JP7635007B2 - In-vehicle information display device - Google Patents

Description

The present invention relates to an in-vehicle information display device that is installed in vehicles used for the operation and management of expressways and highways, and displays information such as accident occurrences and road maintenance work to passing vehicles.

Conventionally, in the operation and management of expressways and highways, dedicated vehicles used for operation and management are equipped with an on-board information display device that can be seen from behind through the rear window. The vehicle moves to the scene of an accident or a location where road maintenance work is being performed, and displays information such as "Accident ahead, road closed" or "Work in progress" to provide necessary information to passing vehicles.

For example, an LED information display board as shown in Patent Document 1 and a blind-type vehicle-mounted information board as shown in Non-Patent Document 1 are known as such conventional in-vehicle information display devices. These information display boards are LED-row boards in which multiple LEDs are arranged horizontally in a horizontally long rectangular outer frame, for example, 15 rows are arranged vertically with gaps between them to form an LED dot matrix on the display surface, and when placed in front of the rear window inside the vehicle, the LEDs are selectively lit up and down according to character strings set by operating a controller to display the required information.

In addition, the information display board has LED panels arranged vertically with gaps between them on the outer frame, so even if it is placed in front of the rear window inside the vehicle, the driver can see behind the vehicle through the information display board, making it possible to drive safely while checking behind the wheel.

Utility Model Registration No. 3224356 JP 2020-038895 A JP 2019-216246 A

"Blind-type vehicle-mounted information board instruction manual" https://www. i-tex. co. jp/buraindo. html

However, with conventional in-vehicle information display devices, although it is possible to see the rear through the rear window, the information display board is constructed by arranging LED rows vertically with a see-through area (gaps) in the outer frame, so the area of the see-through area relative to the rear field of vision is reduced to, for example, around 70%, making it difficult to see the rear.

Furthermore, conventional in-vehicle information display devices have LEDs arranged in a vertical array on the rear window side of the LED row plate, facing towards the rear of the vehicle. When information is displayed by selectively turning on and off the LEDs, even if the driver tries to check the status of the information display, for example, by using the rearview mirror, it is completely invisible from the opposite side of the display surface on which the information is displayed (the back side of the display), which causes the inconvenience of being unable to check whether the information displayed on the controller display is actually being displayed.

The main objective of the present invention is to provide an in-vehicle information display device that makes it easier to see the view outside the vehicle cabin from inside the cabin through the in-vehicle information display device, and additionally makes it easy to check the actual display status of information for the outside of the vehicle.

(In-vehicle information display device 1)
The present invention provides an in-vehicle information display device that displays predetermined information on a display surface so as to be visible from outside the vehicle,
a plurality of light-emitting sections disposed on a light-transmitting display substrate and configured to emit light in two directions, that is, toward the display surface and toward an opposite surface of the display substrate;
a plurality of light-shielding sections that are arranged on a display back side that is an opposite surface side corresponding to the positions of the plurality of light-emitting sections and that block light emitted from the light-emitting sections at the respective positions to the display back side ;
Equipped with
the plurality of light-emitting sections form back-side light-emitting points at which light leaks from the plurality of light-shielding sections to the display back side when the light-emitting sections emit light, and the periphery of the plurality of light-shielding sections is visually recognized as being brighter than the light-shielding sections when viewed from the display back side;
The plurality of light-shielding portions are characterized by being arranged so that information displayed on the display surface can be viewed from the rear surface side of the display due to the arrangement of the rear surface light-emitting points.

(In-vehicle information display device 2)
The present invention provides an in-vehicle information display device that displays predetermined information on a display surface so as to be visible from outside the vehicle,
a plurality of light-emitting sections disposed on a light-transmitting display substrate and configured to emit light in two directions, that is, toward the display surface and toward an opposite surface of the display substrate;
a display unit in which a plurality of light-emitting units are arranged in a matrix at a predetermined interval such that information can be viewed when the display unit is moved away from the display unit by a predetermined distance or more, and which displays information on a display surface by selectively driving the light-emitting units to emit light;
a plurality of light-shielding sections that are arranged on a display back surface side that is an opposite surface side corresponding to the positions of the plurality of light-emitting sections and that block light emitted from the plurality of light-emitting sections at the positions where the light -emitting sections are arranged to the display back surface side;
Equipped with
the display unit forms back-side light-emitting points at which the periphery of the plurality of light-shielding parts appears brighter than the light-shielding parts when viewed from the back side of the display unit due to leakage light from the plurality of light-shielding parts to the back side of the display unit when the plurality of light-emitting parts are driven to emit light;
The plurality of light-shielding portions are characterized by being arranged so that information displayed on the display surface can be viewed from the rear surface side of the display due to the arrangement of the rear surface light-emitting points.

In the following description, the side opposite the "display surface (side)" of the in-vehicle information display device is defined as the "display back surface (side)" in the same manner as in the description of the in-vehicle information display devices 1 and 2 described above.

(Arrangement of display part with inverted display and reflective visibility)
The information based on the arrangement of rear light emitting points, which is left and right inverted when viewed from the rear surface of the display, is reflected by a rearview mirror and further inverted left and right, and is installed at a position where it can be viewed in the same way as when viewed from the display surface side.

(Installed on rear window)
It is installed in a position that is visible from the rear of the vehicle through the rear window of the passenger compartment.

(Reflective structure of light-shielding part)
The light blocking portion has a reflecting surface facing the light emitting portion.

(Adjustment of the light blocking degree of the light blocking part)
The degree to which the light-shielding portion blocks light traveling from the light-emitting portion to the rear display surface is adjusted to a predetermined degree by adjusting the color density or by forming a slit of a predetermined shape that does not block light .

