diff --git a/Common/processfields.cpp b/Common/processfields.cpp
index bb295d3..765e51d 100644
--- a/Common/processfields.cpp
+++ b/Common/processfields.cpp
@@ -235,166 +235,6 @@ void ProcessFields::CalcMeshPos()
 	}
 }
 
-void ProcessFields::WriteVTKHeader(ofstream &file, double const* const* discLines, unsigned int const* numLines, unsigned int precision, string header_info, MeshType meshT, double discLines_scaling)
-{
-	if (meshT==CARTESIAN_MESH)
-		WriteVTKCartesianGridHeader(file, discLines, numLines, precision, header_info, discLines_scaling);
-	else if (meshT==CYLINDRICAL_MESH)
-		WriteVTKCylindricalGridHeader(file, discLines, numLines, precision, header_info, discLines_scaling);
-	else
-		cerr << "ProcessFields::WriteVTKHeader: Warning: unknown mesh type, skipping header -> file will be invalid..." << endl;
-}
-
-void ProcessFields::WriteVTKCartesianGridHeader(ofstream &file, double const* const* discLines, unsigned int const* numLines, unsigned int precision, string header_info, double discLines_scaling)
-{
-	file << "# vtk DataFile Version 2.0" << endl;
-	file << "Rectilinear Grid openEMS_ProcessFields";
-	if (!header_info.empty())
-		file << " " << header_info;
-	file << endl;
-	file << "ASCII" << endl;
-	file << "DATASET RECTILINEAR_GRID " << endl;
-	file << "DIMENSIONS " << numLines[0] << " " << numLines[1] << " " << numLines[2] << endl;
-	file << "X_COORDINATES " << numLines[0] << " " << __VTK_DATA_TYPE__ << endl;
-	for (unsigned int i=0; i<numLines[0]; ++i)
-		file << setprecision(precision) << discLines[0][i] * discLines_scaling << " ";
-	file << endl;
-	file << "Y_COORDINATES " << numLines[1] << " " << __VTK_DATA_TYPE__ << endl;
-	for (unsigned int i=0; i<numLines[1]; ++i)
-		file << setprecision(precision) << discLines[1][i] * discLines_scaling << " ";
-	file << endl;
-	file << "Z_COORDINATES " << numLines[2] << " " << __VTK_DATA_TYPE__ << endl;
-	for (unsigned int i=0; i<numLines[2]; ++i)
-		file << setprecision(precision) << discLines[2][i] * discLines_scaling << " ";
-	file << endl << endl;
-	file << "POINT_DATA " << numLines[0]*numLines[1]*numLines[2] << endl;
-}
-
-void ProcessFields::WriteVTKCylindricalGridHeader(ofstream &file, double const* const* discLines, unsigned int const* numLines, unsigned int precision, string header_info, double discLines_scaling)
-{
-	file << "# vtk DataFile Version 3.0" << endl;
-	file << "Structured Grid from openEMS_ProcessFields";
-	if (!header_info.empty())
-		file << " " << header_info;
-	file << endl;
-	file << "ASCII" << endl;
-	file << "DATASET STRUCTURED_GRID " << endl;
-	file << "DIMENSIONS " << numLines[0] << " " << numLines[1] << " " << numLines[2] << endl;
-	file << "POINTS " << numLines[0]*numLines[1]*numLines[2] << " " << __VTK_DATA_TYPE__ << endl;
-	for (unsigned int k=0; k<numLines[2]; ++k)
-		for (unsigned int j=0; j<numLines[1]; ++j)
-			for (unsigned int i=0; i<numLines[0]; ++i)
-			{
-				file << setprecision(precision) << discLines[0][i] * cos(discLines[1][j]) * discLines_scaling << " "
-				<< discLines[0][i] * sin(discLines[1][j]) * discLines_scaling << " "
-				<< discLines[2][k] * discLines_scaling << endl;
-			}
-	file << endl;
-	file << endl << endl;
-	file << "POINT_DATA " << numLines[0]*numLines[1]*numLines[2] << endl;
-}
-
-
-void ProcessFields::WriteVTKVectorArray(ofstream &file, string name, FDTD_FLOAT const* const* const* const* array, double const* const* discLines, unsigned int const* numLines, unsigned int precision, MeshType meshT)
-{
-	file << "VECTORS " << name << " " << __VTK_DATA_TYPE__ << endl;
-
-	if (g_settings.NativeFieldDumps())
-		meshT = CARTESIAN_MESH; //dump field components as they are...
-
-	unsigned int pos[3];
-	for (pos[2]=0; pos[2]<numLines[2]; ++pos[2])
-	{
-		for (pos[1]=0; pos[1]<numLines[1]; ++pos[1])
-		{
-			double cos_a = cos(discLines[1][pos[1]]); //needed only for CYLINDRICAL_MESH
-			double sin_a = sin(discLines[1][pos[1]]); //needed only for CYLINDRICAL_MESH
-			for (pos[0]=0; pos[0]<numLines[0]; ++pos[0])
-			{
-				switch (meshT)
-				{
-				case CARTESIAN_MESH:
-					UNUSED(discLines); //disclines not needed for the original cartesian mesh
-					//in x
-					file << setprecision(precision) << array[0][pos[0]][pos[1]][pos[2]] << " ";
-					//in y
-					file << setprecision(precision) << array[1][pos[0]][pos[1]][pos[2]] << " ";
-					//in z
-					file << setprecision(precision) << array[2][pos[0]][pos[1]][pos[2]] << endl;
-					break;
-				case CYLINDRICAL_MESH:
-					//in x : F_x = F_r * cos(a) - F_a * sin(a);
-					file << setprecision(precision) << array[0][pos[0]][pos[1]][pos[2]] * cos_a - array[1][pos[0]][pos[1]][pos[2]] * sin_a << " ";
-					//in y : F_y = F_r * sin(a) + F_a * cos(a);
-					file << setprecision(precision) << array[0][pos[0]][pos[1]][pos[2]] * sin_a + array[1][pos[0]][pos[1]][pos[2]] * cos_a << " ";
-					//in z
-					file << setprecision(precision) << array[2][pos[0]][pos[1]][pos[2]] << endl;
-					break;
-				}
-			}
-		}
-	}
-}
-
-
-bool ProcessFields::DumpVectorArray2VTK(ofstream &file, string name, FDTD_FLOAT const* const* const* const* array, double const* const* discLines, unsigned int const* numLines, unsigned int precision, string header_info, MeshType meshT, double discLines_scaling)
-{
-	WriteVTKHeader(file, discLines, numLines, precision, header_info, meshT, discLines_scaling);
-	WriteVTKVectorArray(file, name, array, discLines, numLines, precision, meshT);
-	return true;
-}
-
-bool ProcessFields::DumpMultiVectorArray2VTK(ofstream &file, string names[], FDTD_FLOAT const* const* const* const* const* array, unsigned int numFields, double const* const* discLines, unsigned int const* numLines, unsigned int precision, string header_info, MeshType meshT, double discLines_scaling)
-{
-	WriteVTKHeader(file, discLines, numLines, precision, header_info, meshT, discLines_scaling);
-	for (unsigned int n=0; n<numFields; ++n)
-	{
-		WriteVTKVectorArray(file, names[n], array[n], discLines, numLines, precision, meshT);
-		file << endl;
-	}
-	return true;
-}
-
-void ProcessFields::WriteVTKScalarArray(ofstream &file, string name, FDTD_FLOAT const* const* const* array, unsigned int const* numLines, unsigned int precision)
-{
-	file << "SCALARS " << name << " " << __VTK_DATA_TYPE__ << 1 << endl;
-	file << "LOOKUP_TABLE default" << endl;
-	unsigned int pos[3];
-	int count=0;
-	for (pos[2]=0; pos[2]<numLines[2]; ++pos[2])
-	{
-		for (pos[1]=0; pos[1]<numLines[1]; ++pos[1])
-		{
-			for (pos[0]=0; pos[0]<numLines[0]; ++pos[0])
-			{
-				file << setprecision(precision) << array[pos[0]][pos[1]][pos[2]] << " ";
-				++count;
-				if (count%10==0)
-					file << endl;
-			}
-		}
-	}
-}
-
-bool ProcessFields::DumpScalarArray2VTK(ofstream &file, string name, FDTD_FLOAT const* const* const* array, double const* const* discLines, unsigned int const* numLines, unsigned int precision, string header_info, MeshType meshT, double discLines_scaling)
-{
-	WriteVTKHeader(file, discLines, numLines, precision, header_info, meshT, discLines_scaling);
-	WriteVTKScalarArray(file, name, array, numLines, precision);
-	return true;
-}
-
-bool ProcessFields::DumpMultiScalarArray2VTK(ofstream &file, string names[], FDTD_FLOAT const* const* const* const* array, unsigned int numFields, double const* const* discLines, unsigned int const* numLines, unsigned int precision, string header_info, MeshType meshT, double discLines_scaling)
-{
-	WriteVTKHeader(file, discLines, numLines, precision, header_info, meshT, discLines_scaling);
-	for (unsigned int n=0; n<numFields; ++n)
-	{
-		WriteVTKScalarArray(file, names[n], array[n], numLines, precision);
-		file << endl;
-	}
-	return true;
-}
-
-
 bool ProcessFields::WriteMesh2HDF5(string filename, string groupName, unsigned int const* numLines, double const* const* discLines, MeshType meshT, double discLines_scaling)
 {
 	H5::H5File file( filename, H5F_ACC_RDWR );
diff --git a/Common/processfields.h b/Common/processfields.h
index db7a5e8..01575db 100644
--- a/Common/processfields.h
+++ b/Common/processfields.h
@@ -67,22 +67,6 @@ public:
 	//! Set dump type: 0 for E-fields, 1 for H-fields, 2 for D-fields, 3 for B-fields, 4 for J-fields, etc...
 	void SetDumpType(DumpType type) {m_DumpType=type;}
 
