JPH0764486A - Light emitting display device - Google Patents

Abstract

PURPOSE:To prevent lowering of contrast of an indicator lens due to the influence of extraneous light. CONSTITUTION:An indicator lens 9 made of acryl resin is provided with a plane of incidence 9a receiving incident light from a LED 8, and a fit part 9c having a display plane 9d, and lightly force-fitted and fixed to a slider 7 a, under the condition in which the fit part 9c is fitted in a display window 5a provided on a knob 5. In the indicator lens 9, the form of the lens side 9e is decided so that the angle of incidence of an extraneous light to the lens side 9e is larger than a total reflection angle, when the incident extraneous light to the indicator lens 9 through the display plane 9b is directed to the lens side 9e of the lens 9. All the reflection light totally reflected at the lens side 9e is directed to the plane of incidence 9a, and relation between the plane of incidence 9a and the lens side 9e is set so that the incident angle of the reflection light (extraneous light) against the plane of incidence 9a is smaller than the total reflection angle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting display device,
In particular, it is suitable as an indicator device used in an electric device such as an audio device and an air conditioner mounted on a vehicle.

[0002]

2. Description of the Related Art Conventionally, there is an indicator device used for an electric device such as an audio device mounted on a vehicle or an air conditioner. As shown in FIG. 23, this indicator device includes a light emitting element 100 (for example, an LED) and an indicator lens 110 arranged to face the light emitting element 100.
And a slider 120 for holding the indicator lens 110, a knob 130 for shielding the periphery of the display surface 111 of the indicator lens 110, and the like. The light emitted from the light emitting element 100 is the indicator lens 1
The light enters from the incident surface 112 of 10 and is emitted to the outside from the display surface 111 of the indicator lens 110.

[0003]

However, in the conventional indicator device, at night when the vehicle interior is dark, the light emitting element 100 is ON (when it is emitting light) and OFF.
The contrast of the indicator lens 110 is clear when the light emitting element 100 is ON and when the light emitting element 100 is ON.
Since the contrast of the indicator lens 110 is lowered when F is applied, it is difficult to identify the control state of the device by the display of the indicator lens 110.

This is an indicator lens 11 from the outside.
The extraneous light that has entered 0 is reflected by the inside of the indicator lens 110 or a peripheral component (for example, the slider 120) of the indicator lens 110, and again the indicator lens 110
This is because the light is transmitted through and emitted to the light emitting element 100 as if the indicator lens 110 were turned on even when the light emitting element 100 was turned off. This is because, even when 100 is turned on, reflected light exceeding the amount of light is emitted.
The present invention has been made in view of the above circumstances, and an object thereof is to provide a light emitting display device capable of preventing a decrease in contrast of an indicator lens due to the influence of external light.

[0005]

In order to achieve the above-mentioned object, the present invention provides a shield member provided with a display window, the periphery of which is shielded, and a shield member disposed inside the shield member. A light emitting means for performing a light emitting action, an incident surface disposed between the shielding member and the light emitting means, on which light of the light emitting means is incident, and a display surface appearing in the display window, In a light emitting display device comprising an indicator lens for emitting the light of the light emitting means incident on the display surface from the display surface, and a peripheral component arranged around the light emitting means and the indicator lens, the indicator lens is the shield. When external light that has passed through the display surface from the outside of the member and enters the inside of the shielding member is directed to the lens side surface from the incident surface to the display surface, the external light with respect to the lens side surface Angle of incidence with the shape of the lens side is determined to be larger than the total reflection angle,
When the reflected light totally reflected on the lens side surface goes to the incident surface, the shape of the incident surface is determined so that the incident angle of the reflected light with respect to the incident surface is smaller than the total reflection angle,
The technical means is that at least a portion of the peripheral component facing the incident surface is covered with a color that absorbs light.

