and a P-channel transistor outside the display area, wherein the temperature detection element has a first diode, a second diode, and an electrode electrically connecting the first diode and the second diode in series, and the distance between the semiconductor layer constituting the first diode and the semiconductor layer constituting the second diode is equal to or less than the distance between the semiconductor layer constituting the N-channel transistor and the semiconductor layer constituting the P-channel transistor.

[0008] Yet another aspect of the electro-optical device of the present invention comprises a plurality of data lines provided in a display area, a common potential wiring having a portion overlapping each of the plurality of data lines in a planar view, a temperature detection element overlapping with the wiring outside the display area in a planar view, a selection circuit electrically connected to each of the plurality of data lines, and a control circuit that controls the selection circuit for each horizontal scanning period during a precharge period, and is characterized in that the plurality of horizontal scanning periods include a first horizontal scanning period in which a precharge signal is supplied to a portion of the plurality of data lines, and a second horizontal scanning period in which the precharge signal is supplied to another portion of the plurality of data lines that is different from the first portion.

[0009] Yet another aspect of the electro-optical device of the present invention comprises a plurality of data lines provided in a display area, a common potential wiring having a portion overlapping each of the plurality of data lines in a planar view, a temperature detection element overlapping with the wiring outside the display area in a planar view, a selection circuit electrically connected to each of the plurality of data lines, and a control circuit that controls the selection circuit for each horizontal scanning period during a precharge period, and is characterized in that the plurality of horizontal scanning periods include a first horizontal scanning period in which a precharge signal is supplied to all of the plurality of data lines, and a second horizontal scanning period in which a precharge signal is not supplied to any of the plurality of data lines.

[0010] The electro-optical device according to the present invention is used in electronic equipment. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a plan view showing an example of the configuration of an electro-optical device according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is an explanatory diagram that illustrates a cross section of the electro-optical device illustrated in FIG. [Diagram 3] 3 is a circuit block diagram showing an electrical configuration of the first substrate shown in FIG. 2. [Figure 4] FIG. 4 is an explanatory diagram of a data line driving circuit and the like shown in FIG. [Diagram 5] 2 is a timing chart for displaying an image in the electro-optical device shown in FIG. [Figure 6] FIG. 4 is an explanatory diagram of a temperature detection circuit shown in FIG. [Figure 7] 7 is an explanatory diagram showing a cross section of the temperature detection element and the like shown in FIG. 6. [Figure 8] FIG. 2 is an explanatory diagram of a comparative example to the first embodiment of the present invention. [Figure 9] FIG. 13 is a diagram showing the relationship between precharge and the output voltage of the temperature detection circuit. [Figure 10] 4 is a graph showing the effect of a parasitic capacitance of the temperature detection element shown in FIG. 3 on the output voltage of the temperature detection circuit. [Figure 11] FIG. 5 is an explanatory diagram of an electro-optical device according to a second embodiment of the present invention. [Figure 12] 12 is an explanatory diagram showing a cross section of the temperature detection element and the like shown in FIG. 11 . [Figure 13] FIG. 11 is an explanatory diagram of an electro-optical device according to a modified example of the second embodiment of the present invention. [Figure 14] FIG. 11 is an explanatory diagram of an electro-optical device according to a third embodiment of the present invention. [Figure 15] FIG. 15 is a cross-sectional view of the temperature detection element shown in FIG. [Figure 16] FIG. 11 is an explanatory diagram of an electro-optical device according to a first modified example of the third embodiment of the present invention. [Figure 17] FIG. 11 is an explanatory diagram of an electro-optical device according to Modification 2 of Embodiment 3 of the present invention. [Figure 18] 13 is an explanatory diagram of precharging in an odd-numbered frame of an electro-optical device according to a fourth embodiment of the present invention. FIG. [Figure 19] 10 is an explanatory diagram of precharging in an even-numbered frame of an electro-optical device according to a fourth embodiment of the present invention. [Figure 20] 13 is an explanatory diagram of precharging of an electro-optical device according to a fifth embodiment of the present invention. [Figure 21] 1 is a block diagram showing an example of the configuration of a projection display device to which the present invention is applied. [Figure 22] FIG. 22 is an explanatory diagram of the light path shift element shown in FIG. 21 . DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] An embodiment of the present invention will be described with reference to the drawings. In the drawings referred to in the following description, each layer and each member is shown at a different scale so that each layer and each member can be recognized on the drawing. In addition, when describing the arrangement of layers formed on the first substrate, the upper layer side or the surface side means the side opposite to the side where the substrate body of the first substrate is located (the side where the counter substrate and the liquid crystal layer are located), and the lower layer side means the side where the substrate body of the first substrate is located. In describing the arrangement of layers formed on the second substrate, the upper layer side or the surface side means the side opposite to the side where the substrate body of the counter substrate is located (the side where the first substrate and the liquid crystal layer are located), and the lower layer side means the side where the substrate body of the second substrate is located. In addition, in the present invention, "planar view" means a state seen from the normal direction to the first substrate 10 or the second substrate 20.

[0013] 1. Embodiment 1 1-1. Specific configuration of the electro-optical device 100 FIG. 1 is a plan view showing an example of the configuration of an electro-optical device 100 according to a first embodiment of the present invention. FIG. 2 is an explanatory diagram showing a schematic cross section of the electro-optical device 100 shown in FIG. 1. The electro-optical device 100 shown in FIG. 1 and FIG. 2 is a liquid crystal device, and has an electro-optical panel 100p made of a liquid crystal panel. In the electro-optical device 100, the first substrate 10 and the second substrate 20 are bonded together with a predetermined gap by a sealant 107, and the sealant 107 is provided in a frame shape along the outer edge of the second substrate 20. The sealant 107 is an adhesive made of a photocurable resin, a thermosetting resin, or the like, and is mixed with a gap material 107a such as glass fiber or glass beads for setting the distance between the two substrates to a predetermined value. In the electro-optical device 100, an electro-optical layer 50 made of a liquid crystal layer is provided in the area surrounded by the sealant 107 between the first substrate 10 and the second substrate 20. The sealant 107 has a discontinuous portion 107c formed therein to be used as a liquid crystal injection port, and the discontinuous portion 107c is sealed with a sealant 108 after the liquid crystal material is injected. When the liquid crystal material is injected by a dropping method, the discontinuous portion 107c is not formed. The first substrate 10 and the second substrate 20 are both rectangular, and the display area 10a is provided as a rectangular area in the approximate center of the electro-optical device 100. Corresponding to this shape, the sealant 107 is also provided in an approximately rectangular shape, and the outside of the display area 10a is a peripheral area 10c in the shape of a rectangular frame.

[0014] In the display area 10a, when two sides extending in the X direction are defined as a first side 10a1 and a second side 10a2, and two sides extending in the Y direction are defined as a third side 10a3 and a fourth side 10a4, in the peripheral area 10c of the first substrate 10, a data line driving circuit 101 is provided between an end of the first substrate 10 and the first side 10a1 of the display area 10a, and an inspection circuit 105 is provided between the end of the first substrate 10 and the second side 10a2 of the display area 10a. In addition, a scanning line driving circuit 104 is provided between the end of the first substrate 10 and the third side 10a3 of the display area 10a, and between the end of the first substrate 10 and the fourth side 10a4 of the display area 10a. Among the ends of the first substrate 10, at the end on the side of the data line driving circuit 101, mounting terminals 102 to which the wiring substrate 70 is electrically connected are arranged. A driving IC 75 including a control circuit 76 that outputs image signals VID1, VID2, ... VID2n and selection signals SEL1, SEL2, ... SEL8, etc., which will be described later with reference to Fig. 5, is mounted on the wiring board 70. The wiring board 70 is electrically connected to a higher-level circuit 60 via a connector 61. The higher-level circuit 60 is provided with an image control circuit 65. The higher-level circuit 60 is also provided with a temperature detection driving circuit 66 that drives a temperature detection circuit 1, which will be described later. The higher-level circuit 60 is provided in a higher-level device for the electro-optical device 100 in an electronic device, which will be described later.

[0015] The first substrate 10 has a translucent substrate body 10w such as a quartz substrate or a glass substrate, and a plurality of pixel transistors and pixel electrodes 9a electrically connected to each of the plurality of pixel transistors are formed in a matrix in a display region 10a on one surface 10s of the first substrate 10. A first alignment film 16 is formed on the upper layer side of the pixel electrodes 9a. On the one surface 10s of the first substrate 10, a rectangular frame region 10b extending between the display region 10a and the sealant 107 has dummy pixel electrodes 9b formed simultaneously with the pixel electrodes 9a in portions extending along each side of the display region 10a.

[0016] The second substrate 20 has a light-transmitting substrate body 20w such as a quartz substrate or a glass substrate, and a common electrode 21 is formed on one surface 20s of the second substrate 20. The common electrode 21 is formed on substantially the entire surface of the one surface 20s of the second substrate 20. In the frame region 10b on the one surface 20s of the second substrate 20, a light-shielding border 29 is formed below the common electrode 21, and a second alignment film 26 is laminated on the surface of the common electrode 21. The display region 10a is defined by the inner edge of the border 29. A light-transmitting planarizing film 22 is formed between the border 29 and the common electrode 21. The light-shielding layer constituting the border 29 may be formed as a black matrix portion overlapping the inter-pixel region 10f sandwiched between the adjacent pixel electrodes 9a. The border 29 is formed at a position overlapping the dummy pixel electrodes 9b in a plan view. The border 29 is made of a light-shielding metal film or black resin.

[0017] The first alignment film 16 and the second alignment film 26 are made of, for example, SiO X (x≦2), TiO2, M It is an inorganic alignment film made of obliquely evaporated films of SiO, Al2O3, etc., and has pillar-shaped structures called columns. The electro-optical device 100 is composed of a columnar structure layer formed at an angle with respect to the first substrate 10 and the second substrate 20. Therefore, the first alignment film 16 and the second alignment film 26 align the nematic liquid crystal molecules with negative dielectric anisotropy used in the electro-optical layer 50 at an oblique angle with respect to the first substrate 10 and the second substrate 20, thereby providing a pretilt to the liquid crystal molecules. In this way, the electro-optical device 100 is configured as a normally black VA (Vertical Alignment) mode liquid crystal device.

