47-727 15 mm Dia. L-BAL35 Precision Aspheric Lens; EFL=18.75mm; NA=0.4 Uncoated

The 47-727 is a high-precision aspheric lens offered by Edmund Optics. This lens, with a catalog number 47-727, is made from L-BAL35 material, a product of Ohara. The lens is uncoated, which means it does not have any additional layers to enhance its optical properties.

The lens has a base shape of a circle and a diameter of 15 mm. The edge thickness of the lens is 1.82 mm, and it has an effective focal length (EFL) of 18.75 mm. The lens's numerical aperture (NA) is 0.4, indicating a wide acceptance angle and high light-gathering capability.

The lens's geometry is defined by several parameters. The inner radius is 0, and the outer radius is also 0, suggesting a symmetrical design. The lens's front and back surfaces have different radii of curvature, with r1 being 11.046 mm and r2 being 0. The back focal length (BFL) is 15.92 mm, and the center thickness is 4.5 mm.

The lens's aspheric surface is defined by a conic constant (k1) of -1.832442. This value indicates a relatively steep aspheric surface, which can help reduce spherical aberration and improve image quality. The lens's front surface has a small amount of spherical aberration (e front = 0.000116685), but this is typical for lenses of this type.

The lens is designed for use at a single wavelength of 587.6 nm. This wavelength is in the middle of the visible spectrum, making the lens suitable for applications in visible light.