As a system, which put the optical neuro-computing into practice, a novel architecture based on organic photochromism was described, The performance of the system was examined concretely by means of computer simulation. Based on the result, a prototype system was constructed using a bulk amorphous thin film of diarylethene to prove the feasibility of the architecture. Using the prototype, preliminary experiment was carried out to confirm the function of optical data inscription and parallel analog operation. New concept of data processing device was also suggested from the discussion over the characteristics of the system.