While the alignment and rotation of microparticles in optical traps have received increased attention recently, one of the earliest examples has been almost totally neglected--the alignment of particles relative to the beam axis, as opposed to about the beam axis. However, since the alignment torques determine how particles align in a trap, they are directly relevant to practical applications. ...

James R. Fienup used phase retrieval algorithms to determine the aberrations in the Hubble Space Telescope. The theory of phase retrieval is described in this paper. Other applications of phase retrieval, such as undersampled broadband images, lensless coherent imaging, and optical metrology, are also discussed. Introduction: James R. Fienup established the use of phase retrieval in the early 1...

Highly sensitive photoalignment of liquid crystals (LCs) can be realized by axis-selective triplet energy transfer. Addition of a triplet photosensitizer (phosphorescent donor) into a photocrosslinkable polymer tethering E-cinnamate side chains ensures dramatic enhancement of photosensitivity to generate the optical anisotropy of polymer film and surface-assisted LC photoalignment. Photoirradia...

This paper presents a new approach towards the problem of recursive optical flow estimation from image sequences based on the differential framework proposed by Horn & Schunck. We show that gain is achieved both from computational and accuracy points of view when treating the estimation task recursively. Incorporation of the temporal axis into the estimation process is done by combining a tempo...

Electronic structures and optical excitations in Möbius conjugated polymers are studied theoretically. Periodic and Möbius boundary conditions are applied to the tight binding model of poly(para-phenylene), taking exciton effects into account. We discuss that oligomers with a few structural units are more effective than polymers for observations of effects of discrete wave numbers that are shif...