JP2015049994A - Light reflection type display device and vehicular lighting fixture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light reflection type display device which can selectively form a various display patterns, and to provide a thin vehicular lighting fixture equipped therewith.SOLUTION: A light reflection type display device 1 includes a light guide 2, an LED light source 3, electronic paper 4, and a controller 5. The light guide 2 is plate-shaped. Visible light from the LED light source 3 enters from a peripheral face 2c of the light guide 2 to the inside. The electronic paper 4 is arranged on the side of a reverse 2b of the light guide 2, where a light reflection part 4a is formed by the aggregation of charged particles whose bright parts are directed to the side of the light guide 2 and a light absorption part 4b is formed by the aggregation of charged particles whose dark parts are directed to the side of the light guide 2, when energized. The controller 5 changes over the electric charges of the charged particles to change the shapes of the light reflection part 4a and the light absorption part 4b, and with the light reflection part 4a and the light absorption part 4b combined, the electronic paper 4 displays various kinds of images 7 on a surface 2a of the light guide 2.

Description

  The present invention relates to a light reflection display device that displays light using reflected light by reflecting light extracted from a light guide at a light reflection portion, and a vehicle lamp including the display device.

  As a light reflection type device of this type, conventionally, light from a light source is incident on the inner surface of the light guide and taken out from the rear surface of the light guide. A technique for entering and emitting from the surface of a light guide is known. For example, in the apparatus 51 shown in FIG. 6A, an LED light source 53 is arranged around the light guide 52, a step 54 is engraved on the back surface of the light guide 52, and the light from the LED light source 53 is step 54. And is emitted from the surface of the light guide 52. In the apparatus 61 shown in FIG. 6B, a diffusion sheet or vapor deposition sheet 62 as a light reflecting portion is provided on the back surface side of the light guide 63.

  Patent Document 1 describes a vehicular lamp that uses an electro-optic element having a dimming function in a light-blocking portion that blocks light from a light source, and variably controls a light distribution pattern in front of the vehicle. Patent Document 2 describes a vehicular lamp that collects and emits diffused light from an organic EL with a reflecting mirror.

JP 2005-183327 A JP 2011-150887 A

  However, according to the conventional light reflection type devices 51 and 61, since the light emission pattern of the light guides 52 and 63 does not change, there is a problem that display contents are limited when used as a display device. Further, the vehicular lamp described in Patent Documents 1 and 2 can change the light distribution pattern by electrically controlling the light emitting element, but when the vehicular lamp is desired to function as a display device, There is a problem that the depth of the lamp, that is, the distance from the light source to the display surface becomes long.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a light reflection type display device capable of selectively forming various display patterns, and a thin vehicle lamp equipped with this device.

In order to solve the above-mentioned problems, the present invention provides the following light reflection type display device and vehicle lamp.
(1) A light guide having a front surface, a back surface, and a peripheral surface, a light source that enters light from the peripheral surface into the light guide, and light that reflects light emitted from the back surface of the light guide to the front side of the light guide A light reflection type display device, comprising: electronic paper including a reflection portion; and a controller that electrically changes a shape of the light reflection portion.

(2) The electronic paper includes a light absorbing part that absorbs light more easily than the light reflecting part, and displays an image on the surface of the light guide by a combination of the light absorbing part and the light reflecting part. The light reflection type display device described in 1.

(3) The light reflective display device as described in 1 or 2 above, wherein a transparent layer containing light scattering particles is provided between the light guide and the electronic paper.

(4) A vehicular lamp comprising means for attaching the light reflecting display device according to any one of the above items 1 to 3 to a vehicle body.

(5) The vehicular lamp as described in (4) above, wherein the light guide and the electronic paper of the light reflection type display device are curved along the mounting surface on the vehicle body side.

