US3390297A - Shield for hollow cathode lamps - Google Patents

Shield for hollow cathode lamps Download PDF

Info

Publication number
US3390297A
US3390297A US562145A US56214566A US3390297A US 3390297 A US3390297 A US 3390297A US 562145 A US562145 A US 562145A US 56214566 A US56214566 A US 56214566A US 3390297 A US3390297 A US 3390297A
Authority
US
United States
Prior art keywords
shield
cathode
lamp
hollow cathode
pins
Prior art date
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 - Lifetime
Application number
US562145A
Other languages
English (en)
Inventor
John W Vollmer
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.)
Applied Biosystems Inc
Original Assignee
Perkin Elmer 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.)
Filing date
Publication date
Application filed by Perkin Elmer Corp filed Critical Perkin Elmer Corp
Priority to US562145A priority Critical patent/US3390297A/en
Priority to DE19671589295 priority patent/DE1589295A1/de
Priority to GB30238/67A priority patent/GB1183114A/en
Priority to FR8927A priority patent/FR1538497A/fr
Priority to SE10236/67*A priority patent/SE343429B/xx
Priority to JP42042275A priority patent/JPS507472B1/ja
Application granted granted Critical
Publication of US3390297A publication Critical patent/US3390297A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J17/00—Gas-filled discharge tubes with solid cathode
    • H01J17/02—Details
    • H01J17/04—Electrodes; Screens
    • H01J17/06—Cathodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J17/00—Gas-filled discharge tubes with solid cathode
    • H01J17/02—Details
    • H01J17/04—Electrodes; Screens
    • H01J17/06—Cathodes
    • H01J17/066—Cold cathodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J17/00—Gas-filled discharge tubes with solid cathode
    • H01J17/38—Cold-cathode tubes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J17/00—Gas-filled discharge tubes with solid cathode
    • H01J17/38—Cold-cathode tubes
    • H01J17/40—Cold-cathode tubes with one cathode and one anode, e.g. glow tubes, tuning-indicator glow tubes, voltage-stabiliser tubes, voltage-indicator tubes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J61/00—Gas-discharge or vapour-discharge lamps
    • H01J61/92—Lamps with more than one main discharge path
    • H01J61/94—Paths producing light of different wavelengths, e.g. for simulating daylight
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2893/00—Discharge tubes and lamps
    • H01J2893/0064—Tubes with cold main electrodes (including cold cathodes)
    • H01J2893/0065—Electrode systems
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2893/00—Discharge tubes and lamps
    • H01J2893/0064—Tubes with cold main electrodes (including cold cathodes)
    • H01J2893/0065—Electrode systems
    • H01J2893/0066—Construction, material, support, protection and temperature regulation of electrodes; Electrode cups
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2893/00—Discharge tubes and lamps
    • H01J2893/0064—Tubes with cold main electrodes (including cold cathodes)
    • H01J2893/0065—Electrode systems
    • H01J2893/0067—Electrode assembly without control electrodes, e.g. including a screen

