Plug-in Sweep Units Available: Fast Sweep Unit

Slow Sweep Unit

Video output (Video CCD Camera)*

Output

format

Cooled Digital Camera C4742-95

Camera head

Control unit

Frame Grabber

Streak Image

Analysis

Software

Streak Image

Analysis Systems

for IBM

Lens output

Personal computer

(IBM PC/AT Compatible)

C2830 Main body

Sweep units

Readout system

(HPD-TA)

SYSTEM CONFIGURATION

OPERATING PRINCIPLE

The streak camera converts incident light into electrons and

performs a high-speed sweep (deflecting electrons from top to

bottom), enabling detection of the time variation of the incident

light intensity by converting these into different positions on the

screen. The figure below shows the operating principle of the

streak tube, which forms the heart of the streak camera.

The light pulse to be measured is focused onto the photocath-

ode of the streak tube through the slit, where the photons are

converted into a number of electrons proportional to the inten-

sity of the incident light. These electrons are accelerated and

conducted towards the phosphor screen, and a high-speed

voltage which is synchronized to the incident light is applied.

The electrons are swept at high speed from top to bottom and

are then multipled in the MCP (micro-channel plate), after which

they are bombarded against the phosphor screen of the streak

tube and converted to an optical image.

The optical image which appears on the phosphor screen is

called a streak image, and shows the intensity distribution of the

incident light, by which the positions of the electrons can be

Optical

intensity

Time

Space

Trigger signal

Slit

Lens

Incident light

Photocathode

(photons

→ electrons)

Phosphor screen

(electrons

→ light)

MCP

(which multiplies

electrons)

Streak image

on phosphor screen

Time

Space

Sweep electrode

(where electrons

are swept in the

direction from top

to bottom)

Sweep circuit

Accelerating electrode

(where electrons

are accelerated)

The intensity of the incident light

can be read from the brightness

of the phosphor screen, and the

time and space from the position

of the phosphor screen.

determined in the perpendicular direction over the passage of

time. Using this method, the temporal intensity distribution of

the light being measured can be displayed as the spatial

intensity distribution on the phosphor screen.

APPLICATIONS

q

Research involving free electron lasers and various

other types of pulsed lasers

q

Plasma light emission, radiation, laser ablation, com-

bustion and explosions

q

Fluorescence lifetime measurement, transient absorp-

tion measurement, time-resolved Raman spectroscopy

q

Lidar, Thomson scattering, laser distance measurement

5 Built in main body.

[Operating Principle of the Streak Tube]