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Hartmann Wavefront Analyzer Installation & Setup Guide Ophir-Spiricon Inc. 60 West 1000 North Logan, UT 84321 For Sales, Service or Technical Support Phone (435)753-3729 Fax (435)753-5231 Email [email protected] Email [email protected] ©Copyright 2008, Ophir-Spiricon Inc., Logan, UT Document No 10892-001 Rev C 10892-001, Rev C i
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Page 1: Hartmann Wavefront Analyzer - ophiropt.com

Hartmann Wavefront Analyzer

Installation & Setup Guide

Ophir-Spiricon Inc. 60 West 1000 North

Logan, UT 84321

For Sales, Service or Technical Support Phone (435)753-3729 Fax (435)753-5231

Email [email protected] [email protected]

©Copyright 2008, Ophir-Spiricon Inc., Logan, UT Document No 10892-001 Rev C

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Contents

Contents .................................................................................................ii

Introduction........................................................................................... 1

1 Product Description.................................................................................1

2 Capabilities & Limitations .......................................................................2

Installation & Alignment ....................................................................... 4

3 Setting Up Your HWA Application and Computer Hardware ..................4 3.1 Unpacking ....................................................................................................... 4

3.1.1 Packing List.................................................................................................. 4 3.2 Installing the HWA Application........................................................................... 5 3.3 Installing the Spiricon Frame Grabber Card......................................................... 5 3.4 Preliminary System Checkout............................................................................. 5

3.4.1 Connecting the Sensor to the Computer ......................................................... 5 3.4.2 Start Up....................................................................................................... 6

3.5 Learning to Use the HWA Software .................................................................. 10 3.5.1 Using the On-line Help ................................................................................ 10

4 Optical Alignment..................................................................................10 4.1 Overview of the Optical Setup ......................................................................... 10

4.1.1 Alignment .................................................................................................. 11 4.1.1.1 Creating a Uniform Plane Wavefront..................................................... 12 4.1.1.2 Steps to Align the Sensor to the Incident Light ...................................... 14

4.1.2 Attenuation................................................................................................ 17 4.2 Laser Beam Wavefront Analysis ....................................................................... 18 4.3 Optical Component Testing ............................................................................. 22

Appendices .......................................................................................... 26 A Installing the Hartmann Wavefront Analyzer Application............................. 26 B Installing the Frame Grabber Card ........................................................... 27

B.1 Powering Up Your System for the First Time......................................... 29 B.2 Special Notes for Windows Millennium Users ........................................ 30

C Your Specific Wavefront Sensor ............................................................... 31

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Introduction

1 Product Description The Hartmann Wavefront Analyzer (HWA) from Spiricon is a wavefront sensor data analysis application with one or more integrated Hartmann wavefront sensors. Sensor data is quickly recorded and converted to wavefront information by the HWA application and displayed in an easy to use graphical interface. Hartmann-style optical tests employ a geometric method for measuring wavefront slopes at discrete points (sub-apertures) across the aperture of the sensor. The HWA application then reconstructs the wavefront falling on that aperture. Optical path differences (OPD) are easily determined from the reconstructed wavefront. This geometric method, as opposed to interferometric methods, has some advantages. For example, the HWA does not require a coherent light source, it is just as useful with white light as with monochromatic and it is insensitive to vibration. Your HWA will accomplish many of the tasks performed by:

1. Interferometers 2. Beam profilers

Your HWA will perform quantitative measurements for:

1. Surface metrology 2. Process monitoring 3. Optical testing 4. Beam analysis

The quantitative beam analysis can be performed for a wide range of lasers with wavelengths from 400nm to 1064nm, CW or pulsed. Intensity and phase of the wavefront are measured simultaneously. Fully customizable user selectable displays include:

1. Live Video 2. Intensity Distribution (2D or 3D) 3. Phase Distribution (2D or 3D) 4. Wavefront Slope Vector Plot

These displays may be printed or saved as Bitmaps for use in other applications. A text display of results for user selected calculations may include:

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1. Reconstructor Average Error. This is the average difference between the reconstructed wavefront slopes and the measured slopes.