[0006]

In the light emitting display device of the present invention having the above structure, when external light (for example, sunlight) enters from the outside of the shield member through the display surface of the indicator lens to the inside of the shield member, the external light When going to the lens side surface from the incident surface to the display surface, extraneous light is totally reflected by the lens side surface. When the reflected light totally reflected by the side surface of the lens goes to the incident surface of the indicator lens, most of the reflected light passes through the incident surface and goes out of the indicator lens without being totally reflected by the incident surface. . The light (external light) that has passed through the incident surface is absorbed by the peripheral component whose portion facing the incident surface is covered with a color that absorbs light. As a result, even if external light enters the indicator lens, the amount of external light that goes out of the indicator lens again decreases.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a first embodiment of the light emitting display device of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view of an indicator device (light emitting display device). As shown in FIG. 4, the indicator device 1 of the present embodiment has an air conditioner operation panel 3 installed on an instrument panel 2 in a vehicle compartment.
Applied to. The indicator device 1 includes a knob 5 (shielding member of the present invention) arranged on the front case 4 and manually operated by an occupant, an internal switch 6 for electrically converting the operation of the knob 5, and an internal switch 6 for operating the knob 5. Slider 7 (peripheral component of the present invention), internal switch 6
LED 8 (light emitting element of the present invention) which emits light when is turned on, indicator lens 9 arranged between knob 5 and LED 8, and the like.

The knob 5 is a molded product of a light-transmissive milky white acrylic resin and has a design portion (not shown) formed by laser cutting after the surface of the molded article is painted black.
Further, the knob 5 is provided with a display window 5a (see FIG. 3) for illuminating and displaying the ON state of the device through the indicator lens 9. The knob 5 is lightly press-fitted into the end of the slider 7, and the slider 7 is engaged by the claw fitting.
It is fixed to. The front case 4 is made of ABS.
It is a resin molded product and its surface is painted black.

The slider 7 is a molded product of white ABS resin, and a plurality of rails 7a provided around the slider 7 are fitted in the grooves 4a provided in the front case 4 to form a front case 4
It is assembled so that it can slide with respect to. The internal switch 6 is a self-reset type switch including a rubber boot 6a for return, and operates only while an operating force is applied, and returns to the state before the operation by removing the operating force. Therefore, when an occupant pushes the knob 5 and an operating force is applied, the return rubber boot 6a is deformed and an internal contact (not shown) is short-circuited. When the occupant releases his finger from the knob 5, the operating force is returned. The internal contact is separated by the elastic force of the rubber boot 6a and returns to the original position.

The LED 8 is a directional self-luminous device having a constant viewing angle, and is held by a holder 10 (peripheral component of the present invention) and soldered to a circuit board 11. The holder 10 is a molded product of ABS resin, and the surface after molding is painted black and assembled to the circuit board 11. The circuit board 11 (glass epoxy board) is the front case 4
It is fixed by a screw (not shown). Also,
The circuit board 11 has a bulb 1 for illuminating the design portion of the knob 5.
2 is assembled. The light from the bulb 12 is emitted by the slider 7
The light is diffused and guided by the reflection surface of the, and the back side of the knob 5 is illuminated.

The indicator lens 9 is a molded product of transparent acrylic resin, and the entire surface is mirror-finished.
As shown in (a top view of the indicator lens) and FIG. 3 (a front view of the indicator lens), an incident surface 9a on which light of the LED 8 is incident, a fitting portion 9c having a display surface 9b,
And a locking portion 9d for positioning is formed, and the fitting portion 9d
In the state where c is fitted in the display window 5a of the knob 5, it is lightly press-fitted and fixed to the slider 7. The acrylic resin has a visible light transmittance of 93% and a surface reflection of normally incident light of 7%, and hardly absorbs visible light. The refractive index n of the acrylic resin is 1.49.

In order to efficiently direct the light of the LED 8 to the occupant's EyePoint direction, the indicator lens 9 has a distance between the indicator lens 9 and the LED 8, a shape of the incident surface 9a, and a display surface 9b of the fitting portion 9c. The shape is set as follows. Now, as shown in FIG. 5, the light of the LED 8 having the viewing angle α ° is changed to the width β of the display surface 9b (see FIG.
Assuming that the indicator lens 9 of (see) is irradiated, the distance L from the light source of the LED 8 to the incident surface 9a of the indicator lens 9 is set to a value obtained by the following formula.

## EQU1 ## L ≧ 1 / tan (α / 2) × β / 2

LED illuminated on the indicator lens 9
The light of 8 is refracted once on the incident surface 9 a of the indicator lens 9, then passes through the fitting portion 9 c and goes out of the indicator lens 9 through the display surface 9 b. Therefore, the incident surface 9a is on the outside (LED) so that all the light refracted on the incident surface 9a becomes parallel rays (see FIGS. 5 and 6) toward the display surface 9b.
It has a convex shape that swells gently toward the (8 side).

