The Three Pure Ones worshipped in the Taoist altar are

Yuqing, Shangqing, Taqing  The Three Pure Ones refer to the three Pure Realms of Taoism, namely Yuqing, Shangqing, and Taqing. They also refer to the three supreme deities residing in the Three Pure Realms, which are: 12 Yuqing Yuan Shi Tianzun, Shangqing Ling Bao Tianzun, Taqing Dao De Tianzun (Tai Shang Laojun). The Three Pure Lords govern all the immortals in the Three Pure Realms and also govern all things in the world, being the highest deities in Taoism. Among them, the Yuqing Realm is formed from the primordial qi of the Great Luo Heaven, and the celestial beings within it are governed by Yuqing Yuan Shi Tianzun; the Shangqing Realm is formed from the original qi of the Great Luo Heaven,