JP3238946B2 - Flat fluorescent lamp - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat fluorescent lamp suitable for a backlight of a liquid crystal panel used for a liquid crystal TV or a liquid crystal projector.

[0002]

2. Description of the Related Art Conventionally, as this type of flat fluorescent lamp, there is one disclosed in, for example, JP-A-63-10458.

FIG. 2 is a sectional view of a main part of a conventional flat fluorescent lamp.

In the figure, 1 is a front glass, 2 is a rear glass,
3a is an upper portion of the frame glass, 3b is a lower portion of the frame glass, and these form a flat glass container.

In this glass container, a linear cathode 5 supported by a plurality of columns 4, mesh electrodes 6a and 6b as grid electrodes, a fluorescent film 7 formed on the inner surface of the front glass, and the fluorescent film An anode 8 of a metal back formed by vapor deposition of aluminum is disposed on the film 7.
A high-pressure supply unit 9 is disposed at an end of the unit via a carbon paste or the like. The energy of the electrons from the linear cathode 5 passes through the anode 8 to excite the fluorescent film 7 to emit light with high brightness. At this time, light emitted from the fluorescent film 7 toward the rear panel is reflected by the metal back and emitted toward the front panel.

A plate-like spacer glass 10 having a predetermined width is sandwiched between the upper and lower portions 3a and 3b of the frame glass, and the mesh electrodes 6a and 6b are attached to both surfaces thereof. . The spacer glass 10 is interposed between the column 4 and the high-pressure supply unit 9 and in a portion other than the effective light emitting unit,
The discharge between the two is prevented.

A back electrode 11 is provided on the inner surface of the back glass 2. This back electrode 11 is for making the emission of electrons from the linear cathode 5 uniform. That is, since the electrons are also emitted from the lower part of the linear cathode 5 due to the presence of the back electrode 11, the mesh electrode 6a,
Since the projections 6b are evenly projected on the fluorescent film 6b, they also hit the fluorescent film 7 uniformly, and the brightness is made uniform.

The voltage of each of the electrodes is set, for example, by setting the linear cathode 5 to a 6V (100 KHz) mesh electrode 6a, 6K.
It is preferable that b is set to 15 V and 200 V, the anode 8 is set to 10 KV, and the back electrode 11 is set to 10 V.

On the outer surface of the front glass 1, a multilayer interference film 12 is formed. The multilayer interference film 12 is formed by alternately laminating a plurality of thin films having a high refractive index and thin films having a low refractive index. For example, TiO ₂ and SiO ₂ are alternately deposited in multiple phases. As shown in FIG. 3, the transmittance characteristic with respect to the incident angle of light is, for example, in the case of green light of wavelength λ = 544 nm, the incident angle is 32 ° with respect to the normal line of the multilayer interference film 12
Is set so that the transmittance becomes 0.5.

Therefore, of the light emitted from the fluorescent film 7, those having a small angle with respect to the normal line are transmitted, but those having a large angle are not transmitted but are reflected inside, and are again reflected in the fluorescent film 7. Are emitted at an angle different from that described above, a part of which is transmitted at a small angle with respect to the normal, and the other is reflected. By repeating this process, the light component having a small angle with respect to the normal increases greatly. Therefore, the light emitted from the front glass 1 of the flat fluorescent lamp is almost parallel light.

Further, since the multilayer interference film 12 is formed on the outer surface of the front glass 1, light emitted from the fluorescent film 7 and reflected inside by the multilayer interference film 12, as shown in FIG. The light attenuates as it passes through the glass 1 over several degrees. For this reason, although the light intensity is slightly reduced, the deterioration of the multilayer interference film 12 due to the electron beam is prevented.

In the flat fluorescent lamp having such a multilayer interference film formed thereon, before assembling the components such as the front glass, the rear glass, the frame glass, and the electrodes, the multilayer interference film and the fluorescent film are formed on the outer surface of the front panel in advance. It is necessary to form an optical film. For this reason, in such a manufacturing process, even if a multilayer interference film is formed on the front glass satisfactorily, if a defective product is formed in a later assembly process, the formation of the multilayer interference film in the previous process is useless. Disadvantage.