When the light of the LED 8 goes out of the indicator lens 9 from the display surface 9b, it is refracted again on the display surface 9b. Therefore, it is necessary to deflect the light refracted on the display surface 9b so as to be directed in the EyePoint direction of the occupant. Therefore, in the present embodiment, the display surface 9b is cut so that both the driver seat side and the passenger seat side have directivity (see FIG. 5).

In addition, the indicator lens 9 of this embodiment
When the external light that has entered the indicator lens 9 from the display surface 9b is directed to the lens side surface 9e from the incident surface 9a to the fitting portion 9c, the incident angle of the external light on the lens side surface 9e is the total reflection angle. The shape of the lens side surface 9e is determined so as to be larger than (critical angle: 42 ° 10 '). Further, the relation between the incident surface 9a and the lens side surface 9e is such that all the reflected light totally reflected by the lens side surface 9e is directed to the incident surface 9a and the incident angle of the reflected light on the incident surface 9a is smaller than the total reflection angle. Is set.

Next, the operation of this embodiment will be described. When the occupant pushes the knob 5 (ON operation), the internal switch 6 is turned on via the slider 7, so that the internal switch 6 outputs an ON signal. By the ON signal of the internal switch 6, a current flows through the LED 8 to emit light. The valve 12 is a vehicle light switch (not shown)
Lights in conjunction with.

The light emitted from the LED 8 is incident on the incident surface 9a of the indicator lens 9 at a constant viewing angle α °. Here, the light of the LED 8 is refracted and becomes substantially parallel rays when passing through the incident surface 9a (see FIGS. 5 and 6).
The parallel rays are refracted again when passing through the display surface 9b of the fitting portion 9c, and are projected in the EyePoint direction of the occupant (driver side and passenger side). In this way, the light from the LED 8 passes through the indicator lens 9 and the E of the occupant efficiently.
Since it is directed toward the yePoint, the occupant uses the LED8
The light emitting state of can be recognized.

Next, the influence of external light incident on the display surface 9b of the indicator lens 9 will be described. It should be noted that external light enters the display surface 9b from all directions, and therefore an example will be described. First, as shown in FIGS. 7 and 8, the incident angles θ (angles with respect to the normal to the lens side surface 9e) to the lens side surface 9e are the external lights a, b, and c that are refracted on the display surface 9b and travel toward the lens side surface 9e. Is larger than the total reflection angle, the light is totally reflected by the lens side surface 9e toward the incident surface 9a (see FIG. 9 and enlarged view of portion A in FIG. 7). The external light traveling to the incident surface 9a has an incident angle with respect to the incident surface 9a (angle with respect to the normal to the incident surface 9a) smaller than the total reflection angle, and therefore most of the external light passes through the incident surface 9a (refraction). Then go out of the indicator lens 9. Part of the extraneous light reflected by the incident surface 9a goes to the lens side surface 9e or the display surface 9b.

Here, the relationship between the incident angle and the surface reflectance when the light enters the indicator lens 9 and the relationship between the incident angle and the internal reflectance when the light exits the indicator lens 9 are shown in FIG. And shown in FIG.
In the figure, the case where the vibration direction of the incident light is in the plane defined by the incident direction and the normal is indicated by R1, and the vibration direction of the incident light is vertical to the plane defined by the incident direction and the normal. The case is R
Shown by 2.

As shown in FIG. 12, the reflectance when light is emitted from the indicator lens 9 is such that the incident angle is the total reflection angle (4
In the case of 2 ° 10 ') or less, it becomes approximately 5% or less. Therefore, the external light totally reflected by the lens side surface 9e is incident on the incident surface 9a.
Is smaller than the total reflection angle, the incident surface 9a
The external light reflected by the incident surface 9 is about 5% or less of the whole, and most of the external light does not reflect on the incident surface 9a and is incident on the incident surface 9a.
It passes through a and goes out of the indicator lens 9. The extraneous light that has passed through the incident surface 9a and goes out of the indicator lens 9 goes toward the holder 10 side that holds the LED 8. Since the holder 10 is coated with a black color that absorbs light, extraneous light emitted outside the indicator lens 9 is
It will be absorbed by the holder 10.

