FRESNEL Quick Guide

Starting FRESNEL

Once you loaded the program into your computer, as you do with other Windows programs, double click the FRESNEL icon in the Program Manager to start FRESNEL and display the FRESNEL Main Window. On the top of this window you have Main FRESNEL Toolbar.

Apart from buttons conventional for Windows programs the Toolbar contains several shortcut buttons that control FRESNEL operation.

Creating a New Scheme

To create a new scheme choose File | New Schemeor press .
Scheme Window for a new scheme you will assemble appears inside FRESNEL Main Window. New Scheme Window contains "Source" and Target" elements. By default the name of new scheme is "Untitled". Previous Scheme Window (if exists) will be closed. If you have made any changes you haven't saved, FRESNEL asks if you want to save the changes before closing.
Choosing Elements and selecting among them what you need assemble your scheme.

Each element of the scheme is a computer model of a real optical element or an operation affecting laser beam characteristics. It is represented visually as a box with appropriate pictogram.
It is important to understand some relations between real optical system and visual representation of its model in Scheme Window.

The order of elements in Scheme Window is the same as order of elements in an optical system.
Position and size of the element box inside Scheme Window are not associated with the physical location and size of a real element.

Parameters of each element including its distance from the previous element should be set in the elements dialog box that is evoked by double clicking the element box. List of parameters is varied according to the type of element.

Inserting Elements

To add new element to a scheme, define type of element to be added. The simplest way to define type of new element is the following:

Press Ins (shortcut of Add command in Edit menu). The Select Type of New Element dialog box appears.
Double-click the type of element you want to add. Cursor will change to indicate the type of element you are placing. Drag the mouse to the place where you want to insert the new element in Scheme Window.
Background of the element after which the new element will be added turns white. Click with mouse and new element will appear in the scheme.
If you want Cut or Copy an element of your scheme click it with your mouse. Then use shortcut button of the Main toolbar to cut the element or to copy it. You can Paste copied element. Just press and drag your mouse to the place where you want to paste the element. Background of the element after which the new element will be pasted turns white. Click with mouse and pasted element will appear in the scheme.
Source and Target can't be cut, copied or deleted.

Editing an element

To modify parameters of an element just double-click the element and the dialog box with element parameters appears. The options in this dialog box vary according to the type of element you are working with. Set up parameters you need and press OK.

Setting Target

FRESNEL runs your scheme until beam reaches the scheme output - Target element. Double click Target and adjust its distance from previous element. This will correspond to the output plane of your scheme. Changing Magnification of the beam after Target you can study the calculation result more carefully.
If there are many elements in the scheme, by changing location of the Target within elements chain you can select easily part of the scheme for running. Elements following the Target in your scheme are excluded from computations.

Saving Scheme

To save current scheme to a disk use the File | Save Scheme command or press the shortcut button . If the scheme has been newly created, then Save As dialog box appears.

Setting Source (Input beam)

Double click Source to select initial beam shape. The Select Beam Shape dialog box with list of available shape names will appear. Select shapes name you want and press OK.

Dialog box to define beam shape parameters will appear. The options in this dialog box vary according to the type of beam shape you selected (an example of the dialog box you can see is given in Section Diffraction). The dialog box is divided into parts that are general for all beam distributions: Grid and Beam Parameters. First one is to choose number of sampling points (discretization) and scale where the beam is defined. Others are to define wavelength, energy, temporal shape and beam geometry.
After you have set Beam parameters press OK and "In"-Beam Window will appear.

Previous: Foreword     Next: How to navigate in Beam Window