JP2000089693A - Flat panel display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flat panel display reducing influence of a beam from another light emitting element without thinning a glass panel even when fined light emitting elements are arranged at a narrow pitch. SOLUTION: The flat panel display 10 is constituted so that the light emitting elements 12 are formed in matrix at a fixed interval on an A surface on a glass panel 11 having fixed thickness, and fixed depth grooves 13 is formed from a B surface being a display surface of a side opposite to the A surface being the light emitting element forming surface of the glass panel 11 toward a gap between adjacent light emitting elements 12 on the A surface with the same width as the gap between the adjacent light emitting elements 12 or with the width narrower than the gap, and the depth of the groove 13 is adjusted so as to form an optical path so that a light emitting beam from the light emitting element 12 doesn't transmit through the B surface being the display surface excepting the area of the light emitting element 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat panel display in which light emitting elements are formed in a matrix on one side, and more particularly to a flat panel display which is less affected by light emitted from other light emitting elements.

[0002]

2. Description of the Related Art FIG. 6 is a schematic plan view of a conventional flat panel display, and FIG. 7 is a schematic sectional view taken along the line YY 'of FIG. Conventionally, in a flat panel display 60, one surface A of a flat glass panel 61 is used.
A plurality of light emitting elements 62 were formed in a matrix on the surface 61a as organic EL elements, and light emitted from the light emitting elements 62 passed through the glass panel 61 and was emitted to the outside from the B surface 62b serving as a display surface.

[0003]

In this case, the light emitting element 6
The light from 2 spreads out from the original light emission position, passes through the glass panel 61, and is emitted to the outside, as indicated by the arrow in FIG. For this reason, there is a problem that the straight light from each light emitting element 62 is affected by the light from the surrounding light emitting elements 62 and the overall resolution is reduced.

[0004] For example, as shown in FIG.
0 μm and the gap between the light emitting elements is 40 μm.
The size r1 of the transmission area on the surface 62b is
It spreads as shown by the following equation defined by a thickness t1 of 1 and a refractive index n1 of glass and a refractive index n2 of air.

R1 = 80 μm + 2 × t1 × n2 / n1 Specifically, when numerically expressed, t1 = 1 mm, n1 = 1.6,
If n2 = 1, r1 = 1.33 mm, which is about 17 times the width of the light emitting element 62.

As can be seen from the above equation, the glass panel 6
If the thickness t1 of 1 is reduced, the width of the spread becomes narrower, but there is a limit in terms of the strength of the glass panel 61.

An object of the present invention is to provide a flat panel display which can reduce the influence of light from other light emitting elements without reducing the thickness of the glass panel even when the miniaturized light emitting elements are arranged at a narrow pitch. To provide.

[0008]

A flat panel display according to the present invention is a flat panel display comprising a glass panel and a plurality of light-emitting elements arranged in a matrix on one surface of the glass panel. From the surface of the panel opposite to the surface on which the light emitting elements are provided, toward the gap between the adjacent light emitting elements, a groove having a width equal to or less than the gap between the adjacent light emitting elements has a thickness of 3 mm of the thickness of the glass panel. It is formed on the glass panel at a depth of at least two-thirds.

A second glass panel may be attached to the surface of the glass panel on which the groove is formed, and the width of the light emitting element is one.
It may be 00 μm or less.

When the width of the groove is w2, the width of the light emitting element is w1, the pitch of the light emitting element is p, the thickness of the glass panel is t1, the refractive index of glass is n1, and the refractive index of air is n2,
The depth d2 of the groove is: d2 = t1- {0.5 × (p−w1 + w2)} × tan
{Sin ⁻¹ (n2 / n1)} is preferable.

The surface of the glass panel in contact with the groove may be mirror-finished, or a metal film or a light absorbing film may be formed on the surface of the glass panel in contact with the groove.

In another aspect, a glass panel having two layers, a first glass panel and a second glass panel, which are bonded to each other, and a plurality of glass panels arranged in a matrix on a non-bonding surface of the second glass panel. A flat panel display comprising: a light-emitting element; and a light-emitting element between adjacent light-emitting elements corresponding to a gap between the light-emitting elements formed on the second glass panel from the joint surface of the first glass panel. A groove having a width equal to or less than the gap is formed in the first glass panel at a depth of at least twice the thickness of the second glass panel. By forming the groove having the structure of the present invention in the glass panel in this manner, it is possible to reduce or block light leakage from an adjacent light emitting element. Specifically, the light emitted from the adjacent light emitting element incident on the boundary surface of the groove is guided in the glass panel in a direction parallel to the light emitting element without being reflected by the display surface by adjusting the depth of the groove. It was realized by that.

