Direct laser writing with a slit-beam dynamically controlled with a phase spatial light modulator

We present the use of a spatial light modulator operating as a phase modulator to create a dynamic slit at the pupil plane of the objective. The dynamic updating of the slit size, shape, position and angle allows for the aspect ratio improving slit method to be applied to more complex structures beyond straight waveguides and channels and to higher numerical aperture objectives that possess lateral asymmetry due to depolarization effects.