JP2019087506A - Light emitting device - Google Patents

Abstract

To provide a light emitting device which can inhibit occurrence of luminance unevenness of light emission in a transmission part.SOLUTION: A light emitting device includes: a front panel 10 having a transmission part 12; a light guide member 20 which is located at the back side of the front panel 10 and illuminates from front and rear sides of the transmission part 12a; and a light source 40 located at the back side of the light guide member 20. The light guide member 20 has: a light guide part 21 having a light receiving part 21a which receives light from the light source 40 at a position that does not face the transmission part 12a; and an emission part 22 which extends from a side surface 21b of the light guide part 21 in a form that a thickness as seen in an anteroposterior direction is thinner than the light guide part 21 and is formed at a position that faces the transmission part 12a. A curve surface part 23 is formed at a corner part between the light guide part 21 and the emission part 22 at the light source 40 side. The light source 40 is located behind the light receiving part 21a.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a light emitting device mounted on a vehicle or the like, and more particularly to a light emitting device provided with a light guide member for equalizing the luminance of a light source illuminating a design portion.

  As a conventional light emitting device, there is, for example, one disclosed in Patent Document 1. The light emitting device includes a front panel having a transmitting portion, a plurality of light sources disposed on the circuit board, and a light guide disposed in an optical path of illumination light reaching the transmitting portion capable of transmitting the light from each light source. And a case body having a space portion for housing the light sources and the light guide member, wherein the case body has a reflection portion for reflecting the illumination light emitted from the vicinity of the optical axis of the light source toward the transmission portion What is provided is disclosed.

JP, 2016-29427, A

  However, in the light emitting device described in Patent Document 1, light is reflected by the case body made of a white synthetic resin material having a low reflectance, so the reflectance is low and the emission luminance is low. As a countermeasure, if the intensity of the light source is increased, the brightness of the transmission part close to the light source becomes too high, and uneven illumination occurs due to the difference with the transmission part of low emission brightness far from the light source. there were.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a light emitting device capable of suppressing the occurrence of light emission luminance unevenness in the transmission part.

  The present invention includes a front panel 10 having a transmitting portion 12a, a light guide member 20 located behind the front panel 10 and illuminated from the front and rear of the transmitting portion 12a, and a light source located behind the light guide member 20. 40, and the light guiding member 20 includes the light guiding portion 21 having the light receiving portion 21a that receives the light from the light source 40 at a position not facing the light transmitting portion 12a; A light emitting portion 22 extending from the side surface 21 b of the light portion 21 in a shape thinner in the front-rear direction than the light guiding portion 21 and formed at a position facing the transmitting portion 12 a; A curved surface portion 23 is formed at a corner between the light guide portion 21 and the emission portion 22, and the light source 40 is positioned behind the light receiving portion 21a.

  According to the present invention, it is possible to provide a light emitting device capable of achieving the initial object and capable of suppressing the occurrence of uneven emission luminance of the transmission part.

BRIEF DESCRIPTION OF THE DRAWINGS Sectional drawing of the light-emitting device which shows embodiment of this invention. FIG. 2 is a cross-sectional view taken along the line AA of FIG. Sectional drawing along the BB line of FIG. An exploded perspective view of the light guide member and the case member of the present invention The single-piece perspective view of the light guide member of this invention.

  Hereinafter, based on FIGS. 1 to 5, the embodiment will be described by taking the case where the light emitting device M4 of the present invention is applied to, for example, a vehicle instrument mounted on an instrument panel facing the driver's seat of a vehicle. .

  In FIG. 1, a vehicle instrument is provided with a vehicle speed meter M1 and an engine revolution number meter M2 arranged on the left side of the vehicle speed meter M1 and a liquid crystal display panel M3 for displaying various vehicle information between them. A light emitting device M4 is disposed above the liquid crystal display panel M3.

  It should be noted that the vehicle speed meter M1 and the engine speed meter M2 are aligned with the vehicle speed meter M1 as the "right" with "head" as the direction in which the user sitting at the driver's seat from the vehicle meter is viewed as "front". The direction is the left and right direction, the direction of the light emitting device M 4 is “upper”, and the direction in which the liquid crystal display panel M 3 and the light emitting device M 4 are aligned is the vertical direction.

  The light emitting device M4 is formed in a belt shape in which the left and right direction is a longitudinal direction, the vertical direction is a lateral direction, and the longitudinal direction is a gentle arc, and is displayed by emitting light. In the present embodiment, ambient illumination in which blue light emission and green light emission transit according to a predetermined vehicle state is performed.

