The paper presents a broadband achromatic metalens designed to focus and image in the visible spectrum. The authors demonstrate that by carefully designing nanofins on a surface, it is possible to control the phase, group delay, and group delay dispersion of light, achieving a transmissive achromatic metalens with a large bandwidth. The metalens can achieve diffraction-limited focusing and imaging from 470 to 670 nm, with a numerical aperture (NA) of 0.2. The design is based on the principle of engineering the frequency-dependent phase profile to achieve arbitrary control of dispersion over a wide continuous bandwidth. The metalens is composed of a single layer of nanostructures, each with a thickness on the order of the wavelength, and does not involve spatial multiplexing or cascading. The authors discuss potential optimizations to improve efficiency and applications in various fields such as cameras, lighting, displays, and wearable optics.The paper presents a broadband achromatic metalens designed to focus and image in the visible spectrum. The authors demonstrate that by carefully designing nanofins on a surface, it is possible to control the phase, group delay, and group delay dispersion of light, achieving a transmissive achromatic metalens with a large bandwidth. The metalens can achieve diffraction-limited focusing and imaging from 470 to 670 nm, with a numerical aperture (NA) of 0.2. The design is based on the principle of engineering the frequency-dependent phase profile to achieve arbitrary control of dispersion over a wide continuous bandwidth. The metalens is composed of a single layer of nanostructures, each with a thickness on the order of the wavelength, and does not involve spatial multiplexing or cascading. The authors discuss potential optimizations to improve efficiency and applications in various fields such as cameras, lighting, displays, and wearable optics.