JP2003344117A - Illuminating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an illuminating device which suppresses unbalance of illumination colors, and enhances illumination quality. <P>SOLUTION: The illuminating device is provided with a (second) light source 9, a display board 7 which is transmission-illuminated by the light of this light source 9, and a light guide 10 which guides the light of the light source 9 to this display board 7. This device has a reflecting surface 21 which radially reflects the light of the light source 9 which the light guide 10 has guided in, and transmits the light to the display board 7 side. The device is constituted so that the display board 7 is illuminated by the light L1 reflected by this reflecting surface 21 and the light L2 transmitted through it. A diffusing board 24 is provided with a translucent toning layer 27 between this reflecting surface 21 and the display board 7, and suppresses the passage of a longer wavelength component B out of wavelength components of light which has been transmitted through the reflecting surface 21 and proceeds towards the display board 7 side. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an illuminating device for illuminating a display device or an operating device mounted on a vehicle such as an automobile, a motorcycle, a ship, an agricultural construction machine, an aircraft or the like.

[0002]

2. Description of the Related Art Conventionally, there has been known an illuminating device for illuminating a light-transmissive display body by combining a light source and a light guide. For example, in Japanese Unexamined Patent Publication No. 2000-81345, in illuminating a display body composed of a scale plate incorporated in an instrument, a plate-shaped light guide body is arranged between the scale plate and a light source, and the light guide body A technology for providing a reflecting surface having a V-shaped cross section at a position corresponding to a light source, and illuminating a scale plate in a wide range with both the light reflected in the plane direction and the light transmitted in the plate thickness direction through the reflecting surface. It is shown.

Similarly, Japanese Patent Application Laid-Open No. 2-212067 relating to an illumination structure of an instrument.
In Japanese Patent Laid-Open No. 000-292213, a plate-shaped light guide body is arranged behind a plurality of display bodies composed of a pointer and a scale plate, and a reflecting surface inclined at a predetermined angle is provided at a light guide plate portion corresponding to the center of rotation of the pointer. There is disclosed a technique in which a light source is provided and a light source is opposed to the scale, and the scale plate is illuminated with light reflected in the plane direction through the reflecting surface, and the pointer is illuminated with light transmitted through the reflecting surface in the plate thickness direction.

[0004]

By the way, each of the illuminating devices disclosed in the above publications forms a reflecting surface of a light guide body, and the reflected light reflected by this reflecting surface and escapes to the outside through the reflecting surface. Although it is configured to illuminate one or more display bodies with transmitted light, the light guide made of a transparent material has a different refractive index depending on the wavelength of the incident light, and has a short wavelength for short wavelength light. Since light has a low refractive index in the transparent material, long-wavelength light with a low refractive index easily passes through the reflective surface when reflected or transmitted through the reflective surface. There is a problem that the color of the area is different from that of other display bodies or other partial areas, and the color balance of illumination is lost.

For example, when a light emitting diode which emits light of a semiconductor element which emits blue light is converted into white light through a fluorescent filter and emitted, the spectral distribution of the white light is
It can be divided into blue wavelength components and yellow wavelength components, but of the white light that enters the light guide and reaches the reflecting surface,
The yellow wavelength component near the long wavelength is easily transmitted through the reflective surface because the transparent material has a small refractive index, and the blue wavelength component near the short wavelength is easily reflected by the reflective surface because the transparent material has a large refractive index. . As a result, the transmitted light contains more yellow component than the reflected light, and the corresponding display body or display body part is visually recognized as yellowish, and the color balance is disturbed or it feels brighter than other parts. Therefore, there is a problem that the luminance balance is lost.

The present invention has been made in view of this point, and its main object is to provide an illuminating device capable of suppressing an imbalance of illumination colors in a display body.