2. Average Slopes (x direction, y direction) 3. RMS Slope (x direction , y direction) 4. Beam Centroid (This is the 1st moment in the x direction and the y

direction measured from the center of imager. Note that y increases going down, while x increases going to the right)

5. Beam Widths (x direction, y direction) This is the second moment based beam width ( )

yxdd σσ ,

6. Radius of Curvature of the Wavefront (x direction, y direction and average)

7. Fit Slopes (x direction, y direction) 8. Wavefront Minimum, Maximum and Peak to Valley (μm) 9. Wavefront RMS (μm), This is the rms measure of the phase of the

reconstructed wavefront, sampled at the subapertures. 10. Zernike Polynomial Coefficients for a user defined number of

polynomial terms. 11. Hermite Gaussian Mode Decomposition Percentages.

This text display is available to the clipboard for importing into other applications.

2 Capabilities & Limitations The HWA has a range of capabilities the limits of which depend on the particular HWA model and the wavelength of the light being used. Each sensor has a limit on the minimum and maximum radii of curvature that can be detected, the resolution of the intensity pattern falling on the sensor and the minimum wavefront spatial period. For an explanation of the terms in this section, see the Hartmann Wavefront Analyzer Tutorial. For the limits of your particular sensor see appendix C. Each sensor has a minimum radius of curvature that it can detect since a smaller radius of curvature would send the diffracted spot from one aperture beyond its allowed integration area on the camera CCD array. A maximum on the radius of curvature detectable is related to the diffracted spot radius, which depends on the wavelength and the sub-aperture sizes. It is also related to the resolution of the camera sensor and to the algorithms used to detect a slight change in the centroid location of the diffracted spot. If the radius of curvature is larger than this maximum, then for all intents and purposes the radius is infinite (zero curvature) as far as this sensor can measure.

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It is not possible for the intensity pattern falling on the sensor to be resolved any finer than the aperture spacing of the aperture array in the sensor. This spacing is also responsible for the limit on the wavefront spatial period. If the wavefront slopes change on a spatial frequency across the sensor that is greater than the spatial frequency of the apertures, then it will not be possible for the sensor to detect these fine details in the wavefront.

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Installation & Alignment

3 Setting Up Your HWA Application and Computer Hardware

3.1 Unpacking

3.1.1 Packing List Your HWA system will contain one or more of the following components. Refer to the packing list supplied with your system for actual components and quantities. HWA Documents

• Hartmann Wavefront Analyzer Installation & Setup Guide (this document), 10892-001 Rev B.

• Hartmann Wavefront Analyzer Tutorial, 10885-001 Rev E. Hartmann Style Sensor:

• HWA Sensor (Specially Modified CCD camera) • Sensor Power Supply1 • Camera to Frame Grabber Card Interface Cable • Camera to Frame Grabber Card BNC Cable • Spiricon LBA X00PC Frame Grabber Card [If you purchased a PC with

this instrument, the frame grabber card comes factory installed in the PC]

Computer System Components: • HWA Software Installation CD • Pentium® or higher PC running Windows® 95/98 or higher

Available Accessories

• ND filter set (1 inch) • Tip/Tilt Sensor Mount • Mirrors in Kinematic Mounts

Inspect all equipment for any damage that may have occurred during shipment. If any damage is found, contact the shipper and

Spiricon’s service department at: (435) 753-3729 1 Whether or not your sensor requires a separate power supply depends on the camera type that your sensor is based on.

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3.2 Installing the HWA Application Some systems will include a PC style computer pre-configured at the factory. The information in appendix A can be used to install the HWA application to computers not supplied by Spiricon. If your computer has been pre-configured at the factory, then you do not need to install the HWA application or the frame grabber card and should skip to section 3.4. If you need to install the HWA application in a computer system supplied by a source other than Ophir-Spiricon, refer to appendix A.

3.3 Installing the Spiricon Frame Grabber Card Some systems will include a PC style computer pre-configured at the factory. The information in appendix B can be used to install the frame grabber card in computers not supplied by Spiricon. If your computer has been pre-configured at the factory then you do not need to install the frame grabber card and should proceed to section 3.4. If you have installed the HWA application in a computer that will be used only off-line for analysis of previously recorded data, then you may skip this section and refer to the online help files available in the application. Any computer that will be connected directly to the HWA sensor requires a frame grabber card. To install a Spiricon frame grabber card in a computer not supplied by Spiricon refer to appendix B.

