OPHIR BeamSquared User Manual Download

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Step Size and Start/Stop Selection

2.6

After the system is properly aligned and attenuated, perform an initial run (see section 4.2.1).

Select a step size that is approximately one tenth
of the focal length of the lens in use. Use the
default start and stop values.

Allow the run to complete. Take note of the data
point nearest the waist. About 230mm in the
graph shown.

Begin a second run with the Z Start and Stop
values being equidistant around the value found
in step 2.

Summary of Contents for BeamSquared

Page 1: ...ows 7 and Window 10 64 BIT For Sales Service or Technical Support Phone 435 753 3729 Fax 435 753 5231 Service Email service us ophiropt com Sales Email sales us ophiropt com Ophir Spiricon LLC 3050 North 300 West North Logan Utah 84341 2019 Ophir Spiricon LLC ...

Page 2: ...o come As a valued customer your comments and opinions are always very important to us If you have any concerns questions or comments bring them to our service department s attention We are ready to help with everything from basic setup to working with you to find solutions for your most complex photonics measurement needs Thank you once again for your business and please let us know if we can be ...

Page 3: ...erate the BeamSquared system Chapter 4 Operation Details the operating modes and how to use the BeamSquared System Chapter 5 M2 Theory and Tutorial Presents a tutorial on M2 theory practical insights behind the propagation measurements and the ISO measurement methods and a description of the features in the BeamSquared software Chapter 6 M2 Computations Contains computational information on how M2...

Page 4: ...Indicates warning information Failure to follow instruction may result in harm to the user or product damage Indicates that the instruction refers to operating BeamSquared in Manual Mode ...

Page 5: ...e BeamSquared for Operation 18 2 3 Mount the Optical Train 18 2 3 1 Install the Camera 19 2 3 2 Connect BeamSquared 20 2 3 3 External Attenuation of the Beam 21 2 4 Attenuation 22 2 4 1 Beams 1 Watt 22 2 4 1 1 Beams 400 Watts 22 2 4 1 2 Beams 2000 Watts 22 2 4 1 3 Beams 2000 Watts 22 2 4 1 4 Beam Alignment and Setup for Auto Mode 22 2 5 Distance from Laser 23 2 5 1 Initial Setup and Rough Beam Ali...

Page 6: ...ow 32 3 2 1 TIFF Image Format 33 3 2 1 1 Exporting TIFF Images for use with HDF5 33 3 2 1 1 1 Show Hide Ribbon Bar 34 3 2 2 Ribbon Group Visibility 34 3 2 3 Run Ribbon 35 3 3 Live Playback 35 3 3 1 Start 35 3 3 2 Configure 35 3 3 3 Info 35 3 3 4 Mode 36 3 3 5 Boundary Check 36 3 3 6 Real Time M2 36 3 3 7 Load and Save 36 3 3 8 Abort Run 37 3 3 9 Finish Run 37 3 3 10 Table Ribbon 37 3 4 Rail 37 3 4...

Page 7: ...bility 51 3 7 6 Interface Customization 53 3 8 Docking Handles 53 3 8 1 Chapter 4 Operation 54 Operating Modes 54 4 1 Automated Stepping 54 4 1 1 Automated ISO Setup 54 4 1 2 Four Cuts Method 55 4 1 3 When to use the Four Cuts method 56 4 1 3 1 Four Cuts on Two Axes 56 4 1 3 2 Step Table 57 4 1 4 Real Time M2 Mode 57 4 1 5 BeamSquared Operation 58 4 2 Configuration Wizard 58 4 2 1 Step by Step Wiz...

Page 8: ...lectro Mechanical Operation 77 5 7 Data Collection 78 5 8 Chapter 6 M2 Computations 79 Curve Fitting 79 6 1 M2 K Factor and BPP 79 6 1 1 Translation Equations 79 6 1 2 Full Divergence Angle 79 6 1 2 1 Waist Width 80 6 1 2 2 Waist Location 81 6 1 2 3 Waist Location Relative to Principal Plane 81 6 1 2 3 1 Waist Location Relative to Laser Aperture 82 6 1 2 3 2 Rayleigh Range 82 6 1 3 Astigmatism and...

Page 9: ... Step Wizard 99 9 3 4 Exposure 101 9 3 5 Appendix A Lens Calibration Adjustments 102 A 1 Plano convex Lens Calibration 102 A 2 Refractive Index of Common Lens Materials 103 Appendix B Warranty 104 Appendix C BeamSquared Supported Cameras 105 Appendix D Camera Information 106 D 1 SP300 106 Supplied Accessories 106 D 1 1 External Trigger Control 106 D 1 2 GPI O Connector Description 106 D 1 3 D 2 SP...

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Page 11: ...Unless the laser s optical path is enclosed the operator should protect against accidental exposure Exposure to personnel other than the operator must also be considered Hazards include direct beam exposure and reflected radiation When working with an unenclosed beam path it is advisable to do so while the laser is powered down or at reduced power levels Whenever there is a risk for dangerous expo...

