US2846591A - Safety circuit arrangment for multiplier tubes - Google Patents

Safety circuit arrangment for multiplier tubes Download PDF

Info

Publication number
US2846591A
US2846591A US587621A US58762156A US2846591A US 2846591 A US2846591 A US 2846591A US 587621 A US587621 A US 587621A US 58762156 A US58762156 A US 58762156A US 2846591 A US2846591 A US 2846591A
Authority
US
United States
Prior art keywords
voltage
electrode
current
value
anode
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
US587621A
Other languages
English (en)
Inventor
Valeton Josue Jean Philippe
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.)
US Philips Corp
North American Philips Co Inc
Original Assignee
US Philips 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 US Philips Corp filed Critical US Philips Corp
Application granted granted Critical
Publication of US2846591A publication Critical patent/US2846591A/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
    • H01J43/00—Secondary-emission tubes; Electron-multiplier tubes
    • H01J43/04—Electron multipliers
    • H01J43/30—Circuit arrangements not adapted to a particular application of the tube and not otherwise provided for
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
    • H03F1/52—Circuit arrangements for protecting such amplifiers
    • H03F1/54—Circuit arrangements for protecting such amplifiers with tubes only
    • H03F1/548—Protection of anode or grid circuit against overload

Definitions

  • multiplier tube amplifiers As an example of the use of multiplier tube amplifiers mention may be u ade of light-spot scanners for stationary pictures or for cinematographic films.
  • the amplification of these amplifiers is controlled by hand or automatically, when dark and bright pictures, for example diapositives or filmparts, are scanned in succession.
  • This amplification control is usually produced by varying the voltage across a few multiplier stages which are chosen within the middle-range of the series of stages.
  • the current in the last stages or in the anode circuit may become very large and may be likely to dam age the multiplier tube because of the fact that the settingback of the amplification-control always becomes operative with some time delay.
  • the invention relates to safety circuit arrangements for a multiplier tube. It is an object of the invention to provide a circuit arrangement, by which the tube is automatically protected against overload which may be due to overdriving.
  • At least one secondary emission electrode of the tube is connected to the cathode of a diode and also, through aresistance, to a point of considerably lower potential, the anode of the diode being connected to a terminal of a voltage-supply source, which terminal is positive with respect to the cathode of the tube, so that the current flowing through the diode is reduced by the value of the current from the said electrode, and that, when the current from the electrode exceeds a predetermined value, the diode is cut off and the voltage across the resistance is increased.
  • Fig. 1 shows the electron multiplication characteristic curve of a secondaryemission electrode
  • Fig. 2 shows the circuit arrangement of one embodiment of the circuit in accordance with the invention.
  • the embodiment shown in Fig. 2 contains a multiplier tube 1 having a photo-cathode 2, siX secondary emission electrodes 3, 4, 5, 6, 7 and 8 and an anode 9.
  • the anode 9 is connected to the positive terminal of a voltage supply source 11 of, for example, 600 volts, the ne ative terminal of which is directly connected to the photo cathcde Z.
  • the anode 9 is connected to an output terminal 13.
  • a Voltage divider is connected between the positive terminal of the source 11 and the cathode 2.
  • This voltage divider comprises a resistor 14 of fixed value, two rheostats 15 and 16 and four voltage stabilizing gas-discharge tubes 17, 13, 19 and 20.
  • the electrodes 3 to 8 are each connected to a suitable junction of two successive parts of the voltage divider.
  • the electrode 7 is connected to the junction of the discharge tubes 13 and 19 through a diode 21, for example a germanium diode, the anode of which is connected to the said point.
  • the electrode 7 is also connected, through a resistor 22, to the junction of the rheostat 16 and the discharge tube 17, and also to the electrode S.
  • the curve shown in Fig. l is a typical example of the electron multiplication characteristic of a secondary emission electrode. It will be seen that the multiplication factor M gradually increases with increase of the voltage 1,, between this electrode and the preceding electrode and that, when this voltage reaches a pre-determined value (for example volts), the multiplication factor M increases in a lesser degree and even decreases at still higher voltage (for example volts), a state of saturation being reached.