[0018] On the first substrate 10, outside the sealing material 107, inter-substrate conduction electrode portions 14t are formed at positions overlapping with four corner portions 24t of the second substrate 20. The inter-substrate conduction electrode portions 14t are electrically connected to the wiring 6g, and the wiring 6g is electrically connected to a terminal 102g of the terminal 102 for supplying a common potential LCCOM. An inter-substrate conductive material 109 containing conductive particles is disposed between the inter-substrate conduction electrode portions 14t and the corner portions 24t, and the common electrode 21 of the second substrate 20 is electrically connected to the first substrate 10 side via the inter-substrate conduction electrode portions 14t and the inter-substrate conductive material 109. Therefore, the common potential LCCOM is applied to the common electrode 21 from the first substrate 10 side.

[0019] The terminals 102 include terminals 102d, 102h, 102f, 102t, 102s, 102g, 102c, and 102a. The terminal 102d is a terminal for supplying a start pulse SP to the scanning line driving circuit 104. The terminal 102h is a terminal for supplying a clock signal CLY to the scanning line driving circuit 104. The terminal 102f is a terminal for supplying an output control signal ENBY to the scanning line driving circuit 104. The terminal 102t is a terminal for supplying a high-level constant potential VDDY to the scanning line driving circuit 104. The terminal 102s is a terminal for supplying a low-level constant potential VSSY to the scanning line driving circuit 104. The terminal 102g is a terminal for supplying a common potential LCCOM. The cathode terminal 102c and the anode terminal 102a are terminals electrically connected to a cathode wiring Lc and an anode wiring La of the temperature detection circuit 1, which will be described later with reference to FIG. 3, respectively.

[0020] The electro-optical device 100 of this embodiment is a transmissive liquid crystal device. Therefore, the pixel electrodes 9a and the common electrode 21 are formed of a light-transmitting conductive layer such as an ITO (Indium Tin Oxide) film or an IZO (Indium Zinc Oxide) film. In such a transmissive liquid crystal device, for example, light from a light source incident from the second substrate 20 side is modulated while being emitted from the first substrate 10 to display an image. If the pixel electrodes 9a are made of a reflective metal such as aluminum, the electro-optical device 100 can be a reflective liquid crystal device.

[0021] 1-2. Electrical configuration of the electro-optical device 100 FIG. 3 is a circuit block diagram showing the electrical configuration of the first substrate 10 shown in FIG. 2. In FIG. 3, the first substrate 10 has a display area 10a in which a plurality of pixels 100a are arranged in a matrix in a substantially central area. In the first substrate 10, a plurality of scanning lines 3a extending in the X direction from a scanning line driving circuit 104 and a plurality of data lines 6a extending in the Y direction from a data line driving circuit 101 are provided inside the display area 10a, and pixels 100a are formed corresponding to the intersections of the scanning lines 3a and the data lines 6a. The plurality of data lines 6a are electrically connected to an inspection circuit 105 arranged on the second side 10a2 side of the display area 10a. In each of the plurality of pixels 100a, a pixel transistor 30 made of an N-channel transistor and a pixel electrode 9a electrically connected to the pixel transistor 30 are formed. A data line 6a is electrically connected to a source region of the pixel transistor 30, a scanning line 3a is electrically connected to a gate of the pixel transistor 30, and a pixel electrode 9a is electrically connected to a drain region of the pixel transistor 30. An image signal VID is supplied to the data line 6a by a data line driving circuit 101, and a scanning signal G is supplied to the scanning line 3a.

[0022] As described later, the data line driving circuit 101 is used as part of a precharge circuit 106 that applies a precharge signal to the data line 6a during a precharge period set at the beginning of each horizontal scanning period. Although not shown, the inspection circuit 105 is a transistor array. One source-drain region of the transistor in the inspection circuit 105 is electrically connected to the data line 6a, the other source-drain region is electrically connected to an inspection line (not shown), and the gate is electrically connected to a control signal line (not shown) in the inspection circuit 105.

[0023] In each pixel 100a, the pixel electrode 9a faces the common electrode 21 of the second substrate 20 described with reference to Fig. 2 via the electro-optical layer 50 to form a liquid crystal capacitance 50a. In each pixel 100a, a storage capacitance 55 is added in parallel with the liquid crystal capacitance 50a to prevent fluctuations in the image signal VID stored in the liquid crystal capacitance 50a. In this embodiment, in order to form the storage capacitance 55, a common potential wiring 8a extending across the multiple pixels 100a is formed as a capacitance line on the first substrate 10, and a common potential LCCOM is supplied to the common potential wiring 8a. The common potential wiring 8a is provided so as to overlap at least one of the scanning line 3a and the data line 6a in a plan view. FIG. 3 illustrates an example in which the common potential wiring 8a overlaps both the scanning line 3a and the data line 6a in a plan view. The common potential wiring 8a may be configured so as to overlap the data line 6a of the scanning line 3a and the data line 6a in a plan view. In either case, the common potential wiring 8a has a portion overlapping with the data line 6a. In the first substrate 10, the temperature detection circuit 1 is configured outside the display area 10a. In FIG. 3, the scanning line driving circuit 104 arranged on the left side of the display area 10a drives the odd-numbered scanning lines 3a, and the scanning line driving circuit 104 arranged on the right side of the display area 10a drives the even-numbered scanning lines 3a. However, the same scanning line 3a may be driven by the scanning line driving circuits 104 arranged on both the left and right sides.

[0024] 1-3. Configuration example of data line driving circuit 101 etc. FIG. 4 is an explanatory diagram of the data line driving circuit 101 and the like shown in FIG. 3. FIG. 5 is a timing chart when an image is displayed in the electro-optical device 100 shown in FIG. 1. As shown in FIG. 4, the data line driving circuit 101 is disposed on the first side 10a1 of the display area 10a of the first substrate 10. The data line driving circuit 101 includes a demultiplexer, and the demultiplexer includes a selection circuit 101a as a sample-and-hold circuit. The data lines 6a extend from the selection circuit 101a in the Y direction, that is, toward the second side 10a2 of the display area 10a. The selection circuit 101a includes a transistor 30e that controls the electrical connection between the data lines 6a and the image signal wiring 6j. In this embodiment, the demultiplexer includes, for example, eight transistors 30e. The transistors 30e are N-channel transistors. Therefore, in the case of the FHD standard, 1920 / 8=240, so 240 demultiplexers are provided. The data line driving circuit 101 supplies an image signal VID to each data line 6a from the driving IC 75 shown in Fig. 3 via the terminal 102 and the image signal wiring 6j. At that time, the transistor 30e of the selection circuit 101a supplies the image signal VID to each data line 6a in a time-division manner based on the selection signals SEL1, SEL2, ..., SEL8 supplied from the control circuit 76 of the driving IC 75 via the control signal line 6i.

[0025] 5, when an image is displayed in the electro-optical device 100, the scanning line driving circuit 104 sequentially and exclusively sets the scanning signals G1, G2, G3, ..., Gm to the selection level for each horizontal scanning period H during an Nth frame period defined by a vertical synchronization signal Vsync. During the horizontal scanning period H, the selection signals SEL1, SEL2, ..., SEL8 sequentially and exclusively set to the selection level, and the driving IC 75 supplies the image signals VID1, VID2, ..., VIDn in synchronization with the selection signals SEL1, SEL2, ..., SEL8.

[0026] For example, in a horizontal scanning period H in which the scanning signal G1 is at the selection level, when the selection signal SEL1 is at the selection level, voltages corresponding to the image signals VID1, VID2, . . . VIDn are written to the pixel 100a corresponding to the intersection of the first row scanning line 3a and the data line 6a located at the first position in the X direction in each of the multiple demultiplexers. Next, when the selection signal SEL2 is at the selection level, voltages corresponding to the image signals VID1, VID2, . . . VIDn are written to the pixel 100a corresponding to the intersection of the first row scanning line 3a and the data line 6a located at the second position in the first direction in each of the multiple demultiplexers. Similarly, when the selection signals SEL3 to SEL8 are at the selection level, voltages corresponding to the image signals VID1 to VIDn are written to the corresponding pixels 100a.

[0027] Furthermore, in driving the electro-optical device 100, a preliminary write is performed before writing an image signal voltage to the data lines 6a in order to improve display quality. This is generally called precharging. Therefore, at the beginning of the horizontal scanning period H, a precharge period tp is provided in which the selection signals SEL1, SEL2, ... SEL8 are simultaneously at the selection level. In the precharge period tp, the selection signals SEL1, SEL2, ... SEL8 are all at the selection level, so that the precharge signal PRC is supplied to all the data lines 6a. Therefore, the control circuit 76 controls the selection circuit 101a in the precharge period tp, and the control circuit 76 and the selection circuit 101a constitute a precharge circuit.

[0028] This operation is performed in each horizontal period H. Also, in the N+1th frame after the Nth frame, a similar operation is performed. At that time, the image signal polarity for each pixel 100a may be switched. The image signal polarity is the polarity of the image signal voltage when the common potential LCCOM is used as a reference. For example, if the image signal voltage is positive with respect to the common potential LCCOM, the image signal voltage is positive, and if the image signal voltage is negative with respect to the common potential LCCOM, the image signal voltage is negative. For example, if positive polarity writing is performed in the Nth frame, negative polarity writing is performed in the next N+1th frame. On the other hand, if negative polarity writing is performed in the Nth frame, positive polarity writing is performed in the next N+1th frame. By performing such polarity inversion, deterioration of the electro-optical layer 50 can be prevented.

[0029] In this manner, in this embodiment, the precharge assists in writing the image signal voltage, or reduces crosstalk, in which the upper and lower parts of a white window are visually perceived as having a different gradation from the surroundings when a white window is displayed on a halftone background. The precharge signal PRC is often set, for example, near the lowest voltage in the voltage range of the image signal VID. For example, in the normally black mode electro-optical device 100, the common potential LCCOM is set to a fixed potential of 7V, the image signal voltage in negative polarity display is set to 2V (white) to 7V (black), the image signal voltage in positive polarity display is set to 7V (black) to 12V (white), and the precharge signal is set to about 2V to 4V. In practice, the common potential LCCOM is adjusted in consideration of the push-down voltage in the transistor 30e of the selection circuit 101a and the pixel transistor 30, but it can be ignored in the description of the embodiment.

[0030] Precharging is generally performed at the beginning of the horizontal scanning period H. Therefore, the potentials of the data lines 6a all transition to around 2V at the same time, causing relatively large noise in the potential of the common potential wiring 8a due to parasitic capacitance. In detail, as shown by LCCOM in FIG. 5, spike noise toward the lower potential side of the common potential LCCOM occurs in the common potential wiring 8a in synchronization with the precharging. Noise also occurs when writing image signals to each pixel, but it is relatively small because of the time-division operation. In recent years, the number of data lines 6a in the display area 10a has increased due to the trend toward higher resolution, and this spike noise has become difficult to suppress.

