Ocean Optics HR2000+ User manual

000-00000-000-02-A
HR2000+ High-speed Fiber Optic Spectrometer
Installation and Operation Manual
Document Number 294-00000-000-02-201012
Offices: Ocean Optics, Inc. World Headquarters
830 Douglas Ave., Dunedin, FL, USA 34698
Phone [phone]
Fax [phone]
8 a.m.– 8 p.m. (Mon-Thu), 8 a.m.– 6 p.m. (Fri) EST
E-mail: [e-mail] (General sales inquiries)
[email protected] (Questions about orders)
[e-mail] (Technical support)

Additional
Offices:
Ocean Optics Asia
666 Gubei Road, Kirin Tower, Suite 601B, Changning District, Shanghai,
PRC. 200336
Phone [phone]
Fax [phone]
E-Mail [e-mail]
Ocean Optics EMEA
Sales and Support Center
Geograaf 24, 6921 EW DUIVEN, The Netherlands
Phone [phone]
Fax [phone]
E-Mail [e-mail]
Regional Headquarters
Maybachstrasse 11
73760 Ostfildern
Phone [phone]
Fax [phone]
E-Mail [email protected]
Copyright © 2010 Ocean Optics, Inc.
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, by any means, electronic, mechanical,
photocopying, recording, or otherwise, without written permission from Ocean Optics, Inc.
This manual is sold as part of an order and subject to the condition that it shall not, by way of trade or otherwise, be lent, re-sold, hired out or otherwise
circulated without the prior consent of Ocean Optics, Inc. in any form of binding or cover other than that in which it is published.
Trademarks
All products and services herein are the trademarks, service marks, registered trademarks or registered service marks of their respective owners.
Limit of Liability
Every effort has been made to make this manual as complete and as accurate as possible, but no warranty or fitness is implied. The information provided is
on an “as is” basis. Ocean Optics, Inc. shall have neither liability nor responsibility to any person or entity with respect to any loss or damages arising from
the information contained in this manual.

294-00000-000-02-201012 i
Table of Contents
About This Manual......................................................................................................... iii
Document Purpose and Intended Audience.............................................................................. iii
What’s New in this Document ................................................................................................... iii
Document Summary.................................................................................................................. iii
Product-Related Documentation.................................................................................... iii
Upgrades....................................................................................................................... iv
Chapter 1: Introduction .....................................................................1
Product Overview .......................................................................................................... 1
System Requirements ................................................................................................... 2
EEPROM Utilization .................................................................................................................. 2
About SpectraSuite.................................................................................................................... 2
Sampling System Overview....................................................................................................... 2
How Sampling Works............................................................................................................ 2
Modular Sampling Accessories............................................................................................. 3
Interface Options ........................................................................................................... 3
Breakout Box ............................................................................................................................. 3
Shipment Components .................................................................................................. 4
Chapter 2: Installing the HR2000+ ....................................................5
Overview ....................................................................................................................... 5
HR2000+ Installation ..................................................................................................... 5
Configuring the HR2000+ with OOIBase32 .............................................................................. 6
Operator and Serial Number Dialog Box .............................................................................. 6
Default Spectrometer Configuration File............................................................................... 6
Configure Hardware Screen ................................................................................................. 6
Spectrometer Configuration Screen...................................................................................... 7
Connect Spectroscopic Accessories.............................................................................. 8
External Triggering Options ........................................................................................... 8

