A monolithically integrated glass microlens optical scanner is presented. A new wafer-level fabrication approach addresses the issue of microlens integration and alignment in conventional microlens integrated devices. A through-silicon plano-convex glass microlens has been fabricated on a silicon substrate prior to the formation of an integrated microlens actuator, realized through two thermal reflow processes at 850 °C. A lateral comb drive is adapted to demonstrate the glass microlens scanner. The 800 µm diameter microlens was laterally shifted up to ±51.6 µm when an ac voltage of 28.5 V in amplitude was applied at a resonant frequency of 1.749 kHz at atmospheric pressure. The optical scanning angle of ±2.0° has been obtained with the fabricated device.

A miniaturized two-dimensional forward optical scanner with a monolithically integrated glass microlens was developed for microendoscopic imaging applications. The fabricated device measures 2.26 × 1.97 × 0.62 mm3 in size and a through-silicon microlens with a diameter of 400 µm and numerical aperture of 0.37 has been successfully integrated within the silicon layer. An XY stage structure with lens shuttle and comb actuators was designed, and proprietary glass isolation blocks were utilized in mechanical and electric isolation of X- and Y-axis actuators. Resonant frequencies of the stage in X and Y directions were 3.238 and 2.198 kHz and quality factors were 168 and 69.1, respectively, at atmospheric pressure. Optical scanning test has been performed and scan angles of ±4.7° and ±4.9° were achieved for X and Y directions, respectively.