JP2000039857A - Surface light source illumination display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enlarge a uniform visual sense angle in which a design display part is bright and the brightness looks uniform in a surface light source illumination display device. SOLUTION: This surface light source illumination display device is comprised of a display body 11 and a surface light source 13 illuminating the display body 11 from behind, and the display body 11 is provided with a magnifying glass 18a for magnifying the uniform visual sense angle β between a body 12 and the surface light source 13 in the surface light source illumination display device which forms a design display layer 15 consisting of a translucent design part 16 and a shading background part 17 on the front face of the body 12. The light of the surface light source 13 is transmitted through the translucent design part 16 while being converged and focused in the neighborhood of the trans design part 16, and then, reaches the eye position 20 of an observer while being diverged. Therefore, the uniform visual sense angle β in which the translucent design part 16 looks uniformly bright is enlarged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface light source illumination display device provided with nighttime illumination, and more particularly to a surface light source illumination display device for illuminating a design portion with a surface light source from behind.

[0002]

2. Description of the Related Art Conventionally, this type of surface light source illumination display device has been used, for example, as a switch operation knob mounted on a dashboard of an automobile. As shown in FIG. 1, the surface light source illumination display device includes a transparent body 1 having a design display portion 2 having a design portion 3 made of characters, designs, and the like and a design display portion 2 having a background portion 4 formed on a front surface thereof, , And illuminates the design display unit 2 from behind at night use. The design portion 3 and the background portion 4 are formed by applying a high-reflectance paint and a low-reflectance paint on the front surface of the transparent body 1 in a solid shape with a predetermined thickness, respectively. In addition, an EL surface light source is used as the surface light source 5 in order to reduce the size and thickness of the body. For example, an organic dispersion type EL in which an EL emitter is dispersed and bonded with an organic binder is usually used.

In the above-mentioned surface light source illumination display device, when light hits the design display portion 2 in the daytime, the design portion 3 having a high reflectance exhibits a bright color and the background portion 4 having a low reflectance exhibits a dark color. These color differences are recognized as contrast. At night, the surface light source 5 provided in the transparent body 1 is caused to emit light, and the design portion 3 is placed from behind the transparent body 1.
When the design portion 3 and the background portion 4 are illuminated, the difference in brightness between the design portion 3 illuminated by the transmitted light and the shaded background portion 4 is visually recognized as the contrast between the design portion 3 and the background portion 4.

[0004] However, as shown in the figure, a viewer who looks at the design display unit 2 from a distance sees that the brightness of the design unit 3 is not uniform due to the visual position 10.

Light emitted from the lower end of the surface light source 5 travels along a lower end line 9a connecting the lower end of the surface light source 5 and the lower end of the design portion 3. A line parallel to the lower end line 9a and passing through the upper end of the design portion 3 is an upper limit line at which the design portion 3 is viewed as having uniform brightness, and is referred to as a uniform visual upper end line 9b.
The light emitted from the upper end of the surface light source 5 travels along an upper end line 9c connecting the upper end of the surface light source 5 and the upper end of the design portion 3. A line parallel to the upper end line 9c and passing through the lower end of the design portion 3 is a lower limit line at which the design portion 3 is viewed as having uniform brightness, and is referred to as a uniform visual lower end line 9d.

For example, when the viewer is at the visual position 10 within a range surrounded by the lower end line 9a and the uniform visual upper limit line 9b, the design portion 3 is made to have uniform brightness in order to see only the surface light source 5. Looks like. On the other hand, when the viewer is above the intersection 10 a between the uniform visual upper limit line 9 b and the visual position 10, the surface light source 5
Also, a part (for example, the switch element 7) below the lower end line 9a, which is deviated from the lower end line 9a, is seen, so that the design part 3 appears to have uneven brightness.

Similarly, when the viewer is at the visual position 10 within a range surrounded by the upper end line 9c and the uniform visual lower limit line 9d, the design portion 3 looks uniform brightness, and the uniform visual lower limit line 9d.
When d is below the intersection 10b between the visual position 10 and
The design part 3 looks uneven brightness.

