Designing resonators with large mode volume and high mode discrimination.

We present a new approach for the calculation of resonator mirror shapes based on a simulated annealing optimization algorithm. Compared with the possibilities of conventional resonators with spherical mirrors, the method presented permits a large mode volume of the stationary field distribution of the oscillating lowestloss mode and an increase in its loss discrimination against the remaining ensemble of other modes at the same time. We present results for circular symmetric graded-phase mirrors that yield a difference of 30% between the diffraction losses of the fundamental mode and of other evaluated higher modes.

Angstrom resolution optical profilometry for microscopic objects.

An instrument capable of recording the amplitude and phase of reflected light with a phase resolution of better than lambda/3000 and the lateral resolution of a confocal scanning microscope was built. The instrument is based on a commercial microscope body and uses the regular interference contrast optics. The modifications consisted of adding a coherent (heterodyne) detector and a confocal laser scanning system. Two-dimensional surface images of amplitude, slope, and profile were taken with a step height resolution of typically 0.5-2 A. The instrument is described, and its characteristics for surface profilometry are discussed.

Recording and reconstructing holograms in the spectrum of a white-light source.

A method of recording in-line holograms in the spectrum of a 100-W commercial projector bulb is presented. The same spectrum produced by a prism spectroscope can be used for reconstructing white-light-recorded as well as laser-light-recorded holograms.