JPH1090015A - Meter for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a meter which can restrict the attenuation of light due to the reflection at a light guide plate thereby to secure a required quantity of light for a transmission illumination of a display part of a character plate arranged in front of the light guide plate, etc., and uniform the quantity of light all over the character plate. SOLUTION: Light of a light source 5 brought into a light guide plate 7 from an upper end face 7c of the light guide plate 7 arranged behind a character plate 3 is, while reflected at a front face 7a, a backside 7b, both side end faces and a lower end face 7e of the light guide plate 7, guided within the light guide plate 7. The light is projected to the character plate 3 from a position of the front face 7a confronting a display part 3d of the character plate 3, and passed through a base plate 3a of the character plate 3, a slit 3e of a black prohibition layer 3c and a white transmission layer 3b, thereby to illuminate the display part 3d. A surface layer part 9a of a light reflection layer 9 is formed at a part of the front face 7a of the light guide plate 7 except a part facing the display part 3d so as to reflect the light projected to the part of the front face 7a to the interior of the light guide plate 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, a light guide plate disposed behind a dial of an instrument for displaying a running speed of a vehicle, which guides light for illuminating the instrument, and using the light, a display portion of the dial. The present invention relates to a vehicle instrument for transmitting illumination from behind.

[0002]

2. Description of the Related Art For example, in an instrument for displaying a running speed of a vehicle, a dial is composed of a transparent base material, a white light diffusion layer formed on the surface of the base material, and a light diffusion layer. By means of, for example, a black light-shielding layer formed on a portion other than a portion constituting a display portion such as a scale or a symbol of a dial, a display portion is formed without a translucent design, and disposed behind the dial. Light guided from the light source through the light guide plate is applied to the dial from behind the display unit, and the display unit is transmitted and illuminated by the light transmitted to the front side of the dial plate.

In such an instrument, light guided inside the light guide plate while being reflected on the front and back surfaces of the light guide plate leaks outward from the back surface of the light guide plate opposite to the dial side, and the amount of light decreases. The light guide plate is covered with a white light-diffusing layer to prevent light from being distributed evenly in the light guide plate and to prevent the amount of transmitted illumination of the display unit at different locations on the dial plate from fluctuating. The light applied to the back surface of the light guide plate is diffused and reflected inside the light guide plate, and the light reflected and diffused on the back surface side of the light guide plate and applied to the surface of the light guide plate facing the display unit. However, the surface of the light guide plate facing the display unit is subjected to a diffusion grain (or satin finish) process so that the display unit is transmitted and illuminated with a larger amount of light.

[0004]

However, in the above-described conventional vehicle instrument, the light emitted from the surface portion of the light guide plate other than the portion facing the display unit and irradiated on the dial is not covered by the base material. The light is transmitted through the inside from the back surface to the light diffusion layer on the substrate surface, and furthermore, the light transmitted through the light diffusion layer is irradiated on the light shielding layer, and the light is totally reflected by the light shielding layer toward the light guide plate. This is not the case, but part of the light is absorbed by the light-shielding layer, and the amount of light is reduced. This reduction in the amount of light makes it impossible to secure the required amount of illumination for the display unit.

The above problem is not limited to the above-described case in which light is guided by the light guide plate behind the dial for transmitted illumination of the display portion of the dial, but the light guided by the light guide plate behind the dial. Is reflected at the back surface of the light guide plate facing the dial portion where the pointer hakama of the pointer placed in front of the dial is inserted, and illuminates the pointer through the dial portion where the pointer hakama is inserted, The same phenomenon occurs when the light enters the interior of the pointer body from the light incident surface of the transparent pointer body to shine the pointer body.

In particular, in the case of transmitting illumination of the display portion of the dial, in a conventional vehicle instrument, the light in the light guide plate is attenuated as the reflection on the dial side repeats, so that the light is attenuated. The amount of light when the display portion of the near dial portion is illuminated by transmission and the amount of light when the display portion of the dial portion distant from the light source is illuminated by transmission vary, and the entire display unit has a uniform light amount. There is a problem that the transmitted illumination cannot be performed.

[0007] The present invention has been made in view of the above circumstances,
An object of the present invention is to provide a scale for a dial in a vehicle instrument,
Reflection of light from a light source used as transmitted light for a display part such as a sign and illumination light of a self-luminous type pointer for indicating the display part on the back surface of the light guide plate, and the back surface part of the dial facing the display unit. In addition, when the light is incident on the back side of the dial facing the light incident surface of the pointer body, the attenuation of the light due to the reflection on the light guide plate is suppressed, and the amount of light required for illumination is secured and the entire dial is It is an object of the present invention to provide an instrument for a vehicle which can make the light amount uniform over the vehicle.

[0008]

According to a first aspect of the present invention, there is provided an instrument for a vehicle according to the present invention, wherein a light guide plate is provided behind a dial plate, and a surface of the light guide plate and the character plate are arranged. The light is incident from the peripheral end surface of the light guide plate and guided inside the light guide plate, and the light emitted from the front surface of the light guide plate and applied to the back surface of the dial is referred to as the letter. In a vehicle instrument for transmitting light to the surface side of the plate and illuminating the illuminated member arranged on the surface side of the dial with the light,
The light guide plate is provided on one of the back surface of the dial and the surface of the light guide plate, except for at least a portion corresponding to a surface portion facing the illuminated member on the surface of the dial plate, A light reflecting member for reflecting light emitted from the surface of the light plate toward the inside of the light guide plate is provided.

According to a second aspect of the present invention, in the vehicle instrument of the present invention, the light reflecting member is disposed on a surface of the light guide plate.
A light reflecting member for a back surface is provided on the back surface of the light guide plate to reflect light emitted from the back surface toward the inside of the light guide plate.

Further, in the vehicle instrument according to the present invention, at least a part of the peripheral end surface portion of the light guide plate except for the peripheral end surface portion where the light is incident is provided. A light reflecting member for a peripheral end face is provided which communicates a reflecting member with the light reflecting member for the back surface and reflects light emitted from at least a part of the peripheral end face portion toward the inside of the light guide plate. The light reflecting member, the light reflecting member for the back surface, and the light reflecting member for the peripheral end surface are integrally formed by a light guide plate housing member in which the light guide plate is housed, and the light guide plate housing member With the light guide plate housed,
An opening for exposing at least a portion of the peripheral end surface of the light guide plate where the light is incident to the outside of the light guide plate accommodation member is provided in the light guide plate accommodation member in a size that allows the light guide plate to be taken in and out. It was taken.

According to a fourth aspect of the present invention, in the vehicle instrument according to the present invention, the peripheral end surface of the light guide plate extends over the entire peripheral end surface portion except for the peripheral end surface portion where the light is incident. A light reflecting member for a peripheral end surface that reflects light emitted from the portion toward the inside of the light guide plate is provided.

According to the first aspect of the present invention, of the light reflected on the back surface of the light guide plate, the dial is transmitted from the back surface side to the front surface side to be guided to the member to be illuminated for illumination. The optical path of the other light except the optical path of the light that needs to be used is blocked by a light reflecting member formed on one of the back surface of the dial and the surface of the light guide plate, and directed toward the inside of the light guide plate. Since the light is reflected, light in the optical path not used for illuminating the illuminated member is prevented from being emitted from the light guide plate and absorbed and attenuated when illuminating the dial, and the light amount required for illuminating the illuminated member is secured. In addition, it is possible to prevent the variation of the illumination light amount due to the difference in the position of the illuminated member in the direction along the front and back surfaces of the dial.

Further, according to the vehicle instrument of the present invention, when the light guided inside the light guide plate reaches the back surface of the light guide plate, the light for the back surface formed on the back surface. Since the light is reflected toward the inside of the light guide plate by the reflection member, that is, toward the front surface side of the light guide plate, it is necessary to emit the light to the dial side on the back surface of the light guide plate for illumination of the illuminated member. It is possible to prevent light other than the light path of the light from being emitted to the outside of the light guide plate and leak, and to more reliably prevent attenuation of light guided in the light guide plate.

