JP6148464B2 - Illumination device - Google Patents

Description

  The present invention relates to an illumination device that illuminates a light guide held by a base member with light from a light source.

  In various devices such as an in-vehicle display and a disk player, an illumination device is widely used in which a predetermined operation member or a specific part is illuminated with light from a light source so that the illuminated part functions as an indicator or the like. This type of illumination device includes a base member having a through-hole, a light guide held by the base member so as to close the through-hole, and a light source disposed behind the light guide. The light emitted from the light passes through the light guide that overlaps the through hole and is radiated to the outside.

  In the illumination device having such a configuration, the light source composed of the LED or the like is mounted on the wiring board, but due to restrictions on the component layout of the wiring board and peripheral members, a sufficient distance from the light source to the light guide is secured. In some cases, the light source cannot be placed directly behind the light guide. In that case, luminance unevenness occurs on the illumination surface of the light guide due to the difference in the distance from the light source. Therefore, by changing the thickness of the light guide according to the distance from the light source, A technique for improving luminance unevenness on the illumination surface of the body has been proposed (see, for example, Patent Document 1).

Japanese Utility Model Publication No. 6-28950

  However, in the prior art disclosed in Patent Document 1, luminance unevenness is improved by adjusting the thickness of the light guide made of a resin molded product. Therefore, every time the overall shape of the light guide changes. A new mold must be manufactured, and depending on the overall shape of the light guide, it is necessary to adopt a complicated mold structure, which increases the manufacturing cost of the entire illumination device. It was.

  The present invention has been made in view of the actual situation of the prior art, and an object thereof is to provide an illumination device that can suppress luminance unevenness of a light guide with an inexpensive configuration.

To achieve the above object, the present invention provides a base member having a through hole, a light guide disposed on the front side of the base member so as to close the through hole, and a back of the light guide. In an illuminating device in which light emitted from the light source is irradiated to the outside through the light guide body that overlaps the through hole, an installation portion formed around the through hole is provided. An elongated optical sheet is disposed so as to cross the through-hole, and the optical sheet is configured to block a part of the through-hole and not the other part, and to fix both ends in the longitudinal direction of the optical sheet. The light guide is pressed against the installation portion.

In the illumination device configured as described above, a part of the light traveling from the light source to the light guide is dimmed (light-shielded or diffused) by the optical sheet, and thus the brightness of the light guide due to the difference in distance from the light source Unevenness can be suppressed. In addition, since both ends in the longitudinal direction of the optical sheet are compressed by the light guide to the installation portion of the base member, backlash of the optical sheet with respect to the installation portion is prevented, and the repulsive force of the optical sheet prevents the light guide from Backlash can also be prevented.

  In the above configuration, a wide portion is formed at least at one end in the longitudinal direction of the optical sheet, and when the wide portion is hooked in a groove formed in the installation portion of the base member, the optical sheet is attached to the installation portion. This is preferable because it can be easily and reliably arranged at a predetermined position.

  Further, in the above configuration, the light guide body is mounted on the installation portion, the illumination portion protruding forward from the flat plate portion and overlapping the through hole, and protruding backward from the flat plate portion and locked to the base member. It is preferable that the light guide is easily and surely attached to the base member.

In the illumination device of the present invention, an optical sheet having a dimming function is disposed in the optical path of light from the light source toward the light guide , and both ends in the longitudinal direction of the optical sheet are placed on the base member by the light guide. Since it is press-contacted to the part, the luminance unevenness of the light guide due to the difference in distance from the light source can be suppressed, and the optical sheet and the light guide can be attached without shakiness.

It is a front view of the vehicle-mounted display apparatus to which the illumination device which concerns on the example of an embodiment was applied. It is a disassembled perspective view which shows the principal part of this display apparatus. FIG. 2 is a detailed view of part A in FIG. 1. It is sectional drawing which follows the IV-IV line of FIG. It is sectional drawing which follows the VV line of FIG. It is a perspective view of the light guide with which an illuminating device is equipped. It is explanatory drawing which shows the assembly procedure of an illuminating device.