Next, after refracting at the display surface 9b, the fitting portion 9
The extraneous light D directed to the side surface 9f of the c is the side surface 9 of the fitting portion 9c.
Since the incident angle γ with respect to f (the angle with respect to the normal to the side surface 9f) is smaller than the total reflection angle, most of the external light passes through the side surface 9f of the fitting portion 9c and a part of the external light ( About 5% or less of the whole) is reflected by the side surface 9f of the fitting portion 9c (see FIG. 10 and enlarged view of portion B in FIG. 7). And the fitting portion 9
External light that has passed through the side surface 9f of c hits the wall surface of the fitting hole of the knob 5 into which the fitting portion 9c is fitted, but is absorbed by the knob 5 because the surface of the knob 5 is painted black. Become.

Subsequently, a state in which extraneous light enters the indicator lens 9 from the display surface 9b was observed by simulation. The results are shown in FIGS.
According to this simulation, after entering the inside of the indicator lens 9 from the display surface 9b, about 72.9% of the extraneous light emitted from the incident surface 9a to the outside of the indicator lens 9 (see FIG. 13), the side surface of the fitting portion 9c. About 6% of the extraneous light goes out of the indicator lens 9 from 9f (see FIG. 14), about 1.44% of the extraneous light goes out of the indicator lens 9 from the side surface 9e of the lens (see FIG. 15), and again the display surface 9b. The external light emitted from the indicator lens 9 was about 1.4% (see FIG. 16).

As described above, most of the extraneous light entering the indicator lens 9 from the display surface 9b (about 7
2.9%) was confirmed to go out of the indicator lens 9 through the incident surface 9a. Most of the extraneous light emitted to the outside of the indicator lens 9 from the incident surface 9a and the side surface 9f of the fitting portion 9c is absorbed by the holder 10 and the knob 5, so that the external light exits the indicator lens 9 from the display surface 9b again. It never comes out.

From the lens side surface 9e to the indicator lens 9
The external light that has exited outside is diffusely reflected by the white slider 7 and enters the inside of the indicator lens 9 again, and what percentage (less than 1%) of it is outside the indicator lens 9 from the display surface 9b again. It is possible to go to. Therefore, the extraneous light emitted from the display surface 9b to the outside of the indicator lens 9 is
It is estimated to be less than 2% at best.

On the other hand, in the case of the conventional indicator lens 110 shown in FIG. 23, as a result of carrying out the same simulation, the indicator lens 110 is seen from the incident surface 112.
About 58% of the external light goes out of the room (see Fig. 17), knob 13
External light emitted from the side surface 113 of the indicator lens 110 fitted to 0 to the outside of the indicator lens 110 is about 5.
9% (see FIG. 18) and about 12.8% of extraneous light emitted from the lens side surface 114 to the outside of the indicator lens 110 (see FIG. 1).
9), and again from the display surface 111, the indicator lens 1
The amount of extraneous light coming out of 10 was about 3.5% (see FIG. 20).

Comparing the results of this simulation, in the case of this embodiment, the amount of extraneous light emitted from the display surface 9b to the outside of the indicator lens 9 is reduced to less than half that in the conventional case, and the indicator lens 9 from the lens side surface 9e. The external light emitted to the outside is reduced to about 1/9 of that in the conventional case (therefore, the external light emitted from the lens side surface 9e and then reflected by the slider 7 again to the display surface 9b is reduced. To). As a result, in this embodiment, the extraneous light that has entered the indicator lens 9 from the display surface 9b again exits the indicator lens 9 from the display surface 9b and the passenger's Ey
The proportion toward the ePoint direction is very small. As a result, when the LED8 is off (when it is not emitting light)
In addition, the indicator lens 9 does not seem to be lit up by the influence of external light, and even when the LED 8 is ON (when it is emitting light), the reflected light does not exceed the amount of light, so that the LED 8 The contrast of the indicator lens 9 becomes clear depending on whether it is ON or OFF.

