摘要:
A laser module includes a semiconductor laser element and a feedback optical component forming an external cavity with the semiconductor laser element. Even if a ratio of a current threshold of the laser module changing according to a polarized state of returned light from the feedback optical component to a current threshold of the semiconductor laser element is in an arbitrary range within a predetermined range, a total value of a relative intensity noise occurring between a first frequency determined according to a cavity length of the external cavity and at least equal to or more than a frequency band of using a laser light and a second frequency calculated by multiplying the first frequency by a predetermined number is equal to or more than −40 dB.
摘要:
A package accommodates an LD device for emitting laser light with the center wavelength of which is in a range of 1300 to 1440 nm and airtight seals a light path extending from the LD device to an incident end of an optical fiber. The package is filled with a nitrogen gas at a standard atmospheric pressure with the amount of moisture limited to a value lower than 100000 ppm by volume or less. Therefore, the amount of moisture in the light path for laser light within the package is limited to 100000 ppm by volume or less.
摘要:
A laser module includes a semiconductor laser element and a feedback optical component forming an external cavity with the semiconductor laser element. Even if a ratio of a current threshold of the laser module changing according to a polarized state of returned light from the feedback optical component to a current threshold of the semiconductor laser element is in an arbitrary range within a predetermined range, a total value of a relative intensity noise occurring between a first frequency determined according to a cavity length of the external cavity and at least equal to or more than a frequency band of using a laser light and a second frequency calculated by multiplying the first frequency by a predetermined number is equal to or more than −40 dB.