JPH01231260A - Fluorescent lamp - Google Patents

Abstract

PURPOSE:To reduce a change with the passage of time of the optical output for securing a long life by providing two mutually opposing parts, to which no phosphor is applied, on the inside of a glass tube and arranging conductors on the glass tube outside of these parts respectively. CONSTITUTION:Gas 2 such as rare gas and mercury vapor are sealed in the inside of a glass tube 1 and a phosphor 3 is applied to the inside of the glass tube 1. However, the phosphor 3 arranges the opening parts (the parts having no phosphor 3) 9a and 9b in the tube axis direction in the two diametrically opposing places on the glass tube inside and the respective conductors 4a and 4b are arranged on the outside of the glass tube 1 of these respective opening parts 9a and 9b. Accordingly, the phosphor 3 does not exist in the parts of the conductors 4a and 4b receiving a shock of electrons and ions so that there is no danger of generating remarkable deterioration of the phosphor due to the shock of electrons and ions. Thereby, a change with the passage of time due to deterioration of an optical output is little so that a long life can be secured.

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention provides a method for discharging electrical discharge materials such as rare scum or metal vapor.
The present invention relates to a fluorescent lamp that is enclosed in a glass container (bulb) whose inner surface is coated with fluorescent substance 7T, and a conductor is provided on the outer surface of the container.

[Conventional technology]

Fluorescent material on the inside? A discharge material such as a rare gas or metal vapor is sealed in a glass tube coated with 'T, and a high frequency voltage is applied to the conductor arranged on the outer surface of the glass tube to discharge the gas inside the tube. Figures 3 and 4 show an example of a conventional fluorescent lamp of this type, which converts the generated ultraviolet rays into the required light using a fluorescent material.
1 shows a vertical cross-sectional plan view and an enlarged cross-sectional view of a fluorescent lamp disclosed in Japanese Patent No. 0-12660, respectively.

In both countries, the inside of the container glass tube 1 is filled with mercury vapor and rare gas 2, and the inner surface of the glass tube 1 is filled with phosphor 3.
It is applied completely in the axial direction. 4a and 4b are a pair of conductors arranged on the outer surface of the glass tube 1 to face each other in the diametrical direction. 5 is a plug for connecting to a power source, 6
is a switch, and 7 is a high frequency power supply.

Finally, the operation of the above configuration will be explained.

When power is applied from the plug 5 and the switch 6 is turned on, a high frequency '1π source 7 generates a high frequency, which is applied to the conductors 4a and 4b, and a discharge 8 is generated. This discharge 8 excites mercury atoms to generate ultraviolet rays, which causes the phosphor 3 to emit light.

In such fluorescent lamps, there is no electrode such as a filament inside the glass bulb, so there is no blackening at the end.
You can expect a long life. In addition, such fluorescent lamps are
To prevent noise generation, it is necessary to use a high frequency of 20k11□ or higher, but 525k112 or higher is inappropriate because it is in the radio AM frequency band and becomes a source of noise.

[Problem to be solved by the invention]

Since the conventional fluorescent lamp was constructed as described above, when the conductors 4a and 4b are bombarded by electrons and ions, the phosphor 3 inside the glass tube in these parts is exposed to other parts during use. There is a problem in that the optical output deteriorates more rapidly than the other parts, leading to deterioration of the optical output and causing a change in the overall optical output over time. Particularly in applications such as optical information equipment such as facsimiles, where the optical output changes over time, the lifespan is short.

This invention was made in order to solve the problems of the conventional examples as described above, and aims to provide a fluorescent lamp of this type that has a long life and has little deterioration in light output over time. .

[Means to solve the problem]

For this reason, in the fluorescent lamp according to the present invention, a plurality of portions where two phosphors are not present are provided on the inner surface of the glass bulb, and each conductor is provided on the outer surface of the glass bulb in each portion. The purpose of the present invention is to achieve the above object by configuring the system to provide the following information.

[Function] In the fluorescent lamp according to the present invention having the above-described structure, since there is no phosphor in the part of the conductor that receives Iff from electrons and ions, the phosphor is not affected by the impact of electrons and ions as in the conventional example. Since there is no risk of significant deterioration, there is little change in optical output over time due to deterioration, and a long life is ensured.

