JP2001242808A - Display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the visibility of display by constituting a display panel in such a manner that only the specific one point corresponding to a lighted light source of the display panel glitters sharply. SOLUTION: A display 2 having a spot light source, such as an LED, is disposed as the light source 4 inside the transparent or translucent panel 1. This panel 1 is provided with light shielding rib walls 5 in the position corresponding to the side of the light source 4 on the backside 1b of the panel to direct the light emission direction of the light source 4 toward the direction heading the surface 1a of the panel. The central part 1c of the segment of the backside 1b of the panel 1 facing the light source 4 is formed approximately parallel to the front surface 1a and the segment slightly deviating from this central part 1c is formed as a sloping part 1d inclined in the direction of the light source 4, by which a recess 6 consisting of the central part 1c, the sloping part 1d and the light shielding rib walls 5 is formed. The light source 4 is disposed within this recess 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display panel used for an operation section of various electronic devices including an electronic musical instrument such as an electronic organ and an electronic piano.

[0002]

2. Description of the Related Art For example, an operation section or an operation panel of an electronic organ or an electronic piano is provided with a display panel having a display provided with a light source at a position corresponding to each key. There are lights that indicate the key to be operated or the position of the operated key by lighting. Alternatively, when each key of the control panel is turned on, it is displayed by turning on a light source.

[0003] As a conventional general structure of such a display panel, for example, as shown in FIG. 8, a light emitting diode (point light source) as a point light source is provided inside a transparent colored resin panel 100 (back side). An LED (LED) 101 is arranged on a substrate 102 and used. And LED
When the light 101 is turned on, a portion 100a (shown by a broken line) of the transparent colored resin panel 100 facing the lighted LED 101 appears to glow brightly. Transparent colored resin panel 100
For example, a material obtained by coloring a polystyrene with a pigment is used.

[0004]

However, in such a conventional display panel, a portion opposed to a point light source such as an illuminated LED shines brightly, but its spread is large.
In addition, the peripheral portion has low brightness and is unclear, and when viewed from different angles, a portion different from the intended position of the display panel may appear to shine. In addition, since the light source itself is directly visible, the light source may appear to shine at two places depending on the viewing angle, and there is a risk of misperception.

The present invention has been made to solve the above-mentioned problems in the conventional display panel.
It is an object of the present invention to enhance visibility of a display so that only one specific portion corresponding to a light source lit on a display panel shines sharply.

[0006]

A display panel according to the present invention is a display panel in which a display is provided inside a transparent or translucent panel. The light source is a point light source, a light-blocking rib wall is provided on the side of the light source of the panel, the light emission direction of the light source is set to a direction toward the surface of the panel, and the center of the rear surface of the panel facing the light source is the center of the front surface. By forming a part slightly deviated from the center part in an inclined part inclined in the direction of the light source, a concave part composed of the center part, the inclined part, and the light-shielding rib wall is formed. The light source is provided in a concave portion.

[0007] Alternatively, in a display panel in which a display is provided inside a translucent panel subjected to smoke processing, a light source of the display is a point light source, and a light source is provided beside the light source of the panel. A light-shielding rib wall is provided integrally with the panel, the light emission direction of the light source is set to a direction toward the surface of the panel, the center of a portion of the rear surface of the panel facing the light source is substantially parallel to the surface, and the outside of the light-shielding rib wall. By forming the light source to be thinner than the thickness of the portion, a concave portion may be formed by the central portion of the portion facing the light source and the light-shielding rib wall, and the light source may be disposed in the concave portion.

[0008]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is an enlarged sectional view showing a main part of one embodiment of a display panel according to the present invention.

This display panel has a light emitting diode 4 as a light source 4 on a printed circuit board (hereinafter simply referred to as a “substrate”) 3 inside a transparent or translucent panel 1 (back side, lower side in FIG. 1). A display 2 is provided in which a number of point light sources such as (LED) and miniature light bulbs are arranged in a direction perpendicular to the paper surface. In FIG. 1, the upper side is the viewing side that is seen by a person outside.

