Newport 840-C User manual

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i
Model 840-C HandHeld
Optical Power Meter
OPERATOR'S
MANUAL
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ii
Warranty
Newport Corporation warrants this product to be free from
defects in material and workmanship for a period of 1 year
from the date of shipment. If found to be defective during the
warranty period, the product will either be repaired or
replaced at Newport’s option.
To exercise this warranty, write or call your local Newport
representative, or contact Newport headquarters in Irvine,
California. You will be given prompt assistance and return
instructions. Send the instrument, transportation prepaid, to
the indicated service facility. 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.
Limitation of Warranty
This warranty does not apply to defects resulting from
modification or misuse of any product or part. This warranty
also does not apply to fuses, batteries, or damage from
battery leakage.
This warranty is in lieu of all other warranties, expressed or
implied, including any implied warranty of merchantability or
fitness for a particular use. Newport Corporation shall not be
liable for any indirect, special, or consequential damages.
Statement of Calibration
This instrument has been inspected and tested in accordance
with specifications published by Newport Corporation.
The accuracy and calibration of this instrument and the
photodetector are traceable to the National Institute for
Standards and Technology through equipment which is
calibrated at planned intervals by comparison to the certified
standards maintained at Newport Corporation.
Copyright 1990, Newport Corporation
Part No. 17492-02, Rev. J
IN-03901 (08-00)
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iii
VP European Operations General Manager-Precision Systems
Zone Industrielle 1791 Deere Avenue
45340 Beaune-la-Rolande, France Irvine, Ca. USA
We declare that the accompanying product, identified with the
"" mark, meets the intent of the Electromagnetic Compatability
Directive, 89/336/EEC and Low Voltage Directive 73/23/EEC.
Compliance was demonstrated to the following specifications:
EN50081-1 EMISSIONS:
Radiated and conducted emissions per EN55011, Group 1,
Class A
EN50082-1 IMMUNITY:
Electrostatic Discharge per IEC 1000-4-2, severity level 3
Radiated Emission Immunity per IEC 1000-4-3, severity level 2
Fast Burst Transients per IEC 1000-4-4, severity level 3
Surge Immunity per IEC 1000 4-5, severity level 3
IEC SAFETY:
Safety requirements for electrical equipment specified in
IEC 1010-1.
Alain Danielo Jeff Cannon
EC DECLARATION OF CONFORMITY
Active Isolation Module Set Series
Model 840-C
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Table of Contents
i. Warranty ...................................................................... ii
ii. EC Declaration of Conformity ................................... iii
iii. List of Figures ............................................................. vi
iv. List of Tables .............................................................. vi
v. Definitions.................................................................. vii
vi. Specifications ........................................................... viii
Section 1 - General Information
1.1 Introduction ................................................................. 1
1.2 Manual Addenda ......................................................... 1
1.3 Product Description ................................................... 2
1.3.1 General Warnings and Cautions ....................... 3
1.4 Getting Started ............................................................ 4
1.5 Unpacking and Inspection .......................................... 4
1.6 Specifications .............................................................. 4
1.7 Warranty Information ................................................. 4
1.8 Safety Symbols and Terms ......................................... 5
Section 2 - Principles of Operation
2.1 Introduction ................................................................. 6
2.2 Photodetector ............................................................. 6
2.3 Memory Module .......................................................... 6
2.4 Functional Description ............................................... 7
2.4.1 Input Amplifier ................................................... 9
2.4.2 Microprocessor and Detector Cal Module
(E2PROM) ............................................................ 9
2.4.3 AC Wall Mount Adapter ..................................... 9
2.4.4 Ni-Cd Rechargeable Batteries ......................... 10
2.4.5 Reset Switch ..................................................... 10
2.5 Measurement Considerations .................................. 10
2.5.1 Quantum Detector Calibration and Accuracy 10
2.5.2 Quantum Detector Temperature Effects ........ 11
2.5.3 Ambient and Stray Light .................................. 11
2.5.4 Environmental Measurement Conditions ...... 12
2.6 System Accuracy ....................................................... 13
Section 3 - System Operation