Definitions

  • the invention utilizes a generally cylindrical shell of insulating material partly surrounding the cathode so as to both restrict the volume of glowing vapor (thereby increasing its brightness) and blocking the sputtered material from coating other parts of the lamp (which coating tends to cause short circuits within the lamp).
  • the shell partially restricts the open end of the cathode so as to form an effective aperture smaller than the interior of the cathode.
  • This invention relates to hollow cathode lamps of the type used, for example, as atomic absorption radiation sources. More particularly this invention concerns improving such lamps by shielding the hollow cathode in such a manner as to increase the useful life and the practical available energy therefrom.
  • a source of radiation having high intensity in the spectral lines of the metal or metals being tested, is required.
  • One preferable source of such radiation comprises a discharge lamp in which the cathode is in the form of a hollow cylinder open at one end. At least the interior surfaces of this hollow cathode includes the one or more metals for which the emission spectrum is desired.
  • an electrical current is passed from an anode to this cathode (through a low pressure inert gas), the metal or metals will sputter from the cathode surface so as to form a cloud of substantially atomic particles.
  • shields according to the invention greatly reduce this coating action so as to eliminate such shorting as a major contributor to lamp failure. Shields according to the invention also lessen the rate of loss of'the emitting metal or metals from the interior of the hollow cathode, thereby improving another factor in the lamp life. Finally, shields according to the invention actually increase the intensity of the useful emission for a given electrical current density (this effect being quite marked with the form of the invention in which the open end of the hollow cathode is partly restricted by the shield, as will be seen hereinafter).
  • An object of the invention is the provision of a shield for the hollow cathode in a lamp which not only restricts the glow to the inside of the cathode, but substantially reduces the amount of material sputtered to the various other lamp parts, and increases the emission efiiciency of the lamp (even in comparison with hollow cathode lamps having other types of shielding of the hollow cathode).
  • FIG. 1 is a part elevation, part vertical section through one embodiment of the invention.
  • FIG. 2 is a similar view of a second embodiment of the invention.
  • FIG. 1 A relatively simple exemplary embodiment of the inventive hollow cathode shield is shown in FIG. 1, as incorporated in a more or less otherwise conventional hollow cathode lamp.
  • the conventional parts of this lamp will first be described.
  • Such a lamp comprises a closed envelope 10, formed by a main cylindrical (typically glass) tube 12, which has been closed at each end by, respectively, a stem assembly 14 and a transmitting window 16.
  • the stem assembly 14 supports a plurality of pins or rods, assumed (for exemplary purposes) to comprise four pins symmetrically arranged about the central longitudinal axis of the lamp (the pins therefore being in a square or diamond-shaped arrangement).
  • One of these pins, 15, is bent so as to form a portion 17 extending radially to the longitudinal central axis of tube 12, at which point it bends again so as to have a portion at 18 coincident with this axis.
  • Portion 18 supports the hollow cathode assembly 20.
  • Such cathode assembly comprises the hollow cathode cup proper 22, which includes material comprising the element or elements having the spectral lines desired. This material may, for example, be coated (as at 24) on the interior walls of the hollow cathode cup 22.
  • the hollow cathode 22 may comprise a cup-shaped insert which is press fit or otherwise secured within the cathode 22; or the hollow cathode 22 itself may be composed of the desired material.
  • the hollow cathode may be supported by an integral narrower portion 2% being crimped or press fit onto center pin portion 18.
  • An insulating base 30 is attached as by cementing to the stem assembly 14 end of the envelope 19.
  • a pair of short pins (of which only the one at 32 is seen in FIG. 1) are at the two vertices of the square or diamond adjacent to that of pin 15 (so that these short pins are diametrically opposite each other in the horizontal central plane of FIG. 1).
  • a horizontal, radially extending bar 34 is attached (as by welding) adjacent the right-hand ends of these short pins (only end 33 of pin 32 being visible in FIG. 1). The middle of the horizontal bar 34 is attached to the central bend 35 (between portions 17 and 18) of pin 15.
  • the two short pins and hori- Zontal bar 34 thereby form a relatively rigid tripod ar- 3 rangement with bent pin 15.
  • a lower conducting pin 36 (diametrically opposite bent pin in the central vertical plane) supports a slightly bent, rod-like anode 33.
  • the electrically connecting pins (in this case 15 and 36) will be connected to electrical leads 42 and 46, respectively, as at 48 and 4-4, respectively.
  • Leads 42 and 46 may emerge from base as strands of a cable 4-8, terminating in an electrical plug connector 4-9.
