JP2001185082A - Fluorescent lamp having light accumulation function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a fluorescent lamp having a light accumulation function that reduces the used amount of light accumulation phosphor and general phosphor. SOLUTION: In daybreak or early evening, by noticing a light emission peak of the optimum light accumulation phosphor, under this condition, a fluorescent lamp having the light accumulation function having the light accumulation phosphor of the light emission peak of 510-530 nm has the best visibility. As a result, at one lamp, the used amount of the light accumulation phosphor and the used amount of general phosphor such as three-wavelength mixed phosphor or the like can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent lamp having a luminous function, in which the amount of luminous phosphor and ordinary phosphor used is reduced.

[0002]

2. Description of the Related Art A fluorescent lamp with a light storage function in which a light storage phosphor is provided between a glass bulb (lamp tube) and a normal phosphor layer,
It has already been put to practical use and uses a phosphorescent phosphor (manufactured by Nichia Corporation) having a composition of Sr ₄ Al ₁₄ O ₂₅ : Eu, Dy having an emission peak near 490 nm.

FIG. 7 shows an example of a sectional structure of a fluorescent lamp having a light storage function and the principle of light emission. During the operation of the lamp, as shown in (a), a normal phosphor such as a three-wavelength mixed phosphor converts ultraviolet light generated by the discharge of the lamp into visible light. Most of the converted visible light passes through the glass bulb 1 and is radiated to the outside of the lamp, but part of the converted visible light is not radiated to the outside of the lamp, but is usually stored between the phosphor and the glass. It is stored in the phosphor or reflected by the phosphorescent phosphor, and usually returns to the phosphor layer 3 or the discharge space. Therefore, as the amount of phosphor used per lamp is increased and the phosphor layer 2 is made thicker, the brightness of the fluorescent lamp during lighting decreases. On the other hand, when the lamp is turned off, as shown in (b), only the light of the phosphorescent stored in the phosphorescent phosphor is emitted to the outer surface of the lamp.
The intensity of the phosphorescent light is proportional to the amount of phosphorescent phosphor used per lamp. For this reason, in order not to significantly reduce the light emission of the normal phosphor at the time of lighting and to maintain the light intensity of the light storage at the time of turning off the light to a practical level, it is necessary to use the phosphorescent phosphor and the normal phosphor per lamp. You have to use more. Rare earth phosphors used in three-wavelength fluorescent lamps are expensive, and phosphorescent phosphors used in fluorescent lamps with a light storage function are twice or three times as expensive. Therefore, increasing the amount of these phosphors leads to a significant cost increase.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a fluorescent lamp with a light storing function, in which the amount of the light storing phosphor and the normal phosphor is reduced.

[0005]

A fluorescent lamp with a light storage function according to the present invention is a fluorescent lamp with a light storage function comprising two phosphor layers, a phosphor layer and a phosphor layer for exciting the phosphor layer. The emission peak wavelength of the phosphorescent phosphor is 51.
It is characterized by having a thickness of 0 to 530 nm.

The phosphorescent phosphor layer is applied to the non-discharge side of the lamp tube of the fluorescent lamp, and the phosphor layer for exciting the phosphorescent phosphor layer is applied to the discharge side of the lamp tube of the fluorescent lamp. Features.

[0007] The phosphorescent phosphor layer is a layer in which a phosphorescent phosphor is impregnated in a resin tube coated on the outer surface of a lamp tube of a fluorescent lamp, and the phosphor layer for exciting the phosphorescent phosphor layer is a lamp of the fluorescent lamp. It is characterized in that it is applied to the inner surface of the tube.

The phosphorescent phosphor is dysprosium, europium-activated strontium aluminate or dysprosium, europium-activated strontium boroaluminate.

The phosphor layer that excites the phosphorescent phosphor includes a red phosphor having an emission peak around 610 nm, a green phosphor having an emission peak around 545 nm, and a blue phosphor having an emission peak around 450 nm. A mixture of at least any two of the phosphors.

[0010] The resin tube is provided with the phosphorescent phosphor for three times.
% To 5%.

