GB1569366A - Creación de Inventos y Patentes con Inteligencia Artificial

GB1569366A – Discharge lamp
– Google Patents

GB1569366A – Discharge lamp
– Google Patents
Discharge lamp

Download PDF
Info

Publication number
GB1569366A

GB1569366A
GB11369/77A
GB1136977A
GB1569366A
GB 1569366 A
GB1569366 A
GB 1569366A
GB 11369/77 A
GB11369/77 A
GB 11369/77A
GB 1136977 A
GB1136977 A
GB 1136977A
GB 1569366 A
GB1569366 A
GB 1569366A
Authority
GB
United Kingdom
Prior art keywords
envelope
radiation
lamp
lamp according
suppressing means
Prior art date
1976-03-19
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)

Expired

Application number
GB11369/77A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)

Panasonic Holdings Corp

Original Assignee
Matsushita Electronics Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
1976-03-19
Filing date
1977-03-17
Publication date
1980-06-11

1976-03-19
Priority claimed from JP3019076A
external-priority
patent/JPS52113580A/en

1976-09-20
Priority claimed from JP11342976A
external-priority
patent/JPS5338176A/en

1976-09-20
Priority claimed from JP11343276A
external-priority
patent/JPS5338179A/en

1977-03-17
Application filed by Matsushita Electronics Corp
filed
Critical
Matsushita Electronics Corp

