Hamamatsu Photonics C10910, Инструкция по эксплуатации, Страница: 18 / 105

C10910 INSTRUCTION MANUAL Ver.1.19E
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multiplied into as many as 1000 using this process.
O
Output Optics:
This is an optics which is positioned between the phosphor screen and the readout camera. It
is used to form an image on the readout camera which reads the streak image formed on the
phosphor screen.
P
Phosphor Screen:
This is a screen which produces light when electrons bump against it. This is where the
electron image is optically converted into a streak image. The phosphor screen consists of a
glass plate and layers of fluorescent material on the surface of the plate. The amount of light
generated by the fluorescent material is proportional to the kinetic energy of the electrons.
Photocathode:
This is configured of numerous layers of various types of metallic film, so that when light
strikes this surface, the light energy is absorbed and electrons called photoelectrons are
discharged. The detectable wavelength range of the incident light and the conversion ratio,
differ depending on the material making up the photocathode.
Q
Quantum Efficiency:
This is the ratio between the number of incident photons on the photocathode and the
number of photoelectrons generated. It is calculated using the following equation:
No. of photoelectrons / No. of incident photons x 100 (%)
R
Radiant Sensitivity:
This expresses how many amperes (A) of photoelectric current are produced from one watt
(W) of incident light on the photocathode. It can be expressed as the (A/W) of the incident
light and the photoelectric current.
S
Space- temporal Resolution Measurement:
This is a process which measures temporal changes in the light intensity by identifying the
position of the light being measured. This is done by collecting the optical images to the input
slit of the streak camera using input optics.
Shift blanking
This function is used for systems that combine a synchroscan unit with a low-repetition laser
based on a high-repetition laser, such as a system combining a titanium-sapphire laser and a
pulse picker. Though dependent on the frequency setting, synchroscan units measure light
emission phenomena with a maximum time length of approximately 2 ns. In this case, if a
light emission phenomenon longer than the measurement range, s
uch as about 1 μs, occurs
at the same time, then the back sweep will overlap the short light emission to be measured.
The shift blanking function prevents this problem by eliminating the return sweep on the long
light emission phenomenon from the CCD field of view. So using shift blanking in low jitter
synchroscan measurement allows finding just the short light emission in the range of interest.