The panel 1 is made of a transparent material such as polystyrene or acrylic resin, and may be entirely transparent.
The transparent resin is formed by mixing light scattering particles, the panel surface 1a is formed into a rough surface (ground glass), or a smoke treatment such as coating a light scattering layer such as milky white is performed. It is preferable to make the display part transparent or at least a display part in a predetermined area facing the light source 4 to be translucent. Alternatively, a transparent or translucent colored panel may be formed by mixing a transparent resin with a pigment for coloring.

A light-shielding rib wall 5 is provided on the panel 1 at a position corresponding to a side of the light source 4, and a light-emitting direction of the light source 4 (light-emitting portion 4
1 is a direction toward the front surface 1a of the panel 1 (a direction indicated by an arrow A in FIG. 1), and a central portion 1c of a portion of the back surface 1b of the panel 1 facing the light source 4 is substantially parallel to the front surface 1a. And a concave portion formed of a central portion 1c, an inclined portion 1d, and a light-shielding rib wall 5 by forming a peripheral portion or a side portion slightly shifted from the central portion 1c in the direction of the light source 4. 6 is formed, and the light source is disposed in the concave portion.

The center 1c of the portion of the back surface 1b of the panel 1 facing the light source 4 need only be substantially parallel to the front surface 1a, and need not be a completely parallel plane. For example, a fine wave surface, a gentle roof surface, or a gentle concave surface may be used. Similarly, the inclined portion 1d may be any surface that is inclined so as to approach the light source 4 from the side of the center portion 1c toward the light shielding rib wall 5, and may be a fine wavefront or a gentle concave surface.

The light source 4 uses an LED in the illustrated example, and includes a light emitting portion 4a, a base portion 4b, and leg portions 4 supporting the light emitting portion 4a and the base portion 4b.
c and the circuit on the substrate 3 and the light emitting portion 4a in the leg portion 4c.
A lead wire for connecting the element inside is provided.

According to the display panel configured as described above,
When the light source 4 is turned on, of the light emitted from the light emitting point P, the light rays a and b incident on the central portion 1c of the portion of the back surface 1b of the panel 1 facing the light source 4 are substantially perpendicular to the central portion 1c. Since the light is incident (the incident angle is zero or extremely small), the light passes through the panel 1 almost as it is. Light rays c, d, and e incident on the inclined portion 1d are more likely to diverge due to an action similar to that of the concave lens at this portion, and the angles of incidence from the inside of the panel 1 having a large refractive index to the outside (air) having a small refractive index. Becomes larger, and as the inclination angle from the light emitting direction indicated by the arrow A becomes larger, the ratio of the amount of light reflected and returned on the surface 1a of the panel 1 increases, and the amount of light emitted to the outside (upward in FIG. 1) decreases. .

Then, the light beams f,
Since g is refracted by the light incident surface to the light-shielding rib wall 5, the angle of incidence θ from the inside of the panel 1 to the outside becomes larger than the critical angle (about 40 ° to 45 ° depending on the material of the panel 1). All of the light is reflected by the surface 1a of the panel 1,
Will not be ejected to the outside. Although FIG. 1 shows only the light rays on the left side of the light emission direction (arrow A) of the light source 4, the light rays radiated on the right side, or the surrounding area when the light shielding rib wall 5 is formed around the light source 4. The same applies to the light rays radiated to.

Accordingly, the lighting of the light source 4 causes the panel 1
The light beam emitted from the outside of the light-shielding rib wall 5 is strong at the central portion 1c, gradually weakened at a portion corresponding to the inclined portion 1d around the central portion 1c, and hardly emitted to the outside of the light-shielding rib wall 5. Due to the scattered light in the panel 1 due to the light emitted to the outside, the central portion 1
The portion corresponding to c is the brightest, the portion inside the light-shielding rib wall 5 around the portion looks bright next, and the maximum illuminating range is the range indicated by S, and the outside does not shine.

Further, most of the light rays incident on the light-shielding rib wall 5 from the light source 4 are reflected on the surface of the light-shielding rib wall 5 because the incident angle is relatively large. Inject to the viewing side through the part 1d,
Since there is also an effect of contributing to the display, only the central portion 1c and its surrounding region appear brighter. Further, the light-shielding rib wall 5 also has an effect of partially absorbing the light that has entered the interior, and further, since the color of the panel (including white turbidity) becomes dark on the light-shielding rib wall 5 of the panel 1, light is difficult to transmit. There is also action.

