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The rigorous analysis of a sinusoidal grating by FMM is discussed.  The near
field as well as the diffraction efficiency is discussed. The parameter run
is used, to maximize the diffraction efficiency of the 1st order by the
height of the grating profile.

This module replicates a one- or two-dimensional, equidistantly sampled data array periodically. Therefor the user has to specify an  integer replication factor for both x- and y-direction.

This snippet defines a lens array on a hexagonal grid. Each lens is a conical interface. 

The module can be used to extract the information of a grating cells array (GCA) and convert it to a transmission function. This transmission function can be used for further investigations and additional export formats of the GCA diffuser.

This tutorial demonstrates how to input measured radiant intensities into VirtualLab‘s™ far field source.

This tutorial gives an introduction to the import wizard for data arrays. An overview about the possibilities of the import wizard is given.

The module is applied to a 2D harmonic field. The harmonic  field is covered by an array of cells with a user-defined size. The power of the harmonic field is computed for all cells and the values are shown as data array.

This module converts a harmonic field given in spectral domain to a Data Array in Cartesian angles

It is convenient to set the modulation of the angular distribution in the far field source by data that have been calculated from radiant intensity measurements. The "Databased Input" for this source is calculated by this module.

In this webinar we are going to inform you about parametric optimization of laser systems with LightTrans VirtualLab™ 4.10. The optimization is based on LightTrans field tracing concept and allows taking into account diffraction, interference, polarization and aberration effects. In addition optimization can be done with respect to typical laser optics merit functions, as for example, laser beam parameters, efficiencies and uniformity error.

In this webinar we are going to inform you about parametric optimization of laser systems with LightTrans VirtualLab™ 4.10. The optimization is based on LightTrans field tracing concept and allows taking into account diffraction, interference, polarization and aberration effects. In addition optimization can be done with respect to typical laser optics merit functions, as for example, laser beam parameters, efficiencies and uniformity error.

VirtualLab™ 5 introduces a variety of new features and improvements. The Lighting Toolbox enables the design and analysis of illumination systems for homogenization and shaping of LED light by micro structured components. In addition VirtualLab™ 5 simplifies the design of refractive beam shaping systems. The webinar will introduce the rigorous parametric optimization of gratings and will discuss it on the sample of the design of a subwavelength polarizer.

VirtualLab™ 5 introduces a variety of new features and improvements. The Lighting Toolbox enables the design and analysis of illumination systems for homogenization and shaping of LED light by micro structured components. In addition VirtualLab™ 5 simplifies the design of refractive beam shaping systems. The webinar will introduce the rigorous parametric optimization of gratings and will discuss it on the sample of the design of a subwavelength polarizer.

This application scenario demonstrates the design and analysis of an illumination system for the shaping of LED light into a cross light pattern. The shaping is done by a grating cells array.

This example demonstrates the setup of a beam shaper system by the refractive beam shaper session editor. The optical performance of the resulting system can be improved by the parametric optimization of VirtualLab™.

This application scenario demonstrates the parametric optimization of a sub-wavelength rectangular chromium grating used to polarize incident VIS light. For this purpose the modulation depth and the slit width of the grating are varied to find an optimal combination of maximal TE polarization and high polarization contrast (> 50) of transmitted light for wavelengths from 450 nm to 800 nm.

This application scenario demonstrates the parametric optimization of an aspherical focusing lens for coupling of a collimated laser beam in a single mode fiber. The goal is to optimize the radius, conical constant of the conical interfaces and distance between lens and fiber such that the fiber coupling efficiency is maximized. Simulation and optimization take into account diffraction, interference and aberration effects if necessary and allow wave-optical quality measurements.

This example demonstrates the rigorous simulation of a coated sinusoidal grating and it illustrates the effect of the coating on the summed efficiency of all reflected orders.

This application scenario demonstrates how an interferometer can be set up in VirtualLab.

This application scenario shows the optimization of a lens system by the parametric optimization document of \VLab . The goal is to optimize a system with two spherical lenses so that a laser beam is focused in the target plane. The spherical lenses are modeled as a sequence of four conical interfaces with conical constant zero.

The optimization and analysis of a pillar-type sub-wavelengths antireflection grating by rigorous Fourier Modal Method is demonstrated in this example. The optimization of the grating parameters is done by the parameter run of VirtualLab™.

