Electro-Optics Technology ET-2060, ET-2030, ET-2040, ET-2070, ET-3000 User Manual

Electro-Optics Technology, Inc.

3340 Parkland Ct. Traverse City, MI 49686 USA

[phone] ׀ [phone] ׀ [e-mail] ׀ www.eotech.com

Page 1 of 9

Non-amplified

Photodetectors

User Guide

Electro-Optics Technology, Inc.

3340 Parkland Ct. Traverse City, MI 49686 USA

[phone] ׀ [phone] ׀ [e-mail] ׀ www.eotech.com

Page 2 of 9

EOT NON-AMPLIFIED PHOTODETECTOR USER’S GUIDE

Thank you for purchasing your Non-amplified Photodetector from EOT. This user’s guide will help answer any
questions you may have regarding the safe use and optimal operation of your Non-amplified Photodetector.

TABLE OF CONTENTS

I. Non-amplified Photodetector Overview .......................................................................................................... 2

II. Operation of your EOT Non-amplified Photodetector .................................................................................... 2

III. Troubleshooting ............................................................................................................................................... 3

IV. Drawings: Non-amplified Photodetectors ....................................................................................................... 4

V. Specifications: Non-amplified Photodetectors ................................................................................................ 6

VI. Schematics: Non-amplified Photodetectors ..................................................................................................... 7

VII. Warranty Statement and Repair ..................................................................................................................... 7

VIII. Glossary of Terms ......................................................................................................................................... 8

I. Non-amplified Photodetector Overview

EOT’s Non-amplified Photodetectors contain PIN photodiodes that utilize the photovoltaic effect to
convert optical power into an electrical current. Figure 1 below identifies the main elements of your
Non-amplified Photodetector.

Figure 1: EOT Non-amplified Photodetector

When terminated into 50Ω into an oscilloscope, the pulsewidth of a laser can be measured. When
terminated into a spectrum analyzer, the frequency response of a laser can be measured.

II. Operation of your EOT Non-amplified Photodetector

A. Caution: Eye safety precautions must be followed when utilizing any equipment used in the vicinity

of laser beams. Laser beams may reflect from the surface of the detector or the optical mount and
caution must be exercised.

Sensor

Aperture

BNC

Connector

Electro-Optics Technology, Inc.

3340 Parkland Ct. Traverse City, MI 49686 USA

[phone] ׀ [phone] ׀ [e-mail] ׀ www.eotech.com

Page 3 of 9

B. Mount the detector to an optical stand by the mounting holes on the bottom of the detector housing.
C. Adjust the voltage of the oscilloscope to 100mV/division before connecting the detector. On models

with >3V bias supply, the signal may be large enough to damage the oscilloscope if this is not done.

D. Connect the detector to the oscilloscope using a 50Ω coaxial cable that one meter or less.
E. Use the 50Ω termination input of the oscilloscope. If the oscilloscope does not have a 50Ω input,

connect the coaxial cable to a 50Ω terminator and connect this to the oscilloscope’s 1MΩ input.

F. After being certain that the damage threshold of the detector is not exceeded, place the detector in

the center of the laser beam.

III. Troubleshooting

A. No signal is seen the first time the detector is used.

1. Be certain that the signal is not high off scale on the oscilloscope.

2. Is the wavelength of the laser within the spectral range of the detector?

3. Has a 50Ω termination input been used?

4. Try moving the detector within the laser beam.

5. Is there enough light (see sensitivity spec on the data sheet) incident on the detector to generate a

signal?

B. A signal has been previously obtained, but not currently.

1. Try steps listed under A.

2. Inspect the active area of the photodiode for any signs of damage.

3. Try a higher input termination on the oscilloscope, but remember to return to 50Ω if this does not

work.

4. Test the power supply:
a. Units with internal batteries will typically operate for several years, but operation with CW

or high rep rate lasers can drain the batteries much faster. If a load is present at the output,

current will be drawn from the batteries, so disconnect the BNC when not in use.

Remove top cover to replace the 3V lithium cells with Duracell Model DL2430, positive side
down.

b. Units with an external power supply should at least receive the voltage that is printed on the

plug.