  • a pre-determined value for example volts
  • the electron multiplication on the electrode 3 can only slightly increase and decreases again at even higher voltages, so that the overall amplification of the circuit arrangement decreases.
  • the circuit arrangement described may, for example, be used for television image-viewing purposes, as an amplifier in a light-spot scanner for stationary pictures or for cine matographic films.
  • the resistor 22 passes a current which is determined by the value of this resistor and by the voltage across the discharge tubes 17 and 13.
  • the diode 21 passes a current which is equal to the current through the resistor 22 reduced by the value of the current from the electrode 7. So long as the diode is conductive, the voltage on the electrode 7 remains substantially equal to the stabilized voltage at the junction of the discharge tubes 18 and 19.
  • the value of the resist-or 22 is chosen such that, at a voltage equal to that of the discharge tubes 17 and 18, it just passes a current the value of which is considered to be the permissible maximum for the electrode 7.
  • the current to the electrode 7 reaches this value, no current flows any more through the diode 21. Consequently, this diode is cut off, so that the voltage on the electrode 7 is no longer stabilized.
  • this voltage increases with increase in the current passing through the resistor 22 and the amplification on the electrode '7 slightly increases with the voltage and subsequently decreases in accordance with the curve shown in Fig. 1.
  • the amplification on the next following electrode 8 decreases considerably so that the overall amplification of the tube decreases and the current in the stages '78 and S-9 and in the anode circuit is held at a safe level.
  • the operation of the circuit arrangement described amounts to a high degree of negative feedback which is only produced in the resistor 22 when a pre-determined current level is exceeded. This negative feedback is higher as the value of the resistor 22 increases.
  • a safety circuit for an electron multiplier tube having a cathode, an anode, and at least one secondary emission electrode comprising a voltage supply source having negative and positive terminals respectively connected to said cathode and anode and having a first intermediate voltage terminal and a second voltage terminal which has a negative polarity with respect to said first intermediate voltage terminal, a rectifier having an anode connected to said first intermediate voltage terminal and having a cathode connected to said secondary emission electrode, and a resistance connected between said secondary emission electrode and said second voltage terminal, said resistance having a value such that said rectifier is conductive during normal operation of said tube and becomes nonconductive when the current from said secondary emission electrode exceeds a predetermined value.
  • a circuit as claimed in claim 2 including means for stabilizing the voltages at said second and third voltage terminal
  • a circuit as claimed in claim 4 including means for stabilizing the voltages at said second and third voltage terminals with respect to the voltage at said first voltage terminal.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Photometry And Measurement Of Optical Pulse Characteristics (AREA)
  • Amplifiers (AREA)
  • Details Of Television Scanning (AREA)
US587621A 1955-06-11 1956-05-28 Safety circuit arrangment for multiplier tubes Expired - Lifetime US2846591A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL791375X 1955-06-11

Publications (1)

Publication Number Publication Date
US2846591A true US2846591A (en) 1958-08-05

Family

ID=19834420

Family Applications (1)

Application Number Title Priority Date Filing Date
US587621A Expired - Lifetime US2846591A (en) 1955-06-11 1956-05-28 Safety circuit arrangment for multiplier tubes

Country Status (5)

Country Link
US (1) US2846591A (enrdf_load_stackoverflow)
DE (1) DE1026884B (enrdf_load_stackoverflow)
FR (1) FR1153981A (enrdf_load_stackoverflow)
GB (1) GB791375A (enrdf_load_stackoverflow)
NL (1) NL104002C (enrdf_load_stackoverflow)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3050632A (en) * 1959-04-21 1962-08-21 Litton Systems Inc Photo-transducer signal compressor
US3155831A (en) * 1960-02-23 1964-11-03 Bruce Peebles & Co Ltd Protective system for photoresponsive units
US3227875A (en) * 1961-05-04 1966-01-04 Eberline Instr Corp Gamma dose rate meter utilizing a scintillation detector
US3296538A (en) * 1963-04-04 1967-01-03 Vincent D Stabilito Photomultiplier amplifier and power supply
US3543095A (en) * 1968-11-05 1970-11-24 Us Navy Photocathode protection circuit
US3560755A (en) * 1968-03-29 1971-02-02 Campagnie Generale D Electrici High sensitivity radiation detector

