Physics > Light & Optics > Lenses, Mirrors, Prisms & Slabs

Focal Length (cm)

Dia mm (1) (2) (3) (4) (5) (6) (7) (8)

A 38 5 10 15 20 25 30 50 100

B 50 5 10 15 20 25 30 50 100

C 75 5 10 15 20 25 30 50 100

D 100 5 10 15 20 25 30 50 100

Made from optically worked glass, ground edges.

Focal Length (cm)

Dia mm (1) (2) (3) (4) (5) (6) (7) (8)

A 38 5 10 15 20 25 30 50 100

B 50 5 10 15 20 25 30 50 100

C 75 5 10 15 20 25 30 50 100

Made from optically, worked glass, round edges and polished faces, dia 50 mm. one each double convex, plano-convex, concave-convex, convexo-concave, double concave, plano-concave, in wooden case.

Wooden, for lenses or mirrors upto 75 mm dia, 100 mm high upright with V-slot mounted on base. An index mark is engraved at each end of the base.

With sides grooved to take lenses or mirror, black painted

(a) For 38 mm dia (b) For 50 mm dia

Glass, unmounted, back silvered with protective coating

(a) 50 x 50 mm (b) 75 x 25 mm (c) 75 x 75 mm (d) 100 x 75 mm (e) 150 x 25 mm (f) 150 x 50 mm (g) 150 x 100 mm

Wooden with slot on one side to take mirrors.

(a) 50 x 50 x 50mm (b) 75 x 50 x 50mm (c) 100 x 50 x 50mm

Glass, optically worked, back silvered both concave & convex type. I : Convex (cx) II : Concave (cv)

(I) CV (II) CX

Dia (mm) Focal Length(mm)

a) 38 75

b) 38 100

c) 38 150

d) 38 200

e) 38 300

f) 50 75

g) 50 100

60° x 60° x 60° , polished faces.

Side (mm) Height (mm)

a) 25 25

d) 38 38

e) 50 50

f) 62 62

90° x 45° x 45° polished faces.

Hypotenuse (mm) Height (mm)

a) 35 25

b) 54 38

c) 70 50