As a result, the display performance of the flat display, particularly the definition, has been improved, and only the light emitted from the original light emitting element region can be guided in parallel to the display surface.

[0014]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic plan view of the flat panel display according to the first embodiment of the present invention, and FIG. 2 is a schematic partial cross-sectional view taken along line XX ′ of FIG.

In the flat panel display 10 of the first embodiment, the light emitting elements 1 are arranged in a matrix at regular intervals on an A surface 11a on a glass panel 11 having a constant thickness.
2 which is a display surface opposite to the A surface 11a which is the light emitting element forming surface of the glass panel 11.
b, a groove 13 having a constant depth is formed in the same width as the gap between the adjacent light emitting elements 12 or a width smaller than the gap toward the gap between the adjacent light emitting elements 12 on the A surface 11a. I have. In the first embodiment, the surface of the glass panel 11 in the groove 13 is mirror-finished by a chemical treatment or the like.

The depth of the groove 13 is adjusted so as to form an optical path such that light emitted from the light emitting element 11 does not pass through the surface B other than the area of the light emitting element 11 to the display surface B. .

Light emitting device 11 according to the first embodiment of the present invention
Will be described with reference to FIG. Groove 13
As described above, the light emitting elements 1 adjacent to each other from the B side 11b to the A side 11a have a width equal to or smaller than the gap between the light emitting elements 11 as described above.
It is formed toward the gap between the two.

In the first embodiment, the depth of the groove 13 is determined by the width and pitch of the light emitting element 12, the width of the groove 13, and the glass panel 11.
And the most effective depth determined by the refractive index of the air and the refractive index of the air. That is, the distance from the side surface of the groove 13 to the side surface of the light emitting element 12 adjacent to the groove 13 across the groove 13 is d1.
＝= 0.5 × (pitch + width of groove−width of light emitting element)｝,
The thickness of the glass panel 11 is t1, and the refractive index of the glass is n.
1. Assuming that the refractive index of air is n2, the object can be achieved by setting the depth of the groove 13 to d2 or more calculated by the following equation.

D2 = t1−d1 × tan {sin ⁻¹ (n2 / n1)} This is based on the Fresnel's equation, and defines the condition of the critical angle at which all the light incident on the groove 13 is totally reflected on the glass surface of the groove. This is a calculation formula for calculating the depth d2 of the groove 13 to be filled.
If 3 is deep, the light incident on that part of the side of the groove
The light passes through the side surfaces of the groove one after another without being totally reflected by the surface 3 as shown in the optical path described later. When the groove 13 is shallower than this, the light is totally reflected by the groove 13 of the adjacent pixel as shown in the optical path described later, and is emitted to the outside from the B surface 11b immediately below the adjacent pixel of the original light emitting element. Leaks light.

The optical paths of emitted light emitted from the light emitting element 12 at various angles will be described in detail with reference to the optical paths indicated by reference numerals 1 to 3 in FIG.

The light path that has spread most horizontally is reflected or diffused by the upper surface of the groove 13 and
Finally, the light is emitted from the side surface of the glass panel 11 into the air.

Since d2 is set in the optical path connecting the end of the light emitting element 12 to the end of the groove 13 so that θ1 becomes the critical angle, the light between the optical paths is adjacent to the light emitting element 12 Incident on the side surface of the groove 13, propagates in the horizontal direction through the glass panel 11 under the influence of the refraction by the groove 13, and exits at a position far away from the original light emitting element 12, or If it is thicker, it is emitted into the air from the side of the glass panel 11.

Light incident on the upper surface of the groove 13 immediately below the light emitting element 12 repeats total reflection inside the groove because θ 1 is a critical angle, and is emitted from the opening of the groove 13. If the depth of the groove 13 is larger than the value of d2 in the above equation, light incident at a critical angle or less takes the same optical path as that of the above.

Glass panel 1 in the region of light emitting element 12
The light that has entered the side surface on the groove side at a critical angle or less is emitted from the B surface 11b, which is the display surface of the glass panel 11, while being irregularly reflected on the wall surface of the glass panel 11 as shown in the optical path.

Light emitted from the light emitting element 12 at an angle close to 90 degrees is directly transmitted to the glass panel 11 as shown in the optical path.
Are emitted from the B surface 11b, which is the display surface of.

If the depth of the groove 13 is shallow as shown by the broken line in the figure, the light emitting element 12
Is directly incident on the glass panel 11 in the region of the adjacent light emitting element 12 and is reflected on the wall surface to be adjacent to the light emitting element 1.
The light exits from the B surface 11b of the glass panel 11 in the area 2. This causes light leakage and reduces the definition of the flat display.

As described above, by making the groove 13 deep enough, the light emitted from the adjacent light emitting element 12 propagates in the lateral direction of the glass panel and becomes leaked light to lower the definition of the flat display. There is no.