With these arrangements, almost no light leaks to the outside of the light-blocking rib wall 5 as viewed from the surface 1a side of the panel 1, and extremely clear and sharp display can be achieved. In addition, even when the panel 1 is viewed from an oblique direction, the light-shielding rib wall 5 prevents the light source 4 from being directly seen.

FIG. 5 shows the relationship between the spread of the illuminated range and the light intensity from the position corresponding to the light emitting point P on the panel 1 in the case of the display panel of this embodiment (curve F) and in the case of the conventional display panel. This is shown in comparison with the case (curve G). From FIG. 5, it can be seen that the display panel of this embodiment shines brighter in a narrower area than the conventional display panel.

In the example shown in FIG. 1, the light source 4 of the panel 1
Is thinner than the thickness t2 of the portion outside the light-shielding rib wall 5, which is also desirable for brightening the central portion 1c, but is not an essential requirement. . By changing the distance between the central portion 1c and the light source 4, the inclination angle of the inclined portion 1d, and the area ratio between the central portion 1c and the inclined portion 1d, the size of the illuminated area to be specified can be variously changed. Can be.

For example, the light emitting portion 4a of the light source 4 is inserted deeper into the concave portion 6 than shown in FIG. 1, and the inclined portion 1d and the light emitting portion 4a of the light source 4 are arranged close to each other. When the thickness of the central portion 1c of the portion to be reduced is reduced, a narrower range can be made brighter.

Next, an example of a control panel of an electronic musical instrument using the display panel will be described with reference to FIGS. 2 is a rear view of only the panel side of the control panel, FIG. 3 is a side view as viewed from the direction of arrow B in FIG. 2, and FIG. 4 is a cross section taken along line CC in FIG. FIG. 3 is a cross-sectional view showing a state in which a control panel (including a display panel) is configured in combination with a display and the like. In these drawings, parts corresponding to those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 2, a transparent or translucent panel 1 is shown.
A pair of light-shielding rib walls 5 and 5 are provided in parallel on the back surface of the light-emitting device 1 with an interval at which a light source 4 such as an LED can be inserted. Although the light-shielding rib wall 5 is formed integrally with the panel 1, the light-shielding rib wall 5 may be formed in a plate shape with another member and adhered to the back surface 1 b of the panel 1. In this example, a common pair of rib walls 5, 5 and a pair of light shielding rib walls 5 ', 5' for one light source are provided over four light sources.

In the gap between the light-shielding rib walls 5, 5 and 5 ', 5', an oblong inclined portion 1d is formed corresponding to the position of each light source 4 when viewed from the back surface. Then, the position corresponding to each inclined portion 1d (right side in FIG. 2)
Is provided with an operator fixing rib 12 and an operator hole 11. Further, a board mounting boss 1 for screwing the board is provided.
3 are provided at required places. Also, as shown in FIG. 3, mounting holes 2 on the main panel are provided on both sides of the panel 1.
A mounting plate 25 having 5a protrudes.

The substrate 3 is fixed to the back side of the panel 1 by a substrate mounting boss 13 and mounting screws 20 as shown in FIG. 4, and each light source (L in this example) supported on the substrate 3
ED) 4 is inserted and disposed between the pair of rib walls 5 and 5 and between the pair of rib walls 5 'and 5' where each inclined portion 1d is formed.

As indicated by the imaginary lines, a switch 21 corresponding to each light source 4 and a control 22 for operating the switch are provided on the substrate 3. It protrudes upward through the operation hole 11. The base end of each operation element 22 is movably locked to the operation element fixing rib 12 within a predetermined angle rotation range.

When the operator 22 is pressed, the switch 21 is turned on, and the corresponding light source 4 is turned on. Thereby, only the portion where the center portion 1c between the light shielding rib walls 5 and 5 and the inclined portion 1d is formed shines brightly. The operation is as described above, and the description is omitted. The switch 21 is, for example, a tone selection switch. When the switch 21 is turned on, a specific tone (for example, a grand piano) is selected, and the light source 4 indicating the selected tone is turned on.

