干涉仪测量数据Three Flat ApplicationGuidelinesHardware Requirements- The following items are required two Transmission Flats(a andB)in bayonet mounts, a test flat(C), and a 2-Axis mount. If the test flat is unmounted, usea Self-centering Element Holder accessory. Either the Transmission Flat(B )or the test flat(C)must be rotated 180 degrees for the fourth measurement. A bayonet mountedtransmission flat, such as that used with Zygo interferometers, provides for easy rotationMeasurement sequence -Three flat testing requires three or four separate measurementsThree measurements provide absolute results along the vertical diameter, fourmeasurements also provide results along the horizontal diameter. Any measurement may berepeated before final calculations are made. Measurements can be completed in anysequence, but the sequence shown on page 1 involves the least handling of opticsPreparation1. Turn on the interferometer, start MetroPro, and open the application2. Click on the Aperture button untilApplication windowzygoit displays the aperture in useAperture Button-+t Sm Aperture3. Install Transmission Flat(B)in the interferometer accessory receptacle and align the flatPress the align/view button on the remote. Adjust the Tip/Tilt knobs on the accessoryreceptacle until the brightest spot is superimposed on the alignment crosshairsGP XPAccessoryReceptacle-Transmission日日Flat bRemote4. Press the Remote alignview button to switch back to the view mode. you should beable to see an image on the video monitor adjust the size of the image by pressing theRemote ZooM buttonspageThree Flat ApplicationPreparation(continued)5. Define a circular acquisition mask to include the flat but exclude the edges. Click theMask data button to open the mask editor To draw the mask, click circle, press the leftmouse button and drag the mouse over the image. The move or resize buttons are used tochange the location or size of the circle. Click the BG Inc button to change it to BG Excand the background is excluded. Click the Acq. button and then thc define button to dcfincthe mask. more information is located in the MetroPro Reference guide, under MaskEditor6. Define a fiducial over the flat as an alignment aid Click the Masks button in the maskEditor to switch it to the fiducial mode. To draw the fiducial, click Circle, press the leftmouse button and drag the mouse over the image. The move or resize buttons are used tochange the location or size of the circle. The fiducial should be centered within one pixel ofthe image. Close the Mask editor.7. Place a small triangular piece of tape onT ape on flat BFlat (b)aligned with the fiducial markFiducial aligned overUse the image shown on the videothe image of the flatmonitor as your guide8. Click the Calibrate button. Press the left mouse button and move the mouse to draw a lineacross the image area. The line should match up to some portion of the image for whichyou know the dimension release the mouse button and enter the dimension of the line inmillimeters and then press return. Close the calibrator window. Calibration establishesthe lateral measurement scale; without it, only wave units are displayed. For moreinformation, refer to"Calibration" in the metro Pro reference guideNote: Do not change the interferometer zoom setting, or many of the preparationsteps will have to be done overpage 4Three Flat ApplicationMaking MeasurementsAccessorySelf-centering ElementHolder(holds noGPI XPReceptaclemounted test flats)XISMountTransmission Transmission Test flat cFlat aFlat B+B A+c B+c B rotated +cTransmission flat180 degreesTest flatRemote侣日MeasurementsRegistration Block(taped to table)Controls3 for a vertical profile, 4MeasurementMeasurementType: 4 Measurementsto add a horizontal profileSelection ButtonsA+BA+BRotate: BSet to matchtell the software whatA+cASurface: C Surfacethe rotated flatmeasurement you are[B+CB+cperformingSelects the flatBR/CR BR/CRI Calculate[ce|」 profiles displayedStatus boxes display Click after alErases all"Done"after a measure- measurements are done measurem eentsment is completeto calculate profileresults1. Install Transmission Flat(a)into the interferometer accessory receptacle and align the flatPress the align/view button on the remote adjust the tip /tilt knobs on the accessoryreceptacle until the brightest spot is superimposed on the alignment crosshairs2. Place Flat(B)into the 2-Axis mount. Position the mount a short distance from theinstrument. Align the flat by adjusting the Tip/Tilt knobs on the 2-Axis mount until thebrightest spot is superimposed on the alignment crosshairs3. Press the remote align/view button to switch back to the view mode. The triangulartape on Flat B)should be aligned with the fiducial marks. Alignment is complete whenyou have a full aperture image and the Flat (b)reference marks align4. It is important to keep registration. It is recommended that you attach some type ofregistration blocks to the vibration isolation table after the system is aligned. a blockagainst the 2-Axis Mount provides a hard stop for positioning the mount after flats