JPH08306341A - Fluorescent lamp - Google Patents

Abstract

PURPOSE: To provide a fluorescent lamp having high light emitting efficiency without being affected by the ambient temperature. CONSTITUTION: A first phosphor layer 2a which converts vacuum ultraviolet rays emitted from xenon plasma 3b into far ultraviolet rays or near ultraviolet rays and a second phosphor layer 2b which converts far ultraviolet rays or near ultraviolet rays into visible light rays are formed on an inner wall face of a light transmissive bulb 1 in which xenon is sealed. Consequently, a fluorescent lamp having high light emitting efficiency without being affected by ambient temperature can be obtained.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to fluorescent lamps.

[0002]

2. Description of the Related Art FIG. 3 is a conceptual diagram showing a light emitting action of a first conventional example according to the present invention.

A conventional fluorescent lamp has a phosphor layer 2 on the inner wall surface.
A discharge gas (argon gas and mercury) is enclosed in the light-transmitting bulb 1 coated with, and ultraviolet rays are emitted from the mercury by the discharge 3a, and the phosphor layer 2 is excited and emits light. Have.

[0004]

However, the mercury contained in the bulb of the fluorescent lamp of the first conventional example is:
The first problem arises that the light emission characteristics of the fluorescent lamp change depending on the ambient temperature because the ambient temperature is easily affected.

As a solution to this problem, there is a xenon lamp in which mercury is not enclosed inside the bulb.
(Second Conventional Example) However, in the second conventional example, the following second problem occurs.

In many conventional phosphors used in fluorescent lamps, when visible radiation is obtained by using an ultraviolet wavelength as an excitation source, it includes 254 nm emitted by a low-pressure mercury discharge,
Excitation sensitivity in the far-ultraviolet to near-ultraviolet wavelength region of 200 to 380 nm is relatively high, but it is emitted from a xenon discharge.
Since the excitation sensitivity in the vacuum ultraviolet region such as 7 nm is generally low, the xenon lamp shown in the second conventional example has a low luminous efficiency.

The present invention has been made in view of all the above problems, and an object of the present invention is to provide a fluorescent lamp having high luminous efficiency without being affected by ambient temperature.

[0008]

In order to solve the above problems, according to the invention of claim 1, xenon is enclosed in the light-transmitting bulb, and the phosphor is provided on the inner wall surface of the light-transmitting bulb. In a fluorescent lamp in which a layer is formed, the phosphor layer is a first phosphor that converts vacuum ultraviolet light from xenon into far ultraviolet light or near ultraviolet light, and far ultraviolet light or near ultraviolet light is visible light. And a second phosphor that is converted into

According to the second aspect of the present invention, the phosphor layer is formed by applying the second phosphor as the first layer on the inner wall surface of the translucent bulb and by using the second phosphor as the second layer. It is characterized in that it has a two-layer structure coated on the second phosphor.

According to a third aspect of the invention, the phosphor layer has a single-layer structure made of a mixture of the first phosphor and the second phosphor.

According to the invention of claim 4, the first phosphor is BaSi ₂ O ₅ : Pb or (CaZn).
₃ (PO ₄ ) ₂ : Tl, and the second phosphor is (BaCaMg) ₁₀ (P
O ₄ ) ₆ Cl ₂ : Eu, Y ₂ SiO ₅ : Ce. Tb, Y
It is characterized in that it is composed of at least one of (PV) O ₄ : Eu.

[0012]

According to the present invention, the first phosphor is excited by the vacuum ultraviolet light from xenon to emit far-ultraviolet to near-ultraviolet light, and the first ultraviolet phosphor emits far-ultraviolet to near-ultraviolet light. The second phosphor is excited to emit visible light.

[0013]

【Example】

(Embodiment 1) FIG. 1 is a conceptual diagram showing the light emitting action of the first embodiment according to the present invention.

The difference from the first conventional example shown in FIG. 3 is that instead of the phosphor layer 2, the first phosphor layer 4a made of the phosphor BaSi ₂ O ₅ : Pb and the phosphor (BaCaMg) _{10 are used.}
(PO ₄ ) ₆ Cl ₂ : Eu, Y ₂ SiO ₅ : Ce. T
The second phosphor layer 4b made of a mixture of b, Y (PV) O ₄ : Eu is provided, and xenon is used as the discharge gas in the bulb to generate the xenon discharge plasma 3b. The same configurations as those of the first conventional example are denoted by the same reference numerals and the description thereof will be omitted.