  The light emitting device M4 includes the front panel 10 having the transmitting portion 12a that forms a band-shaped design so as to transmit light from the light source 40 as described above, a facing member 60 disposed in front of the front panel 10, and a front panel A circuit board 50 disposed behind the front panel 10 in a substantially parallel state with the reference numeral 10, and on the circuit board 50 along the longitudinal direction of the transmission portion 12a to supply illumination light to the transmission portion 12a A plurality of light sources 40 mounted (arranged) at intervals, a light guide member 20 disposed in the light path of illumination light from each light source 40 to the transmission part 12a and illuminating the transmission part 12a from behind, a front panel And a case body 30 having a space 31 for accommodating the light sources 40 and the light guide member 20 and supporting the front panel 10.

  The facing member 60 is made of, for example, a black resin material, and is formed in a cylindrical shape covering the vehicle speed meter M1, the engine rotation speed meter M2, the liquid crystal display panel M3, and the light emitting device M4, and these are exposed for visual recognition. Further, on the front side of the facing member 60, a transparent panel (not shown) made of, for example, a transparent or translucent resin material or the like is disposed. The facing member 60 has a parting portion 61 which overlaps with one side of the transmitting portion 12a and forms a part of the design emitting light in the form of a strip.

  The front panel 10 includes a thin plate-like light transmitting substrate 11 made of light transmitting polycarbonate and the like, a black layer 12 on which a light shielding black ink is print-formed on the back surface of the light transmitting substrate 11, And a smoke layer 13 formed by printing semi-transparent smoke-colored ink on the rear surface of the substrate 11. The transmitting portion 12 a is formed by not printing the black ink of the black layer 12 in a band shape. The smoked layer 13 is formed in a band shape at a position facing the transmission portion 12 a. The front panel 10 is sandwiched and fixed between the facing member 60 and the case body 30.

  The case body 30 is formed of, for example, a white synthetic resin material, is disposed between the front panel 10 and the circuit board 50, and is a space 31 surrounding the outer shape of the light guide member 20 in the vertical and horizontal directions. And a bottom plate portion 32 positioned between the light guide member 20 and the circuit board 50. The bottom plate portion 32 has an opening 32 a at a position facing the light source 40 to allow the light from the light source 40 to pass through the light guiding member 20.

  Further, as shown in FIG. 4, the case body 30 has a positioning hole 33 into which the positioning pin 26 formed in the light guide member 20 is inserted in the space 31, and the positioning pin 26 is inserted into the positioning hole 33 Thus, the light guide member 20 is positioned. Further, the case body 30 supports the front panel 10 on the front surface, and fixes the circuit board 50 on the rear surface.

  The light source 40 is a light source whose emission color can be changed. For example, the light source 40 is a three-color LED packaged with LEDs (chip-type light emitting diodes) of three primary colors RGB. The light beams are arranged at equal intervals along the longitudinal direction of the transmitting portion 12a, and the light is emitted toward the front panel 10 (front-rear direction).

  Further, the position of the light source 40 in the vertical direction is located above the position facing the transmitting portion 12 a. Here, as the light source 40, a light source having a light irradiation area angle of approximately 60 degrees in the vertical and horizontal directions centering on the optical axis is employed. This means that each light source 40 has a light irradiation area angle of approximately 120 degrees.

  The circuit board 50 is formed of a hard wiring board to which a predetermined wiring pattern is applied, and is used to control the rotation of the pointers P1 and P2 included in each of the vehicle speed meter M1 and the engine speed meter M2, display control of the liquid crystal display panel M3, A control means (not shown) comprising a microcomputer for performing light emission control of each light source 40 and various circuit parts (not shown) such as a resistor and a capacitor are electrically connected to the wiring pattern.

  The light guide member 20 is formed in a substantially rectangular parallelepiped shape by a milky white translucent synthetic resin material containing a light diffusion material, and its front view shape is a band shape opposed to the shape of the transmission portion 12a. Further, as shown in FIG. 4, the positioning pin 26 extends from the upper side surface 21 b of the light guide member 20, and the positioning pin 26 is inserted into the positioning hole 33 and positioned in the case body 30.

  In addition, the light guide member 20 is formed at a position not facing the back of the transmitting portion 12a, and the light guiding portion 21 located above the transmitting portion 12a and an emitting portion formed at the position facing the back of the transmitting portion 12a. And 22. The light guide portion 21 and the emission portion 22 are integrally formed. The emission part 22 is formed to be thinner in the front-rear direction than the light guide 21 and is formed to extend from the side 21 b in the front-rear direction on the front panel 10 side of the light guide 21. In addition, the light guide member 20 has a concave R-shaped curved surface portion 23 at the corner between the light guide portion 21 and the emission portion 22 on the light source 40 side. The light guiding unit 21 includes a light receiving unit 21 a that receives the light of the light source 40.

  Further, in the light guide member 20, the position of the side surface 21b having the curved surface portion 23 of the light guide portion 21 substantially coincides with the position of the parting portion 61 in the front view. The surface of the light guide member 20 facing the front panel 10 has a light splitting portion 24 formed in a substantially V-shaped groove and reflecting light in the left-right direction at a position approximately directly above the light source 40. Further, the surface facing the circuit board 50 and the bottom plate portion 32 of the light guide member 20 has a reflecting portion 25 which is formed in a substantially V-shaped groove and reflects light upward at a position between the light sources 40.

