Design of a phase-filtering mask and an aspherical lens for uniform irradiance and phase on target

摘要

We propose two designs with which one can obtain a circular light disk with both uniform irradiance and phase, namely, a homodisk on a plane target from a TEM↓（0，0） Gaussian beam. The first design is pure-phase filtering masks based on wave theory and computer simulation. The second design,an aspherical lens, satisfies the two requirements successively. We used geometrical optics to obtain uniform irradiance with the aspherical lens. The theoretical results of both designs are reasonably good. # 1998 Optical Society of America OCIS codes: 140.3300, 220.4830, 120.2440, 220.0220.