Patent ID: 9348317
Filing Date: 2016-05-24
CPC Classification: G04D

Claim Text:
1. A method of measuring accuracy of at least one timepiece that is a mechanical watch, including at least one visual display device, and where one of said at least one visual display device of said timepiece is selected as an experimental display, the method comprising:—a first measured instant, at which said experimental display is in a first display position corresponding to a first image generated by an image generator coupled to an internal or external time reference source, said first image being supplied at a request of a user, is stored with said corresponding internal or external time reference source, said first display position is synchronized, in optical comparison to a time display position of said timepiece with said first image, the user alters the position of said first image as desired to synchronize said first image with a real timepiece display, a first display value, corresponding to said first image, is determined and said first display value is stored in a storage device in correlation with said first instant;—after a determined time interval following said first instant, a second measured instant, at which said experimental display is in a second display position corresponding to a second image, said second image being generated by said same image generator, said second image being supplied at the request of the user, is stored with said corresponding time reference source said second display position is synchronized, in optical comparison to the time display position of said timepiece with said second image, the user alters the position of said second image as desired to synchronize said second image with said real timepiece display a second display value, corresponding to said second image, is determined and said second display value is stored in said storage device in correlation with said second instant;—a time difference displayed between said second display value and said first display value is calculated; and—a variation in rate of said experimental display is calculated, and said variation in rate is displayed on a viewing device.