Piezo-actuated adaptive prisms for continuously adjustable bi-axial scanning

Abstract

We present two piezo-actuated adaptive prisms with apertures of 8 mm based on a bi-axial continuously tiltable glass window on top of an optical fluid, enabling fast scanning applications in a compact, linear axial design. One prism with a device size of 58 by 51 mm is optimized for scan angles of ±6.4 • and response times of 2.5 ms. A second compact prism uses spiral-shaped actuators to achieve a reduced device diameter of 33 mm at slightly compromised maximum scan angles of ±4.0 • with response times of approximately 4 ms. We show the design and FEM-based optimization of the prisms, their fabrication and the characterization of the scan angles and of the dynamic behavior. Finally, we also demonstrate the linearity of the system and discuss a simple control model.

MR-compatible optical microscope for in-situ dual-mode MR-optical microscopy

“…Fluorescence microscopy with excitation in the visual range or phase contrast microscopy can be performed without structural modifications; the use of vastly different wavelengths or illumination powers such as two-photon fluorescence microscopy might require some changes in the optical materials or in the light source which is safely located outside of the scanner. Scanning methods such as confocal microscopy or optical coherence tomography could be performed by integrating compact, non-magnetic piezo-actuated adaptive prisms [43,44], while the adaptive lens can also be used for fast axial scanning [45] and for aberration correction [46].…”

3D-scanning microscopy with adaptive lenses and prisms for zebrafish studies

“…As the wavefront tilt is induced by the adjustment of the controlled path-length caused by the refractive index transition from the fluid in the prism to air (approximately 1.48 to 1), a surface tilt of 1 deg is required to induce a wavefront tilt of 0.48 deg. It has been verified that the prism is capable to induce wavefront tilts up to AE6.4 deg and achieves response times of 2.5 ms. 27 Fig. 1 (a) Schematic of the axial scanning setup with an adaptive lens.…”

“…[24][25][26] However, the scanning angle range of electrowetting-based prisms is too narrow to achieve a large field of view. Recently, we introduced a piezo-actuated adaptive prism with a large tuning range 27,28 as a suitable alternative to galvanometer mirror that enables an in-line transmissive configuration with large scanning angle range.…”

Self-Sensing of a Magnetically Actuated Prism

“…However, they have the disadvantage that they fold the beam path, resulting in a bulkier setup and requiring a precise alignment as each mirror doubles the alignment error. To avoid this issue, we have developed piezo electrically [ 1 ] and magnetically [ 2 ] actuated transmissive prisms for bi-axial beam steering and have already successfully used them in a microscope setup [ 3 ].…”