Liquid crystal lasers for ophthalmics

Lasing in cholesteric liquid crystal systems was achieved experimentally in 1980 [1] however, as of yet, there have been no successful applications for these lasers. Here we discuss the potential integration of liquid crystal lasers (LCLs) into ophthalmic applications.
Ophthalmic imaging currently utilises systems that probe the condition of the retina by visualising fluorescence or by injecting fluorescent dyes to generate angiograms. Autofluorescence is commonly used to detect biomarkers within the retinal pigment epithelium such as A2E, a fluorophore thought to be indicative of degenerative retinal diseases. [2] The assessment of ocular health requires lasers ranging the visible spectrum from lipofuscins (450 nm) to melanin (800 nm) [3]. Current tuneable laser systems are extremely expensive, bulky and require extensive cooling systems and single laser portable devices would lack specificity. The necessity for a portable, continuously tuneable device is evident in this field.
The tuneable, self-assembling structure of LCs combined with organic dyes allows us to make lasers spanning the entire visible spectrum (450 – 800 nm) [4]. The cost, size and relative ease of production of these cells makes them attractive for potential utilisation in fluorescence imaging in this context. The ability to switch between specific wavelengths designed to image clinically relevant biomarkers could shorten diagnosis time and reduce the need for large numbers of bulky equipment.