JPH0625357B2 - Fluorescent high pressure mercury lamp - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a fluorescent high pressure mercury lamp with improved color rendering.

Structure of Conventional Example and Its Problems The fluorescent high-pressure mercury lamp is one of the typical high-pressure discharge lamps widely used for general lighting mainly for outdoor lighting due to its excellent life characteristics. The drawback of this lamp is that it has a low color rendering property, and the CIE has an average color rendering index Ra of about 43. In recent years, attempts have been made to improve the color rendering of fluorescent high pressure mercury lamps.
The Ra was improved to about 50 by adding a blue-green phosphor in addition to the conventional red phosphor.

However, even the fluorescent high-pressure mercury lamp having this improved color rendering property is still insufficient in terms of color rendering property for use for indoor lighting, and has not yet spread.
One of the reasons why the color rendering of conventional high pressure mercury lamps is not sufficiently improved is 405 nm emitted from the arc tube.
It was known that this is because the mercury emission line output at 436 nm was too strong. The output of the mercury emission line can be suppressed to some extent, for example, by forming a titanium oxide film, but it was considered unsuitable to simply suppress the emission line of the mercury because the efficiency of the lamp was lowered. . That is, in the conventional color rendering improved high-pressure mercury lamp, since the color rendering property is improved without suppressing the mercury emission line in the blue region, the improvement is not sufficient, and it is even more necessary for widespread use in indoor lighting. Was desired.

OBJECT OF THE INVENTION The present invention relates to a fluorescent high-pressure mercury lamp that suppresses the output of mercury emission lines in the blue region, and particularly to a fluorescent high-pressure mercury lamp whose color rendering property is significantly improved.

Structure of the invention The fluorescent high-pressure mercury lamp of the present invention is a high-pressure mercury lamp comprising a light-emitting tube that emits visible radiation and ultraviolet radiation, and a fluorescent coating film formed on the inner surface of the outer tube of the fluorescent tube. A first phosphor whose coating is trivalent cerium-activated yttrium aluminate, a second phosphor whose coating is divalent europium-activated strontium aluminate, and a trivalent europium-activated yttrium vanadate. And a third fluorescent substance which is at least one kind of trivalent europium-activated yttrium vanadate phosphate, and is a fluorescent high-pressure mercury lamp characterized by comprising: By absorbing the mercury emission line and simultaneously adding light emission to the blue-green range, the yellow-green range, and the red range, the color rendering properties have been greatly improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Description of Examples Example 1 75 wt% Y _0.95 VO ₄ : Eu _0.05 for red phosphor, 20 wt% Sr _3.88 Al ₁₄ O ₂₅ : Eu _0.12 for blue-green phosphor, 20 wt% for yellow-green phosphor. Y _2.9 Al ₅ O ₁₂ : Oe _0.1 was mixed at a ratio of 5% by weight, and then 5% by weight of erosile (SiO ₂ ) was added and mixed sufficiently, and then 2.0 mg /
It was electrostatically applied to a film thickness of cm ² . An arc tube was incorporated into this outer tube to obtain a 100 W high pressure mercury lamp. The luminous flux of the obtained lamp was 4660 m, the color temperature was 3660 K, and the average color rendering index Ra was 58, which was a clear improvement. This improvement is obtained by the synergistic effect of the luminescent component of the mixture of phosphors and the effect of absorbing light in the blue region possessed by the blue-green and yellow-green phosphors.

Conventionally, this yellow-green fluorescent substance (hereinafter, as a general formula, YAG: Ce
USPatent 4,034,257 shows an example of improving the color rendering by using a high-pressure mercury lamp together with a red phosphor, but its Ra is about 51, and only in combination with the red phosphor. Shows that the effect of improving the color rendering property is small. FIG. 1 shows the spectral reflectance curve (curve 1) of the blue-green phosphor and the spectral reflectance curve (curve 2) of the yellow-green phosphor used in this example. The spectral distribution of the 100 W fluorescent high pressure mercury lamp according to this example is shown in FIG.

Example 2 The same fluorescent substance as in Example 1 was applied to the inner surface of a 400 W outer tube in the same manner, and a 400 W fluorescent high pressure mercury lamp was produced in the same manner. The luminous flux of the obtained lamp is 24600 m and the color temperature is 3
The color rendering index Ra was 400K and the average color rendering index Ra was 56, which was clearly improved.

Example 3 85% by weight of Y _0.95 V _0.5 P _0.5 O ₄ : Eu _0.05 was _added to a red phosphor,
10% by weight of Sr _3.9 Al ₁₄ O ₂₅ : Eu _0.1 was mixed with the blue-green fluorescent substance, and 5% by weight of YAG: Ce was mixed with the yellow-green fluorescent substance, and 10% by weight of erogel (SiO ₂ ) was added thereto. After addition and thorough mixing, electrostatic coating was applied to the outer tube of a 100 W high pressure mercury lamp at a film thickness of 3 mg / cm ² . The luminous flux of the obtained lamp is 4440.
m, color temperature 3450K, average color rendering index Ra was 60.

Example 4 70% by weight of Y _0.95 VO ₄ : Eu _0.05 for a red fluorescent substance, 25% by weight of Sr _3.8 Al ₁₄ O ₂₅ : Eu _0.2 for a blue-green fluorescent substance, and YAG: Ce for a yellow-green fluorescent substance. After mixing at a ratio of 5% by weight, 5% by weight of erogel (SiO ₂ ) was added and mixed well, and then 1
Electrostatic coating was applied to the inner surface of the outer tube of the 00 W high-pressure mercury lamp to a film thickness of ² mg / cm ² . The luminous flux of the obtained lamp is 4650.
m, color temperature 3720 K, and average color rendering index Ra was 60.

EFFECTS OF THE INVENTION As described above, the present invention relates to a fluorescent high-pressure mercury lamp with greatly improved color rendering properties, and the phosphor coating is a trivalent cerium-activated yttrium aluminate phosphor. Fluorophores, divalent europium-activated strontium aluminate fluorescers, second luminophores, trivalent europium-activated yttrium vanadate and trivalent europium-activated yttrium vanadate phosphate fluors And a third fluorescent body, which is at least one kind of luminous body, to suppress the output of the mercury emission line in the blue region emitted from the arc tube, and to suppress the red, blue-green and yellow-green regions. It is possible to provide a fluorescent high-pressure mercury lamp whose color rendering property is significantly improved by adding light emission from a fluorescent substance to.

[Brief description of drawings]

FIG. 1 shows the first fluorescent substance and the second fluorescent substance described in the claims.
FIG. 2 is a diagram showing the spectral reflectance curve of the phosphor of FIG. 2, and FIG. 2 is a diagram showing the spectral distribution of the 100 W fluorescent high pressure mercury lamp of the present invention.

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Claims (1)

[Claims] 1. A high-pressure mercury lamp comprising an arc tube that emits visible radiation and ultraviolet radiation, an outer tube that surrounds the arc tube, and a phosphor coating that is formed on the inner surface of the outer tube. The first phosphor, whose phosphor coating is a trivalent cerium-activated yttrium aluminate phosphor, and the second phosphor, which is a divalent europium-activated strontium aluminate phosphor, A third phosphor, which is at least one of a phosphor and a trivalent europium-activated yttrium vanadate phosphor and a trivalent europium-activated yttrium vanadate phosphate phosphor. A fluorescent high-pressure mercury lamp characterized by comprising a body.