3.1 Introduction ............................................................... 14
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3.2 Preparation for Use ................................................... 14
3.2.1 Battery Charging .............................................. 14
3.2.2 Sensor Connection/Removal ........................... 15
3.2.3 Power Up .......................................................... 16
3.3 Model 840-C Controller ............................................. 17
3.3.1 Digital Display .................................................. 17
3.3.2 Front Panel Controls ........................................ 18
3.3.3 Input Connectors ............................................. 18
3.3.4 Analog Output .................................................. 19
3.4 Definition of Key Functions ...................................... 20
3.4.1 Shift ................................................................... 20
3.4.2 Hold ................................................................... 20
3.4.3 Attenautor ........................................................ 20
3.4.4 Background ...................................................... 20
3.4.5 W-dBm ............................................................... 20
3.4.6 Avg/P-P .............................................................. 21
3.4.7 REF-dB ............................................................... 21
3.4.8 Store Reference ................................................ 21
3.4.9 Tone .................................................................. 22
3.4.10 Time Constant .................................................. 22
3.4.11 Auto ................................................................... 22
3.4.12 Range ................................................................ 22
3.4.13 Wavelength ....................................................... 23
3.5 Performing Basic Measurements ............................. 23
3.5.1 Setting the Wavelength .................................... 23
3.5.2 Setting the Attenuator Status .......................... 24
3.5.3 Power Measurements ...................................... 25
3.5.4 Background Correction ................................... 25
3.5.5 Ratio Measurements ........................................ 25
3.5.6 Logarithmic Measurements (dBm and dB) ... 26
3.5.6.1 Log measurements:
1 mW Reference (dBm) ....................... 26
3.5.6.2 Log measurements:
Other Reference Powers (dB) ............ 27
3.5.6.3 Store and Recall of Reference Power. 28
3.6 Error Messages ......................................................... 28
Section 4 - Maintenance and Troubleshooting
4.1 Maintenance Procedures ......................................... 29
4.2 Troubleshooting Guide ............................................ 29
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Section 5 - Factory Service
5.1 Introduction ............................................................... 31
5.2 Obtaining Service ...................................................... 31
5.3 Service Form .............................................................. 33
List of Figures
1 Model 840-C Controller and Compatible
Detectors ..................................................................... 2
2 Simplified Functional Block Diagram ........................ 7
3 Detector Cal Module Installation ............................. 15
4 LCD Display Layout .................................................. 16
List of Tables
1 DC Range Electrical Accuracy and Overload
Conditions ................................................................... 8
2 AC Range Electrical Accuracy and Overload Condi-
tions ............................................................................. 8
3 Total System Accuracy ............................................. 13
4 Symptom/Fault Troubleshooting Guide ................. 29
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vii
Definitions
Aamps
ABS flameproof (when treated), rugged plastic
AC Alternating Current
A/D Analog-to-Digital converter
BAT battery option
BIC biconic fiber connector
BNC standard coaxial connector type
°C degrees Centigrade
dB decibels
dBm decibels, referred to 1 mW power level
DC direct current
DIN German National Standard
EDCU Electronic Display and Control Unit
E2PROM electrically eraseable,
programmable read-only memory
°F degrees Fahrenheit
Hz hertz (cycles per second)
IR infrared
I-V current-to-voltage converter
kHz kilohertz
kOhm kiloOhms
LCD liquid crystal display
mA milliamps
mm millimeters
mV millivolts
nA nanoamps
nF nanofarads
Ni-Cd nickel-cadmium
nm nanometers
NVRAM non-volatile random access memory
P-P peak-to-peak
PROM programmable read-only memory
RH relative humidity
SL silicon visible type detector
S/N serial number
ST connector fiber optic connector type
ST silicon wand visible type detector
µA microamps
µS microsecond
V volts
W watts
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Specifications
Physical Specifications
Electronic Display and Control Unit
Dimensions: 7.2" x 3" x 1.5"
Weight: 500 grams
Enclosure: Flame resistant ABS
Connectors: Input: 8-pin sub-mini DIN
Analog Output: BNC
Charger: DC power Jack, 5.5mm.
