OptoTest OP815 User manual

(Also supports the OP850)
www.optotest.com 1.805.987.1700
Insertion Loss Test Set
Instruction Manual
OP815

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Contacting OptoTest Corporation
1.805.987.1700 (7:30 a.m. to 5 p.m. PST)
www.optotest.com
[email protected]
OptoTest Corp.
4750 Calle Quetzal
Camarillo, CA 93012 USA
Notice of Proprietary Rights
The design concepts and engineering details embodied in this manual, which are the
property of OptoTest Corporation, are to be maintained in strict condence. No element
or detail of this manual is to be spuriously used or disclosed without the express written
permission of OptoTest Corporation. All rights are reserved. No part of this publication
may be reproduced, stored in a retrieval system, or transmitted in any form or by any
means, electronic, mechanical, photocopying, recording, or otherwise, without prior
written permission from OptoTest Corporation.
COPYRIGHT © 2017 by OptoTest Corp
ALL RIGHTS RESERVED
PRINTED IN THE UNITED STATES OF AMERICA
MnOP815-RevE

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Table of Contents
Overview 3
Initial Preparation 4
Denition of Specications 5
Front Panel Operation OP815 9
Front Panel Operation OP850 11
Display Operation OP815/OP850 13
Smart Remote Head Option 14
USB Control of the OP815/OP850 15
Warranty Information 16

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Overview
The OP815 oers an economical approach for insertion loss measurements for either
singlemode cables or multimode cables. For the multimode testing the OP815 is
equipped with an 850nm LED, a 1300nm LED or a switched 850nm/1300nm dual
LED source. The sources for the single mode conguration consists of Fabry-Perot
LASERs with 1310nm and 1550nm wavelengths. For all those models, the power
meter is equipped with a ber terminated InGaAs detector.
For specic applications, such as plastic optical ber (POF), the OP815 can be equipped
with various LED sources (480/630/650/850nm) with internal launch bers of various
sizes (50μm to 900μm). For lower wavelength sources the power meter is equipped with
a 3mm Si (silicon) detector.
Dual wavelength instruments: With dual wavelength instruments, that have a single
combined optical port, the sources are either internally switched (multimode) or optically
combined (single mode). With those instruments only one optical source is active at a
time.
OP850 (Multichannel IL Test Set)
The OP850 is similar to the OP815 in that it is primarily an insertion loss test set with a
source and a power meter. The OP850 is a multichannel version of the OP815. Both the
OP815 and OP850 have similar modes (OPM, IL, and SRC). These modes function the
same, but the only dierence is the front panel button behave a little dierent for the two
units.

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Initial Preparation
Unpacking and Inspection
The unit was carefully inspected, mechanically, electrically and optically before shipment.
When received, the shipping carton should contain the items listed in Standard Contents.
Account for and inspect each item. In the event of a damaged instrument, write or call
OptoTest Corp, California.
Note: Be aware that accessories such as detector adapters, remote head detectors, and
high performance reference cables will be located inside a small box labeled “Accessories
Inside”. If this box is not included with the original shipment, contact OptoTest of their
nearest distributor.
Please retain the shipping container in case re-shipment is required for any reason.
Damaged In Shipment
All instruments are shipped F.O.B. Camarillo when ordered from OptoTest.
If you receive a damaged instrument you should:
1. Report the damage to your shipper immediately.
2. Inform OptoTest Corporation.
3. Save all shipping cartons.
Failure to follow this procedure may aect your claim for compensation.
Standard Contents
1. Model OP815/OP850 Insertion Loss Meter
2. Power Cord (U.S. Shipments only)
3. USB A-B cable
4. Certicate of Calibration and if requested the Metrology Report
5. Instruction Manual(s)
6. CD/USB drive with applicable software and documentation (if ordered)
7. Rack mount kit (optional)

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Denition of Specications
Dynamic Range
The dynamic range, or measurement range, of the optical power meter spans from the
maximal power level the instrument can measure, without major saturation to the detector,
to the minimal power level where the thermal noise of the detector becomes greater
than the current produced by the incident light. For accurate power measurements, it is
NOT recommended to measure power levels at either end of the dynamic range. (see
Linearity). The dynamic range is measured by comparing the absolute measured power
against a reference power. When the difference between the two exceeds 1dB either
end of the dynamic range has been reached.
Linearity
Photodetectors are, by nature, very linear over a wide range of optical input powers,
but the power meter electronics can affect the overall system linearity. The power meter
linearity is characterized and specified to know the measurement accuracy and linearity
over the full dynamic range. For accurate insertion loss measurements only power levels
that fall within the range with the best linearity (+/-0.05dB or better) should be measured.
Calibration Wavelength
The calibration wavelengths are the nominal wavelengths of the instruments calibration
points. The exact wavelength of each particular calibration is stated in the certificate of
calibration.
Calibration Traceability
The detector’s absolute calibration data is directly traceable to N.I.S.T. at the specified
calibration wavelength and the specified power level, typically -10dBm.

