Micromachined scanning confocal optical microscope.

We have constructed a miniature confocal optical microscope for monochromatic imaging that uses single-mode fiber illumination and a two-phase off-axis zone plate objective lens. The scanning mechanism consists of two micromachined silicon torsional scanning mirrors with orthogonal axes of rotation. The objective lens is made of fused silica and has a N.A. of 0.24 at lambda = 0.6328 microm, with a 1.0-mm working distance. The device is side looking, with die dimensions of 1.2 mm x 2.5 mm x 6.5 mm. We have measured 1.0-microm resolution over a 100-microm field of view.