JP4514569B2 - Display device - Google Patents

Description

  The present invention relates to a display device, and more particularly to a display device that displays a travel distance, a remaining fuel amount, and the like in a vehicle meter such as an automobile.

  As an example of a conventional display device, a light source is provided in a light source storage portion outside the window portion of the instrument panel, and the case is opposed to the display panel with an air layer therebetween and reflects light from the light source toward the display panel. A display device provided with a unit is known (see, for example, Patent Document 1).

  As shown in FIGS. 6 and 7, the display device 100 disclosed in Patent Document 1 has a light source 102 mounted on a substrate 110 provided outside the window 107 of the instrument panel 106, and a liquid crystal display panel in the case 108. Reference numeral 103 denotes a reflector 101 that is opposed to the air layer 109 and reflects light from the light source 102 toward the liquid crystal display panel 103.

  The reflector 101 is formed as an inclined surface that gradually approaches the liquid crystal display panel 103 as the distance from the light source 102 increases, and is formed so as to reflect the light from the light source 102 toward the liquid crystal display panel 103.

In such a display device 100, by providing the light source 102 outside the window 107 of the instrument panel 106, it is not necessary to place the light source 102 directly below the liquid crystal display panel 103. The distance in the height direction (vertical direction in FIG. 6) can be reduced, and the display device 100 can be made thinner.
JP 2001-12596 A (page 3-4, FIG. 2, FIG. 4)

  In the display device 100 disclosed in Patent Document 1, in order to reduce illumination unevenness of the liquid crystal display panel 103, the light source 102 and the liquid crystal are continuously connected to the upper edge of the opening of the light source housing 104 from the upper edge. A light-shielding plate 105 is provided that extends obliquely between the display panel 103 and blocks light emitted from the light source 102 to the display panel 103, and a black silk is provided in a light-emitting side peripheral region of the light source 102. A dark-colored light absorbing portion 111 formed by printing is provided. This prevents the area near the light source 102 of the liquid crystal display panel 103 from becoming too bright.

  However, as shown in FIG. 7, the light shielding plate 105 is provided from one end to the other end of the upper edge of the opening of the terminal accommodating portion 104, and both side edges of the opening of the terminal accommodating portion 104 are closed. . For this reason, it becomes more difficult to irradiate the both side edges of the display panel 103 where the irradiation light is difficult to reach with the irradiation light of the light source 102, which may cause uneven illumination of the liquid crystal display panel 103.

  In addition, no measures are taken with respect to the light emitted from the light source 102 blocked by the shielding plate 105, and it is not effectively used because it is absorbed by the inner wall of the terminal accommodating portion 104 or the light absorbing portion 111. In order to improve the utilization efficiency of the irradiation light emitted from the light source 102, further measures have been desired. In addition, illumination unevenness occurred in the portion where the display panel 103 was directly irradiated from the light source 102.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to improve the utilization efficiency of the irradiation light from the light source and to eliminate the uneven illumination of the display panel due to the direct light from the light source. It is to provide a display device with high performance.

  In order to achieve the above object, a display device according to the present invention is characterized by the following (1) and (2).

(1) a display panel;
A light source that emits irradiation light that illuminates the display panel from the back side;
A light guide that guides the irradiation light emitted from the light source to the display panel;
A display device comprising:
The light source is disposed outside the display panel on the back side of the display panel;
The light guide is
A reflection part for reflecting the irradiation light emitted from the light source toward the back surface of the display panel;
A light source accommodation chamber that has an opening on the reflection portion side, is tapered so as to gradually expand toward the opening, and has all inner wall surfaces as reflection surfaces;
A light shielding plate that shields the irradiation light directly irradiated from the light source to the back surface of the display panel and reflects the light toward the inner wall surface of the light source storage chamber,
The light shielding plate is formed in the opening of the light source accommodation chamber, extending from the upper edge of the opening near the display panel, with a gap between the side edge and the lower edge. Being.

(2) In the display device described in (1) above,
The light source accommodation chamber has a stepped portion and is formed in a taper shape in two steps, and the light source is arranged on the stepped portion.

