Fiber Coupled Diode Laser are widely used in various fields, such as small size, good beam quality, long life and stable performance. They are mainly used as the source of fiber lasers and solid-state lasers. They can also be used directly in laser medical, Materials such as cladding, welding and other fields. Due to the influence of fiber lasers in the development trend of high power, semiconductor lasers are also developing high power and high brightness. High-brightness semiconductor lasers have high optical power density, and the beam bundle is also ideal for high power fiber lasers Pump source. At present, the fiber-coupled semiconductor laser structure is mainly composed of single-tube coupling lasers, multi-tube coupling lasers, mini bar and bar / stack series. The multi-tube coupling lasers become the mainstream pump source of fiber lasers because of their high reliability First, this paper mainly introduces the technology and realization of realizing high-brightness semiconductor lasers by multi-tube fiber coupling technology.
Multi-tube structure is the separation of the semiconductor laser beam emitted by shaping, rearranged, combined after coupling into a single fiber, which can improve the laser output power. Since the discrete semiconductor laser chip must be mounted on a heat sink with a certain size,Fiber Coupled Diode Laser if the output beams of the plurality of semiconductor lasers are arranged and focusedly coupled directly, the combined beam volume is usually limited due to the limitation of the volume of each chip and its heat sink Large, it is difficult to obtain small core high brightness fiber coupling output. In order to reduce the size of the space of the combined beam, we must take certain measures. To this end, Kaipu Lin independent research and development of multi-tube coupling structure using ladder heat sink, focusing lens, coupled fiber and a unique installation, optical design simplifies the complexity of the structure,Fiber Coupled Diode Laser reducing the size of the components, greatly improving the semiconductor The output power of the laser, while ensuring a reasonable operating temperature of the coupling point.
In the multi-tube coupling before the discrete semiconductor laser chip for aging screening, thus ensuring the reliability of multi-tube coupling. Single tube random failure characteristics of independent, compared to Bar, no thermal effect of interference, the replacement of a single tube also increased its durability, with a high cost advantage.
3 fiber coupling
In order to achieve high brightness, high power output can increase the number of simultaneous single-tube semiconductor lasers to ensure a higher output power, but the beam after the beam coupling into a single fiber must also meet the three conditions: (BPP, the product of the beam waist radius and the radius of the divergence angle) is smaller than that of the laser beam. The second is that the beam diameter of the beam is smaller than that of the fiber. Fiber beam parameter product. which is
However, in practical applications, only the square area of the fiber center is the available region for the core with a core diameter of 200 μm and a numerical aperture of 0.22, with a BPP value of 22 mm mad. The maximum BPP of the coupled semiconductor laser beam is: 9xxnm semiconductor The laser beam data output from the single chip of the laser is taken as an example. The diameter of the slow axis is 95μm and the divergence angle is 10 ° (99% of the energy). The beam parameter is about 8.3mm mrad; Divergence angle of 39 ° (99%), the beam parameters of about 0.51mm mrad. By software simulation, theoretically 200μm / 0.22NA fiber can be coupled to 28 laser beam. At present, after years of technology accumulation, Kaipu Lin 9xxnm high-brightness Fiber Coupled Diode Laser maximum coupling discrete semiconductor lasers up to 20.
In this paper, a multi-tube coupling structure and a high-brightness laser output method are introduced. In the field of high-brightness semiconductor lasers,Fiber Coupled Diode Laser multi-tube fiber coupling technology is widely used in wavelength-emitting lasers such as 9xxnm, 793nm and 808nm, Lasers and thulium-doped fiber lasers and neodymium-doped solid-state lasers; 10W-200W different power levels can correspond to a variety of operating modes and power requirements of fiber laser applications. In the future, Kaiping will achieve higher brightness Fiber Coupled Diode Laser by increasing the polarization beam, multi-wavelength beam and so on, providing more products and services for high power fiber laser users.