In this embodiment, the light-shielding rib wall 5 is formed in a parallel plate shape. However, the light-shielding rib wall 5 may be formed in a cylindrical shape, an elliptic cylinder, a long cylinder, a rectangular cylinder or the like so as to surround each light source 4. Thus, a clearer display can be performed. FIG. 6 shows an example in which an elongated cylindrical light-shielding rib wall 15 is provided on the back surface of the panel 1 so as to surround the light source 4. An illuminated display in an oval region Q is obtained by the light source 4 such as a round LED. Can be.

Next, another embodiment of the display panel according to the present invention will be described with reference to FIG. The display panel shown in FIG. 7 has a facing portion (including a central portion) 1 facing the light source 14 on the back surface 1b of the translucent panel 1 'subjected to the smoke processing.
e is a plane substantially parallel to the surface 1a, and a light-shielding rib wall 15 is formed integrally therewith around the panel 1 '.

By forming the thickness t1 of the opposing portion 1e of the panel 1 'to be smaller than the thickness t2 of the outer portion of the light-shielding rib wall 15, a concave portion 16 is formed by the opposing portion 1e and the light-shielding rib wall 15. The point light source LE is provided in the recess 16.
A light source 14 such as D or a miniature light bulb is disposed so that the light emission direction (the direction of the arrow A whose tip is directed in the figure) is directed toward the surface 1a of the panel 1 '.

Since the facing portion 1e of the panel 1 'may be substantially parallel to the front surface 1a, it need not be a completely parallel plane.
For example, a fine wave surface, a gentle roof surface, or a gentle concave surface may be used. Further, in this example, the inclined portion 1d provided in the panel 1 of the above-described embodiment is not provided, and the light source 14 is inserted deeply into the concave portion 16. However, only the central portion of the facing portion 1e of the panel 1 'may be formed as a plane substantially parallel to the surface 1a, and an inclined portion may be provided around the central portion as in the above-described embodiment.

The light source 14 is an LED in this example. The light source 14 is firmly fixed and supported on the substrate 3 by a spacer / light source fixing member 17, and corresponds to a plurality of switches (not shown) on the substrate 3, respectively. Are provided side by side in a direction perpendicular to.

According to the display panel configured as described above,
When the light source 14 is turned on, of the light emitted from the light emitting point P, the light beams a, b, and c incident on the facing portion 1e facing the light source 14 on the back surface 1b of the panel 1 'enter the panel 1'. The light is refracted when and when it is emitted, but the incident light and the emitted light are in the same direction. However, since the angle of incidence θ from the inside of the panel 1 ′ having a large refractive index to the outside on the viewing side (air having a small refractive index) increases as the angle of inclination from the direction of the arrow A at the center increases, the light is reflected by the surface 1 a and reflected inside. The ratio of the amount of light returned to is increased.

The light beam d entering the corner between the opposing portion 1e and the inner surface of the light-shielding rib wall 15 also travels substantially straight and enters the panel 1 ', and is partially refracted and emitted to the outside on the viewing side. However, most are reflected by the surface 1a and returned inside. Light rays e, which enter the panel 1 'from the inner surface of the light-blocking rib wall 15,
f is totally reflected by the surface 1a because the incident angle θ to the outside (air) is larger than the critical angle, and is not emitted to the viewing side.

FIG. 7 also shows only light rays on the left side of the light emission direction of the light source 14 (arrow A). However, since the light-shielding rib wall 15 is formed around the light source 14, it is radiated in any direction around the entire circumference. The same is true for the light beam.

Accordingly, the light beam emitted from the panel 1 'to the outside by turning on the light source 14 is strong at the central portion of the facing portion 1e facing the light source 14, becomes gradually weaker around the central portion, and becomes light outside the light shielding rib wall 15. Almost no injection. The portion corresponding to the central portion of the facing portion 1e is the brightest due to the scattered light in the panel 1 'due to the light emitted to the outside,
The surroundings then appear bright and the maximum illumination range is S
, And the outside does not shine.

Further, most of the light rays incident on the light-shielding rib wall 15 from the light source 14 are reflected on the surface of the light-shielding rib wall 15 due to a relatively large incident angle. There is also an effect of emitting light to the side and contributing to display, so that the area of the facing portion 1e looks brighter. Further, the light-shielding rib wall 15 also has an effect of partially absorbing the light that has entered inside, and furthermore, the light-shielding rib wall 15 of the panel 1 ′.
In the upper part, the color of the panel (including white turbidity) is darkened, which also has the effect of making light difficult to transmit.