Further, according to the vehicle instrument of the present invention, the light guide plate is housed inside the light guide plate housing member from the open portion, so that the front and back surfaces of the light guide plate and the periphery of the light guide plate can be accommodated. Since the light reflecting member, the back surface light reflecting member, and the light reflecting member for the peripheral end surface are respectively provided at least in part of the peripheral end surface portion except the peripheral end surface portion where light is incident on the end surface. In addition, it is possible to easily arrange the corresponding light reflecting members on each surface of the light guide plate, and to guide the light reflecting members from the peripheral end surface portion of the light guide plate on which the peripheral end surface light reflecting member is arranged. Light emission to the outside of the light plate and leakage of light can be prevented, so that attenuation of light guided in the light guide plate can be more reliably prevented.

Further, according to the vehicle instrument of the present invention, the light guided inside the light guide plate reaches the peripheral end surface portion excluding the peripheral end surface where the light of the light guide plate is incident. In this case, since the light is reflected toward the inside of the light guide plate by the light reflecting member for the peripheral end surface formed on the peripheral end surface portion, the entire peripheral end surface portion except for the peripheral end surface portion where the light of the light guide plate is incident. In, to prevent the light other than the optical path of the light that needs to be emitted to the dial side for illumination of the illuminated member is emitted to the outside of the light guide plate and leaks, the attenuation of light guided in the light guide plate is reduced. It is possible to further increase the certainty of prevention.

When the vehicle meter of the present invention described in claim 4 is applied to the vehicle meter of the present invention described in claim 3, the light guide plate housing member receives light from the light guide plate. The light reflecting member and the back surface light reflecting member are connected to each other by the light reflecting member for the circumferential end surface over the entire peripheral end surface portion except for the peripheral end surface portion to be formed.

[0017]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a vehicle instrument according to an embodiment of the present invention.

First, a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view of a vehicle instrument according to a first embodiment of the present invention. The vehicle instrument according to this embodiment, which is denoted by reference numeral 1 in FIG. A light guide plate 7 for guiding illumination light for the dial 3 from the light source 5 and an illumination light from the light source 5 guided inside the light guide plate 7 for preventing the illumination light from being emitted to the outside of the light guide plate 7; And a light reflection layer 9 for reflection.

The dial 3 covers the surface of a transparent substrate 3a with a white light-transmitting layer 3b, and places a display portion 3d such as a scale or a symbol (corresponding to a member to be illuminated) on the white light-transmitting layer 3b. ) Is formed by covering with a black impermeable layer 3c in which a slit 3e without design corresponding to (3) is formed. The light guide plate 7 is formed of a translucent member such as a transparent synthetic resin and has substantially the same outer shape as the dial plate 3. The front surface 7 a of the light guide plate 7 is the dial plate 3 and the back surface of the substrate 3 a. The light source 5 made of, for example, a fluorescent tube or the like is arranged above the light guide plate 7 as shown in FIG.

In addition, reference numeral 7b in FIG. 1 denotes a back surface of the light guide plate 7, reference numeral 7c in FIGS. 1 and 2 denotes an upper end surface of the light guide plate 7 (corresponding to a peripheral end surface where light of the light guide plate is incident), In FIG. 2, reference numerals 7d and 7d denote side end surfaces of the light guide plate 7, and 7e denotes a lower end surface of the light guide plate 7, respectively. Further, in the present embodiment, the back surface of the substrate 3a corresponds to the back surface of the dial 3, and the upper end surface 7c, the side end surfaces 7d, 7d, and the lower end surface 7e of the light guide plate 7 define a peripheral portion of the light guide plate. End faces are formed, and among these, the side end faces 7d, 7d and the lower end face 7e correspond to the peripheral end face portions excluding the peripheral end face portions of the light guide plate where light is incident.

As shown in FIG. 1, the light reflection layer 9 includes a surface layer 9a (corresponding to a light reflection member) covering the front surface 7a of the light guide plate 7, and a back layer covering the back surface 7b of the light guide plate 7. Part 9b
(Corresponding to a light reflecting member for the back surface) and, as shown in FIG. 2, side layer portions 9d, 9d covering the respective side end surfaces 7d, 7d of the light guide plate 7.
And a lower layer portion 9e that covers the lower end surface 7e of the light guide plate 7. In the present embodiment, each of the layer portions 9a, 9b, 9d,
9e, corresponding surfaces 7a, 7b, 7d, 7e of the light guide plate 7
The surface to be applied to the surface of the light guide plate 7 is, for example, formed of a mirror-finished, relatively thin synthetic resin material or the like that enables total reflection of light. The back surface of the substrate 3a of the dial 3 is applied to the portion 9a.

