School of Physics, University of KwaZulu-Natal, Private Bag X54001, Durban 4000, South Africa.
Nat Commun. 2013;4:2289. doi: 10.1038/ncomms3289.
Customizing the output beam shape from a laser invariably involves specialized optical elements in the form of apertures, diffractive optics and free-form mirrors. Such optics require considerable design and fabrication effort and suffer from the further disadvantage of being immutably connected to the selection of a particular spatial mode. Here we overcome these limitations with the first digital laser comprising an electrically addressed reflective phase-only spatial light modulator as an intra-cavity digitally addressed holographic mirror. The phase and amplitude of the holographic mirror may be controlled simply by writing a computer-generated hologram in the form of a grey-scale image to the device, for on-demand laser modes. We show that we can digitally control the laser modes with ease, and demonstrate real-time switching between spatial modes in an otherwise standard solid-state laser resonator. Our work opens new possibilities for the customizing of laser modes at source.
从激光中定制输出光束形状通常需要专门的光学元件，如孔径、衍射光学元件和自由曲面反射镜。这些光学元件需要大量的设计和制造工作，并且还存在另一个缺点，即与特定空间模式的选择不可变地连接。在这里，我们通过第一个数字激光解决了这些限制，该数字激光包含一个电寻址反射型纯相位空间光调制器作为腔内数字寻址全息镜。通过向设备写入计算机生成的灰度图像形式的全息图，可以简单地控制全息镜的相位和振幅，以实现按需激光模式。我们证明可以轻松地对激光模式进行数字控制，并在标准固态激光谐振器中演示了空间模式的实时切换。我们的工作为激光模式的定制提供了新的可能性。