Page 12: ...license for BeamSquared Automated BeamSquared Models 1 2 2 Part Number Model Number Description SP90443 BSQ SP300 SP300 camera and license with BeamSquared hardware SP90502 BSQ SP920 SP920 camera and license with BeamSquared hardware SP90444 BSQ XC130 XC 130 camera and license with BeamSquared hardware SP90445 BSQ A BeamSquared hardware accessory model sold without a camera for customers that alre...

Page 13: ... different wavelength regions spot sizes and divergences Five lenses are included with the SP300 and SP920 systems and two lenses with the XC 130 system See below for nominal focal lengths Additional lenses must be ordered separately BSQ SP300 BSQ XC130 BSQ SP920 BSQ A Included Lenses 266 440nm UV 500mm FL 430 700nm VIS 500mm FL 430 700nm VIS 400mm FL 650 1000nm NIR 400mm FL 1000 1550nm NIR extend...

Page 14: ...hile it may be that the laser input power or energy density measures well below this damage threshold it can easily exceed these levels when focused onto the camera sensor Use caution and err on the side of safety CCD cameras are costly to repair or replace General Accuracy 5 typical Note Accuracy can be degraded by a variety of situations consult text Measurement Cycle Time 1 minute typical depen...

Page 15: ...BeamSquared Optical Train Dimensions 1 4 ...

Page 16: ...l to achieve the highest possible measurement accuracy Automated BeamSquared Required Equipment A PC computer running Windows 7 or Windows 10 BeamSquared hardware A SP300 SP920 or XC 130 camera A laser beam attenuation device Automated BeamSquared Optional accessories One pair of beam steering mirrors Manual BeamSquared Required Equipment A PC computer running Windows 7 or Windows 10 A Pyrocam IV ...

Page 17: ...with Administrator privileges 1 If the computer is setup to Auto Play DVDs do the following a Insert the supplied DVD into the DVD drive and wait for the Ophir Spiricon Software Auto Install screen to appear b Click on the Software Install button c Follow the directions that appear on the screen 2 If the computer does not have the Auto Play feature enabled a Insert the supplied DVD into the DVD dr...

Page 18: ...eds 2 Place the input aperture on the same plane as the laser beam 3 Allow enough space around the BeamSquared hardware to direct the laser beam through the input aperture 4 Secure the optical train to the optical table with the provided mounting clamps An example of a typical setup can be seen below The turning mirrors shown are optional accessories that are critical to alignment The center of th...

Page 19: ...ctive dust cover 3 Thread the C mount insert into the camera Take care not to cross thread the components Keep the camera face down as you attach the threaded insert to prevent dust from contacting the imager 4 Insert the camera completely into the optical train and re secure the screw on the camera mounting clamp Orientation of the camera is not critical at this point and will be covered more in ...

Page 20: ...indows Start button 6 When the optical train initializes the translation table and attenuator cycle the entire range of motion confirming the table and attenuator are fully operational and then sets them to the home locations Only connect one Ophir Spiricon device at a time If multiple devices are connected to a single PC the camera or other components may not connect correctly The M2 200 and M2 2...

Page 21: ...ches the camera changes potentially over several orders of magnitude during a measurement cycle This is a result of the camera effectively moving from a large unfocused spot near the lens into and through the focus at the waist then out again to an unfocused spot see diagram below During a regular run the optical train automatically adjusts to accommodate these changes in beam intensity so long as...

Page 22: ...e LBS 300s system Do not exceed 2MW cm2 or 50 Joules cm2 10 nanosecond pulse width This fluence will damage most beam sampling splitting optics Beams 2000 Watts 2 4 1 4 Beams with power greater than 2000 Watts require custom cooled beam sampling optics Alternatively Ophir Spiricon s BeamWatch line of laser beam diagnostic products does not require any beam attenuation Beam Alignment and Setup for ...

Page 23: ... natural beam waist and the lens should be between one third and three times the focal length of the lens This distance is the sum of Lasera Laserb and Laserc in the graphic on the right In this example the natural beam waist is located at the laser source faceplate See section 6 1 7 for computations The distance from the reference datum to the lens is approximately 95 5mm The actual value is cali...

Page 24: ...irror 2 on the optical axis of the BeamSquared with both mirrors in line with each other Laser Mounting Height 2 5 2 3 Where possible the height of the laser source should be set to the same height as the optical train s optical axis This makes centering the beam easier as adjustments to the steering mirrors X and Y tilt adjustments have similar axial effects Otherwise a change in one mirror s X a...

Page 25: ...the center of the laser beam and the tip of the shadow are aligned on the pinhole the beam is aligned with the optical axis of the unit see section 2 5 3 3 Use the alignment mirrors to adjust the beam direction until it passes over the sight and into the pin hole Alternate adjustments between mirror 1 and 2 Mirror 1 to center over the sight and mirror 2 to center over the pinhole ...