Then, in the surface layer 9a of the light reflection layer 9,
The surface layer 9a corresponding to the surface 7a of the light guide plate 7 facing the display portion 3d of the dial 3 (corresponding to the surface of the light guide plate corresponding to the surface of the dial facing the illuminated member) includes:
A slit 9c for transmitting light from the light guide plate 7 to the dial 3 side is formed, and the side layer portions 9d, 9d and the lower layer portion 9e constitute a light reflection member for a peripheral end surface in the claims. .

Next, in the vehicle instrument 1 of the first embodiment configured as described above, in particular, the dial 3
The operation when the display unit 3d is transmitted and illuminated will be described.

When the light source 5 is turned on and light is emitted from the outer periphery, light enters the interior of the light guide plate 7 located below the light source 5 from the upper end surface 7c thereof. Surface 7a, the back surface 7b, both end surfaces 7d, 7d, and the lower end surface 7e directly or indirectly reflected by other surfaces. Then, the back surface 7b of the light guide plate 7, both end surfaces 7d, 7
d and the light that has reached the lower end surface 7e is reflected on the mirror-finished surfaces of the back layer 9b, the side layers 9d, 9d of the light reflecting layer 9 covering the respective surfaces, and the lower layer 9e. 7
It is totally reflected toward the inside of.

The light source 5 reaches the surface 7a of the dial 3 except for the portion facing the display 3d of the dial 3 on the surface 7a of the light guide plate 7.
Is totally reflected toward the inside of the light guide plate 7 on the mirror-finished surface of the surface layer portion 9a of the light reflection layer 9 covering the surface 7a. On the other hand, the light from the light source 5 that reaches the surface 7a of the surface 3a of the light guide plate 7 facing the display portion 3d of the dial 3 is formed on the surface layer 9a of the light reflecting layer 9 corresponding to the surface 7a. After exiting the light guide plate 7 through the slit 9c and transmitting from the back surface to the front surface of the substrate 3a,
The light enters the white light-transmitting layer 3b, passes through the white light-transmitting layer 3b, and further exits through the slit 3e of the black non-transmissive layer 3c to the front of the dial 3, and the light transmits through the display unit 3d. Lighting is provided.

As described above, according to the vehicle instrument 1 of the first embodiment, the upper end surface 7 of the light guide plate 7 disposed behind the dial 3
c, the light from the light source 5 incident on the inside of the light guide plate 7 is guided inside the light guide plate 7 while being reflected by the front surface 7a and the back surface 7b of the light guide plate 7, both end surfaces 7d, 7d, and the lower end surface 7e. The light is emitted toward the dial 3 from the surface 7a facing the display portion 3d of the dial 3, and transmitted through the substrate 3a of the dial 3, the slit 3e of the black impermeable layer 3c, and the white translucent layer 3b. When transmitting and illuminating the display unit 3d, light that irradiates the surface 7a of the light guide plate 7 excluding a portion facing the display unit 3d with the light applied to the surface 7a is reflected toward the inside of the light guide plate 7. The surface layer 9a of the reflection layer 9 was formed.

For this reason, light is emitted from the surface 7a of the light guide plate 7 except for the portion facing the display portion 3d of the dial 3 toward the dial 3 and transmits through the substrate 3a to reach the black impermeable layer 3c. Then, light that is absorbed without being reflected by the black impermeable layer 3c is generated, and the amount of light guided inside the light guide plate 7 is reduced.
It is possible to prevent the amount of light required for the transmitted illumination of the display unit 3d from not being secured.