(Arrangement of light-shielding substrate body)
A light-shielding substrate having translucency and in which light-shielding portions are arranged corresponding to the positions of the light-emitting portions is provided on the rear display surface side of the display substrate.

(Light shielding part of liquid crystal structure)
The light-shielding portion disposed on the light-shielding substrate has a liquid crystal structure in which the light transmittance is maximum when no voltage is applied, and the light transmittance changes in response to the applied voltage when a voltage is applied.

(Color display of information)
The light emitting section has light emitting sites that emit the three primary colors of light, and each light emitting section independently emits light of a predetermined color.

(Flexible display substrate and light-shielding substrate)
The display substrate, or, if a light-shielding substrate is provided, the display substrate and the light-shielding substrate have flexibility.

(Effects of in-vehicle information display devices)
According to the in-vehicle information display device of the present invention, even if a plurality of light-emitting elements are provided on a translucent display substrate, the light directed from the light-emitting elements to the back surface of the display is blocked by the light-shielding portion covering the back surface of the display at the position of each light-emitting element, so that it is possible to safely and easily check the outside of the vehicle cabin from inside the vehicle (back surface of the display) through the in-vehicle information display device in the information display state without being directly exposed to light from the light-emitting elements.

In addition, the field of view when viewed from the back side of the display is merely obstructed by, for example, dot-shaped light-shielding sections arranged on the back side of the display substrate with translucency in correspondence with the positions of the light-emitting sections arranged, for example, in a matrix. Therefore, the area occupied by the light-shielding sections is small, for example, less than about 10% of the total area. By increasing the area occupied by the light-transmitting areas (gaps) to, for example, 90% or more, it becomes easier to check the outside of the vehicle through the in-vehicle information display device, enabling safe driving operations while information is displayed.

(Effect of the light-shielding part that enables information to be viewed from the back side of the display)
In addition, when information is displayed on the display unit by driving the light-emitting units to emit light, the light-shielding units are arranged in correspondence with the position of each light-emitting unit, so that the light from the light-emitting units is not directly irradiated onto the back surface of the display. However, from within the vehicle cabin, the light-shielding units appear to stand out in a dark color due to light leaking from around them, and the driver can view the information currently displayed on the display surface in a left-right inverted state due to the leaking light and the light-shielding units. This allows the driver to check the information currently displayed without checking the displayed content on the controller or going outside the vehicle cabin.

(Effect of placement on rear window)
In addition, when the vehicle-mounted information display device is used to look behind using a mirror such as a rearview mirror, the information that is already inverted left to right is further inverted, allowing the information to be viewed in the same state as when it is displayed toward the outside of the vehicle, making the displayed information easily visible.

(Effect of the reflective structure of the light-shielding part)
In addition, the light-shielding portion reflects light from the light-emitting portion toward the back display side toward the display surface side by using a light-shielding surface facing the light-emitting portion as a reflective surface, thereby improving the degree of light irradiation on the display surface side and making it possible to increase the brightness of the light-emitting portion. In particular, the light-emitting portion provided on the display substrate having translucency has an orientation characteristic of emitting light to both the front and back sides, but the light from the light-emitting portion toward the back display side is reflected by the reflective surface of the light-shielding portion, improving the light distribution characteristic to the front, making it possible to increase the brightness of the light-emitting portion as viewed from the front.

(Effect of adjusting the degree of light blocking of the light blocking part)
In addition, the light-shielding portion is capable of adjusting the degree to which it blocks light from the light-emitting portion toward the back surface of the display to a predetermined degree, thereby adjusting the brightness to an appropriate level that is not dazzling when viewed from within the vehicle cabin, and at the same time, information is displayed on the back surface of the display using light that has passed through the light-shielding portion itself, making it easy to check the currently displayed information from within the vehicle cabin.

(Effect of light-shielding substrate)
Furthermore, by providing a light-transmitting light-shielding substrate body on the display back surface side of the display substrate body, in which light-shielding portions are arranged corresponding to the positions of the light-emitting portions, a structure in which the light-shielding portions are arranged on the display back surface side of the light-emitting portions can be easily produced by stacking or overlapping the display substrate body on which the light-emitting portions are arranged and the light-shielding substrate body on which the light-shielding portions are arranged. Furthermore, by preparing, for example, a display substrate body having a plurality of types of light-emitting portions with different light emission and a light-shielding substrate body having a plurality of types of light-shielding portions with different light-shielding degrees, production corresponding to various in-vehicle information display devices can be made.

(Effect of the light-shielding part of the liquid crystal structure)
Furthermore, by making the light-shielding sections arranged on the light-shielding substrate have a liquid crystal structure in which the light transmittance is maximum when no voltage is applied and the light transmittance changes according to the applied voltage when voltage is applied, when no information is being displayed, no voltage is applied to the liquid crystal structure, thereby maximizing the light transmittance to the rear, and rear visibility is not obstructed even if the display unit is located in front of the rear window of the vehicle interior.

In addition, when information is being displayed, the light transmittance of the liquid crystal structure functioning as a light-shielding section can be changed to any desired value by adjusting the voltage applied to the liquid crystal structure, making it possible to freely adjust the degree of light-shielding of the light-shielding section, for example, to an appropriate brightness that is not too dazzling when the driver looks into the rearview mirror.

(Effect of color display of information)
In addition, the light-emitting unit has light-emitting parts that emit the three primary colors of light, and each light-emitting unit independently emits light in a predetermined color, making it possible to effectively display information in various forms, including color display.

(Effect of flexible display substrate and light-shielding substrate)
Furthermore, the display substrate and the light-shielding substrate have flexibility, and therefore can be arranged, for example, curved, in accordance with the structure of the installation location, without depending on the structure of the installation location.

