The present invention discloses a device and method for controlling a lasing wavelength of a tunable laser, and a wavelength division multiplexed-passive optical network having the same. The device may display a first set of images and receive a user input. The pointers are saved to persistent storage at the earlier time. In this way, the thickness of the blade main body can be reduced while ensuring the performance of the gas turbine engine, thereby contributing to a reduction in weight. Damping systems to provide smooth operation and movement of the weight and the aerostabilizers are also offered.