[0007]

In order to achieve the above object, the present invention provides a light source which emits light of a predetermined color, a single or a plurality of display bodies which are transmitted and illuminated by the light of the light source, and the light source on the display body. And a light guide body for guiding the light of the light source, the light guide body has a reflection surface for reflecting the light of the light source introduced in a predetermined direction and transmitting the light toward the display body side, and the light is reflected through the reflection surface. It is configured to illuminate the display body with light and transmitted light, and between the reflection surface and the display body, of the wavelength components of light that passes through the reflection surface and is directed to the display body side, a long wavelength It is characterized in that a light-transmitting toning filter that suppresses passage of a lean component is provided.

Further, the present invention is characterized in that the display body is a panel body which forms a surface emitting region by the light reflected by the reflecting surface and the light transmitted therethrough.

The present invention is also characterized in that the toning filter is colored in a color having a complementary color relationship with the long wavelength component.

Further, the present invention is characterized in that the emission color of the light source and the illumination color of the display body are white.

The present invention is also characterized in that the toning filter is blue or blue-green.

Further, the present invention is characterized in that the light source comprises a light emitting diode which emits light of a semiconductor device which emits blue light by converting it into white through a fluorescent filter and emitting the white light.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION A case in which an illumination device according to the present invention is applied to a pointer type meter for an automobile will be described below with reference to the accompanying drawings.

FIGS. 1 to 6 show a first embodiment of the present invention, FIG. 1 is a plan view of a pointer type instrument, and FIG. 2 is A- of FIG.
5 is a cross-sectional view taken along line A, FIG. 3 is a cross-sectional view of a main part of a display plate that is a display body, FIG. 4 is a partially enlarged view of an arrow B area in FIG.
Is a spectral diagram showing the emission wavelength distribution of the light source (second light source), and FIG. 6 is a chromaticity diagram for explaining the emission color of the light source and the color of the toning filter.

1 and 2, the pointer-type instrument according to the present embodiment is mounted on a circuit board 1 and a circuit board 1 on the back side of the circuit board 1 in a conductive state, and penetrates the circuit board 1 to the front. A drive device 3 for a speedometer, for example, having a rotating shaft 2 extending in the direction, a pointer 5 having a pointer shaft 4 connected to the tip end side of the rotating shaft 2, and an operation of the pointer 5 arranged behind the pointer 5. A display plate (display body) 7 provided with a display unit 6 corresponding to
The first and second light sources 8 and 9 composed of light emitting diodes mounted on the circuit board 1 around the rotation axis 2 are arranged in front of the second light source 9, and the light is taken inside to the front ( The light emitted from the light guide plate 10 is arranged between the display plate 7 and the circuit board 1 and the light guide body 10 that transmits the light to the display plate 7 side) and reflects the light in the emission direction around the rotation axis 2. And a reflector 12 having a reflecting portion 11 for reflecting the light toward the display plate 7.

The pointer 5 is an indicator portion 13 formed integrally with the pointer shaft 4 and made of a light-transmissive synthetic resin, and a pointer cap 14 made of a light-shielding synthetic resin that covers the periphery of the base of the indicator portion 13.
When the first light source 8 emits light, the light is introduced into the indicator 13 so that the indicator 13 emits linearly. In the case of this example, the emission color of the first light source 8 and the illumination color of the indicator 13 are both red. The pointer 5 is connected to the instrument main body 3 by press-fitting the pointer shaft 4 into the tip end side of the rotating shaft 2 of the instrument main body 3.

A pointer 5 is provided on the display plate 7 in this embodiment.
A display unit 6 such as a scale or a number indicating the speed of the vehicle to be instructed is formed. As shown in FIG. 3, the display board 7 has a ground portion 18 formed by printing a transparent, for example, white ink on the surface of a colorless and transparent substrate 17, and the ground portion 18 is formed.
Further, a display portion 6 is formed by printing with a black ink having a light-shielding property on the surface of the display portion 6, and the display portion 6 is a non-luminous surface emitting panel in which the ground portion 18 is surface emitting. The display unit 6 may be formed of a light-transmitting ink of a color different from that of the base unit 18 so that the entire display unit 6 emits light in a plane.