1 is an explanatory diagram showing a vehicle equipped with an in-vehicle information display device according to the present invention; 1 is an explanatory diagram showing an embodiment of an in-vehicle information display device; FIG. 2 is an explanatory diagram showing the rear display side of the display unit. FIG. 2 is an explanatory diagram showing a cross-sectional structure of a display unit. FIG. 2 is an explanatory diagram showing a display state of information by the in-vehicle information display device. 6 is an explanatory diagram showing the display information of FIG. 5 as viewed from the back side of the display. FIG. FIG. 2 is an explanatory diagram showing the display substrate body taken out. 3A to 3C are explanatory diagrams showing a part of a display substrate body in an enlarged manner, the display surface side, a cross section, and the display back surface side. 11 is an explanatory diagram showing an embodiment of a light-shielding portion disposed on the rear display side of a display substrate body. FIG. 11 is an explanatory diagram showing an embodiment of a display substrate in which a light-shielding portion having a reflective surface is arranged. FIG. 11 is an explanatory diagram showing an embodiment of a display unit in which a light-shielding substrate having a liquid crystal structure is disposed on the rear display surface side of a display substrate. FIG.

Below, an embodiment of the in-vehicle information display device according to the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the following embodiment.

[Basic Concept of the Embodiment]
First, a basic concept of the embodiment will be described. The embodiment generally relates to an in-vehicle information display device that displays predetermined information in a manner that is visible from outside the vehicle.

The in-vehicle information display device displays predetermined information on a display surface that is visible from outside the vehicle, and is composed of a display section and a light-shielding section.

The "display unit" refers to a display substrate having translucency, on which multiple light-emitting elements are arranged, for example in a matrix, at a predetermined interval that allows information to be viewed when the display substrate is placed at a distance greater than a predetermined distance, and information is displayed on the display surface by selectively driving the multiple light-emitting elements to emit light.

Here, a "translucent display substrate" refers to a transparent display substrate that transmits light to the display surface side and the display back side, and is a concept that includes transparent films, transparent sheets, transparent panels, etc. The display substrate is also a concept that includes flexible transparent films, transparent sheets, or transparent panels that are flexible and can be bent, as well as those that do not have flexibility.

In addition, "plurality of light-emitting units are arranged in a matrix at a predetermined interval such that information can be viewed from a distance greater than a predetermined distance" is a concept that includes the pixel pitch (pixel spacing) of a large screen that allows images to be viewed from a distance outdoors, etc. In this case, the pixel pitch is generally determined by the minimum appropriate visible distance. For example, the relationship between pixel pitch and minimum appropriate visible distance has been empirically established as follows:
Pixel pitch (mm) x 1.16 x 1000 = minimum proper viewing distance (m)
The "minimum appropriate visibility distance" in this embodiment is a predetermined distance between vehicles at which the information on the display surface mounted on the vehicle can be properly viewed from behind when the display is installed on the rear window of the vehicle interior, and if this distance is, for example, 30 m and applied to this equation, the interval between the light-emitting elements (pixel pitch) is approximately 26 mm.

The term "light-emitting unit" refers to a light-emitting element that is electrically driven to emit light, and is a concept that includes light-emitting diodes (LEDs), organic light-emitting diodes (ELs), display pixels, etc.

In addition, the light-emitting unit has light-emitting parts that emit the three primary colors of light, and each light-emitting unit independently emits light in a predetermined color, making it possible to display information in any color.

The "light blocking section" that constitutes the in-vehicle information display device blocks light and is arranged on the back side of the display from the light emitting section in accordance with the position of each light emitting section, blocking light traveling from the light emitting section at the arranged position toward the back side of the display.

The function of the light blocking section is to block light from the light emitting section toward the back side of the display when viewed from the back side of the display, for example when the display is installed on the rear window inside the vehicle and the driver looks backward, thereby reducing glare, and to minimize the obstruction of the field of view when looking backward through the vehicle through the in-vehicle information display device. Here, "minimizing the obstruction of the field of view" means to secure the minimum necessary area of the light blocking section to block light from the light emitting section toward the back side of the display, and to maximize the area that allows the outside of the vehicle to be seen through the in-vehicle information display device, and includes, for example, a concept that allows the area occupied by the light transmitting area (gap) to be 90% or more, which is superior to conventional methods, i.e., the area occupied by the light blocking section to be 10% or less, thereby enabling the appropriate visibility of the outside of the vehicle as viewed through the in-vehicle information display device from the back side of the display (inside the vehicle interior).

The light-shielding portion allows information to be viewed from the back side of the display due to light leaking from the light-shielding portion when the light-emitting portion is driven to emit light, and the information viewed from the back side of the display is inverted left and right. However, when the information is installed on the rear window of a vehicle and viewed from the driver's seat via the rearview mirror, the information is further inverted left and right, so the information can be properly viewed in the same state as the information displayed on the display surface.

In addition, the light-shielding portion has a reflective surface facing the light-emitting portion, which makes it possible to efficiently utilize the light emitted from the light-emitting portion and increase the display brightness when viewed from the front.

In addition, the light-shielding section allows the degree to which it blocks light traveling from the light-emitting section to the back side of the display to be adjusted to a predetermined degree.

Here, "degree of light blocking" refers to the light blocking rate of the light blocking portion itself; if the light blocking rate is 100%, the light is completely blocked, and if it is 0%, the light is completely transmitted, blocking the light according to the value of the light blocking rate. The light blocking rate also has an inverse relationship to the light transmittance, which indicates the degree of light transmission. Therefore, it can also be said that "the light blocking portion adjusts the degree to which the light traveling from the light emitting portion to the back display surface is transmitted (light transmittance) to a predetermined degree."