  As shown in FIG. 2, of the illumination light emitted from the light source 40, the first illumination light L1 having a relatively high light intensity on the substantially optical axis is incident on the light guide member 20 from the light receiving unit 21a, and the light separating unit The light is reflected to the left and right at 24 and is reflected toward the front panel 10 by the reflector 25 to illuminate the back of the front panel 10. Further, the second illumination light L2 having a relatively low light intensity, which is emitted to a region deviated from the optical axis, enters the light guide member 20 from the light receiving unit 21a, and directly illuminates the back of the front panel 10. Further, as shown in FIG. 3, the first illumination light L1 similarly enters the light guide member 20 from the light receiving portion 21a in the vertical direction, and is reflected in the horizontal direction by the light splitting portion 24. The second illumination light L2 enters the light guide member 20 from the light receiving unit 21a and directly illuminates the transmitting unit 12a of the front panel 10.

  Thus, the transmission part 12a in the vicinity of the light source 40 is mainly illuminated by the second illumination light L2 having a low light intensity, and between the light sources 40, the second illumination light L2 having a low light intensity and the dispersive part 24 The light intensity is attenuated by the light reflected by the reflection portion 25 and illuminated by the first illumination light L1 which is weakened, so the illumination balance is well maintained, and the occurrence of the light emission luminance unevenness of the transmission portion 12a is suppressed can do.

  Further, the position of the side surface 21 b of the light guide member 20 substantially coincides with the position of the parting portion 61. By being formed in this manner, it is possible to prevent the first illumination light L1 having a relatively high light intensity passing through the light guiding portion 21 from being directly irradiated to the transmitting portion 12a, and the light emission luminance of the transmitting portion 12a It is possible to suppress the occurrence of unevenness.

  A concave R-shaped curved surface portion 23 is provided at the corner between the light guide portion 21 and the emission portion 22. Since light is diffused by the curved surface portion 23 when passing from the light guiding portion 21 to the emitting portion 22 by being formed in this manner, the boundary of light can be blurred, and the light emission luminance unevenness of the transmitting portion 12 a Can be suppressed.

  Further, since the light guide member 20 contains a light diffusion material, the light guided in the inside of the light guide member 20 is diffused as needed, so that it is possible to suppress the occurrence of the light emission luminance unevenness.

  In addition, the light guide member 20 may be deformed due to post-shrinkage after injection molding, and when the gap between the light guide member 20 and the space 31 is narrow, the light guide 20 does not interfere with the space 31 and does not enter There is a case.

  However, since the light guide member 20 of the present embodiment has the V groove shape alternately formed on the surface on the front panel 10 side and the surface on the circuit board 50 side, flexibility in the front, rear, left, right, up and down directions is provided. Have. As shown in FIG. 5, since flexibility is provided in the vertical and horizontal directions, even if the shape of the light guide member 20 after injection molding does not match the shape of the space portion 31, the light It can be deformed easily and fitted.

  The present invention relates to a light emitting device for a vehicle, and can be applied to, for example, a light emitting device for a vehicle mounted on a mobile body equipped with a car, a motorcycle, or an agricultural machine or a construction machine.

DESCRIPTION OF SYMBOLS 10 front panel 12a transmission part 20 light guide member 21 light guide part 21a light receiving part 21b side 22 emission part 23 curved surface part 40 light source

Claims (4)

A front panel having a transparent portion,
A light guide member located behind the front panel and illuminating the transmission section from behind;
A light source located behind the light guide member;
The light guiding member has a light receiving portion having a light receiving portion that receives light from the light source at a position not facing the light transmitting portion, and a thickness in the front-rear direction from the side surface of the light guiding portion is thinner than the light guiding portion And an emitting portion extending in a shape and formed at a position facing the transmitting portion;
A curved surface portion is formed at a corner between the light guide portion and the emission portion on the light source side,
The light source is located behind the light receiving unit. A facing member disposed in front of the front panel;
The light emitting device according to claim 1, wherein the facing member has a parting portion overlapping the transmitting portion and substantially coinciding with a side surface of the light guiding portion having the curved surface portion. The light source has a plurality of
The light guide member has a light separating portion that reflects light in the left and right direction at a position immediately above the light source on the front panel side in a direction (left and right direction) substantially orthogonal to the front and rear direction and the vertical direction; And a reflective portion configured to reflect light upward at a position between the plurality of light sources,
The light emitting device according to any one of claims 1 to 2, further comprising: a case body that encloses the outer shape of the light guide member behind the front panel.   The light emitting device according to any one of claims 1 to 3, wherein the light guide member is made of a material containing a light diffusion material.

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