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ii 294-00000-000-02-201012
Chapter 3: Troubleshooting ..............................................................9
Overview ....................................................................................................................... 9
HR2000+ Connected to PC Prior to Software Installation .............................................. 9
Windows Operating Systems .................................................................................................... 9
Remove the Unknown Device from Windows Device Manager ........................................... 10
Remove Improperly Installed Files........................................................................................ 10
Mac Operating Systems ............................................................................................................ 11
Linux Operating Systems .......................................................................................................... 11
Older Version of OOIBase32 Installed ........................................................................... 11
Appendix A: Calibrating the Wavelength of the HR2000+ ..............13
Overview ....................................................................................................................... 13
About Wavelength Calibration ....................................................................................... 13
Calibrating the Spectrometer ......................................................................................... 14
Preparing for Calibration............................................................................................................ 14
Calibrating the Wavelength of the Spectrometer ...................................................................... 14
Saving the New Calibration Coefficients: USB Mode ..................................................... 16
Saving the New Calibration Coefficients: Serial Mode ................................................... 17
Appendix B: Specifications...............................................................19
Overview ....................................................................................................................... 19
How the HR2000+ Works .............................................................................................. 19
HR2000+ Components Table.................................................................................................... 20
HR2000+ Specifications ................................................................................................ 21
CCD Detector Specifications..................................................................................................... 21
HR2000+ Spectrometer............................................................................................................. 21
System Compatibility ..................................................................................................... 22
Compatibility for Desktop or Notebook PCs .............................................................................. 22
30-Pin Accessory Connector Pinout .............................................................................. 23
30-Pin Accessory Connector Pinout Diagram ........................................................................... 23
30-Pin Accessory Connector – Pin Definitions and Descriptions.............................................. 23
30-Pin J2 Accessory Connector - Part Numbers....................................................................... 25
HR2000+ 15-Pin Accessory Cable Pinout ..................................................................... 26
Index ...................................................................................................27

294-00000-000-02-201012 iii
About This Manual
Document Purpose and Intended Audience
This document provides the user of HR2000+ Spectrometer with instructions for setting up, calibrating
and performing experiments with their spectrometer.
What’s New in this Document
This version of the HR2000+ High-speed Fiber Optic Spectrometer, Installation and Operation Manual
updates information for the new triggering options for firmware versions 3.0 and above.
Document Summary
Chapter Description
Chapter 1: Introduction Contains descriptive information about the HR2000+
Spectrometer and how sampling works. It also provides a list
of system requirements, interface options, and shipment
components.
Chapter 2: Installing the HR2000+ Provides installation and configuration instructions.
Chapter 3: Troubleshooting Contains recommended steps to isolate and correct common
problems.
Appendix A: Calibrating the
Wavelength of the HR2000+
Provides instructions for calibrating the HR2000+
Spectrometers.
Appendix B: Specifications Contains technical specifications and connector pinouts for the
HR2000+ Spectrometers.
Product-Related Documentation
You can access documentation for Ocean Optics products by visiting our website at
http://www.oceanoptics.com. Select Technical → Operating Instructions, then choose the appropriate
document from the available drop-down lists. Or, use the Search by Model Number field at the bottom
of the web page.
Detailed instructions for SpectraSuite Spectrometer Operating Software are located at:
http://www.oceanoptics.com/technical/SpectraSuite.pdf.
Detailed instructions for the OOIBase32 Spectrometer Operating Software are located at:
http://www.oceanoptics.com/technical/ooibase32.pdf

About This Manual
iv 294-00000-000-02-201012
Detailed instructions for the Breakout Box are located at:
http://www.oceanoptics.com/technical/HR4_breakout.pdf.
Detailed instructions for External Triggering for firmware versions below 3.0 are located at:
http://www.oceanoptics.com/technical/external-triggering.pdf.
Detailed instructions for External Triggering for firmware versions 3.0 and above are located at:
http://www.oceanoptics.com/technical/external-triggering2.pdf.
Engineering-level documentation is located on our website at Technical → Engineering Docs.
You can also access operating instructions for Ocean Optics products from the Software and Technical
Resources CD that ships with the product.
Upgrades
Occasionally, you may find that you need Ocean Optics to make a change or an upgrade to your system.
To facilitate these changes, you must first contact Customer Support and obtain a Return Merchandise
Authorization (RMA) number. Please contact Ocean Optics for specific instructions when returning a
product.

294-00000-000-02-201012 1
Chapter 1
Introduction
Product Overview
The HR2000+ High-Speed Miniature Fiber Optic Spectrometer provides optical resolution as good as
0.035 nm (FWHM). The HR2000+ is responsive from 200-1100 nm, but the specific range and resolution
depends on your grating and entrance slit selections. With its capability of transferring 1ms spectra
continuously, the HR2000+ is the fastest spectrometer available from Ocean Optics.
The HR2000+ is perfect for applications where fast reactions need to be monitored and high resolution is
necessary, such as chemistry and biochemistry applications.
Data programmed into a memory chip on each HR2000+ includes wavelength calibration coefficients,
linearity coefficients, and the serial number unique to each spectrometer. Our spectrometer operating
software simply reads these values from the spectrometer — a feature that enables hot swapping of
spectrometers among PCs.
The HR2000+ Spectrometer connects to a notebook or desktop PC via USB port or serial port. When
connected to the USB port of a PC, the HR2000+ draws power from the host PC, eliminating the need for
an external power supply.
Ocean Optics HR2000+ High-speed Fiber Optic Spectrometer

