357775-405 6.325 mm Dia. D-LAK6 Molded Glass Geltech Aspheric Lenses; EFL=4 mm; NA=0.6 405nm V-Coat

The 357775-405 is a high-quality aspheric lens, designed and manufactured by Thorlabs. This lens is molded from D-LAK6 glass, a material known for its excellent optical properties. The lens has a diameter of 6.325 mm and a thickness of 1.59 mm at the edge, making it suitable for a wide range of optical applications.

The lens features an effective focal length (EFL) of 4 mm, which is a crucial parameter in lens selection. The EFL determines the lens's magnification power and is a key factor in determining the overall optical system's performance. The lens also has a numerical aperture (NA) of 0.6, which is a measure of the lens's light-gathering ability. A higher NA allows for a wider field of view and greater resolution.

The 357775-405 lens is coated with Thorlabs' proprietary V-Coat, which is designed to reduce reflection and increase transmission at the 405 nm wavelength. This coating ensures optimal performance in applications that use this specific wavelength, such as fluorescence microscopy or DNA sequencing.

The lens's aspheric design is another notable feature. Aspheric lenses have a more complex surface profile than traditional spherical lenses, which allows them to correct for spherical aberration and provide superior image quality. This makes the 357775-405 an excellent choice for applications that require high resolution and sharp imaging.