-	//! Write a vtk header to an already open file with given mesh-type
-	static void WriteVTKHeader(ofstream &file, double const* const* discLines, unsigned int const* numLines, unsigned int precision=12, string header_info = string(), MeshType meshT = CARTESIAN_MESH, double discLines_scaling = 1);
-	//! Write a vtk header to an already open file (cartesian grid)
-	static void WriteVTKCartesianGridHeader(ofstream &file, double const* const* discLines, unsigned int const* numLines, unsigned int precision=12, string header_info = string(), double discLines_scaling = 1);
-	//! Write a vtk header to an already open file (cylindrical grid)
-	static void WriteVTKCylindricalGridHeader(ofstream &file, double const* const* discLines, unsigned int const* numLines, unsigned int precision=12, string header_info = string(), double discLines_scaling = 1);
-	//! Append a vtk vector array to an already open vtk file, write a header first! \sa WriteVTKHeader()
-	static void WriteVTKVectorArray(ofstream &file, string name, FDTD_FLOAT const* const* const* const* array, double const* const* discLines, unsigned int const* numLines, unsigned int precision=12, MeshType meshT = CARTESIAN_MESH);
-	//! Append a vtk scalar array to an already open vtk file, write a header first! \sa WriteVTKHeader()
-	static void WriteVTKScalarArray(ofstream &file, string name, FDTD_FLOAT const* const* const* array, unsigned int const* numLines, unsigned int precision=12);
-
-	static bool DumpVectorArray2VTK(ofstream &file, string name, FDTD_FLOAT const* const* const * const* array, double const* const* discLines, unsigned int const* numLines, unsigned int precision=12, string header_info = string(), MeshType meshT = CARTESIAN_MESH, double discLines_scaling = 1);
-	static bool DumpMultiVectorArray2VTK(ofstream &file, string names[], FDTD_FLOAT const* const* const* const* const* array, unsigned int numFields, double const* const* discLines, unsigned int const* numLines, unsigned int precision=12, string header_info = string(), MeshType meshT = CARTESIAN_MESH, double discLines_scaling = 1);
-	static bool DumpScalarArray2VTK(ofstream &file, string name, FDTD_FLOAT const* const* const* array, double const* const* discLines, unsigned int const* numLines, unsigned int precision=12, string header_info = string(), MeshType meshT = CARTESIAN_MESH, double discLines_scaling = 1);
-	static bool DumpMultiScalarArray2VTK(ofstream &file, string names[], FDTD_FLOAT const* const* const* const* array, unsigned int numFields, double const* const* discLines, unsigned int const* numLines, unsigned int precision=12, string header_info = string(), MeshType meshT = CARTESIAN_MESH, double discLines_scaling = 1);
-
 	//! Write a mesh information to the given hdf5-group
 	static bool WriteMesh2HDF5(string filename, string groupName, unsigned int const* numLines, double const* const* discLines, MeshType meshT = CARTESIAN_MESH, double discLines_scaling = 1);
 
diff --git a/Common/processfields_sar.cpp b/Common/processfields_sar.cpp
index 76a8f0a..4beb080 100644
--- a/Common/processfields_sar.cpp
+++ b/Common/processfields_sar.cpp
@@ -17,6 +17,7 @@
 
 #include "processfields_sar.h"
 #include "operator_base.h"
+#include "tools/vtk_file_io.h"
 