[0031] 1-4. Temperature detection circuit 1 configuration Fig. 6 is an explanatory diagram of the temperature detection circuit 1 shown in Fig. 3. Fig. 6 shows a circuit configuration when the temperature detection circuit 1 detects the temperature.

[0032] 3, a temperature detection circuit 1 that detects the temperature of the electro-optical panel 100p is provided outside the display area 10a of the first substrate 10. The temperature detection circuit 1 includes a temperature detection element 11 and an electrostatic protection circuit 12 for protecting the temperature detection element 11 from a surge current. On the first substrate 10, the temperature detection element 11 is disposed near the display area 10a, and the electrostatic protection circuit 12 is provided between the temperature detection element 11 and an end of the first substrate 10 where the terminals 102 are arranged.

[0033] As shown in FIG. 6, the temperature detection element 11 includes, for example, a plurality of diodes D electrically connected in series. For ease of explanation, FIG. 6 illustrates an example in which three diodes D (D1 to D3) are electrically connected in series, but five or six diodes D may be electrically connected in series. With such a temperature detection element 11, when a constant current is passed through the temperature detection element 11, the sensitivity of the forward voltage to temperature can be set to approximately −10 mV / ° C. An anode wiring La extending from an anode terminal 102a is electrically connected to an anode 11a of the temperature detection element 11. A cathode wiring Lc extending from a cathode terminal 102c is electrically connected to a cathode 11c of the temperature detection element 11. A ground potential GND is supplied to the cathode wiring Lc.

[0034] Therefore, when the electro-optical device 100 is mounted on an electronic device, if a minute forward drive current IF of about 100 nA to several μA is supplied from the temperature detection drive circuit 66 of the upper circuit 60 to the temperature detection circuit 1 via the anode terminal 102a and the cathode terminal 102c through the wiring board 70, most of the drive current IF flows through the temperature detection element 11. Here, the forward voltage of the temperature detection element 11 can be considered to have a good linear relationship with temperature. Therefore, if the output voltage VF between the anode terminal 102a and the cathode terminal 102c when the drive current IF consisting of a constant current of about 100 nA to several μA is supplied to the temperature detection element 11 by the temperature detection drive circuit 66, the temperature of the display area 10a of the electro-optical panel 100p can be detected. More specifically, in the specified temperature range when the electro-optical device 100 is used as a light valve or the like of a projection display device described later, the output voltage VF changes with good linearity with respect to temperature, so that if it is calibrated in advance, the temperature of the electro-optical panel 100p can be detected. At that time, since the temperature detection element 11 is arranged in the vicinity of the display area 10a, the temperature detection element 11 can properly detect the temperature of the display area 10a. Therefore, if the image signal is corrected based on the temperature detection by the temperature detection circuit 1, the electro-optical device 100 can be driven under proper conditions corresponding to the temperature of the display area 10a, so that a high-quality image can be displayed. The temperature detection drive circuit 66 includes a constant current circuit 661 and a stabilizing capacitance 662. The stabilizing capacitance 662 is provided between the constant current circuit 661 and the ground potential GND, and stabilizes the measured value of the output voltage VF. The electrostatic capacitance of the stabilizing capacitance 662 is, for example, 0.1 μF.

[0035] In this embodiment, the electrostatic protection circuit 12 includes a transistor Tr connected between an anode wiring La and a cathode wiring Lc, and the transistor Tr is electrically connected in parallel to the temperature detection element 11. One source-drain region 31i of the transistor Tr is electrically connected to the cathode wiring Lc between the cathode terminal 102c and the cathode 11c of the temperature detection element 11, and the other source-drain region 31j of the transistor Tr is electrically connected to the anode wiring La between the anode terminal 102a and the anode 11a of the temperature detection element 11. In this embodiment, the transistor Tr is an N-channel transistor, similar to the pixel transistor 30.

[0036] In the electrostatic protection circuit 12, the first capacitance element C1 and the second capacitance element C2 electrically connected in series are electrically connected between the anode wiring La and the cathode wiring Lc. More specifically, one electrode of the second capacitance element C2 is electrically connected to the anode wiring La, one electrode of the first capacitance element C1 is electrically connected to the cathode wiring Lc, and the other electrode of the first capacitance element C1 and the other electrode of the second capacitance element C2 are electrically connected. One electrode of the first capacitance element C1 is electrically connected to the cathode wiring Lc between the cathode terminal 102c and one source-drain region 31i of the transistor Tr, and one electrode of the second capacitance element C2 is electrically connected to the anode wiring La between the anode terminal 102a and the other source-drain region 31j of the transistor Tr. The capacitance of the first capacitance element C1 and the second capacitance element C2 is, for example, 5 pF.

[0037] The anode line La has a first resistor R1 between the anode terminal 102a and a connection position between the anode line La and the second capacitance element C2, and the cathode line Lc has a second resistor R2 between the cathode terminal 102c and a connection position between the cathode line Lc and the first capacitance element C1. A connection node Cn between the first capacitance element C1 and the second capacitance element C2 is electrically connected to the gate electrode 33t of the transistor Tr. The first resistance element R1 and the second resistance element R2 are, for example, 10 kΩ.

[0038] The electrostatic protection circuit 12 has a resistive element R3 electrically connected in parallel to the first capacitance element C1. More specifically, the gate wiring Lg extending from the gate electrode 33t of the transistor Tr is electrically connected to the connection node Cn between the first capacitance element C1 and the second capacitance element C2, and is further electrically connected to the cathode wiring Lc via the resistive element R3. The resistive element R3 is, for example, 500 kΩ. The transistor Tr functions as a discharge path. Since the gate electrode 33t of the transistor Tr is electrically connected to the cathode wiring Lc via the resistive element R3, the gate electrode 33t and the cathode wiring Lc are at the same potential in a static state. In other words, the gate-source voltage of the transistor Tr is 0V. Therefore, the transistor Tr is turned off, and ideally, no current flows between the source and drain. Therefore, when the temperature is detected by the temperature detection element 11, the drive current IF supplied to the anode wiring La does not flow through the transistor Tr, but flows through the temperature detection element 11.

[0039] In this manner, the electrostatic protection circuit 12 includes a transistor Tr electrically connected in parallel to the temperature detection element 11, a first capacitance element C1 electrically connected to the transistor Tr, and a resistance element R3 electrically connected in parallel to the first capacitance element C1. The electrostatic protection circuit 12 also includes a second capacitance element C2 electrically connected in series to the first capacitance element C1. Therefore, when a surge current caused by static electricity flows in from the anode terminal 102a during a manufacturing process or the like, the electrostatic protection circuit 12 protects the temperature detection element 11 from static electricity.

[0040] More specifically, in the electrostatic protection circuit 12, in a static state, the gate-source voltage of the transistor Tr is 0V, and the transistor Tr is off. When a surge current caused by static electricity flows in from the anode terminal 102a, the voltage fluctuation is suppressed by the first resistance element R1, and the potential of the gate electrode 33t of the transistor Tr, which is the potential of the connection node Cn between the first capacitance element C1 and the second capacitance element C2, rises. As a result, the transistor Tr is turned on, and the surge current flows to the cathode terminal 102c through the transistor Tr and the cathode wiring Lc. At that time, the first resistance element R1 reduces the surge current that flows in from the anode terminal 102a, and the second resistance element R2 reduces the surge current that flows in from the cathode terminal 102c. The period during which the transistor Tr is on is determined by the first capacitance element C1, the second capacitance element C2, the resistance element R3, and the gate capacitance of the transistor Tr. After discharging, the gate-source voltage of transistor Tr returns to 0 V due to resistance element R3. Therefore, the surge current flowing through temperature detection element 11 is suppressed by electrostatic protection circuit 12, so that temperature detection element 11 can be protected.

[0041] 1-5. Example of configuration of temperature detection element 11, etc. Fig. 7 is an explanatory diagram showing a cross section of the temperature detection element 11 and the like shown in Fig. 6. As shown in Fig. 7, in the first substrate 10, a light-transmitting insulating layer 41 made of a silicon oxide film or the like is formed on the substrate body 10w, and a pixel transistor 30 having a semiconductor layer 31a is formed on the surface side of the insulating layer 41. A light-shielding layer (not shown) may be formed between the substrate body 10w and the insulating layer 41 so as to overlap the semiconductor layer 31a and the like in a planar view. Note that, for ease of identification in the drawing, the gate insulating layer 32 is drawn only on the pixel transistor 30.

[0042] The pixel transistor 30 includes a semiconductor layer 31a and a gate electrode 33g made of a part of the scanning line 3a intersecting with the semiconductor layer 31a. Between the semiconductor layer 31a and the gate electrode 33g, a light-transmitting gate insulating layer 32 made of a silicon oxide film or the like is provided. The gate electrode 33g is, for example, a laminated film of tungsten silicide and conductive polysilicon. The semiconductor layer 31a is made of a polysilicon film. The pixel transistor 30 has an LDD (Lightly Doped Drain) structure. More specifically, in the pixel transistor 30, the source region 31s includes a high-concentration region 31s1 separated from the channel region 31g and a low-concentration region 31s2 sandwiched between the channel region 31g and the high-concentration region 31s1, and the drain region 31d includes a high-concentration region 31d1 separated from the channel region 31g and a low-concentration region 31d2 sandwiched between the channel region 31g and the high-concentration region 31d1. The gate insulating layer 32 is made of, for example, a silicon oxide film. Note that a light-shielding layer formed between the substrate body 10w and the insulating layer 41 may be used as the scanning line 3a, and the gate electrode 33g may be electrically connected to the light-shielding layer via a contact hole (not shown) penetrating the gate insulating layer 32 and the insulating layer 41.

[0043] On the upper side of the gate electrode 33g, light-transmitting insulating layers 42, 43, and 44 made of a silicon oxide film or the like are laminated in this order, and a conductive layer is formed between the insulating layers 41, 42, and 43 to form the storage capacitor 55 described with reference to Figure 3.

[0044] A data line 6a and a relay electrode 6b are formed between the insulating layer 42 and the insulating layer 43. The data line 6a is electrically connected to the source region 31s of the pixel transistor 30 via a contact hole 42s that penetrates the gate insulating layer 32 and the insulating layer 42. The relay electrode 6b is electrically connected to the drain region 31d of the pixel transistor 30 via a contact hole 42d that penetrates the gate insulating layer 32 and the insulating layer 42. The data line 6a and the relay electrode 6b are made of a conductive layer that is simultaneously formed in the same layer, and are, for example, low-resistance wiring mainly made of aluminum.

