JP2023056831A - Liquid crystal element, illumination device, vehicle lighting system, and method of manufacturing liquid crystal element - Google Patents

Abstract

To provide a liquid crystal element provided with a pretilt angle distribution without depending on the positions of pixel electrodes and the like.SOLUTION: A liquid crystal element disclosed herein comprises first and second substrates arranged to have one surface of each substrate face one surface of the other, a sealing material arranged substantially in an annular shape between the first substrate and the second substrate, and a liquid crystal layer disposed between the first substrate and the second substrate to be surrounded by the sealing material having an opening in plan view, where a pretilt angle of the liquid crystal layer varies depending on a distance from the opening in plan view.SELECTED DRAWING: Figure 9

Description

The present disclosure relates to a liquid crystal element, a lighting device, a vehicle lighting system, and a method for manufacturing a liquid crystal element.

Japanese Patent Application Laid-Open No. 2002-357830 (Patent Document 1) discloses a pair of substrates facing each other with a predetermined cell gap, a vertical alignment film formed between the pair of substrates, and a sealing device between the vertical alignment films. a liquid crystal layer having negative dielectric anisotropy, and an alignment control structure disposed on at least one of a pair of substrates for controlling the alignment direction of the entire liquid crystal molecules in the liquid crystal layer when a voltage is applied. and a cured product with a liquid crystal skeleton provided in the liquid crystal layer to tilt the liquid crystal molecules. In this liquid crystal display device, a region with a small pretilt angle and a region with a large pretilt angle are provided in the pixel electrode through a complicated process such as exposing a monomer using a photomask during manufacturing.

Japanese Patent Application Laid-Open No. 2002-357830

It is an object of a specific aspect of the present disclosure to provide a liquid crystal element provided with a pretilt angle distribution independent of the position of a pixel electrode or the like, or an apparatus including the same.

[1] A liquid crystal element according to one aspect of the present disclosure includes (a) a first substrate and a second substrate arranged so that one surface sides thereof face each other, and (b) the first substrate and the second substrate. (c) a liquid crystal layer surrounded by the sealing material between the first substrate and the second substrate; (d) the sealing material has one aperture in plan view, and (e) a liquid crystal element in which the pretilt angle in the liquid crystal layer varies depending on the distance from the aperture in plan view.
[2] A lighting device according to one aspect of the present disclosure includes (a) the liquid crystal element of [1], (b) a pair of polarizing elements arranged to face each other with the liquid crystal element interposed therebetween, and (c) the liquid crystal and a light source for causing light to enter the element.
[3] A vehicle lighting system according to one aspect of the present disclosure includes: (a) a vehicle lighting device configured using the lighting device of [2]; The vehicle lighting system includes a controller that applies a driving voltage to the liquid crystal element of the lighting device, and (c) a lens that collects the light that has passed through the liquid crystal element and projects the light onto the periphery of the vehicle.
[4] A method of manufacturing a liquid crystal element according to one aspect of the present disclosure includes: (a) preparing a first substrate and a second substrate each having a conductive film on one surface side; forming a vertical alignment film on one surface of each of the second substrates; (c) performing a rubbing process on the vertical alignment films of each of the first substrate and the second substrate; (e) forming a substantially annular sealing material having one opening in a plan view on one surface side of the first substrate or the second substrate; (f) injecting a liquid crystal material containing a monomer that polymerizes by light irradiation into a space between the first substrate and the second substrate and surrounded by the sealing material through the opening; (g) applying a voltage to the liquid crystal material using the conductive films of each of the first substrate and the second substrate, and applying a voltage to the liquid crystal material through the first substrate and/or the second substrate; A method for manufacturing a liquid crystal device, comprising polymerizing the monomer by irradiating with light.

According to the above configuration, it is possible to provide a liquid crystal element having a pretilt angle distribution independent of the position of the pixel electrode or a device including the same. Further, according to the above configuration, it is possible to manufacture a liquid crystal element having a distribution of pretilt angles regardless of the positions of the pixel electrodes or the like.

FIGS. 1A and 1B are schematic plan views showing configurations of liquid crystal elements used in experiments. FIG. 1C is a schematic cross-sectional view showing the structure of a liquid crystal element. FIG. 2A is a diagram showing the measurement results of the pretilt angle distribution in each liquid crystal element. FIG. 2B is a diagram showing the relationship between the distance from the injection port and the pretilt angle, normalized with the distance at which a pretilt angle of 86° or less is obtained being 100 (relative value). FIG. 3 is a diagram showing the relationship between monomer concentration and pretilt angle. FIG. 4A is a diagram showing the results of measuring the response performance of the liquid crystal element with respect to the pretilt angle. FIG. 4B is a diagram showing the relationship between applied voltage and transmittance for two pretilt angles. FIGS. 5A and 5B are diagrams showing changes in transmittance with respect to elapsed time from voltage application when the pretilt angle is 87°. FIG. 6 is a diagram showing the relationship between the relative distance (normalized distance) from the injection port and the pretilt angle in the liquid crystal element. FIG. 7 is a schematic perspective view showing the configuration of the vehicle lamp according to one embodiment. FIG. 8 is a block diagram showing a configuration example of a vehicle lighting system including the vehicle lighting shown in FIG. FIG. 9 is a schematic plan view for explaining the pixel configuration of the liquid crystal element. 10 is a diagram for explaining the relative distance from the injection port in the liquid crystal element shown in FIG. 9. FIG. FIG. 11 is a schematic cross-sectional view showing a configuration example of a liquid crystal element. FIG. 12 is a schematic plan view showing the configuration of the liquid crystal element. FIG. 13 is an image diagram showing a specific example of illumination light generated by the vehicle lamp system. FIG. 14 is a diagram showing the relationship between the voltage applied to the liquid crystal layer and the pretilt angle during polymerization.

First, the contents of the considerations that the inventors made until they created the liquid crystal element or the like according to the present disclosure will be described. Embodiments of a vehicle lamp, which is an example of a lighting device, and a vehicle lamp system including the vehicle lamp will be described.

In general, a liquid crystal element used as a display is required to have uniform transmittance-voltage characteristics (VT characteristics) and response characteristics. Therefore, it is desirable that the alignment state of the liquid crystal layer of the liquid crystal element is uniform, except when the alignment state within the pixel is divided to achieve a wide viewing angle. Among the alignment states of the liquid crystal layer, the pretilt angle is important. If the pretilt angle differs depending on the position in the liquid crystal element, it affects the VT characteristics, such as causing a difference in the threshold voltage or changing the sharpness, thereby affecting the display quality. It is not preferable because it becomes non-uniform. Liquid crystal elements used as optical elements for non-display applications are also required to have uniform VT characteristics and response characteristics in many cases.