 ProcessFieldsSAR::ProcessFieldsSAR(Engine_Interface_Base* eng_if) : ProcessFieldsFD(eng_if)
 {
@@ -81,12 +82,6 @@ double ProcessFieldsSAR::GetKappaDensityRatio(const unsigned int* pos)
 
 void ProcessFieldsSAR::DumpFDData()
 {
-#ifdef OUTPUT_IN_DRAWINGUNITS
-	double discLines_scaling = 1;
-#else
-	double discLines_scaling = Op->GetGridDelta();
-#endif
-
 	unsigned int pos[3];
 	FDTD_FLOAT*** SAR = Create3DArray<float>(numLines);
 	std::complex<float>**** field_fd = NULL;
@@ -112,12 +107,13 @@ void ProcessFieldsSAR::DumpFDData()
 		if (m_fileType==VTK_FILETYPE)
 		{
 			stringstream ss;
-			ss << m_filename << fixed << "_f=" << m_FD_Samples.at(n) << ".vtk";
-			ofstream file(ss.str().c_str());
-			if (file.is_open()==false)
-				cerr << "ProcessFieldsSAR::DumpFDData: can't open file '" << ss.str() << "' for writing... abort! " << endl;
-			DumpScalarArray2VTK(file,GetFieldNameByType(m_DumpType),SAR,discLines,numLines,m_precision,string("Interpolation: ")+m_Eng_Interface->GetInterpolationTypeString(), m_Mesh_Type, discLines_scaling);
-			file.close();
+			ss << m_filename << fixed << "_f=" << m_FD_Samples.at(n);
+
+			m_Dump_File->SetFilename(ss.str());
+			m_Dump_File->ClearAllFields();
+			m_Dump_File->AddScalarField(GetFieldNameByType(m_DumpType),SAR,numLines);
+			if (m_Dump_File->Write()==false)
+				cerr << "ProcessFieldsSAR::Process: can't dump to file... abort! " << endl;
 		}
 		else if (m_fileType==HDF5_FILETYPE)
 		{
diff --git a/FDTD/operator.cpp b/FDTD/operator.cpp
index aab6985..7064a2c 100644
--- a/FDTD/operator.cpp
+++ b/FDTD/operator.cpp
@@ -22,6 +22,7 @@
 #include "extensions/operator_ext_excitation.h"
 #include "Common/processfields.h"
 #include "tools/array_ops.h"
+#include "tools/vtk_file_io.h"
 #include "fparser.hh"
 
 Operator* Operator::New()
@@ -404,13 +405,6 @@ void Operator::DumpOperator2File(string filename)
 	double discLines_scaling = GetGridDelta();
 #endif
 
-	ofstream file(filename.c_str(),ios_base::out);
-	if (!file.is_open())
-	{
-		cerr << "Operator::DumpOperator2File(): Can't open file: " << filename << endl;
-		return;
-	}
-
 	cout << "Operator: Dumping FDTD operator information to vtk file: " << filename << " ..." << flush;
 
 	FDTD_FLOAT**** exc = Create_N_3DArray<FDTD_FLOAT>(numLines);
@@ -437,18 +431,23 @@ void Operator::DumpOperator2File(string filename)
 					ii_temp[n][pos[0]][pos[1]][pos[2]] = GetII(n,pos);
 				}
 
-	string names[] = {"vv", "vi", "iv" , "ii", "exc"};
-	FDTD_FLOAT**** array[] = {vv_temp,vi_temp,iv_temp,ii_temp,exc};
+	VTK_File_IO* vtk_io = new VTK_File_IO(filename.c_str(), m_MeshType);
+	vtk_io->SetMeshLines(discLines,numLines,discLines_scaling);
+	vtk_io->SetHeader("openEMS - Operator dump");
 
-	ProcessFields::DumpMultiVectorArray2VTK(file, names , array , 5, discLines, numLines, 6, "Operator dump" , (ProcessFields::MeshType)m_MeshType, discLines_scaling);
-
-	Delete_N_3DArray(ii_temp,numLines);
-	Delete_N_3DArray(iv_temp,numLines);
-	Delete_N_3DArray(vi_temp,numLines);
+	vtk_io->AddVectorField("vv",vv_temp,numLines);
 	Delete_N_3DArray(vv_temp,numLines);
+	vtk_io->AddVectorField("vi",vi_temp,numLines);
+	Delete_N_3DArray(vi_temp,numLines);
+	vtk_io->AddVectorField("iv",iv_temp,numLines);
+	Delete_N_3DArray(iv_temp,numLines);
+	vtk_io->AddVectorField("ii",ii_temp,numLines);
+	Delete_N_3DArray(ii_temp,numLines);
+	vtk_io->AddVectorField("exc",exc,numLines);
 	Delete_N_3DArray(exc,numLines);
 
