The invention relates to a laser treatment unit for performing eye surgery, comprising a contact glass (23), which can be placed onto the eye (21) and via which a treatment laser beam (2) passes. A safety mechanism (24, 25) is provided that displaceably holds the contact glass (23) in such a manner that the contact glass retreats when the contact glass (23) is subjected to the action of a force contrary to the direction of incidence of the laser beam. The safety mechanism (24, 25) enables this retreating when a force is greater than a force limit value (Fmin) and holds the contact glass (23) in a fixed manner when the force is less than the force limit value.