  • Leads 42 and 46 are preferably embedded in slack condition in an 'nsulating tiller 5% within an outer hard casing 52 forming the base
  • a strain release 54 may be provided at emerging point of the cable 3-8 from the casing 52.
  • a hollow cathode lamp of this generally conventional type (assumed to be without the shield of the invention, indicated at 63) operates as follows.
  • the opposite sides of an electrical power supply are connected (by means of plug 49, cable 48, leads 42. and 46, pins 15 and 36) to the hollow cathode 22 and the anode 38.
  • Typical operating currents are in the range from 10 to milliarnpercs, and typical operating voltages are between 150 v. to 300 v.
  • a cloud of small excited particles (at least some of which are atoms of the desired element) is thereby formed from a material sputtered from the hollow cathode at its elevated temperature within the electrical field. Relatively high intensity emission at the spectral lines characteristic of the desired metallic element is therefore generated (along with other radiation), so as to pass through end window 16 to be used in the, say, atomic absorption spectrometer.
  • the material condensing is metallic, even a relatively thin coating thereof is a relatively good electrical conductor. Therefore even a very thin coating on the interior surface 58 of the stem assembly 14 can cause a substantial short (directly or indirectly) between the electrically negative pin 35 and the anode pin 35.
  • Use of insulation is only partially effective. Insulation in the form of sleeves or the like become coated with condensed metal vapor so that electrical paths are established along their entire surface from one end to the other. Only if the enclosing insulation is substantially vapor-tight for its entire length (including at its two ends) will the insulation be effective. In general it is extremely difiicult to maintain such vapor-tight connections between dissimilar materials. Further, since the cathode and anode themselves must be free of.
  • Insulating caps such as shown at 51 and 53 (on the base or" bent cathode pin 15 and short pin 32, respectively) at least inhibit the formation of an electrically conducting path between the (coated) stern assembly and these pins during use. Specifically, these caps create an undercut or re-entrant gap, as at 55 and 57 respectively, between themselves and the adjacent surface of the stem assembly (i.e., thickened mounds 59); this gap is relatively inaccessible to the metallic vapor and therefore tends to maintain a break in the continuity of any coating.
  • cathode shield which greatly reduces the rate of escape of the vapor and therefore the rate at which a coating of condensed vapor is formed, is shown generally at till.
  • This shield is cupsbaped and generally conforms to the exterior of the cathode 22.
  • the shield 69 has cylindrical walls which extend substantially beyond the open end of the hollow cathode to form a hood portion, as may be seen at 62. Additionally this open end part of the shield has thinner walls than the remaining part so as to leave a recess or gap (:4, between the parts of the cathode 22 near its opening and the adjacent portions of the shield.
  • Shield 69 may be mounted by the provision of an aperture in closed end 6-5, which surrounds the outer cylindrical surface of narrower portion 26 of the cathode.
  • a press fit retaining washer 63 may be used to assure adequate support of the shield.
  • Shield 66 may be integrally molded piece of pressed alumina or other suitable refractory electrically insulating material. T.e hood or wall extensions 62 will intercept a substantial portion of the material forming the interior of the cathode which would otherwise sputter away from the cathode vic :ity and eventually condense on the interior parts of the tube.
  • FIG. 2 A different embodiment of the invention is shown in FIG. 2. Since many of the conventional parts of the second embodiment may be the same as those of the already described one, such similar parts are indicated by use of primed numbers corresponding to the unprimed numbers of FIG. 1.
  • envelope 10, tube 12, stem assembly 14', window 16', the hollow cathode 2t) and its component parts 22'26', and insulating base 39' may all be substantially identical to the corresponding parts of FIG. 1.
  • Hollow cathode 20' may be supported on a central pin portion 18' extending along the longitudinal center line of the tube 12'. This portion 18' may be formed by two right angle bends (forming intermediate radially extending pin portion 17') of a pin 15', in a manner similar to pin 15 and portions 17 and 18 in FIG.
  • both pin 15 and its unseen paired pin may be short (like pin 32 in FIG. 1) and support at their ends a transverse bar (like 34 in FIG. 1) which in turn rigidly supports at its center a longitudinally extending central pin acting as the cathode support pin 13.
  • both pins perform the additional function of assisting in supporting the different form of the shield of FIG. 2.
  • the shield 160 of FIG. 2 comprises a main cylindrical body portion 161, which has a partly closed end portion or hood 162 (at the right in FIG. 2) which has a central aperture at 164.
  • the end or hood portion 162 is recessed at its periphery so as to form an annular shoulder 166.
  • a hold-down plate 170 has a relatively large central aperture fitting this shoulder 166, and also has smaller upper and lower apertures so as to receive the ends 133, 135 of pins 134 and 136, respectively.
