"Eco-driven Photokinetic Energy" is a registered trademark of Citizen. Photokinetic watch can absorb any visible light source and convert it into kinetic energy to drive the watch to run. Photodynamic watches do not use ordinary quartz watch batteries, which avoids the pollution of waste batteries to the environment and does not need to replace batteries regularly, bringing convenience to the wearer. The power-saving function of the optical kinetic watch ensures that the watch can run normally in the dark for several months to ten years when it is fully charged, depending on the model of the movement.

Photokinetic energy is the core technology of Citizen. Since the first optical dynamic watch came out in 1995, Citizen Company has continuously improved the design and technology of optical dynamic watches, overcome various technical problems such as light absorption, energy storage and power saving of dial, and finally realized the perfect integration of cutting-edge watchmaking technology, exquisite and fashionable design and optical dynamic movement.

The dial design of Citizen watch is very beautiful, but the color will affect the absorption of light, and various complex functions are added, such as perpetual calendar, minute repeater, stopwatch and so on. , all involve specialized research on how to allocate the stored power reasonably, such as LED display screen, which needs to consume a lot of power. "Integration of technology and beauty" is the product research and development purpose that Citizen always adheres to. For optical dynamic watches, to achieve exquisite appearance and technical realization, technical departments and design departments need to work together to develop perfect products.