Five Sambhogakaya Buddhas
Vairocana (Tib., Nampar Nangdza; rNam-par sNang-mDzad) center
Akshobhya (Tib., Mikyopa; Mi-bsKyod-pa) east
Ratnasambhava (Tib., Rinchenjungdan; Rin-chen-hByung-lDan) south
Amitabha (Tib., Opame; hOd-dpag-med) west
Amoghasiddhi (Tib., Donjodubpa; Don-yod-Grub-pa) north
In the drawing, the central blue plane represents the sambhogakaya realm, indicating the five directions in which the above Buddhas manifest as visionary beings representing the all-encompassing Adibuddha (here symbolized by the three-dimensional sphere).
Each of these Buddhas represents one of the five families and each also has a so-called 'spiritual son' (or two): Bodhisattvas who represent the active energy of the respective Sambhogakaya Buddha by way of their (Nirmanakaya) manifestations and incarnations.
Note: There are other collective Sanskrit names in use for these five deities: tathagathas and jinas. Also, there are other systems of organization - mostly with Vairocana changing positions (center/east) with Akshobhya.