The surface layer 9a is formed on the surface 7a of the light guide plate 7 except for the portion facing the display portion 3d of the dial 3, so that each time the surface 7a is irradiated with light, the above-mentioned black color is obtained. A decrease in the amount of light due to irradiation on the non-transmissive layer 3c is prevented, so that, when a plurality of display portions 3d are formed on the dial 3, from the upper end surface 7c where light from the light source 5 is incident. It is possible to prevent the light quantity of the light from decreasing as the light guide plate reaches seven locations farther apart, and to prevent the light quantity of the transmitted illumination from varying between the display units 3d.

Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a cross-sectional view of a vehicle instrument according to a second embodiment of the present invention. The vehicle instrument according to the present embodiment, which is denoted by reference numeral 1A in FIG. 3, has the same characters as the vehicle instrument 1 according to the first embodiment. The plate 3, the light source 5, and the light guide plate 7, and the light guide plate 7 is accommodated therein, and the illumination light from the light source 5 guided inside the light guide plate 7 is prevented from being emitted to the outside of the light guide plate 7. And a light guide plate housing member 11 different from the light reflection layer 9 in the vehicle instrument 1 of the first embodiment.

As shown in the perspective view of FIG. 4, the light guide plate accommodating member 11 is formed of, for example, a relatively thin synthetic resin material, and an insertion opening into which the light guide plate 7 is inserted from the lower end surface 7e side. 11f (corresponding to an open portion). Then, the light guide plate housing member 11 is inserted and housed in the light guide plate housing member 11 from the insertion opening 11f.
A front wall portion 11a (corresponding to a light reflecting member) covering the front surface 7a of the light guide plate 7, and a back wall portion 11b covering the back surface 7b of the light guide plate 7
(Corresponding to a light reflecting member for the back surface), and each side end surface 7 of the light guide plate 7
d, 7d, and a lower wall 11e covering the lower end surface 7e of the light guide plate 7, as shown in FIG. 3, and in this embodiment, the light guide plate 7 is accommodated. In this state, the inner surfaces of the walls 11a, 11b, 11d, and 11e that come into contact with the surfaces 7a, 7b, 7d, and 7e of the light guide plate 7,
It is mirror-finished to allow total reflection of light.

The light guide plate housing member 11 configured as described above
In the state where the light guide plate 7 is inserted and accommodated therein, as shown in FIG. 3, the dial plate 3 and the light guide plate 7 are arranged such that the outer surface of the front wall portion 11a comes into contact with the back surface of the substrate 3a of the dial plate 3. In this state, the light guide plate 7 is provided on the surface 11a of the light guide plate housing member 11 facing the display 3d of the dial 3.
11 that allows light to pass from the dial to the dial 3 side
c is formed, and the side wall portions 11d, 11d and the lower wall portion 1 are formed.
1e constitutes the peripheral end face light reflecting member in the claims.

In the thus configured vehicle instrument 1A of the second embodiment, similarly to the vehicle instrument 1 of the first embodiment, the light emitted from the outer periphery of the light source 5 when the light source 5 is turned on is transmitted to the light guide plate. The light enters the inside of the light guide plate 7 from the upper end surface 7c through the insertion opening 11f of the housing member 11, and the rear surface 7b of the light guide plate 7
When the light reaches the both end surfaces 7d, 7d and the lower end surface 7e directly or indirectly after being reflected by another surface, the back wall portion 11 of the light guide plate housing member 11 that covers the respective surfaces of the light guide plate 7
b, the light is totally reflected toward the inside of the light guide plate 7 on the mirror-finished inner surfaces of the side walls 11d, 11d and the lower wall 11e.

The light from the light source 5 which enters the inside of the light guide plate 7 from the upper end surface 7c and reaches the surface 7a except for the portion facing the display portion 3d of the dial 3 on the surface 7a Front wall portion 11a of light guide plate housing member 11 covering portion 7a
Is totally reflected toward the inside of the light guide plate 7. On the other hand, the light from the light source 5 which reaches the surface 7a of the surface 7a of the light guide plate 7 which faces the display portion 3d of the dial 3 is emitted outward from the surface 7a of the light guide plate 7, and After passing through the slit 11c formed in the front wall portion 11a of the light guide plate housing member 11 corresponding to the light guide plate housing member 11, the light is emitted to the outside of the light guide plate housing member 11 and transmitted from the back surface of the substrate 3a to the front surface. 3b, passes through the white translucent layer 3b, and further exits through the slits 3e of the black impermeable layer 3c to the front of the dial 3, and the light illuminates the display unit 3d. .

