We introduce the feature issue on the Optics in the Life Sciences Congress held on April 2-5, 2017 in San Diego, CA. The Congress consisted of 5 topical symposia: (i) Bio-optics Design and Application; (ii) Novel Techniques in Microscopy; (iii) Optical Molecular Probes, Imaging and Drug Delivery; (iv) Optical Trapping Applications; and (v) Optics and the Brain. These separate symposia also held joint sessions of common interest. The following highlights some of the topics from the Congress.

Optical tweezers are tools made of light that enable contactless pushing, trapping, and manipulation of objects, ranging from atoms to space light sails. Since the pioneering work by Arthur Ashkin in the 1970s, optical tweezers have evolved into sophisticated instruments and have been employed in a broad range of applications in the life sciences, physics, and engineering. These include accurate force and torque measurement at the femtonewton level, microrheology of complex fluids, single micro- and nano-particle spectroscopy, single-cell analysis, and statistical-physics experiments. This roadmap provides insights into current investigations involving optical forces and optical tweezers from their theoretical foundations to designs and setups. It also offers perspectives for applications to a wide range of research fields, from biophysics to space exploration.