Chapter 3 Setup - THORLABS DET10A User Manual

Si Biased Detector

Chapter 3 Setup

The detector can be set up in many different ways using our extensive line of
adapters. However, the detector should always be mounted and secured for best
operation. Step 1 in the setup instructions below outline how to mount the detector
onto a post.
1. Unpack the optical head, install a Thorlabs TR-series ½" diameter post into
one of the #8-32 (M4 on /M version) tapped holes, located on the bottom and
side of the sensor, and mount into a PH-series post holder.
2. Attach a 50 Ω coax cable (i.e. RG-58U) to the output of the DET. Select and
install a terminating resistor to the remaining end of the cable and connect to
a voltage measurement device. See Chapter 4, page 4 to determine resistor
values. Thorlabs sells a 50 Ω terminator (T4119) for best frequency
performance and a variable terminator (VT2) for output voltage flexibility. Note
the input impedance of your measurement device since this will act as a
terminating resistor. A load resistor is not necessary when using current
measurement devices.
3. Power the DET on using the power switch. To check battery voltage, see the
Battery Check section on page 7.
4. Install any desired filters, optics, adapters, or fiber adapters to the input
aperture.
!
The DET10A(/M) was designed to allow maximum accessibility to the
photodetector by having the front surface of the diode flush with the
outside of the DET housing. When using fiber adapters, make sure that the
fiber ferrule does not crash into the detector. Failure to do so may cause
damage to the diode and or the fiber. An easy way to accomplish this is to
install a SM1RR retaining ring [included with the DET10A(/M)] inside the 1"
5. During alignment, take appropriate precautions, such as using reduced
radiation power, or other precautions, and use proper eye and/or skin
protection as recommended by the radiation source manufacturer.
6. Apply a light source to the detector.
Rev I, September 28, 2017
threaded coupler before installing the fiber adapter.
Caution!
Chapter 3: Setup
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