A: Eyepiece consisting of two plano-convex lenses (outer lens dia=9mm , f=15 ; inner lens dia= 20+, f=25) with the flat sides facing inward.
B: objective lens consisting of two plano-convex lenses with the flat sides facing out. Outer lens dia=5, f=8; inner lens dia=5, f=12.
B: objective lens consisting of two plano-convex lenses with the flat sides facing out. Outer lens dia=5, f=8; inner lens dia=5, f=12.
Eyepiece No. 4
Bullseye plano-convex lens for illuminating opaque specimens. Dia=35mm, f=56mm.
The lens is attached to the limb via a spring loaded dovetail (arrow).