However, in some special applications, it may be preferable that the alignment state differs depending on the position in the liquid crystal element. For example, consider a case where a liquid crystal element is used to configure a vehicle lamp that can freely control the light emitted to the front of the vehicle. In this case, the conditions of the illuminating light required for the vehicular lamp differ depending on the location where the illuminating light is projected, so the characteristics required for the liquid crystal element as the shutter element may differ depending on the position within the liquid crystal element. For example, in a liquid crystal element, a high-speed response is particularly required in a region used for forming a high beam (high beam forming region) because it is necessary to frequently switch the transmittance. On the other hand, for example, in a region used to form a low beam (low beam forming region), the transmittance is switched less frequently, so a higher transmittance is required than a high-speed response. In addition, in areas around areas used for high beams and low beams, the transmittance is hardly switched, and high light shielding properties (glare suppression) are required.

Therefore, the pretilt angle θp is set relatively small in the high-beam formation area where switching is frequent and in the light-condensing area near the center to improve responsiveness. It is considered preferable to set the pretilt angle .theta.p to a large value close to 90.degree. In this specification, the term “pretilt angle” refers to an average tilt angle of liquid crystal molecules defined by setting the direction perpendicular to the layer thickness direction of the liquid crystal layer as a reference (0°) and the layer thickness direction as 90°. say.

In general, changing the pretilt angle requires changing the alignment conditions. A typical method is a photo-alignment method. However, in the photo-alignment method, the alignment control force of the resulting alignment film is weak, and the alignment treatment takes a long time. On the other hand, the rubbing method is an excellent alignment treatment method in which an alignment film having a strong alignment control force can be obtained and the alignment treatment can be performed in a short time. However, it is difficult to change the alignment state depending on the position in the liquid crystal element. be.

Therefore, the inventor of the present application uses a vertical alignment film and combines a rubbing method, a polymer stabilization (polymer stabilization) technology, and a vacuum injection method, so that a liquid crystal element can be obtained without using a complicated process or an expensive device. It was conceived that the desired pretilt angle distribution could be realized by It should be noted that the vertical alignment film is desired to have both light resistance and a good pretilt angle, but when light resistance is emphasized, it may be difficult to give a pretilt angle of more than 90° by rubbing alone. be. In this regard, a combination of polymer stabilization techniques makes it possible to impart a slanted pretilt angle.

Specifically, the polymer stabilization technology used in the present disclosure is a liquid crystal material to which a small amount (for example, 0.5 wt % or less) of a monomer (also referred to as a reactive mesogenic (RM) agent) is added to a liquid crystal cell (before injecting the liquid crystal material). liquid crystal element) to form a liquid crystal layer, and by applying a voltage to this liquid crystal layer and irradiating it with ultraviolet rays (UV), the monomer polymerizes and stabilizes the alignment state of the liquid crystal layer. .

Here, according to the studies of the inventors of the present application, the monomer has a property of being localized (adsorbed) near the interface between the liquid crystal layer and the substrate rather than in the bulk of the liquid crystal layer. Although it depends on the monomer material and alignment film material, the monomer is generally molecularly designed so that it can be easily adsorbed to the alignment film interface. When a liquid crystal material to which a monomer is added is injected by a vacuum injection method through an injection port provided in a sealing material, the injection progresses while the monomer is adsorbed to the interface in order from a position closer to the injection port. Therefore, the molecular weight of the monomer adsorbed on the alignment film interface near the injection port is large, and the molecular weight of the monomer adsorbed on the alignment film interface decreases as the distance from the injection port increases.

Further, according to experiments by the inventors of the present application, the larger the molecular weight of the monomer at the interface of the liquid crystal layer, the smaller the pretilt angle when the monomer is polymerized (polymerized) by UV irradiation while voltage is applied. have understood. For example, even if the pretilt angle given only by the rubbing treatment is about 89.5° (approximately 90°), by polymerizing the monomers while applying a voltage to the liquid crystal layer, the pretilt angle is about 84° to 88°, for example. It is possible to obtain a pretilt angle of It was also found that the obtained pretilt angle depends on the distance from the injection port (the amount of monomer adsorbed on the interface), and a more inclined pretilt angle (smaller pretilt angle) can be obtained near the injection port. Next, experimental results regarding the relationship between the distance from the inlet and the pretilt angle will be described.

FIGS. 1A and 1B are schematic plan views showing configurations of liquid crystal elements used in experiments. FIG. 1C is a schematic cross-sectional view showing the structure of a liquid crystal element. The liquid crystal element 500A shown in FIG. 1A and the liquid crystal element 500B shown in FIG. 1B have the same structure except that the length in the long side direction is different. Specifically, each liquid crystal element 500A, 500B includes a pair of substrates 505, 506, a liquid crystal layer 507 disposed between the substrates 505, 506, and a liquid crystal layer 507 between the substrates 505, 506 for sealing the liquid crystal layer 507. A sealing material 501 provided between, a plurality of pixel electrodes 502 provided on one substrate 505, a common electrode 504 provided on the other substrate 506 and arranged opposite to each pixel electrode 502, and a substrate 505 A vertical alignment film 508 provided on one surface side and a vertical alignment film 509 provided on one surface side of the substrate 506 are provided.

The sealing material 501 is provided so as to surround the liquid crystal layer 507, and has an injection port 503, which is an opening for injecting a liquid crystal material when forming the liquid crystal layer 507, on one side on the left side in the drawing.

Each pixel electrode 502 has a square shape in plan view, and each side has a size of 15 mm. Each pixel electrode 502 is arranged at a pitch of 25 mm. Here, the liquid crystal element 500A in FIG. 1A has a long side length of approximately 125 mm. The liquid crystal element 500B in FIG. 1B has a long side length of approximately 75 mm. In the following description, the liquid crystal element 500A may be called a "long cell" and the liquid crystal element 500B may be called a "middle cell".

Here, a method for manufacturing the liquid crystal elements 500A and 500B will be described with reference to FIG. 1(C).
First, a substrate (first substrate) 505 having a pixel electrode (conductive film) 502 on one side and a substrate (second substrate) 506 having a common electrode (conductive film) 504 on one side are prepared. Vertical alignment films (first/second vertical alignment films) 508 and 509 are formed on one side of 506 .
Then, the vertical alignment films 508 and 509 of the substrates 505 and 506 are subjected to rubbing treatment.
Next, on one surface side of the substrate 505 (or substrate 506), a substantially annular sealing material 501 having one inlet (opening) 503 in plan view is formed.
Next, the substrates 505 and 506 are attached so that one surface sides thereof face each other, and a liquid crystal material is injected from the injection port 503 into the space surrounded by the sealing material 501 between the substrates 505 and 506 . At this time, as the liquid crystal material, a liquid crystal material containing a monomer that polymerizes by light irradiation is used. After injection, the injection port 503 is sealed with a sealing material.
Next, as shown in the figure, while applying a voltage (for example, a voltage of 10 V) to the liquid crystal material using each pixel electrode 502 of the substrate 505 and the common electrode 504 of the substrate 506, the liquid crystal material is exposed through the substrate 506 (or the substrate 505). , the monomer contained in the liquid crystal material is polymerized by irradiating light (in this case, ultraviolet irradiation).
As described above, the liquid crystal elements 500A and 500B are obtained.

FIG. 2A is a diagram showing the measurement results of the pretilt angle distribution in each of the liquid crystal elements 500A and 500B. The pretilt angle at each position was measured at three points and the average value was obtained. As shown in the figure, the shorter the distance from the injection port 503 (the closer to the injection port 503), the smaller the pretilt angle. That is, it can be seen that a more inclined pretilt angle can be provided. Looking at the measurement results in detail, it can be seen that the pretilt angle increases as the distance from the injection port 503 increases.