As a result, there is almost no leakage of light to the outside of the light-shielding rib wall 15 as viewed from the surface 1a side of the panel 1 ', and if the light-shielding rib wall 15 is cylindrical, only the circular area inside the wall is limited. If the light-blocking rib wall 15 is an elliptical cylindrical shape, only the inner elliptical area inside the oval cylindrical wall glows brightly and clearly,
Sharp display becomes possible. In addition, even when the panel 1 'is viewed from an oblique direction, the light source 14 is not directly seen due to the presence of the light-blocking rib wall 15, so that it is possible to prevent the two places from shining and appearing to cause an erroneous recognition.

Also in this embodiment, the size and shape of the illuminated area to be specified can be variously changed by changing the shape of the facing portion 1e, the distance from the light source 14, the shape of the light shielding rib wall 15, and the like. .

[0040]

As described above, the display panel according to the present invention is designed such that the light source of the display device disposed inside the transparent or translucent panel is turned on, so that only the specific portion corresponding to the light source on the panel is turned on. Since the light is shined sharply, the visibility of the display can be improved. In addition, since only one location appears to shine depending on the lighting of one light source from any direction, there is no danger of misidentification. Therefore, the usability and texture of the operation unit of an electronic device such as an electronic musical instrument can be improved.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view showing a main part of one embodiment of a display panel according to the present invention.

FIG. 2 is a rear view of only a panel side showing an example of a control panel of an electronic musical instrument using the display panel shown in FIG.

FIG. 3 is a side view as viewed in the direction of arrow B in FIG. 2;

FIG. 4 is a cross-sectional view showing a state in which a control panel is configured by combining a cross-section along line CC in FIG.

FIG. 5 is a diagram for explaining effects of the display panel shown in FIG. 1;

FIG. 6 is an explanatory diagram showing the relationship between the shape of a light-blocking rib wall of a display panel and the shape of a display area according to the present invention.

FIG. 7 is an enlarged sectional view showing a main part of another embodiment of the display panel according to the present invention.

FIG. 8 is a perspective view showing an example of a conventional display panel.

[Explanation of symbols]

1, 1 'panel, 1a front surface, 1b back surface, 1c central portion, 1d inclined portion, 1e opposed portion, 2, 2' display, 3 printed circuit board (substrate), 4, 14 …light source,
4a: Light-emitting portion, 4b: Base portion, 4c: Leg portion, 5,
5 ', 15: light shielding rib wall, 6, 16: concave portion, 11: operator hole, 12: operator fixing rib, 13: board mounting boss, 1
7 ... spacer and light source fixture, 21: switch, 22 ... operator, 25 ... mounting plate

Claims (2)

[Claims] 1. A display panel in which a display is disposed inside a transparent or translucent panel, wherein a light source of the display is a point light source and corresponds to a side of the light source on a back surface of the panel. A light-shielding rib wall is provided at a position where the light source emits light in a direction toward the surface of the panel, and a central portion of a portion of the back surface of the panel facing the light source is formed substantially parallel to the surface, and the center is formed. By forming a portion slightly deviated from the portion on the inclined portion inclined in the direction of the light source, a concave portion composed of the central portion, the inclined portion, and the light shielding rib wall was formed, and the light source was disposed in the concave portion. A display panel, characterized in that: 2. A display panel in which a display is provided inside a translucent panel subjected to smoke processing, wherein a light source of the display is a point light source, and a side of the light source on a back surface of the panel. A light-shielding rib wall is provided integrally with the panel at a position corresponding to the light source, a light emitting direction of the light source is a direction toward the surface of the panel, and a central portion of a portion of the back surface of the panel facing the light source is substantially the same as the front surface. By forming the light-shielding rib wall in parallel and thinner than the thickness of the outer part of the light-shielding rib wall, a concave portion was formed by the central portion of the portion facing the light source and the light-shielding rib wall, and the light source was disposed in the concave portion. A display panel, characterized in that: