Use this space to learn more about your software!
Wide Angle Lenses Tutorial
Hi, I’m getting started writing a video on Wide Angle Lenses for my YouTube Channel DesignOpticsFast. I have a couple of questions:For Zemax Support:I’m having trouble getting the ‘enhanced wide angle ray aiming’ to make any difference: What does it do? I’ve toggled all the (new) switches under Ray Aiming in System Explorer and I’ve not been able to see any changes at all, let alone improvements. Can you guys explain where and when this Feature Experiment is intended to be useful? Or offer some sample files that show what it can do?Also, I wanted to check that the Performance Test measures raytracing speed AFTER the ray-aiming, so it won’t be a useful guide to how well or badly the ray-aiming is going. Is that correct?For Zemax Community:I’m interested in problems that you have in designing wide angle lenses. I’m trying to write a How-To that gives a step-by-step guide to setting up a wide angle lens. One problem I have is that it works with 100% of the files I create, so I wonder if I
Magnification of lens groups in total optical system
I want to know about magnifications of each lens groups in entire optical system. Especially, I wonder whether there are optimization operands about magnifications of each lens groups (defined surface to surface like operands EFLX, EFLY), or how to calculate the each magnifications of lens groups in entire optical system. Sincerely
Understanding the Method behind Huygens PSF
Hello everyone, I'm interested in finding out more details on the Huygens PSF method. The OpticStudio Help claims that 'a grid of rays is launched through the optical system'. Here I would like to know, what algorithm is used for the actual propagation. How are the abberations of all optical components accounted for? Are they propagated as rays, by paraxial propagation or by actually using Huygens formula? It would be very helpful if anybody could clarify this detail. Thanks a lot in advance, best wishes
About importing and simulating a phase profile of a DOE lens
Sometimes we might have some phase profile from a DOE lens or metalens and want to simulate it in OpticStudio. In this case, we can simply use the sequential surface 'Grid Phase' to import and simulate the data. However, care should actually be taken in this case. In short, if the phase profile comes from FDTD, BPM, or similar calculation, the data should only be used with POP but not ray-tracing. Otherwise the calculated result can be incorrect. Note here we are mainly focusing on importing a phase profile for DOE lens or metalens. To understand more details, we can first look at the following two slides to understand how the diffraction ray-tracing is calculated. The first slide shows how a ray is diffracted by a grating. It's important to know ray-tracing through a DOE or grating is calculated based on the 'frequency' or 'period', but not anything about the real structure. In the second slide, it further explains that the phase profile under this meth
Ask an Engineer: How do I model my laser beam in OpticStudio?
Topic: Selecting a laser propagation method in OpticStudioLive solution reveal and Q&A: July 20th, 8am - 9am PDT (See the attachments for a calendar invite)Engineer: @Angel Morales - Senior Application Engineer at Ansys Zemax Ask an Engineer is LIVE again this month! Try out the challenge below to learn more modelling laser beams in OpticStudio, then come back on July 20th to discuss. Submit your solution or questions as a reply to this thread. Challenge opens: July 7thSubmit your file as a reply by: July 19th, EODLive event: July 20th 8am PST (the calendar invite is in the attachments)Challenge: OpticStudio supports several different approaches to model a laser input for your system. They include:Defining your geometric ray bundle with the correct aperture apodization and divergence angle Utilizing the Paraxial Gaussian Beam or Skew Gaussian Beam analysis to define and propagate your laser beam Generating and analyze your laser beam using the Physical Optics Propagation analysis
How the polychromatic RMS wavefront error is calculated?
The polychromatic RMS wavefront error is calculated based on the following equation: RMS polychromatic = sqrt(sum ((optical path difference for each ray of the pupil for each wavelength)^2 x weight of the ray)/ sum(weight of the ray)). This means that the polychromatic RMS wavefront error is calculated for all wavelengths at the same time and for all the pupil. For polychromatic results, the reference is the primary wavelength, so the wavefront error is calculated for each wavelength at the same time but with the reference set to the primary wavelength for each wavelength used. This means that for each wavelength, the rays are first propagated until the image plane, then the optical path length of each ray is recorded, then the rays are propagated back to the reference sphere defined by the chief ray at the primary wavelength, then path length of each ray is recorded again during this back-propagation, and finally the back-propagation path length is subtracted from&nb
How to parametrize a "Paraxial lens" ?