  • Retaining washers 1'72 and .176 snugly engage ends 133 and 135 of the pins so as to secure the hold-down plate 170 against movement to the right.
  • Disc 180 also has smaller apertures (as at 182, 186) so as to allow relatively snug passage of upper and lower pins 132 and 136 (additional similar apertures being provided if additional pins are present).
  • the peiipheral edge 188 of disc 180 is preferably of substantially the same diameter and circular configuration as the interior surface 156 of tube 12, thereby providing additional mechanical support for not only the disc 180 but also pins 134, 136 and shield 160.
  • the FIG. 2 shield 160 is preferably made of a nonconductive material (which for example may also be molded alumina).
  • Holddown plate 170 may be the same or another nonconductive material (and in fact may be integrally formed with shield 160 if desired).
  • An annular gap, such as at 192, is preferably maintained between the exterior of the cathode and the interior wall of the shield 16!) to allow for thermal expansion of the cathode during use.
  • the corner edge 165 of end portion 162 of the shield acts as a baffle, so that the outer or right-hand surface 167 of the hood portion .162 is not fully coated with metal vapor even after substantial use of the lamp.
  • the potential electrical path to the plate 170 (and ultimately to the anode 133 and/ or 135) is therefore not established, so that electrical isolation of the cathode and anode is maintained.
  • the large disc 130 (which may for example be mica), not only provides mechanical support to the various elements, but also inhibits the formation of any condensation of sputtered vapor in the volume enclosed by stem assembly 14', the left-hand interior surfaces of tube 12 and the disc 180 itself.
  • Disc 1S0 therefore acts as an auxiliary shield from sputtered material for the parts within this volume.
  • Substantially identical upper and lower sleeves 204 and 206 may be provided about pins 134 and 136 respectively, which sleeves may provide additional mechanical support for the pins and disc 180 as well as electrical insulation for the pins.
  • the lefthand ends of these sleeves meet the adjacent surfaces of the supporting mounds 59 of the stem assembly so as to leave undercut or substantially re-entrant gaps 203, 205 (similar to gaps 55, 57 of FIG. 1).
  • the pins 134, 136 (at least one of which acts as the anode) are protected from becoming electrically connected to the stem assembly 14- by the coating action of the vapor; in the FIG. 1 form, the electrically negative (cathode) pin 15 (and the connected short pin 32 and the other, not shown, short pin) were insulated by a similar gap from being electrically connected to the coating on the stem assembly.
  • the gap accomplishes the same general result either way, namely, insulating the cathode and the electrically negative pins on the one hand from the anode and the electrically positive pins on the other hand (by avoiding a conductive path from one across the stem assembly to the other).
  • the shield of FIG. 2 thus inhibits the glow which otherwise occurs about the exterior surfaces of the cathode 2t); and the hood portion 162 greatly reduces the amount of sputtered material (from the interior leaving the open front end of the cathode) which otherwise would condense upon the various other interior parts of the lamp.
  • the shield of FIG. 2 restricts the size of the opening of the interior of the hollow cathode 22 in that aperture 164 is substantially smaller than the cathode interior diameter. This restriction improves the lamp performance in a number of ways.
  • the brightness ie., the radiant flux density per unit cross-sectional area
  • the smaller cross-sectional of aperture 164 also improves (both theoretically and practically) the efficiency of collection and beam formation of this energy.
  • the volume bounded by the interior of the hollow cathode and the inner surfaces of the restricting flanges or hood 162 of the shield is relatively large, the total intensity of the glow remains quite large. In other words, the effect of the shield with the restricted opening is to increase the effective concentration of the radiation without diminishing its total intensity, thereby giving a brighter source.
  • the restriction so reduces the sputtering losses that a given lamp with the shield may be run at substantially higher currents than the same lamp without the shield, thus further increasing the total intensity (and therefore the brightness) of the shielded lamp.
  • Another advantageous effect of the restricted opening at 164 is to cause the active material of the hollow cathode lamp (ie., the interior layer 24') to assume during use a rounded shape approximating that of a moderately eccentric ellipsoid (i.e., departing only moderately from a spherical surface).
  • the restricted opening of the shield 1160 actually improves the inherent efiiciency of the hollow cathode itself, because of this shaping tendency.
  • a hollow cathode lamp using a restricted opening shield substantially conforming to that of FIGQZ yields a further unexpected advantage when used as an atomic absorption spectroscopic source.
  • the intensity of the atom line radiation i.e., radiation corresponding to the wavelength emitted and absorbed by the metal in its atomic state