In this measurement result, the pretilt angle is 89° or more at the position farthest from the injection port 503 (position of 120 mm). This value of the pretilt angle is not preferable in that the response when voltage is applied (when turned on) is relatively slow (for example, 1 second or longer). On the other hand, since the transmittance is low when no voltage is applied (when turned off), the pretilt angle is preferable for the peripheral region where higher light shielding properties (when turned off) and higher transmittance (when turned on) are required than responsiveness as described above. is. Therefore, in the case of the liquid crystal element 500A having a long side length of 125 mm, it is desirable to arrange the area at a distance of 120 mm or more from the injection port 503 in the peripheral area (background area). In addition, when no electrode is provided in the peripheral region, the polymer cannot be stabilized, and the pretilt angle in that case is about 89.6°, but there is no practical problem.

Looking at the pretilt angles of the liquid crystal element 500A (long cell) and the liquid crystal element 500B (middle cell) in more detail, it can be seen that the values of the pretilt angle with respect to the distance from the injection port 503 are subtly different. Specifically, compared to the liquid crystal element 500A (long cell), the liquid crystal element 500B (middle cell) tends to have a larger pretilt angle with respect to the distance from the injection port 503, and the difference increases as the distance from the injection port 503 increases. It can be seen that there is a trend

As described above, the liquid crystal material used in this experiment contains a monomer (RM agent), and it is considered that this monomer has the property of adsorbing to the interface. When the liquid crystal material is injected using the vacuum injection method, the monomers in the liquid crystal material injected from the injection port 503 flow between the substrates 505 and 506 while being adsorbed to the interface in order. Therefore, more monomers are adsorbed on the alignment film interface near the injection port 503 , and less monomers are adsorbed on the alignment film interface as the distance from the injection port 503 increases.

When the polymer stabilization treatment is performed, it becomes possible to provide a pretilt angle according to the voltage applied at that time, but the pretilt angle tends to depend on the amount of monomer adsorbed on the interface. Specifically, the larger the amount of adsorbed monomer, the smaller the pretilt angle, and the smaller the amount, the larger the pretilt angle. As can be seen from FIG. 2A, the monomer adsorption amount does not simply depend on the distance from the inlet 503, but also depends on the overall length of the liquid crystal elements 500A and 500B to be injected. In the large liquid crystal element 500A, the possibility of monomer adsorption increases while the liquid crystal material flows to a position far from the injection port 503, and as a result, it is possible to provide a small pretilt angle to the far side.

FIG. 2B is a diagram showing the relationship between the distance from the injection port and the pretilt angle, normalized with the distance at which a pretilt angle of 86° or less is obtained being 100 (relative value). Although there are some variations, it can be seen that there is no dependence on the length of the long side of the liquid crystal element when it is normalized, and almost the same pretilt angle is exhibited even if the length of the long side is different. Also, it can be seen that the pretilt angle increases linearly when the ratio of the distance from the injection port to the farthest position from the injection port is up to about 80%. This indicates that it is possible to manufacture a liquid crystal element having a desired pretilt angle distribution by arranging the electrode pattern in consideration of the size (length) of the liquid crystal element and the position of the injection port. .

As described above, in the liquid crystal element 500A, the amount of monomer interfacially adsorbed at a position 120 mm or more from the injection port 503 is small and the pretilt angle is large. ), it is considered that the relationship between the distance from the injection port and the pretilt angle is established as a ratio. Here, according to FIG. 2A, in the liquid crystal element 500A, the pretilt angle is 89° in the region where the ratio of the distance from the injection port 503 to the length of the long side is 96%, that is, at a distance of 120 mm from the injection port. It has been confirmed that Applying this ratio to the liquid crystal element 500B (middle cell), it is estimated that the pretilt angle is 89° or more in a region where the distance from the injection port 503 is 72 mm or more. Providing a non-operating region in the display area is not positively adopted in a liquid crystal element for display purposes, but in some cases it is rather preferable in a liquid crystal element for purposes such as the present embodiment.

FIG. 3 is a diagram showing the relationship between monomer concentration and pretilt angle. Here, with respect to the monomer concentration, a predetermined concentration is defined as a reference concentration 1, and the concentration is variably set to 1/2 of the reference, 1/4 of the reference, 1/8 of the reference, and 1/16 of the reference. The result of measuring the pretilt angle using the liquid crystal element manufactured by the method shown in 1(C) is shown. As shown in FIG. 3, the pretilt angle increases almost linearly as the monomer concentration decreases. Therefore, it can be said that the pretilt angle can be controlled by the monomer concentration, and the monomer concentration can be controlled by the distance from the inlet (and its relative value).

FIG. 4A is a diagram showing the results of measuring the response performance of the liquid crystal element with respect to the pretilt angle. Here, a liquid crystal element manufactured in the same manner as the above liquid crystal element 500A is used, pixel electrodes are provided at positions corresponding to respective pretilt angles, and an ON voltage (10 V) is applied between the pixel electrodes and the common electrode at the positions. ) was applied, the change in transmittance over time was measured. A liquid crystal material having a refractive index anisotropy Δn of 0.1 to 0.13 was used for the liquid crystal layer of the liquid crystal element.

In the liquid crystal element with a pretilt angle of 86° to 88°, a transmittance bound is observed in the transient response. This is considered to be due to the transient alignment disturbance caused by the fact that when the difference between the pretilt angle and the electric field direction (90°) is small, it is difficult to uniformly tilt the liquid crystal molecules when the alignment is changed by the voltage.

Under the condition where the difference between the pretilt angle and the electric field direction is large (pretilt angle smaller than 86°), the tilt direction of the liquid crystal molecules tends to be uniform with respect to the electric field direction, and alignment disorder does not occur even in a transient state, and the alignment is not disturbed for 20 msec. , the transmittance changes to the desired value (90% or more of the saturated transmittance) in a relatively short time.

On the other hand, it has been found that if the pretilt angle is too small, light leakage is likely to occur when the voltage is turned off. FIG. 4B is a diagram showing the relationship between applied voltage and transmittance for two pretilt angles. As shown in the figure, when the pretilt angle is 84°, the transmittance when the voltage is off (when the voltage is equal to or lower than the threshold) is slightly higher than when the pretilt angle is 87°. This is the result of measurement in the direction normal to the substrate surface of the liquid crystal element, but the difference becomes more pronounced when the measurement is made in the oblique direction of the substrate surface. Therefore, it can be seen that a pretilt angle of around 87° is preferable in order to further reduce the transmittance when the voltage is off.

Considering these response performances, in the liquid crystal element used as the shutter element of the vehicle lamp, a pretilt angle of about 84° is preferable in the high beam formation region where the transmittance needs to be frequently switched, and it is preferable for high-speed response. It can be said that a pretilt angle of about 87°, which is a larger value than the above 84°, is preferable in a low-beam forming region where a high light shielding property is required.

