The present invention is directed to an achromatic endoscope which employs a diffractive microlens. Along with a broadband rotary joint and a custom 800 nm SD-OCT system, ultrahigh-resolution 3D volumetric imaging over a large area becomes possible. The diffractive microlens can be used directly with a GRIN lens, making the endoscope design simpler and cost effective. Preliminary ex vivo 3D intraluminal imaging was performed with the endoscope in conjunction with a home-built broadband rotary joint and a spectral-domain OCT system, demonstrating the performance of the diffractive endoscope. Considering the miniature OCT imaging probe is the required component for using the OCT technology in internal organs, the proposed approach will have a broad impact on endoscopic OCT imaging by improving OCT resolution in any applications that involve a miniature OCT probe, as intravascular OCT imaging, gastrointestinal (GI) tract imaging, airway imaging etc.
