An ophthalmological device (1) includes an optical transmission system (5) for transmitting femtosecond laser pulses (L) onto a projection lens (3) for projection onto or into the eye tissue (21). The device (1) also includes a lens interchange device (4) designed for interchanging and connecting different projection lenses (3) to the optical transmission system (5). The lens interchange device (4) includes a number of different projection lenses (3) which are connected mechanically to one another and which can be fed to the optical transmission system (5) by a rotational or translational movement in order to connect the former to the optical transmission system (5). The lens interchange device (4) makes it possible for a user to flexibly and efficiently change the projection lens (3) so that the projection lens (3) can be changed or altered without great expenditure of time and without using a varifocal lens, even between different applications and treatment steps.