optical axis

They also discovered that the optical vortices could be modified by adjusting the topological charge, which is essentially the number of windings around the optical axis.

The authors selected a particular value for θ1 and the orientations of the polarizers, and varied the solid crystal’s optical axis — a direction in the crystal along which the speed of propagating light is independent of the light’s polarization.

The Casimir torque, although weak, forced the average orientation of molecules in the nematic liquid crystal along a direction that11 characterizes the solid crystal, known as its optical axis.

The tilting screen design in particular stands out as unique, with a twisting mechanism that allows the 3.2-inch panel to be viewed at various angles while remaining on the lens' optical axis, and the screen also has a light on the rear so the camera's buttons can be seen in dark conditions.

Shifting one of those lenses slightly along the optical axis changes the diameter of the ring, making it suitable for biological organisms across a broad range of sizes: not just sperm, but algae, microbes, etc., as well.