(Examples) The present invention will be described below based on Examples. FIG. 1 shows a cross-sectional side view of an embodiment of this type of fluorescent lamp according to the present invention, and the same (equivalent) components as in FIG. 4, which is a corresponding diagram of the conventional example, are designated by the same reference numerals.

(Structure) In FIG. 1, a glass tube (or bulb) 1 is filled with a discharge material 2 such as dilute scum or mercury vapor. The inner surface of the glass tube 1 is coated with a phosphor 3, and the phosphor 3 has openings in the tube axis direction (portions where the phosphor 3 does not exist) 9a at two diametrically opposed locations on the inner surface of the glass tube.
9b, and conductors 4a, 4b are provided on the outer surface of the glass tube 1 in the first portions 9a, 9b.

(Function) Each conductor 4a, 4. On the inner surface of the glass tube 1 in b, a high electrode drop voltage is generated due to ionization to sustain the discharge, and electrons and ions accelerated by this voltage collide. However, since this part is between each part 9a and 9b where the phosphor 3 does not exist, the phosphor 3 is directly affected by this collision.
I have never received one. Therefore, the fear of rapid deterioration of the phosphor 3 due to bombardment with electrons and ions is eliminated.

Note that in the above embodiment, each conductor 4a.

By forming 4b from a high reflectance material and reflecting the light from each opening 9a, 9b of the phosphor 3, the light can be further utilized for action, resulting in high efficiency.

(Other Embodiments) Fig. 2 shows a vertical cross-sectional front view of another embodiment of the present invention, and the same (equivalent) components as in Fig. 1.3.4 are represented by the same or equivalent symbols. .

In this embodiment, the phosphor 3 is coated on the inner surface of the glass tube 1 except for the opposite ends 9c and 9d, which face each other in the tube axis direction. 9
A pair of conductors 4c and 4d are arranged on the outer surface of the glass tube d.

In this embodiment as well, as in the first embodiment, a high frequency wave is applied from the high frequency power supply 7 to the conductors 4c and 4d, thereby generating a discharge between the conductors 4c and 4d. A high electrode drop voltage is generated on the inner surfaces of the conductors 4c and 4d to maintain the discharge, and either the 'lu molecules and ions accelerated by this voltage collide with the inner surface of the bulb, or there is a phosphor present in these parts. Therefore, severe deterioration cannot occur due to this.

On the other hand, apply phosphor 3! 5 becomes a positive column with a low potential gradient, the impact of electrons and ions is small, and the deterioration of the phosphor 3 due to this is small. In addition, since the sunlight column is not shielded by the side surface or the conductive body, the luminous efficiency is high.

In this second example bh, the guide bodies 4c, 4 are arranged so as to cover only the side surfaces of both ends of the glass tube 1.
d is provided, but it goes without saying that each end face of the glass tube 1 that is perpendicular to +1 in the tube axis direction may also be covered.

(Effects of the Invention) As explained in 1-1, according to the present invention, two uncoated portions of phosphor facing lf are provided on the inner surface of the glass tube, and the glass of this portion is On the outer surface of the tube - f
- Since the structure is configured so that a conductor is provided, the phosphor is not subjected to direct impact from '1πf or ions,
This type of fluorescent lamp has a long lifespan with little change in light output over time due to less deterioration of the phosphor.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of a fluorescent lamp according to the present invention.
1 - sectional side view, FIG. 2 is a vertical cross-sectional view of another embodiment, FIG. 3 is a vertical cross-sectional view of a conventional fluorescent lamp, and FIG. 4 is an enlarged cross-sectional view of FIG. 3. It is a front view. 1... Glass tube (bulb) 2... Electric discharge body 3... Fluorescent substance 7... High frequency electromagnetic radiation Note that the same symbols in each figure are the same. or indicate an equivalent component.

Claims (1)

[Claims] A fluorescent lamp having a phosphor layer on the inner surface of a glass bulb, a pair of conductors arranged on the outer surface, and configured to discharge a discharge body in the bulb by applying a high frequency voltage to each conductor. A fluorescent lamp characterized in that two mutually opposing portions where no phosphor is present are disposed on the inner surface of the bulb, and each of the conductors is disposed on the outer surface of the glass bulb in each portion. .