Round Biconcave Lens, 50 mm Diameter, Various Focal Lengths

Description

The Round Biconcave Lens, 50 mm Diameter, Various Focal Lengths, also known as a double-concave lens, diverging lens or negative focal length lens, is designed for investigating light refraction, image formation and geometrical optics in educational and laboratory environments. The biconcave optical design features two inward-curved surfaces, making the lens thinner at its centre than at its edges. This shape causes parallel incident light rays to spread apart after passing through the lens, demonstrating the fundamental behaviour of diverging lenses. Each lens has a standard diameter of 50 mm, providing a consistent circular format for use with suitable optical benches, lens holders and educational physics apparatus.

The range includes eight nominal focal lengths: 5 cm, 10 cm, 15 cm, 20 cm, 25 cm, 30 cm, 50 cm and 100 cm. These variations allow students to compare the effects of different lens curvatures and focal lengths on transmitted light. Biconcave lenses have a negative focal length under the conventional Cartesian sign convention. The listed focal lengths represent their magnitudes, so a 10 cm biconcave lens has a nominal signed focal length of −10 cm. The shorter focal length variations produce stronger divergence of parallel incident light rays, while longer focal lengths produce weaker divergence under comparable conditions. This makes the range useful for demonstrating relationships between focal length and optical power.

These lenses are supplied in an unmounted configuration, allowing them to be positioned in compatible laboratory lens holders. Their design supports practical experiments involving optical alignment, light ray tracing and the formation of virtual images. During a typical optics experiment, students can direct suitable light rays through the lens and observe their divergence. By extending the refracted rays backwards, they can identify the virtual focal point and investigate the behaviour of negative lenses. A biconcave lens can also be used with a biconvex lens in educational optical arrangements to demonstrate how combinations of converging and diverging lenses affect image formation and the effective focal length of an optical system.

These optical lenses are suitable for physics education, laboratory light experiments and introductory optical investigations, helping students understand lens properties through practical observation. Safety Precautions: Handle optical lenses carefully to avoid scratches, chips and breakage. Clean the surfaces using suitable optical cleaning materials. Avoid direct exposure to intense light beams and follow appropriate safety procedures when using laboratory light sources. Each selected variation is supplied as one Round Biconcave Lens, 50 mm Diameter, in the chosen focal length. Lens holders, optical benches, light sources and other accessories are not included unless specified separately.

LabChoice Australia supplies laboratory lenses, optical components and educational physics equipment for secondary schools, universities, research institutions and science teaching facilities across Australia.