3.4 Preliminary System Checkout

3.4.1 Connecting the Sensor to the Computer Before mounting the sensor, set it on a secure flat surface, connect the cables from the sensor (camera) to the installed frame grabber card. This step is done to test the sensor camera before setting up the equipment. Many cameras and HWA sensors purchased from Spiricon are supplied with a camera power cable. This cable will provide camera power directly from the frame grabber card. Plug this cable into the appropriate 9-pin (female) connector on the frame grabber card, and into the camera or sensor. If a separate power supply is required, connect it according to the instructions provided with the sensor instead of

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connecting a camera power cable to the frame grabber card. Connect the BNC cable from the video output of the sensor to the frame grabber card. (See Figure 1). If you purchased a digital sensor and a frame grabber card with digital camera input, then instead of the BNC cable, a digital input cable connects the camera digital output to an adaptor cable which connects to the frame grabber card digital input. Some cameras come with an additional camera control cable, usually connected to the camera and a serial port on the computer. Use of this cable requires camera control software separate from the HWA software from Spiricon.

FRAME GRABBERCARD

PC StyleComputer

HWA Sensor

BNC Cable

PowerCable

PowerCable

BNC Cable Figure 1 Connect the sensor to the frame grabber card in the PC to perform the preliminary test.

3.4.2 Start Up Start the HWA application by double clicking the HWA icon or launch it using Start, Programs, Spiricon, HWA.

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You are now ready to make a preliminary test of the sensor. First click on the Setup menu.

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A tabbed dialogue box will appear.

Figure 2 Sensor Tab on the Setup Screen.

Check to make sure the camera type is correct for your sensor. If the camera type is correct, click on OK. Make sure that the instrument is stopped, the

instrument is stopped if there is a START button visible , don’t click the

START button. Click on Live Video. This is found on the Intensity window:

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Figure 3 Buttons found on the intensity window.

Remove any cover from the sensor. Check to see that lighting changes are registered on the screen.

Figure 4 Live Video display.

At low enough light levels you should see an array of bright spots on the screen in the Live Video window and you should be able to observe some changes as you aim the sensor at various light sources in the room or shade the sensor completely using the cover. If this is the case, then the basic function of the sensor is intact, and the preliminary system checkout is done. In normal room light, the sensor will not show the tidy array of diffracted spots. Instead, it will display a completely saturated state with a white area, but it will respond to changes in the light level, for example if you cover the sensor you will see the bright area dim, with spots possibly showing and then go dark. As long as you get this response, the sensor is working properly.

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3.5 Learning to Use the HWA Software An online User’s Guide provides all of the information required to learn how to use the HWA application. The online user’s guide is in an easy to navigate HTML format and describes the features and controls as well as some background information relevant to using the HWA application.

3.5.1 Using the On-line Help With the HWA application running, just click on the Help menu item.

in the menu bar at the top of the screen, and choose HWA Online Help from the drop down menu. Online Help consists of four chapters, Basic Principles and Conventions, User Interface, Optical Setup and Appendices. The chapter “Basic Principles and Conventions” covers the operating principles of the instrument and the theory behind wavefront analysis. It also covers the software conventions and the algorithms used in Spiricon’s HWA application. The second chapter, “User Interface”, describes the mechanics of navigating through the application including the various displays, options and settings. While using the application you should refer to the Online Help for any questions about how to use software features or what information is being displayed. Touch sensitive “Hints” and “What’s This” help features are also available. For hints, simply leave the cursor over a button or control for a few seconds and a hint will appear to describe what the button does. For “What’s This” help, click on the question mark on the tool bar and then click on the button or feature that you want to get help on. Spending a little time with the application using the features and controls is the best way to become familiar with and learn to use the HWA application and instrument.

4 Optical Alignment

4.1 Overview of the Optical Setup Your Hartmann Wavefront Analyzer is designed to measure, report and graphically display incoming optical wavefronts. Due to the limited dynamic range of the instrument, the incoming light or laser beam must be well aligned normal to the face of the sensor.

