Apparatus, method and system for the calibration of a streak camera

Patent metadata

Field	Value
Publication number	US-10483076-B2
Application number	US-201414913146-A
Country	US
Kind code	B2
Filing date	Aug 7, 2014
Priority date	Aug 21, 2013
Publication date	Nov 19, 2019
Grant date	Nov 19, 2019

Abstract

The present disclosure claims an apparatus, a method and a system for the calibration of a streak camera. A plurality of fiber optic cables is bundled together such that the input ends and the output ends of the fibers are grouped together. Each fiber in the bundle has a distinct and characteristic time taken for light to traverse from the input end to the output end known by the observer. This characteristic time depends on the physical and optical properties of the fibers selected. Calibration light is collected by the fiber input face and travels through the individual fibers in a characteristic time. Individual light pulses will subsequently be detected by the streak camera which converts the time profile of the incoming light pulses into a spatial profile. An observer can compare the observed spatial separation profile to an expected spatial separation profile for calibration.

First claim

Therefore what is claimed is:

1. An apparatus integrated into a streak camera for real-time calibration of a streak camera during acquisition of each streak camera observation, comprising:
a fiber bundle, comprising
a plurality of fibers having an input face and an output face,
the plurality of fibers being made of a material selected on a basis of supporting fiber-optic transmission,

wherein the plurality of fibers comprises at least a first fiber and a second fiber,
wherein a light travel time is defined as the time taken for light to travel from the input face to the output face of the fiber,
wherein at least one time difference between light travel times is known; and

wherein after acquisition of each streak camera observation, processing light signals emitted from said output face of said fibers through the streak camera's varying electric field to convert the light signals' temporal profile to a spatial profile, comparing the spatial profile, acquired at the same time as the streak camera observation, to a known calibration profile in order to correct for unwanted drift, amplitude variation and phase variation for each streak camera observation.

2. The apparatus as claimed in claim 1 , wherein the first fiber has a different length than the other fibers and the time difference is related to a difference of lengths between the first fiber and the other fibers.

3. The apparatus as claimed in claim 1 , wherein the first fiber has at least one of a difference of index of refraction and a difference in optical properties than the other fibers; and
wherein the time difference is related to a difference between velocities of light through the first fiber and the second fiber.

4. The apparatus as claimed in claim 1 wherein the fibers at the output face are evenly positioned about a circle with a chosen radial distance from a center of the output face.

5. A method for real-time calibration of a streak camera during acquisition of each streak camera observation, comprising:
assembling a fiber bundle comprising a plurality of fibers wherein one end is designated as an input face and one end is designated as an output face;
forming the plurality of fibers from a material selected on a basis of supporting fiber-optic transmission; and
during acquisition of each streak camera observation, receiving light signals into the input face of at least two of the plurality of fibers, wherein the light signals traveling through a first fiber exits the output face at a first time and the signals traveling through a second fiber exits the output at a second time, and wherein a time difference between said first time and said second time is known; and
after acquisition of each streak camera observation, processing light signals emitted from said output face of said fibers through the streak camera's varying electric field to convert the light signals' temporal profile to a spatial profile, comparing the spatial profile, acquired at the same time as the streak camera observation, to a known calibration profile in order to correct for unwanted drift, amplitude variation and phase variation for each streak camera observation.

6. The method as claimed in claim 5 , wherein the first fiber has a different length than the second fiber.

7. The method as claimed in claim 6 , wherein the time difference is related to a difference of lengths between the first fiber and the second fiber.

8. The method as claimed in claim 5 , wherein the first fiber has at least one of a difference of index of refraction and a difference in optical properties than the second fiber.

9. The method as claimed in claim 8 , wherein the time difference is related to a velocity difference between velocities of light through the first fiber and the second fiber.

10. The method as claimed in claim 5 , wherein the input face is positioned to receive back reflected excitation light.

11. The method as claimed in claim 5 , wherein the output face is positioned to output light into the streak camera for calibration.

12. The method as claimed in claim 11 , wherein a plurality of output signals exiting the output face at known times are converted by the streak camera from a time separation profile to a space separation profile characterized by the changing electric field produced by the streak camera.

13. The method as claimed in claim 12 , wherein the space separation profile can be compared to an expected space separation profile based on characteristics of the fiber bundle in order to correct for one or more of phase variation error, amplitude variation error and potential drift.

14. The method as claimed in claim 13 , wherein the fiber bundle comprises seven fibers and wherein a comparison between the space separation profile produced by the streak camera and the expected space separation profile can be used to calibrate for phase variation error and amplitude variation error in a single observation.

15. The method as claimed in claim 5 wherein the fibers at the output are evenly positioned about a circle with a chosen radial distance from the center of the output face.

Assignees

• Univ Mcmaster

Inventors

• Tsikouras Anthony
• Fang Qiyin

Classifications

• H01J31/501 Primary

  with an electrostatic electron optic system (H01J31/52 - H01J31/56 take precedence) · CPC title

• H01J31/502

  with means to interrupt the beam, e.g. shutter for high speed photography (circuits using electron-beam shutters G03B27/725) · CPC title

• G03B39/005

  using image converters or amplifiers · CPC title

• G02B6/04

  formed by bundles of fibres (G02B6/24 takes precedence) · CPC title