FIG. 21 shows a second embodiment of the present invention. As shown in FIG. 21, the indicator lens 9 of the present embodiment is
The lead-out portion 13 is provided on the lens side surface 9e. The lead-out portion 13 is provided so that the external light E entering the lead-out portion 13 through the display surface 9b is totally reflected by the side surface of the lead-out portion 13 and goes out of the indicator lens 9 from the lead-out portion 13. Therefore, it is desirable that the peripheral parts arranged at the portion facing the end face of the lead-out portion 13 be coated with a color (for example, black) capable of absorbing the external light emitted from the lead-out portion 13. In addition, all the external light that enters the lens side surface 9e other than the lead-out portion 13 is totally reflected by the lens side surface 9e, travels toward the incident surface 9a, and goes out of the indicator lens 9 through the incident surface 9a.

FIG. 22 shows a third embodiment of the present invention. As shown in FIG. 22, the indicator lens 9 of the present embodiment is
Since the elongated lead-out portions 13 are provided on both sides of the lens side surface 9e, the same effect as that of the second embodiment can be expected.

[0029]

According to the light emitting display device of the present invention, after the external light entering the inside of the indicator lens from the display surface is totally reflected by the side surface of the lens, most of the external light exits from the incident surface to outside the indicator lens. Since the light is absorbed by the parts, the amount of extraneous light that goes out of the indicator lens from the display surface again decreases. As a result, when the light emitting means is not emitting light, the indicator lens never seems to be illuminated due to the influence of extraneous light, and the indicator light is emitted when the light emitting means is emitting light and when it is not emitting light. The contrast of the lens becomes clear, and the visibility can be improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an indicator device according to this embodiment.

FIG. 2 is a top view of an indicator lens.

FIG. 3 is a front view of an indicator lens.

FIG. 4 is a perspective view showing an instrument panel in a vehicle compartment.

FIG. 5 is a diagram showing a light ray of an LED transmitted through an indicator lens.

FIG. 6 is a diagram showing a light ray of an LED transmitted through an indicator lens.

FIG. 7 is a diagram showing a state when external light is incident on the indicator lens.

FIG. 8 is a diagram showing a state when external light is incident on the indicator lens.

9 is an enlarged view of part A in FIG.

10 is an enlarged view of part B in FIG. 7. FIG.

FIG. 11 is a graph showing the relationship between the incident angle on the indicator lens and the surface reflectance.

FIG. 12 is a graph showing the relationship between the incident angle of the indicator lens and the internal reflectance.

FIG. 13 is a diagram showing a simulation result of external light.

FIG. 14 is a diagram showing a simulation result of extraneous light.

FIG. 15 is a diagram showing a simulation result of extraneous light.

FIG. 16 is a diagram showing a simulation result of extraneous light.

FIG. 17 is a diagram showing a simulation result of external light (conventional example).

FIG. 18 is a diagram showing a simulation result of external light (conventional example).

FIG. 19 is a diagram showing a simulation result of external light (conventional example).

FIG. 20 is a diagram showing a simulation result of external light (conventional example).

FIG. 21 is a front view of an indicator lens according to a second example.

FIG. 22 is a front view of an indicator lens according to Example 3.

FIG. 23 is a schematic configuration diagram of a conventional indicator device.

[Explanation of symbols]

 1 Indicator Device (Light Emitting Display Device) 5 Knob (Shielding Member) 5a Display Window 7 Slider (Peripheral Parts) 8 LED (Light Emitting Means) 9 Indicator Lens 9a Incident Surface 9b Display Surface 9e Lens Side Surface 10 Holder (Peripheral Parts)

Claims (1)

[Claims] 1. A shield member provided with a display window and shielding the periphery of the display window, a light emitting means disposed inside the shield member for performing a light emitting action, the shield member and the light emitting means. And an indicator which is disposed between the light emitting means and has an incident surface on which the light of the light emitting means is incident, and a display surface which appears on the display window, and which emits the light of the light emitting means incident on the incident surface from the display surface. In a light emitting display device comprising a lens and peripheral parts arranged around the light emitting means and the indicator lens, the indicator lens passes from the outside of the shielding member through the display surface to the inside of the shielding member. When the external light entering the lens is directed to the lens side surface from the incident surface to the display surface, the incident angle of the external light on the lens side surface is larger than the total reflection angle. The shape of the side surface is determined, and when the reflected light totally reflected by the lens side surface goes to the incident surface, the shape of the incident surface is such that the incident angle of the reflected light with respect to the incident surface is smaller than the total reflection angle. In the light emitting display device, at least a portion of the peripheral component facing the incident surface is covered with a color that absorbs light.