Biconvex Lenses (Double Convex Lenses)

Biconvex / Double Convex Lenses

Biconvex lenses, also known as double convex lenses, are simple optical lenses with two convex spherical surfaces that bulge out from the center. These surfaces, having the same radius of curvature, focus parallel rays of light to a single point beyond the lens, making them ideal for conjugate imaging systems. Biconvex lenses are frequently employed in positive conjugate setups, where the object and image distances are similar. They are integral components in many imaging devices such as microscopes, cameras, telescopes, and image relays. Additionally, biconvex lenses are used to focus and control laser beams and in telecom IR applications. At Shanghai Optics, we manufacture high-quality biconvex lenses, both coated and uncoated, for a wide range of beam-focusing applications.

The Figure above shows a point light-source located at the focal point of a biconvex lens (for generating a collimated beam.)

Applications of Biconvex Lenses

Although a biconvex lens or double convex lens is a simple lens, it is often included in large multi-lens assemblies. Our biconvex lenses are most suited to applications where the object and virtual images are on different sides of the lens. Ideally, the conjugate ratios (ratio of the image and object distances) should be between 0.2 and 5. Distortions, chromatic aberration, and spherical aberration are minimized when the image and object are equidistant from the lens (1:1 conjugate ratio). When a more distant object must be imaged, plano-convex lenses may be preferred.

Biconvex Lens

Biconvex Lens Specifications

Key specifications of a biconvex lens include the substrate (or optical material), focal length, diameter, and radius of curvature. The optical material used determines the durability of the lens, as well as optical properties like the index of refraction. The focal length of a biconvex lens is simply the distance from the lens to the focal point, measured along the focal axis. This measurement depends on both the optical material and the radius of curvature of the lens itself. The radius of curvature is measured as the distance from the vertex of the lens surface to the center of curvature, measured along the optical axis. The two convex surfaces of a biconvex lens have radii of curvature with equivalent absolute values but different signs.

Biconvex Lenses at Shanghai Optics

At Shanghai Optics, we produce biconvex or double convex lenses using materials such as K9 borosilicate crown glass, BK7 Schott glass, quartz, sapphire, fused silica, CaF2, ZnSe, and germanium substrates. Each of our lenses is carefully polished for optimal surface quality, with edges that are finely ground and beveled. We stock biconvex lenses suitable for UV, visible, and NIR ranges. Our factory-standard, in-stock lenses have a diameter tolerance of ±0.01mm and flatness of λ/10.

Each Shanghai Optics lens is carefully tested for adherence to all applicable standards using state-of-the-art metrology equipment. We check and double-check each piece before it leaves our factory, ensuring that the optics you order are perfectly suited to your application.

Biconvex Lenses Specifications

In addition to our large catalog of in-stock products, we also supply custom lenses upon request. Please contact us to discuss manufacturing limits and custom options, or to receive an up-to-date catalog of on-shelf options.

At Shanghai Optics, we take pride in delivering high-quality biconvex lenses tailored to meet precise specifications. Whether you need stock lenses for UV, visible, or NIR applications, or custom solutions for more specialized requirements, our team is here to support your needs. Each lens is carefully tested to ensure superior performance and reliability in your optical assemblies. Contact us today to learn more about our biconvex lenses and explore how we can enhance your optical designs with precision-engineered solutions. Contact us today for assistance with your custom biconvex lens projects.