received by the International Bureau on 18 May 2020 (18.05.2020)

1. A system (100, 200, 300, 500, 600, 800) comprising at least one decorative element (104, 224, 304, 344, 802) mechanically and moveably attached in a liquid (106, 206, 306, 506, 606, 830) on a displacement mechanism (110, 112, 114, 116, 316, 326, 510, 514, 516, 610, 614, 616, 804, 806, 820, 822), wherein the displacement mechanism is made of an articulated chain (116, 316, 516), the liquid sharing a substantially similar refraction index as at least a portion of the displacement mechanism so that at least a portion of the displacement mechanism is substantially invisible to an observer.

2. The system of claim 1, wherein the displacement mechanism is made of an articulated chain (116, 316, 516) of rigid elements (102, 104, 302, 304, 502) actuated by a transmission (114, 124, 326, 514), wherein at least one of the rigid elements is made of a material having a refraction index substantially identical to the refraction index of the surrounding liquid (106, 206, 306, 506) so as to be essentially invisible to an observer.

3. The system of claim 1, wherein the displacement mechanism is made of rigid areas and flexible areas actuated by a transmission (614), wherein at least a part of the semi-flexible element is made of a material having a refraction index substantially identical to the refraction index of the surrounding liquid (606) so as to be essentially invisible to an observer.

4. The system of claim 1, wherein the displacement mechanism is made of a flexible element (806) actuated by a transmission (820, 822), wherein the flexible element is made of a material having a refraction index substantially identical to the refraction index of the surrounding liquid so as to be essentially invisible to an observer.

5. The system of claims 1 , 2, 3 or 4, wherein visible portions of the displacement mechanism follow a predefined path and participate to the generation of a changing image.

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6. The system of clai s 1, 2, 3, 4, or 5, wherein a transmission (114, 124, 326, 514, 614, 820, 822) connected to the displacement mechanism (110, 112, 114, 116, 316, 326, 510, 514, 516, 610, 614, 616, 804, 806, 820, 822) is actuated by the user.

7. The system of claims 1, 2, 3, 4 or 5, wherein a transmission (114, 124, 326, 514, 614, 820, 822) connected to the displacement mechanism (110, 112, 114, 116, 316, 326, 510, 514, 516, 610, 614, 616, 804, 806, 820, 822) is actuated by an automatic actuation mechanism (134).

8. The system of claims 6 or 7, wherein the movement of the at least one decorative element (104, 224, 304, 344, 802) generates an animation.

9. The system of claims 7, wherein the movement of the at least one decorative element (104, 224, 304, 344, 802) indicates a value.

10. The system of claim 7, wherein the automatic actuation mechanism (134) is a timepiece.

11. The system of claim 10, wherein the movement of the at least one decorative element (104, 224, 304, 344, 802) indicates time.

12. The system of claim 11, wherein the movement of the at least one decorative element (104, 224, 304, 344, 802) along adjacent indices (226) indicates time.

13. The system of claims 2, 3, 4, 5 or 8, wherein the transmission (114, 124, 326, 514, 614, 820, 822) is actuated by a mass reacting to the changes of orientation of the system relative to gravity.

14. The system of claim 13, wherein the movement of the at least one decorative element (104, 224, 304, 344, 802) generates an animation.

15. A method for animating a decorative element (104, 224, 304, 344, 802), using the system of any of the preceeding claims, the method comprising at least the steps of: a. attaching the system to the user’s clothing or around an appendage of the user’s body; b. moving the portion of the body to which the system is attached; and

c. observing the animation effect.

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16. The system of claim 1, further including a thermal compensation system, the system comprising a mechanism accommodating thermal expansion and/or contraction of the liquid, avoiding the generation of unacceptably high pressure which could result in liquid leaking out of the system in case of temperature rise, or the generation of unattractive gas bubbles in the liquid in case of low temperature.

17. A portable/wearable device comprising a system according any of the preceding claims.

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