초록 ▼

An apparatus for removing tissue from the eye performs various types of corrections using a relatively large beam, but oscillated or dithered to prevent the formation of ridges during the removal process. Various types of corrections are contemplated such as hyperopic and astigmatic using a large be

An apparatus for removing tissue from the eye performs various types of corrections using a relatively large beam, but oscillated or dithered to prevent the formation of ridges during the removal process. Various types of corrections are contemplated such as hyperopic and astigmatic using a large beam which is scanned over the area to be ablated using overlapping shots which are between 10% and 90% of the area of the total area to be ablated.

대표청구항 ▼

An apparatus for shaping the cornea by removing tissue from a region of the cornea in which tissue is to be removed to achieve a desired corneal profile of the region for correction of vision, the region having a total treatment area, the region having a center of treatment on the cornea, the appara

An apparatus for shaping the cornea by removing tissue from a region of the cornea in which tissue is to be removed to achieve a desired corneal profile of the region for correction of vision, the region having a total treatment area, the region having a center of treatment on the cornea, the apparatus comprising: (a) a laser that emits a laser beam having a suitable wavelength for ablation of corneal tissue; (b) an optical system coupled to said laser that images said laser beam onto the cornea forming a laser spot on the cornea of a variable size on the cornea and at a variable location on the cornea, the laser spot being imaged on the cornea having a laser spot area and the laser spot having a center; and (c) a control unit coupled to said optical system and to said laser for directing the optical system to perform a course of treatment upon the region of the cornea by varying the size and location of said laser spot, said control unit, according to the tissue to be removed from the region of the cornea to achieve the desired corneal profile, limiting the size of said laser spot such that during the course of treatment, the laser spot achieves a maximum laser spot area of between approximately 10% and 90% of the total treatment area of the region in which tissue is to be removed, and said control unit further directing said optical system to move the center of the laser spot over a portion of the region in which tissue is to be removed to at least one location on the cornea away from the center of treatment of the region of the cornea such that the formation of large ridges in the region of the cornea is avoided and such that the laser spot area on the cornea changes at least once during the course of treatment.