With the vehicle instrument 1A of the second embodiment configured as described above, the same effects as those of the vehicle instrument 1 of the first embodiment can be obtained.

The vehicle instrument 1 according to the first embodiment described above.
Then, the light guide plate 7 excluding the portion facing the display portion 3d of the dial 3
Not only the surface 7a of the light reflecting layer 9 is covered with the surface layer 9a, but also the back surface 7b of the light guide plate 7, both side end surfaces 7d, 7d, and the lower end surface 7e. The light reaching each of the surfaces 7b, 7d, 7e of the light guide plate 7 is covered with the side layer portions 9d, 9d and the lower layer portion 9e, and the mirror surface of the corresponding layer portions 9b, 9d, 9e of the light reflection layer 9 is used. In the processed surface, the light is reflected toward the inside of the light guide plate 7. However, a part of each of the surfaces 7 b, 7 d, and 7 e of the light guide plate 7,
Alternatively, the configuration for reflecting light inside on all surfaces may be omitted.

However, each surface 7b, 7
By providing a configuration for reflecting the light reaching d and 7e toward the inside of the light guide plate 7, the surface layer 9a of the light reflection layer 9 is provided.
In the surfaces 7b, 7d, 7e of the light guide plate 7 other than the top surface 7a covered with the light and the upper end surface 7c on which the light from the light source 5 is incident, the light guided inside the light guide plate 7 is outside the light guide plate 7. And the amount of light in the light guide plate 7, and thus the amount of transmitted illumination of the display unit 3 d of the dial 3, can be more reliably prevented from lowering. It is advantageous.

In the instrument 1A for a vehicle according to the second embodiment, the front surface 7a of the light guide plate 7 except for the portion facing the display portion 3d of the dial 3 and the entire back surface 7b are connected to the light guide plate housing member 11 Not only the front wall portion 11a and the back wall portion 11b, but also the side end surfaces 7d, 7d and the lower end surface 7e of the light guide plate 7
Side walls 11d, 11d and lower wall 1 of light guide plate housing member 11
The light reaching each of the surfaces 7d and 7e of the light guide plate 7 is covered with the corresponding wall portion 11 of the light guide plate housing member 11.
The mirror-finished inner surfaces of d and 11e are configured to reflect toward the inside of the light guide plate 7.
A configuration for reflecting light inside on one of the surfaces d and 7e may be omitted.

That is, even if at most two of the three side walls 11d and the lower wall 11e of the light guide plate housing member 11 are omitted, the remaining one wall portion allows the front wall to be formed. Part 1
1a and the back wall portion 11b, and the light guide plate housing member 1
The integrated structure as 1, 11d can be maintained.
Moreover, if it is considered only for the connection between the front wall portion 11a and the back wall portion 11b, the wall portion connecting these two wall portions 11a and 11b is a corresponding side end surface 7d and a lower end surface 7e of the light guide plate 7. It may be a dimension that covers a part, not the whole.

In the vehicle instruments 1 and 1A of the first and second embodiments described above, the outer surface of the light guide plate 7 extends from the surface 7a of the light guide plate 7 except for the portion where the display 3d of the dial 3 faces. The surface layer 9a of the light reflection layer 9 and the front wall 11a of the light guide plate accommodating member 11 for preventing light from being emitted to the surface 7a of the light guide plate 7
However, a light reflecting member for preventing light from being emitted from the surface 7a of the light guide plate 7 to the outside of the light guide plate 7 is provided on the back surface of the substrate 3a of the dial 3. It is good also as a structure provided.

Further, in the vehicle instruments 1 and 1A of the first and second embodiments described above, the transmissive illumination of the translucent display portion 3d of the dial 3 is provided by a light guide disposed behind the dial 3. Although the description has been given of the case where the light is guided by the light source 5 via the light plate 7, the present invention is not limited to this. For example, the light from the light source is guided by the light guide plate and reflected by the light reflecting surface to form the dial. Needless to say, the present invention can be applied to a vehicular instrument that guides a self-luminous pointer having a light incident surface formed at a position facing the through hole of the dial, which is disposed in front of the dial and passes through the through hole. In this case, the illuminated member in the claims serves as a pointer.