1980-06-11
Publication of GB1569366A
publication
Critical
patent/GB1569366A/en

Status
Expired
legal-status
Critical
Current

Links

Espacenet

Global Dossier

Discuss

Classifications

H—ELECTRICITY

H01—ELECTRIC ELEMENTS

H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS

H01J61/00—Gas-discharge or vapour-discharge lamps

H01J61/02—Details

H01J61/38—Devices for influencing the colour or wavelength of the light

Description

PATENT SPECIFICATION
( 11) 1569366 ( 21) Application No 11369/77 ( 22) Filed 17 March 1977 ( 31) Convention Application No 51/030 190 ( 32) Filed 19 March 1976 ( 31) Convention Application Nos 51/113 429 and 51/113 432 ( 32) Filed 20 Sept 1976 in ( 33) Japan (JP) ( 44) Complete Specification published 11 June 1980 ( 51) INT CL 3 HO 1 J 61/38, 61/30/161/22, 61/40 ( 52) Index at acceptance H 1 D 12 B 13 Y 12 B 1 12 B 2 12 B 3 12 B 47 Y 12 B 4 12 C 35 5 H 5 P 3 9 A 9 B 9 C 2 9 CX 9 CY 9 D 9 Y F 4 R 203 466 469 547 CK ( 72) Inventors YOSHIAKI WATARAI, HARUO YAMAZAKI, NAOKI SAITO, MASAYUKI YAMAGUCHI, TAKIO OKAMOTO and HIDEZO AKUTSU ( 54) A DISCHARGE LAMP ( 71) We, MATSUSHITA ELECTRONICS CORPORATION, a Japanese Corporation organized under the laws of Japan, of 1006, Oaza-Kadoma, Kadoma City, O Prefecture, Japan, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly
described in and by the following statement:-
The present invention relates generally to a high pressure vapor discharge lamp using an alumina tube which is translucent or transparent and in which sodium vapour for producing radiation, a buffer gas and an inert starting gas are contained.
As described in column 3, lines 58-65 of U.S Patent 3,898,504, a high pressure sodium vapor discharge lamp can be designed to have a good color rendition, even having a color acceptability of over 1 0 when operated.
The said U S Patent discloses a high pressure sodium vapor discharge lamp comprising a tube envelope containing therein sodium, inert starting gas, buffer gas comprising at least one of mercury and cadmium and discharge electrodes sealed in said envelope, said lamp satisfying the following relation between the tube diameter d in millimeters and an average potential gradient E in volts per centimeter E > 37 7 2 05 d, wherein E 6 25 and d > 9.
However, it is difficult to realize in practice a high pressure sodium vapor discharge lamp having a color temperature of over 25000 K.
Though it is theoretically possible to raise the color temperature to a value from 2500 K to 3500 K simply by raising sodium vapor pressure in the discharge tube, such a raising of the vapor pressure results in shortcomings.
For example, the lamp has a lower efficiency and an excessively increased lamp voltage, and so has a lesser utility The terms ‘general color rendering index’, the ‘color temperature’ and color acceptability’ of the lamp are used herein as defined and elucidated in C I E.
(Commission Internationate de l’Eclairage) recommendation.
According to the invention, there is provided a high pressure sodium vapor discharge lamp comprising an inner tubular envelope of alumina, containing therein sodium vapour, an inert starting gas, a source of buffer gas and discharge electrodes sealed in the envelope, in which the inner diameter d in mm of the envelope and the average potential gradient E in v/cm have the relation E > 37 7 2 05 d; said tubular envelope being mounted within an outer housing or envelope at least part of which is translucent to the emission from the inner, tubular envelope, said outer housing or envelope comprising radiation suppressing means for selectively absorbing red radiation emanating from the inner tubular envelope and having a wavelength longer than 60 nm.
In the accompanying drawings:FIG 1 is a partial sectional side view of a discharge tube illustrating an exemplary lamp structure embodying the present invention.
FIG 2 is a side view of a high pressure sodium vapour discharge lamp wherein the discharge tube of Fig 1 is contained.
FIG 3 is a graph showing the spectral characteristic of light transmittivity of a light suppressing means used in the lamp of FIG.
2 embodying the present invention.
FIG 4 is a graph showing spectral power CD es h Z 1,569,366 distribution of light of the lamp of FIG 2.
FIG 5 is a side view of another high pressure sodium vapor discharge lamp wherein the discharge tube of FIG 1 is contained.
FIG 6 is a graph showing the spectral characteristic of light reflectivity of another light suppressing means used in another lamp of FIG 5 embodying the present invention.
FIG 7 is a graph showing spectral power distribution of light of the lamp of FIG 5.
FIG 8 is a graph showing relations of color temperature Tc (in absolute temperature K), decrease of efficiency An (in %) and general color rendering index Ra of the lamp embodying the present invention against the cut-off wave length Ac (in nm) of the light suppressing means.
FIG 9 is a partial sectional side view of still another high pressure sodium vapor discharge lamp of the present invention.
The high pressure sodium vapor discharge lamp of a preferred example comprises a discharge tube 1 shown in FIG 1, wherein the tube envelope 2 is made of translucent polycrystalline alumina having a pair of electrodes supported by lead-in metal tube 4 and 4 made of niobium The niobium tubes 4 and 4 penetrate and are supported by the end discs 3 and 3 which are made of ceramic and seal both ends of the tube envelope 2 The tube envelope 2 contains sodium as a metal for producing radiation, mercury or cadmium as a buffer gas and xenon as a starting inert gas The tube envelope 2 has an inner diameter d in the range of 6 3 mm to 13 5 mm The inter-electrode gap L is in the range of 25 mm to 82 mm The amount of the sodium is in the range of 3 mg to 15 mg, and the amount of the mercury is in the range of 3 mg to 60 mg for each tube envelope Xenon as the starting inert gas is contained so as to have a pressure of about 20 Torr at room temperature.