This application scenario shows the simulation of a light source whose spectral composition is equal to that of the sun.

One can analyze a grating within the Grating Toolbox either with or without a homogeneous base block. This application scenario shows how resonance effects within this homogeneous region influence the transmission efficiencies of a sinusoidal grating.

This scenario shows how an LCD source consisting of a matrix of RGB pixels  can be generated in  VirtualLab™. The same approach can be used for any multi-color source based on pixels.

In this scenario we demonstrate the import of laser resonator systems from LASCAD into VirtualLab™. We show how these setups can be modified and analyzed in VirtualLab™. In particular the aperture at the right mirror is being modified and the influence on the radius, the M²-value of the beam and the discrimination of higher modes is shown.

This application scenario demonstrates how tolerancing can be done with the Parameter Run.

This scenario shows the simulation of a high NA beam shaping system. The systems contains a free form surface, described by a polynomial interface, for reshaping of a laser beam.

The simulation of a bifocal lens with a microstructure is demonstrated. The programmable interface of VirtualLab is used therefor.

Example for the homogenization of a LED by two lens arrays with rotational symmetric lenses. 

In this scenario we simulate and visualize the buildup of laser oscillation based on the Fox-Li numerical approach.

Example for the simulation of the light propagation through a non-paraxial aspherical lens and the simulation of vectorial effects in the focal region.

Surfaces in VirtualLab™ are usually smooth. In contrast, real surfaces are always rough to a certain degree. This application scenario explains how measured data of a real surface can be imported from an ASCII file and how the resulting scattering can be analyzed in VirtualLab™.

In this application scenario  we show how a resonator with a micro-structured mirror can be designed such that  the eigenmode has a pre-defined amplitude. In particular we design an eigenmode with a top-hat shape.

The simulation of a high NA refractive micro lens array will be demonstrated. The microlens array is simulated using the programmable interface.

The simulation of a sinusoidal grating with a rough random surface will be demonstrated. The simulation is done using the programmable grating of VirtualLab™.

Demonstrates the simulation of a spherical lens used for coupling of light into a single mode fiber and shows the optimization of the fiber position by the parameter run.

This scenario shows the simulation of a diffractive beam splitting element by the double interface component of VirtualLab™. The surface profile is defined by discrete height samples. For the simulation the sampled interface will be used.

In this scenario we show how parameter studies can be realized in VirtualLab™ in order to investigate the dependence of eigenmodes of resonators from system parameters. In particular we consider the variation of aperture sizes and the resulting variation of beam parameters as radius and M^2.

This scenario demonstrates  how eigenmodes and eigenvalues of laser resonators can be computed. Resonators with idealized components (mirrors, lenses) and real components with index modulated media are considered.

This application scenario for VirtualLab™ demonstrates how to rigorously calculate the field inside a grating with two examples: an isosceles triangular grating and a chromium slit.

The reflectivity of fiber Bragg gratings in dependency of the wavelength and the length of the fiber is analyzed in VirtualLab™.

Hybrid laser modes are locally polarized. Its generation is illustrated. Especially radial and azimuthal polarization is considered. The polarization view is used to investigate local polarization.

A coated slanted grating is generated with the Programmable Grating Component of VirtualLab™.

Shows the design of a diffractive optical element for diffuse deflection of light along the x-axis.

Example for the optimization of a diffractive optical element for diffuse illumination of a rectangular area (Top Hat)

Example for the design of a diffractive optical element for the generation of a general 2D diffuse intensity distribution.

Example for the design of a diffractive optical element for the generation of a general 2D diffuse intensity distribution. Valid for: Diffractive Optics Toolbox Basic.

The application scenario shows the design of a diffractive beam splitter for splitting of one laser beam into a regular array of 5x5 beams.

The application scenario shows the design of a diffractive beam splitter for splitting of one laser beam into a regular array of 5x5 beams.

This application scenario demonstrates the design of a diffractive beam splitting element for the generation of a 2D spot array. The spot array is defined by a bitmap file.

This application scenario demonstrates the design of a diffractive beam splitting element for the generation of a 2D spot array. The spot array is defined by a bitmap file.

The application scenario shows how to perform a rigorous analysis of a diffractive 1:6 beam splitter optimized by the diffractive optics toolbox.