[0041]

As described above, according to the vehicle instrument of the present invention, the light guide plate is provided behind the dial, and the front surface of the light guide plate and the back surface of the dial are provided. And the light is incident from the peripheral end surface of the light guide plate and guided inside the light guide plate, and the light emitted from the surface of the light guide plate and applied to the back surface of the dial is the front surface of the dial. Side, and the light is used to illuminate the illuminated member arranged on the front surface side of the dial, in a vehicle instrument, wherein the back surface of the dial and one of the surfaces of the light guide plate ,
A light that reflects light emitted from the surface of the light guide plate toward the inside of the light guide plate, to the one surface portion except at least a portion corresponding to a surface portion where the illuminated member faces the surface of the dial plate. The configuration was such that a reflection member was provided.

For this reason, of the light reflected from the back surface of the light guide plate, the dial plate is transmitted from the back surface side to the front surface side, guided to the illuminated member, and excluding other light paths other than the optical path of the light necessary for illumination. Since the light path is blocked by a light reflecting member formed on one of the back surface of the dial and the surface of the light guide plate and reflected toward the inside of the light guide plate, it is not used for illuminating the illuminated member. Prevents the light in the optical path from being emitted from the light guide plate and absorbed and attenuated when illuminating the dial, ensuring the amount of light necessary for illuminating the illuminated member, and in the direction along the front and back surfaces of the dial. It is possible to prevent variations in the amount of illumination light due to differences in the position of the illuminated member.

According to the second aspect of the present invention, the light reflecting member is disposed on the front surface of the light guide plate, and the light emitted from the rear surface is provided on the back surface of the light guide plate. Is provided on the back surface of the light guide plate.

Therefore, when the light guided inside the light guide plate reaches the back surface of the light guide plate, the light reflecting member for the back surface formed on the back surface directs the light toward the inside of the light guide plate, that is, the light guide plate. Since the light is reflected toward the front surface of the light plate, light other than the optical path of light that needs to be emitted to the dial side for illumination of the illuminated member is emitted to the outside of the light guide plate on the back surface of the light guide plate. Thus, it is possible to prevent light from leaking, and to more reliably prevent attenuation of light guided in the light guide plate.

Further, according to the vehicle instrument of the present invention described in claim 3, at least a part of the peripheral end surface portion excluding the peripheral end surface portion where the light is incident on the peripheral end surface of the light guide plate, A light reflecting member for the peripheral end face that communicates the light reflecting member and the light reflecting member for the back surface, and reflects light emitted from at least a part of the peripheral end face portion toward the inside of the light guide plate; The light guide member is disposed, and the light reflection member, the back surface light reflection member, and the peripheral end surface light reflection member are integrally formed by a light guide plate housing member in which the light guide plate is housed. In a state where the light guide plate is housed in the member, an opening for exposing at least a portion of the circumferential end surface of the light guide plate where the light is incident to the outside of the light guide plate housing member is inserted into and taken out of the light guide plate. Provided in the light guide plate housing member with a possible size It was constructed.

For this reason, by accommodating the light guide plate inside from the open portion of the light guide plate accommodating member, the front and rear surfaces of the light guide plate and the peripheral end surface portion of the peripheral end surface of the light guide plate excluding the peripheral end surface where light is incident. At least a part of the light reflecting member, the light reflecting member for the back surface, and the light reflecting member for the peripheral end surface are in a state of being provided, respectively. It is possible to easily arrange the light guide plate, and it is possible to prevent light from leaking out of the light guide plate from the peripheral end surface portion of the light guide plate where the light reflection member for the peripheral end surface is arranged,
Attenuation of light guided in the light guide plate can be prevented more reliably.

Further, according to the vehicle instrument of the present invention as set forth in claim 4, the peripheral end face portion of the light guide plate excluding the peripheral end face portion where the light is incident is entirely covered with the light guide plate. The light emitted from the peripheral end face portion is reflected toward the inside of the light guide plate.