Photodetectors See the appropriate
instruction manuals and
data sheets for these
specifications
Electrical Specifications
Electronic Display and Control Unit
Input Current To Power Conversion:
Displayed Power Reading: Input Current (A) ÷
Detector Responsivity
(A/W) P=I/R(l)
Input Voltage Burden:5µV at zero current input.
10µV max. at full range,
except 100µV max on 5mA
range.
Input Noise: The noise performance of
the meter is ±1 A-D count
or better when in either the
linear or peak-to-peak
mode, regardless of the
sensor capacitance,
internal resistance or
feedback ranging resistor
(see limits below).
Input Voltage Drift: ±0.6mV/oC; ±1 mV/Mo.
Source Resistance: >30kΩ
Source Capacitance: <14nF
(includes input cable)
Setting Time: 2 seconds to within 1 digit
of final reading
(fast mode)
Reading Rate: 2.5 readings per second
typical
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Analog Output Voltage:
Current Accuracy*Full Range
Range +(%output + offset) Output
100nA 2.5% + 15mV 1V
1µA 2% + 10mV 1V
*(18oC - 28oC, 1 year. Incl. I-V Converter and Output Amp.)
Analog Output Response: 10µS time
constant (typ.)
A-D Output Accuracy: Absolute power measure-
ment accuracy is typically
limited by the calibration
accuracy of the sensor.
For relative power meas-
urements, the electronic
accuracy is often the
limiting factor.
Current Accuracy, P-P Current Sinewave*
Range 50Hz - 1kHz 1 - 2kHz 2 - 5kHz
10uA 1% + 10nA 2% + 10nA 5% + 10nA
100uA 1% + 100nA 2% + 100nA 5% + 100nA
1mA 1% + 1uA 2% + 1uA 5% + 1uA
5mA 1% + 10uA 2% + 10uA 5% + 10uA
Current Accuracy, P-P Current Squarewave*
Range 50Hz - 1kHz 1 - 2kHz 2 - 5kHz
10uA 5% + 10nA 1% + 10nA 2% + 10nA
100uA 5% + 100nA 1% + 100nA 2% + 100nA
1mA 5% + 1uA 1% + 1uA 2% + 1uA
5mA 5% + 10uA 1% + 10uA 2% + 10uA
*(Incl. I-V converter, P-P to DC converter and A-D converter.)
Current Max A-D Accuracy, DC current*A-D
Range Output ±(%Input + Offset) Resolution
100nA 99.99nA 0.5% + 50pA 10pA
1uA 999.9nA 0.25% + 500pA 100pA
10uA 9.999uA 0.25% + 5nA 1nA
100uA 99.99uA 0.25% + 50nA 10nA
1mA 999.9uA 0.25% + 500nA 100nA
5mA 9.999mA 0.25% + 5uA 1uA
*(Includes I-V converter and A-D converter errors.)
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Temperature Coefficient: 0.1 x Appropriate Accuracy
Specification/oC.
Operating Environment: 0oC to 50oC, <80% Relative
Humidity up to 35 oC.
Reduce RH limit by 3%/oC
above 35 oC.
Storage Environment: -25oC - 60 oC, <90% Relative
Humidity up to 35 oC.
Reduce RH limit by 3%/oC
above 35 oC.
Power: 6V, 600mA NiCd battery
pack.
Battery Life: 18 Hours (backlight on)
Battery Indicator: Display indicates when 10%
battery life is left.
Display: Triplexed, backlighted, LCD
System Accuracy: Refer to Table 2.6.1
Measurement Mode:
Display Display Comment
Calculation* Unit
I/R W Lin
(I-Id)/R W Bkgnd,Lin
I/R/Pref —Lin,Ref-dB
(I-Id)/R/Pref —Bkgnd, Lin, Ref-dB
dBm Log
dBm Bkgnd, Log
dBm Log, Ref-dB
dBm Bkgnd, Log, Ref-dB
Pref Store
*When “–––”is displayed, R=1
10 1 log I/R
mW
10 1 log I - Id /R
mW
( )
10 log I/R
Pref
10 log I - Id /R
Pref
( )
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1
Section 1
General Information
This instruction manual contains the necessary informa-
tion for operation and maintenance of the Newport Model
840-C HandHeld Power Meter as well as information for
troubleshooting and obtaining service if necessary. This
information is divided into the following sections:
• Section 1 provides general information about this
manual and the Model 840-C HandHeld Power Meter.