[0045] A common potential wiring 8a and a relay electrode 8d are formed between the insulating layer 43 and the insulating layer 44. The common potential wiring 8a and the relay electrode 8d are made of conductive layers simultaneously formed in the same layer. The relay electrode 8d is electrically connected to the relay electrode 6b via a contact hole 43d penetrating the insulating layer 43. Although not shown, the common potential wiring 8a is electrically connected to one electrode of the storage capacitor 55, and the other electrode of the storage capacitor 55 is electrically connected to the relay electrodes 6b and 8d. The common potential wiring 8a is also electrically connected to the wiring 6g in FIG. 1.

[0046] A pixel electrode 9a is formed on the insulating layer 44. The pixel electrode 9a is electrically connected to the relay electrode 8d via a contact hole 44d that penetrates the insulating layer 44. Therefore, the pixel electrode 9a is electrically connected to the other electrode of the storage capacitor 55, and is further electrically connected to the drain region 31d of the pixel transistor 30.

[0047] Although not shown in the figure, the first substrate 10 also includes transistors for driving circuits that constitute inverter circuits, etc. in the scanning line driving circuit 104, and transistors for driving circuits that constitute the selection circuit 101a of the data line driving circuit 101, which are fabricated using the manufacturing process for the pixel transistors 30, etc.

[0048] The first substrate 10 is configured with the diode D of the temperature detection element 11 by utilizing the manufacturing process of the pixel transistor 30, the transistor for the driving circuit, and the like. More specifically, in the first substrate 10, a plurality of semiconductor layers 31h separated from each other in an island shape are provided on the upper layer of the insulating layer 41, and each of the plurality of semiconductor layers 31h is provided with an N-type region and a P-type region. In this embodiment, the N-type region includes a high-concentration N-type region N+ and a low-concentration N-type region N-, and the P-type region includes a high-concentration P-type region P+ and a low-concentration P-type region P-, and the low-concentration N-type region N- and the low-concentration P-type region P- form a PN junction. The diode D can also be configured with a high-concentration P-type region P+, a low-concentration N-type region N-, and a high-concentration N-type region N+. In either case, whether or not it is a diode D can be determined by measuring its electrical characteristics.

[0049] Electrodes 6e1 and 6e2 are formed on the upper layer of the insulating layer 42, and the multiple electrodes 6e1 and 6e2 are electrically connected to a high-concentration P-type region P+ of the semiconductor layer 31h and a high-concentration N-type region N+ of the adjacent semiconductor layer 31h via contact holes 42p and 42n that penetrate the insulating layer 42. The relay portion P1 is a portion that electrically connects the PN junction of the first diode D1 and the PN junction of the second diode D2, and includes the N-type region of the first diode D1, the electrode 6e1, and the P-type region of the second diode D2, and the relay portion P2 is a portion that electrically connects the PN junction of the second diode D2 and the PN junction of the third diode D3, and includes the N-type region of the second diode D2, the electrode 6e2, and the P-type region of the third diode D3. Therefore, the electrode 6e1 is included in the relay portion P1 that electrically connects the first diode D1 and the second diode D2, and the electrode 6e2 is included in the relay portion P2 that electrically connects the second diode D2 and the third diode D3. Here, the electrode 6e1 corresponds to a portion that electrically connects the semiconductor layer 31h of the first diode D1 and the semiconductor layer 31h of the second diode D2, and the electrode 6e2 corresponds to a portion that electrically connects the semiconductor layer 31h of the second diode D2 and the semiconductor layer 31h of the third diode D3.

[0050] In addition, an anode wiring La is electrically connected to the high-concentration P-type region P+ of the semiconductor layer 31h arranged at one end via a contact hole 42p, and a cathode wiring Lc is electrically connected to the high-concentration N-type region N+ of the semiconductor layer 31h arranged at the other end via a contact hole 42n.

[0051] The semiconductor layer 31h is formed simultaneously in the same layer as the semiconductor layer 31a, and therefore has the same thickness as the semiconductor layer 31a. The N-type region and the P-type region are formed by utilizing the manufacturing process of the driving transistors constituting the scanning line driving circuit 104 and the like shown in Fig. 3, and the pixel transistors 30. The electrodes 6e1 and 6e2 are formed simultaneously in the same layer as the data line 6a, for example.

[0052] Although not shown, the transistor Tr, the first resistor element R1, the second resistor element R2, and the resistor element R3 of the electrostatic protection circuit 12 are formed using each conductive layer and the like shown in FIG. 7. For example, the first resistor element R1, the second resistor element R2, and the resistor element R3 are made of a conductive polysilicon film and the like. For example, they are provided in the same layer as the gate electrode 33g and the semiconductor layer 31a. The first resistor element R1, the second resistor element R2, and the resistor element R3 may be made of a metal material such as tungsten silicide or aluminum, without being limited thereto. The transistor Tr is formed simultaneously in the same layer as the pixel transistor 30. The first capacitance element C1 and the second capacitance element C2 are formed simultaneously in the same layer as the storage capacitance 55.

[0053] As shown in FIG. 4 and FIG. 7, the common potential wiring 8a is a wiring extending from the terminal 102g through the formation region of the temperature detection element 11 toward the display region 10a and the scanning line driving circuit 104. Here, the common potential wiring 8a has an opening 8a0 provided outside the display region 10a, and the temperature detection element 11 is formed inside the opening 8a0 in a plan view. In this embodiment, a light-shielding layer 8e is formed inside the opening 8a0 in a plan view, overlapping with the temperature detection element 11 in a plan view. The light-shielding layer 8e is a light-shielding conductive layer formed simultaneously in the same layer as the common potential wiring 8a. The light-shielding layer 8e is a film formed simultaneously in the same layer as the common potential wiring 8a, but is provided separately from the common potential wiring 8a.

[0054] The parting 29 of the second substrate 20 is formed in a region overlapping with the temperature detection element 11 in a planar view, and the parting 29 is further formed in a region overlapping with the data line driving circuit 101 and the scanning line driving circuit 104 in a planar view.

[0055] In the first substrate 10 configured in this manner, the data line 6a and electrodes 6e1, 6e2, etc. formed between the insulating layer 42 and the insulating layer 43 correspond to a first conductive layer, the common potential wiring 8a and the light-shielding layer 8e, etc. formed between the insulating layer 43 and the insulating layer 44 correspond to a second conductive layer, and the pixel electrode 9a and the dummy pixel electrode 9b formed on the upper layer of the insulating layer 44 correspond to a third conductive layer.

[0056] 1-6. Effects of embodiment 1 FIG. 8 is an explanatory diagram of a comparative example to the first embodiment of the present invention. FIG. 9 is a diagram showing an example of the relationship between precharge and the output voltage VF of the temperature detection circuit 1. FIG. 10 is a graph showing the influence of the capacitance Cb parasitic to the temperature detection element 11 shown in FIG. 6 on the output voltage VF. In detail, FIG. 10 shows the relationship between the electrostatic capacitance of the parasitic capacitance Cb between the temperature detection element 11 and the common potential wiring 8a and the output voltage VF of the temperature detection circuit 1. In FIG. 10, the parasitic capacitance Cb is a capacitance parasitic between the relay part P1 including the electrode 6e1 of the diode D of the temperature detection element 11 and the common potential wiring 8a, and a capacitance parasitic between the relay part P2 including the electrode 6e2 and the common potential wiring 8a. Note that one pole of the diode D electrically connected to the electrode 6e1 is the same node as the electrode 6e1. Similarly, one pole of the diode D electrically connected to the electrode 6e2 is the same node as the electrode 6e2.

[0057] 8, the opening 8a0 is not formed in the common potential wiring 8a, and the temperature detection element 11 overlaps with the common potential wiring 8a in a plan view. Therefore, in the comparative example, a parasitic capacitance Cb (see FIG. 6) having a large electrostatic capacitance exists between the relay parts P1 and P2 of the diode D and the common potential wiring 8a. The parasitic capacitance Cb is largely influenced by the electrodes 6e1 and 6e2 arranged in a layer above the semiconductor layer 31h.

[0058] 7, in the electro-optical device 100 according to the first embodiment of the present invention, an opening 8a0 is formed in the common potential wiring 8a at a position overlapping with the temperature detection element 11 in a plan view. Therefore, the temperature detection element 11 does not overlap with the common potential wiring 8a in a plan view. Therefore, in the electro-optical device 100 according to the first embodiment of the present invention, there is no parasitic capacitance having a large electrostatic capacity between the electrodes 6e1, 6e2 of the diode D and the common potential wiring 8a, and therefore there is no parasitic capacitance Cb having a large electrostatic capacity between the relay parts P1, P2 and the common potential wiring 8a. Therefore, as described below, when spike noise occurs in the potential of the common potential wiring 8a due to precharging, in the comparative example, the potential change of the common potential wiring 8a affects the output voltage VF of the temperature detection element 11 via the parasitic capacitance Cb, whereas in the first embodiment, the above effect is unlikely to occur.

[0059] For example, when the driving current of the temperature detection circuit 1 including the temperature detection element 11 consisting of six diodes D is set to 100 nA, the following problem occurs. As shown in FIG. 9, when the precharge of the electro-optical device 100 is stopped at time t0 to t1, the output voltage VF of the temperature detection circuit 1 is approximately equal to the forward voltage expected in the six diodes D. Next, when the precharge is performed at time t1 to t2, the output voltage VF of the temperature detection circuit 1 drops by ΔVF1 and becomes saturated. When the precharge is stopped after time t2, the output voltage VF of the temperature detection circuit 1 returns to the output voltage VF at time t0 to t1. Moreover, this ΔVF1 is reduced when the conductive layer arranged above the temperature detection element 11 on the first substrate 10 and to which the common potential LCCOM is applied is made electrically floating.

