Fig. 3.

(a) Front view of hand-held OCT probe with housing. (b) Simplified section view showing internal optical and mechanical configurations. Internal connections including optical fiber and electrical wires are omitted. Outer housing and mechanical positioning components are simplified. SCRo - Screen for operator, SCR_f - Screen for subject eye fixation. Gx/Gy - Galvanometers, f_s - Scanning lens, DCM₁- Dichroic mirror to separate OCT beam, DCM₂ - Dichroic mirror to separate iris viewer light, M_s - Reflection mirror for fixation screen. f_sr – Fixation screen relay lens, f_cr – iris viewer CCD relay lens, f_oph – Ophthalmic lens. (c) Typical iris viewer image during data acquisition (d) Examples of fixation screen display contents, upper image is a target for adult retina imaging, bottom image is for pediatric imaging.