skip to content

Centre for Photonic Devices and Sensors


Transparent Conductors(TC) for Middle Infrared(Mid-IR) liquid crystal spatial light modulators(LC-SLM)


In the Mid-IR(λ = 2 to 5 μm) range, LC-SLMs can offer a low-cost, non-mechanical and compact alternative to the gimbaled mirrors used currently for Mid-IR laser beam-steering. Unfortunately typical indium tin oxide (ITO) TC layers have a transmittance < 20% for Mid-IR wavelengths. Ni UTMFs and CVD monolayer graphene are proposed as an alternative. Transmissive BL-037 LC cells with a maximum phase shift of 3π at λ=2.3 μm were assembled with both materials as TCs on sapphire, with the graphene performing considerably better: Transmittance of 81.1% and contrast ratio of 50.7. LCOS implementation and novel device architectures will be investigated.