Some modification can be made by using the following equivalent substances in place of the abovementioned parts and elements:
The tube envelope 2 can be made of singlecrystalline alumina The metal as the source of the buffer gas can be 10 mg to 80 mg of cadmium The starting inert gas can be about Torr in room temperature of neon-argon penning gas (Ne added by 0 1 to 1 0 % of Ar).
The discharge tube 1 is sealed in an outer bulb 7 as shown in FIG 2, wherein both lead-in metal tubes 4 and 4 are connected toknown base metals 71 and 72 In general the inside space of the outer bulb 7 is evacuated.
The outer bulb 7 is made of an infra-red or heat ray absorbing glass as a radiation suppressing means, for example a glass containing phosphorus pentoxide (P 20 j) as a principal part and a small amount of ferrous oxide (Fe O) The spectral characteristic of the above-mentioned glass of the outer bulb 7 is, as shown in FIG 3, to suppress the radiant power of the spectral components exceeding the wave length of about 600 nm.
Accordingly, in an actual example of the discharge tube 1 which is designed to operate 70 at the tube input power of 400 watts, the spectral power distribution of the radiant power is satisfactorily improved as shown by the curve «a» of FIG 4 in contrast to that of dotted curve «b» for the similar lamp with 75 conventional non-colored outer bulb of molybdenum glass (ordinary hard glass) As shown in FIG 4, in the spectral power distribution of the light of the lamp of the present invention, part of the radiant power in the range 80 of the wave length of over 620 nm is considerably suppressed by the bluish colored heatray absorbing glass, and accordingly, the resultant color temperature of the lamp becomes 3030 ‘K and general color rendering 85 index becomes about 86 The abovementioned color temperature of 3030 K is much improved from that of 2500 K of the conventional one.
As a modified example, a layer or film of the abovementioned heat ray glass or powder of 90 bluish inorganic pigment, e g, cerulean blue, prussian blue and cobalt blue can be coated on substantial part of the inner surface of the conventional non-colored outer bulb of ordinary hard glass 95 In another example shown in FIG 5, the discharge tube elucidated in the above referring to FIG 1, is disposed and sealed in a reflector hood 9 having a reflection film 8 formed on the inside face of the rear wall 100 Opposite the reflective surface is a window member translucent to the reflected radiation.
The reflection film 8 is a film having the characteristic of suppressing the spectral component of reflected light of the wave length 105 of over 620 nm Namely, the reflection film 8 as the light suppressing means well reflects blue and green radiation and less reflects red radiation, partly absorbing the latter For such reflection film 8, a multi-layered vapor de 110 posited film comprising layers of magnesium fluoride (Mg F 2) and zinc sulfide (Zn S) may be used FIG 6 shows spectral characteristic of the light reflectivity of the multi-layered Mg F,-Zn S reflection film 8 As shown in 115 FIG 6, the reflectivity is below 60 % for the light of wave length of over 620 nm FIG 7 shows spectral power distribution of the radiation of the lamp of FIG 5 By means of the suppressing red radiation of the wave length 120 longer than 620 nm by the reflection film 8, the color temperature is improved The characteristic of the finished lamp is that the tube input power is 150 watts, the color temperature is 2980 K and general color rendering 125 index is 85.
FIG 9 shows another embodiment wherein a high pressure sodium vapor discharge lamp with outer bulb of ordinary non-colored hard glass is disposed in a reflector hood, 130 1,569,366 which comprises a front panel 11 of a heatray absorbing glass as a light absorbing means.
The heat-ray absorbing glass is, for example, a glass containing phosphorus pentoxide (P 20 J) as a principal part and a small amount of ferrous oxide (Fe O) and suppresses the transmission of light of the wave length over 620 rn.
Table 1 is a comparison table for the characteristics of examples of the high pressure sodium vapor discharge lamps of the present invention which lamps are made to have color temperatures of about 30000 K with using the discharge tube having the color temperature of about 2500 CK, compared with those of the examples of conventional high pressure sodium vapor discharge lamps which are made to have similar color temperature (i e about 30000 K) by considerably raising the sodium vapor pressure.
TABLE 1
Present Invention Example of FIG 2 FIG 2 FIG 5 FIG 9 Prior Art
Type of 150 watts 400 watts 150 watts 150 watts 150 watts 400 watts inner diameter «d» 7 6 mm 11 5 mm 7 6 mm 7 6 mm 7 6 mm 11 5 mm interelectrode gap «L» 35 mm 52 mm 35 mm 35 mm 35 mm 52 mm substance Na 8 6 mg : contained Hg 32 mg same to the left in the Xe 20 Torr zo tube light outer bulb same to reflection front panel nil same to suppres of heat the left film of of heat the left sing absorbing red light absorbing bulb is of means glass absorbing glass for ordinary nature on lamp hood hard glass the rear (molybdenum part of the glass) outer bulb input power 150 w 400 w 150 w 150 w 150 w 400 w.