It should be noted that there is a possibility that the transmittance bound in the transient response when the pretilt angle is set to a large value can be improved by adjusting the magnitude of the applied voltage. For example, when the pretilt angle is 87°, when a relatively high voltage (here, 10 V) is applied, the transmittance bounces as shown in FIG. For example, when a voltage of 5 V) is applied, no transmittance bound is observed as shown in FIG. 5(B).

FIG. 6 is a diagram showing the relationship between the relative distance (normalized distance) from the injection port and the pretilt angle in the liquid crystal element. Here, the distribution of pretilt angles was obtained based on the results of the liquid crystal element 500A (long cell) described above. The relative distance (normalized distance) is a relative distance when the linear distance from the injection port to the sealing material is taken as 100%. The relationship between the relative distance from the inlet and the pretilt angle can be classified into, for example, the following four regions.

Region A is a region where the relative distance from the inlet is within 50% (pretilt angle is less than 84.5°). This region A is a region suitable for a portion where the transmittance is frequently switched as described above. Region B is a region where the relative distance from the inlet is 50% or more and less than 80% (pretilt angle is 84.5° or more and less than 85.5°). This region B is a region suitable for a portion where the transmittance is frequently switched. Region C is a region where the relative distance from the inlet is 80% or more and less than 96% (pretilt angle is 85.5° or more and less than 89°). This region C is a region suitable for a portion where there is little change in transmittance and high light shielding properties are required. Region D is a region where the relative distance from the injection port is 96% or more (pretilt angle of 89° or more). This region D is a region suitable for a portion such as a peripheral region, a background portion, etc., in which the frequency of transmittance switching is extremely low, or a portion that does not need to be switched. Region B can be said to be the most preferable region in terms of having both responsiveness and light shielding properties.

Next, an embodiment of a liquid crystal element, a vehicle lamp or a vehicle lamp system including the liquid crystal element configured based on the above considerations will be described.

FIG. 7 is a schematic perspective view showing the configuration of the vehicle lamp according to one embodiment. The illustrated vehicle lamp 100 includes a light source 10 having a light emitting element such as an LED (light emitting diode), a liquid crystal element 11 arranged so that the light emitted from the light source 10 is incident thereon, and driving the liquid crystal element 11. A driver 12 that generates a voltage, a pair of polarizing elements (polarizing plates) 13a and 13b arranged opposite to each other with the liquid crystal element 11 interposed therebetween, and a light image formed by the liquid crystal element 11 and the pair of polarizing plates 13a and 13b. and a projection lens 14 for projecting forward of the vehicle. Although the illustrated example shows the case where the driver 12 is directly mounted on the substrate edge of the liquid crystal element 11, the liquid crystal element 11 and the driver 12 may be arranged separately.

Light source 10 emits light under control of a controller. The light source 10 includes, for example, several light emitting elements such as white LEDs (Light Emitting Diodes) and a driving circuit. Note that the configuration of the light source 10 is not limited to this. For example, as the light source 10, it is possible to use a laser element, a light bulb, a discharge lamp, or other light sources generally used in vehicle lamp units.

The liquid crystal element 11 is arranged near the focal point of the projection lens 14 . Also, although not shown, an appropriate optical system may be used for causing the light emitted from the light source 10 to enter the liquid crystal element 11 . The optical system in this case may be configured as a condensing means such as a reflector or condensing lens for condensing the light emitted from the light source 10 onto a predetermined portion of the liquid crystal element 11 . In the case of the light source 10 using an LED, light is generally incident at an angle of ±30° or more even if the light is arranged to converge on the liquid crystal element 11 at as narrow an angle as possible. Also, the optical system may be configured to allow light having an illuminance distribution to enter the plane of the liquid crystal element 11 . Further, the vehicle lamp 100 can also include an optical compensation plate between the liquid crystal element 11 and the polarizing plate 13b. By arranging the optical compensator, it is possible to compensate for the phase difference of the light transmitted through the liquid crystal element 11 and increase the degree of polarization. The optical compensator can suppress light leakage when light is blocked by the liquid crystal element 11 .

In the vehicle lamp 100 shown in FIG. 7, the liquid crystal element 11 has a plurality of pixels (segment regions) each capable of independently modulating light by voltage control. The vehicular lamp 100 of this embodiment applies a voltage to each pixel of the liquid crystal element 11 according to the position of, for example, an oncoming vehicle or a preceding vehicle (hereinafter referred to as "front vehicle") existing in front of the own vehicle. By controlling, it is possible to set a dimming range 22 according to the position of an oncoming vehicle or the like, and to generate illumination light having a light distribution pattern in which the other areas are set to light illumination ranges 20 and 21 .

FIG. 8 is a block diagram showing a configuration example of a vehicle lighting system including the vehicle lighting shown in FIG. Here, it is assumed that two vehicle lamps are used as headlights and arranged in the front part of the vehicle. The illustrated vehicle lamp system 1 includes vehicle lamps 100L and 100R, a light distribution control unit 101, a forward monitoring unit 102, an in-vehicle camera 103, a radar 104, a vehicle speed sensor 105, a steering angle sensor 106, a GPS sensor 107, and a switch 108. is composed of Vehicle lamps 100L and 100R, a forward monitoring unit 102, a vehicle speed sensor 105, a steering angle sensor 106, a GPS sensor 107, and a switch 108 are connected to the light distribution control unit 101. FIG. A light distribution control unit 101 , an in-vehicle camera 103 , a radar 104 and a vehicle speed sensor 105 are connected to the forward monitoring unit 102 . A "controller" includes at least the light distribution control unit 101, the forward monitoring unit 102, and the driver 12 described above.

The light distribution control unit 101 is connected to each of the vehicle lamps 100L and 100R, and determines the attributes (oncoming vehicle, preceding vehicle, reflector, road lighting, etc.) of roadside bright objects sent from the forward monitoring unit 102 and their positions. Based on the vehicle speed (front, side, etc.) and the vehicle speed detected by the vehicle speed sensor 105, a control signal for realizing the above-described light distribution pattern is generated and supplied to the driver 12 of each vehicle lamp 100L, 100R. do. In addition, the light distribution control unit 101 controls turning on/off of the light sources 10 of the vehicle lamps 100L and 100R in accordance with the operation state of the switch 108 . The light distribution control unit 101 can also use the steering angle of the vehicle detected by the steering angle sensor 106 and the current position of the vehicle detected by the GPS sensor 107 when setting the light distribution pattern. . The light distribution control unit 101 includes, for example, a CPU, ROM, RAM, etc., and can be configured using a computer capable of executing predetermined information processing by executing an operation program. .

The forward monitoring unit 102 performs image processing on the imaged data acquired from the vehicle-mounted camera 103 to detect forward vehicles, other bright objects on the road, lane markings, etc., and determine their attributes and positions. data to the light distribution control unit 101 . The forward monitoring unit 102 can also detect the position of a forward vehicle or the like based on object detection data acquired from the radar 104 . This forward monitoring unit 102 can be configured using, for example, a dedicated processor specifically designed for this control. Note that the forward monitoring unit 102 and the vehicle-mounted camera 103 may be configured integrally.