1: Introduction
2 294-00000-000-02-201012
System Requirements
You can use the HR2000+’s USB connectivity with any PC that meets the following requirements:
Windows 98/Me/2000/XP operating system (or Windows CE 2.11 or later for handheld PCs)
Ocean Optics SpectraSuite or OOIBase32 software application installed and configured for use
with the HR2000+. See Chapter 2: Installing the HR2000+ for specific configuration
instructions.
Alternately, the HR2000+ has serial port adaptability for connecting to PCs, PLCs, and other devices that
support the RS-232 communication protocol. However, this connection method requires an external
power supply to power the HR2000+, the Breakout Box (HR4-BREAKOUT), and a serial cable.
EEPROM Utilization
An EEPROM memory chip in each HR2000+ contains wavelength calibration coefficients, linearity
coefficients, and a serial number unique to each individual spectrometer. The software application reads
these values directly from the spectrometer, enabling the ability to “hot-swap” spectrometers between PCs
without entering the spectrometer coefficients manually on each PC.
About SpectraSuite
SpectraSuite is the latest generation of operating software for all Ocean Optics spectrometers. It is a
completely modular, Java-based spectroscopy software platform that operates on Windows, Macintosh
and Linux operating systems. The software can control any Ocean Optics USB spectrometer and device,
as well as any other manufacturer’s USB instrumentation using the appropriate drivers.
SpectraSuite is a user-customizable, advanced acquisition and display program that provides a real-time
interface to a variety of signal-processing functions. With SpectraSuite, you have the ability to perform
spectroscopic measurements (such as absorbance, reflectance, and emission), control all system
parameters, collect and display data in real time, and perform reference monitoring and time acquisition
experiments. Consult the SpectraSuite manual for hardware requirements when using SpectraSuite (see
Product-Related Documentation).
Sampling System Overview
How Sampling Works
Ocean Optics components function in a sampling system as follows:
1. The user stores reference and dark measurements to correct for instrument response variables.
2. The light transmits through an optical fiber to the sample.
3. The light interacts with the sample.
4. Another optical fiber collects and transmits the result of the interaction to the spectrometer.

1: Introduction
294-00000-000-02-201012 3
5. The spectrometer measures the amount of light and transforms the data collected by the
spectrometer into digital information.
6. The spectrometer passes the sample information to SpectraSuite.
7. SpectraSuite compares the sample to the reference measurement and displays processed spectral
information.
Modular Sampling Accessories
Ocean Optics offers a complete line of spectroscopic accessories for use with the HR2000+. Most of our
spectroscopic accessories have SMA connectors for application flexibility. Accordingly, changing the
sampling system components is as easy as unscrewing a connector and replacing an accessory.
Interface Options
The HR2000+ has both USB and serial port connectors (with the use of an adapter), enabling you to
connect the spectrometer to a desktop or notebook PC via a USB port.
Computer
Interface
Operating System
Requirements Part Needed Description of Part
Desktop or
Notebook PC
via USB Port
Windows 98/Me/
2000/XP
USB-CBL-1
(included)
Cable that connects from USB port on HR2000+ to
USB port on desktop or notebook PC
Desktop or
Notebook PC
via Serial Port
Any 32-bit
Windows
operating system
HR4-
BREAKOUT
(not included)
Adapter block that enables connection from serial port
on HR2000+ to serial port on desktop or notebook PC;
comes with 5 VDC power supply (required when
connecting to serial port). User must supply own
software.
Breakout Box
Ocean Optics also offers the Breakout Box (HR4-BREAKOUT), a passive module that separates the
signals from their 30-pin port to an array of standard connectors and headers, enabling easy access to a
variety of features found in Ocean Optics’ HR2000+ Spectrometer. In addition to the accessory
connector, the breakout box features a circuit board based on a neutral breadboard pattern that allows
custom circuitry to be prototyped on the board itself.