Shows the simulation of a homogenization system for an excimer laser beam using a diffractive diffuser. The diffuser is optimized to generate a circular top hat.

Shows the simulation of a homogenization system for an excimer laser beam using a diffractive diffuser. The diffuser is optimized to generate a circular top hat.

Illumination of Rectangular Area (Top Hat) with High Homogeneity by Diffractive Beam Shaper

Shows the simulation of the light propagation through a non-paraxial spherical lens and the simulation of the quality of a laser beam in the focal plane.

Shows the simulation of the light propagation through a non-paraxial spherical lens and the simulation of the quality of a laser beam in the focal plane.

Demonstrates the import of lens data from Zemax and the simulation of light propagation through lens system including the calculation of laser beam parameters in focal plane.

Demonstrates the import of lens data from Zemax and the simulation of light propagation through lens system including the calculation of laser beam parameters in focal plane.

This application scenario shows the simulation of a non-paraxial beam shaping system.  The diffractive beam shaping element is expressed by a  quantized 4-level phase transmission.

This application scenario shows the simulation of a non-paraxial beam shaping system.  The diffractive beam shaping element is expressed by a  quantized 4-level phase transmission.

Demonstrates the import of a user defined phase plate from ASCII or bitmap data and shows the simulation of the diffraction at this plate. Valid for: Starter Toolbox Basic; Diffractive Optics Toolbox Basic

Illustration of transforming linearly into circularly or any kind of elliptically polarized light. The use of Jones matrices and the Polarization View is described.

Illustration of transforming linearly into circularly or any kind of elliptically polarized light. The use of Jones matrices and the Polarization View is described.

A 2f-setup is used to investigate far-field diffraction at a rectangular and circular apertures, which is modeled by an ideal aperture transmission function.

A 2f-setup is used to investigate far-field diffraction at a rectangular and circular apertures, which is modeled by an ideal aperture transmission function.

Near field diffraction of a Gaussian beam at an aperture, which is modeled by an ideal aperture transmission function, is investigated.  To this end the automatic propagation operator is used.  Continued in RSI.002c.

Near field diffraction of a Gaussian beam at an aperture, which is modeled by an ideal aperture transmission function, is investigated.  To this end the automatic propagation operator is used.  Continued in RSI.002c.

Near field diffraction of a Gaussian beam at an aperture, which is modeled by an ideal aperture transmission function, is investigated.  To this end the Parameter Run feature of VirtualLab is used to illustrate the change of the field dependent of the distance.

Near field diffraction of a Gaussian beam at an aperture, which is modeled by an ideal aperture transmission function, is investigated.  To this end the Parameter Run feature of VirtualLab is used to illustrate the change of the field dependent of the distance.

The resolution limit of an imaging system with an ideal lens is investigated. To this end we use an ideal grating object and consider its image for different periods.  Abbes resolution limit  is illustrated. The effect of the wavelength on the resolution is also demonstrated. 

The resolution limit of an imaging system with an ideal lens is investigated. To this end we use an ideal grating object and consider its image for different periods.  Abbes resolution limit  is illustrated. The effect of the wavelength on the resolution is also demonstrated. 

This tutorial demonstrates how to input measured radiant intensities into VirtualLab‘s™ far field source.

This tutorial gives an introduction to the import wizard for data arrays. An overview about the possibilities of the import wizard is given.

This tutorial gives an introduction to the concepts and the usage of the Lighting Toolbox. Analysis and Design of Grating Cells Arrays are demonstrated.

This tutorial gives an introduction to  the usage of the parametric optimization in  VirtualLab™. As an example, we consider the search of the focus of a spherical lens. 

This tutorial shows how databased interfaces are handled within VirtualLab. Two different kinds of interfaces are discussed, the sampled interface, which can be used for equidistant data, and the transition point list interface, which allows the user the description of an interface with 1D-non-equidistant data. The databased interfaces can be used for the investigation of measured height data.

This tutorial demonstrates how a Essential Macleod coating can be applied to the Single Interface component of VirtualLab™. 

This tutorial shows how surface profiles of optical interfaces can be manipulated in VirtualLab™. Definition areas (apertures), scaling, pixelation, quantization and periodization are being discussed.

This tutorial explains the usage of the structure design in VirtualLab™. Also the handling for import and export of fabrication data is shown.