  The embodiment of the invention will be described with reference to the drawings. As shown in FIGS. 1 and 2, an in-vehicle display device 1 is attached to a panel body 2 having a rectangular opening 2 a and a back surface of the panel body 2. A base member 3, a light guide 4 held on the front surface of the base member 3, a wiring board 5 attached to the panel main body 2 so as to cover the back surface of the base member 3, and the like. A plurality of operation buttons 6 are disposed on both sides of the front surface of the front panel with the opening 2a interposed therebetween.

  A liquid crystal display (not shown) is disposed on the back side of the panel body 2, and the display surface of the liquid crystal display is exposed in the opening 2a. In addition, a disc player (not shown) is disposed behind the panel body 2, and a disc insertion slot 2b for inserting / ejecting a disc into / from the disc player is formed in the upper front portion of the panel body 2. Yes. The disc insertion opening 2b extends in a slit shape along the upper side of the opening 2a, and an illumination portion 4b of a light guide 4 described later is exposed from both left and right ends of the disc insertion opening 2b.

  The base member 3 is a horizontally long molded product made of a light-shielding resin. As shown in FIGS. 3 to 7, the base member 3 includes a long hole 3 a that overlaps the disk insertion opening 2 b of the panel body 2, and a long shape. A pair of through holes 3b located on the left and right sides of the hole 3a are opened. The periphery of the through-hole 3b is a flat installation portion 3c, and three installation holes 3d are formed in the installation portion 3c. In addition, groove portions 3e are formed on the installation portion 3c so as to sandwich the through hole 3b, and a wide portion 7a of the optical sheet 7 to be described later is hooked on the groove portions 3e. Further, a pair of cylindrical portions 3f that open at the rear ends are formed at both left and right end portions of the base member 3, and through holes 3b and mounting holes 3d are formed on the wall surface on the front end side of these cylindrical portions 3f. ing.

  The light guide 4 is a molded product made of a transparent resin, and the light guide 4 is colored translucent gray called smoke. As shown in FIG. 6, the light guide 4 includes a flat plate portion 4a, an illumination portion 4b that protrudes forward from the flat plate portion 4a, a guide pin 4c that protrudes backward from the flat plate portion 4a, and a rear surface from the flat plate portion 4a. And a pair of hook pieces 4d projecting to the right. The flat plate portion 4a is mounted on the installation portion 3c of the base member 3 via the optical sheet 7, and the illumination portion 4b protrudes forward from a position overlapping the through hole 3b and is inserted into the end portion of the disc insertion port 2b. . The guide pin 4c and the hook piece 4d are inserted into the corresponding mounting holes 3d of the base member 3, and the hook piece 4d is snapped to the inner wall of the cylindrical portion 3f, whereby the light guide 4 is It is held by the installation part 3 c of the base member 3.

  The optical sheet 7 is an elongated sheet body made of a flexible resin film such as PET (polyethylene terephthalate), and wide portions 7 a are formed at both ends in the longitudinal direction of the optical sheet 7. The optical sheet 7 has a dimming function for blocking or diffusing a part of transmitted light. In the case of this embodiment, the black optical sheet 7 having a light blocking function is used. You may use the optical sheet 7 with the spreading | diffusion function to which the process etc. were given. The optical sheet 7 is interposed between the flat plate portion 4a of the light guide 4 and the installation portion 3c. The assembly procedure will be briefly described. First, FIG. 7A and FIG. As shown in b), the wide portion 7 a of the optical sheet 7 is hooked on the groove portion 3 e of the base member 3. Accordingly, the optical sheet 7 is positioned with respect to the installation portion 3c, and the optical sheet 7 is mounted on the installation portion 3c so as to straddle the through hole 3b. In this state, when the guide pin 4c and the hook piece 4d are inserted into the corresponding mounting holes 3d of the base member 3 and the hook piece 4d is snap-coupled to the inner wall of the cylindrical portion 3f, as shown in FIG. The light guide 4 is attached to the installation part 3 c of the base member 3. As a result, the optical sheet 7 is sandwiched between the flat plate portion 4 a and the installation portion 3 c in a state where the optical sheet 7 is pressed against the installation portion 3 c of the base member 3 by the flat plate portion 4 a of the light guide 4. The backlash of the optical sheet 7 with respect to the installation part 3 c is prevented, and the backlash of the light guide 4 is prevented by the repulsive force of the optical sheet 7.