  According to the configuration described in (1) above, the light directly emitted from the light source to the back surface of the display panel is blocked by the light shielding plate, and the display panel is illuminated only by indirect light. . Thereby, uneven illumination of the display panel can be eliminated. In addition, since there is a gap (light exit) between the light shielding plate and both side edges of the opening, the irradiation light emitted from the light source is also applied to both side edges of the display panel where the irradiation light is difficult to reach. It can be made easy to reach. Thereby, uneven illumination of the display panel can be eliminated. Furthermore, since the light source housing chamber is formed in a tapered shape that expands toward the opening, the emitted light that is blocked by the light shielding plate and reflected toward the light source housing chamber is reflected in the light source housing chamber that is a reflective surface. Reflected by the wall surface, it goes to the opening without fail. Thereby, the irradiation light emitted from the light source can be used efficiently, and the brightness of the display panel can be improved.

  According to the configuration described in (2) above, the step portion is provided and the light source accommodation chamber is formed in a tapered shape in two steps, and a space for arranging the light source can be secured by this step portion, and therefore the taper is formed. The light source accommodation chamber (and thus the entire display device) can be thinned while maintaining the shape.

  According to the display device of the present invention, it is possible to improve the utilization efficiency of the irradiation light from the light source, eliminate the uneven illumination of the display panel due to the direct light from the light source, and provide a display device with high visibility. .

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the drawings.
1 is an exploded perspective view of a meter device incorporating an embodiment of a display device according to the present invention, FIG. 2 is a sectional view of the display device shown in FIG. 1, and FIG. 3 is a light guide portion of the display device shown in FIG. FIG. 4 is a partially broken perspective view around the light guide light source housing chamber of the display device shown in FIG. 1, and FIG. 5 is a sectional view of a modification of the display device shown in FIG.

  As shown in FIG. 1, a display device 10 according to an embodiment of the present invention emits a liquid crystal panel (LCD) 11 as a display panel and irradiation light for illuminating the back surface of the liquid crystal panel 11. For example, a light source 12 such as a light emitting diode (LED), a light guide 13 that guides the emitted light from the light source 12 to the back surface of the liquid crystal panel 11, and a driver (for driving the liquid crystal panel 11) (Not shown), and the travel distance, the remaining amount of fuel, and the like are displayed on the liquid crystal panel 11. The meter device 50 in which the display device 10 is incorporated includes a front glass 51, a turning plate 52, a dial plate 53 in which a pointer 54 is disposed at the center, a light conductor 55, a case 56, and an electric circuit board 58. And a back cover 63.

  The front glass 51 is made of a transparent synthetic resin and is assembled to the facing 52 so as to cover the front surface of the facing 52.

  The facing 52 is made of, for example, a synthetic resin, is formed in a cylindrical shape, and is assembled to the back cover 63 so as to cover the periphery of the display portion of the dial plate 53.

  The dial 53 is a panel made of polycarbonate, for example, and has a disk shape in which a speed display design portion 64 and various warning display design portions 65 and 66 including a direction indication design portion are arranged. In addition, a pointer hole 67 through which the pointer rod of the pointer 54 passes is provided in the central portion of the various warning display design portions 65, and a window 68 for the liquid crystal panel 11 of the display device 10 is provided in the side portion. It has been.

  The light conductor 55 is interposed between the dial 53 and the case 56, and is interposed between the case 56 and the back cover 63 behind the case 56 through an optical path hole 70 of the case 56 described later. The irradiation light emitted from the speedometer LED 69 attached to the electric circuit board 58 to be collected is condensed, and the speed display design portion 64 of the dial 53 is illuminated from the back side.