This tutorial gives an introduction to the usage of the Raytracing Analyzer. This analyzer visualizes rays within components and the principles of the Geometrical Optics operator. 

Ultrashort pulse modeling with VirtualLab™ allows the investigation of fs pulses in focal regions. The tutorial explains the techniques to do that along an example with a high NA focusing lens.

VirtualLab™ enables modeling the propagation of ultrashort pulses through optical systems. This tutorial introduces you to basic techniques.

This tutorial explains the usage of 3D gratings in VirtualLab™.

This tutorial gives an introduction to the Laser Resonator Toolbox. It shows how the session editor is used to set up a resonator. Further the computation of eigenmodes is discussed. Finally it is show how the parameter run can be used to investigate the dependence of the eigenmode on parameters as the sizes of apertures.

This tutorial gives an introduction on how to use programmable light sources and programmable transmissions in a Light Path Diagram.

The rigorous analysis of a sinusoidal grating by FMM is discussed.  The near
field as well as the diffraction efficiency is discussed. The parameter run
is used, to maximize the diffraction efficiency of the 1st order by the
height of the grating profile.

Illumination of Rectangular Area (Top Hat) with High Homogeneity by Diffractive Beam Shaper

This tutorial gives a short introduction on how to setup and simulate a simple Light Path Diagram.

This tutorial gives a basic example on how to build up and modify a Light Path Diagram.

This tutorial gives a short introduction on how to use the Parameter Run
together with the Light Path Diagram in VirtualLab™. The Parameter Run
is used to vary parameters of an optical system automatically.

This tutorial gives a short introduction on how to setup the propagation in a Light Path Diagram.

This tutorial gives a short introduction on how to use detectors in a Light Path Diagram.

This tutorial gives a short introduction on how to setup materials and media
in a Light Path Diagram that is used in VirtualLab™ to describe optical
systems.

This tutorial gives a short introduction on how to use light sources in a Light Path Diagram.

This tutorial gives a short introduction on how to use light sources in a Light Path Diagram.

This tutorial gives a short introduction on how to setup materials and media
in a Light Path Diagram that is used in VirtualLab™ to describe optical
systems.

This tutorial gives a short introduction on how to use detectors in a Light Path Diagram.

This tutorial gives a short introduction on how to setup the propagation in a Light Path Diagram.

This tutorial gives a short introduction on how to use the Parameter Run
together with the Light Path Diagram in VirtualLab™. The Parameter Run
is used to vary parameters of an optical system automatically.

This tutorial gives a basic example on how to build up and modify a Light Path Diagram.

This tutorial gives a short introduction on how to setup and simulate a simple Light Path Diagram.

This tutorial gives an introduction on how to use programmable light sources and programmable transmissions in a Light Path Diagram.

This tutorial gives an introduction to the Laser Resonator Toolbox. It shows how the session editor is used to set up a resonator. Further the computation of eigenmodes is discussed. Finally it is show how the parameter run can be used to investigate the dependence of the eigenmode on parameters as the sizes of apertures.

This module replicates a one- or two-dimensional, equidistantly sampled data array periodically. Therefor the user has to specify an  integer replication factor for both x- and y-direction.

This snippet defines a lens array on a hexagonal grid. Each lens is a conical interface. 

The module can be used to extract the information of a grating cells array (GCA) and convert it to a transmission function. This transmission function can be used for further investigations and additional export formats of the GCA diffuser.

The module is applied to a 2D harmonic field. The harmonic  field is covered by an array of cells with a user-defined size. The power of the harmonic field is computed for all cells and the values are shown as data array.

This module converts a harmonic field given in spectral domain to a Data Array in Cartesian angles

It is convenient to set the modulation of the angular distribution in the far field source by data that have been calculated from radiant intensity measurements. The "Databased Input" for this source is calculated by this module.

fast fourier transform, execution time, computing time, design, module, IFTA, FFT, MOD.008, Module_008

The programmable mode planar source of VirtualLab allows the definition of customized modes being used in the planar source model. This snippet implements elementary modes resulting in a  cos^n-type radiant intensity  for the simulation of LEDs and other high NA sources including Lambertian sources with VirtualLab.

This snippet for the parameter run allows to vary two parameters equidistantly at the same time. All combinations of the two parameters are simulated.

