Magneto-optical spatial light modulator driven by current-induced domain wall motion for holographic display applications.

We have developed a magneto-optical spatial light modulator (MO-SLM) with a 10 k × 5 k pixel layout and with a pixel pitch horizontally of 1 µm and vertically of 4 µm. An MO-SLM device pixel has a magnetic nanowire made of Gd-Fe magneto-optical material whose magnetization was reversed by current-induced magnetic domain wall motion. We successfully demonstrated the reconstruction of holographic images, showing large viewing zone angles as wide as 30 degrees and visualizing different depths of the objects. These characteristics are unique to holographic images, providing physiological depth cues which may play a vital role in three-dimensional (3D) perception.

Image quality assessment procedure for holographic displays based on exact numerical reconstruction of computer-generated holograms.

We proposed a technique for the computer-based reconstruction of computer-generated holograms and evaluation of the reconstructed 3D image quality. The proposed method mimics how the eye's lens works, thus allowing for viewing position and eye focus adjustments. The angular resolution of the eye was used to output reconstructed images with the requisite resolution, and a reference object was used to normalize the images. Such data processing enables the numerical analysis of image quality. By comparing the reconstructed images with the original image with incoherent illumination, the image quality was quantitatively evaluated.