What is an excimer laser?
An excimer laser is controlled by a computer, allowing for precise cutting of the cornea. The excimer laser emits an ultraviolet, non-thermal (cold), invisible beam, which is so precise it can remove 39 millionth of an inch of tissue in 12 billionth of a second, according to the US Food and Drug Administration (FDA). The excimer laser has been used in photorefractive keratectomy (PRK) and was approved for use in LASIK surgery by the FDA in 1998. How is LASIK surgery performed? Although each procedure varies slightly, in general, LASIK surgery involves using a computer-controlled excimer laser (a cold, ultraviolet laser) and a microkeratome (a surgical instrument). With these instruments, the surgeon cuts a flap in the center of the cornea to remove a thin layer of tissue. By removing the tissue, the cornea flattens, reducing the myopia. The flap, which is replaced without using sutures, adheres back to the cornea within minutes. Recovery after LASIK surgery In most cases, recovery from
A laser is an instrument that can produce and control a powerful beam of light. Laser light can be directed and controlled more precisely than normal light, and it can be delivered in extremely brief, intense pulses. The excimer laser produces a beam of ultraviolet light in pulses that last only a few billionths of a second. Each pulse removes a microscopic amount of tissue by evaporating it, producing very little heat and leaves underlying tissue virtually unchanged.
An excimer laser is the type of laser that is used to modify or shape the front surface of the eye in order to make people see better without glasses or contact lenses. There are other types of lasers used in ophthalmology, such as the Argon laser which is used to treat diabetic retinopathy, and the Yag laser, which is used to treat membranes within the eye. The excimer laser is specifically designed to sculpt or reshape the cornea to allow light to focus more clearly without the aid of glasses or contact lenses.
An excimer laser is a kind of gas laser excited by mainly using pulse discharge via a mixture of rare gases and halogen gas as a medium. Krypton Fluoride (KrF) and Argon Fluoride (ArF) excimer laser light sources allow emission of high-intensity deep UV (DUV) light at the wavelengths of 248 nm and 193 nm, respectively. They are used as light sources for leading-edge lithography tools that require high resolution. Because an excimer laser has a wide spectral bandwidth, its imaging performance previously was not good when used for lithography tools. But development of a line-narrowing technology using grating has enabled emission of DUV at an extremely narrow band of sub-pm while maintaining high luminous intensity, thereby achieving a performance that is optimum for lithography tool optics. (For your reference) For more information on the technologies of Gigaphoton, see our Technology page.