[0060] Therefore, assuming parasitic capacitance Ca (see FIG. 6) and parasitic capacitance Cb (see FIG. 6), the diode D was modeled based on measurement data, and a circuit simulator was used to calculate the effect of a potential change in the common potential wiring 8a on the output voltage VF of the temperature detection circuit 1 via the parasitic capacitances Ca and Cb. In order to reduce the calculation time, the stabilizing capacitance 662 shown in FIG. 6 was set to 100 pF. Although the response time of the output voltage VF differs from that of the actual electro-optical device 100, it is sufficient to verify the behavior of the output voltage VF. The output voltage VF drops and saturates after the start of pre-charging, but a small voltage fluctuation synchronized with the pre-charging remains. Therefore, the average voltage for 0.01 sec, which is sufficiently longer than one horizontal period, was set as the output voltage VF. The calculation was performed assuming room temperature.

[0061] The potential of the common potential wiring 8a is basically a fixed potential as the common potential LCCOM, for example 7V, but the following noise is periodically superimposed with precharging. Here, one horizontal scanning period of 3μsec is close to one horizontal period when, for example, a WUXGA standard electro-optical panel is driven at 240 frames per second. The reason why the polarity of the noise voltage is negative is that spike noise toward the lower potential side than the common potential LCCOM occurs in the common potential wiring 8a. 1 horizontal scanning period = 3 μsec Noise voltage = -1.5V Noise voltage fall time = 100nsec Noise voltage rise time = 300nsec

[0062] As a result of the calculation, the parasitic capacitance Ca (see FIG. 6) was assumed to be 0.5 pF, but the effect on the output voltage VF of the temperature detection element 11 was small.

[0063] On the other hand, the calculation results shown in Fig. 10 were obtained as the relationship between the capacitance of the parasitic capacitance Cb and the output voltage VF. In Fig. 10, the calculation results of the output voltage VF of the temperature detection circuit 1 when the drive current IF is set to 100 nA, 200 nA, 400 nA, and 800 nA are shown by solid lines L100, L200, L400, and L800, respectively.

[0064] For example, a calculation result was obtained that indicates that if a parasitic capacitance Cb of 0.03 pF exists between the relay parts P1, P2, ... of the diode D and the common potential wiring 8a, the fluctuation ΔVF1 of the output voltage VF of the temperature detection element 11 may exceed 100 mV. If the output voltage VF fluctuates by 100 mV and the temperature detection element 11 has a sensitivity of approximately -10 mV / °C, the temperature measurement error will reach 10°C, making it difficult to control the temperature of the electro-optical device 100.

[0065] 10, it can be seen that reducing the parasitic capacitance Cb or increasing the drive current IF is effective in solving the above problem. Therefore, if the parasitic capacitance Cb between the relay parts P1, P2, ... of the diodes D electrically connected in series and the common potential wiring 8a is reduced as in this embodiment, it is possible to suppress the fluctuation of the output voltage VF, for example, as shown by ΔVF2 in FIG. 9. In other words, even if the potential of the common potential wiring 8a changes due to precharging, the fluctuation of the output voltage VF of the temperature detection circuit 1 is small, and therefore the temperature detection accuracy of the temperature detection element 11 can be improved.

[0066] Increasing the drive current IF makes it difficult for potential changes in the common potential wiring 8a to affect the output voltage VF of the temperature detection circuit 1, but increasing the drive current IF causes an increase in the forward voltage fluctuation ΔVF of the temperature detection element 11 relative to the drive current fluctuation ΔIF at the operating point due to the effect of series resistance, reducing the reliability of the detected temperature. Therefore, it is not preferable to simply increase the drive current of the diode D, as this makes the temperature detection circuit 1 difficult to use.

[0067] Moreover, when the driving current IF is increased, the output voltage VF, which is the operating point, rises, and the compliance voltage (operating point voltage upper limit) of the constant current circuit may not be maintained. For example, in a discharge-type constant current circuit using a transistor, an operational amplifier, a shunt regulator, etc., the upper limit of the operating point voltage for constant current operation when a 5V power supply is used is about 3.7V. From FIG. 10, for example, when the driving current IF is 400nA, the operating point voltage at room temperature is about 3.8V, so a constant current circuit driven by a 5V power supply cannot be used. In that case, the number of diodes in series is reduced in order to lower the operating point voltage, i.e., the output voltage VF, which causes a problem of reduced sensitivity to temperature of the temperature detection circuit 1. In addition, if the number of diodes in series is maintained, a new driving voltage source for the external circuit is required, which causes a problem of increased costs. From this viewpoint, in the first embodiment, since the configuration reduces the parasitic capacitance Cb, the potential change of the common potential wiring 8a is less likely to affect the output voltage VF of the temperature detection circuit 1 even if the driving current IF is not increased. Therefore, the temperature detection circuit 1 using the sensitive temperature detection element 11 can be driven by the temperature detection drive circuit 66 which can be constructed at low cost.

[0068] In this embodiment, since the island-shaped light-shielding layer 8e is provided in the opening 8a0, even when the opening 8a0 is provided, the incident light is prevented from becoming stray light and projecting the pattern of the diode D. Furthermore, by providing the island-shaped light-shielding layer 8e, the temperature of the electro-optic layer 50 can be easily transmitted to the temperature detection element 11.

[0069] 2. Embodiment 2 Fig. 11 is an explanatory diagram of an electro-optical device 100 according to a second embodiment of the present invention. Fig. 11 shows a planar configuration in the vicinity of a temperature detection element 11 of the electro-optical device 100 according to the second embodiment of the present invention. Fig. 12 is an explanatory diagram that typically shows a cross section of the temperature detection element 11 and the like shown in Fig. 11. Note that since the basic configuration of this embodiment is similar to that of the first embodiment, the same reference numerals are used for common parts and their description will be omitted.

[0070] As shown in FIG. 11 and FIG. 12, in this embodiment, a conductive layer 9b0 constituting a dummy pixel electrode 9b is arranged on the surface of the insulating layer 44 around the display area 10a of the first substrate 10. The conductive layer 9b0 has a shape in which, for example, a plurality of rectangular patterns similar to the pixel electrodes 9a are arranged and connected to each other at the center of the four sides constituting a rectangle. The conductive layer 9b0 overlaps with the temperature detection element 11 in a plan view. The conductive layer 9b0 is electrically connected to the common potential wiring 8a through a contact hole 44e penetrating the insulating layer 44. Therefore, a common potential LCCOM is applied to the conductive layer 9b0. According to this configuration, the voltage applied to the electro-optical layer 50 can be kept at 0V around the display area 10a, thereby suppressing deterioration of the electro-optical layer 50.

[0071] Here, the common potential wiring 8a has an opening 8a0 in a region overlapping the temperature detection element 11 in a plan view, as in the first embodiment. A light-shielding layer 8e overlapping the temperature detection element 11 in a plan view is provided inside the opening 8a0, and the light-shielding layer 8e is electrically floating. The conductive layer 9b0 is electrically connected to the common potential wiring 8a and overlaps the temperature detection element 11 in a plan view. Therefore, a parasitic capacitance exists between the conductive layer 9b0 and the relay parts P1 and P2 of the temperature detection element 11. However, as is clear from the comparative example of FIG. 8, the distance between the relay parts P1 and P2 of the temperature detection element 11 and the conductive layer 9b0 to which the common potential LCCOM is applied is increased by the thickness of the insulating layer 44. As a result, the parasitic capacitance formed between the relay parts P1 and P2 of the temperature detection element 11 and the conductive layer 9b0 can be reduced. Therefore, even if spike noise occurs in the common potential wiring 8a when precharging is performed, the fluctuation of the output voltage VF of the temperature detection circuit 1 can be suppressed. Therefore, the temperature detection accuracy in the electro-optical device 100 is high, and therefore the temperature control can be performed appropriately in the electro-optical device 100.

[0072] 2-1. Modification of the second embodiment Fig. 13 is an explanatory diagram of an electro-optical device 100 according to a modified example of the second embodiment of the present invention. Fig. 13 shows a schematic cross section of a temperature detection element 11 and other components of the electro-optical device 100 according to a modified example of the second embodiment of the present invention. Note that since the basic configuration of this embodiment is similar to that of the first and second embodiments, the same reference numerals are used for the common parts and the description thereof will be omitted.

[0073] 13, in this embodiment, a conductive layer 9b0 constituting dummy pixel electrodes 9b is disposed on the surface of an insulating layer 44 around the periphery of the display region 10a of the first substrate 10, as in the second embodiment. The conductive layer 9b0 has, for example, a shape in which a plurality of rectangular patterns similar to the pixel electrodes 9a are disposed and connected to each other at the centers of the four sides constituting the rectangle.

[0074] Here, between the electro-optical layer 50 and the common potential wiring 8a, insulating layers 44 and 45 are provided between the common potential wiring 8a and the conductive layer 9b0, and the relay electrode 7a is provided between the insulating layer 44 and the insulating layer 45. Therefore, the pixel electrode 9a is electrically connected to the relay electrode 7a via a contact hole 45d penetrating the insulating layer 45, and the relay electrode 7a is electrically connected to the relay electrode 8d via a contact hole 44d penetrating the insulating layer 44.

[0075] In addition, a conductive layer 7e0 constituting the wiring 7e is provided between the insulating layer 44 and the insulating layer 45. Therefore, the conductive layer 9b0 is electrically connected to the conductive layer 7e0 through a contact hole 45e penetrating the insulating layer 45, and the conductive layer 7e0 is electrically connected to the common potential wiring 8a through a contact hole 44e penetrating the insulating layer 44. Therefore, a common potential LCCOM is supplied to the dummy pixel electrode 9b and the wiring 7e. According to this configuration, the voltage applied to the electro-optical layer 50 can be kept at 0V around the display area 10a, so that deterioration of the electro-optical layer 50 can be suppressed. In addition, the wiring 7e can electrically connect the common potential wiring 8a electrically connected to the capacitance line in the display area 10a to the terminal 102g with low resistance, so that the effect of stabilizing the potential is also achieved.

[0076] Here, the common potential wiring 8a has an opening 8a0 in a region overlapping the temperature detection element 11 in a plan view, as in the first embodiment. A light-shielding layer 8e overlapping the temperature detection element 11 in a plan view is provided inside the opening 8a0, and the light-shielding layer 8e is in an electrically floating state. The conductive layer 7e0 is electrically connected to the common potential wiring 8a and overlaps the temperature detection element 11 in a plan view. Therefore, parasitic capacitance exists between the conductive layer 7e0 and the relay portion P1 and relay portion P2 of the temperature detection element 11. However, as is clear from the comparative example of FIG. 8, the distance between the relay portion P1 and relay portion P2 of the temperature detection element 11 and the conductive layer 7e0 to which the common potential LCCOM is applied is increased by the thickness of the insulating layer 44. As a result, the parasitic capacitance formed between the relay parts P1, P2 of the diode D of the temperature detection element 11 and the conductive layer 7e0 can be reduced. Therefore, even if spike noise occurs in the common potential wiring 8a when precharging is performed, the fluctuation of the output voltage VF of the temperature detection circuit 1 can be suppressed. Therefore, since the temperature detection accuracy in the electro-optical device 100 is high, the electro-optical device 100 can perform appropriate temperature control, and the same effects as those in the second embodiment can be achieved.