Page 26: ...ately 75 of camera saturation 7 Use the translation controls on the Rail panel under the Table ribbon bar to change the Z location of the camera 8 Watch the motion of the beam as the table moves between rail positions A and B The beam image should stay fairly centered in the camera array without wandering significantly Precision Beam Alignment 2 5 3 If the beam does not remain centered as the tabl...

Page 27: ... to lose track of the beam Ghost Beams 2 5 3 1 The optical path design of the BeamSquared system creates some natural reflections of the input laser While most ancillary reflections are orders of magnitude below detection levels the secondary and tertiary reflections of the input laser land near but outside of the camera aperture and can be detected and aligned to if the user is unaware of them Th...

Page 28: ...image to the right the asymmetrical beam is poorly aligned with the camera axes Unless the beam is circular axial alignment is critical to obtain accurate results ISO states that when the ratio of the beam widths exceeds 0 87 the beam can be considered circular For the beam shown the profile is tilted approximately 45 degrees from the axes of the window The calculations assume a nearly circular be...

Page 29: ...elect a step size that is approximately one tenth of the focal length of the lens in use Use the default start and stop values 2 Allow the run to complete Take note of the data point nearest the waist About 230mm in the graph shown 3 Begin a second run with the Z Start and Stop values being equidistant around the value found in step 2 ...

Page 30: ...on This chapter describes the various control features available in BeamSquared beginning with the terminology used to identify the basic control forms Title Bar 3 1 1 The topmost bar on the application Contains from left to right System Menu button Gives access to window controls Quick Access Toolbar The buttons shown here are Live Playback and Start Application Information Application name versi...

Page 31: ...in all common control items Panels 3 1 4 Panels contain buttons drop down lists edit controls etc Tool tips are available on most all controls hover the mouse to view Display Area 3 1 5 The display area consists of all docked display windows Each display can be disabled resized docked or floated to any location on the screen The content of the display area is explained more in section 3 8 Status B...

Page 32: ...ata extension Recent Stores quick links to recent data files Options Allows customization of the color scheme of the user interface Choose a combination of a light or dark theme a primary color and secondary color Select apply theme to accept changes Reset Layout allows you to restore the windows to the default configuration Enable Export frame data as TIFF to save images in a tiff format see sect...

Page 33: ... normalized floating point value between 1 and 1 The value is calculated using the minimum and maximum values of a signed 32 bit integer namely 2 147 483 647 The original per pixel values of the collected data can be obtained by multiplying the floating point value obtained from the tiff image by 2 147 483 647 Exporting TIFF Images for use with HDF5 3 2 1 1 1 TIFF images can be exported for use wi...

Page 34: ... caret icon to display or hide the ribbon bar or double click a tab as referenced in section 3 1 2 Ribbon Group Visibility 3 2 3 Located below the Windows Close button is the Ribbon Group Visibility configuration A dialog box opens that allows turning on or off ribbon panels Select the tab of the ribbon to view and select the slider to turn the panel on or off ...

Page 35: ...on such that the dynamic range of the camera is utilized Start 3 3 2 Use Start to begin an M2 run with the last programmed or loaded settings View or change the settings in the Configuration wizard accessed through the Configure button Configure 3 3 3 Use Configure to open the Configuration wizard input information about the system under test select the operating mode Automated Stepping Automated ...

Page 36: ...Real Time M2 to start real time monitoring Click again to disable and return to normal operation See section 4 1 5 for information on running in Real Time M2 mode Load and Save 3 3 8 Select Load to open a saved run setup file bsqSetup Loaded files display the run and configuration setup from the saved file Select Save to preserve the current run setup in a file Saved files contain the configuratio...

Page 37: ...800mm The start point of the table varies slightly between BeamSquared units The start point or A location is set and calibrated at the factory as the Z Fixture value and cannot be changed Rail 3 4 1 This panel allows you to control the location of the optical train The Previous button moves the table to the A location and the Next button moves the table to the B location Drag and drop the slider ...

Page 38: ...is panel displays the settings of the currently inserted lens The values are informational and cannot be changed Source Ribbon 3 5 The Source ribbon contains controls that vary by camera Data Source 3 5 1 Camera BeamSquared not Connected Camera BeamSquared Connected Just Camera Connected On startup BeamSquared automatically connects to the first BeamSquared licensed camera found If a camera is plu...

Page 39: ...tors respond linearly to monochromatic light For linearly responding cameras the Gamma setting should be set to 1 For cameras that employ phosphors or other wavelength conversion materials the gamma of the material should be entered here to convert the nonlinear response back to a linear one Ophir Spiricon s Phosphor coated cameras require Gamma to be set to 1 95 Trigger 3 5 4 The SP300 XC 130 and...