It contains a product description, discusses safety,
and gives the features and options that are available.
• Section 2 explains the principles of operation of the
Model 840-C Power Meter as well as Newport’s Model
818 Series Detectors.
• Section 3 contains system operation procedures for
the HandHeld Power Meter and accessories.
• Section 4 provides for Maintenance and Adjustment
of the HandHeld Power Meter.
• Section 5 provides instructions for obtaining factory
service.
• Section 6 contains reference drawings.
Information concerning changes or improvements to this
instrument which occur after the printing of this manual
will be found on the addendum sheet(s) included with
this manual.
NOTE
Please review the addendum sheet(s) in this manual
before attempting to operate or service this
instrument.
Manual
Addenda
1.2
Introduction
1.1
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The Model 840-C is a powerful handheld dual-micropro-
cessor based optical power measuring instrument. It
makes sensitive DC or AC Peak-to-Peak optical power
measurements with the convenience of full spectrum
sensor calibration, quick sensor change, and a host of
user-friendly features. The Model 840-C and its accesso-
ries are presented in Figure 1.
Figure 1 Model 840-C Controller and Compatible Detectors
The Model 840-C operates with Newport’s line of optical
detectors through the use of an in-line calibration
module. This Cal Module supplies calibration and detec-
tor information while still allowing the detector to be
detached and used with other equipment in the lab. For
use in fiber optic applications, a combined detector-
calibration module provides connectorized input at the
meter (Model 818-F Series modules).
Product
Description
1.3
W-dbm
REF-dB
AVG/P-P
STORE
REF WAVE
LENGTH
AUTO
RANGE
SHIFT
B
1
0
Optical Power Meter
Model 840
Wand Detector
w/Memory Module*
818-ST/CM
*Memory Modules sold with Detectors as shown in dashed boxes.
818-FA3-SMA
818-FA3-FC
818-FA3-BIC
818-FA3-ST
Available
Fiber Optic Adapters
(SMA Standard)
Fiber Optic
Detector Modules
2 versions available
818-F-SL
818-F-IR
Post Mount Detector
w/Memory Modules*
3 versions available
818-UV/CM
818-SL/CM
818-IR/CM
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The Model 840-C has been designed with the most
frequently used keys placed within natural reach. A
backlit
4-digit liquid crystal display (LCD) permits easy reading in
darkened areas. An audio indicator allows the user to
maximize a signal without having to look at the display.
The analog output allows other instrumentation to
monitor the Model 840-C power readings by providing a
voltage output proportional to detector current. The
Model 840-C’s ultra low noise, thermally stable, trans-
impedance input amplifier optimizes the detector sensi-
tivity and linearity.
1.3.1 General Warnings and Cautions
The following general warnings and cautions are appli-
cable to this instrument:
WARNING
This instrument is intended for use by qualified
personnel who recognize shock hazards or laser
hazards and are familiar with safety precautions
required to avoid possible injury. Read the instruc-
tion manual thoroughly before using, to become
familiar with the instrument’s operations and capa-
bilities.
WARNING
The American National Safety Institute (ANSI) states
that a shock hazard exists when probes or sensors
are exposed to voltage levels greater then 42VDC or
42V peak AC. Do not exceed 42V RMS between any
portion of the Model 840-C (and its detector) and
ground or a shock hazard will result.
WARNING
Use only the AC Adaptor provided with the Power
Meter by Newport.
WARNING
Do not exceed 30V RMS between the detector input
connector and earth ground and do not connect any
conducting detector housing to anything that may
have a voltage higher than 30V.
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CAUTION
Avoid making sharp bends in sensor lead wires.
Bending lead wires at a sharp angle can damage the
wire causing sensor failure.