Here, the phosphor layer 2a is vacuum ultraviolet light (mainly 147 nm) emitted from the xenon discharge plasma 3b.
And emits near-ultraviolet light having a peak wavelength of about 351 nm to the phosphor layer 2b.

The phosphor layer 2b has a peak wavelength of about 351n.
(BaCaMg) ₁₀ (P
O ₄ ) ₆ Cl ₂ : Eu (peak wavelength 483 nm), Y ₂
SiO ₅ : Ce. Tb (peak wavelength 543 nm), Y
It emits visible light of (PV) O ₄ : Eu (peak wavelength 620 nm). By adjusting the mixing ratio of these three types of phosphors, white light can be obtained as a whole, and the efficiency of use of ultraviolet rays (emission efficiency) is improved as compared to the xenon lamp as shown in the second conventional example without using mercury. It is possible to

The phosphor layers 2a and 2b may be any phosphor as long as the phosphor layer 2b has an excitation spectrum that has a large overlap with the emission spectrum of the phosphor layer 2a. May be used.

(Embodiment 2) FIG. 2 is a conceptual diagram showing the light emitting action of the second embodiment according to the present invention.

The difference from the first embodiment shown in FIG. 1 is that (CaZn) ₃ is used instead of the phosphor layers 2a and 2b.
(PO ₄ ) ₂ : Tl, Y ₂ SiO ₅ : Ce. The phosphor layer 5 made of a mixture of Tb (peak wavelength 543 nm) is provided, and the same configurations as those of the other first embodiment are denoted by the same reference numerals and the description thereof will be omitted.

In the phosphor layer 2c, the vacuum ultraviolet light emitted from the xenon discharge plasma 3b is first converted into near-ultraviolet light having a peak wavelength of 306 nm by the phosphor (CaZn) ₃ (PO ₄ ) ₂ : Tl. , And then the near-ultraviolet light having a peak wavelength of 306 nm, the phosphor Y ₂ SiO ₅ : Ce.
By Tb, it is converted into visible light having a peak value of 543 nm, and green visible light is obtained. The phosphor layer 2c is
Any phosphor may be used as long as it satisfies the required characteristics.

[0021]

According to the present invention, it is possible to provide a fluorescent lamp which has a high luminous efficiency without being affected by the ambient temperature.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a light emitting action of a first embodiment according to the present invention.

FIG. 2 is a conceptual diagram showing a light emitting action of a second embodiment according to the present invention.

FIG. 3 is a conceptual diagram showing a light emitting action of a first conventional example according to the present invention.

[Explanation of symbols]

 1 Translucent bulb 2 Phosphor layer 3 Discharge

Claims (4)

[Claims] 1. A fluorescent lamp in which xenon is enclosed in a translucent bulb and a phosphor layer is formed on an inner wall surface of the translucent bulb, wherein the phosphor layer is a vacuum from the xenon. A fluorescent lamp comprising a first phosphor that converts ultraviolet light into far-ultraviolet light or near-ultraviolet light, and a second phosphor that converts the far-ultraviolet light or near-ultraviolet light into visible light. . 2. The phosphor layer is formed by applying the second phosphor as a first layer on the inner wall surface of the translucent bulb, and by using the second phosphor as a second layer in the second phosphor. The fluorescent lamp according to claim 1, which has a two-layer structure applied on the body. 3. The fluorescent lamp according to claim 1, wherein the phosphor layer has a single-layer structure made of a mixture of the first phosphor and the second phosphor. 4. The first phosphor is BaSi ₂ O ₅ :
At least one of Pb or (CaZn) ₃ (PO 4) ₂ : Tl is used, and the second phosphor is (BaCaMg) ₁₀ (PO ₄ ) ₆
Cl ₂ : Eu, Y ₂ SiO ₅ : Ce. Tb, Y (PV)
O _4: Fluorescent lamp according to any one of claims 1 to 3, characterized in that it is made of at least one of Eu.