[0077] 3. Embodiment 3 Fig. 14 is an explanatory diagram of an electro-optical device 100 according to a third embodiment of the present invention. Fig. 14 shows a planar configuration in the vicinity of a temperature detection element 11 of the electro-optical device 100 according to the third embodiment of the present invention. Fig. 15 is a cross-sectional view of the temperature detection element 11 shown in Fig. 14. Note that the basic configuration of this embodiment is similar to that of the first and second embodiments, so the same reference numerals are used for common parts and their description will be omitted. Note that in Figs. 14 and 15, the number of diodes D electrically connected in series in the temperature detection element 11 is set to three for ease of understanding of the configuration.

[0078] As shown in FIG. 14 and FIG. 15, in the temperature detection element 11, when the direction in which the diodes D are arranged is defined as a first direction E and the direction perpendicular to the first direction E is defined as a second direction F, the semiconductor layer 31h constituting the diodes D is arranged in the first direction E, and adjacent diodes D are electrically connected by the electrode 6e1 of the relay portion P1 and the electrode 6e2 of the relay portion P2. In this embodiment, the first direction E is the Y direction, and the second direction F is the X direction. Note that one electrode of the diode D electrically connected to the electrode 6e1 is the same node as the electrode 6e1. Similarly, the other electrode of the diode D electrically connected to the electrode 6e2 is the same node as the electrode 6e2.

[0079] Here, when the pattern width, which is the dimension of the semiconductor layer 31h in the second direction F, is defined as W1, and the electrode width in the direction along the second direction F for the electrode 6e1 of the relay portion P1 and the electrode 6e2 of the relay portion P2 is defined as W2, the electrode width W2 has a portion narrower than the pattern width W1, as shown below. W1>W2

[0080] For example, when the pattern width W1 is 100 μm, the electrode width W2 is 5 μm. Since the current value flowing through the temperature detection element 11 is small, there is no problem even if the electrode width W2 is made small. The second diode D2 and the third diode D3 are configured similarly. Therefore, the area of ​​the electrodes 6e1 and 6e2 when viewed in a plane is small, so that the parallel plate-like parasitic capacitance formed between the relay parts P1 and P2 including the electrodes 6e1 and 6e2 and the common potential wiring 8a can be reduced. Therefore, even if spike noise occurs in the common potential wiring 8a when precharging is performed, the fluctuation of the output voltage VF of the temperature detection circuit 1 can be suppressed.

[0081] Here, the opening 8a0 of the common potential wiring 8a may be provided so as to expose all the diodes D as shown by the dotted line L1 in Fig. 14, or may be provided so as to mainly expose the relay parts P1 and P2 as shown by the dashed line L2. In the latter case, the anode wiring La electrically connected to the first diode D1 and the cathode wiring Lc electrically connected to the third diode D3 overlap with the common potential wiring 8a in a plan view. From the verification using the circuit model described above, it is the parasitic capacitance Cb between the relay parts P1 and P2 and the common potential wiring 8a that has a large effect on the fluctuation of the output voltage VF of the temperature detection circuit 1. Therefore, even if the anode wiring La or the cathode wiring Lc overlaps with the common potential wiring 8a, the effect is small.

[0082] Furthermore, in the verification using the circuit model described above, it was found that it is important to reduce the parasitic capacitance between the relay units P1, P2 and the noise source, so in this embodiment, the cathode wiring Lc, which is set to the ground potential GND, is extended in the first direction E along the arrangement direction of the diodes D. In other words, for the relay units P1, P2, the cathode wiring Lc may be used as a shield for wiring (not shown). In this case, if the cathode wiring Lc is a system separate from the ground potential GND wiring of the electro-optical panel 100p, the cathode wiring Lc becomes a constant potential wiring with low noise, and therefore has a high shielding effect.

[0083] Furthermore, for the relay parts P1 and P2, the constant potential wiring 6s supplying the low-level constant potential VSSY may be used as a shield for wiring (not shown) and may extend in the first direction E along the arrangement direction of the diodes D. Alternatively, the wiring supplying the high-level constant potential VDDY may be used as the shield.

[0084] 15, it is preferable to shorten the lengths L6e1, 6e2 of the electrodes 6e1, 6e2 by shortening the interval S0, which is the interval between the semiconductor layers 31h in the first direction E, within the range permitted by the design rules. By shortening the lengths L6e1, L6e2 of the electrodes 6e1, 6e2, the lengths LP1, LP2 of the relay portions P1, P2 are shortened. Therefore, the area of ​​the electrode 6e1 of the relay portion P1 and the area of ​​the electrode 6e2 of the relay portion P2 are reduced, and the parasitic capacitance Cb between the relay portions P1, P2 and the common potential wiring 8a can be reduced. Therefore, even if spike noise occurs in the common potential wiring 8a when precharging is performed, the fluctuation of the output voltage VF of the temperature detection circuit 1 can be suppressed.

[0085] 3-1. Modification 1 of the third embodiment FIG. 16 is an explanatory diagram of an electro-optical device 100 according to a first modified example of the third embodiment of the present invention. Fig. 16 shows a planar configuration near the temperature detection element 11 of an electro-optical device 100 according to a first modified example of the third embodiment of the present invention. Since the basic configuration of this embodiment is similar to that of the third embodiment, the same reference numerals are used for common parts and their description will be omitted. In Fig. 16, in order to make the configuration easier to understand, the number of diodes electrically connected in series in the temperature detection element 11 is set to three, and part of the common potential wiring 8a is not shown.

[0086] 16, when the direction in which the diodes D are arranged is defined as a first direction E and the direction perpendicular to the first direction E is defined as a second direction F, the semiconductor layers 31h constituting the diodes D are arranged in the first direction E, and adjacent diodes D are electrically connected by an electrode 6e1 of the relay portion P1 and an electrode 6e2 of the relay portion P2. In this embodiment, the first direction E is the Y direction, and the second direction F is the X direction.

[0087] Here, when the pattern width, which is the dimension of the semiconductor layer 31h in the second direction F, is W1, and the electrode width in the direction along the second direction F for the electrode 6e1 of the relay portion P1 and the electrode 6e2 of the relay portion P2 is W2, as in embodiment 3, the electrode width W2 has a portion narrower than the pattern width W1. W1>W2

[0088] For example, when the pattern width W1 is 100 μm, the electrode width W2 is 5 μm. Since the current value flowing through the temperature detection element 11 is small, there is no problem even if the electrode width W2 is made small. Therefore, the area of ​​the electrode 6e1 of the relay portion P1 and the area of ​​the electrode 6e2 of the relay portion P2 are reduced, and the parasitic capacitance Cb between the relay portions P1, P2 and the common potential wiring 8a can be reduced. Therefore, even if spike noise occurs in the common potential wiring 8a when precharging is performed, the fluctuation of the output voltage VF of the temperature detection circuit 1 can be suppressed.

[0089] Also, the interval S0 between the semiconductor layers 31h in the first direction E is shortened within the range permitted by the rules. More specifically, the selection circuit 101a of the data line driving circuit 101 includes a complementary transistor of an N-channel transistor 30n1 and a P-channel transistor 30p1. Similarly to the selection circuit 101a, the inverter circuit 104a of the scanning line driving circuit 104 also includes an N-channel transistor 30n2 and a P-channel transistor 30p2. Here, in order to shorten the circuit length, the interval S1 between the semiconductor layer constituting the N-channel transistor 30n1 and the semiconductor layer constituting the P-channel transistor 30p1, and the interval S2 between the semiconductor layer constituting the N-channel transistor 30n2 and the semiconductor layer constituting the P-channel transistor 30p2 are both set narrow. A similar measure can be taken in the inspection circuit 105. With this configuration, the peripheral circuit area outside the display area 10a of the electro-optical panel 100p can be made smaller, thereby making it possible to miniaturize the electro-optical panel 100p. As a result, the electro-optical panel 100p can be manufactured inexpensively. In this embodiment, as shown below, the spacing S0 in the diode D is set to be equal to or smaller than the spacing S1 between the N-channel transistor 30n1 and the P-channel transistor 30p1, and the spacing S2 between the N-channel transistor 30n2 and the P-channel transistor 30p2. S0 ≤ S1, S2

[0090] The design rule of the electro-optic panel 100p can be considered to be the minimum value (not shown) of the spacing S1, S2, or other spacing between the semiconductor layers of adjacent transistors of different conductivity types. Therefore, if that value is S3, its relationship with the spacing S0 is as follows: S0≦S3

[0091] The interval S3 is determined mainly by the impurity implantation mask pattern rule, because, for example, when forming a P-type region, it is necessary to create a mask pattern that sufficiently covers the N-type region and sufficiently separates it from the P-type region.

[0092] Therefore, for the temperature detection element 11, the semiconductor layer 31h in the first direction E is arranged at a distance S0 permitted by the design rule of the electro-optical panel 100p. As a result, the lengths L6e1 and L6e2 of the electrodes 6e1 and 6e2 shown in FIG. 15 can be shortened. Therefore, the area of ​​the electrode 6e1 of the relay portion P1 and the area of ​​the electrode 6e2 of the relay portion P2 are reduced, and the parasitic capacitance Cb between the relay portions P1 and P2 and the common potential wiring 8a can be reduced. Therefore, even if spike noise occurs in the common potential wiring 8a when precharging is performed, the fluctuation of the output voltage VF of the temperature detection circuit 1 can be suppressed.

[0093] The opening 8a0 of the common potential wiring 8a may be arranged so that all of the diodes D do not overlap with the common potential wiring 8a, as shown by the dotted line L1, or may be arranged so that the common potential wiring 8a does not overlap mainly with the relay portions P1 and P2, as shown by the dashed dotted line L2.