Page 40: ...one of two different chopping rates 25Hz and 50Hz 50Hz is recommended in order to receive good response linearity 25Hz should only be used in combination with an increased gain setting to extract the images of beams with extremely weak intensities In pulsed mode the Pyrocam must be externally triggered and the delay value for the pulse width should be set slightly longer than the laser pulse Refer...

Page 41: ...enabled results data from Laser After Lens and every frame from the run Report 3 6 2 Generate PDF Report The report feature generates a PDF file with data from the previous run The report includes information entered in the Configuration wizard and all enabled results in the Laser and After Lens groups Results from all other groups are not included Reports also display a 3D Profile along with an a...

Page 42: ...Single Run Report In the report shown the first point has been manually removed and the third and seventh points have been automatically removed These data points are not included in the M2 calculations ...

Page 43: ...Multi Run Report A Multi Run Report displays the statistics for the run as well as all information found in the Single Run Report ...

Page 44: ...sor The units follow the width units selected in the Results Settings see section 3 7 5 1 The Intensity bottom displays the pixel value in digital counts at the cursor location The color palette drop down top left displays color palette options for the beam profiles Palettes are designed to work with a variety of laser safety eye wear Measured Caustic Display 3 7 2 The Measured Caustic Display win...

Page 45: ... 3D Beam Display provides a 3D representation of the beam made up of the frames taken during a run Each slice represents a data point in the Measured Caustic Display plot Left click and drag anywhere in the display to rotate the image Right click and drag anywhere in the display to pan the image Zoom in and out by scrolling forward or back on the mouse respectively Select any point in the Measured...

Page 46: ...e Source ribbon or step through the Configuration wizard by clicking Configure When a run is completed the wizard closes If the window is closed before the run is finished or aborted it can only be reopened with the Run Steps button For more information on the Step by Step wizard refer to section 4 2 2 ...

Page 47: ... only appear when operating in their respective modes Enable or disable results items by selecting the Results drop down at the top of the window The next to the group heading enables or disables all results in the group Hover over a group heading to open the list of all items in that set Select an item to enable disable it Results can also be disabled by hovering the mouse on the result item and ...

Page 48: ... scale value of the camera used when the frame was generated Bits per Pixel The bits per pixel of the camera used when the frame was generated Total The sum of the digital counts of all of the pixels within the aperture represents the intensity of the beam Average Pwr Density The total beam intensity divided by the cross sectional area Peak The digital count of the pixel with the highest intensity...

Page 49: ... Twist is active The computed ratio of the major and minor beam widths of an elliptical beam Beams with Ellipticity greater than 87 are considered circular by ISO standards Orientation Only active when Beam Twist is active The angle between the horizontal axis of the camera and the major axis of an elliptical beam Can be negative or positive Beam Twist The rotational change in orientation for an e...

Page 50: ...tability window is open an extra set of results become visible in the Results window section 3 7 6 Center The coordinate position of the centroid of the histogram Azimuth The angular direction of movement Δx Δy The computed 4σ of the displacement positional result along the X Y direction of the azimuth angle orthogonal to the axis of the azimuth and radially when the distribution of the motion is ...

Page 51: ... desired units for calculating width results distance results and angle results Changing the width and distance units also updates the Measured Caustic Display axes BeamSquared obtains the lens focal length and other lens information from a RFID feature that is integrated into the lens holder If the system is operated at a different wavelength than where the lens was measured the software automati...

Page 52: ...t are specific to this window Reset Clears the chart and results Save Opens Windows Explorer to select a location to save a csv file of the results Load Opens Windows Explorer to load a previously saved chart file If the lens is inserted a yellow bar displays above the chart space meaning that Positional Stability cannot be run Once the lens is removed the bar disappears and Positional Stability c...

Page 53: ...mple the Measured Caustic Display window is being dragged Drag the display over one of the dock handles and release to place the window in that position If the window is not released on one of the dock handles it floats All windows can be docked to any of the display handles or left to float anywhere on the screen Each window has its own set of dock handles allowing child windows to be docked with...

Page 54: ...st accurate results that are ISO compliant Automated ISO Setup 4 1 2 The Automated ISO Setup method was introduced for users desiring guidance in setting up the point locations for an M2 run that conforms to the minimum ISO requirements This method does not require any inputs from the user as it performs an initial scan of the beam propagation path to determine the point locations needed to confor...

Page 55: ...ation has shown that making these measurements in the far field region works just as well if not better If the beam is highly astigmatic the four cuts method has been known to fail In this case the X and Y waist locations are far apart and it is difficult to find the 3 starting cut points that satisfy the initial conditions As part of the Configuration Wizard shown in section 4 2 1 the user must e...