  The case 56 is formed in a substantially disc shape made of a white or milky white synthetic resin, and has a plurality of optical path holes 70 for guiding the irradiation light from the speedometer LED 69 of the electric circuit board 58 to the light conductor 55, and an electric circuit. A plurality of optical path holes 73 and 74 for guiding light from the plurality of warning display LEDs 71 and 72 attached to the substrate 58 to the various warning display design portions 65 and 66 of the dial plate 53 and a pointer rod of the pointer 54 are penetrated. And a reset knob 57 for operating a reset switch 76 disposed on the electric circuit board 58 is assembled therethrough. The tip of the reset knob 57 passes through the light conductor 55, dial 53, dial 52, and front glass 51, and can be operated from the outside. A display panel attachment portion 77 to which the liquid crystal panel 11 of the display device 10 is attached is provided on a side portion of the case 56 (that is, a position corresponding to the window 68 of the dial 53).

  The electric circuit board 58 is, for example, a printed wiring board having a hard insulating board and a circuit pattern of a conductor on the hard board, and is assembled behind the case 56. On the surface of the electric circuit board 58, a speedometer LED 69 at a position corresponding to the optical path hole 70 of the case 56, warning display LEDs 71 and 72 at positions corresponding to the optical path holes 73 and 74 of the case 56, and the case 56 A reset switch 76 is attached at a position corresponding to the reset knob 57 assembled to the. On the back surface of the electric circuit board 58, a flasher relay 59, an electric movement 60 for driving the pointer 54 by being coupled with a pointer rod of the pointer 54, and a wire harness for transmitting electric power and various signals (all not shown). And the like are connected to the connectors 61 and 62.

  Then, the side surface of the electric circuit board 58 (position corresponding to the terminal portion of the liquid crystal panel 11 attached to the display panel attachment portion 77 of the case 56) is electrically connected to the plurality of terminal portions of the liquid crystal panel 11. For example, a connection portion 78 such as a multipolar connector is provided, and the light source 12 of the display device 10 is attached in the vicinity of the connection portion 78. The electric circuit board 58 is provided with the driver for driving the liquid crystal panel 11 of the display device 10. In the present embodiment, the driver of the display device 10 is integrated and integrated with an electronic control IC (that is, a so-called ECU) that controls the entire meter device 50. Accordingly, the electronic control IC drives the liquid crystal panel 11 of the display device 10 based on various signals input via the connectors 61 and 62.

  The back cover 63 is made of, for example, a synthetic resin and has a bottomed cylindrical shape. The back cover 63 is assembled with a dial 52 that accommodates the meter substrate 58, the case 56, the light conductor 55, and the dial 53.

Further, the display device 10 will be described in detail with reference to FIGS.
The liquid crystal panel 11 of the display device 10 is attached to the display panel attachment portion 77 of the case 56. Further, a terminal accommodating portion 79 that communicates with the connection portion 78 of the electric circuit board 58 is provided adjacent to the display panel mounting portion 77, and the terminal portion of the liquid crystal panel 11 is accommodated in the terminal accommodating portion 79 so as to be an electric circuit. It is electrically connected to the connection part 78 of the substrate 58.

  The light source 12 is attached to the surface of the meter substrate 58 so as to be disposed outside the liquid crystal panel 11 on the back side of the liquid crystal panel 11 attached to the display panel attachment portion 77 of the case 56. It is electrically connected to the circuit pattern. The light source 12 emits irradiation light that illuminates the liquid crystal panel 11 from the back side when supplied with current.

The light guide unit 13 includes a reflection unit 14, a light source accommodation chamber 15, and a shielding plate 16.
The reflecting portion 14 is a plate-like member formed integrally with the case 56 and is disposed behind the liquid crystal panel 11. The reflecting portion 14 is formed to be inclined so as to gradually approach the liquid crystal panel 11 as the distance from the light source 12 increases. Therefore, the surface of the reflecting portion 14 irradiates the light emitted from the light source 12 with the liquid crystal panel 11. Reflect on the back. The reflecting portion 14 is made of the same white or milky white synthetic resin as the case 56, whereby the surface is a reflecting surface, and this surface uniformly applies the light emitted from the light source 12 to the back surface of the liquid crystal panel 11. It is made into an appropriate curved surface so that it can be reflected. In addition, the said surface of the reflection part 14 may be made into a reflective surface by the mirror surface process by plating or metal vapor deposition.