Therefore, the light guided inside the light guide plate is
When the light of the light guide plate reaches the peripheral end surface portion excluding the peripheral end surface portion where the light is incident, the light is reflected toward the inside of the light guide plate by the peripheral end surface light reflecting member formed on the peripheral end surface portion,
In the entire peripheral end surface portion except the peripheral end surface portion where the light of the light guide plate is incident, light other than the optical path of the light that needs to be emitted to the dial side for illumination of the illuminated member is outside the light guide plate. Emission and leakage can be prevented, and the reliability of preventing attenuation of light guided in the light guide plate can be further increased.

[Brief description of the drawings]

FIG. 1 is a sectional view of a vehicle instrument according to a first embodiment of the present invention.

FIG. 2 is a front view of the light guide plate shown in FIG.

FIG. 3 is a sectional view of a vehicle instrument according to a second embodiment of the present invention.

FIG. 4 is a perspective view of the light guide plate housing member shown in FIG. 3;

[Explanation of symbols]

3 dial plate 3d display unit (member to be illuminated) 7 light guide plate 7a light guide plate surface 7b light guide plate back surface 7c light guide plate upper end surface (peripheral end where light from the light guide plate is incident) 7d light guide plate side end surface (light from the light guide plate) 7e Light guide plate lower end surface (the peripheral end surface portion excluding the peripheral end surface portion where light of the light guide plate is incident) 9a Light diffusing plate surface layer portion (light reflecting member) 9b 9d Light diffusion plate side layer (peripheral end surface light reflection member) 9e Light diffusion plate lower layer portion (peripheral end surface light reflection member) 11 Light guide plate housing member 11a Light guide plate Housing member front wall portion (light reflecting member) 11b Light guide plate housing member back wall portion (backside light reflecting member) 11d Light guide plate housing member side wall portion (peripheral end surface light reflecting member) 11e Light guide plate housing member lower wall portion (periphery) Light reflection member for end face) 11f Light guide plate housing member insertion port (open) )

Claims (4)

[Claims] 1. A light guide plate is provided behind a dial, a front surface of the light guide plate and a back surface of the dial are opposed to each other, and light is incident from a peripheral end surface of the light guide plate to form a light guide plate. Lead inside,
The light emitted from the front surface of the light guide plate and applied to the back surface of the dial is transmitted to the front surface of the dial, and the light illuminates the illuminated member arranged on the front surface of the dial. In the vehicle instrument, the one of the back surface of the dial and the surface of the light guide plate, except for a portion corresponding to at least a surface portion facing the illuminated member on the surface of the dial, A vehicle instrument, wherein a light reflecting member that reflects light emitted from the surface of the light guide plate toward the inside of the light guide plate is disposed on the surface portion. 2. A light reflecting member for a back surface, wherein the light reflecting member is disposed on a surface of the light guide plate, and a light emitted from the back surface is reflected on a back surface of the light guide plate toward the inside of the light guide plate. The vehicle instrument according to claim 1, further comprising: 3. The light-reflecting member and the back-surface light-reflecting member are connected to at least a part of the peripheral end surface portion of the peripheral end surface of the light guide plate excluding the peripheral end surface portion where the light is incident, And, a light reflecting member for the peripheral end surface that reflects light emitted from at least a part of the peripheral end surface portion toward the inside of the light guide plate is provided, the light reflecting member, the light reflecting member for the back surface, And, in a state where the light reflecting member for the peripheral end surface is integrally formed by a light guide plate housing member in which the light guide plate is housed, and the light guide plate is housed in the light guide plate housing member,
An opening for exposing at least a portion of the peripheral end surface of the light guide plate where the light is incident to the outside of the light guide plate accommodation member is provided in the light guide plate accommodation member in a size that allows the light guide plate to be taken in and out. The vehicle instrument according to claim 2. 4. The light emitted from the peripheral end surface portion is directed toward the inside of the light guide plate over the entire peripheral end surface portion except the peripheral end surface portion where the light is incident on the peripheral end surface of the light guide plate. The vehicle instrument according to claim 2 or 3, further comprising a light reflecting member for a peripheral end surface that reflects light.