The light-shielding sections can also be provided on a light-shielding substrate having light-transmitting properties and arranged in correspondence with the positions of the light-emitting sections on the display back side of the display substrate. In this case, for example, each light-shielding section of the light-shielding substrate can have a liquid crystal structure, and the light transmittance can be maximized when no voltage is applied, and can be adjusted by changing the light transmittance according to the applied voltage when a voltage is applied. The light-shielding substrate can also be flexible like the display substrate.

Specific embodiments are described below. In the specific embodiments described below, the in-vehicle information display device is installed in a position that is visible from the rear of the vehicle through the rear window of the vehicle interior, the light-shielding portion is provided on the display back side of the display substrate, and the display substrate is flexible.

[Specific embodiments of the in-vehicle information display device]
The specific contents of the embodiment of the in-vehicle information display device will be described in more detail below. The contents will be described separately as follows.
a. Mounted vehicle b. In-vehicle information display device c. Display unit d. Display control unit and controller e. Display substrate f. Light-shielding unit f1. Shape of the light-shielding unit f2. Adjustment of the degree of light-shielding f3. Reflective surface of the light-shielding unit f4. Light-shielding unit of liquid crystal structure g. Modification of the present invention

[a. On-board vehicle]
First, a vehicle equipped with the on-board information display device of this embodiment will be described in detail. As shown in Fig. 1(A), a dedicated vehicle 12 used for the maintenance and management of expressways, motorways, etc. is provided with an on-board information display device 10 of this embodiment installed so that information displayed on the display surface can be viewed from the outside. The installation location is arbitrary as long as it is visible from outside the vehicle, but for example, as shown in Fig. 1(B), it is installed at a position visible from the rear of the vehicle 12 through a rear window 14 of the passenger compartment.

The specific information displayed by the in-vehicle information display device 10 is, for example, specific information necessary for the operation and management of roads. Specifically, when inspection work such as checking the road condition while driving at a low speed is being performed, the message "Inspection in progress" is displayed as shown in FIG. 1(B), when a traffic accident occurs, the display moves to the location of the accident and repeatedly displays, for example, "Up ahead," "Accident," and "Road closed," switching between the two in turn, and when road maintenance work is being performed, the display moves to the work location and displays information such as "Work in progress."

The in-vehicle information display device 10 of this embodiment has a transparent display unit that is translucent, so that the rear view seen from the rear window 14 can be confirmed through the in-vehicle information display device 10 from inside the vehicle cabin (the back side of the display), for example, by checking the rearview mirror 16 from the driver's seat. In addition, information such as "Inspection in progress" displayed on the display surface by the display unit can be viewed from inside the vehicle cabin (the back side of the display) in a left-right inverted state, and when viewed through the rearview mirror 16, the information that is inverted left-right when viewed from the back side of the display is reflected again in a left-right inverted state, so that the "Inspection in progress" information displayed on the display surface side of the display unit can be viewed in the correct order.

[b. In-vehicle information display device]
An embodiment of the in-vehicle information display device will be described in more detail. In the drawings explaining the following embodiments, the position is specified by an orthogonal coordinate system of X, Y, and Z directions, where the X direction includes the concept of left-right direction (horizontal direction), the Y direction includes the concept of up-down direction (vertical direction), and the Z direction includes the concept of front-rear direction (front-rear direction). In addition, the front side is the display surface side, and the back side is the display back side.

As shown in FIG. 2, the in-vehicle information display device 10 of this embodiment includes a display unit 18, a display control unit 28, and a controller 30.

[c. Display unit]
The display unit 18 will be described in more detail. As an example, as shown in FIG. 2, the display unit 18 has a horizontally long display substrate 20 disposed in a horizontally long display frame 22. The display substrate 20 is a transparent and flexible thin film substrate having translucency and flexibility, and a plurality of light-emitting units 24 are disposed in a matrix on the display substrate 20. The light-emitting units 24 also have translucency and are transparent when not driven to emit light. The light-emitting units 24 include light-emitting elements that are electrically driven to emit light, and the light-emitting elements are arbitrary, but light-emitting diodes (LEDs) are used, for example. The display substrate 20 is a thin film, and has a thickness of 1 mm or less, for example, about 0.6 mm. The light transmittance of the display substrate 20 is generally 80% or more.

The multiple light-emitting sections 24 arranged in a matrix on the display substrate 20 are rectangular element shapes, as shown enlarged in the lower left corner of Figure 2 as an example, and are arranged at pixel pitch Px in the X direction and pixel pitch Py in the Y direction, and by setting Px = Py, they are arranged at the same pixel pitch in the X and Y directions.

The pixel pitches Px and Py of the light-emitting units 24 are set to pixel pitches that allow the information displayed by the selective light-emission drive of the light-emitting units 24 arranged in a matrix to be properly visible when the display surface of the in-vehicle information display device 10 is viewed from a position that is more than a predetermined distance away. The pixel pitches Px and Py of the light-emitting units 24 can be determined in any manner, but when they are determined based on the aforementioned relational equation between pixel pitch and minimum appropriate visibility distance, the vehicle distance that is the minimum appropriate visibility distance is arbitrary, but when the vehicle distance is set to 30 m, for example, the pixel pitches Px and Py are approximately 26 mm. The following embodiment takes as an example a case where the pixel pitches Px and Py are set to 26 mm by setting the vehicle distance to 30 m.

The matrix arrangement of the light-emitting units 24 on the display substrate 20 can be arbitrary, but for example, 20 units are arranged in the Y direction and 40 units in the X direction in 20 rows and 40 columns, and the number of pixels provided by the light-emitting units 24 is 20 x 40 = 800 pixels.