That is, in the conventional surface light source illumination and display device, the viewer views the uniform visual upper limit line 9 b and the uniform visual lower limit line 9.
The design part 3 looks uniform brightness only when it is within the uniform visual angle (α) formed by d. However, when the design part 3 is out of the angle, the design part 3 has uneven brightness. Looks like. Therefore, the uniform viewing angle (α) at which the design portion 3 looks uniform brightness is small.

As shown in FIG. 2, when the diffusion plate 8 is disposed between the body 1 and the surface light source 5, the light from the surface light source 5 is scattered, and the uniform visual angle (α) is increased. However, since the light transmission loss when the light passes through the diffusion plate 8 is large, the design portion 3 looks dark as a whole.

[0010]

SUMMARY OF THE INVENTION Accordingly, the technical problem to be solved by the present invention is to provide a surface light source illuminating display device in which the design display section is bright and the brightness is uniform, and the uniform viewing angle is large. is there.

[0011]

In order to solve the above-mentioned technical problems, the present invention provides the following surface light source illumination display device.

That is, the surface light source illumination display device of the present invention comprises a display body and a surface light source for illuminating the display body from behind, and the display body is provided with a translucent light on the front surface of the body. In a surface light source illumination display device having a design display layer composed of a design portion and a light-shielding background portion, a magnifying lens for increasing a uniform visual angle is provided between the body and the surface light source.

According to the above configuration, the light from the surface light source is emitted from the surface light source in a planar shape by the magnifying lens, and the light transmitted through the translucent design portion is diverged (that is, the translucent design portion). Light reaches the viewer's visual position (while exiting at a larger angle than without the magnifying lens). Therefore, the translucent design portion looks bright, and the uniform viewing angle at which the brightness looks uniform is large.

A single lens can be used as the magnifying lens.

In the above configuration, a convex lens can be used as a single lens. When the convex lens is arranged so that the focus position is near the front of the translucent design portion, the light of the surface light source passes through the translucent design portion while converging,
Focuses near the front of the translucent design part, and then diverges to reach the viewer's visual position. In addition, when the convex lens is arranged so that the focus position is near the rear of the translucent design portion, the light of the surface light source converges in front of the translucent design portion to form a focus, and then diverges. The light passes through the translucent design portion to reach the viewer's visual position. Therefore, in any case, the uniform viewing angle is enlarged by the convex single lens. In the above configuration, when a concave lens is used as the single lens, the light of the surface light source passes through the translucent design portion while diverging without being focused, and reaches the visual position of the viewer. Therefore, the concave lens enlarges the light of the surface light source similarly to the convex lens, so that the uniform visual angle is enlarged. Therefore, when the magnifying lens is a convex or concave single lens, the translucent design portion looks bright, and the uniform visual angle at which the brightness appears uniform becomes large.

As a magnifying lens, a micro lens array can be used.

According to the above configuration, the light from the surface light source is condensed or diverged by the respective minute lenses according to the convex or concave lens shape, similarly to the single lens. The light from the microlens passes through the translucent design portion and then reaches the visual position of the viewer while diverging. Since the light of the surface light source is emitted from each microlens, the translucent design portion looks more uniform in brightness than when a single lens is used.

In the present specification, the term “single lens” is used to refer to a lens having a diameter parallel to a light exit surface in order to compare with a microlens having a large number of microlenses arranged on a surface parallel to the light exit surface. Is used to mean a lens in which one large lens is arranged. Therefore, a single lens also includes a lens in which a plurality of lenses having a large aperture are combined in a direction orthogonal to the light emission surface.

[0019]

Embodiments of the present invention will be described below in detail with reference to FIGS. A switch operation knob attached to a dashboard of an automobile will be described as an example of the surface light source illumination display device according to the present invention.

FIG. 3 is a sectional view showing a surface light source illumination display device according to one embodiment of the present invention, and FIG. 4 is a sectional view showing a modification of the magnifying lens of FIG. In the figure, a switch operation knob for an automobile as a surface light source illumination display device includes a display body 11, a surface light source 13, a plate-like base 19, and a lens 1.
8a.