Further, on the front surface side of the base portion 18, a colorless and transparent protective layer which protects each print layer (the base portion 18 and the display portion 6) and suppresses reflection due to external light when the display plate 7 is visually recognized. 19 is provided.

The circuit board 1 is made of a hard board, and the instrument main body 3 is mounted on the back side in a conductive state, and together with electronic components (not shown) for driving the instrument main body 3, a pointer is provided around the rotary shaft 2. 5 for illuminating 5 and the display board 7 from behind
The light sources 8 and 9 are mounted.

The light guide plate 10 is made of a substantially donut-shaped colorless and transparent synthetic resin having a round hole in the center thereof. This light guide plate 10
Is located between the second light source 9 and the display plate 7 and is a reflector 1
As shown in detail in FIG. 3, the light receiving unit 20 is arranged so as to cover a part of the second light source 2, and the light introduced into the inside from the light receiving unit 20 is forwarded (display panel 7). A reflecting surface 21 that emits (transmits) light to the rear surface) and reflects in the radial direction about the rotation axis 2, and a light emitting portion 22 that emits the light reflected by the reflecting surface 21 in the radial direction. The light transmitted through the reflecting surface 21 and the light reflected by the reflecting surface 21 and emitted through the light emitting portion 22 cause the entire surface of the ground portion 18 of the display plate 7 to emit surface light.

The reflector 12 is made of a white synthetic resin or a white coated product, and reflects the light emitted through the light emitting portion 22 of the light guide 10 toward the display plate 7 side, and the reflected light is mainly used for the display plate 7. In addition to the reflecting portion 11 that illuminates the outer peripheral portion, it has a tubular portion 23 that is erected so as to surround the periphery of the rotating shaft 2. The reflecting portion 11 is formed so as to surround the light guide body 10 in a radial direction, and the tubular portion 23 has a light guide body 1 therein.
A diffuser plate 24 is arranged between the display unit 7 and the display plate 7.

The diffusing plate 24 is composed of a substrate 25 made of, for example, milky white synthetic resin, and a diffusing layer 26 made of a light transmissive white ink printed on the light guide 10 side of the substrate 25.
And a toning layer (toning filter) 2 made of a light-transmitting light blue ink printed on the light guide 10 side of the diffusion layer 26.
Light having a wavelength of 7 and transmitted through the reflecting surface 21 of the light guide 10 toward the display plate 7 side is toned by the toning layer 27 to a color to be described later, and the substrate 25 and the diffusion layer 26 further reflect the light. The central part of the display panel 7 is mainly illuminated by the light that has been toned and diffused.

Here, the second light source 9 is not shown,
A well-known light emitting diode is used which emits light of a semiconductor (light emitting) element after converting it into white through a fluorescent filter mixed with a predetermined fluorescent pigment. In this case, the light emitted by the semiconductor element is blue, and the fluorescence filter passes the blue light emitted by the semiconductor element and at the same time converts part of it into light having a longer wavelength than blue and emits it. The emitted light wavelength distribution is, for example, as shown in FIG. 5, differentiated into a blue short-wavelength component B having a peak near 470 nm and a yellow long-wavelength component Y having a peak near 560 nm. From the observer, each component B,
The white light produced by mixing Y is visible.

When this is expanded into a chromaticity diagram, it is as shown in FIG. 6, and the color coordinates of the light emitted from the second light source 9 are
On the straight line LN connecting the point B (corresponding to the short wavelength component B) and the point Y (corresponding to the long wavelength component Y), the points B and Y
It is located on the white point C near the approximate middle point of.