FIG. 9 is a schematic plan view for explaining the pixel configuration of the liquid crystal element. The liquid crystal element 11 includes a plurality of pixels (segment regions), which are arranged within an effective display region, which is an inner region surrounded by the sealing material 15 in plan view. In the illustrated liquid crystal element, each of rectangular regions and triangular regions of various sizes corresponds to a pixel. In the drawing, some pixels are shown with reference numerals as an example. Reference symbol R shown in the drawing indicates the axis of symmetry of the sealing material 15 . The seal member 15 is formed in a substantially rectangular shape that is symmetrical with respect to the axis of symmetry R in a plan view. The shape of the sealing material 15 is not limited to this, and may be square, for example. Further, in the present embodiment, a pixel electrode (described later) forming each pixel has substantially the same shape as each pixel, and is provided in a shape substantially symmetrical with respect to the symmetry axis R of the sealing material 15 .

For example, the pixel 30a is a small-area, square-shaped pixel that is small in both the X-direction length and the Y-direction length. The pixel 30b is a trapezoidal pixel whose X-direction length is longer than that of the pixel 30a and whose Y-direction length is slightly longer than that of the pixel 30a. The pixel 30c is a vertically long rectangular pixel with a small length in the X direction and a relatively large length in the Y direction. The pixel 30d is a vertically long rectangular pixel having a smaller length in the X direction than the pixel 30b. The pixel 30e is a triangular pixel having a relatively large length in the X direction and a length in the Y direction (length of one side). The pixel 30f is a horizontally long large-area pixel having a very large length in the X direction. The pixel 30g is a vertically long rectangular pixel. The pixel 30h is a horizontally long pixel with a very large length in the X direction. As shown in the drawing, the liquid crystal element 11 is provided with pixels of various sizes and shapes other than those illustrated. Each pixel can individually control the transmission/non-transmission of light, and by appropriately controlling these, it is possible to form irradiation light with various light distribution patterns according to the situation ahead of the vehicle. .

In the liquid crystal element 11 shown in FIG. 9, the effective display area is divided into four areas 200A, 200B, 200C and 200D. Boundaries of these areas 200A, 200B, 200C and 200D are indicated by dotted lines in the figure. The area 200A is a quadrangular area substantially in the center in the X direction and relatively upper in the Y direction in the effective display area in plan view. The region 200B is a concave-shaped region in contact with the left and right sides and the lower side of the region 200A in plan view. The region 200C is a recessed region in contact with the left and right sides and the lower side of the region 200B in plan view. The region 200D is a recessed region in contact with the left and right sides and the lower side of the region 200C in plan view. In this embodiment, one or both of the areas 200A and 200B correspond to the "first effective display area", and the area 200C corresponds to the "second effective display area".

Each pixel such as pixels 30c and 30d arranged in the region 200A is a pixel mainly used for forming a light distribution pattern at a position higher than the oncoming vehicle or preceding vehicle in the high beam irradiation range. In this region 200A, although the frequency of switching between light transmission/non-transmission in each pixel such as the pixels 30c and 30d is relatively high, the region 200A is responsible for the light distribution pattern of a portion that does not give glare to oncoming vehicles. Therefore, it can be said that the demand for high light-shielding properties is somewhat low. Therefore, it is preferable to associate the region A shown in FIG. 6 described above, that is, the region within 50% of the relative distance from the injection port 16 (less than the pretilt angle of 84.5°) with this region 200A.

Each pixel such as the pixels 30a and 30b arranged in the region 200B is a pixel used for forming a light distribution pattern mainly at the position where the oncoming vehicle or preceding vehicle exists in the high beam irradiation range. In this area 200B, the light transmission/non-transmission switching frequency in each pixel such as the pixels 30a and 30b is relatively high, and light distribution in a portion where light shielding properties for suppressing glare to oncoming vehicles and the like are required. It bears the pattern. Therefore, the region B shown in FIG. 6 described above, that is, the region where the relative distance from the injection port 16 is 50% or more and less than 80% (the pretilt angle is 84.5° or more and less than 85.5°) is associated with this region 200B. is preferred.

Each pixel such as the pixels 30e and 30f arranged in the region 200C is a pixel mainly used for forming a light distribution pattern in the irradiation range of the low beam and the irradiation range to the road shoulder. This region 200C has a low frequency of switching between light transmission and non-transmission in each pixel such as the pixels 30e and 30f, and is responsible for the light distribution pattern of the portion where high light shielding properties (when turned off) and transmittance (when turned on) are required. It is. Therefore, it is preferable to associate the region C shown in FIG. 6 described above, that is, the region where the relative distance from the injection port 16 is 80% or more and less than 96% (the pretilt angle is 85.5° or more and less than 89°) with this region 200C. .

Each pixel such as the pixels 30g and 30h arranged in the region 200D is a pixel used for forming a light distribution pattern in the irradiation range around the regions 200A to 200C. This region 200D is a region close to the sealing material 15, and there are cases where the pixels 30g and the like are not provided. In this region 200D, the light shielding property should be high, but high responsiveness in switching between light transmission/non-transmission is not required. Therefore, it is preferable to associate the region D shown in FIG. 6 described above, that is, the region where the relative distance from the injection port 16 is 96% or more (the pretilt angle is 89° or more), with this region 200D.

10 is a diagram for explaining the relative distance from the injection port in the liquid crystal element shown in FIG. 9. FIG. In FIG. 10, in the internal region of the sealing material 15, a straight line connects from the position p of the injection port 16 to each part (each position) of the sealing material 15, and the relative distance on the straight line is indicated by percentage. there is For example, on a straight line extending directly downward in the figure from the position p to the sealing material 15, the positions at which the relative distance is 50%, 80%, and 96% are shown, respectively. The same applies to straight lines extending from the position p in other directions to reach the sealing material 15 .

Then, by connecting the positions where the relative distance is 50% on each straight line, a rectangular area showing the range where the relative distance is less than 50% is obtained. The area 200A described above is associated with this area. Similarly, connecting the positions where the relative distance is 80% on each straight line yields a U-shaped area showing the range of the relative distance of 50% or more and 80% or less. The area 200B described above is associated with this area. Similarly, connecting the positions where the relative distance is 96% on each straight line yields a U-shaped area showing the range of the relative distance of 80% or more and less than 96%. The area 200C described above is associated with this area. Similarly, connecting the positions where the relative distance is 100% on each straight line, that is, the position of the sealing member 15, a U-shaped region showing the range where the relative distance is 96% or more is obtained. The area 200D described above is associated with this area. In other words, the position of the injection port 16 is set so as to obtain a preferable pretilt angle distribution for each of the regions 200A to 200D.

FIG. 11 is a schematic cross-sectional view showing a configuration example of a liquid crystal element. Also, FIG. 12 is a schematic plan view showing the configuration of the liquid crystal element. Note that the cross-sectional view shown in FIG. 11 corresponds to a partial cross-section taken along line AA shown in FIG. The liquid crystal element 11 includes a first substrate 311 and a second substrate 312 arranged to face each other, a common electrode (counter electrode) 313, a plurality of pixel electrodes 314, a plurality of inter-pixel electrodes 315, a plurality of wiring portions 316, and a first insulating layer. (insulating film) 317 , a second insulating layer (insulating film) 318 , alignment films 319 and 320 , and a liquid crystal layer 321 . The liquid crystal element 11 can be basically manufactured by the same manufacturing method as the liquid crystal elements 500A and 500B according to the above experiments.

