HARTLEY’S ROTATABLE OPTICAL DISC

1. It is very useful for exploring the various concepts of optics involving reflection and refraction using the ray tracing technique.
2. It consists of a white painted steel disc, which is approximately 250 mm in diameter.
3. It is marked from 0 to 360° at every 1 degree, with centre mark.
4. It is mounted on a stable cast iron base.
5. The main disc and the lamp house can be rotated and held in any desired position.
6. With the lamp house, a rotatable disc with single, double, triple and quadruple slits and with an adjustable lens carrier with lens for divergent, parallel or convergent light beams is provided.
7. The disc is supplied with a set of reflective and refractive optical elements.

Optical elements provided for reflection include one each of  a 50 × 25 mm:

• Plane glass mirror and
• Polished plated metal cylindrical mirror.

Optical elements provided for refraction include one each of a :

• Semicircular Acrylic block
• Biconvex Lens
• Biconcave Lens
• Right angled prism and
• Trapezoidal acrylic block.

These optical elements have powerful magnets attached for placing them securely on the disc.

The bottoms of all the components are frosted to minimize internal reflection.