lamp voltage 103 v 118 v 100 v 103 v 142 v 172 v.
color temperature 3010 K 3030 K 3010 K 3010 K 2990 K 3000 K n O general color rendering index 87 86 85 87 72 71 efficiency 53 lm/w 71 lm ‘w 38 lm /w 50 lm/w When (Ne + O 5 % Ar)-gas of 20 Torr is sealed instead of Xe, the efficiency decreases by several percent from the above table, but other values remain substantially unchanged.
1,569,366 1,569,366 As can be understood from the table 1, the lamps embodying the present invention show good color rendition and efficiency for the color temperature of about 3004 K, while the lamps of the prior art requires fairly high lamp voltage, have considerably low efficiency and poor color rendition when made to achieve inner diameter d inter-electrodegap L substance contained in the tube Na Hg Xe input power color temperatures The simulation was carried out under the condition that the radiant power from the discharge tubes of the abovementioned examples are suppressed by an ideal high pass color filter as the light suppressing means which allows to pass radiation of wave lengths under the cut-off wave length Ac and cut off radiadon of wave lengths on and over Ac In FIG.
8, solid lines a, b and c indicate color temperature, decrease of efficiency (due to the color filter) and general color rendering index for the discharge tube of the color temperature of 2500 K; dotted lines a’, b’ and c’ indicate those for the discharge tube of the color temperature of 2800 K.
According to the curves of FIG 8, the color temperature curves a and a’ have maximum gradients in the range of the cut-off wave length Ac of 620-650 nm Therefore, by selecting the cut-off wave length in the range of 620 to 650 nm, the color temperature of the lamp can be selected within a wide range of ‘3000 K to 6000 K for the discharge tube having its color temperature of 2800 K, or in the range of 2800 K to 5000 K for the discharge tube having its color temperature of 2500 K Furthermore, for such range of the cut-off wave length, the decreases of the efficiencies of the lamps are at largest within only 20 %, and such a high value of general color rendition index Ra of 60 to 90 are obtainable For the cut-off wave length Ac shorter than 620 nm, the general color rendering index Ra rapidly falls, resulting in poor color rendition For the cut-off wave length of over 650 un, the color temperature Tc is not raised.
The curves c and c’ for the general color rendering index have peaks in the range of the cut-off wave length of 620-650 nm.
Namely, as the cut-off wave length becomes shorter from 630 nm towards 700 nm, the general color rendering index Ra becomes large This phenomenon is peculiar to the high pressure sodium vapor discharge lamp, wherein broadening of the radiant power of the discharge tube becomes dominant in all such a high color temperature of about 3000 K.
FIG 8 shows curves of computer simula 10 tion for the lamps of the structure of FIG 2 wherein details of the discharge tubes are as follows:
11.5 mm 52 mm 8.6 mg 32 mg Torr 400 & 450 w for 2500 K & 2800 K, respectively.
the way of visual range, as the sodium vapor pressure increases Especially, when the sodium vapor pressure is so high that makes the colour temperature of 2300 K-2400 K or more (such condition is realized by raising the temperature of the coolest point of the tube), red radiant power becomes dominant.
Accordingly the flattening effect for the red color region becomes excessive, thereby lowering the general color rendering index Ra.
Therefore, as elucidated in the above, cuttingoff of the excessive red radiant light results in improving the general color rendering index Ra The abovementioned phenomenon peculiar to the high pressure sodium vapor discharge tube can be observed only for a discharging condition with the sodium vapor pressure of above a specified level Such condition of the sodium vapor pressure is obtainable when the following condition is satisfied:
E > 37 7 2 05 d, wherein E(v/cm) is an average voltage 90 gradient and d(mm) is the inner diameter of the discharge tube.
With a lower average voltage gradient that can not satisfy the abovementioned inequality, even if the radiant power of the long wave 95 length range is cut off, the general color rendering index Ra of FIG 8 can not be raised, and only the color temperature is raised.
Though the abovementioned computer 100 simulation is based on the condition of using an ideal light absorbing means, i e, an ideal high pass color filter, the simulation is well approved by experiments.
As elucidated in the above, a raising of the 105 color temperature of the discharge tube per se of the high pressure sodium discharge lamp results in sacrificing the life of the lamp.
Especially, for the color temperature of the discharge tube of over 2800 K, the life be 110 comes very short Accordingly, the operating condition of the discharge tube should be selected in a manner to maintain the color is 5 S 6,6,6 temperature of the discharge tube to be lower than 2800 ‘K In order to ensure more stable long life operation, it is preferable to select the color temperature of the discharge lamp to be lower than 2700 ‘K.
According to the present invention, a resultant color temperature of the lamp of about 30000 K or higher can be achieved with using a discharging tube having the color temperature of around 2500 ‘K or the like, together with achievement of good efficiency and high color rendition.
Since high color rendition and high color temperature is obtainable, the lamp of the present invention is suitable for use in indoor illumination.