1: Introduction
4 294-00000-000-02-201012
Shipment Components
The following information and documentation ships with the HR2000+ Spectrometer:
Packing List
The packing list is inside a plastic bag attached to the outside of the shipment box (the invoice
arrives separately). It lists all items in the order, including customized components in the
spectrometer (such as the grating, detector collection lens, and slit). The packing list also includes
the shipping and billing addresses, as well as any items on back order.
Spectrometer Installation Instructions
A sheet of paper that contains the information that you need to get your spectrometer system up
and running. Further information can be found on the Ocean Optics Software and Resources
Library CD (see below).
Wavelength Calibration Data Sheet
Each spectrometer is shipped with a Wavelength Calibration Data Sheet that contains information
unique to your spectrometer. SpectraSuite reads this calibration data from your spectrometer
when it interfaces to a PC via the USB port. Any other interface requires that you manually enter
the calibration data in OOIBase32 (select Spectrometer | Configure | Wavelength Calibration
tab). See the OOIBase32 documentation for more information (refer to Product-Related
Documentation for instructions on accessing OOIBase32 documentation).
Note
Please save the Wavelength Calibration Data Sheet for future reference.
Software and Technical Resources CD
Each order ships with the Ocean Optics Software and Technical Resources CD. This disc
contains software, operating instructions, and product information for all Ocean Optics software,
spectrometers, and spectroscopic accessories. You must have Adobe Acrobat Reader version 6.0
or higher to view these files. Ocean Optics includes the Adobe Acrobat Reader on the Software
and Technical Resources CD.
Ocean Optics software requires a password during the installation process. You can locate
passwords for the other software applications on the back of the Software and Resources Library
CD package.

294-00000-000-02-201012 5
Chapter 2
Installing the HR2000+
Overview
You must install the software application prior to connecting the HR2000+ Spectrometer to the PC. The
software installation installs the drivers required for HR2000+ installation. If you do not install the
software first, the system will not properly recognize the HR2000+.
If you have already connected the HR2000+ to the PC prior to installing the software, consult Chapter 3:
Troubleshooting for information on correcting a corrupt HR2000+ installation.
HR2000+ Installation
To connect the HR2000+ to a PC via the USB port, the PC must be running the Windows
98/ME/2000/XP operating system.
Note
The USB port on a PC can power up to five HR2000+ spectrometer channels. Systems
with more than five channels require a powered USB hub.
►Procedure
Follow the steps below to connect the HR2000+ to a PC via the USB port:
1. Install SpectraSuite on the destination computer.
2. Locate the USB cable (USB-CBL-1) provided with the HR2000+.
3. Insert the square end of the cable into the side of the HR2000+.
4. Insert the rectangular end of the cable into the USB port of the PC.
If you installed SpectraSuite prior to connecting the HR2000+, SpectraSuite installs the HR2000+ drivers.
If the drivers do not successfully install (or if you connected the HR2000+ to the PC before installing
SpectraSuite), consult Chapter 3: Troubleshooting.
If you have followed the previous steps and started SpectraSuite, the spectrometer is already acquiring
data. Even with no light in the spectrometer, there should be a dynamic trace displayed in the bottom of
the graph. If you allow light into the spectrometer, the graph trace should rise with increasing light
intensity. This means the software and hardware are correctly installed.
Note the spectrometer(s) that you have installed are listed in the Data Sources pane.

2: Installing the HR2000+
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Once you install the SpectraSuite software and the hardware, and establish your sampling system, you are
ready to take measurements.
Configuring the HR2000+ with OOIBase32
Once you install the HR2000+ with OOIBase32 software, you must configure OOIBase32’s Configure
Spectrometer options so that OOIBase32 recognizes the HR2000+ Spectrometer. Consult the
OOIBase32 Spectrometer Operating Software Operating Instructions for detailed instructions on
configuring the spectrometer in OOIBase32 (see Product-Related Documentation).
The following sections contain instructions on initially configuring the HR2000+ the first time you start
OOIBase32. Additional features are available for this spectrometer. See the OOIBase32 Spectrometer
Operating Software Operating Instructions for detailed information on these HR2000+ features.
Operator and Serial Number Dialog Box
The Operator and Serial Number screen prompts you to enter a user name and software serial number
into OOIBase32. Some data files created by OOIBase32 during sampling procedures use this information
in the file headers.
Default Spectrometer Configuration File
The Default Spectrometer Configuration File screen prompts you to select a spectrometer configuration
(.SPEC) file for use with the HR2000+. The unique serial number of the HR2000+ precedes the file
extension (for example, HR2A0162.SPEC).
Navigate to the OOIBase32 installation directory and select the spectrometer configuration file.
Configure Hardware Screen
The Configure Hardware screen prompts you to enter spectrometer-specific information into
OOIBase32 the first time you run the program. Typically, you need only enter this information the first
time you run OOIBase32. However, you can alter the hardware configuration at any time using the
Spectrometer Configuration screen. Select Spectrometer | Configure from the OOIBase32 menu bar
to access the Spectrometer Configuration screen.

