JP2008210633A - Fluorescent lamp and yellow light source device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light source device needing yellow-light emission capable of emitting yellow light in a simple structure without any pigment layer prepared, for instance, a noxious insect evasion light for evading insects flying into an orchard, an illumination lamp in a working room at a photolithography process in a semiconductor manufacturing factory, a fluorescent lamp suitable for a vegetable cultivation light source or the like accelerating growth of vegetables, and, especially, a fluorescent lamp capable of emitting yellow-color light with the use of a kind of YAG phosphor enabled to obtain high-intensity light emission without color shifts. <P>SOLUTION: The fluorescent lamp includes a translucent vessel 12 sealing in gas containing mercury generating ultraviolet rays by discharge, and a phosphor layer 18 fitted to an inner wall face of the translucent vessel 12. The phosphor layer 18 contains a YAG phosphor emitting yellow-color light by an ultraviolet ray of 253.7 nm irradiated from mercury atoms. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fluorescent lamp that emits yellow light using a YAG phosphor and a yellow light source device.

Conventionally, pest repellent lamps incorporating yellow fluorescent lamps that emit light in the wavelength range of 500 nm to 700 nm, etc. have been used in orchards in order to avoid the infestation of pests such as night moths that fly at night to harm fruits Has been. Further, in a semiconductor manufacturing factory, a fluorescent lamp that emits yellow light is used for illumination of a working room where a photolithography process is performed. As this type of fluorescent lamp, in order to obtain yellow light emission, as shown in FIG. 4, phosphors each emitting light of wavelengths in different regions, Ca ₁₀ (PO ₄ ) ₆ FCl having a color temperature of 2300 K: A phosphor layer 31 containing Sb, Mn (antimony, manganese-activated calcium halophosphate phosphor) is provided in the glass tube 32, and the fluorescence emitted from the phosphor layer is transmitted between the phosphor layer and the glass tube. It is known to transmit yellow light by transmitting a pigment layer 33 such as yellow titanium provided. Further, as a fluorescent lamp capable of emitting yellow light without providing such a pigment layer, antimony and manganese activated calcium halophosphate phosphors having an emission peak wavelength in the vicinity of 586 nm, and europium having an emission peak wavelength in the vicinity of 611 nm. A fluorescent lamp for controlling pests using a mixture with an activated yttrium oxide phosphor or the like (Patent Document 1) has been reported.

  On the other hand, in an illuminating device using a blue light emitting diode (LED), a YAG phosphor is used in order to produce a color rendering effect by emitting fluorescence of green yellow light or orange red light excited by blue from the LED. A known discharge lamp using this YAG phosphor has been reported (Patent Document 2). This discharge lamp uses a YAG phosphor as a phosphor component to improve color efficiency due to damage to the phosphor component and to improve quantum efficiency in excitation, but electromagnetic waves in the VUV region (200 nm or less). The first phosphor layer containing a component that generates an electromagnetic wave in the UVA region and the second phosphor layer containing a component that generates an electromagnetic wave in the visible region when excited by the electromagnetic wave in the UVA region.

  In addition, lighting devices such as fluorescent display tubes and fluorescent lamps using a phosphor mixture containing a YAG phosphor have been reported (Patent Document 3). However, this phosphor mixture also suppresses color misregistration and exhibits color rendering properties. It is intended to improve the emission intensity, and obtains white light with high emission intensity by combining specific phosphors.

Further, a fluorescent high-pressure mercury lamp using a phosphor containing a YAG phosphor has been reported (Patent Document 4). In this fluorescent high-pressure mercury lamp, in order to improve the color rendering by suppressing the output of the mercury emission line in the blue region. _{Although 3} Al ₅ O ₁₂ : Ce is used, yellow-green light emission is obtained by excitation at 365 nm.

  Further, a low-pressure mercury vapor discharge lamp using a YAG phosphor (Patent Document 5) has been reported. The YAG phosphor used here is a phosphor having an emission peak wavelength in the near infrared region.

All of these fluorescent lamps and the like contain a YAG phosphor as a phosphor, but various phosphors are mixed and used to obtain pure yellow light emission by the phosphor layer containing the YAG phosphor. Things are not known.
JP-A-1-187757 JP 2004-363102 A JP 2006-241249 A JP-A-61-68854 JP-A-9-199086

  An object of the present invention is to provide a light source device that can emit yellow light with a simple structure without providing a pigment layer and the like, for example, to repel pests flying into an orchard. An object of the present invention is to provide a fluorescent lamp suitable for a pest repellent lamp, an illumination lamp in a working room of a photolithography process in a semiconductor manufacturing factory, a plant cultivation light source for promoting plant growth, and the like. In particular, an object of the present invention is to provide a fluorescent lamp capable of emitting yellow light by using one kind of YAG phosphor, and thereby obtaining high-intensity light emission without causing color shift.

