Photomultiplier tube having a transmission strip line photocathode and system for use therewith

• US 4,853,595 A
• Filed: 08/31/1987
• Issued: 08/01/1989
• Est. Priority Date: 08/31/1987
• Status: Expired due to Term

• Current Assignee: Ardie D. Walser, Robert R. Alfano
• Original Assignee: Ardie D. Walser, Robert R. Alfano
• Inventors: Alfano, Robert R., Walser, Ardie D.
• Primary Examiner(s): Wieder, Kenneth
• Application Number:
  US07/091,123
• Time in Patent Office: 701 Days
• Field of Search: 313/527, 313/529, 313/530, 313/532, 313/533, 313/537, 313/541, 313/542, 250/213 VT, 250/207
• US Class Current: 313/532
• CPC Class Codes: G01N 21/6408 with measurement of decay time, time resolved fluorescence
• CPC Class Codes: H01J 43/04 Electron multipliers if forming part of electron gun H01J3/023

Abstract

A photomultiplier tube which may be used in time resolving a luminiscence profile emitted from a sample with picosecond resolution using short (picosecond) electrical pulses as a probe and in time resolving an electrical pulse profile produced by fast electronic or optoelectronic devices with femtosecond resolution, using short (femtosecond) laser pulses as the probe is disclosed. The photomultiplier tube includes a photocathode for receiving light and producing emission of electrons in proportion to the intensity of the light, said photocathode having a transmission strip line configuration, accellerating means for accellerating electrons emitted by said photocathode, electron multiplication means for performing electron multiplication on the electrons emitted from the accellerating means, anode means for receiving electrons from the electron multiplication means and producing an analog electrical signal output, means for causing electrons emitted by the photocathode to move through the accellerating means and the electron multiplication means and then impinge on the anode means, and means connected to said photocathode for receiving an ultrafast voltage signal.

Claims

1. A photomultiplier tube comprising a housing having therein:

a. a photocathode for receiving light and producing emission of electrons in proportion to the intensity of the light,

b. accellerating means for accellerating electrons received from the photocathode,

c. means connected to the photocathode for receiving a voltage signal, the voltage signal passing through the photocathode and negatively biasing the photocathode relative to the accellerating means so as to cause electrons emitted by the photocathode to be accellerated to the accellerating means,

d. electron multiplication means for performing electron multiplication on electrons received from the accellerating means,

e. anode means for producing an analog electrical signal output of electrons received from the electron multiplication means, and

f. means coupling the accellerating means, the electrons multiplication means and the anode means to a high voltage source for negatively biasing the accellerating means relative to the electron multiplication means and for negatively biasing the electron multiplication means relative to the anode means so as to cause electrons at the accellerating means to be moved to the electron multiplication means and then from the electron multiplication means to the anode means.

2. A photomultiplier tube comprising a housing having therein:

a. a photocathode for receiving light and producing emission of electrons in proportion to the intensity of the light, the photocathode being in a transmission line configuration and having an input side and an output side,

b. accellerating means for accellerating electrons emitted by the photocathode,

c. electron multiplication means for performing electron multiplication on the electrons emitted from the accellerating means,

d. anode means for receiving electrons from the electron multiplication means and producing an analog electrical signal output,

e. means for causing electrons emitted by the photocathode to move through the accellerating means and the electron multiplication means and then impinge on the anode means,

f. means connected to the photocathode for receiving and transmitting out an ultrafast voltage signal, and

g. a variable aperture on the input side of the photocathode.

3. The photomultiplier tube of claim 2 and wherein the photocathode is a microstrip line.

4. The photomultiplier tube of claim 2 and wherein the photocathode is slot line.

5. The photomultiplier tube of claim 2 and wherein the photocathode is a coplanar waveguide.

6. The photomultiplier tube of claim 2 and wherein the photocathode is a coplanar strip.

7. The photomultiplier tube of claim 2 and wherein said means connected to said photocathode comprises high speed stripline launchers having 18 GHZ or 40 GHZ bandwidth.

8. The photomultiplier tube of claim 2 and wherein the variable aperture size is from about 5.0 um to 2 mm.

9. The photomultiplier tube of claim 2 and wherein the photocathode includes a photoconductive material selected from the group consisting of AG--O--Cs, Sb--Cs, Bialkali (Sb--rb--Cs₁), multialkali (S-20) and Ga--As--O--Cs.

13. The photomultiplier tube of claim 2 and wherein said photocathode comprises a substrate of dielectric material, a layer of photoconductive material on top of said substrate and a layer of conductive material below said substrate.

14. The photomultiplier tube of claim 13 and wherein said dielectric is glass and said conductive material is gold or copper.

15. The photomultiplier tube of claim 2 and wherein the aperture varies in diameter from 20 μ

m to 200 μ

m.

16. The photomultiplier tube of claim 2 and wherein the accellerating means is a mesh.

17. The photomultiplier tube of claim 2 and wherein the electron multiplication means is a dynode chain.

18. The photomultiplier tube of claim 2 and wherein the means for moving electrons is a high voltage.

10. A system for time resolving a voltage pulse from a test device comprising:

a. means for generating a pulse of light,

b. means for splitting the pulse of light into first and second beam paths,

c. a photomultiplier tube disposed along the first beam path, said photomultiplier tube having a photocathode having a transmission line configuration, the pulse of light travelling along the first beam path striking the photocathode,

d. a voltage pulse generator for receiving the light from the second beam path and outputting a voltage pulse in response thereto, said test device being coupled to said output, and

e. means connecting the output of the test device to the photocathode of the photomultiplier tube so as to apply a bias voltage to said photocathode.

12. The system of either claim 10 or claim 11 and further including recording means.

11. A system for time resolving luminescence from a sample comprising:

a. means for generating a pulse of light,

b. means for splitting the pulse of light into first and second beam paths, said sample being disposed along said second beam path,

c. a photomultiplier tube for receiving the light emitted by the sample on illumination by the portion of the light pulse travelling along the second beam path, said photomultiplier tube having a photocathode having a transmission line configuration,

d. a voltage pulse generator for receiving the light pulse traveling along the first beam path and outputting a voltage pulse in response thereto, and

e. means connecting the output of the voltage pulse generator to the photocathode of the photomultiplier tube so as to apply a bias voltage pulse to said photocathode.