© 2018 Thorlabs6
PDF10x
3 Operating Instruction
·
Turn the power switch to on ("I") while the optical input is protected by the metal cover cap.
·
Please check, that OUTPUT offset voltage is within the range listed in Technical Data. A
small drift during warm up period (~5min) is typical.
·
Please also check, that noise level is not higher than 5mVRMS. If noise level is significantly
higher, please refer to recommendations and optimize your setup.
·
Remove the metal cover cap to detect your optical signal.
·
If necessary, mount external optics, filters, apertures or fiber adapters.
·
The maximum OUTPUT voltage swing is +10V for high impedance loads (>10kOhm). The
OUTPUT signal should be below this maximum output voltage to avoid amplifier saturation.
·
Turn the power switch to O when you are finished the measurements.
Note
To prevent saturation of the amplifier keep the optical input powers less than the saturation
power listed in Technical Data.
Attention
Refer to the Technical Data and pay attention to the optical damage threshold! Exceeding
these values will permanently destroy the detectors!
3.1 General Principle of Operation
The Thorlabs PDF10x series Femtowatt Photoreceivers combines a very low noise Silicon or
InGaAs photodiode with a specially designed ultra low noise transimpedance amplifier with ex-
tremely high gain of up to 1012V/A. This unique combination results in a photoreceiver with
femtowatt sensitivity due to its exceptional low NEP, making them ideal for low-light level detec-
tion applications, such as spectroscopy and fluorescence measurements. Direct detection of
optical power down to ~10 fW is possible; in combination with an optional Lock-In Amplifier
even sub-femtowatt sensitivity can be achieved.
An integrated ultra low noise high gain amplifier provides output signals in the range up to 10V,
the output is short circuit proof.
The new slim line housing includes a removable threaded coupler that is compatible with a
number of Thorlabs 1” and ½” threaded accessories. This allows to conveniently mount ex-
ternal optics, filters, apertures or fiber adapters, as well as providing an easy mounting mechan-
ism using the Thorlabs cage assembly accessories. The PDF10x has three tapped mounting
holes.
The PDF10x is powered by an LDS12B external linear power supply (±12V, 250mA) via a
PICO M8 power connector.
In case of open beam, make sure that the beam is aligned properly to the detector input. If ne-
cessary, use a focusing lens in front of the detector.
If the PDF10x is used in fiber based applications we recommend a Thorlabs fiber connector ad-
apter for coupling between fiber and PDF10x. Please see Ordering Codes and Accessories
for details.
Please note, that coupling losses may occur due to small detector size, which will result in a re-
duced output signal. If angled connectors are used, the FC adapter can be rotated from its ori-
ginal position to check for an improved alignment. For this process apply an input signal with
power below the saturation level while observing the output voltage using a digital voltmeter or
other low-frequency measurement device.
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