[0013]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks of the prior art, and a flat type fluorescent film in which a multilayer interference film is not wasted even when a defective product is formed in an assembling process. It is intended to provide a lamp.

[0014]

A flat fluorescent lamp according to the present invention has a fluorescent lamp body having a front glass on the outermost surface from which light is emitted from the inside and a multilayer interference film formed on a glass panel. A multilayer interference filter, wherein the multilayer interference filter is bonded and fixed to the outer surface of the front glass with a transparent adhesive.

[0015]

According to the above construction, after the fluorescent lamp main body is formed, the multilayer interference filter can be joined only to the non-defective fluorescent lamp main body. Waste can be prevented.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view of a main part of a flat fluorescent lamp according to the present embodiment. The same parts as those in FIG. 2 are denoted by the same reference numerals, and the description thereof is omitted.

A multilayer interference filter 13 is bonded and fixed to the outer surface of the front glass 1 with a transparent adhesive 14 such as a transparent silicone adhesive.

The multilayer interference filter 13 is formed by forming a multilayer interference film 12 on the upper surface of a transparent plate-shaped glass panel 15 by a film forming process such as vapor deposition. It serves as a bonding surface and is in contact with the front glass 1 via an adhesive 14. Therefore, the glass panel 15 is located on the opposite side to the front glass 1, that is, on the outside. The multilayer interference film 12 has the same configuration as that described in the conventional example of FIG. 2 and performs the same function.

In the flat fluorescent lamp having such a structure,
A multilayer interference film is formed in advance on a large substrate to be a glass panel by a film forming process, and the substrate is cut into necessary dimensions to form a multilayer interference filter 13. On the other hand, separately from the front glass 1, the back glass 2, the frame glasses 3a and 3b, the support 4, the linear cathode 5, the mesh electrodes 6a and 6b, the high-voltage supply unit on which the fluorescent film 7 and the anode 8 are formed in advance 9. Assemble the spacer glass 10 and the like to form the fluorescent lamp body 16. Then, the multi-layer interference filter 13 formed in advance is bonded and fixed to the outer surface of the front glass 1 of the fluorescent lamp main body 16 formed by the above steps with a transparent adhesive material 14, so that the flat fluorescent lamp is manufactured. Complete.

In the flat fluorescent lamp of the present embodiment as described above, if a defective product is formed when the fluorescent lamp body 16 is manufactured, the multilayer interference filter 13 is bonded and fixed to the defective product. And the multi-layer interference film can be used efficiently, leading to cost reduction.

In the above embodiment, the fluorescent lamp main body is configured to emit light by the fluorescent film. However, in the present invention, the configuration of the fluorescent lamp main body is not limited to the configuration of the above embodiment.

[0023]

According to the present invention, it is possible to prevent the multilayer interference film from being wasted due to a defective fluorescent lamp main body, and to provide a flat fluorescent lamp suitable for cost reduction.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a flat fluorescent lamp according to the present invention.

FIG. 2 is a sectional view of a main part of a conventional flat fluorescent lamp.

FIG. 3 is a characteristic diagram of a multilayer interference film.

FIG. 4 is a cross-sectional view showing a light transmitting state.

[Description of sign]

 DESCRIPTION OF SYMBOLS 1 Front glass 12 Multilayer interference film 13 Multilayer interference filter 14 Adhesive material 15 Glass panel 16 Fluorescent lamp main body

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01J 61/40 G02B 5/28 H01J 61/30

Claims (1)

(57) [Claims] 1. A fluorescent lamp body having a front glass on the outermost surface from which light is emitted from the inside, and a multilayer interference filter having a multilayer interference film formed on a glass panel. A flat fluorescent lamp comprising the multilayer interference filter bonded and fixed with a transparent adhesive.