980 nm high brightness external cavity broad area diode laser bar

Spectral beam combining of a 980 nm tapered diode laser bar

“…Jechow et al [7], has used an external cavity in an off-axis arrangement for spectral beam combining of a broad area laser bar and achieved a beam with M 2 slow < 14 and M 2 fast < 3 at an optical power in excess of 10 W. Moreover, Jensen et al [8], has used off-axis spectral beam combining on a segmented broad area diode laser and achieved an improvement in the beam quality of a factor of 3.4 compared to that of a freely running single emitter on the array. Recently, Vijayakumar et al [9], applied this technique on a 12 element broad area diode laser bar and achieved an improvement in beam quality of a factor of 5-6 to that of a free running emitter on the same bar.…”

Development of Spectral Beam Combining of Diode Laser by Grating and External Cavity

“…Schematic of SBC with external cavity feedback based on grating 由图 1 可见， 光谱合束装置是由半导体激光器阵列(DLA)、 快轴准直镜(FAC)、 慢轴准直镜(SAC)变换柱 透镜、 光栅与外腔镜组成。半导体激光器的大发散角， 会严重限制了半导体激光器阵列和叠阵的光谱合束， 原因在于慢轴光束的发散， 使得每个阵列单元之间形成交叉耦合， 这种交叉耦合导致多旁瓣输出 [10] [12] 国波茨坦大学和丹麦技术大学提出了一种基于离轴反馈的光谱合束方法 [16][17] 2009 年丹麦技术大学 Vijayakumar [18] 等利用图 7(a)所示的旁轴反馈对高功率宽发射面半导体激光器线…”

Fast-to-slow axis mode imaging for brightness enhancement of a broad-area laser diode array

“…Using these external cavity techniques, the output from individual emitters within a BAL array can be spatially combined to produce a single output beam with increased total spatial radiance or brightness (power per square area per solid angle) [17]. Brightnesses as high as 79 MW·cm −2 ·sr −1 [18] have now been demonstrated at 980 nm from a BAL array in an external cavity. While demonstrated external cavity techniques can improve BAL beam quality, the cavities are relatively complex and have limited usable current ranges or limited potential for beam combing.…”