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Denition of Specications
Spectral Responsivity
Depending on the detector type, InGaAs (Indium Gallium Arsenide) or Silicon the spectral
responsivity, the eciency of the detector to convert optical power into electrical current
changes with wavelength.
Responsivity of InGaAs Detectors Responsivity of Silicon Detectors
Note that other detector types are available such as IN5 (5mm InGaAs) IN10 (10mm InGaAs)
as well as WSR (wide spectral range) and might exhibit a different spectral responsivity.
Absolute Accuracy
The absolute accuracy specification includes the total measurement uncertainties
involved in the calibration process including the transfer of the absolute power standard
from N.I.S.T. Contact OptoTest for the detailed chain of uncertainties.
Optical Power Meter, Channel Performance
For multichannel instruments, the power meter circuit converts and digitizes the optical
power level with the given sampling interval. Changes in light levels such as modulation
will be averaged within that sampling interval.
Instrument, Warm up Time
Optical power meters, in general, do not need any warm-up time unless the instrument
has to acclimate to a changing environment. In order to calibrate the instrument or to
perform stable measurements, the instrument should be acclimated for 15 minutes for
each 5ºC of temperature differential. For example if the instrument was stored at 18ºC
and brought into an environment of 28ºC the instrument should be allowed to warm up
for 30 minutes.

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Denition of Specications
Recommended Recalibration Period
This is the recommended time period for re-calibration in order to maintain accuracy
specifications. The recommendation is made based upon statistics on detector aging;
however it is up to the metrology policies and procedures within each company to
define the calibration cycles on optical power meters.
Optical Power Meter, Fiber Compatibility
The amount of aerial coverage of the detector, or the portion of the light emitted from
the fiber being measured, depends on the mechanical features of the optical interface,
the active area of the detector and the numerical aperture (NA) of the fiber. A fiber with a
large NA, for example 100/140 multimode fiber, might not under fill a small area detector
hence the absolute power reading will be less than actual.
Return Loss Range
The lower end of the return loss (low return loss = high reflection) defines the level where
the instrument is saturated by large reflections. The higher end of the return loss (high
return loss = very weak reflections) is given by capability of the instrument to amplify and
resolve reflection out of the noise floor.
Return Loss Accuracy
The Return Loss Accuracy is measured using an optical variable attenuator
connected to a >98% reflector. The insertion loss of the attenuator is initially
quantified against a reference optical power meter. The actual attenuation is
then used to calculate the generated reflection, where the resulting reflection
= 2x (variable attenuation + insertion loss of attenuator) + reflector coefficient.
Accuracy of return loss measurements can also be affected by the reference cable and
any excessive losses at the front panel interface.

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Definition of Specifications
Reference Cable
The reference cable is the cable with which the DUTs will be measured against. Typically
reference cables are required to be of a defined quality with a specified connector/
endface polish.
Instrument, Environmental
Operating Temperature: This is the temperature range in which the instrument will
conform to the specifications after the specified warm up time.
Storage Temperature: This is the temperature range at which the instrument can
be stored with the power off without any damage or any loss of specification to the
instrument. It is required that the instrument be brought back to within the operating
temperature range before it is turned on.
Humidity: The relative non-condensing humidity levels allowed in the operating
temperature range.

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Wavelength
The wavelength button 1 toggles through the available calibration wavelengths and
source selection depending on the mode of the instrument.
OPM Mode: The measurement wavelengths for the OP815 are 850nm, 1300nm,
1310nm, 1480nm, and 1550nm for InGaAs detectors and 650nm, 850nm, and 980nm
for silicon detectors, unless otherwise noted.
IL Mode: The wavelength button toggles the source wavelength concurrently with the
power meter calibration wavelength. For OP815 with a single wavelength source there
is no wavelength to be selected, for dual wavelength implementations the wavelength
selection switches between the two sources.
Source Mode: The wavelength button toggles the source wavelength.
Reference
For OPM Mode: The Ref button 2 switches the power meter into relative measurement
mode. At the same time it stores the current absolute power reading at the current
wavelength as the reference. The reference power is displayed above the relative power
reading (see illustration of Display). If the instrument is already in relative measurement
mode pressing the Ref button stores the current power level as the new reference. For
each wavelength a reference reading can be stored.
Front Panel Operation – OP815
Mode
Indicator
Power Reading
Wavelength
Reference
Absolute Measurement
Mode Selection
(OPM, IL, Source)
Internal (ambient)
Temperature
Wavelength
Indicator

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Front Panel Operation – OP815
IL Mode: Pressing the Ref button in IL mode executes a reference cycle. For single
wavelength devices, or dual wavelength instruments with individual ports this involves
taking the reference at the selected wavelength. For dual wavelength instruments this
involves taking the reference for the first wavelength, then repeats the same for the
second wavelength. The referencing cycle can take up to 5 seconds.
Absolute Measurement [dBm]
The dBm button switches the power meter into absolute measurement mode.
The OP850 has a mode button [mode] in place of this button. When pressed this button
operates the same as the buttons described below.
Mode Selection
For the OP815 the mode selection buttons switch between modes.