Page 56: ...gths A standard M2 measurement should be performed on the actual or similar beam to obtain this information Four Cuts on Two Axes 4 1 3 2 BeamSquared always treats lasers as if they have two orthogonal axes Because of this the Four Cuts method is expanded further and computes results separately along the X and Y axes This figure shows how the two axis samples are taken In this example the beam has...

Page 57: ... Fill From Run fills the table with the Z locations from the last run Select the Remove Z Location icon on any data point that is not desired to remove it from the list Real Time M2 Mode 4 1 5 The Real Time M2 mode provides continual real time monitoring of a laser beam It may be used to monitor a laser while the laser cavity is under adjustment providing a fast M2 estimate to the technician durin...

Page 58: ...icon when it is green to start Real Time M2 Press the icon when it is red to stop If the tuning operation continues for a long period of time the camera baseline calibration may drift and cause errors in the results BeamSquared Operation 4 2 Configuration Wizard 4 2 1 The Configuration wizard walks the user through system settings to provide accurate results from an M2 run 1 Select Settings from t...

Page 59: ...e or the lens for manual mode To locate the waist relative to the laser enter the distance from the BeamSquared reference datum to the laser faceplate d The Automated BeamSquared system collects the Focal Length from the lens cassette RFID feature and automatically corrects the value based on the entered wavelength Enter the Focal Length of the lens used to create the artificial beam waist in mill...

Page 60: ...where between the focused beam waist and the lens Enter the Z distance of the first measurement location as measured from the lens to the image plane of the camera sensor ii Move the rail to either the B position or until the beam fills about 2 3 of the camera s imager on the opposite end of the rail to get the Z Stop value Enter the Z location that corresponds to the last measurement location of ...

Page 61: ...be a point beyond the waist where the beam width is smaller than at Z1 iii The Z3 should be a point selected beyond the waist and should be a value close to Z2 where the beam width of Z1 falls between the widths at Z2 and Z3 iv The remaining cuts are populated automatically by the software If these criteria are not met the wizard fails and an error appears terminating the run Should this occur ree...

Page 62: ...s additional settings You can set the Number of Runs in the field Multiple Runs gives the user statistical analysis of the enabled measurements Statistics is always set to Continuous Statistical results contain the following items Mean Standard Deviation Minimum Maximum Statistics are only computed for the M2 results items not for the individual frames Statistical results are computed based on the...

Page 63: ...ton at the bottom of the window If the window is closed before the run is complete or aborted reopen it through the Views panel Until the run has concluded other controls are unavailable The Finish Run button does not appear until a beam caustic is computed Frame Quality The software performs an image quality check and indicates if there are any recommended corrections A frame that has quality iss...

Page 64: ...e run a new Ultracal cycle must be performed before the frame can be accepted Click Redo Ultracal to initiate the process Ultracal is also used to compensate for small changes in the camera baseline due to changes in the camera temperature This is caused by the camera s natural warm up time or by ambient temperature changes As soon as a good frame is found live playback stops The user then has the...

Page 65: ...detected When configuring Start and Stop locations there are inaccessible locations at each end of the translation space The Start location must be greater than the minimum accessible location and the Stop must be less than the maximum Plotted Curve Fit 4 4 2 The X and Y axis results are reported and computed simultaneously Two data points for each location and two plotted fits to the data appear ...

Page 66: ...rovide feedback to the operator The 2D Beam Display window shows the energy distribution profile of the beam These are cross sections of the beam at various distances Z locations after the lens the Data Points in the image right The X and Y widths of the beam at each of these locations are plotted in the Caustic Beam Display window while the results are displayed in the Results window The five mai...

Page 67: ... focal length of the lens If it is not possible to obtain beam width measurements at the focal length of the focusing optic the software will use a Fitted Divergence feature Fitted Divergence calculates the divergence from the curve fit rather than the actual data point at the focal length Be sure to use converted focal length when measuring wavelengths other than the wavelength where the lens foc...

Page 68: ...ports all three values For the remainder of this discussion we will only refer to the M2 form The International Organization for Standards ISO subcommittee on electro optical systems has created a standard for test methods relating to the measurement of laser beam parameters BeamSquared employs algorithms that conform to the methods described in the ISO 11146 1 and 11146 3 2005 E procedures Copies...

Page 69: ...the descriptions that follow we use W to represent the full beam width while ISO uses dσx and dσy for the full beam widths and dσ for diameter and others use W or w to represent the beam width or radius Θ is used to describe the full angle divergence An f is used to indicate the focal length of the lens When a beam is transformed through a lens the input beam parameters are designated by a 1 and t...

Page 70: ...eam propagation parameters for a given laser system is difficult if not impossible Factors that limit the ability to characterize a laser include The laser waist is in a non accessible location such as inside the laser cavity The waist does not exist in real space but rather behind the laser cavity in virtual space The beam has a large W0 making it difficult to locate with great precision This cau...