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2516338A1 (fr) * 1981-11-09 1983-05-13 Tardivet Marc Dispositif de commande d'exposition pour ensemble radiologique

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB478153A (en) * 1936-11-13 1938-01-13 Gen Electric Co Ltd Improvements in or relating to circuits including secondary emission electron multipliers
US2160797A (en) * 1936-11-20 1939-05-30 Bell Telephone Labor Inc Electron discharge apparatus

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB478153A (en) * 1936-11-13 1938-01-13 Gen Electric Co Ltd Improvements in or relating to circuits including secondary emission electron multipliers
US2160797A (en) * 1936-11-20 1939-05-30 Bell Telephone Labor Inc Electron discharge apparatus
US2160798A (en) * 1936-11-20 1939-05-30 Bell Telephone Labor Inc Electron discharge apparatus

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3050632A (en) * 1959-04-21 1962-08-21 Litton Systems Inc Photo-transducer signal compressor
US3155831A (en) * 1960-02-23 1964-11-03 Bruce Peebles & Co Ltd Protective system for photoresponsive units
US3227875A (en) * 1961-05-04 1966-01-04 Eberline Instr Corp Gamma dose rate meter utilizing a scintillation detector
US3296538A (en) * 1963-04-04 1967-01-03 Vincent D Stabilito Photomultiplier amplifier and power supply
US3560755A (en) * 1968-03-29 1971-02-02 Campagnie Generale D Electrici High sensitivity radiation detector
US3543095A (en) * 1968-11-05 1970-11-24 Us Navy Photocathode protection circuit

Also Published As

Publication number Publication date
NL104002C (enrdf_load_stackoverflow)
FR1153981A (fr) 1958-03-31
GB791375A (en) 1958-02-26
DE1026884B (de) 1958-03-27

Similar Documents

Publication Publication Date Title
US2434929A (en) Radio receiver circuits
US2846591A (en) Safety circuit arrangment for multiplier tubes
US3694659A (en) Automatic control circuit for image intensifier
US3027421A (en) Circuit arrangement for automatically adjusting the brightness and the contrast in atelevision receiver
US2206123A (en) Power supply device
US2777092A (en) Transistor triggering circuit
US4100407A (en) Photoelectric conversion circuit
US2509742A (en) Voltage limiting circuit
US2579816A (en) Voltage regulator
EP0033574B1 (en) Electrical power supply arrangement for image intensifier tubes and combination thereof with an image intensifier tube
US3710148A (en) Ripple eliminating circuit
US4217525A (en) Spot killer circuit
US3848123A (en) Automatic brightness control for image intensifier tube
GB840288A (en) Improvements in or relating to electric circuits including electron discharge devices having at least one secondary emissive electrode
US3321629A (en) Dynode control circuit for a photomultiplier tube using cascaded transistors
US2431511A (en) Signal level control system
US2730615A (en) Circuit-arrangement for reducing pulse interference in radio receivers
US3712999A (en) Control-circuit for a deflection circuit of a display arrangement
US3585299A (en) Picture display arrangement provided with a display tube
US3121199A (en) Virtual-earth amplifiers
US2817041A (en) Control circuits for cathode ray tubes
US2796531A (en) Gain stabilizing circuit for electron multiplier phototubes
US2516556A (en) Voltage control circuits
US3202919A (en) Electric circuit for producing an output pulse of leading edge substantially coincident with the trailing edge of an input pulse
US2123639A (en) Amplifying system