AL7560 75 mm Dia. N-BK7 High-Precision; CNC Polished Aspheric Lenses; EFL=60 mm; NA=0.62 Uncoated

The AL7560 is a high-precision asperhic lens offered by Thorlabs, designed for optimal performance in a variety of applications. This lens boasts a 75 mm diameter and is crafted from N-BK7, a high-quality glass commonly used in optical systems due to its excellent transparency and low optical dispersion.

The lens features an effective focal length (EFL) of 60 mm, making it suitable for use in systems where a moderate focal length is required. The asphere is CNC polished, ensuring a high level of precision and surface quality. The lens has a numerical aperture (NA) of 0.62, which is relatively high, allowing for a wide angle of acceptance and increased light-gathering capability.

The lens is uncoated, meaning it does not have any additional layers applied to its surface to alter its optical properties. This can be beneficial in certain applications where the natural properties of the glass are desired, or where cost is a concern. However, it's important to note that uncoated lenses can be more susceptible to surface reflections and may not perform as well in high-light conditions or in systems where multiple optical elements are used.

The lens has a center thickness of 35.5 mm and an edge thickness of 6.8 mm, providing a robust and durable design. The aspheric surface is defined by a series of coefficients, including k1, k2, a2, a4, a6, a8, a10, and a12, which determine the precise shape of the lens.