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Wavelength
The wavelength button 1 toggles through the available calibration wavelengths and
source selection depending on the mode of the instrument.
OPM Mode: The measurement wavelengths for the OP850 are 850nm, 1300nm,
1310nm, 1480nm, and 1550nm for InGaAs detectors and 489nm, 650nm, 850nm,
980nm, and 1080nm for silicon detectors, unless otherwise noted.
IL Mode: The wavelength button toggles the source wavelength concurrently with the
power meter calibration wavelength. For OP850 with a single wavelength source there
is no wavelength to be selected, for dual wavelength implementations the wavelength
selection switches between the two sources.
Source Mode: The wavelength button toggles the source wavelength.
dB/dBm
For OPM Mode: The dB/dBm button 2 switches the power meter into relative
measurement mode. At the same time it stores the current absolute power reading at
the current wavelength as the reference. The reference power is displayed above the
relative power reading (see illustration of Display). If the instrument is already in relative
measurement mode pressing the dB/dBm button stores the current power level as the
new reference. For each wavelength a reference reading can be stored.
Front Panel Operation – OP850
Mode
Indicator
Power Reading
Wavelength
dB/dBm
Mode Selection
(OPM, IL, Source)
Channel Selection
Internal (ambient)
Temperature
Wavelength
Indicator

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Front Panel Operation – OP850
IL Mode: Pressing the dB/dBm button in IL mode executes a reference sequence.
For single wavelength devices, or dual wavelength instruments with individual ports
this involves taking the reference at the selected wavelength. For dual wavelength
instruments this involves taking the reference for the first wavelength, then repeats the
same for the second wavelength. The referencing cycle can take up to 5 seconds.
Mode Selection
For the OP850, the mode selection buttons switch between modes.
Channel Selection
For the OP850, the channel selection buttons change the active channel.

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Mode
Indicator
Power Reading Insertion Loss
Reading
Wavelength
Indicator
Absolute Reference
Power
Internal (ambient)
Temperature
Display Operation – OP815/OP850
Depending on the selected mode the display shows different measurement parameters
and results.
Wavelength
This label displays the currently selected calibration wavelength of the source wavelength
used to measure optical power. Typically the wavelengths are as follows:
OPM Mode: 850nm, 980nm, 1300nm, 1310nm, 1480nm, 1550nm
IL Mode: Multimode 850nm, 1300nm; Single Mode 1310nm, 1550nm
Absolute Power
The absolute power is displayed in dBm.
Relative Power
The relative power is displayed in dB. It is the difference between the reference power
at the corresponding wavelength and the measured absolute power.
Internal Temperature
The internal ambient temperature is displayed in either ºF (Fahrenheit) or ºC (Celsius).
The user can alternate between Fahrenheit or Celsius temperature scales by the
implementation of a USB command.

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Smart Remote Head Option
Certain OP815s and OP850s have the option to include a “Smart Remote Head.” The
smart remote head (SRH) has the ability to hold its calibration and be used with multiple
OptoTest mainframes.
The OP815 and OP850, at power on, will detect the SRH and load it as another OPM
in addition to any other OPMs that are also installed on the unit.
Selecting the Integrating Sphere for IL Measurements
If the OP815 or OP850 has a separate power meter, other than the SRH, then, to
correctly use the integrating sphere for insertion loss measurements the unit needs to
“know” to use the sphere.
For it to load the SRH capability, the SRH must be connected prior to turning on the
system. When the system boots up, it will start in OPM2 mode, which displays the
power measured by the SRH. To set the unit to use the SRH for the IL measurements
IL, IL2 modes one needs to press and hold the Ref button until the OPM label in the top
left corner displays Ref. At that point the unit will use the corresponding power meter
for all IL measurements.
To re-select the default power meter, if the SRH is not the default, one needs to navigate
to the OPM screen and press and hold the Ref button until the top left corner of the
screen displays Ref. The default power will now be used for all IL measurements.

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USB Control of the OP815/OP850
The OP815 and OP850 can be controlled via the USB bus. Upon request, OptoTest
can supply the appropriate DLLs along with sample programs to facilitate the software
creation process. For these DLLs please contact [email protected].

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Warranty Information
OptoTest Corp. warrants this product to be free from defects in material and workmanship
for a period of two years from date of shipment. During the warranty period we will,
at our option, either repair or replace any product that proves to be defective. To
exercise this warranty contact OptoTest Corp. headquarters. You will be given prompt
assistance and return instructions. Repairs will be made and the instrument returned,
transportation prepaid. Repaired products are warranted for the balance of the original
warranty period, or at least 90 days.
NOTE: Do not send instruments for any reason without contacting OptoTest
headquarters first.

For Application Notes, more detailed Testing
Instructions, and the most up-to-date OptoTest
News go to www.optobuzz.com

www.optotest.com
1.805.987.1700