  The light source accommodation chamber 15 is defined by a hood portion 18 that covers the light source 12 attached to the surface of the electric circuit board 58 from above and a part of the electric circuit board 58 and accommodates the light source 12. An opening 17 is provided on the side. The hood portion 18 includes a ceiling wall 18 a disposed above the light source 12, a rear wall 18 b disposed behind the light source 12 (on the side opposite to the opening 17), and side walls disposed on both sides of the light source 12. 18c, 18c, the ceiling wall 18a is formed to be inclined so as to gradually approach the electric circuit board 58 as the distance from the opening 17 increases, and the side walls 18c, 18c are formed in the opening 17. The light source accommodation chamber 15 is formed in a tapered shape so as to gradually expand toward the opening 17 as a whole. Yes.

  The hood portion 18 is formed integrally with the case 56, and is therefore made of the same white or milky white synthetic resin as the case 56, whereby the ceiling wall 18a, the rear wall 18b, and the side walls 18c, 18c. Each of the inner wall surfaces is a reflecting surface. In addition, the inner wall surface of the ceiling wall 18a, the rear wall 18b, and the side walls 18c and 18c may be made into a reflective surface by mirror finishing by plating or metal deposition. In addition, a part of the electric circuit board 58 that defines the light guide unit 13 is formed as a reflection surface 20 by applying a white or milky white paint or attaching a non-conductive reflection seal. .

  The light shielding plate 16 is suspended from the edge of the ceiling wall 18 a that forms the upper edge of the opening 17 near the liquid crystal panel 11 in the opening 17 of the light source accommodation chamber 15, and is connected to the reflecting surface 20 of the electric circuit board 58. A gap 24 is placed between the gaps (that is, between the lower edges of the opening 17) and a gap 25 is placed between the side walls 18c and 18c (that is, between the side edges of the opening 17). Irradiation light other than the direct light is formed between the light source 12 and the irradiation light (hereinafter referred to as direct light) directly irradiated from the light source 12 to the back surface of the liquid crystal panel 11 and between the periphery of the opening 17. A substantially U-shaped injection port for injecting the light into the reflecting portion 14 is defined. The light shielding plate 16 has at least a surface 26 of the light shielding plate 16 facing inward of the light source accommodation chamber 15 as a reflective surface similar to the ceiling wall 18 a of the hood portion 18. Therefore, the direct light blocked by the light shielding plate 16 is reflected toward the light source accommodation chamber 15 by the surface 26 of the light shielding plate 16.

  As described above, the light source accommodation chamber 15 is formed in a tapered shape that expands toward the opening 17, and the inner wall surface of the light source accommodation chamber 15 (that is, the ceiling wall 18 a and the rear wall 18 b of the hood portion 18). Since both the inner wall surfaces of the side walls 18c and 18c and the reflection surface 20) of the electric circuit board 58 are reflection surfaces, the light reflected from the surface 26 of the light shielding plate 16 toward the light source storage chamber 15 is reflected on the inner surface. The direct light is reflected by the inner wall surface of the light source accommodation chamber 15 and is reliably directed to the opening 17 and is emitted from the emission port. Then, the irradiation light emitted from the emission port is reflected toward the back surface of the liquid crystal panel 11 by the reflection unit 14.

  In particular, the outlet is defined by the shielding plate 16, the side walls 18 c and 18 c of the light source accommodation chamber 15, and the electric circuit board 58, and a gap 25 placed between the shielding plate 16 and the side walls 18 c and 18 c. Irradiated light emitted from the light is incident on both side edges of the reflecting portion 14 and reflected toward both side edges of the liquid crystal panel 11. Thereby, the back surface of the liquid crystal panel 11 is illuminated uniformly.

  Then, the liquid crystal panel 11 is driven by the driver of the display device 10 so that a predetermined region is in a transmissive state and other regions are in a non-transmissive state, whereby the display device 10 is in a transmissive state of the liquid crystal panel 11. Information such as travel distance and fuel remaining amount is displayed by the irradiation light transmitted through the designated area.

