Patent ID: 8277060

Claim:
An apparatus for shaping a laser beam profile, comprising: a reformatting optical system configured to reformat a laser beam having a Gaussian intensity profile into a radiation beam having a top hat intensity profile; and an optical system configured to Fourier transform the radiation beam having the top hat intensity profile into a radiation beam having a Bessel or sinc function intensity profile, the optical system including a first mirror, a second mirror and a third mirror, the first mirror configured to receive the radiation beam having the top hat intensity profile from the reformatting optical system and reflect the radiation beam towards the second mirror, the second mirror configured to reflect the radiation beam received from the first mirror towards the third mirror, and the third mirror is configured to direct the radiation beam received from the second mirror towards an output of the Fourier transforming optical system; wherein the first mirror and the second mirror form a high telephoto ratio Cassegrain optical system, in which the physical length between the first mirror and the second mirror is reduced by a factor of at least 20 as compared to a conventional f-f Fourier transform configuration.