Abstract: An embodiment of the inventive concept provides a physics module of a chip-scale atomic clock. The physics module includes: a housing; a laser source disposed in the housing and generating a laser beam; a vapor cell disposed above the laser source to generate a transmitted beam from the laser beam; and a detector disposed above the vapor cell to detect the transmitted beam. Here, the vapor cell may include a plurality of optical patterns configured to polarize the laser beam.

Abstract: An embodiment of the inventive concept provides a physics module of a chip-scale atomic clock. The physics module includes: a housing; a laser source disposed in the housing and generating a laser beam; a vapor cell disposed above the laser source to generate a transmitted beam from the laser beam; and a detector disposed above the vapor cell to detect the transmitted beam. Here, the vapor cell may include a plurality of optical patterns configured to polarize the laser beam.

Abstract: In the present invention, time information is sent through a common power line in executing home automation devices or using various industrial equipments. In the power line broadcasting, a small amount of data, such as time information, is transmitted unidirectionally, and long-distance power line broadcasting can be possible using carriers of a low frequency band. time setting for various instruments is automatically performed in response to a power signal after a breakdown of electric current, making unnecessary a user's action to perform the time setting, and the existing power line can be used without change.

Abstract: In the present invention, time information is sent through a common power line in executing home automation devices or using various industrial equipments. In the power line broadcasting, a small amount of data, such as time information, is transmitted unidirectionally, and long-distance power line broadcasting can be possible using carriers of a low frequency band. time setting for various instruments is automatically performed in response to a power signal after a breakdown of electric current, making unnecessary a user's action to perform the time setting, and the existing power line can be used without change.

Abstract: The present invention relates to an optical frequency synthesizer and an optical frequency synthesizing method using femtosecond laser optical injection locking, which inject a femtosecond laser optical frequency comb into a diode laser, thus obtaining single-mode laser light, phase-locked to only a single mode in the optical frequency comb, and which change the optical frequency and interval, that is, the repetition rate, of a femtosecond laser, together with the frequency of a semiconductor laser, thus scanning optical frequencies while realizing a single desired optical frequency. The optical frequency synthesizer using femtosecond laser optical injection locking, includes a mode-locked femtosecond laser (110), which is a master laser, and a diode laser (120), which is a slave laser and into which laser light emitted from the femtosecond laser is injected.

Abstract: The present invention relates to an optical frequency synthesizer and an optical frequency synthesizing method using femtosecond laser optical injection locking, which inject a femtosecond laser optical frequency comb into a diode laser, thus obtaining single-mode laser light, phase-locked to only a single mode in the optical frequency comb, and which change the optical frequency and interval, that is, the repetition rate, of a femtosecond laser, together with the frequency of a semiconductor laser, thus scanning optical frequencies while realizing a single desired optical frequency. The optical frequency synthesizer using femtosecond laser optical injection locking, includes a mode-locked femtosecond laser (110), which is a master laser, and a diode laser (120), which is a slave laser and into which laser light emitted from the femtosecond laser is injected.