There is no significant energy loss in the total internal reflection and the reflected ray has entire light wave energy so that a brighter image is formed, but some energy in the plane mirror is absorbed inside and thus energy loss.
Explanation:
Advantages
If the light is reflected from the total prism, the entire light is completely reflected internally. But only about 90% of the incident light is reflected from the mirror of the plane. Consequently, reflected light intensity is more in the prism than light reflected in the plane mirror.
There are no more reflections in the prism as in the plane mirror in its entirety.
In the case of a total prism as in the plane mirror, the image is not reversed laterally.