  According to the display device 10 described above, the direct light directly irradiated on the back surface of the liquid crystal panel 11 out of the irradiated light emitted from the light source 12 is blocked by the light shielding plate 16, and the liquid crystal panel 11 is illuminated only by indirect light. It is. Thereby, the illumination unevenness of the liquid crystal panel 11 is eliminated. Since a gap 25 (light emission port) is also provided between the light shielding plate 16 and both side edges of the opening 17, the light source is also emitted from both sides of the liquid crystal panel 11 where the irradiated light is difficult to reach. It is possible to make the irradiated light easily reach. Thereby, the illumination unevenness of the liquid crystal panel 11 is eliminated. Furthermore, since the light source accommodation chamber 15 is formed in a tapered shape that expands toward the opening portion 17, the emitted light that is blocked by the light shielding plate 16 and reflected into the light source accommodation chamber 15 is used as a reflection surface. It is reflected by the inner wall surface of the light source accommodation chamber 15 and is surely directed toward the opening 17. Thereby, the utilization efficiency of the irradiation light emitted from the light source 12 is improved, and the brightness of the liquid crystal panel 11 is improved. Therefore, the visibility of the liquid crystal panel 11 is improved.

  Next, a modification of the display device 10 will be described with reference to FIG. In addition, description is abbreviate | omitted by attaching | subjecting the same code | symbol to the member which is common in the display apparatus 10 mentioned above.

  As shown in FIG. 5, in this modification, a step portion 27 is provided in the middle portion of the ceiling wall 18a of the hood portion 18 that defines the terminal accommodating chamber 15, and the terminal accommodating chamber 15 is formed in a taper shape in two steps. Is. The light source 12 is provided on the electric circuit board 58 so as to be located immediately below the stepped portion 27.

  In this modification, a space for arranging the light source can be secured by the stepped portion 27, and thus the light source accommodation chamber 15, and thus the display device 10 as a whole, can be thinned while maintaining a tapered shape.

  In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably. For example, the meter device is not limited to a speedometer, and may be a combination meter with a speedometer and a tachometer. In that case, a display device may be arranged on the side of the tachometer, or the center of both meters may be A display device may be arranged in the part.

It is a disassembled perspective view of the meter apparatus incorporating one Embodiment of the display apparatus which concerns on this invention. It is sectional drawing of the display apparatus shown in FIG. It is an external appearance perspective view of the light guide part of the display apparatus shown in FIG. FIG. 2 is a partially cutaway perspective view around a light guide light source accommodation chamber of the display device shown in FIG. 1. It is sectional drawing of the modification of the display apparatus shown in FIG. It is sectional drawing of the conventional display apparatus. It is a partially broken front view of the conventional display device shown in FIG.

Explanation of symbols

10 Display Device 11 Liquid Crystal Panel (Display Panel)
12 Light Source 13 Light Guide 14 Reflector 15 Light Source Chamber 16 Light Shield 17 Opening 27 Step

Claims (2)

A display panel;
A light source that emits irradiation light that illuminates the display panel from the back side;
A light guide that guides the irradiation light emitted from the light source to the display panel;
A display device comprising:
The light source is disposed outside the display panel on the back side of the display panel;
The light guide is
A reflection part for reflecting the irradiation light emitted from the light source toward the back surface of the display panel;
A light source accommodation chamber that has an opening on the reflection portion side, is formed in a tapered shape so as to gradually expand toward the opening and has an inner wall surface as a reflection surface, and accommodates the light source;
A light-shielding plate that blocks the irradiation light directly irradiated from the light source to the back surface of the display panel and reflects the light toward the inner wall surface of the light source storage chamber;
Have
The light shielding plate is formed in the opening of the light source accommodation chamber, extending from the upper edge of the opening near the display panel, with a gap between the side edge and the lower edge. A display device.   The display device according to claim 1, wherein the light source accommodation chamber has a stepped portion and is formed in a tapered shape in two steps, and the light source is disposed on the stepped portion.

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