Patent ID: 9554943
Date: 2017-01-31
CPC Classifications: A61B,A61F

Claim:
1. An ophthalmic instrument for the application of laser radiation in an eye, for the examination and/or surgical laser treatment of the cornea and the lens of the eye, comprising: a femtosecond laser as a radiation source for laser radiation, a contact glass with a concave contact surface that is applied onto the cornea to suppress eye movement, an optical entrance system having a refractive power ratio that is variable; an objective from which a beam emerges that is focused in the direction of the eye, optical assemblies which are arranged in front of the objective as seen in the beam direction, and which in operative connection with the objective selectively vary the focus position in the coordinate direction X,Y and Z either within the region of the cornea or within the region of the lens of the eye, the objective being movable relative to the eye or having at least one lens group the position of which relative to the eye is variable, the variation of the position of the lens group or of the entire objective shifting the focus position from the region of the cornea to the region of the lens of the eye and vice versa; the optical entrance system including at least one optical element that is shiftable between a first position and a second position such that shifting of the at least one optical element varies an aperture angle α on a side proximate the eye by variation of the refractive power ratio of the optical entrance system and, thereby, a diameter of the beam emerging from the optical entrance system is also variable, the aperture angle α being smaller when the focus position is in the region of the lens of the eye than when the focus position is in the region of the cornea.