Please carefully read this instruction manual before using
the Model 840-C HandHeld Power Meter. Alignment of the
detector may require care and patience for optimum
performance in some situations. Be especially careful to
observe the warnings and cautions throughout this
manual (see Section 1.8). If any operating instructions are
not clear, contact Newport Corporation.
All Model 840-C HandHeld Power Meters are carefully
assembled, and then inspected mechanically, electrically,
and optically before shipment. Upon receiving this
instrument, check for any obvious signs of physical
damage that might have occurred during shipment.
Report any such damage to the shipping agent immedi-
ately. Retain the original packing materials in case
reshipment becomes necessary.
Detailed specifications of the Model 840-C HandHeld
Power Meter may be found immediately preceding this
section of the instruction manual or in Tables 1, 2 & 3.
Warranty information may be found on the page preced-
ing the Table of Contents in this manual. Should it be
necessary to exercise the warranty, contact your Newport
representative or the factory to determine the correct
course of action. Newport Corporation maintains offices
worldwide; these offices are listed in the General Catalog
and on the back cover of this manual. Information
concerning the application, operation, or service of this
instrument may be directed to any of these locations.
Unpacking and
Inspection
1.5
Getting Started
1.4
Warranty
Information
1.7
Specifications
1.6
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The following safety terms are used in this manual:
The WARNING heading in this manual explains
dangers that could result in personal injury or death.
The CAUTION heading in this manual explains hazards
that could damage the instrument.
In addition, a NOTES heading gives information to the
user that may be beneficial in the use of this instrument.
Saftey Symbols
and Terms
1.8
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Section 2
Principles of Operation
This section contains a brief overall functional description
of the Model 840-C and its detector measurement consid-
erations. Information pertaining to the Model 840-AC wall
mount Adaptor operation is also included. The Model 840
Hand Held Optical Power Meter System typically includes a
photodetector, a memory module, and an electronic
display. Some systems have the photodetector combined
with the memory module (such as those with the fiber
input module).
The photodetector is a sensor which is connected to its
matched Detector Cal Module through a cable with a
standard BNC connector. The photodetector is a semi-
conductor photodiode which generates current propor-
tional to the total amount of light incident upon the
detector. The photodetector is operated without voltage
bias to reduce dark currents and shot noise. The current
is then measured by the 840-C power meter, and con-
verted into optical power as described in Section 2.4.
The memory module is an in-line device that supplies
calibration information about its matched photodetector
to the 840-C power meter. It is connected to the photode-
tector via a BNC connector and to the electronic display
by a sub-miniature eight-pin DIN connector. The memory
module is separate from the power meter so that
photosensor and memory modules can be quickly
changed without opening up the electronic display. The
memory module may be separated from the photodetec-
tor to allow the photodetector to be used as an input
sensor to other common power meters or an oscillo-
scope.
Introduction
2.1
Photodetector
2.2
Memory
Module
2.3
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The Model 840-C is a 4-digit, ±9999 count autoranging
current meter with six DC current ranges, four AC current
ranges, and a photodetector. A simplified block diagram
of the Model 840-C is shown in Figure 2. The input
amplifier, a low noise current-to-voltage (I-V) converter,
buffers and amplifies the incoming signal. This stage is
followed by an A-D converter that digitizes the condi-
tioned analog input signal, providing information in a
form usable by the two microprocessors. The micropro-
cessors modify the data according to the wavelength
calibration information and then display the corrected
reading in subunits of watts.
Functional
Description
2.4
Figure 2 Simplified Functional Block Diagram
Also of importance are the DC and AC electrical charac-
teristics and conditions under which overload can occur.
Tables 1 and 2 present the electrical accuracy and
overload conditions for DC and AC signals respectively.
Note that final system accuracies are very detector and
use specific. More information can be found in Section
2.5 of this manual.
