A simple viewer to save the eyes .. as it is very powerful here
A very safe way to look at the partial phases of a total solar eclipse is to construct a basic pinhole projection. A pinhole projection is the result of light traveling through a small hole and projecting an image of itself against a light colored surface.
You can create a pinhole shield with a piece of paper or cardboard. Poke a hole in paper using a pencil point. The pinhole only needs to be a couple of millimeters across and should be as round as possible. Try not to leave jagged edges if punching the hole through cardboard or some other stiff material.
Pinhole effects can be observed during an eclipse in a variety of places. The shadow through a tree can create a myriad of pinhole images. Loosely woven hats with lots of small holes are a favorite of many eclipse-chasing veterans.
Another interesting technique is to punch several pinholes in the paper so that multiple eclipse images appear on the projected surface. Don't put the holes too close to each other as that will cause the images to overlap.
The projection technique can also be applied to a telescope or binoculars. That is, an image from the eyepiece can be projected to a surface and the sun studied in detail. Someone very knowledgeable about his or her telescope can do this for you and some small telescopes are sold with solar projection attachments. Under no circumstances should you look through the telescope unless directed so by an expert at solar observing (and make sure there is a filter attached in the proper place!). http://www.eclipse-chasers.com/safe.htm