The author Timothy Dawson, an expert in medieval armor and combat techniques, presents a convincing portrait of the cavalry of the Eastern Empire. They played a diverse number of tactical roles - many were equipped for skirmishing or scouting missions, while others were equipped for close combat.
The Byzantines copied the fighting styles of Turkish cavalry - fighting unarmored and with composite bows - but not with the same great effect. The tradition of the kataphractos - the heavily equipped lancer dating (in the Roman Army) to at least the 2nd Century AD remained intact up to the beginning of the Empire's terminal decline in the early 13th Century.
This is a detailed and highly recommendable look into the cavalrymen of the Byzantine Empire, examining both the armor and the personal life of the man that wore it; it is a well-researched source on the elite defenders of a declining Empire that faced enemies as diverse as Turkish tribesmen and Frankish crusaders.