  • the ion line radiation at the wavelength emitted or absorbed by the metal in its ionized state
  • the reason for this enhancement of the ratio of the desired (atomic line) radiation relative to the undesired (ion line) radiation is not fully understood.
  • such restricted opening shielded cathode lamps do outperform conventional lamps in typical atomic absorption spectrometers, where the measurement is made at the .atom line wavelength and the ion line radiation is nonabsorbing interfering signal.
  • Shields generally conforming to each of the embodiments of FIG. 1 and FIG. 2 have been successfully constructed and tested.
  • a shield conforming generally to that shown at 68- in FIG. 1 had an internal diameter of its main body portion just larger than the external diameter of the hollow cathode in which it was to be used (namely, .460 and .440 inch, respectively).
  • the center walls defining the open end or hood portion 62 extended about of an inch beyond the open end of the cathode itself.
  • the recess at 64 provided an additional radial clearance of about .01 to .02 of an inch, and was formed by continuing the thin wall portion 62 for a total length of about of an inch (so that recess 64 had a longitudinal length of about A; of an inch before being opposite the open end of the cathode).
  • a magnesium (at 24) lamp incorporating such a shield was compared with an unshielded, otherwise substantially identical magnesium lamp.
  • the unshielded magnesium lamp contained a coating on the interior wall of tube 12 from the stem 14 to within about an inch of window 16 (a total longitudinal distance of about 5 inches of the sixinch length of tube 12.).
  • the shielded lamp of the invention had only a quite light ring of magnesium coating on the glass tube in the area generally indicated at 56, the ring being only approximately one and a quarter inch wide (being spaced therefore about one and one-half inches from the stem and about 3% inches from the window end of tube 12.
  • the sputtered coating on the glass increased to less than a two-inch wide band and was somewhat thicker.
  • the interior portion of the shield i.e., the inside surface 63 of the hood or end walls 62
  • the radially narrow and relatively deep (in the longitudinal direction) recess 64 was successful in creating a gap in the coating on the interior of the shield and the cathode itself, since no tendency to short the shield to the cathode occurred.
  • the other version of this type of shield was generally similar, except that instead of a recessed shoulder portion and separate hold-down plate, it had integrally formed at the right-hand end a relatively extensive flangelike portion, conforming both in general dimensions and function with the hold-down plate 170.
  • the exterior diameter of both of these forms of the shield 160 was .585 inch, so that the internal diameter was .485 inch.
  • the restricting aperture 164 had a diameter of .187 7 inch, the unrestricted internal diameter of the hollow cathode being about twice this of an inch).
  • the mica disc 18-0 was approximately 1 /2 inches from the stem assembly base 14, and surrounded the shield 160 at approximately its longitudinal center.
  • the right-hand, apertured end 1162. of the shield was therefore somewhat less than one-half inch on the other side of the disc 180.
  • shields of both the FIG. 1 and the FIG. 2 types achieve the objective of increasing the useful life of the lamp and/or increasing the usable intensity (and brightness) of the lamp.
  • shields of either type may be used in various hollow cathode lamps, such shields are especially useful for hollow cathode lamps in which the sputtered active -metals include the more violently sputtering and lower boiling point metals (such as, for example, magnesium, cadmium, selenium, and the like).
  • a hollow shield of refractory, electrically insulating material generally surrounding and conforming to the general shape of said hollow cathode
  • said shield comprising a hood portion, extending beyond and at least partially surrounding the open end of said cup-shaped hollow cathode;
  • said hood portion being of such shape and in such relationship with said cathode open end as to intercept most of the sputtered material which otherwise would escape from said open end;
  • the part of the hollow cathode defining its open end and the hood portion of said shield closely adjacent thereto are of such size and shape as to cause a continuous gap in any deposited metal coating therebetween,
  • said hood portion of said shield comprises a generally cylindrical portion extending substantially beyond the open end of said cathode
  • said hood portion of said shield is of such size and shape relative to the adjacent part of said cathode as to be spaced apart therefrom to leave a continuous gap therebetween,
  • said hood portion of said shield comprises an end wall portion extending radially inwardly, beyond but near said cathode open end, so as to partially restrict the opening therein, whereby a major fraction of the sputtered material escaping from said cathode open end is intercepted by and deposited on said radially extending end wall portion.
  • said shield is supported by mounting means
  • said mounting means comprising, at least in part, an
  • said auxiliary shield is in the form of an extensive disc