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4.1.1 Alignment To perform metrology (either laser or optical) with the HWA, it is necessary to align the sensor as accurately as possible to the incoming beam or light source. An absolute reference file for your sensor has been created at the factory using a large flat wavefront. When the optical alignment is correct, a measured flat wavefront can be observed. Spiricon suggests using a mechanical mount that allows the sensor to be tilted about the two axes parallel to the sensor face (pitch & yaw of the instrument). These kinematic mounts are available from almost every major optical equipment supplier. Furthermore, a pair of orthogonal translation stages that allows the beam to be positioned accurately on the sensor is also useful, or the beam can be positioned using a pair of front surface reflecting mirrors. Tilt of the sensor with respect to an incoming beam must be kept within the dynamic range of the instrument. In other words, the initial alignment of the instrument with the beam to be tested (or incoming light from an optic under test) is critical. We suggest using the retro-reflection from the sensor to do the rough alignment. If the beam falling on the sensor is reflected back through the optics to the source of the beam, then the alignment will be close. If you know that you have a flat wavefront input, then you can use the HWA application to make the fine adjustments on the tip, tilt and transverse location of the sensor. One feature of the application that is useful for rough adjustment is to use live video in the intensity window and right click on the space below the tools to bring up a menu allowing you to turn on the display of the integration areas. When you do this, you can observe the positions of the diffracted spots relative to their respective integration areas. Rough alignment can be done by adjusting the tip and tilt of the beam or instrument to center the spots in their integration areas.

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4.1.1.1 Creating a Uniform Plane Wavefront A uniform plane wave will often be desirable. This is the wavefront that will often be modified by optics to be tested (see section 4.3). This can be accomplished in several ways, two of which are described below.

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The simplest method for creating a flat wavefront is to use a point source and a collimating lens. This may be done with monochromatic or white light, note however, that wavelength dependent effects will be masked when using white light. A fiber-optic coupled diode laser can serve very well as a point source. A collimating lens is placed one focal length away from the output of the fiber optic. In order to get a nearly uniform illumination, the focal length should be large enough that the output angle of fiber optic, calculated from the numerical aperture by )arcsin(NAa =θ , has enough distance to over fill the lens. An aplanat lens is the best possible choice for making good reference wavefronts, but achromats or even plano-convex lenses can be used. In the case of achromats and plano-convex lenses it is usually best to face the least curved or flat side of the lens toward the point source. It is also desirable to use a lens with an F/# greater than 5. Final fine adjustment of the distance between the lens and the output of the fiber optic should be performed after the alignment is accomplished and the HWA instrument can be used to gauge the resultant wavefront curvature.

Collimating Lens

HWA Sensor

Fiber OpticOutput

Fiber CoupledLaser Source

Figure 5 A fiber optic coupled laser source acts as a point source. A collimating lens one focal length away gives plane wave output.

In lieu of a fiber optic point source, a laser focused on a pinhole aperture may be used. In this case, the size of the output plane wave will depend on the ratio of the collimating lens focal length to the focusing lens focal length and the size of the input laser beam.

Collimating Lens

HWA Sensor

PinholeAperture

Input Laser BeamFocusing Lens

Figure 6 A laser beam focused on a pinhole aperture can serve as a point source.

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Of course, mirrors can be used as is often done in infrared collimators, to obtain high quality flat wavefronts. The absolute reference file is used when performing either laser metrology or optical metrology with the Hartmann Wavefront Analyzer. Before a measurement can be made using the absolute reference file, the sensor must be aligned to the incident light. This can be difficult to do since the dynamic tilt range of these sensors can be as small as less than a degree depending on the sensor model, but by following the procedure below an accurate sensor alignment can be obtained quite reliably. Follow these steps to align the sensor:

4.1.1.2 Steps to Align the Sensor to the Incident Light Coarse alignment: • Roughly align the reflection of the incident light from the sensor back upon

itself. • Place an aperture in the beam that is illuminating the sensor as far away from

the sensor as possible. It is probably easiest to do this such that there are no optics between the aperture and the HWA sensor. The aperture does not have to be a complex optical component, a simple pinhole in an opaque material will do.