Page 71: ... that transforms with a focusing lens The position of the focusing lens relative to the input beam s waist can alter the location of the waist formed after the lens sometimes dramatically ISO 11146 instructs that at least 11 samples are required to make an accurate M2 measurement with a minimum of 5 taken within ZR from the waist and 5 taken beyond 2ZR from the waist The figures below show how the...

Page 72: ... than satisfactory BeamSquared has included alternate beam width measurement techniques to compensate for this These methods degrade accuracy but may provide more correct results when extraneous noise is present in the beam wings The ISO procedure recognizes the problems with making direct second moment beam width measurements and allows for alternate measurement methods The knife edge method is d...

Page 73: ...ritical 2 Small Spot Size Conversely due to the pixel size a small beam causes an even greater challenge Experience has shown that measuring a beam less than 10 pixels wide in either the X or Y direction yields unsuitable results BeamSquared will not prevent you from making such measurements but the resulting accuracy will be degraded Camera Pixel Pitch Minimum Beam Width SP300 3 69 µm 36 9 µm SP9...

Page 74: ...limit of the camera Large Beam M2 1 The next image shows these same large beams sizes with an M2 2 Now none of the focused spot sizes of these examples are near the resolving limits of the camera Large Beam M2 2 The next set of images demonstrates the effect of the focused spot size for variations in wavelength Notice that shorter wavelengths focus smaller than longer wavelengths ...

Page 75: ...400mm Focal Length Lens M2 1 500mm Focal Length Lens M2 1 ...

Page 76: ...tandard warranty M2 Theory of Operation 5 5 BeamSquared measures beam parameters by combining an aberration free lens a detector translation system and the requirements described in the ISO procedure The beam passes through the lens to create an artificial waist or focus spot The propagation of the laser beam through a focus has a direct relationship to how the real unfocused beam propagates in sp...

Page 77: ...at effect laser beams mode content aperture induced diffraction and optical defects only mode content is suitable to the current M2 measurement methods The latter two types of defects depending on severity yield varying degrees of anomalous results using the present methods Because BeamSquared computes separate M2 results for both the X and Y axes the beam must exhibit either radial symmetry or bi...

Page 78: ...urements are obtained for the actual propagation of the laser 1 space and the beam formed by the focusing optic 2 space To obtain a more accurate measurement data points should be taken with smaller step sizes near the waist and larger step sizes in the far field One measurement should be performed at the focal length of the lens This provides the focal length divergence results The number of samp...

Page 79: ...on 4 repeated below using a non linear least squares technique 𝑊02 𝑧 2 𝑊02 2 𝛩2 2 𝑧 𝑍02 2 The results of the fit yield values for W02 Z02 and Θ2 in both the X and Y axes M2 K Factor and BPP 6 1 1 Equation 5 M2 and K Factors The M2 or K factor is computed from the values obtained from the curve fit as 𝑀2 1 𝐾 𝑊02𝛩2𝜋𝑛 4𝜆 Where 𝜆 The laser wavelength in a vacuum 𝑛 The index of refraction of the medium...

Page 80: ...t equivalent beam widths for beams that are predominantly TEM00 as well as for many other mixed mode combinations There are a few modes for which this method will not prove as accurate such as Top Hat shaped beams If laser mode content is not suitable for measurement using either of the previous methods use the Knife Edge Prog method and enter custom clip levels and a multiplier Suggested multipli...

Page 81: ...m waist location are included Waist Location Relative to Principal Plane 6 1 2 3 1 The first method applies when the Zlaser value is set to zero Per ISO the Waist Location results are computed from the first principal plane of the lens location H1 in in the figure below Equation 9 Waist Location when Zlaser 0 𝑍01 𝑓2 𝑍02 𝑓 𝑍𝑅2 2 𝑍02 𝑓 2 𝑓 Because the lens principle plane is not accessible in BeamSq...

Page 82: ...esults are positive when the waist is in front of the BeamSquared or in front of the laser and negative when not accessible either after the BeamSquared or behind the laser aperture In this computation no adjustment is made to correct for the small difference between the H1 and H2 principal planes Rayleigh Range 6 1 3 The Rayleigh range is the distance from the waist where a beam of a circular dia...

Page 83: ...cularity of the beam is depicted with the Asymmetry result This value compares the two waist widths and therefore only has significance if there is little or no Astigmatism Asymmetry values approaching 1 indicate that the beam appears circular in the waist region Values greater than 1 indicate Ellipticity or asymmetric behavior Equation 14 Asymmetry 𝐴𝑠𝑦 𝑡ℎ𝑒_𝑔𝑟𝑒𝑎𝑡𝑒𝑟_𝑜𝑓 𝑊01𝑋 𝑊01𝑌 𝑜𝑟 𝑊01𝑌 𝑊01𝑋 Focal ...

Page 84: ...ength values are defined as follows refer to image below Zlens the distance from the red BeamSquared case to the reference plane of the lens Zfixture the internal beam path length from the reference plane of the lens to the camera mount when the mirrors are in the A or minimum position green path Zcam the distance from the camera mount to the camera detector surface The sum of these three values e...

