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Spot centroid (CENX/CENY) vs Huygens PSF centroid (CEHX/CEHY) - why are they different?
Hello,I am getting about 100% difference when calculating the centroid using the two methods. Why are they so different? I was expecting ~10% difference. Should they not be identical for a paraxial lens?Thank you!Anton
How to tilt & denceter a component without disturbing other components?
Hi all,I have a question regarding the tilt and decenter specific elements without changing other components in an optical system. For example, as the 1st picture shown below, we have many mirrors tilted certain degrees, now, I would like to tilt the M1 mirror only, but still make the rest mirrors stay at the same position (not tilt and dencenter at all), but definitely, their size may change due to the tilt of M1 mirror. However, when I tilt M1 mirror, the rest system also change as shown in the second picture, if anyone can help me out for this problem, I really appreciate!The corresponding Zemax file also attached below for your reference if you would like to modify it for me!Thank you!
How to model the FOV scanner system used for telescope?
Hi all,I have a very fundamental question about modelling FOV scanner used for telescope system. Below I attach a picture showing that the ray caustic from the Three Mirror Anastigmat (TMA) forming a very good image at the intermediate image plane. (I don’t show the plot of the TMA system). And we use M4, Flat Mirror (FM) and M5 to form a basic FOV scanner system to shrink the size of the sensor.For example, we can tip & tilt the flat mirror to make almost each filed point (on & off axis) hit at the center of sensor (the pink ray bundle in the picture) which means the green and red ray bundle almost concide with the pink ray bundle . I start with only on-axis field and optimize to achieve a diffraction-limited system. However, when I use multi-configuration function to add more off-axis fields, for example (0 , 0.02 deg), and try to tilt the flat mirror, the system works very bad for off-axis field, I am just curious if any one have some inputs or suggestions, that would be ver
"Convert to Project Directory" new feature: two issues
I’ve just tested the new "Convert to Project Directory" feature with a design file using scripted tolerancing.I noticed the browsing dialog box (which appears to let the user select the project folder) does not let you create a new folder by simply inserting a new name. The user is forced to right-clic and create a new folder manually, then select it. the new project directory which is created misses some essential files: .MF , .TOP , .tsc
Marginal Ray solve function
Hi,Following Zemax tutorial, I add Marginal Ray Solve for my paraxial lens? What does it mean in practice? Also, my spot diagram has changed.I am sorry if my questions sound very basic, but I a very new to Zemax. Could you also suggest some easy-to-understand materials that would helps in making a sense out of analysing graphs and diagrams produced by Zemax?
Bug in Layout, Layout 3D and Shaded Modeling
This has been a bug in Zemax for going on decades now. Say I have a lens with three lenses between object and image. I view it with Layout, Layout 3D and/or Shaded Model. It draws fine.I then insert a new surface right after the object. Invariably, the lens viewing routines do not recognize this surface and now begin plotting at surface 2. The new surface 1 is totally ignored. I have to go back to layout settings and update the surface range to see the new surface.Why? This is such a simple thing to ask of Zemax lens viewing routines, to always plot all surfaces in the LDE. Why does this continue to be a bug?
Can OpticStudio sequential mode be used to model long distance free-space Gaussian laser beam propagation?
Hello everyone,There are 3 tools in OpticStudio sequential mode to model Gaussian laser beam propagation, ray-based approach, Paraxial Gaussian Beam analysis, and Physical Optics Propagation. In the knowledgebase articles (https://www.zemax.com/blogs/free-tutorials/modeling-laser-beam-propagation-in-opticstudio), the beam has been analyzed through the optical system as it propagates to 100 mm. It also recommends to use Paraxial or Physical Optics Propagation tool when the propagation length is long and beam is collimated.Will it be right to use Paraxial or POP if the propagation length is some hundred meters between transmitter and detector (as is in the case of free space optics FSO links) or there any limit on distance?Thank you for the reply!
OpticStudio Tolerancing : step size of compensator.