[0011] The fluorescent lamp with a light storage function reduces the amount of phosphor in the phosphor layer that excites the phosphorescent layer, as compared with a fluorescent lamp with a light storage function in which the light emission phosphor has a light emission peak wavelength near 490 nm. It is characterized by a 20% reduction.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to "3.4 Brightness and Adaptation" in Chapter 3 "Light and Vision" (page 42) of the Lighting Handbook (edited by The Illuminating Engineering Society of Japan, Ohmsha) (p. 42). The range of illuminance can be broadly classified into the following three. (1) Photopic: The color and shape of an object are clearly understood. (2) Mesopic: you can see some color and shape of things. (3) Scotopic vision: Only light and dark can be seen while being blurred. The relationship between these three classifications and the illuminance is shown in FIG. 1 (see FIG. 3 in “3.4 Brightness and Adaptation” of Chapter 3 “Light and Vision” in the Writing Handbook (Illustration Society of Japan, Ohmsha)) (page 42).
・ Quote 27). As can be seen from this figure, the human eye works in a wide range of illuminances from starlight to direct sunlight. This is because the cells work. In mesopic vision, the appearance of objects is complex because the contributions of the can and pan systems change with the illuminance level.

The light stored in the conventional fluorescent lamp with a light storage function is designed so that the effect can be obtained in scotopic vision. That is, as shown by the solid lines in FIG. 2 (quoted from FIG. 1 in the 1996 Illumination Institute of Japan National Convention “17. A phosphorescent luminous body having an emission peak near 490 nm, which is close to the peak (around 507 nm) of the scotopic luminosity curve, is used. However, immediately after the fluorescent lamp with the luminous function is turned off or immediately after the lamp is turned off, it takes several minutes to
In a few minutes (for example, a time for searching for a flashlight or a candle due to a power outage or the like), that is, under the condition of mesopic vision in which the luminous intensity of the fluorescent lamp with the luminous function remains sufficiently, As described above, the function of the human eye is complicated, and the standard relative luminous efficiency curve for mesopic vision is not set.

The present inventors have focused on the optimum emission peak wavelength of the phosphorescent phosphor in mesopic vision, and under this condition, a phosphor with a phosphorescent function having a phosphorescent phosphor having an emission peak wavelength of 510 to 530 nm. It has been found that the lamp has the highest visibility, and as a result, the amount of the phosphor used per lamp and the amount of the usual phosphor such as the three-wavelength mixed phosphor can be reduced.

Embodiment 1 (1) Phosphor synthesis wavelengths 490 nm, 500 nm, 510 nm, 520 n
The phosphorescent phosphors having emission peaks at m, 530 nm, 540 nm, and 550 nm were synthesized as follows. SrCO ₃ , Al ₂ O ₃ , Eu ₂ O ₃ , Dy ₂ O ₃
After mixing each raw material in a ceramic pot containing a flux and alumina balls, rotating and mixing for 3 hours, the mixture was placed in an alumina crucible, and a reducing atmosphere in which a mixed gas of nitrogen and hydrogen was flown in an electric furnace. After firing at 1300 ° C for 3 hours,
This fired product was pulverized and passed through a 200-mesh sieve to obtain a phosphorescent phosphor. Preferred phosphorescent phosphors are, for example, dysprosium and europium activated strontium aluminate or dysprosium and europium activated strontium boroaluminate. SrCO ₃ , Al ₂ O ₃ , Eu
Phosphors having different emission peak wavelengths from 490 nm to 540 nm were obtained by changing the mixing ratio of each of the raw materials ₂ O ₃ and Dy ₂ O ₃ .

(2) Evaluation of the brightness perceived by the eyes of the light accumulation from scotopic vision to mesopic vision A polyethylene terephthalate resin film having a thickness of 0.1 mm is provided with 490 nm, 500 nm, 510 nm, and 520 nm.
m, 530 nm, 540 nm, and 550 nm, each of which is impregnated with 5% (weight% based on the resin tube, the same applies hereinafter) of seven types of phosphorescent phosphors having emission peaks at 530 nm, as phosphors for exciting the phosphorescent phosphor. 613n
Red, green, and blue mixed phosphors having emission peaks at m, 543 nm, and 450 nm, respectively (hereinafter, three-wavelength mixed phosphor)
Was applied to a circular fluorescent lamp FCL30 / 28 coated with FIG. 3 shows a sectional structure diagram and a light emission principle of these fluorescent lamps having a light storage function. The difference between FIG. 3 and FIG. 7 is that there is a resin tube impregnated with a phosphorescent phosphor serving as the phosphorescent phosphor layer 2 outside the glass bulb 1, and the principle of light emission is the same as that of FIG. The phosphorescent phosphor layer 2 may be formed by directly applying the phosphorescent phosphor to the outer surface of the lamp tube without using the resin tube. The light color of each fluorescent lamp was adjusted to EX-D color (color temperature 6700K).