-	file.close();
+	if (vtk_io->Write()==false)
+		cerr << "Operator::DumpOperator2File: Error: Can't write file... skipping!" << endl;
 
 	cout << " done!" << endl;
 }
@@ -458,13 +457,6 @@ void Operator::DumpOperator2File(string filename)
 //! visualize only one component (x, y or z)
 void Operator::DumpPEC2File( string filename )
 {
-	ofstream file( filename.c_str() );
-	if (!file.is_open())
-	{
-		cerr << "Operator::DumpPEC2File(): Can't open file: " << filename << endl;
-		return;
-	}
-
 	cout << "Operator: Dumping PEC information to vtk file: " << filename << " ..." << flush;
 
 	FDTD_FLOAT**** pec = Create_N_3DArray<FDTD_FLOAT>( numLines );
@@ -533,9 +525,16 @@ void Operator::DumpPEC2File( string filename )
 #else
 	scaling = GetGridDelta();
 #endif
-	ProcessFields::DumpVectorArray2VTK( file, "PEC", pec, discLines, numLines, 6, "PEC dump" , (ProcessFields::MeshType)m_MeshType, scaling );
 
-	file.close();
+	VTK_File_IO* vtk_io = new VTK_File_IO(filename.c_str(), m_MeshType);
+	vtk_io->SetMeshLines(discLines,numLines,scaling);
+	vtk_io->SetHeader("openEMS - PEC dump");
+
+	vtk_io->AddVectorField("PEC",pec,numLines);
+	Delete_N_3DArray(pec,numLines);
+
+	if (vtk_io->Write()==false)
+		cerr << "Operator::DumpPEC2File: Error: Can't write file... skipping!" << endl;
 
 	cout << " done!" << endl;
 }
@@ -548,13 +547,6 @@ void Operator::DumpMaterial2File(string filename)
 	double discLines_scaling = GetGridDelta();
 #endif
 
-	ofstream file(filename.c_str(),ios_base::out);
-	if (!file.is_open())
-	{
-		cerr << "Operator::DumpMaterial2File(): Can't open file: " << filename << endl;
-		return;
-	}
-
 	cout << "Operator: Dumping material information to vtk file: " << filename << " ..."  << flush;
 
 	FDTD_FLOAT**** epsilon = Create_N_3DArray<FDTD_FLOAT>(numLines);
@@ -582,17 +574,21 @@ void Operator::DumpMaterial2File(string filename)
 		}
 	}
 
-	string names[] = {"epsilon","mue","kappa","sigma"};
-	FDTD_FLOAT**** array[] = {epsilon,mue,kappa,sigma};
-
-	ProcessFields::DumpMultiVectorArray2VTK(file, names, array, 4, discLines, numLines,  6, "Material dump" , (ProcessFields::MeshType)m_MeshType, discLines_scaling);
+	VTK_File_IO* vtk_io = new VTK_File_IO(filename.c_str(), m_MeshType);
+	vtk_io->SetMeshLines(discLines,numLines,discLines_scaling);
+	vtk_io->SetHeader("openEMS - material dump");
 
+	vtk_io->AddVectorField("epsilon",epsilon,numLines);
 	Delete_N_3DArray(epsilon,numLines);
+	vtk_io->AddVectorField("mue",mue,numLines);
 	Delete_N_3DArray(mue,numLines);
+	vtk_io->AddVectorField("kappa",kappa,numLines);
 	Delete_N_3DArray(kappa,numLines);
+	vtk_io->AddVectorField("sigma",sigma,numLines);
 	Delete_N_3DArray(sigma,numLines);
 
-	file.close();
+	if (vtk_io->Write()==false)
+		cerr << "Operator::DumpMaterial2File: Error: Can't write file... skipping!" << endl;
 
 	cout << " done!" << endl;
 }
@@ -838,11 +834,11 @@ int Operator::CalcECOperator( DebugFlags debugFlags )
 		m_Op_exts.at(n)->BuildExtension();
 
 	if (debugFlags & debugMaterial)
-		DumpMaterial2File( "material_dump.vtk" );
+		DumpMaterial2File( "material_dump" );
 	if (debugFlags & debugOperator)
-		DumpOperator2File( "operator_dump.vtk" );
+		DumpOperator2File( "operator_dump" );
 	if (debugFlags & debugPEC)
-		DumpPEC2File( "PEC_dump.vtk" );
+		DumpPEC2File( "PEC_dump" );
 
 	//cleanup
 	for (int n=0; n<3; ++n)