## On this page # Example 22 - C# Last update: 09.03.2026 ```csharp using System; using ZOSAPI; namespace CSharpStandaloneApplication { class Program { static void Main(string[] args) { // Find the installed version of OpticStudio bool isInitialized = ZOSAPI_NetHelper.ZOSAPI_Initializer.Initialize(); // Note -- uncomment the following line to use a custom initialization path //bool isInitialized = ZOSAPI_NetHelper.ZOSAPI_Initializer.Initialize(@"C:\Program Files\OpticStudio\"); if (isInitialized) { LogInfo("Found OpticStudio at: " + ZOSAPI_NetHelper.ZOSAPI_Initializer.GetZemaxDirectory()); } else { HandleError("Failed to locate OpticStudio!"); return; } BeginStandaloneApplication(); } static void BeginStandaloneApplication() { // Create the initial connection class ZOSAPI_Connection TheConnection = new ZOSAPI_Connection(); // Attempt to create a Standalone connection IZOSAPI_Application TheApplication = TheConnection.CreateNewApplication(); if (TheApplication == null) { HandleError("An unknown connection error occurred!"); return; } // Check the connection status if (!TheApplication.IsValidLicenseForAPI) { HandleError("Failed to connect to OpticStudio: " + TheApplication.LicenseStatus); return; } if (TheApplication.Mode != ZOSAPI_Mode.Server) { HandleError("User plugin was started in the wrong mode: expected Server, found " + TheApplication.Mode.ToString()); return; } IOpticalSystem TheSystem = TheApplication.PrimarySystem; // creates new directory string strPath = System.IO.Path.Combine(TheApplication.SamplesDir, @"API\CS"); System.IO.Directory.CreateDirectory(strPath); // Set up primary optical system string sampleDir = TheApplication.SamplesDir; string testFile = System.IO.Path.Combine(sampleDir, "Sequential\\Objectives\\Double Gauss 28 degree field.zos"); TheSystem.LoadFile(testFile, false); //! [e22s01_cs] // Set up Batch Ray Trace ZOSAPI.Tools.RayTrace.IBatchRayTrace raytrace = TheSystem.Tools.OpenBatchRayTrace(); int nsur = TheSystem.LDE.NumberOfSurfaces; int max_rays = 30; ZOSAPI.Tools.RayTrace.IRayTraceNormUnpolData normUnPolData = raytrace.CreateNormUnpol((max_rays + 1) * (max_rays + 1), ZOSAPI.Tools.RayTrace.RaysType.Real, nsur); //! [e22s01_cs] //! [e22s02_cs] // Define batch ray trace constants double hx = 0.0; int max_wave = TheSystem.SystemData.Wavelengths.NumberOfWavelengths; int num_fields = TheSystem.SystemData.Fields.NumberOfFields; double[] hy_ary = new double[] { 0, 0.707, 1 }; //! [e22s02_cs] // Initialize x/y image plane arrays double[,,] x_ary = new double[num_fields, max_wave, (max_rays + 1) * (max_rays + 1)]; double[,,] y_ary = new double[num_fields, max_wave, (max_rays + 1) * (max_rays + 1)]; //! [e22s03_cs] // Determine maximum field in Y only double max_field = 0.0; for (int i = 1; i <= num_fields; i++) { if (TheSystem.SystemData.Fields.GetField(i).Y > max_field) { max_field = TheSystem.SystemData.Fields.GetField(i).Y; } } //! [e22s03_cs] Random rand = new Random(); System.Text.StringBuilder sbReport = new System.Text.StringBuilder(); sbReport.AppendLine("Field \t Wave \t x \t y"); for (int field = 1; field <= num_fields; field++) { for (int wave = 1; wave <= max_wave; wave++) { //! [e22s04_cs] // Adding Rays to Batch, varying normalised object height hy normUnPolData.ClearData(); int waveNumber = wave; for (int i = 1; i <= ((max_rays + 1) * (max_rays + 1)); i++) { double px, py; px = rand.NextDouble() * 2 - 1; py = rand.NextDouble() * 2 - 1; while ((Math.Pow(px, 2) + Math.Pow(py, 2)) > 1) { py = rand.NextDouble() * 2 - 1; } normUnPolData.AddRay(waveNumber, hx, hy_ary[field - 1], px, py, ZOSAPI.Tools.RayTrace.OPDMode.None); } //! [e22s04_cs] // Run Batch Ray Trace raytrace.RunAndWaitForCompletion(); //! [e22s05_cs] // Read batch raytrace and save results normUnPolData.StartReadingResults(); int rayNumber, ErrorCode, vignetteCode; double double_X, double_Y, double_Z, double_L, double_M, double_N, double_L2, double_M2, double_N2, OPD, Intensity; bool success; success = normUnPolData.ReadNextResult(out rayNumber, out ErrorCode, out vignetteCode, out double_X, out double_Y, out double_Z, out double_L, out double_M, out double_N, out double_L2, out double_M2, out double_N2, out OPD, out Intensity); while (success) { if ((ErrorCode == 0) && (vignetteCode == 0)) { x_ary[field - 1, wave - 1, rayNumber - 1] = double_X; y_ary[field - 1, wave - 1, rayNumber - 1] = double_Y; sbReport.AppendLine((field).ToString() + "\t" + (wave).ToString() + "\t" + double_X.ToString() + "\t" + double_Y.ToString()); } success = normUnPolData.ReadNextResult(out rayNumber, out ErrorCode, out vignetteCode, out double_X, out double_Y, out double_Z, out double_L, out double_M, out double_N, out double_L2, out double_M2, out double_N2, out OPD, out Intensity); } sbReport.AppendLine(""); //! [e22s05_cs] } } string resFile = System.IO.Path.Combine(sampleDir, "API\\CS\\e22_seq_spot_diagram.txt"); System.IO.File.WriteAllText(resFile, sbReport.ToString()); //! [e22s06_cs] // Spot Diagram Analysis Results ZOSAPI.Analysis.IA_ spot = TheSystem.Analyses.New_Analysis(ZOSAPI.Analysis.AnalysisIDM.StandardSpot); ZOSAPI.Analysis.Settings.Spot.IAS_Spot spot_setting = (ZOSAPI.Analysis.Settings.Spot.IAS_Spot)spot.GetSettings(); spot_setting.Field.SetFieldNumber(0); spot_setting.Wavelength.SetWavelengthNumber(0); spot_setting.ReferTo = ZOSAPI.Analysis.Settings.Spot.Reference.Centroid; //! [e22s06_cs] //! [e22s07_cs] // Extract RMS & Geo spot size for field points spot.ApplyAndWaitForCompletion(); ZOSAPI.Analysis.Data.IAR_ spot_results = spot.GetResults(); Console.WriteLine("RMS radius: {0:F3} {1:F3} {2:F3}", spot_results.SpotData.GetRMSSpotSizeFor(1, 1), spot_results.SpotData.GetRMSSpotSizeFor(2, 1), spot_results.SpotData.GetRMSSpotSizeFor(3, 1)); Console.WriteLine("GEO radius: {0:F3} {1:F3} {2:F3}", spot_results.SpotData.GetGeoSpotSizeFor(1, 1), spot_results.SpotData.GetGeoSpotSizeFor(2, 1), spot_results.SpotData.GetGeoSpotSizeFor(3, 1)); //! [e22s07_cs] Console.WriteLine("Press any key to continue..."); Console.ReadKey(); // Clean up FinishStandaloneApplication(TheApplication); } static void FinishStandaloneApplication(IZOSAPI_Application TheApplication) { // Note - TheApplication will close automatically when this application exits, so this isn't strictly necessary in most cases if (TheApplication != null) { TheApplication.CloseApplication(); } } static void LogInfo(string message) { // TODO - add custom logging Console.WriteLine(message); } static void HandleError(string errorMessage) { // TODO - add custom error handling throw new Exception(errorMessage); } } } ```