The size of the display substrate 20 is arbitrary, but for example, it is 26 mm x 41 = 1066 mm in the X direction and 26 mm x 21 = 546 mm in the Y direction, and is sized so that it can be installed inside the cabin of the vehicle 10 and the information displayed on the display surface can be viewed from outside the cabin through the rear window 14, as shown in FIG. 1.

Figure 3 shows the display back side of the display unit 18. On the display back side of the light-emitting display body 20 supported by the display frame 22, light-shielding units 26 are arranged in a matrix at positions covering the display back side corresponding to each of the light-emitting units 24 shown in Figure 2. The light-shielding units 26 block light toward the display back side to a predetermined degree when the light-emitting unit 24 at the arranged position is driven to emit light, and are shaped and sized to cover and conceal the light-emitting units 24 from the display back side.

As an example, the multiple light-shielding sections 26 arranged on the display back side of the display substrate 20 are either circular in shape with a diameter equal to the length of the diagonal of the rectangular shape of the light-emitting section 24, or circular in shape with a diameter larger than that, as shown enlarged in the lower right of Figure 3, and are arranged at pixel pitch Px in the X direction and pixel pitch Py in the Y direction, similar to the light-emitting section 24, and by setting Px = Py, they are arranged at the same pixel pitch in the X direction and the Y direction, and Px = Py = 26 mm.

The light-shielding portion 26 does not transmit light or blocks light to a predetermined degree so that the light transmittance is low, so that the field of view seen through the transparent display substrate 20 from the back side of the display is obstructed by the area of the light-shielding portion 26. However, since the area of the light-shielding portion 26 occupies 10% or less of the entire display substrate 20 so that the area of the light-transmitting area of the display substrate 20 is, for example, 90% or more, there is almost no reduction in the field of view due to the light-shielding portion 26, and the field of view behind the vehicle is sufficiently secured and can be properly viewed from the back side of the display through the in-vehicle information display device 10.

As an example, in the case of a rectangular light-emitting section 24 of 6 mm x 6 mm, the length of the diagonal line is about 8.5 mm, and the minimum size of the circular shape of the light-shielding element 26 that covers the rectangular light-emitting section 24 is a circular shape with a diameter of about 8.5 mm that circumscribes the rectangular shape of the light-emitting section 24. In this case, the area of each light-shielding section 26 is about 57 ^mm2 , and the total area of the light-shielding sections 26 is about 45,240 ^mm2 . Meanwhile, the area of the display substrate 20 is 1066 mm x 546 mm = 582,036 ^mm2 . Therefore, the area of the light-shielding region in the display substrate 20 is about 8% of the total area, and even if the light-shielding section 26 is disposed, the light-transmitting region of the display substrate 20 is about 92%, and visibility from the back surface side of the display is not impaired.

On the other hand, when the area occupied by the light-transmitting regions is 90%, the area of each light-shielding portion 26 is approximately 73 ^mm2 , and the diameter of the light-shielding portion 26 is approximately 10 mm. Therefore, in this example, the size of the light-shielding portion 26 may be appropriately determined so that the area occupied by the light-transmitting regions of the display substrate 20 is in a range of, for example, 90% to 92%, in other words, the area occupied by the light-shielding portion 26 is in a range of, for example, 8% to 10%.

In addition, the size of the light-shielding portion 26 needs to be small to improve visibility from the back side of the display, while the size of the light-shielding portion 26 needs to be large to reduce glare caused by light leaking around the light-shielding portion when viewed from the back side of the display. Therefore, the size (diameter) of the light-shielding portion 26 is determined so that both are appropriate.

Figure 4 is an explanatory diagram showing the support structure of the display unit 18, with a cross-sectional view in Figure 4(A) and an exploded view in Figure 4(B). As shown in Figure 4, the display unit 18 has a translucent support plate 25 made of acrylic resin or the like disposed next to the display substrate 20 on the step on the rear side of the horizontally long display frame 22, and the display substrate 20 and the translucent support plate 25 are assembled and fixed in a stacked state to the display frame 22 by fixing the rear frame member 22a to the rear side of the display frame 22.

The translucent support plate 25 is provided to keep the flexible display substrate 20 in a flat state and to protect it if it is hit by an object. The translucent support plate 25 may be disposed on the display surface side of the display substrate 20, or may be disposed on both sides of the display substrate 20 so as to sandwich the display substrate 20. Furthermore, when the light-emitting display 20 is kept flat by applying tension from all around it using the display frame 22, or when it is held by hanging it vertically, the translucent support plate 25 does not necessarily have to be provided.

[d. Display control unit and controller]
The display control unit 28 and the controller 30 will be described in more detail. As an example, the display control unit 28 operates on a vehicle battery power source, for example, DC 12 V, receives a signal including display information transmitted from the controller 30 by a known wireless communication method, and selectively drives a plurality of light-emitting units 24 arranged in a matrix on the display unit 18 to emit light, and displays, for example, "inspection in progress" by an arrangement of light-emitting points 38 of the light-emitting units 24 that have been driven to emit light, as shown in FIG.

The controller 30 is, for example, portable, used on the driver's seat side, and operates by receiving a supply of DC 12V when the cigarette plug 32 is inserted into the cigarette connector. The controller 30 is provided with a display 34 and an operation unit 36 equipped with various operation switches, etc. Information necessary for the operation and management of roads, such as "under inspection" and "accident ahead, road closed", is registered in advance in the controller 30 , and when the required information is displayed and selected on the display 34 by a predetermined selection operation and a predetermined display start operation is performed after the selection, a signal including the selected display information is wirelessly transmitted to the display control unit 28, and the display unit 18 displays, for example, "under inspection" on the display surface.