2: Installing the HR2000+
294-00000-000-02-201012 7
►Procedure
To configure hardware in USB Mode:
1. Specify S2000 in the Spectrometer Type drop-down menu.
2. Specify HR2000+ in the A/D Converter Type drop-down menu.
3. Specify the serial number of the HR2000+ under the USB Serial Number drop-down menu.
Note
The system pre-fills this drop-down menu with the serial numbers of all discovered
HR2000+ Spectrometers.
4. Click the OK button to accept the selected options.
5. The spectrometer should now be able to acquire data and respond to light. Exit and restart
OOIBase32 to save configuration data to disk.
Spectrometer Configuration Screen
The Spectrometer Configuration screen prompts you to configure specific channel-level spectrometer
information, if necessary.
►Procedure
1. Select Spectrometer | Configure from the menu and set system parameters.
2. Select the Wavelength Calibration tab. OOIBase32 pre-fills the coefficients for the HR2000+
from information on a memory chip in the spectrometer.

2: Installing the HR2000+
8 294-00000-000-02-201012
3. Verify that the calibration coefficients match the coefficients from the Wavelength Calibration
Data Sheet that accompanied the spectrometer. If necessary, modify these values using the USB
Programmer utility.
4. Additionally, ensure that you select both the Master and Channel Enabled boxes.
5. In the A/D Interface tab, enter the same values as in the Configure Hardware screen.
OOIBase32 stores this information for future use once you close the program.
Connect Spectroscopic Accessories
To find operating instructions for HR2000+-compatible products (such as light sources, sampling
chambers, and probes), consult the Software and Technical Resources CD or the Ocean Optics website at
http://www.oceanoptics.com/technical/operatinginstructions.asp.
External Triggering Options
You can trigger the HR2000+ using a variety of External Triggering options through the 30-pin
Accessory Connector on the spectrometer. For HR2000+ firmware versions below 3.0, see the External
Triggering Options document located at http://www.oceanoptics.com/technical/external-
triggering.pdf. For HR2000+ firmware version 3.0 and above, see the External Triggering Options
document located at ???. The triggering document contains instructions for configuring External
Triggering options for the HR2000+.

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Chapter 3
Troubleshooting
Overview
The following sections contain information on troubleshooting issues you may encounter when using the
HR2000+ Spectrometer.
HR2000+ Connected to PC Prior to Software
Installation
Windows Operating Systems
If you connected your Ocean Optics USB device to the computer prior to installing your Ocean Optics
software application, you may encounter installation issues that you must correct before your Ocean
Optics device will operate properly.
Follow the applicable steps below to remove the incorrectly installed device, device driver, and
installation files.
Note
If these procedures do not correct your device driver problem, you must obtain the
Correcting Device Driver Issues document from the Ocean Optics website:
http://www.oceanoptics.com/technical/engineering/correctingdevicedriverissues.pdf.

3: Troubleshooting
10 294-00000-000-02-201012
Remove the Unknown Device from Windows Device Manager
►Procedure
1. Open Windows Device Manager. Consult the Windows operating instructions for your computer
for directions, if needed.
2. Locate the Other Devices option and expand the Other Devices selection by clicking on the "+"
sign to the immediate left.
Note
Improperly installed USB devices can also appear under the Universal Serial Bus
Controller option. Be sure to check this location if you cannot locate the unknown device.
3. Locate the unknown device (marked with a large question mark). Right-click on the Unknown
Device listing and select the Uninstall or Remove option.
4. Click the OK button to continue. A warning box appears confirming the removal of the Unknown
Device. Click the OK button to confirm the device removal.
5. Disconnect the HR2000+ from your computer.
6. Locate the section in this chapter that is appropriate to your operating system and perform the
steps in the following Remove Improperly Installed Files section.
Remove Improperly Installed Files
►Procedure
1. Open Windows Explorer.
2. Navigate to the Windows | INF directory.
Note
If the INF directory is not visible, you must disable the Hide System Files and Folders
and Hide File Extensions for Known File Types options in Windows Folder Options.
Access Windows Folder Options from Windows Explorer, under the Tools | Folder
Options menu selection.
3. Delete the OOI_USB.INF in the INF directory. If your computer is running either the Windows
2000 or XP operating system, you must also delete the OOI_USB.PNF file in the INF directory.
4. Navigate to the Windows | System32 | Drivers directory.
5. Delete the EZUSB.SYS file.
6. Reinstall your Ocean Optics application and reboot the system when prompted.