In this way, the white light emitted from the second light source 9 is introduced into the light guide body 10, reflected (reflected) on the reflection surface 21 and directed to the light emitting portion 22 side, and the reflection surface. The light can be roughly classified into light L2 that passes through 21 and goes out of the light guide body 10. However, a transparent material such as the light guide body 10 has a different refractive index depending on the wavelength component, and light having a short wavelength has a high refractive index of the transparent material. Since light having a long wavelength has a property that the reflectance of the transparent material is small, the second effect is caused by the prism effect through the reflecting surface 21.
Of the wavelength components of the white light emitted from the light source 9, the long-wavelength component Y is more likely to pass through the reflecting surface 21 than the short-wavelength component B, and as a result, the light L2 is slightly smaller than the light L1. It is yellowish and its coordinate point is, for example, point Y in FIG.
Is a point CY (yellowish white) that is located on the straight line LN connecting the point B and the point B and is slightly closer to the point Y than the point C.

The function of differentiating the wavelength component by the reflection / transmission of the reflecting surface 21 is not so large that the respective lights L1 and L2 can be clearly differentiated into two colors of blue and yellow. Is basically the same color as white, but when both are compared, the light L2 is slightly yellowish (affected by the long-wavelength component Y having a low reflectance).
Further, the light L1 contains a larger amount of the component B closer to the short wavelength than the light L2, but the influence of the component B closer to the short wavelength is not so large as being visually recognized as blue light.

Then, the yellowish light L2
Is removed by the toning layer 27 in the process of passing through the diffuser plate 24, so that the light L3 that passes through the diffuser plate 24 and travels toward the display plate 7 becomes diffused light that is white-corrected and is close to the light L1. The entire display panel 7 is illuminated with white and substantially uniform brightness.

That is, the toning layer 27 in this example is a color that is a complementary color of the long wavelength component Y, that is, in FIG.
It is on the straight line LN connecting the points Y and B, and slightly more than the point C.
Since the color is colored with a coordinate point on a point CB (bluish white) that is closer to the point B side, the wavelength component of the light L1 whose coordinate point is on CY while passing through the toning layer 27. Among them, the component Y closer to the long wavelength is absorbed by the complementary color action and then erased, and the light L2 can be corrected to a color closer to the light L1, and as a result, the entire display plate 7 can be illuminated substantially uniformly in white.

As described above, in this embodiment, the second light source 9 and the display plate 7 that is transmitted and illuminated by the light from the light source 9 are provided.
The display plate 7 is provided with a light guide 10 for guiding the light of the second light source 9, and the second light source 9 introduced inside the light guide 10 is provided.
Has a reflecting surface 21 that reflects the light in the radial direction and transmits the light toward the display plate 7 side, and is configured to illuminate the display plate 7 with the light L1 reflected through the reflecting surface 21 and the transmitted light L2. Between the reflective surface 21 and the display plate 7,
A light-transmitting toning layer (toning filter) 27 that suppresses passage of a component B closer to the long wavelength of the wavelength components of light that passes through the reflecting surface 21 and travels toward the display plate 7 is provided on the diffusion plate 24. As a result, when illuminating the display board 7, it is possible to suppress imbalance of illumination colors and improve illumination quality.

In the present embodiment, the display body (display plate 7)
, But the number and shape of the target member or target portion to be illuminated are arbitrary.

Further, particularly in this embodiment, the display body is set to the ground portion 1.
Although the case where 8 is set to the display plate 7 composed of a panel body which emits surface light and the ground portion 18 is made to emit surface light by the light L1 and the light L2 has been shown, in the configuration in which the panel body continuously emits surface light in this way. However, since the color unevenness is easily noticeable, the merit of adopting the present invention is great. It should be noted that the display body is not limited to the display plate 7, and any member can be applied, for example, the pointer 5 or both the pointer 5 and the display plate 7.

