Optical Chopper ? 200mm disc Model 340CD0 pages

Optical Chopper – 200mm disc
Model 340CD
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Scitec Instruments Model 340CD is a high
stability variable frequency optical chopper. The
basic system consists of control unit, chopping
head and a choice of one of two chemically
blacked photo etched discs. This system
provides operation over the frequency range 5
Hz to 220 Hz, depending on the choice of disc.
A selection of additional discs and accessories
is available to satisfy individual requirements.

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Chopping frequency can be controlled externally by
applying an analogue voltage to a ‘Control’ BNC. A
‘Reference’ BNC provides a TTL level output,
generated directly from the opto-switch on the
chopping head. This signal has constant phase
relative to the chopping action and can be used as
the reference for other instruments such as lock-in
amplifiers.

↑ 340CD chopper system

Features
→ The Model 340CD is an optical chopper based on
200 mm diameter discs.
→ The larger disc size allows larger diameter beams
to be chopped. Unfortunately, it does not allow
smaller diameter beams to be chopped at a faster
rate.
→ 5 Hz – 220 Hz standard frequency range,
depending on disc choice.
→ The chopper system comes with a choice of two
200mm discs.

↑ 340P Blade Protector

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The 340H chopping head supplied with the
standard system may be bench bolted or optical
stalk (bench rod) mounted. Mountings are provided
to enable parts, such as a blade protector, to be
attached.

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Standard discs are chemically blacked. Other
finishes, such as gold plating, are available. See
our website, www.scitec.uk.com for more details.

↑ 340H chopper head

Model_340CD_issue1.0

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