<title>Optically-addressed spatial light modulator composed of organic photochromic thin film: its high durability and stable data retention</title>

Abstract

A highly durable and stable OASLM (Optically-Addressed Spatial Light Modulator) was fabricated with a diarylethene derivative by heating and pressing a dye-dispersed polymer between two flat glass plates in a vacuum. It can be colored and bleached effectively by the visible light irradiation in the ranges of wavelength 400-440nm and 500-600nm, respectively. As a result of the characterization, it was confirmed that this device is durable against 10,000 times iteration of coloring/bleaching and the isomerization state was stably retained in the dark for more than 3months. Since the difference in refractive index between the dye-dispersed polymer and the glass plates is sufficiently small, diffraction at the photochromic layer brought about in the light irradiation can be suppressed. Additionally to small thickness of the photochromic layer (2mm), this will be an important advantage in realizing the high data resolution. Due to the excellent durability and stability, its practical application is expected in the field of data processing requiring both the long-term accumulation of experience and the high-speed parallel operation (i.e. pattern recognition, machine vision and real-time control of robots). Further, this device can readily comply with the multi-device system due to disk layout or cartridge design since the device requires no power supply and its structure is quite simple.