Curving correcting carving apparatus of cornea

Abstract

Abstract PURPOSE: To improve the quality of correction of a curvature, using an excimer laser for producing a beam having a cross-sectional shape and having a long width and a low height, and by providing an optically enlarging means for enlarging the height and a beam rotating means for rotating thus enlarged beam about the axis thereof in a light beam uniforming means. CONSTITUTION: Excimer laser emits a parallel beam 10 having dimensions of 22mm×7mm. A beam uniforming and shaping means 22 includes a scraper 20 for removing crosswise stripes of light intensity, a light beam enlarging pair of strain shape elements 50 to 51, a scraper 53 having a hole for reducing a transmitted beam into a circular cross-sectional shape, an optical filter 55 and a beam rotating device 52. The strain shape light beam enlarging elements 50 to 51 enlarge the height up to a value equal to the width W' so that a rectangular cross-sectional beam is turned into a square cross-sectional shape. Next, the beam passes through the optical filter 55 having a transmittance which is axially uniform, and a transmittance which is not uniform in the orthogonal direction and axially symmetric. Further, the pulse shape exhibits a cumulative irregularity, and accordingly, a beam rotary element 52 for compensating for a lowered value is used.

Inventors

• 👤 Bii Terufueaa Uiriamu
• 👤 Aaru Yodaa Jiyuniaa Pooru
• 👤 Ei Maatein Kurifuoodo

Bibliographic Details