The problem seems to be that the normals of the two faces that connect the horizontal bars of the letter E are pointing into the opposite direction as the rest of the front facing part of the E.
Make sure the normals of your meshes are consistent (meaning that the normals of two neighboring faces are pointing to the same side of the volume, optimally outside).
The normals are used for lighting calculations. Since the direction of the normals is inconsistent over the front of the E, the lighting calculations generate artifacts.
Do you really need these faces? They make the E look like a block. If not you can delete them.
Otherwise you need to flip the normals of the faces or separate the faces from the rest of the mesh. You can flip the normals by selecting the two faces and clicking the
Flip Direction button in the toolbar to the right side of the 3D view. If the toolbar is not visible press [T] while your mouse cursor is in the 3D view.
The result should look like this:
To separate the faces instead select them and press [Y].
Both methods ensure the normals of the E are consistent on the front face:
In general you should avoid non-manifold meshes. A mesh is called non-manifold if an edge connects more than two faces. Just imagine your mesh was made out of a rubber sheet. If you can cut out a region around any edge and find a way to press it flat onto the table without faces overlapping, your mesh is manifold and you are ready for production.
If you have a manifold mesh, Blender can even calculate the normals for you: Go into editmode, select the faces whose normals you want to calculate and press [Ctrl+N] to calculate the outwards facing normals or [Ctrl+Shift+N] to calculate the normals facing inside.