Claims (1)

WHAT WE CLAIM IS:-
1 A high pressure sodium vapour discharge lamp comprising a tubular envelope of alumina, containing therein sodium vapour, an inert starting gas, a source of buffer gas and discharge electrodes sealed in the envelope, in which the inner diameter d in mm of the envelope and the average potential gradient E in v/cm have the relation E > 37 7 2 05 d; said tubular envelope being mounted within an outer housing or envelope at least part of which is translucent to the emission from the inner, tubular envelope, said outer housing or envelope comprising radiation suppressing means for selectively absorbing red radiation emanating from the inner tubular envelope and having a wavelength longer than 620 nmn.
2 A lamp according to claim 1, wherein said radiation suppressing means is a radiationfiltering substance which passes radiation of the wavelength of 620 nm or shorter and suppresses wavelengths longer than 620 nm.
3 A lamp according to claim 2, wherein said radiation suppressing means has a cutoff wavelength in the range of 620-650 nm.
4 A lamp according to claim 1 or claim 2, wherein said radiation suppressing means is a heat absorbing glass containing phosphorus pentoxide as a principal component and a small amount of ferrous oxide as additive.
A lamp according to claim 4, wherein the heat absorbing glass is formed as a bulb enclosing the tubular envelope and constituting 50 said outer housing or envelope.
6 A lamp according to claim 1, wherein said outer housing or envelope is in the form of a reflector hood enclosing the inner, tubular envelope, said hood having a reflective surface 55 capable of reflecting radiation emissions from the inner tube, said hood further comprising a window member mounted opposite said reflective surface for transmission from the hood of the reflected radiation, said window 60 member comprising said radiation suppressing means.
7 A lamp according to claim 6, wherein said window member is of a heat absorbing glass as defined in claim 4 65 8 A lamp according to claim 1, wherein said radiation suppressing means is a film which reflects radiation of a wave length of 620 nm or shorter and suppresses reflection of radiation having a wavelength longer than 70 620 nm.
9 A lamp according to claim 6, wherein said radiation suppressing means is a multilayered film comprising layers of magnesium fluoride and zinc sulfide 75 A high pressure sodium vapour discharge lamp of claim 9, wherein said multilayered film is coated upon an inside face of a rear wall of a reflector hood enclosing the tubular envelope and constituting said outer 80 housing or envelope, said reflector hood comprising a window translucent to the reflected radiation mounted therein opposite the reflective surface for the transmission of radiation from the lamp 85 11 A lamp according to claim 2, wherein the radiation-filtering substance is a coating of bluish inorganic powder formed on the inner face of a translucent bulb enclosing the inner tubular envelope and constituting said 90 outer housing or envelope.
12 A sodium vapour discharge lamp substantially as herein described with reference to and as illustrated in Fig 1, or Fig 2, or Fig 5, or Fig 9 of the accompanying 95 drawings.
For the Applicants, D YOUNG & CO, Chartered Patent Agents, 9 & 10 Staple Inn, London, WC 1 V 7RD.
Printed for Her Majesty’s Stationery Office by the Courier Press, Leamington-Spa, 1980.
Published by the Patent Office, 25 Southampton Buildings, London, WC 2 A l AY, from which copies may be obtained.
1,569,366 At

GB11369/77A
1976-03-19
1977-03-17
Discharge lamp

Expired

GB1569366A
(en)

Applications Claiming Priority (3)

Application Number
Priority Date
Filing Date
Title

JP3019076A

JPS52113580A
(en)

1976-03-19
1976-03-19
High pressure metal vapor discharge apparatus

JP11342976A

JPS5338176A
(en)