The seven kinds of fluorescent lamps having a light storing function thus prepared were turned on for 15 minutes, and the illuminance conditions after turning off the light were changed, and a sensory test of recognition of characters drawn on a white plate by the light of the light storing was performed. FIG. 4 shows the results. 10 ^-2 lx to 1 lx
In the condition (3), the peak wavelength of the phosphorescent phosphor of 520 nm has the highest character recognition rate, and the peak wavelengths of 510 nm and 530 n
m also has a high character recognition rate. However, on the side having a shorter peak wavelength than 510 nm and the side having a longer peak wavelength than 530 nm, the character recognition rate is reduced. This indicates that under the condition of mesopic vision, light emission with a peak wavelength in the range of 520 nm and a range of 10 nm before and after 520 nm feels brighter to human eyes. On the other hand, under the condition of scotopic vision (10 ⁻³ lx), the recognition rate of characters was highest at 490 to 510 nm, and the correspondence with the standard relative luminous efficiency of scotopic vision was seen. From these results, it was found that the peak of standard relative luminosity in mesopic vision was located between the peak of standard luminosity of scotopic vision and the peak of standard relative luminosity of photopic vision shown in the figure. .

(3) Reduction in the Use of Phosphorescent Phosphors Next, using each phosphorescent phosphor having an emission peak at 490 nm, 520 nm, and 540 nm, the impregnation rate of the phosphorescent phosphor impregnated into the polyethylene terephthalate resin film is changed. The same experiment as (2) was carried out under mesopic conditions in the resin tube obtained, and the best result was obtained in the evaluation of (2).
The impregnation rates of the 490 nm and 540 nm phosphorescent phosphors into the polyethylene terephthalate resin, corresponding to obtaining the same character recognition rate as the 0 nm phosphorescent phosphor, were investigated.

In each of the phosphorescent materials having emission peaks at 490 nm, 520 nm, and 540 nm, the illuminance of the white plate on which the characters are drawn when the phosphorescent phosphor has an impregnation rate of 5% is 10 ^-1 lx.
(Adjusted to the same conditions as 10 ^-1 lx in (2)), and for lamps with a phosphor impregnated amount other than 5%, the time from turning off the lamp to conducting a character recognition test. Was carried out in the same manner as in the case of a lamp having a phosphorescent phosphor impregnation rate of 5%. In this case, more strictly, the relative luminous efficiency of the subject's eyes changes due to an increase or decrease in illuminance at a time other than the impregnation rate of 5% with respect to the impregnation rate of 5%, which may be included as an error. Thus, the range of illuminance in the obtained result is
Since it was in the range of 0.7 × 10 ⁻¹ lx to 1.5 × 10 ⁻¹ lx, it was determined that the effect of the change in the relative luminosity of the subject's eyes caused by the increase or decrease in the illuminance was extremely small. From the results shown in FIG. 5, it can be seen that when the peak wavelength is 520 nm,
The phosphorescent phosphor impregnation rate required to obtain a recognition rate of 0% is 3
% (Down 40%). Further, in the case of a peak wavelength of 520 nm, the impregnation rate of the phosphorescent phosphor necessary for obtaining the same recognition rate of 70% as that of 540 nm is only about 3.5% (reduced by about 30%). Conversely, in order to obtain the same recognition rate as 520 nm and an impregnation rate of 5%, the phosphorescent phosphor impregnation rate of 8% for 490 nm and 7% for 540 nm is required.

(4) Reduction in the amount of phosphor used to excite the phosphorescent phosphor Next, the peak wavelengths 490 nm and 540 used in (3) were used.
In the fluorescent lamps in which the phosphorescent material of 8 nm and the impregnation rate of polyethylene terephthalate resin are 8% and 7%, respectively.
The result of changing the amount of the three-wavelength mixed phosphor applied to the fluorescent lamp per lamp and the peak wavelength of 520 n
FIG. 6 shows the results obtained by changing the amount of adhesion of the three-wavelength mixed phosphor similarly with the impregnation rate of the phosphorescent phosphor of m being 5%. (3)
As shown in the figure, in order to obtain the same character recognition rate as that of the phosphorescent phosphor having a peak wavelength of 520 nm, in the case of the peak wavelengths of 490 nm and 540 nm, the impregnation rate of the phosphorescent phosphor is set to 8 respectively.
% And 7%. However, as described above, the brightness at the time of lighting of the fluorescent lamp decreases due to the increase in the impregnation rate of the phosphorescent phosphor. FIG. 6 shows that the peak wavelength is 490 nm, 5
To make the brightness of the fluorescent lamp at the time of lighting the same at the same character recognition rate as that of the phosphorescent light of the phosphorescent phosphor of 40 nm,
In the case of the phosphorescent phosphor having a peak wavelength of 520 nm, the amount of the three-wavelength mixed phosphor applied to the lamp per lamp is 2.4 g at a peak wavelength of 490 nm, and the peak wavelength is 5 g.
For 2.2 g of 40 nm, 1.9 g (about 15-20%
), The amount of the three-wavelength mixed phosphor used can be reduced.

