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In this paper, geometric-phase lenses, which can not only correct wavefront aberrations but also magnify an aerial image, have been proposed for use in an aerial display system composed of a retroreflector array, an orthogonal-circular polarization grating, a right-angle prism, and a quarter-wave plate. The geometric-phase lenses were demonstrated both experimentally and computationally by arranging them in the aerial display configuration and observing aerial images. We also investigated the relationship between the magnification and the field of view of an aerial image, and it has been found that there is the trade-off relationship between them.

We have succeeded in forming a polarization grating whose polarization diffraction properties are extremely independent of the incident angle by using polymer liquid crystal exhibiting biaxial optical anisotropy. It is considered that the extension of the optical path length and the decrease in the effective amplitude of optical anisotropy due to oblique incidences are offset by the biaxial optical anisotropy and, as a result, the retardation is compensated. The properties of this developed device have been experimentally demonstrated and theoretically explained.

In this work, a polarization grating in Raman-Nath regime was fabricated by using a photoreactive polymer liquid crystal exhibiting biaxial optical anisotropy. And from the measured characteristics, it has been demonstrated that the flat incident angle dependences on diffraction efficiency and polarization ellipticity are obtained by introducing biaxial optical anisotropy.

We propose two types of wavefront aberration correction in geometric-phase lenses (GPLs). First, in situations in which the incident light on a GPL has a wavefront aberration represented by the Zernike polynomial, the wavefront aberration is eliminated by setting a phase distribution that cancels the phase distribution of the incident light to GPL. Second, the aberration that occurs when a light wave is obliquely incident on the GPL is compensated for by a correction method that incorporates an optimization design using a genetic algorithm. These methods have been demonstrated not only by theory but also by experiments using imaging systems in which the designed and fabricated GPLs are utilized. These wavefront aberration correction methods can be expected to overcome wavefront aberration caused by the arrangement of optical elements in an optical system and contribute to expanding the application range of GPLs.