As a result of diligent research, the present inventors paid attention to the fact that the YAG phosphor emits yellow light by ultraviolet rays of 253.7 nm emitted from mercury atoms. In the fluorescent lamp, the inventors emitted radiation from mercury atoms that received discharge electrons. It was found that the yellow light from the YAG phosphor can be emitted without providing a pigment layer or the like by the ultraviolet ray of 253.7 nm. Furthermore, by using only Y ₃ Al ₅ O ₁₂ activated with cerium as the YAG phosphor, one type of phosphor can emit yellow light, thereby causing no color shift and high intensity. The knowledge that it was possible to obtain light emission was obtained. Based on this finding, the present invention has been completed.

  That is, the present invention relates to a fluorescent lamp having a translucent container enclosing a gas containing mercury that generates ultraviolet rays by discharge, and a phosphor layer provided on the inner wall surface of the translucent container. And a fluorescent lamp characterized by containing a YAG phosphor that emits yellow light by light having a wavelength of 253.7 nm emitted from mercury atoms.

  The present invention also relates to a yellow light source device using the fluorescent lamp.

  The fluorescent lamp of the present invention can emit yellow light with a simple structure without providing a pigment layer or the like, and repels pests flying into an orchard, for example, a light source device that needs to emit yellow light. It can be suitably used as a pest repellent lamp, an illuminating lamp in a working room of a photolithography process in a semiconductor manufacturing factory, a plant cultivation light source that promotes plant growth, and the like. In particular, by using one kind of YAG phosphor, yellow light can be emitted by one kind of phosphor, and thereby high intensity light emission can be obtained without causing color shift.

  The fluorescent lamp of the present invention is a fluorescent lamp having a light-transmitting container in which a gas containing mercury that generates ultraviolet rays by discharge is hermetically sealed, and a phosphor layer provided on the inner wall surface of the light-transmitting container. The phosphor layer contains a YAG phosphor that emits yellow light by ultraviolet rays of 253.7 nm emitted from mercury.

  The translucent container used for the fluorescent lamp of the present invention may be any material as long as it is made of a material that transmits visible light, such as glass. The shape may be any of a straight tube type, a curved type, a ring shape, a valve type and the like.

  Mercury that generates ultraviolet rays by discharge is enclosed in the translucent container, and further, rare gas such as argon or neon is enclosed. Discharged electrons generated in the translucent container collide with mercury atoms and generate ultraviolet rays including 253.7 nm. Examples of the vapor pressure of mercury to be sealed include 1 to 10 Pa when the fluorescent lamp is turned on.

  Examples of means for generating a discharge in the translucent container include an electrode made of a tungsten coil coated with an emitter material such as an oxide such as barium, calcium, yttrium, or the like. When an external charge is applied to this electrode, electrons are emitted from the emitter material.

The phosphor layer provided on the inner wall of such a translucent container contains a YAG phosphor that emits yellow light by ultraviolet rays of 253.7 nm emitted from mercury atoms. Since YAG phosphors are less deteriorated by heat and less mercury is adsorbed, the mercury vapor pressure may continue to be high at the time of starting the fluorescent lamp. It is possible to suppress the deterioration of the transparent container due to mercury adsorbed. As the YAG phosphor, Y ₃ Al ₅ O ₁₂ (Y ₃ Al ₅ O ₁₂ : Ce) activated with cerium is preferable. By using Y ₃ Al ₅ O ₁₂ : Ce, pure yellow light emission of 580 to 595 nm can be obtained by 253.7 nm ultraviolet rays emitted from mercury, as shown in FIG. For this reason, by using only Y ₃ Al ₅ O ₁₂ : Ce as the phosphor, the emission intensity can be increased without causing color misalignment or the like in the fluorescent lamp, and the fluorescence of a light source device or the like that requires yellow light. It is suitable for a lamp. In addition to the YAG phosphor that emits yellow light by 253.7 nm ultraviolet rays emitted from mercury, the phosphor layer is excited from the near infrared rays by being excited by 253.7 nm ultraviolet rays emitted from mercury. For general fluorescent lamps for illumination that obtain white light with excellent color rendering, including YAG phosphors that emit visible light such as red, blue, yellow-green, and green, and phosphors other than YAG phosphors It is also possible to do.

Such a phosphor layer is preferably provided so as to contain 6 mg to 10 mg of YAG phosphor per 1 cm ² . If the content of the YAG phosphor in the phosphor layer is 6 mg or more per 1 cm ² , leakage of ultraviolet rays near 360 nm generated from 10 mg mercury can be suppressed, and if it is 10 mg or less, visible light from the phosphor layer can be suppressed. A decrease in transmittance can be suppressed. Examples of the thickness of the phosphor layer include about 50 μm to 60 μm.

  The fluorescent lamp of the present invention suppresses leakage of ultraviolet rays near 360 nm between the phosphor layer and the transparent container, or on the discharge space side in the transparent container, or deterioration of the transparent container due to mercury or the like. In order to suppress this, a protective layer may be provided. The protective layer can be formed using, for example, a metal oxide such as yttrium oxide, aluminum oxide, or cerium oxide. The thickness of the protective layer can be about 1 to 4 μm.

