diff --git a/DiffractionGratings/grating2D.geo b/DiffractionGratings/grating2D.geo
index db87e8e1ed5751096e727cf398dfd0d0b9baf626..0ce73daee78ed3432e0538e062c51ebc1c963677 100644
--- a/DiffractionGratings/grating2D.geo
+++ b/DiffractionGratings/grating2D.geo
@@ -196,14 +196,9 @@ last_surf_list={};
 phys_rod_list={};
 
 If(Flag_glue_rod_subs==0)
-  phys_plot_bnd={14,18,22,26};
   For k1 In {0:N_rods-1:1}
     last_surf_list[k1]  = istart+k1;
     phys_rod_list[k1] = istart+k1;
-    phys_plot_bnd[5+4*k1+0]=istart+4*k1+0;
-    phys_plot_bnd[5+4*k1+1]=istart+4*k1+1;
-    phys_plot_bnd[5+4*k1+2]=istart+4*k1+2;
-    phys_plot_bnd[5+4*k1+3]=istart+4*k1+3;
   EndFor
   last_surf_list[N_rods] = 70;
   Plane Surface(72) = last_surf_list[];
@@ -211,35 +206,29 @@ EndIf
 
 If(Flag_glue_rod_subs==1)
   If(Shape_rod==0)
-    phys_plot_bnd={14,90,101,91,22,26};
     For k1 In {1:N_rods-1:1}
       last_surf_list[k1-1]  = istart+k1;
     EndFor
     For k1 In {0:N_rods-1:1}
       phys_rod_list[k1] = istart+k1;
-      phys_plot_bnd[7+4*k1+0]=istart+4*k1+0;
-      phys_plot_bnd[7+4*k1+1]=istart+4*k1+1;
-      phys_plot_bnd[7+4*k1+2]=istart+4*k1+2;
-      phys_plot_bnd[7+4*k1+3]=istart+4*k1+3;
     EndFor
     last_surf_list[N_rods-1] = 70;
     Plane Surface(72) =-last_surf_list[];	
   EndIf
   If(Shape_rod==1)
-    phys_plot_bnd={14,90,91,22,26};
     For k1 In {0:N_rods-1:1}
     last_surf_list[k1]  = istart+k1;
     phys_rod_list[k1] = istart+k1;
-    phys_plot_bnd[6+4*k1+0]=istart+4*k1+0;
-    phys_plot_bnd[6+4*k1+1]=istart+4*k1+1;
-    phys_plot_bnd[6+4*k1+2]=istart+4*k1+2;
-    phys_plot_bnd[6+4*k1+3]=istart+4*k1+3;
     EndFor
     last_surf_list[N_rods] = 70;
     Plane Surface(72) = last_surf_list[];
   EndIf
 EndIf
 
+eps=3*nm;
+phys_plot_bnd() = Curve In BoundingBox{-d/2-eps,-h_sub-eps,-eps, d/2+eps, h_layer_dep+h_pc+h_layer_cov+h_sup+eps , eps};
+
+
 Periodic Line {8,12,16,20,24,28,32} = {1,2,3,4,5,6,7} Translate {d,0,0} ;
 
 Physical Line(SURF_BLOCH_X_LEFT)  = {1, 2, 3, 4, 5, 6, 7}; // Bloch_LeftX-
@@ -248,7 +237,7 @@ Physical Line(SURF_INTEG_SUP1) = {30};                     // super/pml cut
 Physical Line(SURF_INTEG_SUP2) = {26};                     // super/grooves cut
 Physical Line(SURF_INTEG_SUB1) = {10};                     // subs/pml cut
 Physical Line(SURF_INTEG_SUB2) = {14};                     // cov/subs cut
-Physical Line(SURF_PLOT) = phys_plot_bnd[];                // final plot
+Physical Line(SURF_PLOT) = phys_plot_bnd();                // final plot
 
 Physical Surface(PMLBOT)   = {36}; // pmlbot
 Physical Surface(SUB)      = {38}; // sub