In this project, we designed and simulated a compact bulk-optics wavelength demultiplexer for ASML lithography systems. The device separates a broadband light source (500–1000 nm) into ten distinct spectral bands spaced 50 nm apart, with high transmission (>70%) and polarization insensitivity (<8%). The system must fit within a 150 mm × 150 mm × 40 mm volume and be compatible with multimode fiber input and output. The design is based on reflection and transmission through coated glass plates combined with focusing optics and was modeled and optimized in FRED.
We use the patent: U.S. Patent 8,224,136 as a starting point
For the design we have:
Our result:
We successfully designed and optimized a compact wavelength demultiplexer for ASML lithography systems using sequential coated glass plates without relying on prisms. Both the reflected-based and transmitted-based designs achieved high transmission efficiency (>70%) and polarization insensitivity while maintaining a compact footprint within 150 mm × 150 mm × 40 mm. The reflected-based design reached up to 85% efficiency and 0.05 mm spot radius at the output plane using standard optical components. This work demonstrates a scalable and manufacturable solution for high-performance wavelength separation in advanced optical systems. To further advance these designs, creating custom coatings to fit exact needs of the necessary bandwidths would be ideal and analyzing beam divergence throughout the system would give a better idea of its capability to work with multimode fiber input.