• Adjust the pitch and yaw of the sensor such that the light reflected from the aperture array passes back through the aperture.

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Figure 7 Adjust the Pitch and Yaw of the sensor until the reflection from the sensor goes back through the aperture in the card.

Now the coarse alignment is accomplished and you can use the HWA application to perform the fine adjustments to the alignment. Fine alignment: • Start the HWA software on your computer.

• Press “ ” to begin acquiring and processing frames. • Adjust the pitch and yaw of the sensor mount to minimize the average

wavefront slope by either monitoring the average slope value in the Results window or by monitoring the graphical wavefront slope representation in the Slopes window.

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Figure 8 Slopes window, you are trying to get displacement vectors as small as possible and fluctuating randomly instead of all in one direction as shown here.

• Once you are satisfied with the alignment, click the button to stop frame acquisition.

• Examine the Last Image Analyzed in the Intensity window.

• Figure 9 The Last Image Processed window is available in the intensity window. You should see a regular array of bright spots.

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• Overlay the integration areas by clicking on . • Look at the positions of the diffracted spots in the image. If the spots are

roughly in the centers of the integration areas, then you have achieved proper alignment. Because the optical wavefront can be converging or diverging, sometimes the diffracted spots can be centered in one part of the image and towards the edges as you move increasingly outward. In this case, the spots should be centered in the integration area boxes at the center of the image and possibly be closer to the edges of the integration areas as you move further from the center. If the diffracted spots touch or cross over the integration areas, you have exceeded the dynamic range of the sensor and cannot measure the incident wavefront.

4.1.2 Attenuation The HWA sensor is very sensitive to input light. Attenuation of the light source may be required in order to keep the intensity within the dynamic range of the HWA sensor. Bulk absorbing neutral density (ND) filters can reduce the light intensity and lessen the effects of room light, but they will introduce spurious wavefront errors. In some cases these errors may be compensated for by creating reference files with the ND filters in place. A better solution is to attenuate using front surface reflection, or attenuate the light source before the wavefront is shaped, for example attenuating the light going into a fiber optic before it emerges and is collimated by a lens. The saturation indicator,

, will alert you with a red light if the intensity is too high for making measurements. You should use enough attenuation to keep just below saturation.

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4.2 Laser Beam Wavefront Analysis Proper alignment of the laser beam to the sensor is critical. In all cases the beam should be very nearly perpendicular to the face of the sensor. Laser beam analysis requires the use of the Absolute reference file created at the factory. Sampling and attenuation of the laser beam must also be done with care not to severely distort the wavefront of the beam to be analyzed. This requires high quality mirrors or other optics with minimal distortion. It is usually a good idea to use a reflective type sampling of the laser beam using some type of beam splitter, such as Spiricon’s Beam Tap II shown in Figure 10, rather than directly shining the laser into the HWA sensor or requiring ND filters to provide all of the attenuation. This reflective sampling is usually the best preliminary attenuation of laser beam before analysis. Measurements should be done with the intensity just below the saturation level. The saturation indicator will alert you to an intensity above the optimum level for making measurements.

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Sam

pled

Bea

m

Input Beam

Figure 10 Schematic of Spiricon's Beam Tap II. An input beam is reflectively sampled resulting in a faithful, attenuated representation of the beam.

Coarse alignment should usually be performed with the sampler, such as the Beam Tap, in place but without the further attenuation of the ND filters. This way the beam reflected from the surface of the sensor is bright enough to be seen, and you are watching the reflection from the surface of the sensor and not from the surface of an ND filter. ND filters should be put into place before using the application to perform the fine adjustment.

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Figure 11 Use the 2nd mirror to get the retro-reflection from the surface of the sensor to go back into the source. Then the beam is normal to the surface of the sensor.

Figure 12 Use the 1st mirror to adjust the position of the beam (center it on the sensor) and then again use the 2nd mirror to get the retro-reflection back to the source. This way the beam is both centered on and normal to the sensor.