  A pair of LEDs 8 that are light sources are mounted on the wiring board 5, and these LEDs 8 are located in the rear end opening of the corresponding cylindrical portion 3 f of the base member 3. The light emitted from the LED 8 passes through the internal space of the cylindrical portion 3 f and reaches the illumination portion 4 b of the light guide 4 that overlaps the through hole 3 b, and then passes through the illumination portion 4 b to the front of the panel body 2. Emitted. At that time, since the optical sheet 7 is disposed so as to straddle the through-hole 3b, a part of the light traveling from the LED 8 toward the illumination unit 4b is dimmed (shielded or diffused) by the optical sheet 7, and the distance from the LED 8 is reduced. The uneven brightness of the light guide 4 due to the difference can be suppressed.

  As described above, the illumination device according to the present embodiment includes the base member 3 provided with the through hole 3b, and the light guide 4 arranged on the front side of the base member 3 so as to close the through hole 3b. The LED 8 is mounted on the wiring board 5 behind the light guide 4 and the optical sheet 7 is disposed in the installation portion 3c so as to cross the through hole 3b. A part of the light traveling toward the body 4 can be dimmed (shielded or diffused) by the optical sheet 7. Therefore, even when the distance from the LED 8 to the light guide 4 cannot be sufficiently secured or the LED 8 cannot be disposed directly behind the light guide 4, the luminance unevenness of the light guide 4 can be suppressed only by adding the optical sheet 7. The manufacturing cost including the mold cost of the light guide 4 can be reduced. In addition, when the light guide 4 is attached to the base member 3, the optical sheet 7 is pressed against the installation portion 3c of the base member 3 by the light guide 4, so that the optical sheet 7 is prevented from rattling with respect to the installation portion 3c. At the same time, rattling of the light guide 4 is prevented by the repulsive force of the optical sheet 7, and the optical sheet 7 can be provided with two functions of a light control function and a backlash prevention function.

  In the present embodiment, the wide portion 7a is formed at the longitudinal end portion of the optical sheet 7, and the wide portion 7a is hooked on the groove portion 3e formed in the installation portion 3c of the base member 3. The optical sheet 7 can be easily and surely arranged at a predetermined position of the installation portion 3c at the time of assembling, and the optical sheet 7 can be prevented from being displaced due to external vibration after installation.

  In this embodiment, the light guide 4 includes a flat plate portion 4a mounted on the installation portion 3c, an illumination portion 4b protruding forward from the flat plate portion 4a and overlapping the through hole 3b, and a rear side from the flat plate portion 4a. Therefore, the light guide 4 can be easily and reliably attached to a predetermined position of the base member 3 because the hook piece 4d that protrudes toward the base member 3 and is integrally molded with the hook piece 4d.

  In the above embodiment, the illumination device of the present invention is used as an indicator of the disc insertion slot 2b of the disc player. However, it can be used as an operation display unit of other devices, or It can also be used as an illumination part of a movable member such as an operation button.

DESCRIPTION OF SYMBOLS 1 In-vehicle display apparatus 2 Panel main body 2b Disk insertion port 3 Base member 3b Through-hole 3c Installation part 3d Mounting hole 3e Groove part 3f Cylindrical part 4 Light guide 4a Flat plate part 4b Illumination part 4c Guide pin 4d Hook piece 5 Wiring board 7 Optical sheet 7a Wide part 8 LED (light source)

Claims (3)

A base member having a through hole, a light guide disposed on the front side of the base member so as to close the through hole, and a light source provided behind the light guide, and emitted from the light source. In the illuminating device in which the emitted light passes through the light guide that overlaps the through hole and is irradiated to the outside,
An elongated optical sheet is disposed across the through hole in an installation portion formed around the through hole, and a part of the through hole is blocked by the optical sheet so that the other part is not blocked. In addition, an illumination device, wherein both ends of the optical sheet in the longitudinal direction are pressed against the installation portion by the light guide.   2. The illumination device according to claim 1, wherein a wide portion is formed at least at one end portion in the longitudinal direction of the optical sheet, and the wide portion is hooked to a groove portion formed in the installation portion. .   3. The light guide according to claim 1, wherein the light guide body includes a flat plate portion mounted on the installation portion, an illumination portion that protrudes forward from the flat plate portion and overlaps the through hole, and protrudes rearward from the flat plate portion. And a hook piece locked to the base member.