To purify eyes and to improve eye vision by strengthening eyes muscles one can practice Trataka yoga and meditation.
This yoga technique helps to sleep and improves focus, improves weak eyesight and concentration.
It also improves ability to visualize and willpower. It is a cleansing practice of yoga that helps to gain the energy.
How to perform Trataka?
There are three phases to practice trataka. Before getting into phase sit in meditation pose.
First phase: Fix your gaze on a moving object and hold it for a minute or two. If your mind starts thinking about something, notice the thought and let it go. Try to keep the eyes open. If eyes are tired and watery close the eyes gently and let the heat release through watery eyes. After a minute or two move into second phase.
Second phase: Light an traditional oil lamp or candle. Keep the candle at your chest level at arm length. Watch the flame by keeping eyes still. Candle will have three different colors. Base is reddish, middle is white and upper part is somewhat bright followed by slight smoke at tip. Concentrate on brighter part by focusing your eyes. Once eyes feel tired gently close the eyes. When you close the eyes image of flame appears within. Concentrate on that image but do not try to hold the image within with pressure as it fades away. Having image within concentrate on your meditation.
Third phase: This involves Sun, raising Sun. Morning apply little ghee (clarified butter) on your eyes and look at Sun only when it is red or orange and still Sun is touching horizon. Stare at Sun during Sun raise if it does not hurt your eyes and you should be able to keep your eyes fixed on raising Sun. This practice takes about 10 minutes either morning or one can stare at Sun during Sun setting time in the evening. When your eyes are tired and watery gently close the eyes, and go through meditation.
Practicing trataka not only is beneficial for eyes, it is relaxing for the mind as outside noise and distraction will be disconnected during practice.
**Trataka is not recommended for those who are psychologically affected and suffering from mental trauma.