Adjustment should generally be done using a pair of mirrors as shown in Figure 11 and Figure 12. This is the easiest way to obtain the required angle and position of the beam. This pair of mirrors should usually be positioned after the sampler since too many reflections in the sampler are difficult to visualize and account for during adjustment of mirrors placed before the sampler. The two figures describe an iterative process, using the 2nd mirror to get the sampled laser beam normal to the surface of the sensor and then using the 1st mirror to adjust the centering of the beam on the sensor. Of course, each adjustment of one mirror creates the need to readjust the other until the coarse alignment is accomplished.

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Further attenuation will often be required and should include ND filters just before the sensor. This reduces the effect of ambient light and wavefront distortion that can be caused by ND filters. However, it may still be necessary to use further attenuation after the reflective sampler and before the final attenuation, in which case care should be taken to avoid distortion.

Figure 13 The whole system should consist of a reflective beam sampler, beam positioning mirrors and ND filter attenuation.

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4.3 Optical Component Testing Spiricon’s Hartmann Wavefront Analyzer can be used to test optical surfaces. Many configurations are possible for quantitative testing of optical components. Those arrangements shown here do not comprise an exhaustive list, but are presented to suggest just a few possibilities. Since many configurations will depend on it, the first consideration is how to create a point source. Two possible methods are shown in Figure 14.

HWA SensorLaser Source

EffectivePoint Source

Pinhole

HWA Sensor

Fiber CoupledLaser

Single ModeFiber

Figure 14 Two possible methods for creating a point source. Note: Your point source does not have to be a laser or monochromatic.2

Lenses may be tested as they are used to collimate your point source as shown in Figure 15.

2 When using white light, wavelength dependent results such as the times diffraction limit factor are not valid.

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HWA SensorPointSource

HWA SensorPointSource

Test Lens

Test Lens

AfocalRelay

Figure 15 The lens under test may be used as the collimating lens. A reference can be made using a known lens or by removing the lens under test and placing the point source far from the sensor or afocal relay and sensor combination. The afocal relay may or may not be required for your application.

Mirrors may be tested as shown in Figure 16, Figure 17 and Figure 18. The general rule is to create a flat wavefront with the test optic and observe the aberrations in comparison to the absolute reference file or to a relative reference file created using a similar setup.

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HWA Sensor

AfocalRelay

PointSource

Reference Mirror

Test

Mirr

or

Collimating Lens

Beam Splitter

Figure 16 Flat mirrors may be tested with or without a reference. Light from either the reference or the test mirror should be viewed. They should not be viewed simultaneously. Curved mirrors can also be tested in this configuration, again with or without a reference. In this case the point source may be placed at the focal point of the curved mirror and the collimating lens can be left out.

HWA Sensor

AfocalRelay

PointSource

Test Mirror Collimating Lens

Beam Splitter

Beam Expander

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Figure 17 Curved mirrors can be tested as they are used in a beam expander.

HWA Sensor

AfocalRelay

PointSource

Test Mirror

Beam Splitter

Figure 18 It is also possible to test curved mirrors by placing the point source at the focal point of the mirror. The afocal relay may not be required in your tests.

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Appendices

A Installing the Hartmann Wavefront Analyzer Application

If you purchased your HWA from Spiricon with a computer system and installation, then the HWA software and frame grabber card will already be installed and you can skip this Section. To install the LBA-PC Application Program in a Windows 95, 98, NT, 2000 or an XP system: (See special notes for 2000 system users.)

1. Start Windows.

2. Close all other Windows applications.

3. Place the Spiricon CD into your CD-ROM drive.

4. From the Taskbar, click on Start, then Run...

5. In the Open line type: R:\Spiricon\setup.exe <Enter> Where “R” is the letter of your CD-ROM drive.

6. Follow any directions that appear on your screen.

NOTE: After the installation is completed, you must exit and restart Windows before running the HWA program. Be sure to look at the HWA ReadMe text, before starting the HWA application. This will bring you up to date with any last minute information regarding the current version of the program.

__________________________________

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B Installing the Frame Grabber Card Any computer that will be connected to one of Ophir-Spiricon’s Hartmann Wavefront Analyzers requires a Spiricon frame grabber card. A frame grabber card is not required in a computer that will only be used to view HWA data collected on another computer. If your computer has been pre-configured at the factory, then the frame grabber card has already been installed and tested.