Landscapes

  • Discharge Lamp (AREA)
  • Vessels And Coating Films For Discharge Lamps (AREA)
  • Spectrometry And Color Measurement (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)
US562145A 1966-07-01 1966-07-01 Shield for hollow cathode lamps Expired - Lifetime US3390297A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
US562145A US3390297A (en) 1966-07-01 1966-07-01 Shield for hollow cathode lamps
DE19671589295 DE1589295A1 (de) 1966-07-01 1967-06-23 Abschirmung fuer Hohlkathodenlampen
GB30238/67A GB1183114A (en) 1966-07-01 1967-06-30 Hollow Cathode Lamps
FR8927A FR1538497A (fr) 1966-07-01 1967-06-30 Lampe à cathode creuse
SE10236/67*A SE343429B (cs) 1966-07-01 1967-06-30
JP42042275A JPS507472B1 (cs) 1966-07-01 1967-07-01

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US562145A US3390297A (en) 1966-07-01 1966-07-01 Shield for hollow cathode lamps

Publications (1)

Publication Number Publication Date
US3390297A true US3390297A (en) 1968-06-25

Family

ID=24244988

Family Applications (1)

Application Number Title Priority Date Filing Date
US562145A Expired - Lifetime US3390297A (en) 1966-07-01 1966-07-01 Shield for hollow cathode lamps

Country Status (6)

Country Link
US (1) US3390297A (cs)
JP (1) JPS507472B1 (cs)
DE (1) DE1589295A1 (cs)
FR (1) FR1538497A (cs)
GB (1) GB1183114A (cs)
SE (1) SE343429B (cs)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3474280A (en) * 1967-09-14 1969-10-21 Perkin Elmer Corp Lamps using spherical cathodes
US3516009A (en) * 1967-07-27 1970-06-02 Perkin Elmer Corp High stability laser
US3582818A (en) * 1968-03-21 1971-06-01 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Gas laser having the discharge tube connection to the cathode by a conduit with a constrictive orifice
US3585436A (en) * 1969-04-23 1971-06-15 Philips Corp Low-pressure gas-discharge lamp for producing resonance radiation
US3934167A (en) * 1970-04-24 1976-01-20 U.S. Philips Corporation Gaseous electric discharge tube having a coaxial, hollow cathode structure
US4100446A (en) * 1973-06-01 1978-07-11 Hitachi, Ltd. Light source lamp with particular envelope structure to accommodate external magnets
DE3107522A1 (de) * 1981-02-27 1982-11-04 Siemens AG, 1000 Berlin und 8000 München "gasentladungsvorrichtung fuer ein bildanzeigegeraet"
US4461970A (en) * 1981-11-25 1984-07-24 General Electric Company Shielded hollow cathode electrode for fluorescent lamp
EP0732719A1 (en) 1995-03-14 1996-09-18 Osram Sylvania Inc. Discharge device having cathode with micro hollow array

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE435332B (sv) * 1979-11-07 1984-09-17 Lumalampan Ab Katodenhet for lysror
US4795942A (en) * 1987-04-27 1989-01-03 Westinghouse Electric Corp. Hollow cathode discharge device with front shield

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2177714A (en) * 1936-10-27 1939-10-31 Gen Electric Gaseous electric discharge lamp device
US2431226A (en) * 1943-02-11 1947-11-18 Westinghouse Electric Corp Low-pressure gap device
US2433809A (en) * 1947-02-01 1947-12-30 Sylvania Electric Prod Crater lamp
US2592556A (en) * 1947-09-25 1952-04-15 Kenneth J Germeshausen Gaseous-discharge device
US3264511A (en) * 1963-06-20 1966-08-02 Westinghouse Electric Corp Glow discharge device