areswitchedpage5Three Flat ApplicationMaking Measurements(continued)5. Click the A+B button to match the test setup. Press Fl to measureNote: Multiple measurements of a test setup can be made until you obtain thebest possible data. You can track the measurement in the Process windowy making a Control Chart of the PV result. Stop measuring at a giventest setup when the pv result is stable and minimized6. Remove Flat(B) from the 2-Axis Mount and install Flat(c). align and null Flat(c), clickthe A+c button and press fl to measure7. Remove Flat(A)and install Flat(B)in the interferometer. Align Flat (B), align and nullFlat(C), click the B+C button, and press f1 to measure8. Remove Flat (B), rotate it 180 degrees, and reinstall it. Align Flat(B), align and null Flat(C), click the Br/CR button, and press fl to measur9. Click the Calculate button for final results on the three flats. To change which flat profilesare displayed, click the Surface button and then the calculate buttonSoftware Controls and ButtonsControls of interest for the Three Flat Application are listed For controls not listed, or forgrcatcr dctail, refer to the Metro Pro Reference guideControlFunctionTypeSelects the measurement type. Settings are 3 Measurements or 4Measurements. Three measurements provide a vertical profile; a fourthmeasurement also provides a horizontal profileRotateSpecifies the flat you plan to rotate 180 degrees for the BR/CRmeasurement. Settings are B or C, these refer to the flats used in the testYou must physically rotate the flat. a bayonet mounted Transmission FlatB)is easily rotated to rotate a test Flat(C), an indexing device is neededSurfaceSpecifies what surface to calculate and display. Settings are A, b, or cAfter a measurement series is complete the setting can be changed andresults redisplayed by clicking the Calculate buttonCommentUser entry for comments. Can be a company name, the person doing themeasurement, a comment on the test setup or other information. Entry islimited to 60 charactersPart NumberUser entry for part identificationPhase avgsSpecifies the number of phase averages to perform during measurements toimprove repeatability the default setting is opage 6Three Flat ApplicationSoftware Controls and Buttons(continued)ButtonFunctionA+BClick to select the current measurement. Transmission Flat(A)is on theinstrument, Transmission Flat ( B)is on the 2-Axis MountA+CClick to select the current measurement. Transmission Flat(A)is on theinstrument, the test Flat(C)is on the 2-Axis mountB+ cClick to select the current measurement. Transmission Flat(B)is on theinstrument, the test Flat(C)is on the 2-Axis MountBR/CRClick to select the current measurement. Either the Transmission flat (b)ortest Flat(C)must be rotated. The Transmission Flat(B)is on the instrument,the test Flat(C)is on the 2-Axis MountCalculateCalculates the vertical and horizontal cross-sections and draws the profileplots. Click after all measurements are completeClearErases all current measurement information. Click to start a newThree flat resultsResultDescriptionPVThe height between the lowest andthe highest point on the test partcuriarmsThe root-mean-square deviation of allpoints from a plane fit to thele software uses the following equations to derive the absolute surface data along thediametersFlatA=[(A+B)+(A+C)-(B+C)]/2Flatb=[(A+B)+(B+C)-(A+C)]/2Flat C=[(A+C)+(B+C)-(A+BJ/2pageThree Flat ApplicationOther OperationsOperationHow toPrintClick the word zygo in the window you want to print or select thePrint command from the window's menu Then click the printbutton in the print panelSaving changesYou must save the application under a new name. Select the Savemade to controls, plots, Application command from the Application Window menu. In theresults. and windowsFile Handler, enter a name for the file, ending with"app"andpress return. Then click the Done buttonTurn off the systemthe Quit command from the Metro Pro menu; turn off power ale ctWarning! Improper shutdown may damage the instrument. Sou have shut down from within WindowsTroubleshootingPossible cause and fixApplication not functional. The application is not licensed; contact ZYGO for licensinginformationThe hardware key is not installed. Install the hardware key andrestart the computerno data error orThe instrument is not properly focused or the fringes are notgraphic displays appear nulled. Focus the instrument and null the fringesincomplete or with holes. The Min Mod (%)control is set too high; decrease the valuePoor repeatabilityParts moving during measurement. Check part fixturingof resultsNoisy environment. Look at the video monitor for fringe drift orvibration; these signs indicate a noisy environment. Check for airdrafts; ensure that the computer is not contributing noise to thevibration isolation systemzAOygo corporationPhone(860)347-8506OMP-0387B1196Laurel brook roadF(860)347-8372Copyrightc 1996 Zygo CorporationP O. Box 448E-MailInquire(azygo.comZygo and the Zygo logo areMiddlefield. CT06455-0448WebSitehttp://www.zygo.comregistered trademarks ofof zygo corporation