In this case, as shown in FIG. 6, the light from the light-emitting unit 24 that is driven to emit light toward the back side of the display unit 18 is blocked by the light-shielding unit 26 to a certain degree, but the light leaking from the light-shielding unit 26 brightens the area around the light-shielding unit 26, and the light-shielding unit 26 appears to stand out in a dark light, and the rear light-emitting points 40 in the rear side of the display unit 18 display information that is a left-right inversion of the currently displayed "Inspection in progress". When the information displayed in a left-right inversion on the rear side of the display unit 18 is reflected, for example, in the rearview mirror 16 shown in FIG. 1, it becomes the currently displayed "Inspection in progress", and the operator of the controller 30 can simply and easily check the information currently displayed on the in-vehicle information display device, rather than checking the information currently displayed on the controller through the rearview mirror 16.

[e. Display substrate]
The display substrate 20 provided in the display unit 18 will now be described in more detail. As an example, Fig. 7 shows the display substrate 20 with some parts omitted. Fig. 8 shows an enlarged view of a part of the display substrate, with Fig. 8(A) showing the display surface side, Fig. 8(B) showing a cross section, and Fig. 8(C) showing the display back side.

As shown in FIG. 8B, the display substrate 20 has a pair of substrates 44, 46 and a resin layer 50 formed between the substrates 44, 46. As shown in FIG. 7, the substrate 44 is a film-like member with its longitudinal direction in the Y direction, and is provided in 80 columns. The substrate 46 is a rectangular film-like member corresponding to the vertical and horizontal sizes of the display unit 18. The substrates 44, 46 are translucent at least to the light emitted by the light-emitting unit. The light transmittance of the substrates 44, 46 is approximately 90%. The substrates 44, 46 are flexible. The substrates 44, 46 may be made of any material, but may be made of, for example, polyethylene terephthalate (PET) or acrylic resin.

A conductor layer 48 is formed on the rear surface of the substrate 44, which is the display rear side. The conductor layer 48 is a metal layer made of a metal material such as copper (Cu) or silver (Ag), and is formed, for example, as a vapor deposition film or a sputtering film.

The light-emitting section 24 is disposed between the substrate 44 and the substrate 46 and is held by the resin layer 50. The resin layer 50 functions as an insulator, and is made of a thermosetting resin or a thermoplastic resin having translucency.

The light-emitting unit 24 is an LED chip (light-emitting diode) that is rectangular with sides of, for example, about 6 mm, and is arranged as a set of red LEDs, green LEDs, and blue LEDs. The cathode side of each LED is commonly connected to the line pattern on the positive side of the conductor layer 48, and the anode side of each LED is connected to an individual line pattern of the conductor layer 48, i.e., the red line pattern, green line pattern, and blue line pattern.

Each line pattern of the conductor layer 48 is pulled out to the outside by a flexible cable 42 shown in FIG. 7 and connected to the display control unit 28 shown in FIG. 1. The display control unit 28 selects each of the red, green, and blue line patterns from each light-emitting unit 24 of the display substrate 20 using a switching element and connects them to the negative line, allowing current to flow through each LED to emit light of a color determined by the ratio of R, G, and B.

As shown in FIG. 8(C), a light-shielding section 26 is arranged on the back surface of the substrate 46, which is disposed on the back surface of the substrate 44, covering the back surface of the substrate at a position opposite the light-emitting section 24. The light-shielding section 26 blocks a predetermined amount of light from the light-emitting section 24 that is driven to emit light toward the back surface of the substrate, and the material of the light-shielding section 26 is arbitrary, and for example, a black-based paint is used. The method of arranging the light-shielding section 46 on the back surface of the substrate 46 is arbitrary, and the light-shielding section 46 is arranged by a known method such as coating, printing, adhesion, lamination, or vapor deposition.

As shown in FIG. 8B, when the light-emitting unit 24 is driven to emit light, the light from the light-emitting unit 24 toward the display surface passes through the substrate 44 as is and is emitted as shown by the arrow a. Here, the light distribution (light distribution characteristics) of the light-emitting unit 24 is approximately circular both in the front and rear, and therefore when viewed from the front, it is seen as a light-emitting point 38 as shown in FIG. 5, and from its arrangement, for example, "Inspection in progress" is seen.

On the other hand, the light traveling backward from the light-emitting portion 24 is blocked by the light-shielding portion 26 arranged on the back surface of the substrate 46. However, as shown by arrow b, some of the light is emitted backward as leaked light from around the light-shielding portion 26. For this reason, when the display substrate 20 is viewed from the back surface side, the black area caused by the light-shielding portion 26 appears to stand out in the bright area caused by the leaked light, and is visually recognized as a back surface light-emitting point 40 as shown in FIG. 6, and the information "Inspection in progress" being displayed on the display surface is visually recognized as a string of characters inverted from left to right.

[f. Light shielding portion]
(f1. Shape of light-shielding part)
The light-shielding portion 26 will be described in more detail. As shown in Fig. 8C, the light-shielding portion 26 has a circular shape that covers the display back side of the light-emitting portion 24, but the shape is arbitrary, and the light-shielding portion 26 may have the same rectangular shape as the light-emitting portion 24, or a polygonal shape having more than one side, or an elliptical shape.

