Electro-Optics Technology, Inc.
Electro-Optics Technology, Inc. | 3340 Parkland Ct. Traverse City, MI 49686 USA
customer to modify the device. All returns should reference the RMA number on the
outside of the shipping container and should be sent to:
Electro-Optics Technology, Inc.
Attn: Sales/Customer Service
3340 Parkland Ct.
Traverse City, MI 46986 USA
EOT reserves the right to inspect photodetectors returned under warranty to assess if the
problem was caused by a manufacturer defect. If EOT determines the problem is not due
to a manufacturer defect, repairs will be done at the customer’s expense. EOT will
always provide a written quote for repair prior to performing repairs at the customer’s
expense.
VI. Glossary of Terms
Amplifier: Provides a transimpedance gain throughout the photodiode’s bandwidth. The
photodiode current is converted to an output voltage.
Bandwidth: Unlike non-amplified photodetector bandwidth, which is defined as the
range of frequencies from 0 Hz (DC) to the frequency at which the amplitude decreases
by 3 dB, the amplified photodetectors have a low frequency cutoff of -3 dB, which is
greater than 0 Hz due to the DC Block Capacitor. Bandwidth and rise time can be
approximately related by the equation:
Bandwidth ≈ 0.35/rise time for a Gaussian pulse input.
Bias Voltage: The photodiode’s junction capacitance can be modified by applying a
reverse voltage. The bias voltage reduces the junction capacitance, which causes the
photodiode to have a faster response.
BNC Connector: Used to connect the customer’s coaxial cable.
Conversion Gain: The relative level of the optical input power that is amplified and
converted into a voltage output.
DC Block Capacitor: Prevents the DC voltage that is supplied through the amplifier
output from exiting the detector which would cause a large DC offset voltage. Therefore,
the amplified detector is an AC coupled device and will have a low cut-off frequency as
well as a high cut-off frequency.
Decoupling Capacitor: Maintains bias voltage when fast pulses cause the battery
voltage to reduce (this would slow the response time of the photodiode); the capacitor
allows the battery to recover to its initial voltage. It also acts as a low-pass filter for
external power supplies.