CAUTION

Electrostatic Discharge can result in permanent damage to electronic equipment. Always ground yourself by touching the system cabinet before beginning the following procedure. We strongly recommend using an anti-static wrist strap

attached to earth ground.

To install the frame grabber card: Disconnect the power to the PC and remove the cover as described in the computer’s technical manual. Locate PCI bus slots. Most PC’s will have 2, 3 or 4 PCI slots. Often, one will have a graphics card installed. Select an unused PCI slot and remove the rear filler plate associated with that slot. (See Figure 19)

Figure 19: PCI bus slots.

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Carefully plug the frame grabber card into the PCI slot. (See Figure 20) Make sure that it is fully seated in the PCI connector. Secure the end bracket with the screw that held in the filler plate.

Figure 20: Plug the frame grabber card into the PCI slot.

Do this step only if you purchased wavefront sensor based on a Digital Camera. To install the optional digital camera adapter, make sure that the slot immediately to the left (viewed from the front of the PC) of the above PCI slot is also empty, and remove its rear filler plate. If this slot is not empty then relocate the frame grabber card or the card that is occupying this slot. The digital camera adapter uses this rear panel opening, but does not plug into any of the PC expansion slots. Rather, it is provided with a short ribbon cable that plugs into the fame grabber card. (See Figure 21) Slide the digital camera adapter into the rear opening and plug its cable into the frame grabber card. Secure the adapter bracket to the rear panel with the screw that held in the filler plate.

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Figure 21: Optional digital camera adapter. Replace the cover and reconnect the A/C power to the PC.

B.1 Powering Up Your System for the First Time Computer systems pre-configured at the factory have been through the steps in this section. If Spiricon supplied your computer, you can skip to section 3.4. If you have installed the frame grabber card yourself it will automatically detected on startup. A new PCI device named LBA-PC will be automatically installed. This device will be found in the Device Manager under Sound, Video and Game Controllers. It is necessary to restart Windows after the installation procedure.

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B.2 Special Notes for Windows Millennium Users

Spiricon has successfully installed all of our Windows based applications in the Windows Millennium Edition environment and have seen no operating difficulties. We are however aware of a large number of ME users experiencing problems with the ME operating system. The range of difficulties being reported is too numerous for a serious discussion in this manual. We consider this to be part of the normal Windows operating system shakedown process, and that if you experience a good Windows ME installation on your PC, we would expect no further problems with loading and running our applications.

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C Your Specific Wavefront Sensor Model Number: ____________________________________________________ Serial Number: _____________________________________________________ Absolute Reference file: ______________________________________________ Original Setup File: __________________________________________________ Camera Type: _______________________________________________________ Aperture Array Wavelength: ___________________________________________ Aperture Array Subaperture pitch: (μm) __________________________________ Aperture Array Subaperture diameter: (μm) _______________________________ RMS wavefront error measured: (μm) ____________________________________ Calibration Date: _____________________________________________________

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Index achromats, 10 Align the Sensor, 11 Alignment, 3, 8 aplanat, 10 Attenuation, 14 Beam analysis, 1 Beam profiler, 1 Beam Width, 2 camera, 3, 4, 24, 25 Centroid, 2 Coarse alignment, 11, 16 Computer System, 3 digital camera adapter, 25 factory, 3, 4, 9, 15, 23, 25 fine adjustment, 10, 16 Frame Grabber Card, 3, 4, 23 Gaussian, 2 geometric method, 1 Hartmann Style Sensor, 3 Hartmann-style optical tests, 1 HWA Application, 3, 4, 22

Installation, 3 Intensity Distribution, 1 Interferometer, 1 Laser Beam Wavefront Analysis, 15 Live Video, 1 ND filter, 3, 16, 17 Online Help, 8 OPD, 1 Optical Alignment, 8 Optical Component, 18 Optical testing, 1 Phase Distribution, 1 Plane Wavefront, 10 Process monitoring, 1 Radius of Curvature, 2 Reconstructor, 1 Software, 3, 8 Surface metrology, 1 System Checkout, 4 Wavefront Slope, 1

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