There are variety of products that will help achieve total, or close to, total darkness in your room:
Have a great light-blocking option with their opaque material which will give you near 100% darkness.
With Block out lining, these will help give close to 100% room darkening effect while being able to custom select the fabric that matches your room’s décor.
Unlike shades that are either up or down, shutters have a great light control option. When closed they achieve near 100% block out; when opened they can fill a room with light. This is a great option for bedrooms.
Custom made to your fabric with room darkening lining; drapes are a great light blocking option. Standing alone or as an addition to existing window treatments, they will completely darken your room.