In the embodiment of the present invention, a phosphor tube is formed by coating a fluorescent lamp with a resin tube in which a phosphor film is impregnated in a resin film. As described in the cross-sectional structure example, a phosphorescent phosphor layer is formed by applying a phosphorescent phosphor on the non-discharge side of the inner surface of the lamp glass bulb, and a phosphorescent phosphor such as a three-wavelength mixed phosphor is excited on the discharge side. The same effect can be obtained in a fluorescent lamp with a light storage function coated with a fluorescent material.

Also, a case has been described in which a three-wavelength mixed phosphor is used as the phosphor for exciting the phosphorescent phosphor, but a two-wavelength mixed phosphor may be used. Further, a one-wavelength phosphor may be used. The phosphor may be any phosphor that generates light that can be stored in the phosphorescent phosphor (excites the phosphorescent phosphor). Further, the phosphorescent phosphor may be a phosphor called a long persistence phosphor.

[Brief description of the drawings]

FIG. 1 is a diagram showing a range of illuminance in which a visual system works.

FIG. 2 is a diagram showing a relative luminous efficiency curve of a human eye and an emission spectrum of a phosphorescent phosphor (conventional example).

FIG. 3 is a diagram in which a phosphorescent phosphor layer is formed on the outer surface of a glass bulb of a fluorescent lamp.

FIG. 4 is a diagram illustrating a recognition rate of a phosphorescent substance and a character.

FIG. 5 is a diagram showing a relationship between a phosphorescent phosphor impregnation rate (%) impregnated in polyethylene terephthalate resin and a character recognition rate (%).

FIG. 6 is a graph showing a relationship between the adhesion amount (g) of a three-wavelength mixed phosphor applied to a fluorescent lamp per lamp and a relative brightness value (%) when the fluorescent lamp is turned on.

FIG. 7 is a diagram in which a phosphorescent phosphor layer is formed on the inner surface of a glass bulb of a fluorescent lamp.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Katsuo Murakami, Inventor 64, Tanyo, Kakegawa-shi, Shizuoka Prefecture F-term in Kakegawa Plant of Osram Melco Co., Ltd.

Claims (7)

[Claims] 1. A fluorescent lamp with a light storage function comprising two phosphor layers, a phosphorescent phosphor layer and a phosphor layer for exciting the phosphorescent phosphor layer, wherein the phosphorescent phosphor has an emission peak wavelength of 510.
530 nm, a fluorescent lamp with a luminous function. 2. The phosphorescent phosphor layer is applied to a non-discharge side of a lamp tube of a fluorescent lamp, and the phosphor layer for exciting the phosphorescent phosphor layer is applied to a discharge side of a lamp tube of the fluorescent lamp. The fluorescent lamp with a luminous function according to claim 1, wherein: 3. The phosphorescent phosphor layer is a layer in which a phosphorescent phosphor is impregnated in a resin tube coated on an outer surface of a lamp tube of a fluorescent lamp, and the phosphorescent layer that excites the phosphorescent phosphor layer is:
3. The fluorescent lamp with a luminous function according to claim 1, wherein the fluorescent lamp is coated on an inner surface of a lamp tube of the fluorescent lamp. 4. The fluorescent lamp with a luminous function according to claim 1, wherein the luminous phosphor is dysprosium, europium-activated strontium aluminate or dysprosium, europium-activated strontium boroaluminate. 5. The phosphor layer that excites the phosphorescent phosphor,
A red phosphor having an emission peak near a wavelength of 610 nm,
A green phosphor having an emission peak near a wavelength of 545 nm;
4. The fluorescent lamp with a luminous function according to claim 1, wherein the fluorescent lamp is a mixed phosphor of at least any two of a blue phosphor having an emission peak near a wavelength of 450 nm. 6. The fluorescent lamp with a luminous function according to claim 3, wherein the resin tube is impregnated with the luminous phosphor by 3% to 5%. 7. The fluorescent lamp with a phosphorescent function, wherein the amount of phosphor in the phosphor layer that excites the phosphorescent phosphor layer is larger than that of a phosphorescent lamp with a phosphorescent function whose emission peak wavelength is around 490 nm. 4. The fluorescent lamp with a luminous function according to claim 1, wherein the amount is reduced by about 20%.