5 results about "Double-clad fiber" patented technology

An all-fiber inline optical tap adopts a configuration of a side-pump signal-and-pump combiner with a double-clad fiber (DCF) and one or more multimode fibers (MMFs). DCF comprises a first cladding and a coupling portion, whereas each of MMFs comprises a taper portion fused around the coupling portion. MMFs are configured to extract a part of combined optical energy and a part of an optical signal leaking in the first cladding of DCF with a sampled optical power proportional to a fiber laser power in a propagating direction. By pre-selecting a proper taper slope of the taper portion and an embedded depth the MMFs fused and embedded in the coupling portion, the all-fiber inline optical tap can be built with a customized ratio used in fiber laser power monitoring, diagnostics, and controls of a fiber laser system.

The application discloses a bladder cancer diagnosis and treatment integrated system and a control method thereof, which comprises a swept-frequency OCT light source, a treatment laser, a wavelength division multiplexer, a double-clad optical fiber, a flexible scanning probe, an endoscope imaging unit and an intelligent image processing and control terminal; imaging light and treatment laser are transmitted in a common light path by using the double-clad optical fiber, and scanning and light beam control are completed by means of a double-axis MEMS micro-mirror. The control method obtains tomographic structure information and depth information by reconstructing OCT data, and controls treatment laser power, galvanometer deflection and laser pause, recovery or stop by combining distance calculation, displacement compensation and blood perfusion monitoring, and is suitable for imaging navigation and closed-loop treatment in bladder cancer surgery.

The application relates to the field of high-power fiber lasers, and particularly discloses a femtosecond laser preparation method of a pump light recycling grating and a spectrum measuring device. The preparation method takes a double-clad fiber as a substrate, adopts femtosecond laser to be focused in the inner cladding through a coating layer, writes a fiber Bragg grating through a multi-layer line scanning technology, prepares a uniform grating or a chirped grating, and flexibly controls a grating modulation area by adjusting parameters. The spectrum measuring device is composed of an ASE broadband light source, a multimode fiber coupler, a multimode fiber matched with the inner cladding diameter and a double spectrometer, and realizes real-time and accurate measurement of the transmission and reflection spectrum of the inner cladding grating. The application solves the problems of low coupling efficiency, poor reliability and difficulty in reflecting specific wavelengths in the traditional pump light recycling technology, the prepared grating is uniform in modulation, the pump light reflection effect is good, residual pump light can be recycled efficiently, and the system efficiency and integration level of the high-power fiber laser are significantly improved.

This invention provides a 980nm fiber laser based on co-pumping by an oscillator and an amplifier, comprising a pump source, an oscillator, a filter element, and a second ytterbium-doped double-clad fiber. The oscillator includes a high-reflectivity fiber grating, a first ytterbium-doped double-clad fiber, and a low-reflectivity fiber grating. The high-reflectivity fiber grating and the low-reflectivity fiber grating together form a resonant cavity. The first ytterbium-doped double-clad fiber, located within the resonant cavity, receives the pump light and generates 980nm signal light through stimulated emission. By designing an optical path structure for co-pumping by the oscillator and amplifier, and utilizing the filter element to filter out 1030nm light while allowing residual pump light to enter the subsequent amplification stage, the unabsorbed residual pump energy in the oscillator is reused. This significantly simplifies the system size and reduces costs while solving the core problems of severe pump energy waste and low optical-to-optical conversion efficiency in existing technologies.

According to one aspect of the present disclosure for achieving the above-described object, a multimodal imaging catheter inserted into the body to acquire information of an internal body tissue for achieving the above-described object is disclosed. The multimodal imaging catheter may include an imaging core including a double clad fiber and a focusing device, the imaging core transfers light to the internal body tissue and collects information within the internal body tissue; and an imaging sheath including the imaging core therein to protect the imaging core from an external environment and to separate the internal body tissue and the imaging core during an imaging operation of the multimodal imaging catheter for the internal body tissue.