More specifically, the width of the light emitting element 12 is 80 μm, the gap between the light emitting elements 12 is 40 μm,
3, the width of 40 μm, the thickness of the glass panel 500 μm,
Assuming that the refractive index of the glass panel is 1.6 and the refractive index of air is 1, d2 = 500−40 × tan {sin ⁻¹ (1 / 1.6)} = 500−40 × tan (38.6 °) = 500-31.9 = 468.1 μm.

By forming a groove deeper than the depth of 468.1 μm, light from a light emitting element arranged adjacently does not leak.

If the light of the light emitting element 12 is at least reflected on the B side 1 of the glass panel 11 in the region of the adjacent light emitting element 12
When the condition of the depth d2 of the groove 13 for preventing direct irradiation of 1b is obtained, the width of the light emitting element 12 is w1, the width of the groove 13 is w2, the pitch of the light emitting element 12 is p, and the thickness of the glass panel 11 is t.
Assuming that 1, d2 = t1 × 2 (p−w2) ÷ (3p−w1−w2), and if the light emitting element 12 has a width of 80 μm and the light emitting element 1
If the gap between the two is 40 μm and the width of the groove 13 is 40 μm, then d2 = t1 × 2/3. Therefore, it is desirable that the depth of the groove 13 is at least 2/3 or more of the thickness of the glass panel.

FIG. 3 is a schematic partial sectional view of a flat panel display according to a second embodiment of the present invention. In the second embodiment of the present invention, grooves are formed in the same manner as in the flat panel display of the first embodiment.
In the groove 33 of the second embodiment, the metal film 34 is formed on the surface of the glass panel 31 in the groove 33 without performing mirror finishing.
Is formed, and the emitted light is totally reflected on this surface.

The glass panel 31 having the groove 33 formed by the metal film 34
When formed on the surface, the leaked light from the adjacent light emitting element 32 is totally reflected by the metal film 34 of the groove 33, so that the emitted light of the adjacent light emitting element 32 is emitted from the display surface (plane B) that is far away. Can be prevented. However, this is based on the premise that the light emitted from the adjacent light emitting element 32 is sufficiently attenuated in the glass panel 31. Further, since the metal film 34 blocks incidence of external light, it also has an effect of improving the contrast of panel display.

The same effect can be obtained by forming a light absorbing film made of an inorganic or organic film instead of the metal film 34 of FIG. 3 to absorb the emitted light.

In the case of an inorganic or organic absorbing film, the leakage light from the adjacent light emitting element is absorbed by the surface of the groove, so that the leakage light does not go outside. Further, since external light is also absorbed by the absorbing film, the contrast of panel display is improved as compared with the metal film.

FIG. 4 is a schematic partial sectional view of a flat panel display according to a third embodiment of the present invention. In the third embodiment of the present invention, the second glass panel 45 is attached to the B surface 41b which is the display surface of the glass panel 41 in which the light emitting element 42 and the groove 43 are formed as in the first embodiment. I'm matching. Since the glass panel has a double structure, the physical strength can be increased as compared with the first embodiment.

In the third embodiment, the surface of the glass panel 41 in the groove 43 is mirror-finished. However, when a metal film, an inorganic or organic absorption film is formed in the groove 43, the second embodiment differs from the second embodiment. Similarly, the effect of shielding leakage light and improving the contrast can be further improved.

FIG. 5 is a schematic partial sectional view of a flat panel display according to a fourth embodiment of the present invention. In the fourth embodiment of the present invention, the groove 53 of the glass panel 51
Is formed in the opposite direction to the first embodiment, the light emitting element side is formed as an opening, and the interval between the grooves 53 is formed in accordance with the interval between the light emitting elements on the second glass panel 56. The surface of the 53 glass panel 51 is mirror-finished.

The light emitting element 52 is formed on one surface A of the second glass panel 56, and the opposite surface is provided with a gap between the light emitting elements 52 and the groove 53 on the surface of the glass panel 51 having the opening of the groove 53. B surface 51 is formed by bonding together so that the positions are aligned.

The thickness of the second glass panel 56 is the same as the thickness obtained by subtracting the depth of the groove 13 from the thickness of the glass panel 11 of the first embodiment. With this configuration, similarly to the first embodiment, light leaked from the adjacent light emitting element 52 does not go outside. Further, the depth of the groove 53 in the fourth embodiment is approximately equal to the thickness of the second glass panel 56 when the refractive index of the second glass panel 56 and that of the glass panel 51 are the same. If the value is equal to or more than the value obtained by multiplying the length of the element region / the length of the gap between the light emitting elements, the processing of the leaked light from the adjacent light emitting elements is almost completed.