3: Troubleshooting
294-00000-000-02-201012 11
7. Plug in the USB device.
The system is now able to locate and install the correct drivers for the USB device.
Mac Operating Systems
Since there are no device files for the USB2000-FLG Spectrometer in a Mac operating system, you
should not encounter any problems if you installed the spectrometer before the SpectraSuite software.
Linux Operating Systems
For Linux operating systems, all you need to do is install the SpectraSuite software, then unplug and
replug in the spectrometer. Technically, the driver files for Linux simply give nonprivileged users
permission to use newly connected hardware. There isn’t any long-term harm to plugging in the device
before installing the software.
Older Version of OOIBase32 Installed
If the PC to be used to interface to your HR2000+ already has an older version of OOIBase32 software
installed, you must install the latest version of OOIBase32. You can download the latest version of
OOIBase32 from the Ocean Optics website at
http://www.oceanoptics.com/technical/softwaredownloads.asp.
You do not need to uninstall previous versions of OOIBase32 when upgrading to the latest version.

3: Troubleshooting
12 294-00000-000-02-201012

294-00000-000-02-201012 13
Appendix A
Calibrating the Wavelength of
the HR2000+
Overview
This appendix describes how to calibrate the wavelength of your spectrometer. Though each spectrometer
is calibrated before it leaves Ocean Optics, the wavelength for all spectrometers will drift slightly as a
function of time and environmental conditions. Ocean Optics recommends periodically recalibrating the
HR2000+.
About Wavelength Calibration
You are going to be solving the following equation, which shows that the relationship between pixel
number and wavelength is a third-order polynomial:

p= I+ C1 p+ C2 p2+ C3 p3
Where:
 = the wavelength of pixel p
I= the wavelength of pixel 0
C1= the first coefficient (nm/pixel)
C2= the second coefficient (nm/pixel2)
C3= the third coefficient (nm/pixel3)
R= the reference intensity at wavelength 
You will be calculating the value for Iand the three Cs.

A: Calibrating the Wavelength of the HR2000+
14 294-00000-000-02-201012
Calibrating the Spectrometer
Preparing for Calibration
To recalibrate the wavelength of your spectrometer, you need the following components:
A light source capable of producing spectral lines
Note
Ocean Optics’ HG-1 Mercury-Argon lamp is ideal for recalibration. If you do not have an
HG-1, you need a light source that produces several (at least 4-6) spectral lines in the
wavelength region of your spectrometer.
An HR2000+ spectrometer
An optical fiber (for spectrometers without a built-in slit, a 50-m fiber works best)
A spreadsheet program (Excel or Quattro Pro, for example) or a calculator that performs third-
order linear regressions
Note
If you are using Microsoft Excel, choose Tools | Add-Ins and check AnalysisToolPak
and AnalysisTookPak-VBA.
Calibrating the Wavelength of the Spectrometer
►Procedure
Perform the steps below to calibrate the wavelength of the spectrometer:
1. Place the software into Scope mode and take a spectrum of your light source. Adjust the
integration time (or the A/D conversion frequency) until there are several peaks on the screen that
are not off-scale.
2. Move the cursor to one of the peaks and position the cursor so that it is at the point of maximum
intensity.
3. Record the pixel number that is displayed in the status bar or legend (located beneath the graph).
Repeat this step for all of the peaks in your spectrum.
4. Use the spreadsheet program or calculator to create a table like the one shown in the following
figure. In the first column, place the exact or true wavelength of the spectral lines that you used.
In the second column of this worksheet, place the observed pixel number. In the third column,
calculate the pixel number squared, and in the fourth column, calculate the pixel number cubed.