[0094] In this embodiment, the cathode wiring Lc extends in the first direction E between the temperature detection element 11 and the signal wiring 6d for supplying the start pulse SP, the signal wiring 6h for supplying the clock signal CLY, and the signal wiring 6f for supplying the output control signal ENBY, which extend along the first direction E. The cathode wiring Lc extends in the first direction E along the temperature detection element 11 on the opposite side of the signal wirings 6d, 6h, and 6f with respect to the temperature detection element 11 in the second direction F. Therefore, the cathode wiring Lc can be used as a shield against the AC signal wiring for the relay parts P1 and P2. In this case, if the cathode wiring Lc is provided in a system separate from the ground potential GND potential wiring of the electro-optical panel 100p, it is effective because the cathode wiring Lc becomes a constant potential wiring with low noise. It is preferable to extend the cathode wiring Lc in the first direction E on both sides of the temperature detection element 11. With this configuration, the capacitive coupling between the data line driving circuit 101 side and the relay portions P1, P2 can be suppressed, and the effect of the data line driving circuit 101 on the output voltage VF of the temperature detection circuit 1 can be reduced.

[0095] 3-2. Modification 2 of the third embodiment FIG. 17 is an explanatory diagram of an electro-optical device 100 according to a second modification of the third embodiment of the present invention. Fig. 17 shows a planar configuration near the temperature detection element 11 of an electro-optical device 100 according to Modification 2 of Embodiment 3 of the present invention. Since the basic configuration of this embodiment is similar to that of Embodiment 3, the same reference numerals are used for common parts and their description will be omitted. In Fig. 17, the number of diodes D electrically connected in series in the temperature detection element 11 is set to three for ease of understanding of the configuration.

[0096] 17, when the direction in which the diodes D are arranged is the first direction E and the direction perpendicular to the first direction E is the second direction F, the semiconductor layer 31h constituting the diodes D is arranged in the first direction E, and adjacent diodes D are electrically connected by the electrode 6e1 of the relay portion P1 and the electrode 6e2 of the relay portion P2. In this embodiment, the first direction E is the X direction, and the second direction F is the Y direction. Here, when the pattern width, which is the dimension of the semiconductor layer 31h in the second direction F, is W1, and the electrode width in the direction along the second direction F for the electrode 6e1 of the relay portion P1 and the electrode 6e2 of the relay portion P2 is W2, the electrode width W2 has a portion narrower than the pattern width W1, as in the third embodiment. W1>W2

[0097] Therefore, the area of ​​the electrode 6e1 included in the relay portion P1 and the area of ​​the electrode 6e2 included in the relay portion P2 are reduced, and the parasitic capacitance Cb between the relay portions P1, P2 and the common potential wiring 8a can be reduced. Therefore, even if spike noise occurs in the common potential wiring 8a when precharging is performed, the fluctuation of the output voltage VF of the temperature detection circuit 1 can be suppressed.

[0098] Moreover, an opening 8a0 is formed in the common potential wiring 8a, which overlaps with the temperature detection element 11 in a plan view. In this embodiment, the opening 8a0 reaches the end of the common potential wiring 8a, and the end of the common potential wiring 8a is an open end. In this manner, the opening 8a0 may be a notch provided on the side of the common potential wiring 8a. This configuration arises when it is desired to arrange the common potential wiring 8a as a low resistance wiring. Also, a part of the diode D constituting the temperature detection element 11 may be arranged outside a virtual line 8a1 that can be drawn in the extension direction of the side of the common potential wiring 8a in the opening 8a0. In this embodiment, the virtual line 8a1 can be drawn, for example, as a dashed line in FIG. 17.

[0099] In this embodiment, the signal wirings 6d, 6h, and 6f are arranged close to the temperature detection element 11. A signal having a voltage amplitude larger than the voltage fluctuation of the common potential wiring 8a due to precharging is applied to the signal wirings 6d, 6h, and 6f. The voltage amplitude of the signal is, for example, 15.5 V. In this embodiment, the signal wirings 6d, 6h, and 6f extend along the second direction F perpendicular to the first direction E in which the diodes D are arranged. Therefore, the signal wirings 6d, 6h, and 6f do not extend along the relay portions P1 and P2 of the diodes D. In other words, the relay portions P1 and P2 of the diodes D do not face the signal wirings 6d, 6h, and 6f in a plan view. Therefore, the parasitic capacitance between the signal wirings 6d, 6h, and 6f and the relay portions P1 and P2 can be reduced, suppressing fluctuations in the output voltage VF of the temperature detection circuit 1 caused by the signal wirings 6d, 6h, and 6f. In addition, since it is not necessary to arrange the shielded wire along the relay portions P1 and P2, the temperature detection element 11 can be more easily arranged.

[0100] In this embodiment, on the cathode side 11c of the temperature detection element 11, the cathode wiring Lc extends in the second direction F between the temperature detection element 11 and the signal wirings 6d, 6h, and 6f extending along the second direction F. Therefore, for the relay portions P1 and P2, the cathode wiring Lc can be used as a shield for the signal wirings 6d, 6h, and 6f.

[0101] 4. Embodiment 4 Fig. 18 is an explanatory diagram of precharging in an odd-numbered frame of the electro-optical device 100 according to the fourth embodiment of the present invention. Fig. 19 is an explanatory diagram of precharging in an even-numbered frame of the electro-optical device 100 according to the fourth embodiment of the present invention. Note that since the basic configuration of this embodiment is similar to that of the first embodiment, the same reference numerals are used for common parts and their description will be omitted.

[0102] In this embodiment, the multiple horizontal scanning periods include a first horizontal scanning period in which a precharge signal is supplied to a portion of the multiple data lines 6a, and a second horizontal scanning period in which a precharge signal is supplied to another portion of the multiple data lines 6a that is different from the portion of the multiple data lines 6a.

[0103] More specifically, the selection circuit 101a is composed of N-channel transistors as shown in Fig. 4. Then, as shown in Fig. 18, in the first horizontal scanning period Ha1 of the odd frame, during the precharge period tp, the control circuit 76 shown in Fig. 3 sets the odd-numbered selection signals SEL1, SEL3, SEL5, and SEL7 to the selection level, while setting the even-numbered selection signals SEL2, SEL4, SEL6, and SEL8 to the non-selection level. Therefore, the odd-numbered data lines 6a are precharged, and the even-numbered data lines 6a are not precharged.

[0104] 3 sets the odd-numbered selection signals SEL1, SEL3, SEL5, and SEL7 to the non-selection level, and sets the even-numbered selection signals SEL2, SEL4, SEL6, and SEL8 to the selection level during the precharge period tp in the second horizontal scanning period Ha2 of the subsequent odd-numbered frame. Thus, the even-numbered data lines 6a are precharged, and the odd-numbered data lines 6a are not precharged.

[0105] Also, as shown in FIG. 19, in the first horizontal scanning period Hb1 of the even frame, during the precharge period tp, the control circuit 76 shown in FIG. 3 sets the odd-numbered selection signals SEL1, SEL3, SEL5, and SEL7 to the non-selection level, while setting the even-numbered selection signals SEL2, SEL4, SEL6, and SEL8 to the selection level. Therefore, the even-numbered data lines 6a are precharged, and the odd-numbered data lines 6a are not precharged. In the second horizontal scanning period Hb2 of the following even frame, during the precharge period tp, the control circuit 76 shown in FIG. 3 sets the odd-numbered selection signals SEL1, SEL3, SEL5, and SEL7 to the selection level, while setting the even-numbered selection signals SEL2, SEL4, SEL6, and SEL8 to the non-selection level. Therefore, the odd-numbered data lines 6a are precharged, and the even-numbered data lines 6a are not precharged.

[0106] Therefore, since the number of data lines 6a to be precharged in one horizontal scanning period can be reduced, the peak voltage value of noise occurring in the common potential LCCOM can be reduced in the common potential wiring 8a. Qualitatively considered from the verification using a circuit model, it can be said that reducing the peak voltage of noise occurring in the common potential LCCOM is preferable for suppressing the fluctuation of the output voltage VF of the temperature detection circuit 1. That is, if all data lines 6a are precharged in one horizontal scanning period, the peak voltage of noise shown by the dashed lines in FIG. 18 and FIG. 19 is superimposed on the common potential LCCOM, but in this embodiment, since the number of data lines 6a to be precharged in one horizontal scanning period is reduced, the peak voltage of noise is suppressed to the peak voltage shown by the solid lines in FIG. 18 and FIG. 19. Therefore, even when precharging is performed, the fluctuation of the output voltage VF of the temperature detection circuit 1 can be suppressed.

[0107] 5. Embodiment 5 20 is an explanatory diagram of precharging of an electro-optical device 100 according to a fifth embodiment of the present invention. Since the basic configuration of this embodiment is similar to that of the first embodiment, the same reference numerals are used for common parts and their description will be omitted.

[0108] In this embodiment, the multiple horizontal scanning periods include a first horizontal scanning period in which a precharge signal is supplied to all of the multiple data lines 6a, and a second horizontal scanning period in which a precharge signal is not supplied to any of the multiple data lines 6a.

[0109] More specifically, as shown in FIG. 20, in the first horizontal scanning period Ha1 of an odd-numbered frame, all the data lines 6a are precharged, and in the subsequent second horizontal scanning period Ha2, none of the data lines 6a are precharged. Also, although not shown, in the first horizontal scanning period (corresponding to the first horizontal scanning period Ha1) of an even-numbered frame, none of the data lines 6a are precharged, and in the subsequent second horizontal scanning period (corresponding to the second horizontal scanning period Ha2), all of the data lines 6a are precharged. Therefore, in the common potential wiring 8a, it is possible to reduce the occurrence frequency of noise occurring in the common potential LCCOM. Considering qualitatively from the verification using a circuit model, it can be said that reducing the frequency of noise occurring in the common potential LCCOM is preferable for suppressing the fluctuation of the output voltage VF of the temperature detection circuit 1. That is, in the first horizontal scanning period in which all the data lines 6a are precharged, large noise is superimposed, but in the second horizontal scanning period in which all the data lines 6a are not precharged, no noise is superimposed. The dashed line indicates the fluctuation of the common potential LCCOM when all data lines 6a are precharged. If the frequency of noise occurring in the common potential LCCOM decreases, the fluctuation of the output voltage VF of the temperature detection circuit 1 is suppressed. Therefore, even when precharging is performed, the fluctuation of the output voltage VF from the temperature detection circuit 1 can be suppressed.