The display body 11 has a design display layer 15 formed on the front surface of a dome-shaped transparent resin body 12. The design display layer 15 includes a light-transmitting design portion 16 and a light-shielding background portion 17 which are formed in layers. The translucent design section 16 is provided so that the design display layer 15 can be viewed in the daytime.
Is light (for example, white) and the light-shielding background portion 17 is dark (for example, black). In addition, when the design display layer 15 is illuminated from behind the design display layer 15 by the light (for example, white) of the surface light source 13 at night, a white translucent design portion 16 representing characters and patterns and a black light-shielding background portion 17 are provided. Is visually recognized. As a result, a high contrast is obtained between the translucent design portion 16 and the light-shielding background portion 17. The light-transmitting design portion 16 can be made dark and light-shielding, and the light-shielding background portion 17 can be light-colored and light-transmitting.

Light-transmitting design part 16 and light-shielding background part 17
Can be formed by a method such as a thin film forming technique or a thick film forming technique. For example, when the translucent design portion 16 is made to be a light color and the light-shielding background portion 17 is made to be a dark color, the translucent design portion 16 has an ink having a high light reflectance (for example, white ink).
And ink having a low light reflectance (for example, black ink) is used for the light-shielding background portion 17. Then, a film thickness capable of transmitting the light of the surface light source 13 through the translucent design portion 16 is formed on the front surface of the transparent body 12 by a thick film forming technique such as screen printing.

Surface light source 13 for illuminating design display layer 15 at night
Although various types of surface light sources can be used, an organic dispersion type EL is preferable in terms of cost and handling. This organic dispersion-type EL is obtained by dispersing and bonding an EL luminous body with an organic binder and sealing the film sheet. The light-transmitting design portion 16 is processed into a size that can be uniformly illuminated from behind, and the base is processed. 19 is attached to the surface of the display body 11 side.

A lens 18a for expanding the light of the surface light source 13
Is disposed between the body 12 and the surface light source 13, and the body 1
2 can be attached so as to be in contact with the inside of the back surface. The lens 18a is a plano-convex single lens with a small focal length designed to focus immediately after passing through the translucent design portion 16. In such a configuration, the light of the surface light source 13 converges and passes through the white translucent design portion 16, and then slightly from the translucent design portion 16 to the visual position 20.
Focus on the side. The focused light travels while diverging to a visual position 20 where the viewer is located (for example, approximately 30 cm away from the design display layer 15).

In the above case, it passes through the upper end of the lens 18a.
The light of the surface light source 13 is refracted downward to form a uniform visual lower limit line 2.
1b, and intersects the viewer's visual position 20 at the uniform visual limit 20b. Here, the uniform visual lower limit line 21
b is a lower limit line where the brightness of the translucent design portion 16 looks uniform. When the viewer is at the visual position 20 above the uniform visual limit point 20b, in order to see only the surface light source 13,
It is felt that the translucent design portion 16 is uniformly illuminated. On the other hand, when the viewer is at the visual position 20 below the uniform visual limit point 20b, the translucent design is used to view a portion of the surface light source 13 and a portion (for example, the switch element 14) deviating from the surface light source 13. It is visually perceived that the portion 16 has uneven brightness.

Similarly, the light emitted from the surface light source 13 and passing through the lower end of the magnifying lens 18a is refracted upward, travels along the uniform visual upper limit line 21a, and the visual position 20 of the viewer and the uniform visual limit point. Intersect at 20a. Here, the uniform visual upper limit line 21a is an upper limit line in which the brightness of the translucent design portion 16 looks uniform. When the viewer is at the visual position 20 below the uniform visual limit point 20a, he or she feels that the translucent design portion 16 is uniformly illuminated in order to see only the surface light source 13. On the other hand, when the viewer is at the visual position 20 above the uniform visual limit point 20a, the viewer sees a part of the surface light source 13 and a part outside the surface light source 13 (for example, the switch element 14). It is visually perceived that the light design portion 16 has uneven brightness.

That is, in the above-mentioned surface light source illumination display device, the viewer can observe the uniform visual upper limit line 21a and the uniform visual lower limit line 2a.
1b and only within the uniform viewing angle (β)
Visually, the translucent design part 16 has a uniform brightness.
When the user is at a position deviating from the angle, the user perceives that the translucent design portion 16 has uneven brightness. Therefore,
The uniform viewing angle (β) at which the translucent design portion 16 is viewed as having uniform brightness is larger than the uniform viewing angle (α) of the conventional surface light source illumination display device.

