Direct laser writing (DLW) has been shown to render 3D polymeric optical components, including lenses, beam expanders, and mirrors, with submicrometer precision. However, these printed structures are limited to the refractive index and dispersive properties of the photopolymer. Here, we present the subsurface controllable refractive index via beam exposure (SCRIBE) method, a lithographic approach that enables the tuning of the refractive index over a range of greater than 0.3 by performing DLW inside photoresist-filled nanoporous silicon and silica scaffolds. Adjusting the laser exposure during printing enables 3D submicron control of the polymer infilling and thus the refractive index and chromatic dispersion. Combining SCRIBE’s unprecedented index range and 3D writing accuracy has realized the world’s smallest (15 µm diameter) spherical Luneburg lens operating at visible wavelengths. SCRIBE’s ability to tune the chromatic dispersion alongside the refractive index was leveraged to render achromatic doublets in a single printing step, eliminating the need for multiple photoresins and writing sequences. SCRIBE also has the potential to form multicomponent optics by cascading optical elements within a scaffold. As a demonstration, stacked focusing structures that generate photonic nanojets were fabricated inside porous silicon. Finally, an all-pass ring resonator was coupled to a subsurface 3D waveguide. The measured quality factor of 4600 at 1550 nm suggests the possibility of compact photonic systems with optical interconnects that traverse multiple planes. SCRIBE is uniquely suited for constructing such photonic integrated circuits due to its ability to integrate multiple optical components, including lenses and waveguides, without additional printed supports.

直接激光写入（DLW）已被证明可以渲染亚微米级精度的3D聚合物光学组件，包括透镜，扩束器和反射镜。然而，这些印刷结构限于光敏聚合物的折射率和分散性能。在这里，我们介绍了通过束曝光（SCRIBE）方法进行的表面下可控制的折射率，该方法是通过在填充有光致抗蚀剂的纳米多孔硅和二氧化硅支架内进行DLW来实现大于0.3范围内的折射率调节的光刻方法。在打印过程中调整激光曝光量可实现聚合物填充物的3D亚微米控制，从而实现折射率和色散的控制。结合SCRIBE前所未有的索引范围和3D写入精度，已经实现了世界上最小（直径15 µm）的球形Luneburg透镜，该透镜在可见光波长下工作。利用SCRIBE调整色散和折射率的能力，可以在单个印刷步骤中实现消色差双胶合透镜，从而无需使用多个光敏树脂和写入序列。通过将光学元件级联在支架中，SCRIBE还具有形成多组件光学元件的潜力。作为演示，在多孔硅内部制造了产生光子纳米射流的堆叠聚焦结构。最后，将全通环形谐振器耦合到地下3D波导。在1550 nm处测得的质量因数为4600，这暗示了紧凑的光子系统具有穿越多个平面的光学互连的可能性。SCRIBE具有集成多种光学组件（包括透镜和波导）的能力，而无需额外的印刷支撑，因此特别适合构建此类光子集成电路。