Photosensors or photodetectors are sensors of light or other electromagnetic energy. There are several varieties:[1|http://en.wikipedia.org/wiki/Photodetector#cite_note-0]
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Please Note: Due to limitations in the IC, the high speed amplifier used in these devices may become unstable, exhibiting oscillations or negative output, if the power supply voltage is applied when the module is on. The unit should always be powered up using the power switch on the power supply or the unit itself. Hot plugging the unit is not recommended. http://www.thorlabs.com/NewGroupPage9.cfm?ObjectGroup_ID=4&pn=PDA10CS
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This model is: PDA100A2, Silicon Amplified PD (320-1100nm) 
Location: 26-352
Bandwidth: 11 MHz
Active Area: 75.4 mm2
Vendor: Thorlabs
Manual: User Guide
Specifications: Datasheet
Price: $381.99
Purchase Date: 11/13/2020 (by Yannick)
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This model is: APD430C, InGaAs Variable-Gain Avalanche Photodetector (900-1700nm)
Location: 26-352
Bandwidth: DC - 400 MHz
Active Area: 0.2 mm Ø
Vendor: Thorlabs
Manual: User Guide
Specifications: Datasheet
Price: $2,489.95
Purchase Date: June 2020 (by Yannick)
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This model is: PDA10CS, InGaAs PIN (700-1800nm) 
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