  According to the light reflection type display device of the present invention, the light emitted from the back surface of the light guide is reflected by the light reflection portion of the electronic paper. Therefore, by electrically controlling the shape of the light reflection portion, the light guide There is an effect that various display patterns can be selectively formed on the surface of the substrate. Further, according to the vehicular lamp of the present invention, since the distance from the light source to the display surface is shortened, there is an effect that the entire lamp can be configured to be thin.

It is a perspective view of the light reflection type display which shows one Embodiment of this invention. It is a perspective view of the light reflection type display apparatus which shows the change of a display pattern. It is sectional drawing which shows the joining structure of a light guide and electronic paper. It is a side view of the vehicle which shows the vehicle lamp provided with the light reflection type display apparatus. It is sectional drawing of the vehicle lamp along the VV line | wire of FIG. It is a perspective view which shows the conventional light reflection type | mold apparatus.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. A light reflection type display device 1 shown in FIG. 1 includes a light guide 2, an LED light source 3, electronic paper 4, and a controller 5. The light guide 2 is formed in a plate shape having a front surface 2a, a back surface 2b, and a peripheral surface 2c using a transparent material. The LED light sources 3 are arranged so that the required number faces the peripheral surface 2c of the light guide 2, and allows visible light to enter the inside of the light guide 2 from the peripheral surface 2c. The electronic paper 4 is disposed on the back surface 2 b side of the light guide 2, and is connected to the controller 5 through the electric wiring 6 together with the LED light source 3. The LED light source 3 may employ light emitting elements that generate light of a plurality of colors, such as RGB (red, green, blue) / yellow, in addition to light emitting elements that generate light of a single color.

  The electronic paper 4 includes a large number of charged particles having a light color portion that easily reflects light and a dark color portion that easily absorbs light. At the time of energization, the light reflecting portion 4a is formed by an aggregate of charged particles with the bright color portion facing the light guide 2 side, and the light absorbing portion 4b is formed by the aggregate of charged particles with the dark color portion facing the light guide 2 side. Is formed. And the controller 5 changes the shape of the light reflection part 4a and the light absorption part 4b by switching the electric charge of a charged particle, and the electronic paper 4 is the surface of the light guide 2 by the combination of the light reflection part 4a and the light absorption part 4b. An arbitrary image 7 is displayed on 2a.

  For example, the image 7 shown in FIG. 1 includes a “Koito” logo that the light reflecting portion 4a displays in white and a background that the light absorbing portion 4b displays in black. Further, the image 17 shown in FIG. 2 includes a logo that the light absorbing unit 4b displays in black and a background that the light reflecting unit 4a displays in white. The display method of the electronic paper 4 is not particularly limited. For example, an electrophoretic method suitable for black and white display, a cholesteric liquid crystal method capable of color display, or a chemical change method using an organic or inorganic redox reaction. Etc. can be adopted.

  As shown in FIG. 3, the electronic paper 4 is held by the retainer 8 so as to overlap the light guide 2. In the display device 1A shown in FIG. 3A, a slit 9 is provided between the light guide 2 and the electronic paper 4, and the periphery of the slit 9 is sealed by a retainer 8 so that moisture does not enter. . In the display device 1 </ b> B shown in FIG. 3B, a transparent layer 10 containing light scattering particles is interposed between the light guide 2 and the electronic paper 4. The transparent layer 10 allows the reflected light from the light reflecting part to be incident on the inside of the light guide 2 without fail, so that the light utilization efficiency of the electronic paper 4 can be improved, and the image 7 is captured by the scattered light generated by the light scattering particles. Can be decorated.

  In the light reflection type display device 1 having the above configuration, when the LED light source 3 and the electronic paper 4 are energized, light from the light source 3 enters the inside from the peripheral surface of the light guide 2, and the back surface 2 b of the light guide 2. Then, the light is reflected by the light reflecting portion 4a of the electronic paper 4, and the reflected light reenters the light guide 2 from the back surface 2b to display the image 7 on the front surface 2a. Since the image 7 can be arbitrarily changed by electrically controlling the shapes of the light reflecting portion 4a and the light absorbing portion 4B by the controller 5, various display patterns can be formed according to the use of the display device 1. Further, since the electronic paper 4 self-holds the display content even after the energization is stopped, the display device 1 can be operated economically with low power consumption.

