4 results about "Longitudinal mode" patented technology

A laser light source comprises a semiconductor laser adapted for pulsed operation, a partially transmitting wavelength selective light reflector. The semiconductor laser comprises a front facet and a back facet. The front facet and the back facet define an internal laser cavity. The internal laser cavity comprises a laser active medium. The partially transmitting wavelength selective light reflector has a peak reflectivity within a gain bandwidth of said laser active medium. The wavelength selective light reflector and the back facet define an external laser cavity. A roundtrip time of light in the external laser cavity is about 20 nanoseconds or less. A full width half maximum bandwidth of the wavelength selective light reflector is adapted to accommodate at least 12 longitudinal modes of the internal laser cavity and at least 250 longitudinal modes of the external laser cavity.

The invention discloses an all-solid-state laser capable of obtaining single-frequency output at a wavelength of 558nm. The all-solid-state laser comprises a pumping source system and a Z type resonator device, wherein the pumping source system comprises a laser diode LD, an optical fiber and a focusing coupling lens system which are arranged on an optical path in sequence; the Z type resonator device comprises a rear mirror, a concave folding mirror, a yellow light output mirror and a total reflective mirror which are arranged in a Z type cavity in sequence; wave plates and a laser gain medium are arranged between the rear mirror and the concave folding mirror; a birefringent filter is arranged between the concave folding mirror and the yellow light output mirror; and a frequency doubling crystal is arranged between the yellow light output mirror and the total reflective mirror. According to the all-solid-state laser, the high power density of fundamental light in the cavity is fully utilized and the frequency doubling efficiency is improved by adopting the Z type cavity, so that the yellow light laser output at single longitudinal mode, low noise, high power and high energy is realized, and the defects of the laser in the prior art are successfully solved.

The invention discloses a device for perceiving oceanic turbulence and oceanic particles based on laser interference, relates to the technical field of optical simulation detection, and aims to solvethe problem that in the prior art, a single measurement system is unlikely to effectively separate a turbulence signal and a particle signal during simultaneous perception of the turbulence intensitychange and the particle concentration change. The device comprises a waterproof packaged shell, a first waterproof light-transmitting window, a second waterproof light-transmitting window, a continuous single longitudinal mode laser, a single mode optical fiber, a first optical fiber beam splitter, a second optical fiber beam splitter, a third optical fiber beam splitter, an optical fiber spatialoptical coupler, a filter, a polarizer, a spatial light optical fiber coupler, an optical fiber beam combiner, a first photoelectric detector, a second photoelectric detector, a third photoelectric detector, a signal power supply cable and a control analysis system. The device can effectively and simultaneously perceive the turbulence signal and the particle signal. The device can be widely applied to the field of oceanic exploration.