1976-09-20
1976-09-20
High pressure metal vapor discharge apparatus

JP11343276A

JPS5338179A
(en)

1976-09-20
1976-09-20
High pressure metal vapor discharge apparatus

Publications (1)

Publication Number
Publication Date

GB1569366A
true

GB1569366A
(en)

1980-06-11

Family
ID=27286872
Family Applications (1)

Application Number
Title
Priority Date
Filing Date

GB11369/77A
Expired

GB1569366A
(en)

1976-03-19
1977-03-17
Discharge lamp

Country Status (5)

Country
Link

US
(1)

US4109175A
(en)

CA
(1)

CA1064566A
(en)

DE
(1)

DE2711733C2
(en)

FR
(1)

FR2344961A1
(en)

GB
(1)

GB1569366A
(en)

Cited By (1)

* Cited by examiner, † Cited by third party

Publication number
Priority date
Publication date
Assignee
Title

GB2145557A
(en)

1983-08-13
1985-03-27
Emi Plc Thorn
Improvements in discharge lamps

Families Citing this family (6)

* Cited by examiner, † Cited by third party

Publication number
Priority date
Publication date
Assignee
Title

NL179855C
(en)

1978-02-22
1986-11-17
Philips Nv

HIGH PRESSURE SODIUM VAPOR DISCHARGE LAMP.

US4197480A
(en)

1978-09-11
1980-04-08
Westinghouse Electric Corp.
Reflector-type hid sodium vapor lamp unit with dichroic reflector

US4527097A
(en)

1982-05-10
1985-07-02
U.S. Philips Corporation
High-pressure sodium discharge lamp

US4580075A
(en)

1982-11-26
1986-04-01
General Electric Company
High pressure sodium lamp having improved coloring rendition

US5079473A
(en)

1989-09-08
1992-01-07
John F. Waymouth Intellectual Property And Education Trust
Optical light source device

JP2001110367A
(en)

1999-10-06
2001-04-20
Ushio Inc
Incandescent lamp

Family Cites Families (8)

* Cited by examiner, † Cited by third party

Publication number
Priority date
Publication date
Assignee
Title

DE518015C
(en)

1929-07-12
1931-02-11
Patra Patent Treuhand

Electric light tubes

BE631753A
(en)

1962-05-02

DE1496658B2
(en)

1963-06-25
1971-12-09
Saale-Glas GmbH, χ 6900 Jena

HEAT-ABSORBING WEATHER-RESISTANT PHOSPHATE GLASS

DE1260627B
(en)

1965-11-13
1968-02-08
Philips Nv

Sodium Discharge Lamp

US3898504A
(en)

1970-12-09
1975-08-05
Matsushita Electronics Corp
High pressure metal vapor discharge lamp

JPS5034871B1
(en)

1970-12-09
1975-11-12

DD105937A1
(en)

1973-09-06
1974-05-12

US3931536A
(en)

1974-07-15
1976-01-06
Gte Sylvania Incorporated
Efficiency arc discharge lamp

1977

1977-03-14
US
US05/777,149
patent/US4109175A/en
not_active
Expired – Lifetime

1977-03-15
FR
FR7707687A
patent/FR2344961A1/en
active
Granted

1977-03-17
GB
GB11369/77A
patent/GB1569366A/en
not_active
Expired

1977-03-17
DE
DE2711733A
patent/DE2711733C2/en
not_active
Expired

1977-03-18
CA
CA274,268A
patent/CA1064566A/en
not_active
Expired

Cited By (2)

* Cited by examiner, † Cited by third party

Publication number
Priority date
Publication date
Assignee
Title

GB2145557A
(en)

1983-08-13
1985-03-27
Emi Plc Thorn
Improvements in discharge lamps

US4771207A
(en)

1983-08-13
1988-09-13
Thorn Emi Plc
Discharge lamp assembly

Also Published As

Publication number
Publication date

DE2711733C2
(en)

1985-08-08

FR2344961A1
(en)

1977-10-14

FR2344961B1
(en)

1981-05-08

DE2711733A1
(en)

1977-09-29

US4109175A
(en)

1978-08-22

CA1064566A
(en)

1979-10-16

Información de contacto