  FIG. 4 shows a vehicular lamp 21 provided with the display device 1 having the above-described configuration. This vehicular lamp 21 functions as a display panel of an automobile, and selectively displays, for example, a plurality of types of characters 23 such as “XX TAXI”, “rental”, “empty car” on the outer surface of the door panel 22. As shown in FIG. 5, the body 24 of the vehicle lamp 21 is attached to the door panel 22 by means 25 such as screws or clips, and the outer surface of the body 24 is covered with a transparent waterproof cover 26.

  The light guide 2, the electronic paper 4, and the transparent layer 10 of the light reflection type display device 1 are each curvedly formed along the outer surface (mounting surface of the vehicle body) of the door panel 22, and the surface 2 a of the light guide 2 extends outside the vehicle body. It is held by the body 24 by the retainer 8 so as to face. According to the vehicular lamp 21, since the surface 2a of the light guide 2 is used as a display surface and the LED light source 3 is disposed opposite to the peripheral surface of the light guide 2, the distance from the light source 3 to the display surface 2a is increased. There is an advantage that it can be shortened and the entire lamp can be made thin.

The vehicular lamp 21 of the present invention is not limited to the embodiment shown in FIG. 4 and can be implemented in the following manner.
(1) The vehicle lamp 21 is mounted rearward on the inner surface of the rear window, and is disposed so as to irradiate light to the rear of the vehicle through the rear window.
(2) The light reflecting portion 4a of the electronic paper 4 is formed so that the vehicular lamp 21 not only displays the characters 23 but also displays a pattern emitting light from a predetermined area or the entire surface.
(3) Apply the vehicular lamp 21 to a marker lamp such as a tail lamp, a stop lamp, a turn signal lamp, a backup lamp, or a clearance lamp (vehicle width lamp).

  The light reflection type display device 1 of the present invention is not limited to the vehicular lamp 21. For example, an indicator lamp indicating an “emergency exit” of a building, a display board for informing the operation status of a train or a bus, and a route map in the vehicle. It can be applied to a guidance device for displaying a destination, a road sign, an advertisement indicator lamp, and the like. In addition, the present invention is not limited to the above-described embodiment, and can be carried out by appropriately changing the shape and configuration of each part without departing from the spirit of the invention.

DESCRIPTION OF SYMBOLS 1 Light reflection type display apparatus 2 Light guide 2a Front surface 2b Back surface 2c Circumferential surface 3 LED light source 4 Electronic paper 4a Light reflection part 4b Light absorption part 5 Controller 7 Image 8 Retainer 9 Narrow gap 10 Transparent layer 21 with light scattering particles 21 For vehicles Lamp

Claims (5)

  A light guide having a front surface, a back surface, and a peripheral surface; a light source for introducing light into the light guide from the peripheral surface; and a light reflecting portion for reflecting light emitted from the back surface of the light guide to the front surface side of the light guide A light reflection type display device comprising: an electronic paper provided; and a controller that electrically changes a shape of the light reflection portion.   The light reflecting display according to claim 1, wherein the electronic paper includes a light absorbing portion that absorbs light more easily than the light reflecting portion, and displays an image on the surface of the light guide by a combination of the light absorbing portion and the light reflecting portion. apparatus.   The light reflection type display device according to claim 1, further comprising a transparent layer containing light scattering particles between the light guide and the electronic paper.   A vehicle lamp, comprising means for attaching the light reflection type display device according to any one of claims 1 to 3 to a vehicle body.   The vehicular lamp according to claim 4, wherein the light guide body and the electronic paper of the light reflection type display device are curved along the mounting surface on the vehicle body side.

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