For example, if the light-shielding portion 26 is rectangular, the minimum size of the light-shielding portion 26 is a rectangle with one side measuring 6 mm, the same as the light-emitting portion 24, and in this case, the area of the light-shielding region in the display substrate 20 is 28,800 ^mm2 , which occupies approximately 5%. Also, since the area per light-shielding portion 26 that realizes 90% of the area of the display substrate 20 occupied by the light-transmitting region is 73 ^mm2 as described above, the length of one side of the rectangular light-shielding portion 26 in this case is approximately 8.5 mm. Therefore, in order to make the area of the display substrate 20 occupied by the light-transmitting region 90% to 95% of the area, the size of the light-shielding portion 26 may be appropriately determined within the range of 6 mm to 8.5 mm for the length of one side of the rectangular light-shielding portion 26.

(f2. Adjustment of light blocking degree)
The light shielding portion 46 completely blocks light irradiated from the light emitting portion 24 to the display back side, or blocks the light to a predetermined degree so that the light transmittance is low, and the degree of blocking the light may be adjusted to a predetermined degree. The degree of blocking of the light shielding portion 26 can be adjusted arbitrarily, and can be adjusted, for example, by changing the color density or color of the light shielding portion 26.

Figures 9(A) and (B) show the circular light-shielding portion 26 with different color densities, with the color densities in Figure 9(A) being 100% and Figure 9(B) being 50%. Also, Figures 9(C) to (F) show the light-shielding degree by color densities being, for example, 100%, but by forming the light-shielding portion 26 with circular slit holes 26a, rectangular slit holes 26b, lattice slits 26c, and radial slits 26d, part of the light to be blocked is irradiated to the back side of the display, thereby adjusting the degree of light-shielding.

(f3. Reflective surface of light-shielding part)
10, the surface of the light-shielding portion 26 facing the light-emitting portion 24 may be a reflective surface 27. The material of the light-shielding portion 26 having the reflective surface 27 may be any material having high reflectivity, and for example, a metal film such as aluminum may be used.

When a reflective surface 27 is formed on the light-shielding section 26, the light directed toward the back surface of the display as a result of the light-emitting section 24 being driven to emit light is reflected by the reflective surface 27 and directed forward as indicated by arrow c. By adding to the light directed forward directly from the light-emitting section 24 as indicated by arrow a, the brightness of the light-emitting point as viewed from the display surface can be increased.

(f4. Light shielding portion of liquid crystal structure)
Also, a liquid crystal structure may be used as the light shielding portion 26, as shown in Fig. 11. Here, Fig. 11(A) shows the display surface side, Fig. 11(B) shows a cross section, and Fig. 11(C) shows the display back surface side.

The display substrate 20 shown in FIG. 11 has the same structure as that shown in FIG. 8, but is characterized by the fact that no light-shielding portion 26 is provided on the rear surface of the substrate 46, and instead a light-shielding substrate 52 is provided on which a liquid crystal light-shielding portion 60 is newly provided.

The light-shielding substrate 52 has liquid crystal light-shielding sections 60 held by a resin layer 58 between a pair of light-transmitting glass substrates 54, 56, and arranged in a matrix pattern facing each of the light-emitting sections 24 of the display substrate 20. The liquid crystal light-shielding sections 60 have a known liquid crystal structure, and when no voltage is applied, the light transmittance is at its maximum and transparent. When a voltage is applied, the light transmittance changes according to the applied voltage, and by setting a predetermined light transmittance, it is possible to block all or a predetermined degree of the light traveling from the light-emitting sections 24 to the back side of the display.

In this embodiment, multiple liquid crystal light-shielding sections 60 are arranged on the light-shielding substrate 52, but the light-shielding substrate 52 may be a film or sheet having translucency and flexibility, and the light-shielding section 26 shown in FIG. 8 may be arranged thereon by printing or the like, and this may be laminated on the display back side of the display substrate 20.

[g. Modifications of the present invention]
Modifications of the in-vehicle information display device according to the present invention will be described in more detail below. In addition to the above-described embodiment, the in-vehicle information display device according to the present invention includes the following modifications.

(Light-emitting part and light-shielding part)
The dimensions of the light-emitting portion in the above embodiment are merely examples, and a light-shielding portion of an appropriate size and shape for shading the light-emitting portion may be adopted according to the size and shape of the light-emitting portion. In addition, the light-shielding portion is preferably larger than the light-emitting portion in order to shade the entire light-emitting portion, but in cases where it is not necessary to completely shade the entire light-emitting portion, such as to prevent glare due to leaked light from adversely affecting the viewer, the light-shielding portion may be large enough to shade most of the light-emitting portion, for example, 90% or more.

(Split structure of display section)
In the above embodiment, the display substrate 20 is a single sheet size corresponding to the vertical and horizontal sizes of the display section 18, and has 800 pixels with the light-emitting sections 24 arranged in a matrix of 20 rows and 40 columns, but this is not limited to this and the display substrate 20 may be divided into smaller sizes. For example, one display substrate 20 has 400 pixels with the light-emitting sections 24 arranged in a matrix of 20 rows and 20 columns with a pixel pitch of 26 mm, which makes it possible to display one character. In this case, the vertical and horizontal sizes of the display substrate 20 are 546 mm x 546 mm, and the display section 18 may be configured by arranging a plurality of such substrates.

(Arrangement of light-shielding parts)
In the above-described embodiment, the light-shielding portion is disposed on the back surface of the display substrate 20 that corresponds to the display back surface side, or the back surface of the light-shielding substrate 52 that corresponds to the display back surface side, but this is not limited thereto, and it may be disposed on the display back surface side of the light-emitting portion 24 in a position where it can completely block light irradiated to the display back surface side, or can block light to a predetermined degree so as to reduce light transmittance.

(Curved arrangement)
In the above embodiment, since the display substrate 20 and the light-shielding substrate 52 are flexible, the in-vehicle information display device may be installed in a curved state rather than being kept in a flat state. The ability to be curved allows the in-vehicle information display device to be installed in accordance with the structure of the installation location.

