Abstract: Optical devices and methods of manufacture are presented in which a multi-tier connector is utilized to transmit and receive optical signals to and from an optical device. In embodiments a multi-tier connection unit receives optical signals from outside of an optical device, wherein the optical signals are originally in multiple levels. The multi-tier connection unit then routes the optical signals into a single level of optical components.

Abstract: An in vitro training method for training genioglossus muscle strength includes adhering an electrode patch of an in vitro training device to a bottom of a chin of a user during a non-sleep period. The electrode patch receives an electrical stimulation signal from an electrical stimulation module of the in vitro training device to stimulate the genioglossus muscle of the user through transdermal electrical stimulation. The electrode patch includes a body surface adhering face and an assembling face opposite to the body surface adhering face. The body surface adhering face is adhered to the bottom of the chin of the user to align with the genioglossus muscle. The electrical stimulation module is disposed on the assembling face and in electrical connection with the electrode patch. The electrical stimulation module sends an electrical stimulation signal to stimulate the genioglossus muscle through transdermal electrical stimulation.

Abstract: An in vitro training method includes scanning a user's oral cavity to create a first oral cavity model. An articulator body is selected according to the first oral cavity model, and plural first customized electrode sheets are formed and assembled onto the articulator body to obtain an in vitro training device. The user bites the in vitro training device during a non-sleep period and uses the plural first customized electrode sheets to proceed with electrical stimulation on a top surface and two sides of a tongue of the user, thereby training a muscular endurance of infrahyoid muscles of the user for a training period. The user's oral cavity is scanned again to create a second oral cavity model. The first oral cavity model is compared with the second oral cavity model to timely renew the customized electrode sheets when the image over rate is lower than 80%.

Abstract: A communication device and method for downloading navigation maps include creating a database to store navigation maps, and acquiring position information of a location of the communication device. The communication device and method further include downloading a navigation map including the position information from a server if the database does not have stored navigation map including the position information, and storing the downloaded navigation map into the database.