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We introduce a new method to make gradient index (GRIN) lenses and GRIN lens arrays by exposing diffusion-driven photopolymers using a low-power CW laser. By changing the size and power of the laser beam and the exposure time the index profile of the GRIN lens can be controlled. Combined with the self-developing nature of the photopolymer, this enables rapid "on-demand" printing of arbitrary micro-optics. We also introduce a new form of scanning phase microscopy that is conveniently integrated into the lens exposure hardware, providing accurate process monitoring.

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We demonstrate single-mode uniform and parabolically tapered three-dimensional waveguides fabricated via direct-write lithography in diffusion-based photopolymers. Modulation of the writing power is shown to compensate Beer-Lambert absorption in the single-photon initiator and to provide precise control of modal tapers. A laminated sample preparation is introduced to enable full 3D characterization of these modal tapers without the need for sample polishing which is difficult for this class of polymer. The accuracy and repeatability of this modal characterization is shown to allow precise measurement of propagation loss from single samples. These testing procedures are used to demonstrate single-mode waveguides with 0.147 dB/cm excess propagation loss and symmetrical tapers up to 1:2.5 using 1.5 microwatts of continuous write power.

6,13-Dichlorotriaryldioxazines (DClTADO) 1 have been synthesized from 2,5-bis(arylamino)-3,6-dichloro-1,4benzoquinones (BADClBQ) 2 by oxidation with (diacetoxyiodo)benzene (DIB) under mild conditions in good yields.