Beam shaping design for coupling high power diode laser stack to fiber

Abstract

A beam shaping technique that rearranges the beam for improving the beam symmetry and power density of a ten-bar high power diode laser stack is simulated considering a stripe mirror plate and a V-Stack mirror in the beam shaping system. In this technique, the beam of a high power diode laser stack is effectively coupled into a standard 550 μm core diameter and a NA=0.22 fiber. By this technique, compactness, higher efficiency, and lower cost production of the diode are possible.

High brightness beam shaping and fiber coupling of laser-diode bars

“…where BPP total is the BPP of the laser beam in a diagonal direction and d fiber and NA denote the diameter and numerical aperture of the fiber, respectively [5][6][7][8][9]. Based on the BPP of single mini-bar after beam shaping, we can arrange two minibars in the y direction and four mini-bars in the x direction, as shown in Eq.…”

“…More than 400 W of output power can be achieved based on 70% optical-optical efficiency, and equalizing brightness is 71.5 MW∕cm 2 · sr. The brightness of the proposed laser-diode system is 7 fold that of the widely used fiber laser pumping laser-diode modular (200 μm core diameter and NA 0.22 fiber, 500 W) [5].…”

“…For a typical laser-diode bar in the fast axis, the emitter size is about 1 μm with a divergence angle of 60°-90°(1∕e 2 , full angle), and the beam quality is close to the diffraction limit. In the slow axis, a laser-diode bar has a broad light-emitting area with a divergence angle of 6°-12°(1∕e 2 , full angle) [1][2][3][4][5]. There are also lightless areas between each emitter, and the beam quality is larger than the 100-fold diffraction limit.…”

Beam-shaping design for multi-wavelength diode laser stack system coupled into optical fiber for biomedical applications

“…When a larger amount of optical power is required, multiple diode laser bars can be arranged vertically to form a diode laser stack. The diode laser stacks are typically fabricated with pitches of about 1.8 mm between the bars (Ghasemi et al, 2011), although they can be larger (Injeyan and Goodno, 2011) to allow attachment of the FAC microlens directly to the mini-channel heat sink via a glass submount. However, the high astigmatism exhibited by these laser sources in the far field (Diehl, 2000) implies the need to use an optimized beam shaping system to rearrange the light beam and reach efficient fiber coupling.…”

Фотоотверждаемая Полимерная Композиция На Основе Термостойкого Ароматического Полиамида Для Формирования Оптических Элементов Методом Двухфотонной Полимеризации

“…Разработка новых оптических приборов, появление мощных лазерных источников требуют создания сложных оптических систем с асферическими поверхностями, которые затруднительно произвести традиционными способами. Например, коллимация и фокусировка мощных лазеров и лазерных диодов со сложным модовым составом требует применения дорогих пространственных модуляторов света [1] и сложных оптических систем [2,3]. Решением такой задачи может стать создание асферических оптических элементов, в том числе микронного масштаба [4] по специально рассчитанной компьютерной модели [5,6].…”