Can someone explain to me ... 1) What does the column OPD mode correspond to, when you create a 'Paraxial lens' (the column after 'Focal length') ? 2) Is a Paraxial lens aberration-free for any conjugation or magnification ? Should I not enter some magnification somewhere when I parametrize a Paraxial lens ? 3) I did the following test : create a Paraxial lens with focal length 100mm with object at infinite,aperture diameter 25mm, field 15°. Look at spot diagrams (looks great !), look at PSFs (look great !), look at FFT MFT : looks great on axis ... but why is NOT so great off axis ? Many thanks Yvan Sortais
Nonsequential Mode: Coherent Optics, Problem with Detector rectangle and NSDC Operand
Hello, I have a very simple nonsequential model: Source Point: power=10 W, coherence length=0, linear polarized: Jx=Jy=1, collimated light: cone angle=0 Detector rectangle: placed behind source, normal incidence, number of pixels=1, polarization=2 for measuring power of y-polarized light Then I have a merit function: NSDD for clearing the detector NSTR for making the rey trace NSDC for measuring nonsquential coherent data I was expecting to get Ey (y-component of the E-field vector), if I take Pix=0, Data=2 as parameters for NSDC. But I got 1,581 as result. From my understanding the result should be Sqrt(10)*cos(45°)=2,236. What's wrong here? If I take Pix=0, Data=3 as parameters for NSDC I get 2,5 as result. Data=3 should calculate the power. Because power is proportional to amplitude of E-Field vector and 1,581^2=2,5 this is consistent. But according to Malus Law I was expecting to get 10W * (cos(45°))^2 = 5W. I would be very happy if someone can help me clarifying this
Distortion and Vignetting
Hi all, What is the correct way to analyze distortion in a system?At the settings in “Field Curv/Dist” plot there is an option to tick/untick “Ignore Vignetting Factors”.In several cases I noticed that I achieved quite different results between the options and I wonder how to relate to it.Which of the options represents a more credible result?Also, are there different cases that require to use each option individually or there is some general consent?If different cases require different method, then why and what should be the guideline? Thanks,Ziv
New Optimization Methods
Hi Zemax Team, I was pleased to see the new optimization routines in 21.1, but I have not yet succeeded in getting a better result (either in MF value or speed) with them than with the DLS optimizer. For example, in a typical imaging system design, optimizing for best RMS spot, I have a design with a starting MF of 0.02 with 12 variables, all thicknesses and radii. The results I get are: DLS: 0.0011 in 1.7 secs DLSx 0.0035 in 3.6 secs PSD 0.0035 in 3.6 secs For reference, Orthogonal Descent (which I know is not intended for this kind of optimization) gave 0.0037 in 2.9 secs. Can you give us some color on what kind of optimization problems these new algorithms are intended for? - Mark
Which operand I can use to fix focal length while optimizing lens in non-sequential mode?
Hi, I am trying to optimize a lens in NSC. Given by our limitation, I need to keep the focal length while optimizing the thickness, radius and other properties. In sequential mode, EFFL could work. However, I cannot find the corresponding operand in NSC mode. Does anyone know how to do it? Many thanks!
Understanding the Ray Fan plot
HiI tried to understand the Ray Fan in OpticStudio and ran into this problem I have a paraxial lens imaging an on-axis object (zero height) with 10 mm semi-diameter pupil size and focal length of 50 mm. Image plane is shifted 5 mm away from the focus intentionally, so it is at 105 mm from the lens. The Ray Fan plot is like this Defocus term is the slope of this line and equals 0.05. Considering the defocus formula DF = focus shift x marginal ray height (10 mm) / focal length (50 mm) gives a 0.5 mm focus shift instead of 5 mm. I am not sure if I have problem with the definition of defocus term or with interpreting the Zemax data. Any idea?
Surface roughness analysis
Hi,I need to perform some basic surface roughness analysis and would like to have an approximate reference point. In my case the surface roughness needs to be expressed as Ra value, arithmetic mean of the profile height deviations. What are typical surface roughness values expressed as Ra for “cheaper” Illumination grade optics ?For example for this lenshttps://www.edmundoptics.de/p/125mm-h-x-25mm-l-x-25mm-fl-uncoated-cylinder-lens/22729/ Is possible to get Ra ≤ 0.025 um in a cost-effective machining processing without post polishing steps ?What is the simplest way to simulate surface roughness Ra (or RMS) quality in Zemax ? marko
Laser Diode Astigmatism
For modelling laser diodes via 'source diode' the value of astigmatism matters. Data sheet of laser diodes typically don't show this value. I tried to derive this value from far field beam divergence in the slow axis plane. Slow-axis divergence @1/e2 points is typically slightly bigger than the FWHM value. Using far field divergence equation one derives the beam waist and using the beam diameter-as-a-function-of-distance 'z' equation one can back calculate the 'z' necessary to get the beam diameter equal to the emitting chip length (not cavity length) e.g. 50µm.. I am not sure if this is correct. Any other suggestion/experience would be welcome. I was also never sure if the source diode inputs 'X-divergence' and 'Y-divergence' (in fact 0.85 x FWHM values) refer to full angle or half-angle. Thanks, Dusan
Measure focal length of a lens
I am using a Zemax model of an Edmund Optics lens in my design. The lens has a focal point of 10mm at 587.6nm, but my instrument will use a 650nm laser. Is there a tool in Zemax that calculates the focal length of a lens, with consideration of wavelength? Alternatively, I would appreciate guidance on how to calculate this by hand. The best I have been able to do so far is eyeball the location where the light converges and measure that distance (which appears so be about 12.3 mm).
Already have an account? Login
Enter your username or e-mail address. We'll send you an e-mail with instructions to reset your password.