在垂直腔面发射激光器(VCSEL)作为显示光源的应用中,为了获得高功率的偏振激光,研究了980nm大口径底发射VCSEL的偏振特性。通过刻蚀矩形台面和矩形出光口径,制备矩形VCSEL。在连续条件下,出光口径为550μm×300μm的底发射矩形VCSEL最大输出功率为660mW,微分电阻为0.09Ω。实验中,矩形VCSEL在工作电流下,同时存在稳定的水平偏振光和竖直偏振光,并且沿着矩形长边出射的水平偏振光一直占据主导地位。而圆形VCSEL在水平和竖直方向的激射情况几乎相同。水平偏振光的激射光谱相对于竖直偏振光出现蓝移,并且用对称三层波导模型解释了蓝移现象。研究了矩形VCSEL的正交偏振比与矩形口径长宽比的关系。实验结果表明,矩形柱结构能够有效地稳定VCSEL的偏振方向,使大口径器件激射高功率的偏振激光。 In the application of vertical cavity surface emitting laser (VCSEL) as a display light source, the polarization characteristics of a 980 nm large diameter bottom emitting VCSEL were studied in order to obtain a high power polarized laser. A rectangular VCSEL was prepared by etching a rectangular mesa and a rectangular light exit aperture. Under continuous conditions, the maximum output power of the bottom-emitting rectangular VCSEL with a light-emitting diameter of 550 μm × 300 μm is 660 mW and the differential resistance is 0.09 Ω. In the experiment, the rectangular VCSEL has stable horizontal polarized light and vertical polarized light at working current, and the horizontally polarized light which emerges along the long side of the rectangle always occupy the dominant position. The circular VCSEL in the horizontal and vertical lasing conditions are almost the same. The lasing spectrum of horizontally polarized light appears blue shifted relative to that of vertically polarized light and the blue shift phenomenon is explained by a symmetric three-layer waveguide model. The relationship between the orthogonal polarization ratio of rectangular VCSEL and the aspect ratio of rectangular aperture was studied. The experimental results show that the rectangular column structure can effectively stabilize the polarization direction of the VCSEL and make the large-aperture device lase the high-power polarized laser.