This module can be used to export one physical quantity (e.g. amplitude, phase, …) of  each member of a selected harmonic fields set to a set of ASCII files. The user can specify the location to export to, as well as the physical quantity he likes to export. The exported ASCII files can be used for further investigation in other mathematical tools like MATLAB.

This snippet defines a surface profile of a truncated pyramid.

This snippet defines a surface profile of a truncated cone.

This snippet can be used to create a rectangular grating interface, which has round edges. This type of interface can be used to investigate some tolerance analyzes of the fabrication process.

The snippet defines a chirped gaussian pulse in time domain. This snippet can be loaded into the Programmable Pulse Spectrum generator which creates a complex spectrum over wavelength. For further investigations this spectrum can be used as spectrum of a light source in your optical system.

This snippet defines a toroidal interface.

This module shows intermediate results of the automatic propagation operator including the estimated numerical effort and estimates for the error of the individual free space operators. The propagation distance can be varied and the diagrams are shown for the automatic, spectrum of plane wave (SPW), Fresnel, far field and geometrical optics operator. 

This snippet defines a parameter run where an arbitrary number of parameters is varied randomly. It can be used for tolerancing.

This snippet defines a microlens array on a rectangular grid. Each microlens is a conical interface. 

The programmable interface of the optical interface component  of VirtualLab  enables the definition of customized freeform interfaces. This snippet allows modeling of anamorphic interfaces with VirtualLab™.

This module measures the profile width of a harmonic field, transmission, or signal field for a certain threshold (relative to maximum intensity). It is a generalized detector for measuring the full width at half maximum (FWHM).

This module generates a diagram with the spectrum of a Harmonic Fields Set at a certain (physical) position.

This snippet defines a cylindrical lens array function for a given rotation angle, period and focal length.

The module supports the user in setting up the parameters for the design algorithm and results in a  standard transmission design document that is used to perform the beam shaping.

 This snippet defines a double slit function for given width and distance of the slits.

This snippet defines a double pinhole function for given radius and distance of the pinholes.

This snippet defines a cylindrical lens function for a given rotation angle and focal length.

This snippet defines an axicon function for a given angle.

Current version of the VirtualLab™ Manual in PDF format. A PDF Reader (e.g. Acrobat Reader) is needed. (January 2012)

The propagation of harmonic fields through arbitrary optical
components is the fundamental task in optical modeling. Unified
optical modeling by field tracing uses different techniques for
different components in order to ensure the best compromise between
simulation effort and accuracy. This approach can be extended to
non-harmonic fields. With a set of harmonic fields modeling partial
coherence of stationary sources is enabled. The same approach can be
applied to model the propagation of fully coherent ultrashort pulses
through optical systems, which may include for instance lenses,
gratings and micro-optical components. For that we can rely on field
tracing with its numerous sophisticated propagation techniques for a
single harmonic field. Methods to reduce frequency domain sampling
are presented. They allow a convenient pulse modeling in practice.
Several examples are presented using ultrashort pulse modeling with
VirtualLab™.

Recently the importance of numerical simulations for the design of laser resonators has grown considerably. This applies in particular if the alignment
of components within the resonator is crucial for its stability. In such cases
a tolerance analysis is required that can be done most effciently using numerical simulation tools. In this paper, we introduce a computer model for
resonators based on components and their combination using absolute or
relative positioning.  We show that this approach is the basis for tolerancing and sensitivity analysis. Further we discuss the concepts of field tracing
and unified optical modeling that allow the coupling of several propagation
methods within one modeling task. For laser resonators this involves in particular free space propagation methods as the Fresnel integral, geometrical
optics and split step beam propagation methods.  The primary goal is to
provide a fully vectorial simulation as accurate as required and as fast as
possible. This approach covers in particular general eigenmode models and
general geometries including micro-structured surfaces that can be used for
additional beam control as it is shown in the examples.

In this webinar we are going to inform you about parametric optimization of laser systems with LightTrans VirtualLab™ 4.10. The optimization is based on LightTrans field tracing concept and allows taking into account diffraction, interference, polarization and aberration effects. In addition optimization can be done with respect to typical laser optics merit functions, as for example, laser beam parameters, efficiencies and uniformity error.