Hi there, In OpticStudio, during tolerancing, is there a way to request for the compensator to take specific step sizes within the designated range. For example for the comp range from -0.26mm to +0.26 mm, can we designate it to take 0.0125mm steps?thanks in adv, Phil
Tolerancing the input beam when using POP
Hello!I’m working on a system in which I evaluate physical optics propagation (POP) for beams of several different sizes in the merit function. The way I change the beam size within POP is using a little macro I wrote (see snippet below). This code works well when I’m optimizing or playing with values in the LDE, but it does not yield consistent results when I run a tolerance analysis. I suspect this is because of how .cfg files are handled during tolerancing.Is there a better way to modify the POP parameters so that they are modified appropriately during tolerancing? path$ = $PATHNAME() + "\"lensFilename$ = $FILENAME()lengthFilename = SLEN(lensFilename$)shortenFilename$ = $LEFTSTRING(lensFilename$, lengthFilename-3)cfgFilename$ = path$ + shortenFilename$ + "CFG"w0_in = PVHX() # read in the HX parameter. "PV" is a mnenomic for "pass value"! change the beam waist of the light coming from the fiberMODIFYSETTINGS cfgFilename$, POP_PARAM1, w0_in # Waist X of beam definition tabMODIFYSETTI
Why my paraxial lens stopped focusing after adding scan mirror?
Hi,I am using paraxial lens as an objective to focus scanned light beam. Before I added mirror to the system, the paraxial lens was focusing, but after mirror was added, the light was defocused. I thought “quick focus” may help, but instead I got negative focus. What I am doing wrong? Regards,Marzanna
Tolerancing for fiber coupling
Dear Experts,I have an optical system (refractive telescope + some lenses) to couple a laser beam into a single-mode fiber. I currently want to tolerance my system, so that the coupling efficiency does not drop below a threshold.Currently, I use as a tolerancing criterion RMS Wavefront or RMS Spot Radius with a Paraxial Focus compensator. This works fine, but I have the feeling that those criteria don’t model the fiber coupling very well. Fiber coupling efficiency drops sharply if the focus spot moves from the center position, even if I compensate the shift with “Align Receiver to Chief Ray” feature in the Fiber Coupling tool.I have tried to use the Merit function with a FICL operator, but this makes tolerancing really slow and FICL does not allow “Align Receiver to Chief Ray” I.e. sometime a smaller (better) RMS Spot Radius has a worse fiber coupling efficiency.Maybe somebody has an idea, how to model fiber coupling more efficient to make the right decisions in the tolerancing process
NSC Surface to object
I’m trying to model an anamorphic lens in non-sequential mode. The lens is planar on the incident side, and aspherical on the output side, with different asphere equations for x and y coordinates. The ‘Aspheric Surface 2’ seems to offer what I need in terms of the ability to specify different conic coefficients for x and y, but I cannot figure out how to create a volume from this. The format used in sequential mode, where the surface is preceded by a standard surface where the material is specified doesn’t work.Presumably the solution will be the same for any of the surface geometries offered in NSC mode, but all the examples and knowledgebase articles I can find apply mirror coatings to these surfaces, so they are modelled as infinitely thin shells.Any help would be greatly appreciated.
how to get the beam size and divergence at different FW for as non Gaussian beam
Dear all, I noticed that zemax gives the beam size and divergence at 1/e^2 FW (full width) (13.5% FW) but, I would like to have it at 10%. Does anyone know whether there is a way in zemax to get the beam size and divergence at other FW. My beam is not Gaussian so, I cannot simply convert the 13.5%, the zemax output, to 10% using the intensity distribution. Thanks in advance,Maryam
sagittal and tangential MTF values are far different
Hi everyone,Do you have an idea on why the sagittal and tangential MTF values are far by this much as shown below?Some details about the System: Off-axis mirror set, curved mirrors involved.Red arrow: sagittalYellow arrow: tangentialLooking forward
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