The lens 18a can be mounted inside the rear surface of the body 12 and at a position shifted toward the surface light source 13. In this case, as the lens 18a, a convex single lens that focuses immediately before or immediately after transmission through the translucent design portion 16 can be used. Translucent design part 16
Surface light source 1 when a convex lens focuses just before passing through
The light exiting from 3 and passing through the magnifying lens 18a is focused before the translucent design portion 16, then passes through the translucent design portion 16, and proceeds to the visual position 20 while diverging. Lens 18a
Is abutted behind the body 12, the uniform visual angle (β) is larger than the uniform visual angle (α) of the conventional surface light source illumination display device.

As the magnifying lens, a concave single lens 18a (not shown) can be used. Concave single lens 1
Regardless of the position of the surface 8a between the body 12 and the surface light source 13, the light of the surface light source 13 passes through the translucent design portion 16 while diverging without focusing, and The visual position 20 is reached. Therefore, the convex single lens 18a
As in the case of (1), the uniform viewing angle (β) is larger than the uniform viewing angle (α) of the conventional surface light source illumination display device.

As shown in FIG. 4, a micro lens 18b can be used as a magnifying lens. The micro lens 18b is configured such that each of the micro lenses has a convex shape or a concave shape, and they are arranged vertically and horizontally in a plane. As in the case of the single lens described above, the micro lens 18b is used by being attached between the body 12 and the surface light source 13. For example, a microlens 18 b composed of a biconvex lens that focuses before passing through the translucent design portion 16 is attached to the inside of the body 12. In this case, the surface light source 1
3, the light passing through the microlens is focused in front of the translucent design portion 16 and transmitted through the translucent design portion 16 while diverging, similarly to the single lens 18a shown in FIG. Go to 20. Therefore, the observer can view the uniform visual upper limit line 21.
a and the uniform visual angle (γ) formed by the uniform visual lower limit line 21b
When it is inside, it is visually perceived that the translucent design portion 16 has uniform brightness. Further, when the microlenses 18b are used, the light of the surface light source 13 is emitted from each microlens, so that the translucent design portion 16 looks more uniform than when the single lens 18a is used.

Further, a plurality of push-type switch elements 14 as shown in the figure can be provided between the plate-like base 19 and the display body 11 to provide a switch function to the surface light source illumination display device. The switch element 14 is disposed such that one end is mounted on the base 19 and the other end is supported by the display 11. In such a configuration, when the display body 11 is lightly pushed or released with the hand, the switch element 14 expands and contracts, and a contact (not shown) is turned on and off.

Although the switch operation knob for an automobile has been described above as a preferred embodiment of the surface light source illumination display device, the type of the surface light source illumination display device (for example, electric appliances, cellular phones, etc.) The type of surface light source (for example, organic thin-film EL, inorganic thin-film EL), the shape, optical characteristics, and mounting position of the magnifying lens are not limited to the above embodiments.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a conventional surface light source illumination display device.

FIG. 2 is a perspective view showing a conventional surface light source illumination display device with a part thereof cut away.

FIG. 3 is a cross-sectional view showing a surface light source illumination display device according to an embodiment of the present invention.

FIG. 4 is a sectional view showing a modification of the magnifying lens of FIG.

[Description of Signs] 11 Display body 12 Body 13 Surface light source 14 Switch element 15 Design display layer 16 Translucent design section 17 Light-shielding background section 18a Single lens (magnifying lens) 18b Micro lens (magnifying lens) 19 Base 20 Viewer Visual position 20a, 20b Uniform visual limit point 21a Uniform visual upper limit line 21b Uniform visual lower limit line β, γ Uniform visual angle

Claims (3)

[Claims] 1. A display (11) comprising: a display (11); and a surface light source (13) for illuminating the display (11) from behind.
The display body (11) has a surface light source in which a design display layer (15) including a translucent design part (16) and a light-shielding background part (17) is formed on the front surface of the body (12). In a lighting display device, a magnifying lens (18) for enlarging a uniform visual angle (β, γ)
a, 18b) is provided between the body (12) and the surface light source (13). 2. The surface light source illumination display device according to claim 1, wherein the magnifying lens (18a) is a single lens. 3. The surface light source illumination display device according to claim 1, wherein the magnifying lens is a micro lens array.