Baselworld PMW

PERFORMANCE
The Citizen Cal.0100 Eco-Drive operates as a completely autonomous movement that is able to achieve its annual ±1 second accuracy without the need for external connections to digital references. While many will remember Eco-Drive as one of Citizen's more recent innovations, Citizen has been working towards completely isolated and accurate quartz movements since as early as 1975 with the introduction of the Citizen Crystron Mega, which was capable of reaching accuracy levels of ±3 seconds annually thanks to an operating frequency of 4.19MHz. With a strict philosophy of improving upon past innovations, Citizen designed the Cal.0100 to operate at a frequency of 8.4MHz (8,388,608Hz), which, when combined with a newly-engineered AT-cut quartz crystal oscillator, achieves unprecedented accuracy in their lineage of Eco-Drive movements.

AT-CUT QUARTZ CRYSTAL OSCILLATOR
While AT-cut quartz crystals have indeed been in production and use since as early as 1934, the technology is more common in larger applications and not necessarily wristwatches. To address the needs of individuals seeking only the most accurate performance in a wristwatch, Citizen sought to apply and optimize this available technology in a way that could serve watch consumers on a more direct and personal level. When working to reach the accuracy of the Cal.0100, Citizen opted for an AT-cut quartz oscillator instead of a more traditional tuning fork shape (XY cut). Perhaps most notably, AT-cut variations allow for greater temperature tolerances, specifically in the range of -40°C to +125°C. Additionally, this configuration allows for reduced deviations caused by wearer orientation, which can cause significant changes in accuracy that aren't negligible when attempting this kind of performance. As a result, wearers will not have to worry about errors caused by spatial orientation and positioning becomes less of a concern. The same can be said about durability, which Citizen also improved upon in conjunction with the AT-cut oscillator. After all, shock experienced in day-to-day situations could easily prove detrimental even for quartz movements. And when the goal is an annual accuracy of ±1 second, that just isn't acceptable.

DURABILITY
Aside from temperature and gravitational variables, Citizen also accounted for the way shock could affect the accuracy of the Cal.0100. This is addressed by Citizen's proprietary Shock Counteraction Function, which locks the rotor before restarting the movement after significant shock and on-board automatic hand correction that constantly checks positioning. After detecting shock or any kind of deviation, this function corrects hand positioning so that it remains in line with the movement's precise display of time. These functions combined with the higher operating frequency, AT-cut crystal oscillator, and temperature correction features inevitably require a greater degree of power consumption. Understandable, since this is a movement that operates at a frequency 256 times higher than a standard quartz movement. Thus, Citizen was able to tweak, improve, and combine a range of their own proprietary technologies to achieve the accuracy and autonomy of the Cal.0100. No GPS connection, no radio signals, just the purest to-the-second expression of time in the most accurate form of Eco-Drive to date.