[0110] 6. Modifications of the Third, Fourth and Fifth Embodiments In the above-described third, fourth and fifth embodiments, in the electro-optical device 100, the opening 8a0 is provided in the common potential wiring 8a to reduce the parasitic capacitance Cb between the temperature detection element 11 and the common potential wiring 8a, and the fluctuation in the output voltage VF of the temperature detection circuit 1 is suppressed by the configuration of the method of performing precharge. However, the third, fourth and fifth embodiments may be applied to an electro-optical device 100 in which the common potential wiring 8a is not provided with the opening 8a0. That is, by applying the third, fourth and fifth embodiments to an electro-optical device 100 in which the common potential wiring 8a overlaps with the temperature detection element 11 in a planar view, the effect of noise on the temperature detection element 11 may be suppressed, and the fluctuation in the output voltage VF of the temperature detection circuit 1 may be suppressed.

[0111] 7. Another embodiment of the electro-optical device In the first, second, third, fourth, and fifth embodiments, the common potential wiring 8a is exemplified as the wiring, but the present invention can be applied to other wiring. For example, even in the ground potential GND wiring, a large noise may be superimposed similarly when precharging is performed, so the configurations of the first, second, third, fourth, and fifth embodiments may be applied to reduce the parasitic capacitance between the temperature detection element 11 and the ground potential GND wiring. The present invention may also be applied to wiring to which an AC signal is supplied. Precharging may be performed by replacing the inspection circuit 105 with a precharge circuit.

[0112] Furthermore, the electro-optical device 100 of the present invention is not limited to a liquid crystal device, and the present invention may be applied to electro-optical devices 100 other than liquid crystal devices, such as organic electroluminescence devices.

[0113] 8.Examples of electronic device configurations Fig. 21 is a block diagram showing a configuration example of a projection type display device 1000 to which the present invention is applied. Fig. 22 is an explanatory diagram of the light path shift element 110 shown in Fig. 21. Note that polarizing plates and the like are omitted from Fig. 21. The projection type display device 1000 shown in Fig. 21 is an example of an electronic device to which the present invention is applied, and includes an illumination device 190, a separation optical system 170, three electro-optical devices 100R, 100G, and 100B, and a projection optical system 160. Each of the electro-optical devices 100R, 100G, and 100B is composed of the electro-optical device 100 described with reference to Figs. 1 to 20.

[0114] The illumination device 190 is a white light source, and for example, a laser light source or a halogen lamp is used. The separation optical system 170 includes three mirrors 171, 172, and 175, and dichroic mirrors 173 and 174. The separation optical system 170 separates the white light emitted from the illumination device 190 into three primary colors of red R, green G, and blue B. Specifically, the dichroic mirror 174 transmits light in the red R wavelength range and reflects light in the green G and blue B wavelength ranges. The dichroic mirror 173 transmits light in the blue B wavelength range and reflects light in the green G wavelength range. The light corresponding to red R, green G, and blue B is guided to the electro-optical devices 100R, 100G, and 100B, respectively.

[0115] The light modulated by the electro-optical devices 100R, 100G, and 100B is incident on the dichroic prism 161 from three directions. The dichroic prism 161 constitutes a synthesis optical system in which red R, green G, and blue B images are synthesized. Therefore, the projection lens system 162 can enlarge and project the synthesized image output from the light path shift element 110 onto a projection target member such as a screen 180, thereby displaying a color image on the projection target member such as the screen 180.

[0116] At that time, the control unit 150 can correct the image signal supplied to the electro-optical devices 100R, 100G, and 100B based on the temperature detection result of the temperature detection circuit 1. Therefore, even if the environmental temperature or the like fluctuates, a high-quality projection image can be displayed. In addition, when a configuration is adopted in which the light path shift element 110 shown by the dashed line is provided in the projection optical system 160 on the side where the light is emitted from the dichroic prism 161, and the position where the projection pixel is viewed is shifted every predetermined period to increase the resolution, it is necessary to drive the liquid crystal layer at high speed. Even in this case, if a configuration is adopted in which the image signal supplied to the electro-optical devices 100R, 100G, and 100B is corrected based on the temperature detection result of the temperature detection circuit 1, or a configuration is adopted in which the temperature of the electro-optical panel 100p of the electro-optical devices 100R, 100G, and 100B is adjusted, the electro-optical layer 50 made of a liquid crystal layer can be driven at high speed.

[0117] The light path shift element 110 is an optical element that shifts the light emitted from the dichroic prism 161 in a predetermined direction as shown in Fig. 21. Fig. 22 illustrates an example in which the position of the projection pixel Pi, at which the light emitted from each pixel 100a of the electro-optical panel 100p is visually recognized, is shifted by the light path shift element 110 by a distance equivalent to 0.5 pixel pitch (=P / 2) on one side X1 in the X direction and by a distance equivalent to 0.5 pixel pitch (=P / 2) on one side Y1 in the Y direction. The light path shift element 110 includes a light-transmitting plate, and the actuator, under the command of the control unit 150, swings the light-transmitting plate around an axis extending in the first direction X and / or around an axis extending in the second direction Y, thereby shifting the light path of the light emitted from each pixel 100a of the electro-optical panel 100p to the light path LA and the light path LB.

[0118] 9. Other embodiments of electronic devices The projection display device may be configured to use an LED light source or the like that emits light of each color as the light source section, and supply each of the color lights emitted from the LED light source to a separate liquid crystal device.

[0119] An electronic device including the electro-optical device 100 to which the present invention is applied is not limited to the projection type display device 1000 of the above embodiment. For example, the present invention may be used in electronic devices such as a projection type HUD (head-up display) or a direct-view type HMD (head-mounted display), a personal computer, a digital still camera, and a liquid crystal television. [Explanation of symbols]

[0120] 1...temperature detection circuit, 3a...scanning line, 6a...data line, 6d, 6f, 6h...signal wiring, 6e1, 6e2...electrode, 6g, 7e...wiring, 7e0, 9b0...conductive layer, 8a...common potential wiring, 8a0...opening, 8a1...virtual line, 8e...light shielding layer, 9a...pixel electrode, 9b...dummy pixel electrode, 10...first substrate, 10a...display area, 11...temperature detection element, 11a...anode, 11c...cathode, 12...electrostatic protection circuit, 20...second substrate, 21... Common electrode, 29...partition, 30...pixel transistor, 30n1, 30n2...N-channel transistor, 30p1, 30p2...P-channel transistor, 31a, 31h...semiconductor layer, 50...electro-optical layer, 60...upper circuit, 65...image control circuit, 66...temperature detection drive circuit, 70...wiring board, 75...driver IC, 76...control circuit, 100, 100B, 100G, 100R...electro-optical device, 100a...pixel, 100p ...electro-optical panel, 101...data line driving circuit, 101a...selection circuit, 102a...anode terminal, 102c...cathode terminal, 104...scanning line driving circuit, 104a...inverter circuit, 106...precharge circuit, 110...light path shift element, 160...projection optical system, 161...dichroic prism, 162...projection lens system, 180...screen, 190...illumination device, 1000...projection type display device, D...diode, C1...first Capacitive element, C2...second capacitive element, D1...first diode, D2...second diode, D3...third diode, E...first direction, F...second direction, P1, P2...junction, R1...first resistive element, R2...second resistive element, R3...resistive element, W1...pattern width, W2...electrode width, Ca, Cb...parasitic capacitance, Ha1, Hb1...first horizontal scanning period, Ha2, Hb2...second horizontal scanning period, La...anode wiring, Lc...cathode wiring, Cn...connection node

Claims

1. Wiring having an opening outside the display area; a temperature detection element provided outside the display area and inside the opening in a plan view; An electro-optical device comprising:

2. 2. The electro-optical device according to claim 1, an island-shaped light-shielding layer, which is the same layer as the wiring and is spaced apart from the wiring, is provided inside the opening in a plan view;

3. 3. The electro-optical device according to claim 1, A plurality of data lines are provided in the display area; The electro-optical device according to claim 1, wherein each of the plurality of data lines has a portion that overlaps with the wiring in a plan view.

4. 4. The electro-optical device according to claim 3, The electro-optical device is characterized in that a constant potential is applied to the wiring.

5. 5. The electro-optical device according to claim 4, A liquid crystal layer; a conductive layer to which a common potential is applied between the liquid crystal layer and the wiring; An electro-optical device comprising:

6. 6. The electro-optical device according to claim 1, the temperature detection element includes a first diode, a second diode, and an electrode that electrically connects the first diode and the second diode in series; The first diode and the second diode are arranged along a first direction, An electro-optical device characterized in that the electrode has a portion whose width in a direction along a second direction intersecting the first direction is narrower than the width in the direction along the second direction of a semiconductor layer constituting the first diode and a semiconductor layer constituting the second diode.

7. 6. The electro-optical device according to claim 1, a complementary transistor having an N-channel transistor and a P-channel transistor outside the display area; the temperature detection element includes a first diode, a second diode, and an electrode that electrically connects the first diode and the second diode in series; an electro-optical device, characterized in that the distance between the semiconductor layer constituting the first diode and the semiconductor layer constituting the second diode is equal to or smaller than the distance between the semiconductor layer constituting the N-channel transistor and the semiconductor layer constituting the P-channel transistor.

8. 6. The electro-optical device according to claim 1, signal wiring to which an AC signal is supplied is provided outside the display area; the temperature detection element includes a first diode, a second diode, and an electrode that electrically connects the first diode and the second diode in series; The first diode and the second diode are arranged along a first direction, An electro-optical device, characterized in that a cathode wiring electrically connected to the first diode extends in a planar view between the first diode and the second diode and the signal wiring along the first direction.

9. 6. The electro-optical device according to claim 1, signal wiring to which an AC signal is supplied is provided outside the display area; the temperature detection element includes a first diode, a second diode, and an electrode that electrically connects the first diode and the second diode in series; The first diode and the second diode are arranged along a first direction, The electro-optical device, wherein the signal wiring extends along a second direction intersecting the first direction.

10. 6. The electro-optical device according to claim 3, A selection circuit for selecting the plurality of data lines; a control circuit that controls the selection circuit for each horizontal scanning period during a precharge period.

11. 11. The electro-optical device according to claim 10, An electro-optical device characterized in that the multiple horizontal scanning periods include a first horizontal scanning period in which a precharge signal is supplied to a portion of the multiple data lines, and a second horizontal scanning period in which the precharge signal is supplied to another portion of the multiple data lines that is different from the first portion.

12. 11. The electro-optical device according to claim 10, An electro-optical device characterized in that the multiple horizontal scanning periods include a first horizontal scanning period in which a precharge signal is supplied to all of the multiple data lines, and a second horizontal scanning period in which a precharge signal is not supplied to all of the multiple data lines.

13. An electronic device comprising the electro-optical device according to claim 1 .

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