In this webinar we are going to inform you about parametric optimization of laser systems with LightTrans VirtualLab™ 4.10. The optimization is based on LightTrans field tracing concept and allows taking into account diffraction, interference, polarization and aberration effects. In addition optimization can be done with respect to typical laser optics merit functions, as for example, laser beam parameters, efficiencies and uniformity error.

Slides of a talk given at a workshop of Bayern Photonics in March 2011.

In this webinar we will inform you about innovations in the field of the rigorous electromagnetic analysis of general 2D and 3D gratings with the Grating Toolbox of VirtualLab™.

In this webinar we will inform you about innovations in the field of the rigorous electromagnetic analysis of general 2D and 3D gratings with the Grating Toolbox of VirtualLab™.

In this talk we present the concept of Unified Optical Modeling that allows to combine different simulation techniques within a single modeling task. In particular we focus on the combination of Finite Element Methods (FEM) with classical  propagation techniques including free space and geometrical optics propagation. We show that using locally adapted simulations techniques can speed up calculations considerably or can make them feasible at all. The described methods are especially useful in biological applications that are  characterized by different length scales, e.g. if the scattered field of cell structures is to be analyzed in the far field or behind a lens.

Slides of a talk given at the annual DGaO (German Society for Applied Optics) meeting in June 2009.

Slides of a talk given at the annual DGaO (German Society for Applied Optics) meeting in June 2009.

Unified optical modeling includes the analysis of color and coherence effects. The talk briefly discusses the principles of unified optical modeling and ist application for color and cohgernece modeling. VirtualLab, which is based on unified optical modeling,  is used to demonstrate the concepts.

Diffractive optical elements are often used in laser beam shaping systems. It is known that they are sensitive to the variation of wavelength. During the last years new design approaches of diffractive optical elements were suggested using the different dispersion characteristics of glasses. This allows the reduction of chromatic effects. Nevertheless the authors show that especially the angular dispersion can’t be removed.  The authors extend the known design methods for the optimization of refractive beam shaping elements. Again different glasses must be used to achieve an achromatization within a limited wavelength range. It is shown that this allow also the reduction of angular dispersion. The desig approach is demonstrated for the example of reshaping a Gaussian intensity distribution into a circular Top Hat.

Laser resonators consist in general of a series of single components including mirrors, lenses and homogeneous or index-modulated and active media. The goal of the simulation is to compute the eigenmodes of the resonator by an iterative procedure that requires propagating the light along the resonator in each iteration step. For that purpose several propagation techniques are available, for example, spectrum of plane waves and Fresnel integral, beam propagation methods (BPM) and ABCD Matrices with different approximation properties. It is shown that the simulation of resonators can be optimized with respect to accuracy and efficiency by adapting the propagation method locally to  the individual resonator components.

The use of CGHs for the generation of three dimensional signals and its holographic exposure is an already known idea. But in the past the state of PC technique limited the bandwidth product very strongly. Because of the technical development of 64-bit operating systems it becomey possible to make simulations with data fields which are bigger than 4GB. The new 64bit VirtualLab™ Advanced enables the calculation of high resolution signals, in which parallax and shadowing 3D effects are included. The calculated signals have a resolution of 50.000 by 50.000 sampling points and more. The result of the design is a binary CGH with a diffraction efficiency of about 10%. The 3D signal is copied into a photo polymer which results in a volume hologram with high diffraction efficiency.

This technical note gives an introduction to  the usage of the parametric optimization in  VirtualLab™. It describes the algorithmic background, especially how the target function is defined and how constraints are being handled.

This technical note describes the algorithm that is used for the generation of transition points as they are required by the Fourier Modal Method (FMM). The FMM is applied in VirtualLab™ for the rigorous analysis of gratings.

This technical note describes the update procedure that is necessary to update the dongle of VirtualLab™.

This technical note describes how VirtualLab™ can be customized with modules and snippets and describes the used syntax. It includes the VirtualLab™ Programming Reference.

This technical note describes how VirtualLab™ can import light field data and hence, at the same time,  how light field data have to be exported  by third party software such that VirtualLab™ can import these data.

This document describes the definition and use of positions in Light Path Diagrams

This document describes the interpretation of imported bitmaps as polychromatic light.

This document describes the correct display of light on a monitor.

This document contains the complete Release Notes of VirtualLab™.

This tutorial describes the update procedure that is necessary for the update of VirtualLab™ 3.x to VirtualLab™ 4.0.