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si 2 numerical aperture. In high-speed OCT imaging, in which an tightly fo at only on moves ou scan. Al can be us this meth low-frame focusing physical s We incorporated an axicon lens8 into the sample arm of ti te an al m bu fo in sulting in reduced transverse resolution and a low sig-ibution, m ral ed on he ofan interferometer to achieve both high lateral resolu-on and a greater depth of focus simultaneously. The rm “axicon ” was introduced by McLeod8 to describe optical element that produces a line image lying ong the axis from a point source of light. There are any different kinds of axicon (rings, cylinders, etc.), t the single refracting cone lens is the most common rm. Hence here we refer to an axicon lens as mean-g specifically a refracting conical lens. Using an axi-Fig. 1. Schematic of the sample arm of the OCT syste with an axicon lens to achieve simultaneous high late resolution and greater depth of focus: a, angle form by the conical surface with the f lat surface of the axic lens; b, intersection angle of the geometrical rays with t optical axis; Rz, radius of the incident beam; D, waist the incident beam; L, depth of focus.axial scanning mode (A mode) is used, a cused lens produces a micrometer-sized spot e specif ic depth. The coherence gate quickly t of the shallow depth of focus during the though dynamic focusing compensation3 – 5 ed to overcome this limitation, one can use od only at low speeds and therefore only in-rate OCT systems. In addition, dynamic lenses are bulky and cannot be used when pace is limited, such as in endoscopic OCT.6,7 nal-to-noise ratio in OCT. The intensity distrHigh-resolution optical coher depth range wi