A Prospective Safety and Effectiveness Study of the 500 Hz Technolas Perfect Vision Excimer Laser Using LASIK

Inclusion Criteria: * Subjects have to be at least 18 years of age. * Subjects have to be able to read, understand, and sign a statement of Informed Consent. * Subjects have to be willing and able to return for scheduled follow-up examinations for up to 6 and 12 months respectively after surgery. * Corneal topography should be qualified * High contrast, manifest, best spectacle-corrected distance visual acuity correctable binocular to at least 1.0 (Snellen 20/20 or 6/6) and monocular to at least 0.8 (Snellen 20/25 or 6/7.5). In case of a monocular surgery the eye which should not be treated must have a best corrected distance visual acuity of at least 0.8 (Snellen 20/25 or 6/7.5). * Mesopic pupil size measured with the Zywave II WaveFront Aberrometer must be \< 7.0 mm and photopic pupil size measured with the Orbscan II/ IIz must be \> 2.9 mm. * Myopic subjects require a sphere between -0.5 D up to -10.0 D and cylinder between -0.5 D up to -4.0 D (not corneal astigmatism) and SE up to -12.0 D * Hyperopic subjects require a sphere between +0.5 D up to +4.0 D and cylinder between +0.5 D up to +4.0 D (not corneal astigmatism) and SE up to +6.0 D. Exclusion Criteria: * Subjects for whom the combination of their baseline corneal thickness and the planned operative parameters for the LASIK procedure would result in less than 250 microns of remaining posterior corneal thickness below the flap postoperatively. * Hyperopic eyes for which the baseline manifest subjective refraction exhibits a difference of greater than ± 0.75 D in sphere power, or a difference of greater than ± 0.50 D in cylinder power, or a difference in cylinder axis of more than 15 degrees compared to the baseline cycloplegic subjective refraction. For manifest cylinder of less than ±0.75 D, the differ-ence in cylinder axis would not be taken into consideration. * Subjects with anterior segment pathology, including dry eye syndrome and cataracts, which in the Investigator's opinion would interfere with best spectacle-corrected visual acuity or a successful treatment. * Subjects with evidence of retinal vascular disease. Subjects with any residual, recurrent, or active ocular disease, or corneal abnormality that in the Investigator's opinion would interfere with BSCVA or a successful treatment. * Subjects with signs of keratoconus or Subjects with unstable central keratometry readings with irregular mires. * Subjects who had previous intraocular or corneal surgery of any kind, including any type of Excimer laser surgery for either refractive or therapeutic purposes. * Subjects who have a history of Herpes simplex or Herpes zoster keratitis or history of glaucoma or glaucoma suspect, corneal edema, or increased IOP \> 22mmHg or risk for angle closure. * Subjects immunocompromised or carrying diagnosis of connective tissue disease, clinically significant atopic disease, diabetes, autoimmune diseases and other acute or chronic illnesses that will increase the risk to the subject or confound the outcomes of this study. * Subject taking systemic medications likely to affect wound healing such as corticosteroids or antimetabolites. * Subjects who are known to be pregnant, lactating, or who plans to become pregnant over the course of the study. * Subjects with an ocular muscle disorder including a strabismus or nystagmus, or other disorders affecting fixation. * Subjects with cognitive impairments or other vulnerable persons.