The first substrate 311 and the second substrate 312 are, for example, rectangular substrates in plan view, and are arranged to face each other. As each substrate, for example, a transparent substrate such as a glass substrate or a plastic substrate can be used. Between the first substrate 311 and the second substrate 312, spherical spacers (not shown) made of, for example, a resin film are dispersedly arranged, and these spherical spacers provide a substrate gap of a desired size (for example, several μm). is kept in Instead of spherical spacers, columnar bodies made of resin or the like may be provided on the first substrate 311 side or the second substrate 312 side and used as spacers.

The common electrode 313 is provided on one side of the first substrate 311 . The common electrode 313 is integrally provided so as to face each pixel electrode 314 of the second substrate 312 . The common electrode 313 is formed by appropriately patterning a transparent conductive film such as indium tin oxide (ITO).

A plurality of pixel electrodes 314 are provided on one surface side of the second substrate 312 above the first insulating layer 317 (the side facing the first substrate 311). These pixel electrodes 314 are formed by appropriately patterning a transparent conductive film such as indium tin oxide (ITO). As shown in FIG. 12, each pixel electrode 314 (314a, 314b, 314c) has, for example, a rectangular outer edge shape in plan view, and is arranged in a matrix along the X and Y directions. . A gap is provided between each pixel electrode 314 . The overlapping regions of the common electrode 313 and the pixel electrodes 314 constitute respective pixels such as the pixels 30a to 30h. Note that the symbol Q in the drawing indicates one of the boundaries between adjacent pixel electrodes 314 . The distribution of pretilt angles is determined according to the relative distance from the injection port 15 regardless of the boundary Q, that is, regardless of the position of each pixel electrode 314 .

A plurality of inter-pixel electrodes 315 are provided on the lower layer side of the first insulating layer 317 on the one surface side of the second substrate 312 . These inter-pixel electrodes 315 are formed by appropriately patterning a transparent conductive film such as indium tin oxide (ITO). As shown in FIG. 12, each inter-pixel electrode 315 has, for example, a rectangular outer edge shape in plan view, and overlaps the gap between two adjacent pixel electrodes 314 in the X direction in the drawing. are arranged as Furthermore, in the present embodiment, each inter-pixel electrode 315 partially overlaps the adjacent pixel electrode 314 on the right side in the figure.

A plurality of wiring portions 316 are provided on the lower layer side of the first insulating layer 317 on the one surface side of the second substrate 312 . These wiring portions 316 are formed by appropriately patterning a transparent conductive film such as indium tin oxide (ITO). Each wiring portion 316 is for applying a voltage to each pixel electrode 314 from the driver 12 (see FIG. 7).

The first insulating layer 317 is provided on the one surface side of the second substrate 312 so as to cover the inter-pixel electrodes 315 and the wiring portions 316 . That is, the first insulating layer 317 is provided so as to cover the entire surface of the second substrate 312 except for through holes 329 which will be described later. The first insulating layer 317 is, for example, a SiO ₂ film or a SiON film, and can be formed by a vapor phase process such as sputtering or a solution process. An organic insulating film may be used as the first insulating layer 317 . The layer thickness of the first insulating layer 317 is, for example, about 1 μm.

A second insulating layer 318 is provided on one surface side of the second substrate 312 so as to cover the pixel electrodes 314 . In this embodiment, the second insulating layer 318 is formed so as to have substantially the same shape as the pixel electrodes 314 and selectively cover the pixel electrodes 314 but not cover the gaps between the pixel electrodes 314 . The second insulating layer 318 is formed by filling the through hole 329 so as to cover the connecting portion 330 which is a part of each pixel electrode 314 . This second insulating layer 318 is, for example, a SiO ₂ film or a SiON film, and can be formed by a vapor phase process such as sputtering or a solution process. An organic insulating film may be used as the second insulating layer 318 . The layer thickness of the second insulating layer 318 is, for example, about 1 μm.

The alignment film 319 is provided on one surface side of the first substrate 311 so as to cover the common electrode 313 . Similarly, the alignment film 320 is provided so as to cover the second insulating layer 318 on one surface side of the second substrate 312 and to cover the portion of the first insulating layer 317 exposed between the pixel electrodes 314 . . As each of the alignment films 319 and 320, for example, a vertical alignment film that regulates the alignment state of the liquid crystal layer 321 to vertical alignment is used. Each of the alignment films 319 and 320 is subjected to uniaxial alignment treatment such as rubbing treatment, and has a uniaxial alignment regulating force that regulates the alignment of the liquid crystal molecules of the liquid crystal layer 321 in that direction. The directions of the alignment treatment on the alignment films 319 and 320 are set to be alternate (anti-parallel), for example. The film thickness of each of the alignment films 319 and 320 is, for example, 50 to 70 nm, which is smaller than the layer thickness of the second insulating layer 318 by one order of magnitude or more. Therefore, the alignment film 320 is formed along the undulations caused by the second insulating layer 318 as shown.

A liquid crystal layer 321 is provided between the first substrate 311 and the second substrate 312 . In this embodiment, the liquid crystal layer 321 is formed using a nematic liquid crystal material that has a negative dielectric anisotropy Δε, contains a chiral material, and has fluidity. Also, the liquid crystal layer 321 is polymerized as described above. In the liquid crystal layer 321 of this embodiment, the alignment direction of the liquid crystal molecules is tilted in one direction when no voltage is applied, and has a pretilt angle of, for example, 85° or more and less than 90° with respect to each substrate surface. It is set so as to be substantially vertically oriented. As described above, the pretilt angles are distributed so as to differ in magnitude according to the relative distance from the injection port 16 position.

The structure of each pixel electrode 314, each inter-pixel electrode 315, and each wiring portion 316 will be described in detail with reference to FIG. Here, regarding the pixel electrodes 314, the pixel electrode 314a is in the first column, the pixel electrode 314b is in the second column, and the pixel electrode 314c is in the third column. As for the inter-pixel electrodes 315, the inter-pixel electrodes 315a correspond to the pixel electrodes 314a on the first column, the inter-pixel electrodes 315b correspond to the pixel electrodes 314b on the second column, and the inter-pixel electrodes 315b correspond to the pixel electrodes 314b on the third column. is called an inter-pixel electrode 315c. Further, with respect to the wiring portion 316, those associated with the pixel electrodes 314a and the inter-pixel electrodes 315a in the first column are replaced with the wiring portions 316a, and those associated with the pixel electrodes 314b and the inter-pixel electrodes 315b in the second column are replaced. A wiring portion 316c corresponds to the wiring portion 316b, the pixel electrode 314c in the third column, and the inter-pixel electrode 315c.