Analog
Output
AMP
A-D
MUX
x1
x10
AMP
Range
Resistors
Input
Amp
Peak
Detector
Tone
Generator Micro
Computers
Keypad
Display Driver
LCD Display
Detector
Cal
Module
818-ST
818-SL
818-UV
818-IR
E
2
PROM
Range Control
840 Controller
Analog
Output
MUX Ctrl
818-F-SL
818-F-IR
E
2
PROM
Photodiode
Detector
Photodiode
Detector
Beeper
Reset
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Table 1 DC Range Electrical Accuracy and Overload Conditions
Power Maximum Current Accuracy3
Range1Reading1,2 Range1±(%Rdg + %Full Scale)
18°C - 28°C
100.0 nW 99.99 nW 100.0 nA 0.5 + 0.054
1.000 µW 999.9 nW 1.000 µA 0.25 + 0.05
10.00 µW 9.999 uW 10.00 µA 0.25 + 0.05
100.0 µW 99.99 uW 100.0 µA 0.25 + 0.05
1.000 mW 999.9 uW 1.000 mA 0.25 + 0.05
5.00 mW 4.999 mW 5.00 mA 0.25 + 0.05
Notes:
1. Assuming detector response in the range 0.1 to 1.0 Amp/Watt. For
detector response smaller than 0.1 Amp/Watt, divide power range and
maximum reading by the ratio of the order of magnitude of the detector
response to 0.1. For example, if the detector response is 0.03 Amp/Watt,
divide power range and maximum reading by 0.01/0.1=0.1, so the ranges
will be from 1uW to 100mW.
2. Power above the maximum will result in “OLOL
OLOL
OL” display.
3. Electrical accuracy depends on current range. Detector calibration
accuracy usually limits reading accuracy.
4. Typical
Table 2 AC Range Electrical Accuracy and Overload Conditions1
Wave Frequency Accuracy2
Shape Range ±(%Rdg + %Full Scale)
18°C - 28°C
Sinewave 50 Hz – 1 kHz 1.0 + 0.1
Sinewave 1 kHz – 2 kHz 2.0 + 0.1
Sinewave 2 kHz – 5 kHz 5.0 + 0.1
Squarewave 50 Hz – 250 Hz 5.0 + 0.1
Squarewave 250 Hz – 2 kHz 1.0 + 0.1
Squarewave 2 kHz – 5 kHz 2.0 + 0.1
Notes:
1. Holds for powers at or above 10.00µW.
2 Electrical accuracy depends on current range. Detector calibration accuracy
usually limits reading accuracy.
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2.4.1 Input Amplifier
The input buffer amplifier provides signal gain for further
processing while simultaneously supplying the necessary
isolation between the input signal and the A-D converter.
The input buffer is composed of an inverting, low noise,
two stage, chopper stabilized amplifier chain. The first
stage gains are 20dB, 40dB, and 60dB. The second stage
gains are 1dB and 10dB. The amplifier gain is controlled
by the first microprocessor.
2.4.2 Microprocessors and Detector Cal Module (E2PROM)
The first microprocessor performs gain control and the
necessary calculation to convert from detector current to
optical power using the detector response data. This
data is stored in the Detector Cal Module and accessible
to the electronic controller through an eight-pin sub-mini
DIN connector.
In addition, a second microprocessor performs the
mathematical operations necessary to implement the
features of the Model 840-C such as BACKGROUND,dBm,
P-P and to drive the LCD display.
The microprocessor used is the Motorola MC68HC705C8
(with 8K PROM). Software for the microprocessor is kept
within the one-time-programmable read-only-memory
bundled on the microprocessor chip. Temporary storage
is provided by RAM that is internal to the microproces-
sor. This RAM is used to store calibration constants that
are read from the EPROM at power-up. It is also used to
store the reference power level and status flags for the
present mode of operation. This RAM is maintained in
sleep mode when the Model 840-C is turned off.
2.4.3 AC Wall Mount Adaptor
The Model 840-C may be operated off line power through
the use of the supplied AC Adaptor. This unit accepts AC
line power (mains power) and provides a DC voltage to
the Model 840-C through a 5.5mm diameter phone jack
(see schematic symbol at left).
CAUTION
Do NOT attempt to use the supplied AC Adaptor to
recharge any type of battery than the approved Ni-Cd
batteries for the Model 840-C. Doing so may damage
the batteries, the instrument, or both.
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