Page 85: ...factory and does not change unless the unit is damaged and repaired at the factory This value is always associated with a particular BeamSquared serial number and is automatically loaded on software startup or device connection Z Camera 6 1 6 3 The Zcam distance can vary depending on the physical characteristics of the camera BeamSquared is supplied with an adapter that supports both C mount and C...

Page 86: ...2 𝑀4 𝑍02 𝑓 1 𝑓 Where 𝑍01 The before lens waist location 𝑍02 The after lens waist location 𝑀4 The beam quality factor M2 squared 𝑍𝑅2 The after lens beam Rayleigh length The above equation can be used to aid in the determination of laser placement relative to the BeamSquared lens What follows are four example plots of after lens waist location 𝑍02 versus before lens waist location 𝑍01 2 Sun H Thin l...

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Page 88: ...SB 3 or USB 3 1 USB 2 cables do not provide satisfactory performance Did the installation complete successfully There should have been no error messages during installation If so retry the installation Only the BeamSquared camera connects Data Source panel on the Source ribbon looks like this Ensure AC power is connected Table calibration fails No table movement sound during initial calibration En...

Page 89: ...er focal length lens or adjust the position of the BeamSquared unit along the beam propagation path BeamSquared reports that the step spacing in Automated Mode may be too large Determination of the appropriate step size by BeamSquared is only a heuristic You may still be able to achieve an ISO defined 11 sample run Try an experimental run using your preferred settings If at least 11 samples are ta...

Page 90: ...led turn it off The measurement run does not include a sample taken at the effective focal length of the lens The Divergence result in the Results window displays as Fitted Divergence The Z position at the effective focal length is less than the first sample Z position Re configure your run parameters to start the run somewhere between the minimum table position and the effective focal length Erro...

Page 91: ...M server to provide an automation interface More recent technologies like NET provide more fully featured programming functionality Recent developments in remoting technologies allow nearly transparent interaction between machines on the same domain This allows the user to leverage more than one PC while using BeamSquared for analysis COM remote operation is more difficult to use and setup when co...

Page 92: ... reference is presented in a software industry standard html format which provides cross referenced access to all interfaces and functionality provided for automation application development The BeamSquared Automation API reference may be accessed via the following path Start All Programs Spiricon Documentation BeamSquared Automation Interface Complete class documentation is generated from annotat...

Page 93: ...ce from the lens are plotted and the hyperbolic curve fits are drawn Results are reported for the actual propagation of the laser 1 space and the fitted beam formed by the focusing optic 2 space If the data plot contains anomalous data points outliers the operator can selectively remove these data points from the analysis by double clicking them in the Caustic Beam Display In manual mode the user ...

Page 94: ...sed spot size is plotted against the input waist location for a variety of input beam sizes shown representing only M2 1 Focused spot sizes are always larger when M2 1 The next image depicts the focused spot sizes for larger input beam sizes also with M2 1 Notice that around 5mm the focused spot size falls below the 800μm dotted line which represents the resolution limit of the camera For these la...

Page 95: ...h an M2 2 Observe that now a 10mm beam is around the resolution limit of the camera The next set of images demonstrates the effect of the focused spot size for variations in wavelength Notice that shorter wavelengths focus smaller than longer wavelengths ...

Page 96: ...om the lens to the sensor inside the camera for each data point Optical Rail Setup 9 3 1 The figure below depicts the general features of the optical rail arrangement The rail must be parallel to the incoming laser beam the lens and camera must be at the same height on the rail and the camera must be able to slide along the rail A two mirror arrangement for aiming the beam along the rail is sugges...

Page 97: ...to a safe level Additional ND filters can also be added in front of the camera to further adjust beam brightness If camera or other configuration parameters need to be changed do so now or restore the required configuration This will not be necessary if the last configuration saved corresponds to the current setup The following steps describe how to setup the rail with the lens and the camera 1 Cl...

Page 98: ...thirds of the imager Note the Z position Round this value off to the nearest 10mm this is the Z Stop value Move the camera back to the Z Start position 9 Determine a Z Step value that seems reasonable for the range between the Z Start and Z Stop values Typically a value between 30mm 50mm or 1 10 the focal length of the lens is appropriate If the beam focuses quickly consider reducing the step size...

Page 99: ...the camera s dynamic range the beam profile displays saturated areas where the beam intensity on the camera is too high The color of the saturation depends on the selected color palette When using the OSI Rainbow these appear white The beam intensity must be decreased in order to obtain an accurate measurement This can be accomplished by adding attenuation or modifying the measurement setup Failur...

