초록 ▼

A closed-loop control system for the superficial photoablation of stromal tissue from an exposed surface includes an active mirror for directing a diagnostic laser beam through the exposed surface to a focal point on the retina of an eye. The reflected beam is analyzed by a detector to identify a di

A closed-loop control system for the superficial photoablation of stromal tissue from an exposed surface includes an active mirror for directing a diagnostic laser beam through the exposed surface to a focal point on the retina of an eye. The reflected beam is analyzed by a detector to identify a distorted wavefront that is indicative of required corrections, and an induced wavefront that is indicative of optical aberrations that have been mechanically introduced when the stromal tissue was exposed. A compensator alters a desired wavefront with the induced wavefront to create a rectified wavefront. A comparator then compares the rectified wavefront with the distorted wavefront to create an error signal. In the operation of the closed-loop control system, the error signal is used to maintain a focal point on the retina for the diagnostic laser beam. Also, at a null, the error signal indicates when the required amount of stromal tissue has been photoablated.

대표청구항 ▼

1. A closed-loop control system for superficial photoablation of tissue from an exposed stromal surface of an eye wherein the exposed surface introduces mechanically induced optical aberrations, said system comprising:a source for generating an incising laser beam to photoablate tissue from the expo

1. A closed-loop control system for superficial photoablation of tissue from an exposed stromal surface of an eye wherein the exposed surface introduces mechanically induced optical aberrations, said system comprising:a source for generating an incising laser beam to photoablate tissue from the exposed surface; a source for generating a diagnostic laser beam; a deformable mirror for directing said diagnostic laser beam through the exposed stromal surface to a focal spot on the retina of the eye; a detector for using light from said diagnostic beam reflected from the retina through the exposed stromal surface to generate an induced wavefront having characteristics of the mechanically induced optical aberrations, together with a distorted wavefront having actual real-time characteristics of the cornea; a compensator for altering a predetermined desired wavefront by incorporating said induced wavefront therewith to create a rectified wavefront; a comparator for comparing said rectified wavefront with said distorted wavefront to create an error signal; a means for reconfiguring said deformable mirror in accordance with said error signal to maintain said focal spot on the retina; and a means for ceasing generation of said incising laser beam when said error signal is a null.