Optical modelling of a supplementary tunable air-spaced goggle lens for rodent eye imaging
Fig 3
Plano air-spaced liquid goggle lens for application in retinal imaging: A/ The plano air-spaced liquid goggle lens consists of two refractive index n1 and n2, split into different optical cavities. At the back of the goggle lens, the first cavity (4–5) introduces a compensatory refractive index mismatch, while on-axis and off-axis residual aberrations are corrected by an auxiliary unit comprising two optical cavities (1–2) and (3–4), with two surface deformations (2) and (3). B/ Each cavity is enclosed between an elastic membrane and a solid partition via a ring holder that allows a push/pull movement of the liquid from the cavity to the reservoir. Thanks to the limited number of elements, the solid partition allows the individual actuation of the surface by fluidic pressure. Different configurations are possible for the front cavity (1–2): (i) for a plano air-spaced goggle lens, the partition is simply a glass plate, (ii) for a convex air-spaced liquid goggle lens, a solid lens is placed at the front of the liquid lens as a replacement of the front glass plate.