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2177714A (en) * 1936-10-27 1939-10-31 Gen Electric Gaseous electric discharge lamp device
US2431226A (en) * 1943-02-11 1947-11-18 Westinghouse Electric Corp Low-pressure gap device
US2433809A (en) * 1947-02-01 1947-12-30 Sylvania Electric Prod Crater lamp
US2592556A (en) * 1947-09-25 1952-04-15 Kenneth J Germeshausen Gaseous-discharge device
US3264511A (en) * 1963-06-20 1966-08-02 Westinghouse Electric Corp Glow discharge device

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3516009A (en) * 1967-07-27 1970-06-02 Perkin Elmer Corp High stability laser
US3474280A (en) * 1967-09-14 1969-10-21 Perkin Elmer Corp Lamps using spherical cathodes
US3582818A (en) * 1968-03-21 1971-06-01 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Gas laser having the discharge tube connection to the cathode by a conduit with a constrictive orifice
US3585436A (en) * 1969-04-23 1971-06-15 Philips Corp Low-pressure gas-discharge lamp for producing resonance radiation
US3934167A (en) * 1970-04-24 1976-01-20 U.S. Philips Corporation Gaseous electric discharge tube having a coaxial, hollow cathode structure
US4100446A (en) * 1973-06-01 1978-07-11 Hitachi, Ltd. Light source lamp with particular envelope structure to accommodate external magnets
DE3107522A1 (de) * 1981-02-27 1982-11-04 Siemens AG, 1000 Berlin und 8000 München "gasentladungsvorrichtung fuer ein bildanzeigegeraet"
US4461970A (en) * 1981-11-25 1984-07-24 General Electric Company Shielded hollow cathode electrode for fluorescent lamp
EP0732719A1 (en) 1995-03-14 1996-09-18 Osram Sylvania Inc. Discharge device having cathode with micro hollow array
US5686789A (en) * 1995-03-14 1997-11-11 Osram Sylvania Inc. Discharge device having cathode with micro hollow array
US5939829A (en) * 1995-03-14 1999-08-17 Osram Sylvania, Inc. Discharge device having cathode with micro hollow array
US6072273A (en) * 1995-03-14 2000-06-06 Osram Sylvania Inc. Discharge device having cathode with micro hollow array
US6346770B1 (en) 1995-03-14 2002-02-12 Osram Sylvania, Inc. Discharge device having cathode with micro hollow array
US6518692B2 (en) 1995-03-14 2003-02-11 Old Dominion University Discharge device having cathode with micro hollow array

Also Published As

Publication number Publication date
FR1538497A (fr) 1968-09-06
SE343429B (cs) 1972-03-06
GB1183114A (en) 1970-03-04
DE1589295A1 (de) 1970-03-05
JPS507472B1 (cs) 1975-03-26

Similar Documents

Publication Publication Date Title
US5511104A (en) X-ray tube
US3390297A (en) Shield for hollow cathode lamps
US3121184A (en) Discharge lamp with cathode shields
US2467687A (en) High-pressure discharge lamp
US2549355A (en) Fluorescent lamp
GB1329228A (en) Electron beam apparatus
JP5490135B2 (ja) 重水素ランプにおけるカソード遮蔽部材
US2032179A (en) Oxide coated cathode for heavy duty service
US1874753A (en) Controlled arc discharge apparatus
US1834251A (en) Electrical discharge device
US5483121A (en) Hollow cathode discharge tube
JP2913186B2 (ja) イオン源装置
US2714687A (en) High pressure mercury vapor electric discharge lamps
US3013175A (en) High output discharge lamp
US4698550A (en) Hollow cathode lamp
US3855491A (en) Hollow cathode discharge lamp for generating radiation characteristic of the gas fill within the envelope
US4356428A (en) Lighting system
US2048023A (en) Dual purpose thermionic tube
US3005123A (en) Electron gun construction
US3069581A (en) Low pressure discharge lamp
US1991479A (en) Glow lamp
US1632080A (en) Electric discharge device
US2512282A (en) Electric discharge lamp
US1954420A (en) Glowlamp
US2748308A (en) Low-pressure arc-discharge tube supplied with direct current