Each pixel electrode 314a is connected to the lower inter-pixel electrode 315a and the wiring portion 316a through a through hole 329 provided in the first insulating layer 317 . As a result, the pixel electrode 314a, the inter-pixel electrode 315a, and the wiring portion 316a are brought to the same potential. Each pixel electrode 314a has a connection portion 330a formed along the wall surface of the through hole 329. As shown in FIG. The connecting portion 330a is in contact with the lower inter-pixel electrode 315a and the portion of the wiring portion 316a exposed at the bottom of the through hole 329. As shown in FIG.

Similarly, each pixel electrode 314b has a connecting portion 330b formed along the wall surface of the through-hole 329, and is connected to the lower inter-pixel electrode 315b and wiring portion 316b. As a result, the pixel electrode 314b, the inter-pixel electrode 315b, and the wiring portion 316b are brought to the same potential. Similarly, each pixel electrode 314c has a connection portion 330c formed along the wall surface of the through-hole 329, and is connected to the lower inter-pixel electrode 315c and wiring portion 316c. As a result, the pixel electrode 314c, the inter-pixel electrode 315c, and the wiring portion 316c are brought to the same potential.

Each inter-pixel electrode 315a is arranged so as to overlap a gap between two pixel electrodes 314a adjacent to each other in the X direction in plan view. In each inter-pixel electrode 315a, a partial area 415a inside from its right edge in plan view partially overlaps a partial area near the left outer edge of the pixel electrode 314a arranged on its right. are arranged as These partial regions 415a have the effect of preventing oblique electric fields from being generated in the vicinity of the left outer edge of the pixel electrode 314a in the drawing, thereby suppressing the generation of dark regions. For this reason, it is preferable that the Y-direction length of each partial region 415a is as wide as possible. ing.

Similarly, each inter-pixel electrode 315b is arranged so as to overlap a gap between two pixel electrodes 314b adjacent to each other in the X direction in a plan view, and a partial region 415b is formed so as to overlap the pixel electrode 314b on the right side of itself. are arranged so as to partially overlap with the Similarly, each inter-pixel electrode 315c is arranged so as to overlap the gap between two pixel electrodes 314c adjacent to each other in the X direction in a plan view, and the partial region 415c is the pixel electrode 314c on the right side of itself. are arranged so as to partially overlap with the

Each wiring portion 316a is connected to one of the inter-pixel electrodes 315a and extends upward in the figure. In this embodiment, each wiring portion 316a is integrally provided with the same width as the corresponding inter-pixel electrode 315a.

Each wiring portion 316b is connected to one of the inter-pixel electrodes 315b and extends upward in the figure. Each wiring portion 316b has, in plan view, a partial region 416b that partially overlaps the pixel electrode 314b that is adjacent in the X direction with respect to the inter-pixel electrode 315b that is connected to the wiring portion 316b. It has a partial region 426b arranged between adjacent pixel electrodes 314a and a partial region 436b arranged overlapping with the pixel electrodes 314a. Each partial region 416b, 426b, 436b is integrally provided.

Each partial region 416b of each wiring portion 316b has the effect of suppressing the occurrence of a dark region near the upper outer edge of the pixel electrode 314b in the drawing, similarly to the partial region 415b described above. For this reason, it is preferable that the width of each partial region 416b in the X direction is as large as possible. In the illustrated example, the width of each partial region 416b is about 70% of the width of the associated pixel electrodes 314a and 314b.

Each partial region 426b of each wiring portion 316b also functions as an inter-pixel electrode arranged between two pixel electrodes 314a and 314b adjacent to each other in the Y direction. For this reason, the X-direction length of each partial region 426b is preferably as large as possible. In the illustrated example, the width of each partial region 426b is approximately 70% of the X-direction length of the associated pixel electrodes 314a and 314b. By providing such a partial region 426b, a region that substantially functions as a pixel region can be expanded.

Each wiring portion 316c is connected to one of the inter-pixel electrodes 315c and extends upward in the figure. Each wiring portion 316c has, in plan view, a partial region 416c that partially overlaps the pixel electrode 314c that is adjacent in the X direction with respect to the inter-pixel electrode 315c connected thereto, and a partial region 416c that is adjacent to the pixel electrode 314c in the Y direction. A partial region 426c arranged between the matching pixel electrodes 314b, a partial region 436c arranged to overlap with the pixel electrodes 314b with the first insulating layer 317 interposed therebetween, and adjacent to the pixel electrodes 314b in the Y direction. A partial region 446c is arranged to overlap with the matching pixel electrode 314a with the first insulating layer 317 interposed therebetween, and a partial region 436c and a partial region 446c are arranged between the pixel electrode 314a and the pixel electrode 314b to connect the partial region 436c and the partial region 446c. It has a connection region 456c that connects. The partial regions 416c, 426c, 436c, 446c and the connection region 456c are provided integrally.

Each partial region 416c of each wiring portion 316c has the effect of suppressing the occurrence of a dark region near the upper outer edge of the pixel electrode 314c in the drawing, similarly to the partial region 415c described above. Therefore, the X-direction length of each partial region 316c is preferably as wide as possible, and preferably has a length of 50% or more of the X-direction length of the corresponding pixel electrodes 314b and 314c. In the illustrated example, the length of each partial region 416c is about 87% of the length in the X direction of the associated pixel electrodes 314b and 314c.

Each partial region 426c of each wiring portion 316c also functions as an inter-pixel electrode arranged between two pixel electrodes 314b and 314c adjacent to each other in the Y direction. Therefore, the X-direction length of each partial region 426c is preferably as large as possible. In the illustrated example, the length of each partial region 426c is about 87% of the X-direction length of the associated pixel electrodes 314b and 314c. By providing such a partial region 426c, a region that substantially functions as a pixel region can be expanded.

In this way, since the inter-pixel electrode or part of the wiring portion functioning equivalently to the inter-pixel electrode is provided between the pixel electrodes, the monomer contained in the liquid crystal material during the manufacture of the liquid crystal element 11 is polymerized by irradiating ultraviolet rays. A voltage can be applied across the entire liquid crystal layer when the liquid crystal layer is formed. As a result, local disturbances in the pretilt angle distribution are less likely to occur.

Here, when a voltage is applied to the pixel electrode 314c to put the region into a light-transmitting state, the same voltage is applied to the connection region 456c, so that the connection region 456c also becomes a light-transmitting state. At this time, for example, if each region corresponding to the pixel electrode 314a or the pixel electrode 314b is in a non-transmissive state (or a low-transmissive state), the light-transmissive state of the connection region 456c can be visually recognized as a bright spot. Therefore, by providing a portion of the second insulating layer 318 so as to overlap each connection region 456c of each wiring portion 316c, it is possible to suppress the generation of bright spots in the portion corresponding to each connection region 456c. This is because the overlapping of the first insulating layer 317 and the second insulating layer 318 can reduce the voltage applied to the liquid crystal layer 321 in this region.

Since the connection region 456c is in a non-transmissive state in many cases, it can be visually recognized as a black dot. However, it can be said that the black dot is less conspicuous due to the characteristics of the human eye, and thus is preferable to a bright spot. Furthermore, as shown in the figure, the connection region 456c is for electrically connecting the partial region 436c and the partial region 446c, so it can be formed in a relatively narrow size. Therefore, it is possible to make the black spots practically invisible.

