The application of a commercially available spatial light modulator (SLM) to control the spatial intensity distribution of a nanosecond pulsed laser for micromachining is described for the first time. Heat sinking is introduced to increase the average power handling capabilities of the SLM beyond recommended limits by the manufacturer. Complex intensity patterns are generated, using the Inverse Fourier Transform Algorithm, and example laser machining is demonstrated. The SLM enables both complex beam shaping and also beam steering.

(accessed July 10, 2009).The capabilities of a high average power picosecond laser are assessed for micromachining yttria‐stabilized tetragonal zirconia polycrystal (Y‐TZP) in its hard state. Laser machining of this material presents an attractive alternative to conventional machining techniques when precision customized parts are required due to the difficulty in machining Y‐TZP in its hard state. Compared with previous nanosecond work the picosecond laser enables similar micromachining to be carried out at the same rate but with a superior surface finish and with no evidence of surface cracking. Strength measurements have been carried out using a four‐point bend test rig and confirm that the improvement in surface quality translates to higher strength in machined components.

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a b s t r a c tWe report the development of a laser-based process for the direct writing ('microsculpting') of unique security markings (reflective phase holograms) on the surface of metals. In contrast to the common approaches used for unique marking of the metal products and components, e.g., polymer holographic stickers which are attached to metals as an adhesive tape, our process enables the generation of the security markings directly onto the metal surface and thus overcomes the problems with tampering and biocompatibility which are typical drawbacks of holographic stickers. The process uses 35 ns laser pulses of wavelength 355 nm to generate optically-smooth deformations on the metal surface using a localised laser melting process. Security markings (holographic structures) on 304-grade stainless steel surface are fabricated, and their resulted optical performance is tested using a He-Ne laser beam of 632.8 nm wavelength.

Large scale scene generation is a computationally intensive operation, and added complexities arise when dynamic content generation is required. We propose a system capable of generating virtual content from non-expert input. The proposed system uses a 3-dimensional variational autoencoder to interactively generate new virtual objects by interpolating between extant objects in a learned low-dimensional space, as well as by randomly sampling in that space. We present an interface that allows a user to intuitively explore the latent manifold, taking advantage of the network’s ability to perform algebra in the latent space to help infer context and generalize to previously unseen inputs.