189 entries in this trade.
A phenomenon where light, instead of passing into a medium of a lower refractive index and refracting away from the normal, is completely reflected by the boundary between the two media because it approaches at an angle greater than or equal to the critical angle.
Of or pertaining to corrective lenses that have three different powers per eye.
Spectacles with corrective lenses that have three different powers per eye.
A measure of convergence or divergence of rays.
The point where the surface of a lens crosses the optical axis.
Chiefly in virtual focus: of a focus or point: from which light or other radiation apparently emanates; also, of an image: produced by light that appears to diverge from a point beyond the reflecting or refracting surface.
A point from which light or other radiation apparently emanates, such as in the virtual image produced by a plane mirror.
The image formed by light rays diverging from a convex mirror or concave lens
A magneto-optical phenomenon which rotates and elliptizes linearly polarised light sent into an optically active medium.