FIG. 13 is an image diagram showing a specific example of illumination light generated by the vehicle lamp system. As shown in the figure, for example, each pixel in the region 200B of the liquid crystal element 11 described above is used to determine a dimming range (shading range) 600 corresponding to an oncoming vehicle, a dimming range (shading range) 601 corresponding to a preceding vehicle, and a walking distance. It is possible to generate irradiation light having a light distribution pattern including a dimming range 602 corresponding to the person's head. Since the region 200B of the liquid crystal element 11 is used, the dimming range 600 and the like with high responsiveness and high light shielding properties can be obtained. Further, each pixel in the region 200A of the liquid crystal element 11 can be used to generate the dimming range 603 corresponding to the guide plate.

According to the above-described embodiments, it is possible to obtain a liquid crystal element having a pretilt angle distribution independent of the position of the pixel electrode or the like, or a device having the same. A liquid crystal element having a distribution of pretilt angles can be manufactured.

It should be noted that the present disclosure is not limited to the contents of the above-described embodiments, and various modifications can be made within the scope of the gist of the present disclosure. For example, the configuration of the vehicle lamp is not limited to that shown in FIG. Similarly, the configuration of the vehicle lamp system is not limited to that shown in FIG. Further, the plan view structure of the pixel of the liquid crystal element is not limited to that shown in FIG. 9, and the cross-sectional structure of the liquid crystal element is not limited to that shown in FIG. Furthermore, although the vehicle lamp is mentioned as an example of the lighting device, the lighting device is not limited to this.

Further, in the above-described embodiment, the case where the same voltage is applied to the entire liquid crystal layer when the monomer contained in the liquid crystal material is polymerized by irradiating ultraviolet rays was exemplified. Different settings may be made depending on the position. Specifically, as an example is shown in FIG. 14, the pretilt angle can be changed by increasing or decreasing the voltage applied to the liquid crystal layer during polymerization. Specifically, the higher the applied voltage, the smaller the pretilt angle. Therefore, by increasing or decreasing the applied voltage, it is possible to adjust the magnitude of the pretilt angle determined according to the relative distance from the inlet. By individually setting the voltage applied to each pixel electrode, the pretilt angle can be set to a desired value with higher accuracy.

When adjusting the pretilt angle by applying voltage as described above, the pretilt angle can be adjusted more positively by partially irradiating ultraviolet rays using a photomask. . For example, a desired pretilt angle can be obtained by applying a voltage that can obtain a required pretilt angle while considering the polymer concentration in the portion to be irradiated with ultraviolet rays. By repeating such a process for each portion, a desired pretilt angle distribution can be finally obtained for the entire liquid crystal layer. At this time, a halftone mask is used to irradiate ultraviolet rays at the boundary of each portion, or the applied voltage is finely adjusted to suppress the distribution of the pretilt angle from becoming discontinuous at the boundary of each portion. can be done.

1: vehicle lighting system, 10: light source, 11: liquid crystal element, 12: driver, 13a, 13b: polarizing element (polarizing plate), 14: projection lens, 15: sealing material, 16: inlet (opening), 100 : vehicle lamp, 101: light distribution control unit, 102: forward monitoring unit 103: vehicle-mounted camera

Claims (13)

a first substrate and a second substrate arranged so that their one surface sides face each other;
a sealing material arranged substantially annularly between the first substrate and the second substrate;
a liquid crystal layer arranged between the first substrate and the second substrate and surrounded by the sealing material;
including
The sealing material has one opening in plan view,
The pretilt angle in the liquid crystal layer varies in magnitude depending on the distance from the opening in plan view,
liquid crystal element. The pretilt angle increases as the distance from the opening increases.
The liquid crystal device according to claim 1. The distance from the opening is a relative distance normalized based on the straight line distance connecting each part of the opening and the sealing material,
3. The liquid crystal device according to claim 1. a first vertical alignment film disposed on one side of the first substrate;
a second vertical alignment film disposed on one side of the second substrate;
including
Each of the first vertical alignment film and the second vertical alignment film has a uniaxial alignment force developed by a rubbing treatment,
The liquid crystal device according to any one of claims 1 to 3. The liquid crystal layer is polymer-stabilized and has substantially vertical alignment when no voltage is applied.
5. The liquid crystal device according to claim 4. The sealing material is provided in a substantially rectangular shape or a substantially square shape in plan view,
The opening is arranged in correspondence with substantially the center of one of the four sides of the sealing material,
The liquid crystal device according to any one of claims 1 to 5. a first conductive film disposed between the one surface of the first substrate and the first vertical alignment film;
a second conductive film disposed between the one surface of the second substrate and the second vertical alignment film;
including
The first conductive film and/or the second conductive film are provided substantially symmetrically with respect to the axis of symmetry of the sealing material in a plan view.
7. The liquid crystal device according to claim 6. the first conductive film includes a plurality of pixel electrodes;
The pretilt angle varies in magnitude according to the distance from the aperture, regardless of boundaries between the plurality of pixel electrodes.
The liquid crystal device according to claim 7. A liquid crystal device according to any one of claims 1 to 8;
a pair of polarizing elements arranged opposite to each other with the liquid crystal element interposed therebetween;
a light source for causing light to enter the liquid crystal element;
A lighting device, comprising: a vehicle lamp configured using the lighting device according to claim 9;
a controller that applies a drive voltage to the liquid crystal element of the vehicle lamp in accordance with a situation around the vehicle;
a lens for condensing the light transmitted through the liquid crystal element and projecting the light onto the periphery of the vehicle;
A vehicle lighting system, comprising: A method for manufacturing a liquid crystal element,
(a) preparing a first substrate and a second substrate each having a conductive film on one surface side;
(b) forming a vertical alignment film on one side of each of the first substrate and the second substrate;
(c) rubbing the vertical alignment films of the first substrate and the second substrate;
(d) forming a substantially annular sealing material having one opening in plan view on one surface side of the first substrate or the second substrate;
(e) bonding the first substrate and the second substrate so that one surface sides of each are opposed to each other;
(f) injecting a liquid crystal material containing a monomer that polymerizes by light irradiation into a space between the first substrate and the second substrate and surrounded by the sealing material through the opening;
(g) applying light to the liquid crystal material through the first substrate and/or the second substrate while applying a voltage to the liquid crystal material using the conductive films of the first substrate and the second substrate; to polymerize the monomer,
A method for manufacturing a liquid crystal element, comprising: a light source;
a liquid crystal element including a first substrate and a second substrate arranged so that one surface sides thereof face each other; and a liquid crystal layer arranged between the first substrate and the second substrate;
an optical system for causing the light from the light source to enter the liquid crystal element;
with
the liquid crystal element includes a first effective display area and a second effective display area each having at least one pixel;
the pretilt angle in the first effective display area is smaller than the pretilt angle in the second effective display area;
light passing through the first effective display area constitutes a high-beam light distribution pattern,
light passing through the second effective display area constitutes a low-beam light distribution pattern;
Vehicle lighting. wherein the first effective display area comprises a plurality of pixels;
The vehicle lamp according to claim 12.

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