Page 100: ... software performs an image quality check and indicates if there are any recommended corrections A frame that has quality issues can still be accepted but doing so is discouraged The possible warnings are Misaligned The edge of the beam has reached at least one edge of the sensor Measurement accuracy could be degraded Accept frame or Abort Run adjust the setup and take a new measurement Selecting ...

Page 101: ...on If the beam has quality issues this icon turns yellow A frame cannot be accepted if live playback is running or if a new Ultracal is required When accepting the frame on the last data point of the run the Step by Step wizard automatically closes Live Playback Re enable live playback to view the beam in real time Single Frame Collect a single new frame from the camera After the setup completes e...

Page 102: ...ly these equations to achromatic lenses 𝑓 𝜆 𝑓𝑐𝑎𝑙 𝑛𝑐𝑎𝑙 1 𝑛𝜆 1 Where 𝑓𝑐𝑎𝑙 The measured focal length of the lens at the calibration wavelength 𝑓𝜆 The calculated focal length of the lens at the desired wavelength 𝑛𝑐𝑎𝑙 The index of refraction of the lens substrate at the calibration wavelength 𝑛𝜆 The index of refraction of the lens substrate at the desired wavelength λ Section A 2 provides index of ref...

Page 103: ... 46301 496 5 1 52165 1 46252 514 5 1 52049 1 46156 532 0 1 51947 1 46071 546 1 1 51872 1 46008 587 6 1 51680 1 45846 589 3 1 51673 1 45840 632 8 1 51509 1 45702 643 8 1 51472 1 45670 656 3 1 51432 1 45637 694 3 1 51322 1 45542 706 5 1 45515 786 0 1 51106 1 45356 820 5 1 51037 1 45298 830 0 1 51021 1 45282 852 1 1 50981 1 45247 904 0 1 50894 1 45170 1014 0 1 50731 1 45024 1060 0 1 50669 1064 0 1 44...

Page 104: ...ring or replacing Goods that Ophir determines do not conform to the foregoing warranty or ii refunding the sales price received by Ophir in respect of the non conforming Goods This remedy shall be the Purchaser s sole and exclusive remedy for any defect or nonconformity in the Goods This warranty extends only to the immediate purchaser from Ophir and does not extend expressly or impliedly to any o...

Page 105: ...application This table displays the cameras BeamSquared currently supports Select a model to view the camera specifications See Appendix D for additional information on select cameras Model Automated BeamSquared Manual Mode Section SP300 X X D 1 SP920 X X D 2 XEVA XC 130 X X D 3 Pyrocam IIIHR X N A Pyrocam IV X N A ...

Page 106: ...t set the trigger control to In Select Off when operating in CW mode GPI O Connector Description D 1 3 The camera has an 8 pin GPIO connector on the back of the case refer to the diagram below for wire color coding The connector is a Hirose HR25 8 pin connector with part number HR25 7TR 8SA The male connector is part number HR25 7TP 8P 72 For all non isolated GPO GPI pins the voltage swing is as f...

Page 107: ...ge A trigger pulse should be at least 5μs in duration To operate in external trigger mode you must set the trigger control to In Select Off when operating in CW mode GPI O Connector Description D 2 3 The camera is equipped with a 6 pin GPIO connector on the back of the case The connector is a Hirose HR10A 7R 6PB the mating connector is a Hirose HR10A 7P 6S 73 This section contains reference materi...

Page 108: ...y special NUC non uniformity correction files that must be downloaded to the camera These correction files are supplied by the manufacturer and are unique to each camera NUC files provide gain offset and bad pixel correction for specific operating settings such as exposure gain black level imager temperature etc BeamSquared provides controls to employ the necessary NUC file There are two 2 types o...

Page 109: ...tionPacks 10 Click on an xca file name that contains TrueNUC_HG and click Open 11 Click Live Playback on the Run ribbon 12 The camera should start displaying data frames with a well corrected image with a raised black level baseline 13 The preset cooling temperature is normally 17 C Wait for the readout temperature to stabilize at this setting 14 Attenuate the laser and adjust the Exposure time to...

Page 110: ...ification purposes only D 3 3 2 Camera Correction File To successfully use an InGaAs camera such as the XC 130 a camera correction file must be applied The file must match how the camera is setup for use When the Xeneth software is installed it copies the camera correction NUC files into a folder called C Program files Xeneth CalibrationPacks This folder contains 2 or more xca NUC files specific t...

Page 111: ...nges in temperature To ensure a stable image baseline the temperature should be set to a value below the room temperature Since 27 C is a nominal room temperature and an operating camera will warm somewhat above this all TrueNUC files force a temperature value of 17 C The camera has a cooler that can lower the imager temperature but relies on normal heating of the camera to raise it The readout fr...

Page 112: ...e right to make improvements to the product described in this user guide at any time and without prior notice While every precaution has been taken in the preparation of this guide the publisher and author assume no responsibility for errors omissions or any loss of data because of said errors or omissions Personal computer hardware and component manufacturers along with operating system providers...

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