(Loading the vehicle)
In the above embodiment, the in-vehicle information display device is installed in a position that is visible from the rear of the vehicle through the rear window of the passenger compartment, but this is not limited to this, and the in-vehicle information display device may be installed in a position that is visible from outside the vehicle through a passenger compartment window other than the rear window.

(non-vehicle use)
The above embodiment is an example of a case where the on-board information display device is installed in a vehicle used for road operation and management, but is not limited to this and includes any suitable moving body. Furthermore, it is not limited to a moving body such as a vehicle, and includes a case where the device is installed in a position visible from outside the building through an indoor window.

(others)
Furthermore, the present invention is not limited to the above-described embodiment, but includes appropriate modifications that do not impair the objects and advantages of the present invention, and is not limited to the numerical values shown in the above-described embodiment.

10: In-vehicle information display device 12: Vehicle 14: Rear window 16: Rearview mirror 18: Display unit 20: Display substrate 22: Display frame 22a: Rear frame member 24: Light-emitting unit 25: Light-transmitting support plate 26: Light-shielding unit 26a: Circular slit hole 26b: Rectangular slit hole 26c: Lattice slit 26d: Radiating slit 27: Reflecting surface 28: Display control unit 30: Controller 32: Cigarette lighter plug 34: Display 36: Operation unit 38: Light-emitting point 40: Back light-emitting point 42: Flexible cable 44, 46: Substrate 48: Conductive layer 50, 58: Resin layer 52: Light-shielding substrate 54, 56: Glass substrate 60: Liquid crystal light-shielding unit

Claims (10)

An in-vehicle information display device that displays predetermined information on a display surface so as to be visible from outside the vehicle,
a plurality of light-emitting sections disposed on a light-transmitting display substrate and configured to emit light in two directions, that is, toward the display surface and toward an opposite surface of the display substrate;
a plurality of light-shielding sections that are arranged on a display back surface side that is the opposite surface side corresponding to the positions of the plurality of light-emitting sections and that block light emitted from the plurality of light-emitting sections at the positions where the light-emitting sections are arranged to the display back surface side ;
Equipped with
the plurality of light-emitting sections form backside light-emitting points at which leakage light from the plurality of light-shielding sections to the display backside when the light-emitting sections emit light makes the periphery of the plurality of light-shielding sections appear brighter than the light-shielding sections when viewed from the display backside,
An in-vehicle information display device characterized in that the multiple light-shielding portions are arranged so that the information displayed on the display surface can be viewed from the back surface side of the display due to the arrangement of the back light-emitting points.
An in-vehicle information display device that displays predetermined information on a display surface so as to be visible from outside the vehicle,
a plurality of light-emitting sections disposed on a light-transmitting display substrate and configured to emit light in two directions, that is, toward the display surface and toward an opposite surface of the display substrate;
a display unit that displays the information on the display surface by selectively driving the light- emitting units, the light-emitting units being arranged in a matrix at a predetermined interval such that the information can be viewed when the light-emitting unit is moved away from the display unit by a predetermined distance or more;
a plurality of light-shielding sections that are arranged on a display back surface side that is the opposite surface side corresponding to the positions of the plurality of light-emitting sections and that block light emitted from the plurality of light-emitting sections at the positions where the light -emitting sections are arranged to the display back surface side;
Equipped with
the display unit forms back-side light-emitting points at which the periphery of the plurality of light -shielding parts is visually recognized as brighter than the light-shielding parts when viewed from the back side of the display unit due to leakage light from the plurality of light-shielding parts to the back side of the display unit when the plurality of light-emitting parts are driven to emit light,
An in-vehicle information display device characterized in that the multiple light-shielding portions are arranged so that the information displayed on the display surface can be viewed from the back surface side of the display due to the arrangement of the back light-emitting points.
3. The in-vehicle information display device according to claim 1,
This vehicle-mounted information display device is characterized in that information generated by an arrangement of rear-side light-emitting points, which is left and right inverted when viewed from the rear side of the display, is reflected by a rearview mirror and further inverted left and right, and is installed in a position where it can be seen in the same way as when viewed from the display surface side.
4. The in-vehicle information display device according to claim 1,
1. An in-vehicle information display device that is installed in a position visible from the rear of a vehicle through a rear window of a vehicle compartment.
5. The in-vehicle information display device according to claim 1,
The vehicle-mounted information display device according to claim 1, wherein the light-shielding portion has a reflective surface facing the light-emitting portion.
6. The in-vehicle information display device according to claim 1,
An in-vehicle information display device characterized in that the degree to which the light-shielding portion blocks light traveling from the light-emitting portion to the back surface of the display is adjusted to a predetermined degree by adjusting the color density or by forming a slit of a predetermined shape that does not block light .
7. The in-vehicle information display device according to claim 1,
An in-vehicle information display device, characterized in that a light-transmitting light-shielding substrate body is provided on the display back side of the display substrate body, and the light-shielding portions are arranged corresponding to the positions of each of the light-emitting portions.
The in-vehicle information display device according to claim 7,
An in-vehicle information display device characterized in that the light-shielding portion arranged on the light-shielding substrate has a liquid crystal structure in which the light transmittance is maximum when no voltage is applied, and when a voltage is applied, the light transmittance changes depending on the applied voltage.
9. The in-vehicle display information device according to claim 1,
The light-emitting unit includes light-emitting portions that emit light in the three primary colors, and each light-emitting portion independently emits light in a predetermined color.
10. The in-vehicle information display device according to claim 1,
The in-vehicle information display device is characterized in that the display substrate, or, when a light-shielding substrate is provided, the display substrate and the light-shielding substrate have flexibility.

Images