Abstract: Described are an optical transmitter and a method for generating a single sideband optical signal. The method includes generating a data signal at a first power level and at a second power level with a predetermined ratio being defined between the power levels. The data signal at the first power level is applied to a phase module disposed in a laser cavity of a semiconductor laser to generate a frequency modulated laser signal having a double sideband. The intensity of the frequency modulated laser signal is modulated in response to the data signal at the second power level to yield the single sideband optical signal. Optical transmitters implementing the method have an increased manufacturing yield and reliability, a lower fabrication cost and a decreased size compared to other optical single sideband optical transmitters.

Abstract: A system for producing laser output from a solid-state laser is described. The laser output comprises two orthogonally polarized axial modes of light at different frequencies having linear polarization. In one embodiment, the two modes are at different frequencies and can be merged together to produce energy waves of variable frequency. This device has applications in microwave generation and velocity measurements.

Abstract: An optical frequency discriminator having enhanced linearity is provided, which discriminator may be utilized in FM communications systems or in other applications. The discriminator has two interferometers with the optical path length difference for the first interferometer being .DELTA.L and for the second interferometer being m.DELTA.L where m>1. The optical FM signal is applied in parallel to both optical interferometers with approximately m.sup.3 times as much of the signal being applied to the first interferometer as to the second interferometer. Each interferometer has an output signal versus frequency characteristic with a substantially linear region about a center frequency, which center frequency is approximately equal to the center frequency of the input optical signal.

Abstract: This invention relates to a tunable solid-state laser which generates ultrashort output pulses with continuous wave pumping. The device includes a lasing medium having a gain cross section of 10.sup.-18 cm.sup.2 or less and mode beating characteristics, which lasing medium is mounted in a laser cavity. A continuous wave pumping beam is applied to the lasing medium causing an output, a portion of which is applied to an intensity dependent nonlinear cavity. The output applied to the nonlinear cavity is retroreflected back through the cavity and is interferometrically combined with the laser output. The relative lengths of the cavities are initially selected such that phase changes caused by the nonlinear medium result in substantially maximum enhancement of intensity peaks of the laser output, causing self starting of pulsed operation.

Abstract: A method of manufacturing a Faraday isolator which is wavelength-independent over an extended predetermined range of wavelengths and provides high isolation over the extended wavelength range.