The glass panel 5 having an arbitrary thickness in which the groove 53 is not formed on the surface opposite to the light emitting element 52 at the bottom of the groove 53.
Since the number 1 exists, the strength of the glass panel 51 is enhanced as in the third embodiment.

In the fourth embodiment, the surface of the glass panel 51 in the groove 53 is mirror-finished.
When a metal film or an inorganic or organic absorption film is formed on the substrate, the effect of shielding leaked light and improving the contrast can be further improved as in the second embodiment.

In these embodiments, the grooves are formed in two orthogonal directions so as to surround the light emitting element, but may be formed in one direction depending on the purpose of use.

[0043]

As described above, the flat panel display of the present invention has the effect of reducing or blocking light leaked from adjacent light emitting elements.

This is an effect of the groove of the present invention.
Specifically, the light emitted from the adjacent light emitting element incident on the boundary surface of the groove is guided in the glass panel in a direction parallel to the light emitting element without being reflected by the display surface by adjusting the depth of the groove. It was realized by that.

As a result, the display performance of the flat display, particularly the definition, was improved, and only the light emitted from the original light emitting element region could be guided to the display surface in parallel.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a flat panel display according to a first embodiment of the present invention.

FIG. 2 is a schematic partial cross-sectional view taken along the line XX ′ of FIG. 1;

FIG. 3 is a schematic partial cross-sectional view of a flat panel display according to a second embodiment of the present invention.

FIG. 4 is a schematic partial sectional view of a flat panel display according to a third embodiment of the present invention.

FIG. 5 is a schematic partial sectional view of a flat panel display according to a fourth embodiment of the present invention.

FIG. 6 is a schematic plan view of a conventional flat panel display.

FIG. 7 is a schematic sectional view taken along the line Y-Y 'in FIG.

[Explanation of symbols]

10, 30, 40, 50, 60 Flat panel display 11, 31, 41, 51, 61 Glass panel 11a, 31a, 41a, 51a, 61a A surface 11b, 31b, 41b, 51b, 61b B surface 12, 32, 42 , 52, 62 Light-emitting device 13, 33, 43, 53 Groove 34 Metal film 45, 56 Second glass panel

Continued on the front page F term (reference) 5C094 AA05 AA09 AA16 AA36 AA47 AA49 BA25 CA18 DA20 DB01 EB02 ED01 ED11 ED15 FA02 FA04 FB02 GB10 JA01 JA08 JA13

Claims (12)

[Claims] 1. A flat panel display comprising: a glass panel; and a plurality of light emitting elements arranged in a matrix on one surface of the glass panel, wherein the surface of the glass panel on which the light emitting elements are arranged. A groove having a width equal to or less than the gap between the adjacent light emitting elements is formed at a depth equal to or more than two-thirds of the thickness of the glass panel from the opposite surface toward the gap between the adjacent light emitting elements. A flat panel display formed on the glass panel. 2. The flat panel display according to claim 1, wherein a second glass panel is attached to a surface of the glass panel where the groove is formed. 3. The flat panel display according to claim 1, wherein the width of the light emitting element is 100 μm or less. 4. The width of the groove is w2, the width of the light emitting element is w1, the pitch of the light emitting element is p, the thickness of the glass panel is t1, the refractive index of glass is n1, and the refractive index of air is n2.
Where d2 = t1- {0.5 × (p−w1 + w2)} × tan
The flat panel display according to claim 1 or 2, wherein the ^{value is} {sin ^-1 (n2 / n1)} or more. 5. The flat panel display according to claim 1, wherein a surface of the glass panel in contact with the groove is mirror-finished. 6. The flat panel display according to claim 1, wherein a metal film is formed on a surface of the glass panel in contact with the groove. 7. The flat panel display according to claim 1, wherein a light absorbing film is formed on a surface of the glass panel in contact with the groove. 8. A glass panel composed of two layers of a first glass panel and a second glass panel joined to each other, and a plurality of light emitting elements arranged in a matrix on a non-joining surface of the second glass panel. A flat panel display comprising: a light-emitting element between adjacent light-emitting elements corresponding to a gap between the light-emitting elements formed on the second glass panel from a bonding surface of the first glass panel. The groove having a width equal to or less than the gap has a depth equal to or more than twice the thickness of the second glass panel, and
A flat panel display characterized by being formed on a glass panel. 9. The flat panel display according to claim 8, wherein the width of the light emitting element is 100 μm or less. 10. The flat panel display according to claim 8, wherein a surface of the glass panel in contact with the groove is mirror-finished. 11. The flat panel display according to claim 8, wherein a metal film is formed on a surface of the glass panel in contact with the groove. 12. The flat panel display according to claim 8, wherein a light absorbing film is formed on a surface of the glass panel in contact with the groove.