Further, in this embodiment, as the toning filter, by adopting the toning layer 27 colored in a color having a complementary color relation to the long-wavelength component Y, excellent color correction can be realized with a simple structure. The toning layer 27 can be formed and the diffusion plate 2
By providing it in No. 4, no special member is required, and the cost is reduced. Although the toning filter is formed by printing in this example, the forming means, the formation target, the shape and the form are arbitrary, and as the forming means, for example, a toning filter is provided by a dedicated colored resin material or a colored film. It may be provided on the back surface of the display plate 7 as an object to be formed, or on the outer wall surface of the light guide 10 corresponding to the reflection surface 21, and the shape or form may be the film thickness. It may be changed, or may be formed in a dot shape having a constant density (density) or a partial density (density) change.

In the present embodiment, the emission color of the second light source 9 and the illumination color of the display plate 9 are set to the same white color.
The present invention is effective in a configuration in which a white light source illuminates the display with white light, because color unevenness is easily noticeable.

In the present embodiment, the case where the second light source 9 is a light emitting diode is shown, but the kind of the light source is arbitrary, and examples of the white light source include an incandescent bulb and a discharge in addition to the light emitting diode. A tube or an electroluminescent element may be adopted. In this case, the color of the toning filter may be adjusted according to the wavelength component that changes depending on the type of light source. For example, when an incandescent bulb is used instead of the light emitting diode, the color of the light L1 that passes through the reflecting surface 21 of the light guide body 10 is reddish white due to the influence of the component near the long wavelength, and thus the color adjustment is performed. As the filter, a filter colored in light blue or light blue-green is suitable.

In the present embodiment, the white light source is used, which is a light emitting diode that emits blue light from a semiconductor element and converts the light into white through a fluorescent filter and emits the white light. In this case, the influence of wavelength differentiation due to the prism effect of the light guide body 10 is likely to be conspicuous, and the adoption of the present invention is effective.

[0036]

As described above, the present invention can provide an illuminating device capable of achieving the initial object, suppressing the imbalance of illumination colors, and improving the illumination quality.

[Brief description of drawings]

FIG. 1 is a plan view of a pointer-type instrument according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a sectional view of a main part of the display plate according to the same embodiment.

FIG. 4 is a partially enlarged view of an arrow B area in FIG.

FIG. 5 is a spectral diagram showing a light emission wavelength distribution of a light source.

FIG. 6 is a chromaticity diagram illustrating a light emission color of a light source and a color of a color matching filter.

[Explanation of symbols]

1 circuit board 2 rotation axis 3 drive 4 pointer axis 5 guidelines 6 Display 7 Display board (display body) 8 First light source 9 Second light source (light source) 10 Light guide 11 Reflector 12 reflector 13 Indicator 14 Pointer cap 17 board 18 ground 19 Protective layer 20 Light receiving part 21 reflective surface 22 Idemitsu 23 Cylindrical part 24 Diffuser 25 substrates 26 Diffusion layer 27 Color matching layer (color matching filter) L1, L2, L3 light

Claims (6)

[Claims] 1. A light guide comprising: a light source that emits light of a predetermined color; a single or a plurality of display bodies that are transmitted and illuminated by the light of the light source; and a light guide body that guides the light of the light source to the display body. The body has a reflection surface that reflects the light of the light source introduced therein in a predetermined direction and transmits the light to the display body side, and illuminates the display body with the light reflected through the reflection surface and the transmitted light. Between the reflection surface and the display body, a light transmissive toning filter that suppresses passage of a long wavelength component of wavelength components of light transmitted through the reflection surface and directed to the display body side. An illuminating device comprising: 2. The illuminating device according to claim 1, wherein the display body is a panel body that forms a surface emission region by the light reflected by the reflection surface and the light transmitted therethrough. 3. The lighting device according to claim 1, wherein the toning filter is colored in a color having a complementary color relationship with the long wavelength component. 4. The illumination device according to claim 3, wherein the light emission color of the light source and the illumination color of the display body are white. 5. The lighting device according to claim 4, wherein the toning filter is blue or blue-green. 6. The illuminating device according to claim 5, wherein the light source is a light emitting diode which converts the light of a semiconductor element emitting blue light into white light through a fluorescent filter and emits the light.