  As a lighting circuit for driving this type of fluorescent lamp, a starter type lighting circuit that preheats an electrode and generates a high-pressure pulse by a lighting circuit provided separately from the fluorescent lamp can be used, but is provided integrally with the fluorescent lamp. Further, a rapid start type lighting circuit including a ballast having an electrode preheating circuit and a booster circuit, and an inverter type lighting circuit including a high frequency conversion circuit can also be used. When the lighting circuit is provided in an integrated manner, the transparent container is curved or bent, the surroundings are further covered with a globe, and the light-bulb type having a base connected to the lighting circuit has a structure in which the transparent container is exposed to the outside. Also good.

  The method for producing such a fluorescent lamp is not particularly limited, and a dispersion liquid in which the YAG phosphor is dispersed in a solvent is prepared, and this is used for a transparent container made of glass or the like having a predetermined shape. The inner wall surface is coated by a method such as dipping or spraying to a predetermined thickness. Thereafter, an electrode can be provided at the end of the transparent container and sealed with a base having an external lead or the like connected to the electrode.

The fluorescent lamp of the present invention is one in which a YAG phosphor emits yellow light by ultraviolet rays of 253.7 nm emitted from mercury atoms, and is used together with a YAG phosphor that generates visible light such as red and blue, etc. However, only a YAG phosphor that generates yellow light, more preferably, only Y ₃ Al ₅ O ₁₂ : Ce is used, and can be suitably applied to a yellow light source device. . The yellow light source device can be suitably applied to pest repellent lamps, plant cultivation light sources, illumination lamps in semiconductor manufacturing factories, and the like.

  The present invention will be described in more detail with reference to the following examples, but the technical scope of the present invention is not limited thereto.

  An example in which the fluorescent lamp of the present invention is applied to a straight tube fluorescent lamp will be described with reference to the drawings. The straight tube type fluorescent lamp shown in the block diagram of FIG. 2 has a straight tubular glass tube 12 having a tube inner diameter of 15 to 38 mm constituting a transparent container, and stems 11 for closing both ends thereof. The stem 11 is provided with a pair of lead wires 14, and is formed of a tungsten filament coated with an emitter of an electron emitting material such as barium oxide, strontium oxide, calcium oxide between the lead wires and functions as a hot cathode. An electrode 15 is provided. Each lead wire is connected to a terminal 16 protruding from a base 16 that holds the glass tube in an airtight manner, and external power is applied to the electrode 15 through the lead wire. A phosphor layer 18 is provided on the inner wall surface of the glass tube 12 and mercury is sealed in an airtight interior so that the vapor pressure during lighting is 1 to 10 Pa. The rare gas is enclosed as 3 Torr or the like.

As shown in FIG. 3, the phosphor layer 18 provided on the inner wall surface of the glass tube is provided on the inner wall of the glass tube with a thickness of 50 to 60 μm, for example. The phosphor layer contains only Y ₃ Al ₅ O ₁₂ : Ce, and is provided as 6 mg to 10 mg per 1 cm ² . Since the phosphor contained in the phosphor layer is in the above range, 360 nm wavelength light emitted from mercury is blocked by the phosphor layer, and leakage outside the glass tube is suppressed.

  Although the glass tube is not provided with a protective layer, a protective layer such as yttrium oxide or aluminum oxide is provided between the inner wall surface of the crow tube and the phosphor layer, so that light having a wavelength of 360 nm emitted from mercury is emitted. You may make it suppress the leakage to the glass tube exterior. Specific examples of the thickness of the protective layer include 1 to 4 μm.

The operation of such a straight tube fluorescent lamp will be described. When current is applied to the electrode (cathode) through the terminal 17 and the lead wire to preheat, electrons are emitted from the emitter that has become high temperature. The emitted electrons are attracted and moved by the electrode (anode), and discharge starts. When the discharge electrons collide with mercury atoms, ultraviolet rays of 253.7 nm are emitted from the mercury atoms. This ultraviolet ray is absorbed by the phosphor layer Y ₃ Al ₅ O ₁₂ : Ce phosphor and emits yellow light of 580 to 595 nm. At this time, the ultraviolet rays near 360 nm emitted from mercury are suppressed from being emitted outside the glass tube by the phosphor layer.

It is a figure which shows the spectral intensity of the fluorescent substance used for the fluorescent lamp of this invention. It is a schematic block diagram which shows the straight tube | pipe type fluorescent lamp of an example of the fluorescent lamp of this invention. It is sectional drawing which shows the straight tube | pipe type fluorescent lamp shown in FIG. It is sectional drawing which shows the conventional fluorescent lamp.

Explanation of symbols

12 Glass tube (transparent container)
18 Phosphor layer

Claims (4)

  In a fluorescent lamp having a translucent container enclosing a gas containing mercury that generates ultraviolet rays by electric discharge and a phosphor layer provided on the inner wall surface of the translucent container, the phosphor layer emits from mercury atoms. A fluorescent lamp comprising a YAG phosphor that emits yellow light by ultraviolet rays of 253.7 nm. 2. The fluorescent lamp according to claim 1, wherein the YAG phosphor is composed only of Y ₃ Al ₅ O ₁₂ activated with cerium. The fluorescent lamp according to claim 1 or 2, wherein the phosphor layer contains 6 mg to 10 mg of YAG phosphor per 1 cm ² .   A yellow light source device using the fluorescent lamp according to claim 1.

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